JP4048548B2 - Manufacturing method of key switch - Google Patents

Description

  The present invention relates to a key switch for a keyboard input device, and more particularly to a method of manufacturing a key switch suitable for use in a keyboard input device of a portable personal computer such as a notebook personal computer or a mobile.

  Recently, a demand for thinning a keyboard input device of a portable personal computer such as a notebook personal computer or a mobile has become stronger. For example, Japanese Patent Application Laid-Open No. 6-260053 shows in FIG. Such key switches have been proposed. In this device, a plate-like holder 2 is superposed and fixed on a flexible circuit board (switch board) 1 having a movable contact, and a key is placed on the upper part of a pantograph assembly (guide support member) 3 supported on the lower part of the holder 2. Top 4 is installed.

  The pantograph assembly 3 includes two hinge members (movable members) 5 and 6 whose intermediate portions are hinged so as to form an X shape. Both the movable members 5 and 6 each have one end portion as a holder. 2 and the gripping portions 2a and 4a provided on the key top 4 are rotatably supported, and the other end portions thereof are slidable on sliding step portions 4b and 2b provided on the key top 4 and the holder 2. It is supported. The key top 4 is normally positioned at the rising end shown in the figure by receiving the biasing force of the rubber spring 7 protruding from the opening of the holder 2 and surrounding the movable contact through the pantograph assembly 3. When the key top 4 is pushed in from the state, the pantograph assembly 3 is folded, the rubber spring 7 is crushed, and the movable contact is closed. That is, by installing the pantograph assembly 3 between the holder 2 and the key top 4, the installation height of the key top 4 can be made as low as possible, and the keyboard input device is made thinner accordingly. Will do.

  By the way, the above-described key switch has a low manufacturing cost, and a good sliding feeling can be obtained between the holder 2 and the key top 4 and the pantograph assembly 3. At first, all the elements such as the key top 4 and the movable members 5 and 6 were made of resin. In this case, due to strength restrictions and restrictions around the resin at the time of molding, there is a limit to making the holder 2 particularly thin (about 1 mm is a limit), and if the sandwiching part 2a and the sliding step part 2b are included, The holder 2 has a considerable thickness as a whole, and there is a problem in that it cannot meet the demand for further thinning of the keyboard input device.

  In addition, although the thickness can be reduced by making the holder 2 made of metal, in this case, the two movable members 5 and 6 constituting the pantograph assembly 3 are in metal contact with the holder 2. In addition, the sliding feeling is deteriorated, and moreover, complicated processing for forming the sandwiching portion 2a and the sliding step portion 2b is required, so that the manufacturing cost is greatly increased and the fundamental solution cannot be achieved. There is also a way of thinking that the holder is divided structure, the sandwiching part 2a and the sliding step part 2b are molded with resin, and these are assembled to the metal plate. However, depending on the divided structure, the assembly of the holder itself becomes troublesome. , At the expense of productivity.

  The present invention has been made in view of the above-described conventional problems, and an object of the present invention is to make the holder without sacrificing sliding feeling or causing an increase in manufacturing cost or a decrease in productivity. An object of the present invention is to provide a key switch manufacturing method that can reduce the thickness of the device.

  In order to achieve the above object, the first invention is a method in which a plate-like holder is superposed and fixed on a switch board, and a key top is attached to an upper part of a pantograph assembly whose lower part is supported by the holder via a mounting plate. In a key switch manufacturing method in which the key top is always lifted by the biasing force of the rubber spring and the contact is closed in response to the key top being pressed, the metal support plate is turned upside down. A subframe in which the mounting plate is integrated with a pantograph assembly in which two movable members are connected by a hinge after a support frame made of resin is mounted on an upright piece formed in advance on the opening edge of the support plate and the holder is assembled. Push the assembly body into the opening of the holder, and then superpose and fix the switch board on the support plate while protruding the rubber spring from the opening of the holder , Thereafter, the holder is inverted, characterized in that to push integrating the key top with respect to the mounting plate.

  In the key switch manufacturing method performed in this way, the holder is composed of a metal support plate and a resin support frame disposed along the opening edge of the support plate. The holder can be made thinner as compared with the case where the whole is made of resin. Further, since the support frame, the pantograph assembly, and the key top are all made of resin, good sliding feeling is ensured between the holder, the key top, and the pantograph assembly. Moreover, since the assembly can be performed simply by placing the support frame on the upright piece formed on the opening edge of the support plate, the assemblability of the holder itself is not deteriorated.

  In order to achieve the above object, the second invention is a method in which a plate-like holder is superposed and fixed on a switch board, and a key top is attached to the upper part of a pantograph assembly whose lower part is supported by the holder via a mounting plate. In the key switch manufacturing method in which the key top is always lifted by the biasing force of the rubber spring and the contact is closed in response to the pressing of the key top, the key top is mounted in the reverse direction on the tray mounting portion. After placing the metal support plate constituting the holder on the tray in the reverse direction, the key top hook is positioned in the opening of the support plate, and then the resin support frame constituting the holder is placed. A holder is assembled by placing it on an upright piece formed in advance on the opening edge of the support plate, and then a pantograph assembly in which two movable members are coupled by a hinge, and the mounting plate The integrated subassembly body is pushed into the opening of the holder in advance of the mounting plate, and the key top is integrated with the mounting plate of the subassembly body, and then the rubber spring protrudes from the opening of the holder. The switch substrate is aligned with a support plate while the switch substrate is overlapped and fixed to the support plate.

  In the key switch manufacturing method performed in this way, in addition to the operation of the first aspect of the invention, the assembling is completed only by one-way work, which is useful when a large number of key switches are automatically assembled.

  According to the method for manufacturing a key switch according to the present invention, the holder can be thinned without sacrificing the sliding feeling or increasing the manufacturing cost or reducing the manufacturing cost. This is extremely useful for reducing the thickness.

The best mode for carrying out the invention will be described below with reference to the accompanying drawings.
1 to 3 show one embodiment of the present invention. This key switch includes a switch board 10 provided with a plurality of rubber springs 11 surrounding a movable contact (described later) (FIG. 3), and a rectangular opening that is overlapped and fixed on the switch board 10 and through which the rubber springs 11 are inserted. , A pantograph assembly 30 having a lower part supported by the plate holder 20, and a key top 50 attached to the upper part of the pantograph assembly 30 via a mounting plate 40. Has been.

  As shown in FIG. 3, the switch substrate 10 has a membrane sheet 13 disposed on a flat plate 12 made of metal (usually made of aluminum). The membrane sheet 13 isolates the contact substrate 15 having the wiring 14 formed on the surface, the insulating movable plate 17 having the movable conductor 16 formed on the back surface, and the contact substrate 15 and the movable plate 17 at a slight interval. The rubber spring 11 is disposed at a position surrounding the back side of the movable conductor 16. The rubber spring 11 is normally extended to maintain the illustrated dome shape, and in this state, the movable conductor 16 is separated from the wiring 14 and the movable contact is maintained in an open state. Then, when the rubber spring 11 is crushed from this open state, the protrusion 11a existing inside the top part pushes down the movable plate 17, so that the movable conductor 16 contacts the wiring 14 and the movable contact is closed. Become. When the pressing force to the rubber spring 11 is released, the restoring force returns to the illustrated state.

  The holder 20 includes a flat plate-like support plate 22 having the opening 21 and a U-shaped support frame 23 disposed in the opening 21 of the support plate 22. Here, the support plate 22 is made of an extremely thin (about 0.2 mm) stainless steel plate, and a plurality of upright pieces 24 that incline upward toward the opening are integrally formed at the edge of the opening 21. Has been. On the other hand, the support frame 23 is integrally formed from a resin, and a fitting groove 25 that allows the upright pieces 24 to be fitted is formed on the outer peripheral surface thereof. The support frame 23 is positioned front and rear, left and right in the opening 21 by fitting the upright piece 24 into the fitting groove 25, and is sandwiched between the upright piece 24 and the switch board 10. Has been. The support frame 23 is also formed with a pair of clamping portions 26 and a pair of sliding step portions 27 that support the lower part of a pantograph assembly 30 described in detail later on the inside of the left and right leg pieces.

  The pantograph assembly 30 is formed by hinge-joining two frame-shaped movable members 31 and 32 integrally formed from resin so as to form an X shape. More specifically, the hinge pin 33 can be fitted into the left and right frame pieces of one movable member (first movable member) 31, and the hinge pin 33 can be fitted into the left and right frame pieces of the other movable member (second movable member) 32. Each pin hole 34 is provided. Further, most of the first movable member 31 excluding the base end portion is formed to be narrower than the interval between the left and right frame pieces of the second movable member 32. The first movable member 31 and the second movable member are inserted into the pin hole 34 while the two movable members are bent with each other while the movable member 32 is positioned inside the second movable member 32. 32 are coupled to each other so as to be rotatable.

  The base end portion of the first movable member 31 constituting the pantograph assembly 30 is formed wide, and sandwiched portions of the support frame 23 constituting the holder 20 are formed at the left and right corners of the base end portion. A second hinge pin 35 that can be fitted to the H. 26 is protruded. The sandwiching portion 26 has a deformed groove shape with the back surface side of the support frame 23 wide (FIG. 1), and the first movable member 31 is moved upward from the back surface side of the support frame 23 so that the first The second hinge pin 35 is locked to the holding portion 26. On the other hand, the second movable member 32 constituting the pantograph assembly 30 is provided with a sliding pin 36 projectingly engaged with the sliding step portion 27 of the support frame 23 at the left and right corners of one end thereof. Yes. The sliding pin 36 is locked to the sliding step portion 27 by moving the second movable member 32 upward from the back surface side of the support frame 23. Thus, in the final assembly state, the back side of the sandwiching portion 26 and the sliding step portion 27 is closed by the switch substrate 10, and thus, the sandwiching portion 26 and the switch substrate 10 are separated from each other. A bearing portion 37 that rotatably supports the second hinge pin 35 on the proximal end side of the first movable member 31 is formed between the sliding step portion 27 and the switch substrate 10. In between, a sliding guide groove 38 for slidingly guiding the sliding pin 36 of the second movable member 32 is formed in cooperation.

  The mounting plate 40 is provided with support portions 41 and 42 that are stepped down at both ends thereof. Of these support parts, the support part 41 on one end side is a frame piece (shaft piece) 31 a on the tip end side of the first movable member 31, and the support part 42 on the other end side is other than the second movable member 32. The frame piece (shaft piece) 32a on the end side serves to lock each, and the support portion 41 on one end side has a considerable length, whereas the support portion 42 on the other end side has a considerable length. The shaft piece 32a has a minimum length necessary to support the shaft piece 32a. On the other hand, hooks 51 and 52 that can be engaged with the support portions 41 and 42 at both ends of the mounting plate 40 protrude from the back surface of the key top 50. The key top 50 is detachably coupled to the mounting plate 40 by hooking the support portions 41 and 42 of the mounting plate 40 to hooks 51 and 52 at both ends thereof. Thus, in this coupled state, a slide for guiding the shaft piece 31a on the distal end side of the first movable member 31 to slide between the support portion 41 on one end side of the mounting plate 40 and the key top 50 is provided. A movement guide groove 43 is formed in cooperation, and on the other hand, the shaft piece 32a of the second movable member 32 is rotatable between the support portion 42 on the other end side of the mounting plate 40 and the key top 50. A bearing portion 44 that supports the joint is formed in cooperation. Note that the mounting plate 40 and the key top 50 are each integrally formed from a resin, and both of them are fitted into a positioning hole 45 formed in the center of the mounting plate 40 with a positioning split pin 53 protruding from the back surface of the key top 50. By combining, they are positioned relative to each other.

  In order to assemble the key switch, first, the first movable member 31 and the second movable member 32 are integrated using the hinge pin 33 and the pin hole 34 respectively provided to obtain the pantograph assembly 30. . Next, the shaft piece 31a of the first movable member 31 is placed on one support portion 41 of the attachment plate 40, and the shaft piece 32a of the second movable member 32 is bent while the other piece of the attachment plate 40 is bent. The sub-assembly body of the pantograph assembly 30 and the mounting plate 40 is obtained. On the other hand, the holder 20 holds the support plate 22 upside down and holds the support plate 23 at a predetermined height, and the support frame 23 is fitted to the upright piece 24 while fitting the fitting groove 25 of the support frame 23 into the upright piece 24. Place it. Under this state, the sub-assembly body of the pantograph assembly 30 and the mounting plate 40 is pushed through the opening 21 of the holder 20. Then, the second hinge pin 35 of the first movable member 31 constituting the pantograph assembly 30 is hooked on the holding portion 26 of the support frame 23, and the slide pin 36 of the second movable member 32 is attached to the support frame 23. It catches on the sliding step 27.

  Thereafter, the switch substrate 10 is superposed and fixed to the support plate 22 of the holder 20 while the rubber spring 11 is projected from the opening 21 of the holder 20. Then, the bearing portion 37 and the sliding guide portion 38 are formed in cooperation between the support frame 23 and the switch substrate 10, and the first movable member 31 constituting the pantograph assembly 30 is formed on the bearing portion 37. The lower end portion (second hinge pin 35) is rotatably supported, and the lower end portion (sliding pin 36) of the second movable member 32 is slidably supported by the sliding guide portion 38. At the same time, the urging force of the rubber spring 11 is applied to the mounting plate 40, the pantograph assembly 30 is extended, and the mounting plate 40 is lifted from the holder 20. At this stage, when the holder 20 is reversed and the key top 50 is pushed into the mounting plate 40 from above while aligning the split pin 53 and the positioning hole 45 of the mounting plate 40, the hooks 51, 52 of the key top 50 are placed. The tip portions of the support portions 41 and 42 of the mounting plate 40 are hooked, and the key top 50 is integrated with the mounting plate 40. As a result, the sliding guide portion 43 and the bearing portion 44 are formed in cooperation between the mounting plate 40 and the key top 50, and the upper end portion (the shaft) of the first movable member 31 is formed on the sliding guide portion 43. The piece 31a) is slidably supported, and the upper end portion (the shaft piece 32a) of the second movable member 32 is rotatably supported by the bearing portion 44, whereby the key switch is completed.

  In this key switch, the holder 20 is formed of a metal support plate 22 and a resin support frame 23 that supports the lower part of the pantograph assembly 30, so that a thin plate can be used as the support plate 22. The holder 20 can be made thinner as compared with the case where the whole is formed of resin. In addition, since the support plate 22 has a simple flat plate shape, an increase in manufacturing cost is slight. Further, since the assembly can be performed simply by placing the support frame on the upright piece integrally formed on the opening edge of the support plate, the assembly of the holder 20 itself does not deteriorate. The support frame 23 includes a holding portion 25 that rotatably supports a lower end portion of one movable member 31 of the pantograph assembly 30 arranged in an X shape, and a lower end portion of the other movable member 32 of the pantograph assembly. Since the pantograph assembly 30 is moved in one direction through the opening 21 of the holder 20, the lower portion of the pantograph assembly 30 is attached to the support frame 23. The pantograph assembly 30 can be easily assembled. Furthermore, since the key top 50 is detachably mounted on the pantograph assembly 30 via the mounting plate 40, the entire key switch can be easily assembled.

  In the thus completed key switch, when the key top 50 is depressed, the first and second movable members 31 and 32 constituting the pantograph assembly 3 swing around the bearing portions 37 and 44, respectively. The pantograph assembly 30 is folded and the rubber spring 7 is crushed, and as a result, the movable contact in the switch board 10 is closed. . On the other hand, when the pressing force to the key top 50 is released from this state, the first and second movable members 31 and 32 swing again around the bearing portions 37 and 44 by the restoring force of the rubber spring 11, One end of each slides again along the sliding guides 43 and 38, the pantograph assembly 30 expands, and the key top 50 returns to the original state shown in FIG. The contact opens. Thus, the first and second movable members 31, 32, the mounting plate 40, and the key top 50 constituting the pantograph assembly 30, including the support frame 23 of the holder 20 that provides the sliding guide portions 43, 38, are provided. Since it is made of resin, good sliding feeling is ensured between the pantograph assembly 30, the holder 20, and the key top 50.

Here, since the keyboard input device is equipped with a large number of key switches, for example, the following assembling procedure is adopted in order to incorporate the necessary number of key switches at once.
That is, a tray (not shown) having a required number of key top 50 mounting portions is prepared, and the key tops 50 are mounted in opposite directions on the mounting portions of the tray. Next, the support plate 22 constituting the holder 20 is placed on the tray in the reverse direction, and the hooks 51 and 52 of the key top 50 are positioned in the opening 21 of the support plate 22. This is placed in the opening 21 of the support plate 22 and placed on the standing piece 24 of the support plate 22. On the other hand, a sub-assembly body in which the pantograph assembly 30 and the mounting plate 40 are integrated separately is prepared, and each sub-assembly body is pushed into the opening 21 with the mounting plate 40 in advance, and a support portion of the mounting plate 40 is provided. The hooks 51 and 52 of the key top 50 are engaged with 41 and 42 so that the key top 50 is integrated with the subassembly body. At this time, the hinge pin 35 of the first movable member 31 and the slide pin 36 of the second movable member 32 of the pantograph assembly 30 are engaged with the holding portion 25 and the sliding step portion 26 of the support frame 23, respectively. . Thereafter, the switch board 10 is aligned with the support plate 22 while the rubber spring 11 is pushed into the opening 21, and the switch board 10 is overlapped and fixed to the support plate 22 by an appropriate fixing means. The assembly of each key switch is completed.

  The keyboard input device thus completed has a thin holder 2 due to the use of a metal support plate 22, so that it is thin as a whole and is suitable for use in portable personal computers such as notebook computers and mobile devices. It becomes. Moreover, since the membrane sheet 13 is sandwiched between the existing metal flat plate 12 on the back side and the metal support plate 22 on the front side, the ground surface is doubled and electrostatic breakdown (ESD) is performed. ) Are sufficiently protected from the viewpoint of durability and reliability.

It is sectional drawing which shows the structure of the key switch assembled by the manufacturing method which concerns on this invention. It is a disassembled perspective view of the key switch shown in FIG. FIG. 2 is a cross-sectional view showing a structure of a switch board constituting the key switch shown in FIG. It is sectional drawing which shows the structure of the conventional key switch.

Explanation of symbols

DESCRIPTION OF SYMBOLS 10 Switch board 11 Rubber spring 13 Membrane sheet 20 Holder 21 Opening 22 Support plate 23 Support frame 24 Standing piece 26 Holding part 27 Sliding step part 30 Pantograph assembly 31, 32 Movable member 31a, 32a Shaft piece 35 Hinge pin 36 Slide pin 40 Mounting plate 41, 42 Mounting plate support 50 Key top 51, 52 Key top hook

Claims (2)

  A plate-like holder is superposed and fixed on the switch board, and a key top is attached to the upper part of the pantograph assembly whose lower part is supported by the holder via a mounting plate. In the manufacturing method of the key switch that closes the contact in response to the depression of the key top, the resin is applied to the standing piece formed in advance on the opening edge of the support plate in a state where the metal support plate is turned upside down. After the support frame is placed and the holder is assembled, a sub-assembly body in which the pantograph assembly in which two movable members are coupled by a hinge and the mounting plate is integrated is pushed into the opening of the holder, The switch board is superposed and fixed to the support plate while the rubber spring protrudes from the opening of the holder, and then the holder is inverted and moved forward. Method for producing a key switch, characterized in that to push integrated key top relative to the mounting plate. A plate-like holder is superposed and fixed on the switch board, and a key top is attached to the upper part of the pantograph assembly whose lower part is supported by the holder via a mounting plate, and the key top is always lifted by the urging force of the rubber spring. And a metal that constitutes a holder on the tray after the key top is placed in the reverse direction on the tray placing portion in the method of manufacturing the key switch that closes the contact in response to the depression of the key top. Put the support plate in the opposite direction, place the hook of the key top in the opening of the support plate, and then place the resin support frame that constitutes the holder on the standing piece formed in advance on the opening edge of the support plate After mounting the holder and assembling the holder, a sub-assembly body in which the pantograph assembly in which the two movable members are coupled by a hinge and the mounting plate is integrated is removed. First, the plate is pushed into the opening of the holder, the key top is integrated with the mounting plate of the subassembly body, and then the switch board is aligned with the support plate while the rubber spring protrudes from the opening of the holder. A method for manufacturing a key switch, characterized in that the switch substrate is superposed and fixed to a support plate.

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