JPH0532916Y2 - - Google Patents

Description

[Detailed Description of the Invention] <Technical Field> This invention relates to a key switch that is assembled into an electronic device such as a computer.

<Prior art and its disadvantages> Generally, this type of switch has a cylinder lock 10 into which a specific key 101 is inserted, as shown in FIG.
2, and a micro switch 105 attached to the rear end bracket portion 104 of the main body 103 of the cylinder lock 102. When the key 101 is rotated, the cam 107 is rotationally displaced by the rotor 106 in the main body 103, and the rod 108 pivots rearward (to the right). When the micro switch 105 is pressed, the micro switch 105 is turned on.

However, in the structure described above, the structure of the rod portion on the cylinder lock 102 side, such as the rod guide portion 110, is relatively complicated.
Since the suitable pushing stroke of the actuating pin 109 by the actuator 8 is generally extremely short, about 1.0 to 1.5 mm, depending on the length of the rod due to the dimensional tolerance of the rod 108, etc., or the deviation of the operating point of the micro switch 105, etc. If there is, there is a problem that this may directly cause the microswitch 105 to malfunction, or the microswitch may be destroyed due to overstroke.

<Purpose of the invention> This invention was made in order to eliminate the drawbacks of the above-mentioned conventional ones, and its purpose is to provide a key switch that can simplify the structure and stabilize the switch operating characteristics.

<Structure and effects of the invention> In order to achieve the above object, this invention connects an operating cam that is biased axially backward by a spring to a cylindrical body fixed to a rotor so that the operating cam can move axially. The actuating pin of the micro switch is directly pushed in and driven.

In this invention with the above structure, the operation cam that is linked to the rotor can directly push and drive the operating pin of the microswitch, so the structure is simpler than the conventional rod-based one, and in particular, the spring force is applied to the operation cam. Therefore, even if there is a shift in the operating point of the micro switch, this can be absorbed by the elastic displacement of the operating cam. More specifically, the overstroke of the operating pin is absorbed by the spring. , can ensure accurate operation of the microswitch. In addition, since the spring has approximately the same spring pressing force whether or not the convex portion 17a of the operating cam 17 is pressing the operating pin 18, the operation of the actuator of the micro switch is stabilized and reliable. Improves sex.

<Example> An example of this invention will be described below with reference to the drawings.

FIG. 1 shows an example of a key switch according to this invention. In the figure, a rotor 6 having a key insertion hole 4 into which a specific key 3 is inserted, a tumbler 5 that engages with the key 3, etc. is rotatably arranged in a rotor case 2 that also serves as the main body of the cylinder lock 1. It is set up. A notch cam 7 fitted onto the rear end projection 6a of the rotor 6 and a steel ball 9 pressed against the cam surface of the notch cam 7 by a leaf spring 8 constitute a moderation mechanism 10 for the rotational displacement of the rotor 6.

A hollow bracket 1 is provided at the rear end of the main body 2.
1 is tied to this bracket 11,
A switch holder 13 of the micro switch 12 is fixed with a screw body 14. Above bracket 11
A bottomed cylindrical body 15 is fixed to the rear end protrusion 6a of the rotor 6 by a screw body 16 in the hollow portion. An operating cam 17 as shown in FIG. 2 is fitted into the cylindrical body 15 so as to be movable only in the axial direction.
A coil spring 19 for pressing the cam surface at the rear end against the operating pin 18 of the micro switch 12 is housed. The coil spring 19 is always in a compressed state. The operation cam 17 is prevented from coming off by fitting a protrusion 20 (FIG. 2) formed on its outer peripheral surface into a long hole 21 of the cylindrical body 15. In the above configuration, when the key 3 is inserted into the key insertion hole 4, the tumbler 5 engages with the key 3. In this state, when the key 3 is turned by a predetermined angle, for example, 1/4 turn, the rotor 6 rotates. Due to the rotation of the rotor 6, the cylindrical body 15 also rotates, thereby rotationally displacing the operating cam 17. Due to this rotational displacement of the operating cam 17,
Convex portions 17a, 17a forming the cam surface of the cam 17
(Figure 2) is the operating pin 1 of the micro switch 12.
8, 18, and press the operating pins 18, 18.
The micro switch is turned on to drive the motor. Conversely, when the key 3 is rotated in the return direction, the convex portions 17a, 17a of the operating cam 17 are disengaged from the operating pins 18, 18 of the micro switch 12, so that the micro switch 12 is turned off. In the above operation, since the coil spring 19 is always in a compressed state, the operation cam 17 does not move in the axial direction while the key 3 is being rotated. In other words, the micro switch is turned on and off by the rotation of the operating cam 17.

Here, the operation cam 17 interlocked with the rotor 6
When the convex portions 17a, 17a push the operating pins 18, 18 of the micro switch 12 due to rotational displacement, the coil spring 19 absorbs the overstroke of the operating pins 18, 18. In other words, if
Without the coil spring 19, the actuating pins 18, 18 would be pushed too far, leading to overstroke and damage to the micro switch.
This will absorb the overstroke. The overstroke is the distance that the actuating pin moves further in the axial direction than the proper stroke, which is just beyond the operating point of the microswitch until it hits the internal stopper. Therefore, if there is a shift in the operating point of the micro switch, the overstroke amount described above will change, but because of the coil spring 19, even if there is a change in the overstroke, that stroke amount will be completely absorbed. As a result, the stroke of the actuating pin is always a proper stroke. In other words, operation cam 1
7 is receiving the spring force of the coil spring 19, so
Even if there is a deviation in the operating point of the micro switch 12, it is corrected by the elastic displacement in the axial direction of the operating cam 17 that receives the spring force, so that the on/off operation of the micro switch 12 can be performed reliably. become. For the same reason, Rod 10 in Figure 3
Even if there is an error in the length of the operating cam 17, which is considered to correspond to 8, and the overstroke of the operating pin changes due to this, the overstroke of the operating pin is completely absorbed by the coil spring 19. Therefore, the on/off operation of the microswitch becomes reliable.

Further, the operating pins 18, 18 can be directly operated by the operating cam 17 which is interlocked with the rotor 6 without changing the direction of motion.
Since it is configured to be driven by pushing, the conventional rod guide part etc. can be omitted, simplifying the structure.

[Brief explanation of the drawing]

FIG. 1 is a sectional view showing an example of a key switch according to this invention, FIG. 2 is a perspective view showing the operating cam portion of FIG. 1, and FIG. 3 is a sectional view showing a conventional key switch. 1... Cylinder lock, 2... Body, 3... Key,
4...Key insertion hole, 12...Micro switch, 1
5... Cylindrical body, 17... Operation cam, 19... Spring member.

Claims (1)

[Scope of utility model registration request] A micro switch 12 attached to the rear end of the main body 2 of the cylinder lock 1 into which a specific key 3 is inserted;
A rotor 6 disposed inside the main body 2 and rotated by the key 3, a cylindrical body 15 fixed to the rear end of the rotor 6, and the cylindrical body 15 movable only in the axial direction. The operating cam 17 has a substantially cylindrical shape and has a convex portion 17a forming a cam surface at its rear end, and when the key 3 rotates by a predetermined angle, the convex portion The mounting position of the operating cam 17 to the cylindrical body 15 is determined such that the cam 17a faces the operating pin 18 of the micro switch 12, and the operating cam is interposed between the cylindrical body 15 and the operating cam 17. A spring member 1 that constantly applies a spring force to the micro switch side with respect to 17
9, the operation cam 17 rotates and the convex portion 1
7a presses the actuation pin 18, and the spring force of the spring member 19 when the operation cam 17 does not rotate and the protrusion 17a is not on the actuation pin 18. A key switch characterized in that the pressure is approximately the same.