Do-it-yourself computer mouse. We repair a computer mouse with our own hands: everything is not as difficult as it seems

REPAIR OF A COMPUTER MOUSE

Those who actively use computers (namely desktop PCs or laptops, not tablets or smartphones) have probably seen from their own experience that computer mice are the least reliable devices in computer technology. I am sure that many PC users at home have accumulated a decent arsenal of these unpretentious devices, which over time have a habit of stopping functioning normally, or completely failing. I myself have accumulated a little less than a dozen of these "creatures" at home. It would seem, what's the trouble? Just think, this inexpensive device failed. After all, the cost of a computer mouse usually ranges from 2 to 7 US dollars (depending on the manufacturer and functionality, these devices, of course, can cost much more). But, firstly, when it comes to a dozen pieces, then this is not such a small amount. And, secondly, the most unpleasant thing is that this "beast" usually fails at the most inopportune moment, when there is nothing to replace it with, and in order to buy a new one, you need to run almost through half the city.

After another UNTIMELY mouse failure, when a spare was not at hand, and all the nearest computer stores were closed, I thought: “what the hell, because these mice are not so complicated and are probably easy to repair.” So I decided to try to restore 1-2 pieces. After 45 minutes of not very difficult work, the entire arsenal of my "pets" (computer mice) was restored and functioned properly. Now that I have some time, I decided to write a short article describing the process of repairing computer mice.

Computer mouse device

To begin with, let's take a look at the device of computer mice and their purpose. The computer mouse is one of the main devices for using the GUI of operating systems on desktops and laptops. There are many variants of computer mice.

Functionally, they consist of:

1. Movement sensor (optical, mechanical, induction, gyroscopic, etc.).
2. Two or more buttons to send various commands to the computer.
3. A control element for "scrolling" web pages, text and graphic documents (joysticks, control wheels, touch devices, etc.).
4. Means of connecting to a computer (wireless with a transmitter and receiver of information, wired with a connector for connecting to a PC).

Structurally, computer mice consist of a case with drives for buttons, an electronic circuit (can be made in the form of one or more microcircuits), a system of sensors, buttons and wires. Wireless mice have means of transmitting and receiving information. Wired mice, depending on the type of connector used, can be with a USB or PS / 2 interface.

Note: We will consider one of the cheapest and most common options - a wired optical mouse with two buttons, a control wheel and a USB interface.

Common malfunctions of computer mice

The list of common faults includes:

1. Loss of cursor control or unstable control.
2. Stopping the computer from responding to button presses.
3. Lack of response to the rotation of the control wheel, or erratic response (the effect of "slipping" of the rotation of the wheel).

Standard causes of malfunction of computer mice and external manifestation

Usually problems with the operation of computer mice arise for the following reasons:

1. The lack of a driver on your PC for a particular computer mouse. Outwardly, it manifests itself in the complete (or partial) lack of cursor control on the computer screen from the connected mouse. When you connect the mouse to the computer, the information "Device not recognized" is displayed.
2. Lack of response to pressing one or more buttons due to a broken micro-button or a broken wire.
3. Intermittent cursor control or no control at all. This is usually due to a break in one or more of the wires connecting the mouse to the computer connector.
4. “Slippage” of the scrolling of web pages, text and graphic documents when the control wheel is rotated. This is usually due to the mechanical wear of the steering wheel axle tip connected to the rotation sensor. With mechanical destruction of the axle tip, there is a complete lack of reaction of the cursor to the rotation of the control wheel.
5. Failure of one or more functional nodes of the mouse.

Depending on the specific design and functionality of the computer mouse, there may be other manifestations of malfunctions. But, because in this case, we will consider an ordinary optical mouse of “Chinese nationality”, as the most common in use due to its cheapness, we will not mention them.

Computer mouse repair algorithm

Repair of a computer mouse can conditionally be divided into the following stages:

1. Check and install (if necessary) the appropriate driver.
2. Disassembly of a computer mouse.
3. Direct troubleshooting.
4. Assembly of a computer mouse.
5. Checking the performance of a computer mouse.

Checking and installing the computer mouse driver

Usually, computer mice are made using Plug and Play technology (plug and play) and do not require additional software. Some (more sophisticated) computer mice may come with installation drivers, but even if you don't have them, you can always download them from the mouse manufacturer's website. In addition, Windows 7 operating systems and higher have a fairly powerful built-in search system for computer device drivers.

You can set the automatic search for drivers (for any device, not just for computer mice) from the device manager. To launch the Device Manager, launch the Control Panel program built into the Windows operating system and open the Device Manager. The path to it is Control Panel\System and Security\System\Device Manager. In addition, the "Device Manager" can be called up using the "Search" function built into Windows. For Windows 7, click the Start button, and in the Search box, type Device Manager (in Windows 10, click the Search Windows button, which is located to the right of the Start button). In the search results, you will have a link to the Device Manager executable file, by clicking on which you will open the Device Manager window (see Fig. 1). In this window, find the item "Mice and other pointing devices" (see 1 Fig. 1), expand it, and double-click the left mouse button on the button "HID - compatible mouse" (see 2 Fig. 1).

After that, you will see the "Properties: HID - compatible mouse" window (see 3 Fig. 1), which you need to open on the "Driver" tab, see 4 Fig. 1. Then you need to click on the "update driver" button, see 5 Fig. 1, after which the window Fig. 2 will open in front of you.

In the new window Fig.2, select the item "Automatic search for updated drivers" (see 1 Fig.2). After that, your PC (if it is connected to the Internet) will go into search mode and find you the latest working driver, or indicate that the existing driver does not require updating.

Disassembly of a computer mouse

Most optical mice with USB interface, see Fig.3, consist of two parts: the top - cover (see 1 Fig.3 and 1 Fig.4), and the bottom - base (see 2 Fig.3 and 2 Fig.4) , which are attached to each other with the help of 1 self-tapping screw (see 3 Fig. 4) and two plastic easily removable locks (see 4 Fig. 4).

Unscrew the self-tapping screw (see 3 Fig. 4) from the socket (see 3 Fig. 3), lift the rear part of the mouse body cover and, slightly pushing the cover back, disengage the plastic locks. Remove the cover. The disassembled mouse is shown in Fig.4. The appearance of the contents of your mouse will certainly be different from that shown in Fig. 4, but do not be confused by this. The principle of repair of most optical computer mice is similar to that described below.

Computer mouse repair

After you have disassembled the mouse, you can proceed directly to troubleshooting.

As for the elimination of wire breaks, they are eliminated by soldering. Usually, breaks occur in the area where they are connected to the board (see 4 Fig. 4), but they can also be in the area where the cable enters the mouse body (see 5 Fig. 4), and even in the area of ​​the USB connector. In the latter case, use the tips presented in the article "", but at the same time I will immediately make a reservation that your mouse recovery time will increase significantly.

The problem with the "slip" of the control wheel (see 6 Fig.4 and 1 Fig.5) occurs due to the wear of the tip of the steering wheel axle (usually, it has a hexagonal shape (see 2 Fig.5)). This "trouble" is easily eliminated if, in parallel with the tip, several strands (see 4 Fig. 5) of a stranded copper wire (see 5 Fig. 5), which have about 0.05 mm in diameter. It is necessary to insert copper wires with the steering wheel removed, and only then install the wheel axle in place. This should be done without much effort so as not to damage the steering wheel rotation sensor and the hexagonal tip of the axle (see 2 Fig. 5). After you seal the connection between the tip of the steering wheel axle and the sensor, cut off the protruding wires with side cutters or ordinary nail scissors.

Sometimes the cause of a malfunction of computer mice may be the failure of a functional unit. In this case, the repair becomes more complicated and consists in replacing faulty components. As a repair kit for such a repair, you can use serviceable nodes from other faulty mice, if you did not save money when buying these products, but took several at once.

You should be aware that all functional devices of computer mice are easily dismantled and put in place, up to microcircuits with round leads. But to dismantle faulty microcircuits, it is advisable to use medical needles with an inner diameter slightly larger than the diameter of the microcircuit output. Insert 1 pin of the microcircuit into the hole of the medical needle and use a soldering iron with a thin tip to heat the needle at the point of contact of the microcircuit with the printed circuit board. After the solder has melted, and the needle passes through the hole in the printed circuit board with little effort, remove the soldering iron and, turning the needle, let the soldering place cool. Do the same with the rest of the contacts of the microcircuit. Remove the faulty chip, and then replace the faulty chip with a good one and solder it.

The last of the proposed repair methods is rather laborious, and it is advisable to do it only in the case of repair of expensive products.

Assembling a computer mouse

The computer mouse is assembled in the reverse order of its disassembly. First install on the base of the mouse (see 2 Fig. 4) all its functional elements, laying the cable in such a way that it does not interfere with the installation of the cover (see 1 Fig. 4). Then, easily removable locks are connected with the back of the mouse cover slightly raised and a self-tapping screw is screwed in with the cover pressed against the base of the mouse body.

1. In order to be able to replace faulty components when repairing computer mice, it is advisable to buy several mice of the same type at once.
2. If the mouse is out of order, or the quality of its work does not satisfy you, do not rush to throw it away. Perhaps the above recommendations will help you restore it.
3. Usually, most of the malfunctions that appear during the operation of computer mice made in China are laid down at the stage of their manufacture. Therefore, after repair, these mice serve for quite a long time. In this regard, often the repair of these simple products is technically and economically justified.

Itsenko Alexander Ivanovich

Have you ever wondered how things work, how they go from idea to implementation, how simple simple things are? How easy is it to make a comb? What about a computer mouse? What about a wooden computer mouse made of solid mahogany with an LCD screen, with its own electronics and a cable made and braided especially for it? I think you will be interested in my path, which I went through in 2.5 years of creating my mouse.

Design, construction, modeling

Since I was a complete zero in design, I approached the matter as a complete layman. I bought plasticine and began to sculpt the mouse of my dreams. First, I made a mouse, which is perfect for my desktop work. She is a large dark gray in the photo. Then I molded a mouse that would suit me as a mobile one (dark gray small). And then I took the piece of plasticine stolen from the children to work, and my colleagues fashioned a mouse that claims to be called “folk”. It ideally fit into the hand of the majority of the male population of our team (multi-colored in the photo). And what? The result is banal and dull forms that we twitch day and night with our hands in every way. Apparently, among the three standard mice, any user will find a comfortable one. Celebration of the ideal?
As a result, a mouse was simulated behind the computer, which, from my point of view, claimed to be elegant and beautiful.
At that time I really liked her. And without thinking twice, I divided the computer model into parts. The elements of fastening and interfacing with electronic filling were thought out. It sounds simple, but in fact, hundreds of hours of painstaking work were spent.
After that, the resulting parts were grown on a 3D machine to check the assembly.
Material - polyamide. In the hand sits well, like a glove. All parts fit together, the technological assembly also went without problems
The next step is milling in wood. I bought, probably, a dozen different species of redwoods, but I started with a sapele tree, the rest of the species are waiting in the wings.

Didn't like the design. The vertical gaps between the buttons and the case looked bad and untidy. Technological “sores” are visible when working with wood - chips and removal of the tree. Well, and most importantly - the keys did not bend, there was no click.
I thought about the design for a long time. Something was embarrassing, and there was no feeling of satisfaction. Then I realized - the mouse lacks solidity. I decided to return to the original version of the mouse, which I sculpted at the very beginning, only at a professional level and using sculptural clay. In one mouse, two design options are made. Convenient for comparison and decision making.
After receiving the final version, 3D scanning was done and the surfaces were transferred to SolidWorks.
The second model was not much better than the first. The buttons were not pressed, and it was impossible to fix this in the current model. The marriage of the model was laid down at the DNA level. We need a more integrated approach with simultaneous control of both design and technology. Otherwise, nothing will work. There will be either technological excellence or good design, but not all at once. These characteristics sit on different sides of the swing. So I throw everything in the trash and start from the beginning. Sketch-design-sculpting-testing-growing and so on, but with technological control of critical parameters on the one hand, and design on the other. We are looking for the golden mean.
The third model was already made as part of the classic product design cycle. Started with a sketch.
Outlines have been drawn.
And finally, the approved design.
Plasticine layout.
3D scanner getting the surface.
computer model.
Then the process of fine-tuning the hull began. On the CNC machine, the body was sawn out, tested, refined, then sawn out again. As a result, only the tenth version of the case turned out to be operational. The biggest problem was to make keystrokes comfortable. As a result, in some places the thickness of the tree decreased to 0.7 mm! It took me a year to finish the hull.
The wheel and connector were also made of wood.
I laser engraved the Clickwood brand on the wheel.
The eleventh version of the corps is on the way, where I will make minor changes. I also started developing a wireless version of the mouse. The wireless module is based on Bluetooth technology, the optosensor is laser. AAA batteries, 2 pieces, replaceable. When recharging, the mouse will continue to work. All the elements are located very tightly, while arranging I had to pretty rack my brains. A cavity specially cut into the wooden case of the mouse serves as a container for the batteries.

wooden details

Working with wood begins with the selection of wood. The boards must be of the correct geometry, have a minimum of knots and defects, and have the necessary moisture content. At first, the boards are dried at home. At least six months.
After that, the board is sawn into small bars, which are dried for several weeks at the place of their further processing. At all stages, the humidity is controlled by a special device. If the drying process is neglected, the wood loses its geometric stability, and the manufacture and operation of the mouse becomes impossible. Prepared bars are processed on a CNC machine using a specially created program.
From the very beginning of the creation of the part and until the final assembly of the mouse, the parts are rigidly fixed on a metal fixture so that the part does not change its shape and geometric dimensions at any of the stages.

The processing of the upper part of the mouse has to be done with a jeweler's precision, since its profile is designed for a soft click and is very thin in some places. I control the pressing force with a grammeter. In normal mice, it ranges from 50 to 75 gauss. I'm trying to get 50 GS.
The tree in my project is the biggest challenge. Not only is this the most significant part of the cost, but the share of marriage here is very high. Wood is an anisotropic material. It can lead, defects can occur, chips can occur, and just a mistake in the finishing coating technology can lead to the fact that the mouse body is sent to the trash. I confess that I am still improving the processing technology, and I am not completely sure that I found the right one. For statistics: in the first batch of ten cases, only three reached the finished product. Therefore, the part of the technological chain associated with wood is critical for the cost and quality of the finished product. Above it is a constant work. In the future, I plan to work with bone. In particular, I am already engaged in the creation of a bone wheel.

Electronic part

I developed the first mouse circuit on my own. As a sensor, I took the top-end optical sensor ADNS-3090 from Avago, the controller from Atmel, the rest of the components from branded companies such as Murata, Yageo, Geyer, Omron and Molex became the brains.
He paid special attention to the quality nutrition of the mouse, here, in my opinion, he reached the absolute with his perfectionism
First working layout.
In black, final.
There were also experiments with various buttons. I've always tried to find a quiet mouse among others. Well, since I do it myself, I decided to conduct an experiment and make such a mouse and test it in work. To do this, I replaced the clicking left and right “mics” with soft and quiet ones used for the central button (did you notice that the central button always clicks quieter?). A special version of the board was created, where all three identical "mics" were mounted.
The mouse was in operation for a couple of weeks, and I can share the conclusion: in my case, the lack of a click is uncomfortable. The wood partly absorbs the click, and the wood keys feel tight and you have to press harder. It is difficult to describe the feeling, but the closest analogy is as if under the finger there is a mouse key made of soft, bread crumb, wood, and for a sure click you need to squeeze it. The experiment can be considered successful, since a clear result was obtained, what should be the response from pressing the mouse button - clear, sonorous, unambiguously interpreted. Picked up and bought a batch of gold-plated connectors for the mouse. As usual, in China. I don’t know about “better contact”, but they harmonize perfectly with the tree.
Screen, firmware Carried away by the idea to place a display in the mouse, he began to search for it among hundreds of suppliers. The requirements were simple: strict dimensional restrictions and the possibility of at least a symbolic display of at least eight character spaces. While picking up, I learned almost everything about the displays. They differ in types: character and graphics, technology: TAB, COG, TFT, OLED, LCD, E-Paper and others. Each type or technology has a lot of varieties, sizes, colors, lighting, etc. In general, there was something to dig into. Breaking half the Internet, I found out that the size I need is made by only one company in the whole wide world. All other options are clearly larger in size. And even the display I found barely fit inside the mouse. As an option, a custom display was considered, which could be made according to my requirements, but this is a very expensive option for me (about a hundred thousand rubles). For the first model, a 128 x 64 pixel graphic display is fine, which is what I chose. In order to understand how the display really looks and fits with my mouse, I had to order all varieties of this display from manufacturers. What do these varieties mean? The model name consists of alphanumeric unpronounceable combinations like FP12P629AU12. All of them are assembled from various blocks and are clearly deciphered in the specification. For example, the above example can be assembled from blocks FP.12.P.629A.U12, where the type, size, voltage, controller, operating temperature range and other information about the model are encrypted. And the last block is the trickiest. It can have several dozen values, each of which means one or another combination of such characteristics as the presence and color of the backlight, the background color, the color of the characters, the range of degrees from which the information is clearly readable. These are the parameters I was interested in. As a result, "for testing" I ordered 18 different modifications. The manufacturer agreed, but said that the minimum order is 5 displays for each modification. There was nowhere to go, and I had to agree, knowing that 90% would go to the trash can. And on one of the cloudy days, the express delivery service brought me home a huge box in which you can live a bum of average build. There were 18 smaller boxes in the box, each of which freely accommodated 5 displays, securely fixed for a long trip to cold Russia. There was so much accompanying packaging that the mother-in-law was enough to cover several beds for the winter. As a result, after thorough tests on a specially assembled stand, two displays were suitable for the series. They differ only in the background: gray and yellow-green. It is them that I will offer to complete the mouse. By default, I plan to set it to yellow-green, but two more options will be available: a display with a gray background and a mouse without a display at all. But the main intrigue was what information can be shown on the screen? I was offered various ideas: the temperature of the surrounding air, the indication of the arrival of letters, something else not very original. My train of thought went in a different direction. Let's start with the fact that there are two significant limitations to the display of operational information: the presence of a huge and high-quality source of any information (monitor) in front of the user and the need to turn the mouse over to get information. In addition, the screen is small, the resolution is small, the LED interferes with normal reading. Therefore, I came up with one conclusion: information should be only entertaining, the applied value of which tends to zero, but at the same time the WOW!-effect should be lethal. What kind of information can have such properties in a device of ordinary complexity? There is not much of it: mileage, time of use, speed of movement, number of clicks and scrolling of the wheel. I decided to refuse the last parameter, since it seemed uninteresting to me. All other parameters are tied to the session (the last time the mouse was used from the moment it was powered up, that is, connecting to the computer or turning on the computer itself) and to the entire lifetime of the mouse. For example, the user can at any moment of the mouse find out how many times he pressed the left mouse button or how many meters his mouse ran in meters today or since its purchase. The information is absolutely useless, but it will help the especially curious to understand how much he torments the mouse. If other interesting ideas appear, they can be implemented with a new firmware. I also added general information about the mouse (model, mouse and firmware number, month of manufacture) and a settings screen. It will be possible to choose the language and the system of measures (English or metric). To store all this information, a permanent storage flash memory had to be added to the scheme. To fit this amount of information, I had to break everything into screens. Each screen displays one type of information, and shows the values ​​of the parameters for the session and for the entire time. There are six screens in total, which are changed with the mouse wheel. The first option was implemented in a purely textual manner, for which several font options were even developed. I made a firmware to evaluate how the text looks like using the created font on the mouse screen. Looks awful what can I say. Now it has become obvious that graphics are needed on the screen, and not a set of symbolic information. Therefore, I hired a designer to work, and together we prepared three options for graphic design, as a result, the second option was recognized as the most successful. Of course, this design required more resolution, so it had to be adapted. But that's not the end of the story. After I picked up a screen for the mouse, I ordered a trial batch for breadboards. As a result, the screens came, but for some reason the number of outputs differed from what was indicated in the datasheet. In response to a request, the manufacturer received a response that, they say, everything is fine, this is a small modification, and it will not affect performance in any way. Meanwhile, the missing two conductors were responsible for the brightness of the displayed graphics. All this was very suspicious. And just like looking into the water. They redid the board for a modified screen, soldered it, and then it turned out that the screen was completely dim. It's like the batteries are dead. And it turned out after a long and painstaking work on the search and selection of screens, the purchase of a trial batch of all modifications and their testing. Time, money, and so on. But the story had a happy ending. After correspondence with the Chinese, it turned out that the screen can now adjust its contrast directly from the firmware. We treated the firmware, and everything began to show just fine! Everything is shown as planned: mileage, speed, number of clicks, and so on. In the future, the firmware also changed several times: there was a setting for changing the language. Two languages ​​on one screen is bad - readability worsens, the Cyrillic abracadabra will only annoy the English-speaking user, and in the future support for other languages ​​\u200b\u200bis may be needed. Difficulties began when I tried to adjust the mouse travel. It seems that there is something complicated: the optical sensor transmits an increment in two coordinates, which must be brought to a system of measures and added modulo to the current value. That's the whole run. But, as it turned out, not everything is so simple. Two people with mice using the same sensor can get drastically different results! The thing is that the resolution of the sensor (sensitivity) is very dependent on the surface on which the mouse rolls. The best result is obtained when the mouse rolls over white paper. Slightly worse on wood and fabric. On a laminate and a film it is absolutely bad. The declared passport sensitivity is achieved only on ideal, from the point of view of the sensor, surfaces. It doesn't matter to the end user. He connects the mouse and, by trial and error, sets the operating system to a comfortable cursor speed. The system remembers this factor and uses it to increase or decrease the movement coordinate increment values. But it's a completely different matter if you decide to read these parameters directly from the mouse. The mouse on one surface will show the result of a run of one meter, on the other - one and a half. The speed will also "lie". And something needs to be done about it. To solve this problem, it was necessary to introduce the “Discreteness (Sensitivity)” parameter, which allows you to individually select the coefficient for each surface. By default, it is equal to one, which corresponds to the surface of white paper. It can be increased or decreased in the settings. You can not touch it at all, everything will work fine and so. But for true perfectionists, in the leaflet attached to the mouse, a table will be given from which you can select the coefficient for the existing surface and instructions on how you can independently configure the mouse to show the exact mileage. When developing the firmware, another side effect of the sensor was discovered. If you take the mouse and simply wave it in the air, the mileage readings will also change. This is due to the fact that the sensor defines the surrounding space as a kind of surface and also tries to get mouse offset values. Therefore, you can observe the following effect: you turn the mouse over, look at the mileage parameters and are surprised that they change upwards right before your eyes. Of course, you can install a tilt sensor in the mouse that disables the sensor for the time it is turned over, but doing this only for the situation described is unreasonable. Perhaps in the next version it will appear, but not now. After all, the mouse is lifted only to look at the indicators, and 99.9% of the time it is on the surface and receives the correct information.

Cable

I decided to make the cable as flexible as possible so that it does not interfere with the movement of the mouse and is “invisible” for kinematics. Well, I personally do not like the "spring" cable. Sometimes it seems that when creating a product, the cable is the most insignificant part of the product. What is easier - buy the right amount of cable in the store and unsolder it. A trifling matter. But, alas, not here in Russia. Sometimes it seems that our industry is no longer adapted to do anything more complicated than cast-iron irons. Attempts to find a cable resulted in a three-week search and shaking up the assortment of absolutely all manufacturers of Russian cable products. It turned out that our standards do not describe a cable suitable for modern electronic devices. For example, a four-wire microphone cable with a KMM 4x0.12 mm2 braid has an outer diameter of 5 mm. This is a lot. Older mice and keyboards have a seemingly thick cable that is only 3.5mm in outer diameter. The closest analogue on sale was a cable from the German company Lapp Kabel, but it also had an outer diameter of 3.5 mm. Now imagine the braid on such a cable. Represented? I'll tell you that I saw a similar cable on power cords for irons. So, it turned out: you can't buy such a cable in Russia. Dot. Well, we are not accustomed to retreat. I go to production and try to order, since they still make cables in Russia. And for this, let's define my requirements. So, what I need: Cores - copper, braided wires (for flexibility). Number of cores - 4. Screen - yes. Flexibility is maximum. The outer diameter of the cable is strictly no more than 3 mm. Color - Pantone 4625 C. Bottom line: I tried to write off, probably, with a dozen possible manufacturers of cable products, no one is interested in messing with my order. They didn't even ask what mileage I needed. Bottom line: in Russia, such a cable cannot be bought or produced. Sad. But we are not accustomed to retreat. I go to Alibaba.com. I find the first Chinese manufacturer I come across, write a letter and literally in a few hours I get an answer: we will make any cable for you! I'm shocked. I throw him the specification, money for delivery, and a week later I get a sample. Blimey! And I lost almost three months trying to patriotically place an order in Russia. It turned out that the Chinese can quite easily make me a cable with an outer diameter of 2.5 mm. Bottom line: I ordered 4 different samples from China. At first, I was not satisfied with the scratchiness and dullness of the outer sheath, then I was not satisfied with the flexibility of the cable, then again I was not satisfied with the flexibility, and in the end I settled on the last sample sent, which I was ready to order. They can't be more flexible. The cable has memory. As a result, I accidentally received a cable with memory, although I wanted to be as flexible as a rope. I ordered a kilometer, I had the cable in two weeks. Total time spent: six months.
I braided my kilometer of cable. It turned out two options.
Approximately 10% of the cable was discarded. This is the beginning of the bays, where the braid is unraveled and the machine has not yet entered the operating mode. And some places where, for some reason, loops and knots of braiding threads formed. If the end of the cable is not sealed with heat shrink, then it will fluff up at the moment, the threads are synthetic! Therefore, the installation of the cable assembly is hampered by the heat shrink preventive nozzle. The outer diameter of the braided cable turned out to be 3.2 mm, i.e. the braid added 0.7 mm to the cable diameter. It doesn't seem like much, but for a regular mouse, the cable comes mostly with a diameter of 3.5 mm, and in the era of wireless mice it seems thick and heavy. Recently, non-budget mice have begun to be equipped with cables with a diameter of 3 mm, and they no longer interfere with work, they are almost imperceptible. But the keyboard cable can be with an outer diameter of 4 mm. And even more. But for the keyboard it doesn't matter. Next I ordered a cable assembly. The cables are available in two different lengths and two sheath colors. So to speak, for every taste of the consumer.

Plastic parts

As much as I would like to make the body parts of the mouse completely out of wood, plastic is indispensable here. You need legs, an axle for the wheel, a support for the axle and a glass for the display.
Therefore, I had to order a mold from the Chinese.
After each test casting, the Chinese sent me a dozen samples, which I tested on my mouse.
As a result, I finished the mold three times, until the quality began to satisfy me. The problems were different. For example, after assembly, I got the problem of dust that forms between the display and the protective glass. It looks untidy. Moreover, the mouse will scrape over the surface, and dust will gradually accumulate there. I had to convert the glass into a container with sides, where the display will be inserted, after which the circuit will be sealed.
It turned out here is such a detail.
Refining a mold is not an easy task at all, and changes can only be made in the direction of increasing the part. Therefore, any inaccuracy or mistake can spoil the whole work. For reference: each revision is a month and a half of waiting for new samples. And the change itself could be microscopic, but necessary.
I will not dwell on plastic parts, this technology is now in the lead, and I cannot tell you anything new and interesting here. Let me just say about the legs, for which I spent a long time choosing a material with reduced friction, after which I conducted tests and “races” of mice in order to determine the winner with minimal friction.

Processing and coating

First, there is a thorough work with the removal of pile, sanding and polishing the surface.
I had a difficult task ahead of me. It was necessary to stabilize the tree so that the geometry of the mouse does not change depending on the humidity, and protect the tree from working in an aggressive environment (sweat and grease from the hand).
From the very beginning, I refused varnish. Lacquer is a surface film that cracks over time, breaks down, and the tree turns out to be bare. Sweat and grease penetrate into the pores, the wood darkens, and an irreversible process of its degradation begins. Therefore, it was decided to use oil as an impregnation and protection, and wax to give a commercial look.
To make it clear: the tree is completely saturated with pores, which contain either air or the oil of the tree itself (if the tree is rubber). Our task is to fill the pores as much as possible with our oil, which then must polymerize and protect the wood.
In order not to stretch the story, I will say that I have tried many oils: linseed, teak, tung, vaseline, Danish. Each oil has its own character. For example, teak oil is very poorly waxed, and linseed oil takes a very long time to polymerize. Therefore, it is necessary to introduce a catalyst into it - a desiccant.
As a result, I developed two technologies. The first is the technology of vacuum wood impregnation. It works like this: I create a vacuum in an environment with oil and wood. Air begins to come out of the pores. After the vacuum is removed, the pores are filled with oil. As a plus - the tree is well stabilized. As a minus - it is very dark. Looks good, but for an amateur.
The second technology is surface coating with oil. The oil is applied 1-2 or more times with a non-woven cloth.
Then we process with a felt circle.
Apply carnauba wax.
And rub with a muslin circle.
Then, using a mounting hair dryer, I “dissolve” dry wax residues in narrow and difficult places. In the case of "insoluble" debris, I pick up a toothbrush with hard bristles, remove debris and then again locally repeat the procedure for applying wax.
If we evaluate the labor costs of processing, then manual labor per mouse is about four hours.

Assembly

Next comes the installation operation, but before it, you still need to remove traces of processing from the technological holes. Then, using a special 3M tape, I adjust and glue the legs (the case can lead to fractions of a millimeter, and this will be immediately noticeable: it will stagger like a lame stool). Then I lay the cable, mount the board, support, install the wheel and also, if necessary, adjust the buttons (there should be no bounce) and the pressing force. This operation can also take up to four hours.

A mouse is a device that helps the user to work on a computer. When it breaks, many users do not know as far as possible, from the keyboard, they will switch to the desired system icons. This situation leads to the end of the session and the search for service centers for the repair of electronic equipment, or to the acquisition of a new device. If you have such qualities as perseverance, attentiveness, the ability to work with a tester and a soldering iron, then without any problems, based on the information provided, you can quickly determine the cause of the failure of the device and even repair it. Consider repairing a wireless mouse with your own hands.
Causes of breakdown.
Since the mouse is a reliable technique, therefore, in many cases, the breakdown will be insignificant. It can happen due to:
1. Poor contact between the battery and the control board.
2. Failure of one of the electronic components.
3. Damage to the USB port of the computer.
Identification of the cause of the malfunction and methods for its elimination.
To start examining a broken device, it is necessary to disconnect it from the power supply, remove the wireless communication module from the computer's USB and remove the battery. To get to the control board in most models, it is enough to unscrew the fasteners located under the battery and using a flat screwdriver to disconnect the upper part of the case from the latches.

Visually or with a multimeter in the position of checking semiconductor devices, examine the plus and minus marks, connecting wires and soldering points for oxides and mechanical damage. Due to strong vibrations, mechanical stresses, microcracks can occur at the junctions of the elements with the tracks of the board.

To identify them, you need to very carefully examine and shake the fasteners of the wires, the electronic components of the board. When identifying suspicious or defective areas, they should be properly soldered.
If the measures described above did not ensure the restoration of the device's operability, check its resistance on the power terminals. It should be in the range of 400 - 600 ohms. If the ohmmeter shows zero, then there is a short circuit in the electronic circuit, if the unit is open. In these situations, it is necessary to check the electronic components. Detected charred, swollen appliances must be replaced.
To check the health of the photodiode, connect the probe from the “V +” port to its positive input, and the probe from the “COM” port to the negative input. At the same time, the multimeter is switched to the diode test mode. Turn on the phone's camera and point its lens at the photodiode. A healthy element will glow in the displays.

If after all the above measures the mouse does not work, we check the serviceability of the wireless module with a USB plug. With the probe from the “COM” port, touch track 2, and with the other probe, track 1. The readings should be 600 - 800 ohms.

To check the USB port of a computer, it is enough to connect a working device to it, such as a keyboard or a memory drive. If the software responds after connecting, then the port is operational.
In other cases, when the breakdown could not be eliminated, a replacement chip is required.

And although computer mice have evolved significantly since the first appearance of this wonderful device, they still break. Let's talk today about computer mice, or rather about repairing a wireless computer mouse.

For the first computer mice, the most important scourge was the contamination of the very ball that transmits mechanical movement to electronic sensors. Those who remember those times know that it was a dubious pleasure to clean this very ball from dirt. In addition, such a mouse required a rug, otherwise the rubberized ball did not move well on the table.

The time has come and we got rid of this rudiment. Optical mice appeared. Everything would be fine, but the wire with which such an optical mouse was connected to the computer system unit eventually became unusable, and it ceased to obey its owner. The consequences of this could be terrible, up to the complete destruction of a computer mouse on a ruthless brick wall.

But here, too, our botanist friends figured out how to save us from this misfortune - the connecting wire. They began to transmit data from the mouse to the computer via radio waves. Everything would be fine, but the user of such a wireless mouse has to regularly replace dead batteries.

And now, it would seem, all the most malicious attributes have sunk into oblivion: a ball, wires. What's left? Buttons! Yes, yes, it was they who began to break down most often, bringing our favorite computer mouse to complete unavailability. As practice shows, problems with buttons are found not only in cheap models of computer mice, but also in quite branded ones like VAIO.

But, for an avid electronics lover, such a malfunction is not only a challenge to his experience, but also a real opportunity to dig deeper into the insides of this amusing device. Especially if it is not a simple wired mouse, but a wireless one.

So let's get started.

Despite the fact that the development of modern means of input information leads to the disposal of various mechanical devices, computer mice still have buttons in their composition.

On the repair table is a SONY VAIO wireless computer mouse model VGP-WMS4. Diagnosis - incorrect operation of the left mouse button (LMB). Everything else is working properly. The reason is also clear. When working with a computer, we most often use the left button than the right or center button (the one under the wheel).

To open the case, we need a scalpel screwdriver. The screws that hold the case together are located under plastic patches that reduce friction. They need to be carefully peeled off the case and put in a clean place. After the repair, we will glue them to the body again. To unscrew the screws, I had to look for a hexagonal nozzle - the screws have a curly groove.

After opening, the electronic filling appears before us. It was done with dignity. The left and right buttons are three-pin buttons without fixing.

If you carefully remove the scroll wheel, then under it we will find a micro button. This is what we press when we click on the wheel - this is the third, central input button.

Let's digress from the repair and at the same time study the device of a wireless computer mouse. As you can see in the photo, several microcircuits are installed on the main board. The one in a square case is more likely responsible for wireless data transmission. The antenna is clearly visible on the printed circuit board, which is made in the form of copper tracks directly on the printed circuit board.

An open optocoupler acts as a rotation sensor for the central wheel. The optocoupler consists of an infrared LED - the one in a transparent case and with two leads, as well as a phototransistor. It has a dark body and three pins.

There are through grooves in the wheel.

When the wheel moves, the through grooves are replaced by partitions. As a result, infrared radiation either passes or does not pass through the wheel base. The received signals from the phototransistor are sent to the microcontroller, which processes the received data.

Also in the case you can find an optical system. It consists of a bright LED, a lens system and a photo sensor.

All computer mouse electronics are powered by two AA (1.5V) alkaline batteries. Moreover, for the operation of the mouse, both the voltage of 1.5V and 3V is removed. A connecting wire extends from the middle contact in the battery compartment. Most likely, 1.5V from one battery is used to power the controllers, while 3V is used to power other parts of the circuit, such as the bright red LED that is part of the optical system of the reader.

Let's get back to repairing our computer mouse. Finding the right replacement button can sometimes be difficult. But that's not a problem. You can use another computer mouse as a "donor". As a rule, the right key button for many of them is working, and it can be used as a replacement. An optical wired mouse was used as a donor mouse. At one time, she also died a heroic death after numerous attempts to restore the connecting wire. After a short "tail" remained from the wire, she flew off to the storeroom.

Let's take a look at her device. As we can see on the printed circuit board, we already know the buttons, the scroll wheel, the photosensor (a microcircuit in the middle of the board), the LED and the controller chip. It is worth noting that in this computer mouse, not an optocoupler, but a multi-turn encoder is used as a scroll wheel sensor.

This is not buzzing, since the encoder is an electromechanical part. And, as you know, everything mechanical is subject to wear. In a VAIO mouse, the optocoupler will work more reliably - after all, there are no mechanical contact parts in the optocoupler.

As already mentioned, it is better to use the right button as a replacement button.

Here is the result of replacing the failed button.

It is also worth recalling that when restoring the operation of the mouse, it is worth cleaning the scroll wheel, optical system and the case itself from dust. Since the computer mouse contains optical sensors, such prevention will have a positive effect on its operation.

Computer mouse- This is an electronic manipulator designed to remotely control the operation of computer programs by activating the cursor moving across the monitor screen following the movement of the mouse over the surface. For control, at least two keys and a wheel are installed on the mouse body, allowing you to scroll pages in the vertical direction.

According to the method of connecting to a computer, mice are wired (connected using a flexible cable with a PS / 2 or USB connector) and wireless.

The photo shows a wireless mouse. As you can see, it does not have a wire to connect to a computer. In wireless mice, information is exchanged using radio frequency. A transceiver is inserted into the USB port of a computer, laptop or tablet, which provides two-way communication between the mouse and the device via the air.

Wireless mice have the following disadvantages: - they are more expensive, heavier and require additional attention, as it is necessary to periodically replace dead batteries or recharge the batteries.

Optical computer mice are very reliable and can last for many years. But over time, they break down, and you have to replace the mouse or repair it yourself, since repairing in the workshop will cost more than the cost of a new one.

Wired mice fail, in the vast majority of cases, due to chafing of the wire at the point of exit from the case, and wireless ones due to the discharge of the battery, accumulator or contact failure between its terminals or contacts in the container due to their oxidation. Over time, any mice fail due to the wear of the buttons, usually the left one, as the most frequently used. For repair, the mouse must be disassembled.

How to disassemble a computer mouse

In order to disassemble the mouse for repair, you need to unscrew the mounting screws from its bottom side. Usually there is one, but there may be several. In this mouse model, the body halves are fastened with one screw.

If the screws are not visually visible, then most likely they are covered with a label or hidden under the thrust bearings. You need to lightly press on the label over the entire area. If, in some place, the label bends in the shape of a circle, then, most likely, the screw is hidden there. In this mouse, the screw is hidden under the label, which had to be partially peeled off.

In the model, for example, TECH X-701, the fastening is made with the help of two screws, one of which is also hidden under the label. When trying to peel off the label, it began to tear, I had to unscrew the screw, making a hole in the label. The place where the label was punctured with a screwdriver in the photo below is indicated by a blue circle.

If it was not possible to find screws under the labels, then they are definitely sealed with thrust bearings. For access, you need to carefully remove the thrust bearings with a knife. At the end of the repair of the mouse, they will need to be glued in place, since without thrust bearings it will slide worse on the rug.

After unscrewing the screws, you need to push the halves of the mouse body from the side of the unscrewed screw in different directions and remove the upper part, on which the buttons are located.

The printed circuit board of the mouse is usually not fixed with screws and is installed with holes on plastic rods protruding from the case. But there are computer mice in which the printed circuit board is screwed to the body with small screws. If, when trying to remove the board, it does not lend itself, you need to find and unscrew all the screws that secure it. An example of this is the TECH X-701 computer mouse, which is fixed to the case with a screw that simultaneously fixes an additional printed circuit board of the side buttons.

To remove the board, you need to pry it from below, while simultaneously removing the axle of the wheel from the bearing retainers of the housing.

When disassembling the mouse, remember how the parts are located relative to each other. Pay special attention to the wheel ratchet spring (if any). It looks like a clothespin spring, only small in size and can be easily lost. If you don't like how the ratchet works when turning the wheel, you can slightly bend the tip of the spring that comes into contact with the teeth of the wheel. The pressure will decrease and the wheel will turn more smoothly.

When disassembling and repairing the mouse, care must be taken not to allow hands to touch the surfaces of the optical prism and other optical elements. If they accidentally touched and there were traces of sweat and grease on the surface, then they must be removed with a napkin impregnated with a special composition for wiping optical parts. Under no circumstances should any solvents be used for cleaning. If you don't have a special cloth handy, simply wipe away any traces of dirt with a soft, clean cloth.

Wireless mouse repair

The main reason for the complete inoperability of wireless mice is dead batteries (accumulators) or poor contact of their terminals with the electrical circuit of the mouse. Since the lasers of many models of mice operate in the light range, it is enough to turn on the mouse and look at it from below to determine the condition of the batteries. If a red glow is emitted, then the batteries are good. Otherwise, the repair should begin with checking the batteries and the quality of their contact with the electrical circuit of the mouse.

In order to get to the batteries, you need, for example, as in this mouse, press the "Open" button, after which the battery cover will be released and it will open.

If the laser in the mouse works in an invisible zone, then you can check the state of the power source only by replacing or measuring the voltage at the battery terminals.

In a mouse that has been working for a long time, the contacts on both the battery terminals and the contacts in the mouse can oxidize. In this case, they need to be inspected and, if oxides are found, remove them with a rag soaked in alcohol or simply rub them well to a shine. It is undesirable to remove oxide from the mouse contacts with sandpaper, as a thin protective galvanic coating will be removed from them.

Like a wired mouse
repair frayed wire

If, when using the mouse, the cursor began to spontaneously move, jump to any place on the monitor screen or freeze, then with greater certainty it can be argued that the integrity of the wire was broken at the exit from the case. It is easy to check this, you need to press the wire to the case, and if the working capacity is temporarily restored, then it’s definitely the wire.

If, when examining the wire at the point of exit from the computer mouse case, its physical damage is detected, then the reason for the inoperability is obvious. Here is an example of such damage. The photo shows that the double outer sheath of the wire is damaged, and some conductors of the tinsel type are frayed.

With the skills of soldering with a soldering iron, a computer mouse with a frayed wire is not difficult to repair, doubling its service life. Repair consists in removing the damaged section of the wire and soldering, newly prepared ends of the surviving part of the conductors into the printed circuit board.

How to repair a frayed mouse wire by soldering

The wire connecting the computer mouse to the connector can be of two types - made of an ordinary thin stranded copper wire and a tinsel-type wire. Tinsel-type wire is more elastic, therefore it has high bending resistance and lasts longer.

Entering the mouse body, the wire runs along and connects to the printed circuit board. There are two types of connections, a detachable connection or by pressing into a block that is soldered into the board. The photo shows a block soldered from a printed circuit board with conductors pressed into it.

Regardless of the method of connecting the wires to the printed circuit board of the mouse, in order to know how to solder during repairs, you need to photograph or draw what color the wire is connected to which contact. Then remove the connector from the board (it is better not to disconnect, it is easier to solder) or the block. There is no international standard for the color scheme of mouse wires, and each manufacturer chooses the color of the wires at their own discretion. I had to repair many computer mice and everywhere the wires from the same connector pins came in different colors. Obviously, this is due to the fact that the mouse is considered a consumable item, and manufacturers do not provide for its repair after the end of the warranty period.

After desoldering the old wires from the mouse circuit board, you need to free the holes from the solder to solder the new wires. This work is easy to do with a toothpick or sharpened match. It is enough to heat the solder at the location of the hole on the side of the printed conductors of the board and insert the tip of the toothpick into it, remove the soldering iron, and when the solder hardens, remove the toothpick. The hole will be free for the conductor to be inserted into it.

To prepare the wires for installation, it is necessary to cut off the worn-out piece of wire 15-20 mm long that comes out of the mouse body. Remove the insulation from the wires and solder the ends of the conductors. You need to tin the wires by placing them on a wooden stand, while rotating in one direction, so that the tinned ends of the wires turn out to be round. Otherwise, they will not be able to be inserted into the PCB holes.

Insert wires into the printed circuit board of the mouse, in accordance with the sketched color scheme and solder with a soldering iron.

Tinsel-type wires cannot be tinned with ordinary rosin flux, since the tinsel ribbon conductors are covered with a layer of insulating varnish. Acid flux should not be used, as it will impregnate the inner thread of the tinsel wire and destroy the conductors over time. The best flux in this case is an aspirin tablet.

It remains to insert the tinned ends of the wires into the holes of the printed circuit board and solder them with solder.

Sometimes there are mice in which the printed circuit board is double-sided with holes for wires of a very small diameter, and it is very difficult to free them from solder. In this case, you can simply solder the conductors to the pads. Since no physical load is applied to the wires during mouse operation, the connection is quite reliable.

Now you can install the printed circuit board in the base of the case and fix it with a screw, lay the wire and close the top cover. When installing the cover with buttons, make sure that the wire does not get under the pushers of the buttons, between the mating protrusions of the housing and does not touch other moving parts. Before assembling the mouse, it is imperative to remove dust and hairs, which, over a long period of operation, fill up through the gap between the wheel and the body quite a lot. The repair is over and the computer mouse is ready for work again.

How to repair a frayed mouse wire with a twist

It’s more reliable than soldering to repair the wire, but not everyone knows how to solder, and if they do, they don’t always have a soldering iron at hand. With success, you can restore the operation of the mouse without a soldering iron, by twisting the wires. The mouse is disassembled and a section of frayed wire is cut out.

The conductors are carefully removed from the cut wire sheath. The sheath of the wire is not cut, it will still serve.

The length of the conductors is adjusted in such a way that, when twisting, the twisting points are shifted relative to each other by 8 mm and the ends of the conductors are stripped of insulation to a length of 5-8 mm.

The ends of conductors of the same color are tightly twisted together.

The resulting twists are bent along the conductors, and the conductors are tucked into one of the previously cut wire sheaths. When refueling, you need to pay attention so that the twists do not touch each other.

A couple of turns of insulation will prevent the twists from accidentally touching the parts on the mouse board and will give the connection sufficient mechanical strength.

It remains to insert the wire connector into the mating part on the printed circuit board of the mouse and lay the wire in the case.

Close the top cover, tighten the screws and you can start working on the computer. A wire repaired in this way will last another lifetime. Sometimes the system unit is installed away from the workplace, and the length of the mouse wire is not enough to work without tension. Using the above technologies, you can successfully extend the wire to the desired length by taking the wire from the old mouse. Since there is no single color standard for wires, you must first determine by dialing which color of the wire is connected to which number in the connector.

To increase the service life of the mouse, it is necessary to ensure that the wire at the point of exit from the body of the mouse does not bend much during manipulations.

If the mouse wheel does not rotate well

Sometimes when the mouse wheel is rotated, page scrolling is jerky or does not move to one side. One of the reasons is the ingress of dust and hairs between the photo sensor and the photo sensor of the optocoupler of the wheel. Dirt enters the mouse body through the gap between the mouse body and the wheel and sticks to the wheel axles, as they are coated with grease to improve glide.

After removing dust and hairs, the performance of the mouse wheel was restored.

Mouse button repair

If when you click on the left or right mouse button, the reaction does not always occur or does not occur at all, then there may be two reasons. Wear of the button at the point of contact with the pusher of the microswitch or its failure. In order to understand the reason, it is enough to disassemble the mouse and inspect the place of the button in contact with the pusher. If there is a millimeter deepening, then perhaps this is the reason.

When you press a finger on the pusher of a working button, a clear and sonorous click should be heard. If the sound is muffled, then the switch may be the problem. To check, you need to connect the mouse with the upper half removed to a working computer and press the pushers of the microswitches with your finger. If it works normally, then it will be enough to eliminate the production on the button in any way possible, for example, by melting plastic, a drop of epoxy. If it's the microswitch, you'll have to replace it.

The vast majority of mice use microswitches of standard sizes. The microswitch is arranged and operates as follows. In a plastic case, three brass plates of complex configuration are pressed, which end with pins for soldering into a printed circuit board. The left (pictured) plate is the middle point of the switch. An additional thin brass plate with a U-shaped hole is fixed on it in a spacer.

On the left side, a thin brass plate is hooked on the ledge on the left side of the left contact plate, and on the right side, with a curved arc, it is hooked on the right ledge of the left contact plate. A thin flat plate is installed in such a way that its right end always pushes up, and it is in contact with the right thick L-shaped plate.

When you press the button, the button pusher transmits force to a thin plate, it moves down, moves away from the upper contact and comes into contact with the lower one, the output of which is in the middle of the button. After the cessation of pressure, a thin plate returns to its upper starting position and again connects the extreme contacts of the microswitch. Thus, when the button is not pressed, the extreme contacts coming out from the bottom of the button are connected to each other, and when pressed, the left and middle contacts are connected to each other.

Over time, the metal accumulates fatigue, the arcuate spring deforms and partially loses its springy properties. This is where the button stops working. You can try to repair the microswitch, for which you can disassemble it, remove the arcuate spring and straighten it a little. But having a stock of old mice, I did not have to resort to such repairs. Although the buttons in keyboards were repaired many times in the early days of computers, each button in them worked on the same principle as microswitches in mice.

Therefore, if you have an old ball valve lying around, then it is more expedient to remove the microswitch from it to replace the failed one. It is best to solder the one that is installed under the wheel. It is rarely used and is usually serviceable.

If there is no wheel, then take the microswitch of the right button. Before soldering the microswitch, pay attention to how it is installed. In microswitches, the pins are arranged symmetrically and it is easy to make a mistake during installation. If there is no old mouse, then it is permissible to swap the microswitches in the mouse being repaired, from under the left button to the one installed under the wheel. And if there is a completely hopeless situation, then you will have to repair the microswitch.