JPS6033542Y2 - keyboard switch - Google Patents

Description

[Detailed description of the invention] This invention relates to an alternate type keyboard switch that is applied to the input section of a computer, etc.
More specifically, even if an overload such as a strong impact is applied to the inside of the switch due to the push button of the switch, the proper function of the switch can always be maintained.

Alternate keyboard switches like the example above are
Normally, when the push button is pressed the first time, it retracts and locks in place, and when the push button is pressed the second time, the lock is released and protrudes to the original position.This push button is printed. A keyboard is configured by arranging a plurality of them on a board.

In addition, this type of switch uses an alternate mechanism to freely lock and release the push button, but this alternate mechanism operates properly by forcefully engaging the upper end of the arm pin with the heart cam. .

However, since the engaging portion at the upper end of the arm pin is biased and engaged by the elasticity of the arm pin itself, there is a risk that the engaging portion of the arm pin may come off and return to its original position when a large shock or vibration is applied. .

This is because a protective gap is provided in the arm pin housing part of the case to prevent the arm pin from hitting the case and causing damage or trouble during assembly, and to prevent the arm pin from impairing the biasing engagement movement. This is because the arm pin vibrates and comes off in this protective gap.

For this reason, it has the disadvantage that it is unsuitable as a general operation switch that is susceptible to relatively large shocks from people other than the operator.

Therefore, the object of this invention is to provide a keyboard switch whose arm pin will not come off even if a large impact is applied to the push button.

According to this invention, a metal plate is disposed at the rear of the arm pin, so even if an overload due to the push button is transmitted to the inside of the switch, the arm pin is held and guided by the rear metal plate. Due to the elasticity of the arm pin itself, the arm pin operates smoothly without vibrating or bouncing inside the switch, preventing it from coming off the heart cam, allowing a proper alternate mechanism to be maintained at all times, and with excellent shock and vibration resistance. It can be effective.

An embodiment of this invention having such characteristics will be described in detail below based on the drawings.

The drawing shows a keyboard switch equipped with an alternate mechanism when used in the input section of a general switch such as a jukebox, and as shown in FIGS. 1 and 2, 1 is a case of the keyboard switch, An operating shaft 3 integrated with a push button 2 is vertically inserted through the upper surface of the case 1 so as to be able to slide vertically, and a switch circuit 4 is provided on the lower surface of the case 1.
The arm pin 5, a metal plate 6 for holding the arm pin, and a base 8 for supporting the terminal 1 are fitted and fixed to form a keyboard switch.

The aforementioned operation shaft 3 has a heart cam 9 formed on its side surface, and the upper end engaging portion of the arm pin 5 engages with the heart cam 9 to form an alternate mechanism to be described later.

Further, a magnet piece 10 is attached to the side surface opposite to the heart cam 9, and sliding protrusions 12°12 are formed on both side surfaces perpendicular to these sides to be engaged with the guide groove 11 of the case 1. The operating shaft 3 is always urged outward from the case 1 by a coil spring 13 provided between the operating shaft 3 and the base 3.

The above-mentioned switch circuit 4 is installed on the base 8 on the side opposite to the magnet piece 10, has a magnetically sensitive element such as a Hall element or a reed switch, and changes the distance between the magnet piece 10 and the magnet piece 10 based on the pressing operation of the push button 2. This switch circuit 4 is activated by the action.

17 is a terminal of the switch circuit.

The terminal 7 is formed in a T-shape, and its vertical piece penetrates the base 8 as an external terminal, and its horizontal pieces have fitting protrusions 14 and 1 formed on the upper surface of the base 8 at the center and both ends thereof, respectively.
5 and 16 and fixed with adhesive. Sometimes, this terminal installation is done by placing the U-shaped bent portion of the lower end of the arm pin 5 between the fitting protrusions 14 and 16 on both ends of the base 8. The lower end of the arm pin 5 is sandwiched between the horizontal piece of the terminal 7 and the upper surface of the base 8.

That is, the arm pin 5 is supported by the base 8 at the same time that the inner end of the terminal 7 is fixed to the base 8.

The above-mentioned metal plate 6 is arranged in a so-called upper and lower sandwiched state in which the upper end is in contact with the inner surface of the case and the lower end is in contact with the upper surface of the terminal 7 in the gap of the case formed at the rear position of the arm pin 5. The metal plate 6 serves to suppress unnecessary movement of the arm pin 5, and also to absorb conductive heat generated using the terminal 7 as a medium when the printed circuit board is mounted because the lower surface of the metal plate 6 is in close contact with the upper surface of the terminal 7. be.

For this reason, the metal plate 6 is made of a metal such as copper that has good thermal conductivity.

Further, at this time, the terminals 7 are in a state of being pressed down by the metal plate 6, and can also serve as a member to prevent the terminals 7 from coming off when the printed circuit board is attached.

Further, this metal plate 6 is disposed with an appropriate gap from the arm pin 5 so that the upper end engaging portion of the arm pin 5 does not interfere with the ups and downs when it goes around the heart cam 9.

It goes without saying that even when the rear surface of the arm pin 5 is in contact with the metal plate 6 and is supported and guided, it is always engaged with the heart cam 9.

The above-mentioned alternate mechanism is constructed by the upper end of the arm pin 5 attached to the base 8 engaging with the recess of the heart cam 9, which has a bar-shaped projection and a recess provided so as to go around the projection. A double-press configuration of the switch is formed based on this alternate mechanism.

In the keyboard switch configured in this way, when the customer presses the push button 2 for the first time, the operation shaft 3 integrated with the push button 2 is moved by the coil spring 1.
3, it sinks into the case 1 while being supported and guided by a pair of left and right sliding protrusions 12, 12.

At this time, the end engaging portion of the arm pin 5 goes around the heart cam 9 and is locked in the central recess of the heart cam 9, and the operating shaft 3 remains recessed into the case 1.

At this time, the magnet piece 10 provided on the operating shaft 3 and the switch circuit 4 face each other, and the switch circuit 4 is operated based on the magnetic action, thereby performing input processing to the switch.

By the way, when a strong pressing blade such as an impact acts on the push button 2, the arm pin 5 tries to vibrate due to its elasticity, but since it is guided and protected from behind by the metal plate 6, the vibration of the arm pin 5 is significantly suppressed. The movement is always smooth compared to heart cam 9.

Then, when the push button 2 is pressed a second time, the end engaging portion of the arm pin 5 is biased in the direction in which the locking force is released based on the sliding movement of the operating shaft 3, and the end engaging portion of the arm pin 5 is moved around the heart cam 9. and return to the original position.

As a result, the operating shaft 3 also returns to its original position protruding from the case 1, and is ready for the next press of the push button.

It is preferable that the metal plate be protected to the extent that it does not interfere with the movement of the arm pin, and in the above-described embodiments, both edges of the lower end of the metal plate are formed inward.

[Brief explanation of drawings]

The drawings show an embodiment of this invention, with FIG. 1 being a vertical sectional side view of a keyboard switch, and FIG. 2 being a perspective view showing the essential parts of the keyboard switch developed. 1...Case, 3...Operation axis, 5...
...Arm pin, 6...Metal plate, 7
...Terminal, Death...Base, 9...
・Heart cam.

Claims (1)

[Scope of Claim for Utility Model Registration] A keyboard switch in which a heart cam is formed on the side of an operating shaft that moves up and down with respect to the case, and an alternate mechanism is formed by engaging this heart cam with the upper end of an arm pin attached to the base. A keyboard switch configured such that a metal plate is inserted into a gap in a case formed behind the arm pin, the arm pin is held by a base and a terminal, and the upper surface of the terminal is pressed down by the metal plate.