JPH043370Y2 - - Google Patents

Description

[Detailed description of the invention] [Field of industrial application] This invention relates to a push switch.

[Prior art]

For example, a push switch used in electronic equipment such as a cassette tape recorder has a case with a plurality of contact electrodes arranged on the inside surface, and a knob that is movable up and down inside the case and is inserted into the case from a protruding opening provided on the top of the case. a movable body that is pushed down by a push operation of an operating knob protruding from the case and returned upward by a return spring provided in the case; This push switch is generally attached to a wiring board and incorporated into electronic equipment.

[Problem that the invention attempts to solve]

By the way, electronic devices such as the above-mentioned cassette tape recorders are assembled by attaching various parts to the wiring board, cleaning the entire board with a volatile cleaning solution such as Freon, and then putting it into a cabinet. However, conventional push switches do not have a watertight structure where the operating knob protrudes, so if you attach the push switch to the board and then wash the board, cleaning fluid may get into the push switch during cleaning. Conventionally, it was thought that the only way to install a push switch was after cleaning the circuit board.

This is because the case of the push switch is provided with a knob protrusion opening on the top surface of the case to allow the operation knob of the moving body to protrude above the case. In this case, when the substrate is being cleaned by placing it in the cleaning liquid, the cleaning liquid will enter the case through the gap between the knob protruding opening and the operating knob. Note that the cleaning solution that enters the case evaporates due to its volatility, but since the cleaning solution contains "dust" washed off from the board, the fine "dust" that entered the case with the cleaning solution remains as is. It will remain in the case,
If this "dust" remains attached to the contact electrode or the contact, it causes poor contact between the contact electrode and the contact. This problem becomes more serious as the cleaning liquid becomes dirty due to repeated cleaning.

For this reason, in the past, the parts except the push switch were attached to the board, the board was cleaned, and then the push switch was attached to the board, but this resulted in the process of attaching the parts to the board being duplicated. It has not been possible to streamline the assembly of electronic components by attaching components to the board all at once. Note that if you cover the protruding part of the push switch's knob with adhesive tape to prevent cleaning liquid from entering the case, you can clean the board with the push switch attached to the board. If you cover the area with adhesive tape, it becomes troublesome to apply the adhesive tape and peel it off after cleaning, which makes the assembly work of electronic devices inefficient. This method is said to be impractical because it is difficult to completely close the gap between the protruding opening and the operating knob, and therefore it is impossible to completely prevent the cleaning liquid from entering the case.

[Means to solve problems]

This invention is aimed at solving the above problem, and the return position of the movable body provided with the contact in the case of the push switch is set at a predetermined distance from the inner surface of the upper surface of the case. a return position regulating part for regulating the return position, and a moving body latching part for latching the moving body and locking the moving body at this position when the moving body is pulled up above the return position; When the movable body is returned to the return position by a return spring, the movable body is received from above by the return position regulating portion to stop the movable body at the return position, and the movable body is operated to stop the movable body at the return position. An engaging portion is provided that crosses over the return position regulating portion and engages with the movable body latching portion when the knob is forcibly pulled up by pulling the knob. To,
When the movable body is pulled up above the return position and its engaging portion is engaged with the movable body latching portion, the upper surface of the case is pinched between the inner surface of the upper surface of the case and the upper surface of the movable body. By providing a frame-shaped elastic packing material that seals watertightly around the knob protruding opening provided in the push switch itself, the push switch itself has a function to prevent cleaning liquid from entering, making it possible to clean the board while the push switch is attached to the board. It is designed to allow you to do this.

[Effect]

In other words, this invention removes the frame-shaped elastic packing material provided on the inner surface of the upper surface of the case or the upper surface of the movable body by forcefully pulling the operating knob of the movable body and forcibly lifting it above the return position. This elastic packing material is sandwiched between the inner surface of the upper surface of the case and the upper surface of the movable body to seal the area around the knob protruding opening in a watertight state, and this state is maintained between the engaging portion provided on the movable body and the inside of the case. According to this invention, the cleaning liquid enters the gap between the knob protrusion opening and the operation knob, and the liquid pressure is applied to the moving body. Even if the movable body acts on the top surface, the elastic packing material is held between the inner surface of the top surface of the case and the movable body is held by the engagement between the engaging portion and the movable body latching portion in the case. Because of this, the moving body is not pushed down by hydraulic pressure and the cleaning liquid does not enter the case, so it is possible to completely prevent cleaning liquid from entering the push switch.
Therefore, the board can be cleaned with the push switch attached to the board. Moreover, with this invention, by strongly pressing down on the operating knob, the engaging part of the movable body can be disengaged from the movable body latching part in the case, and the movable body can be pushed down to the lower side of its return position. Therefore, after cleaning, the movable body can be moved up and down under its return position, and in this state,
Since the movable body returned by the return spring has its engaging portion received by the return position regulating portion within the case, the movable body will not be moved above the return position by the spring force of the return spring. , the push switch can operate normally.

〔Example〕

An embodiment of this invention will be described below with reference to the drawings.

In FIGS. 1 to 7, 1 is a case of a push switch. This case 1 consists of a lower case 1a made of synthetic resin with an open upper surface, and an upper case 1b that covers the upper surface of the lower case 1a.
It is fixed to the lower case 1a by fitting into the outer periphery of the upper end of the lower case 1a and hooking pieces 2 formed on both sides of the upper case 1b into latching protrusions 3 provided on both outer surfaces of the lower case 1a. Further, numerals 4 and 4 indicate three terminals each on the left and right sides provided on both sides of the lower case 1a. These terminals 4, 4 were provided when the lower case 1a was molded, and the portions of the terminals 4, 4 that protrude outside the case 1 are used as external circuit connection parts, and the lower case 1a
The inner portions are contact electrodes 4a, 4a. The contact electrodes 4a, 4a are embedded in both inner surfaces of the lower case 1a so that the inner surface of the case is flush with the inner surface of the lower case 1a, and each of the terminal electrodes 4a, 4a is They are arranged as shown in FIG.

On the other hand, 6 is a synthetic resin movable body provided in the case 1 so as to be movable up and down, and this movable body 6
An operating knob 6a is integrally provided at the center of the upper surface of the upper case 1b and projects onto the case 1 from a knob protruding opening 5 provided at the center of the upper surface of the upper case 1b. The movable body 6 is guided and pushed down by the inner surface of the lower case by pushing the operation knob 6a, and is returned upward by a return spring 7 provided inside the lower case 1a when the pressing force is released. Contacts 8, 8 are provided on both sides of the movable body 6 to selectively short-circuit the respective contact electrodes 4a, 4a as the movable body 6 moves up and down. The contactor 8 is made of a leaf spring, and a movable body mounting hole provided at its base is fitted into a contactor mounting pin 9 protruding from the side surface of the movable body 6.
The tips of the contacts 8, 8 are slidably and resiliently contacted to the inner surface of the lower case on which the contact electrodes 4a, 4a are arranged.

The movable body 6 is set at a return position at a predetermined distance (about several mm) from the inner surface of the upper surface of the upper case 1b, and is pushed down from this return position by a push operation of the operating knob 6a. The movable body 6 is returned to the return position by the spring 7, and the return position of the movable body 6 is regulated as follows.

That is, in FIGS. 1 and 4, 1
0 and 10 are movable body stoppers provided in the upper part of the case 1 corresponding to the four corners of the movable body 6;
The stoppers 10, 10 are integrally formed on the inner surface of the lower case 1a. This stopper 10,1
0 has a triangular convex portion 11 whose upper and lower surfaces are inclined, protruding from the surface facing the movable body 6. The lower surface of this convex portion 11 allows the movable body 6 to return to the above position (upper case Return position regulating portion 11 that regulates the return position to a position that is a predetermined distance from the inner surface of the upper surface portion of 1b.
a, and the upper surface of this convex portion 11 is
When the movable body 6 is pulled up above its return position, the movable body 6 is hooked and the movable body 6 is locked at this position. On the other hand, each of the stoppers 11,
Elastic engagement pieces 12, 12 corresponding to the elastic engagement pieces 11 are integrally provided downwardly, and the movable body 6 is fixed to the return position by a return spring 7 on the side surface of each elastic engagement piece 12, 12. When the movable body 6 is returned to the above position, it is received from above by the return position regulating portion 11a and the movable body 6 is stopped at the return position, and when the movable body 6 is forcibly pulled up by strongly pulling its operation knob 6a. Triangular engagement convex portions 12a are provided to protrude, respectively, so that the elastic engagement pieces 12 are elastically deformed to overcome the return position regulating portion 11a and engage with the movable body latching portion 11b. In addition, this elastic engagement piece 1
2 is designed so that it will not be elastically deformed by the pressing force against the return position regulating portion 11a due to the spring force of the return spring 7. Therefore, the movable body 6 will not be elastically deformed by the pressing force applied to the return position regulating portion 11a by the spring force of the return spring 7. is the return position regulating part 1
Although the return spring 7 returns to the return position where the return position contacts 1a, any further rise is regulated by the return position regulating portion 11a.

Further, in FIGS. 1 and 3, reference numeral 13 denotes an elastic packing material provided on the inner surface of the upper surface of the upper case 1b. This packing material 13 is a frame-shaped material having an opening through which the operating knob 6a of the movable body 6 passes through the center of a watertight elastic plate (for example, a rubber plate) having approximately the same area as the inner surface of the upper surface of the upper case 1b. This packing material 13 has its outer periphery connected to the lower case 1a.
The lower case 1a and the upper case 1 are held in a compressed state between the upper end surface and the inner surface of the upper surface of the upper case 1b.
The joint part with b is sealed watertight. The movable body 6 has an engagement convex portion 12a of the elastic engagement piece 12 that is connected to the return position regulating portion 1.
1a, the movable body 6 is separated from the elastic packing material 13 as shown in FIG. When the movable body 6 is pulled up above the return position, the upper surface of the movable body 6 comes into contact with the elastic packing material 13 as shown in FIG. and the upper surface of the moving body in a compressed state. In other words, when the movable body 6 is pulled up above its return position, the elastic packing material 13 is held between the inner surface of the upper surface of the upper case 1b and the upper surface of the movable body, and is attached to the knob provided on the upper case 1b. The area around the protruding opening 5 is sealed watertight (sealed between the inner surface of the top surface of the upper case and the top surface of the moving body). When the top surface of the moving body 6 is pressed against the elastic packing material 13, this elastic packing material Case 1 by 13
The inside is completely sealed. Also,
The engaging protrusion 12a of the elastic engaging piece 12 provided on the moving body 6 forcibly pulls up the moving body 6 above the return position as described above and presses its upper surface into contact with the elastic packing material 13. When the movable body 6 is pulled upward, the movable body 6 crosses over the return position regulating portion 11a and engages with the movable body latching portion 11b. An elastic packing material 13 is sandwiched between the inner surface and the knob protruding opening 5 with this elastic packing material 13.
It is designed to maintain a watertight seal around the area.

In this way, the elastic packing material 13 is provided on the inner surface of the upper surface of the upper case 1b, and the upper surface of the moving body 6 can be brought into contact with the elastic packing material 13 by pulling the moving body 6 above its return position. This is so that the circuit board can be cleaned with the push switch attached to the circuit board of the electronic device.As mentioned above, the operating knob 6a is strongly pulled to forcibly pull up the moving body 6. If cleaning is performed with the movable body 6 locked by the movable body locking portion 11b with the top surface of the movable body 6 pressed into contact with the elastic packing material 13, the cleaning liquid will be applied to the knob protruding opening 5 on the top surface of the case. Since the cleaning liquid will not enter the case 1 through the gap with the knob 6a, even if the circuit board is cleaned with the push switch attached to the circuit board, the cleaning liquid will not enter the case 1 and the "dust" contained in this cleaning liquid will be removed. It adheres to the contact electrodes 4a, 4a and the contactor 8, and the contact electrode 4
There is no need to worry about poor contact between a, 4a and the contact 8. Also, after cleaning this board, all you have to do is forcefully press the operation knob 6a to forcefully push down the movable body 6.
If you forcibly push down the engaging convex portion 12a of the elastic engaging piece 12 provided on the moving body 6, the engaging convex portion 12a of the elastic engaging piece 12 will elastically deform and hold the moving body locking portion 11b on the case 1 side. Since the movable body 6 is unlocked by climbing over the movable body 6, the movable body 6 can be pushed down below its return position, and the movable body 6 can be returned to a vertically moving state below its return position.

On the other hand, in FIGS. 4 and 5, 14 is a cam plate that holds the movable body 6 at the switch switching position, and this cam plate 14 is located on the side surface perpendicular to the contact electrode arrangement surface in the lower case 1a. It is installed so that it can be moved laterally. The cam plate 14 is slidably supported with its lower surface on the inner bottom surface of the lower case 1a, and is provided vertically between the inner surface of the lower case 1a and the side surface of the movable body 6. , lower case 1
a and the moving body 6 to move laterally. An endless cam groove 15 having a shape as shown in FIG. 7 is formed on the surface of the cam plate 14 facing the movable body 6. The tip of the movable body lock pin 16 is inserted. This lock pin 16 is movably held in a horizontal hole 17 provided in the movable body 6, and a coil spring 18 for pressing the lock pin provided in the horizontal hole 17 keeps the tip of the pin in the cam groove of the cam plate 14. It is pressed into contact with the bottom surface. This lock pin 16 moves up and down together with the movable body 6 and moves within the cam groove 15 of the cam plate 14, and as the lock pin 16 moves up and down, the cam plate 14 is pushed against the side surface of the cam groove 15 by the lock pin 16. It's starting to move laterally. In addition, the cam groove 15 formed on this cam plate 14
The bottom surface of the cam groove 15 has a step as shown in FIG. It's summery.

The lock pin 16 is constantly pressed against the bottom surface of the cam groove by the lock pin pressing coil spring 18, and moves inside the cam groove 15 from part A to
The movable body 6 moves in the order of B part → C part and moves to D part, and is pushed down to the lowest lower limit position.As the pushing force is released, the moving body 6 is pushed up by the spring force of the return spring 7, and from D part. The movable body 6 moves to part E, is received by the lock pin engaging part a, and is pushed down to the push-down position shown by the chain line in FIG. The switch is locked at a switching position in which the electrode 4a and the contact electrode 4a on the lower right side are short-circuited. In addition, the lock is released by pushing down the movable body 6 again at this push-down position. When the movable body 6 is pushed down, the lock pin 16 separates from the lock pin retaining portion a and moves into the cam groove 15. When the moving body 6 is pushed up by the spring force of the return spring 7, the lock pin 16 moves inside the cam groove 15 from the F part to the G part to the H part. The movable body 6 sequentially moves back to the A section and returns to the return position where the engaging convex portion 12a is received by the return position regulating portion 11a (the contact electrode 4a on the left side and the contact electrode on the upper right side shown in Fig. 6). 4a are short-circuited by the contactor 8). The upper end (portion A) of the cam groove 15 extends further upward from the position of the lock pin 16 when the movable body 6 is returned to the return position. The lock pin 16 is inserted into this extended portion when the knob is pulled up to seal around the knob protruding opening 5.

However, in this push switch,
By strongly pulling the operation knob 6a of the movable body 6 as described above and forcibly lifting it above the return position, the frame-shaped elastic packing material 13 provided on the inner surface of the upper surface of the upper case 1b is attached to the upper case. The elastic packing material 13 is held between the inner surface of the upper surface of the upper case 1b and the upper surface of the moving body 6, and the area around the knob protruding opening 5 provided on the upper surface of the upper case 1b is sealed watertightly. Since the state is maintained by the engagement between the elastic engagement piece 12 provided on the moving body 6 and the moving body latching portion 11b provided in the case 1, this push switch can be attached to the board of the electronic device. Even if the board is cleaned in the same state, the cleaning liquid will not get into the push switch. In other words, according to this push switch, when cleaning the board with the push switch attached to the board, the cleaning liquid enters the gap between the knob protruding opening 5 and the operating knob 6a, and the liquid pressure acts on the top surface of the movable body 6. However, the movable body 6 is in a state where the elastic packing material 13 is held between the inner surface of the upper surface of the case 1 by the engagement of the elastic engagement piece 12 with the movable body retaining portion 11b inside the case 1. Because it is held, the moving body 6 is not pushed down by hydraulic pressure and the cleaning liquid does not enter the case 1. Therefore, it is possible to completely prevent the cleaning liquid from entering the push switch. , the board can be cleaned with the push switch attached to the board. In addition, in the case of an ultra-small push switch,
Because its height, that is, the distance from the terminal on the bottom surface to the top surface of the switch, is very small, when the terminal of this push switch is soldered to the terminal electrode on the board, flux enters the switch through the opening where the knob protrudes from the top surface of the case. Although this may be a concern, according to the push switch described above, the terminals 4, 4 of the push switch can be soldered to the terminal electrodes on the board while the movable body is pulled up and the area around the knob protruding opening 5 is sealed. , 4 can also be prevented from entering the switch during soldering. Moreover, in this push switch, by strongly pressing down the operating knob 6a, the elastic engagement piece 12 of the movable body 6 is disengaged from the movable body latching portion 11b in the case 1, and the movable body 6 is moved below its return position. Since the movable body 6 can be pushed down to the side, the movable body 6 can be moved up and down below its return position after cleaning, and in this state, the movable body 6 returned by the return spring 7 can be Since the elastic engagement piece 12 is received by the return position regulating portion 11a inside the case 1, the movable body 6 will not be moved above the return position by the spring force of the return spring 7, so that the push switch can be operated normally. can be operated.

In the above embodiment, the engaging portion provided on the movable body 6 side and received by the return position regulating portion 11a and the movable body latching portion 11b in the case 1 is the elastic engaging piece 12, but this is not the same. Conversely, the stopper 10 on the side of the case 1 in which the return position regulating part 11a and the movable body latching part 11b are formed may be a stopper piece that deforms elastically. Latch part and moving body 6
Of course, the engaging portions on the sides can also be arbitrarily selected without being limited to the above embodiments, such as having one side as a recess and the other as a convex portion. Further, in the above embodiment, the lower case 1 is
Although the joint between a and upper case 1b is also sealed,
The joint between the lower case 1a and the upper case 1b may be sealed using another packing material.
In that case, the elastic packing material 13 is
It may be provided on the top surface.

[Effect of idea]

This idea allows the frame-shaped elastic packing material provided on the inner surface of the top surface of the case or the top surface of the movable body to be removed from the case by forcefully pulling the operating knob of the movable body and forcibly lifting it above the return position. This elastic packing material is sandwiched between the inner surface of the upper surface portion and the upper surface of the movable body to seal the circumference of the knob protruding opening in a watertight state, and this state is maintained between the engaging portion provided on the movable body and the inside of the case. According to this invention, when the push switch is attached to the circuit board of an electronic device and the circuit board is cleaned, the cleaning liquid does not stick out when the push switch is attached to the circuit board of the electronic device. Even if the hydraulic pressure enters the gap between the opening and the operating knob and acts on the top surface of the moving body, the moving body will be held in place by the elastic packing material due to the engagement between the engaging part and the moving body latching part in the case. Because it is held between the inner surface of the upper surface of the case and the moving body is not pushed down by hydraulic pressure and the cleaning liquid enters the case, the cleaning liquid does not enter the push switch. Since it is possible to completely prevent the intrusion of foreign substances, the board can be cleaned with the push switch attached to the board. Moreover, with this invention, by strongly pressing down on the operating knob, the engaging part of the movable body can be disengaged from the movable body latching part in the case, and the movable body can be pushed down to the lower side of its return position. Therefore, after cleaning, the movable body can be moved up and down below its return position, and in this state, the movable body that is returned by the return spring moves its engaging part to the position regulating the return position within the case. Since the movable body is not moved above the return position by the spring force of the return spring, the push switch can be operated normally.

[Brief explanation of the drawing]

The drawings show one embodiment of this invention, and FIG. 1 is a longitudinal sectional front view of the push switch with the moving body in the return position and with the moving body pulled up above the return position, FIGS. Figure 3 is a front view and partially cutaway plan view of the push switch;
5 and 5 are a cross-sectional plan view and a longitudinal sectional side view of the push switch, FIGS. 6 and 7 are cross-sectional views taken along the - line in FIG. 1 and the - line in FIG. 5, and FIG. 8 is a cam plate formed FIG. 3 is a developed sectional view of a cam groove. 1...Case, 1a...Lower case, 1b...Upper case, 4...Terminal, 4a...Contact electrode, 5...
Knob protruding opening, 6... Moving body, 6a... Operation knob, 7... Return spring, 8 contact, 10... Moving body stopper, 11... Convex portion, 11a... Return position regulating portion, 11b... Moving body latching portion, 12... elastic engagement piece, 12a... engagement convex portion, 13... elastic packing material.

Claims (1)

[Scope of utility model registration request] A case with multiple contact electrodes arranged on the inner surface,
A movable body that is provided in the case so as to be movable up and down, and that is pushed down by the push operation of an operating knob that protrudes above the case from a knob protruding opening provided on the upper surface of the case, and is returned upward by a return spring provided in the case. and a contactor provided on the movable body to selectively short-circuit the plurality of contact electrodes by vertical movement of the movable body. a return position regulating part that regulates the movable body to a position at a predetermined distance with respect to the inner surface of the part; A movable body locking portion is provided on the movable body, and when the movable body is returned to the return position by the return spring, the movable body is received from above by the return position regulating portion and the movable body is An engaging portion is provided that is stopped at a return position and that, when the operating knob is strongly pulled and the movable body is forcibly pulled up, the movable body overcomes the return position regulating portion and engages with the movable body latching portion; The inner surface of the upper surface of the case or the upper surface of the movable body, when the movable body is pulled up above the return position and its engaging portion is engaged with the movable body latching portion, the inner surface of the upper surface of the case. A push switch characterized in that a frame-shaped elastic packing material is provided which is held between the upper surface of the movable body and seals the periphery of the knob protruding opening in a watertight state.