JPS636827Y2 - - Google Patents

Description

[Detailed description of the invention] The present invention has an inner cylinder rotatably provided within the outer cylinder, a plate tumbler movable in a direction perpendicular to the axis of the inner cylinder, and a In the key lock mechanism of the key switch, the inner circumferential surface is provided with a locking groove and a relief groove, into which the plate tumbler enters, at axially symmetrical positions, respectively, so that the key can be inserted and removed only at a specified position of the inner cylinder relative to the outer cylinder. Regarding the idea.

Generally, the key lock mechanism of this type of key switch is constructed as shown in FIG. FIG. 1 is a cross-sectional view perpendicular to the axis of the inner cylinder, and shows the circular hole 2 of the outer cylinder 1.
An inner cylinder 3 is inserted into the outer cylinder 1, and the inner cylinder 3 is rotatably provided within the hole 2 of the outer cylinder 1. The inner cylinder 3 is provided with a plate tumbler hole 4 having a rectangular cross section and penetrating in the vertical direction.
A plate tumbler 5 with approximately equal length is placed in the hole 4.
is stored so that it can be moved up and down. Although not shown, a plurality of plate tumbler holes 4 are sequentially provided in the axial direction of the inner cylinder 3, and a plate tumbler 5 is accommodated in each hole 4, respectively. The plate tumbler 5 has a coil spring 6
is constantly biased in the circumferential direction by
One end portion 5a thereof enters into a locking groove 7 provided on the inner circumferential surface of the outer cylinder 1 (see FIG. 1). This state is a locked state, and at this time the inner cylinder 3 cannot rotate within the outer cylinder 1. And to unlock this, inner cylinder 3
A key (not shown) is inserted into a key hole 8 provided through the plate tumbler 5 in the axial direction of the inner cylinder, and the plate tumbler 5 is pushed upward against the elasticity of the coil spring 6 using the key thread provided with the key. The inner cylinder 3 can freely rotate within the outer cylinder 1 by moving the one end 5a out of the locking groove 7 and making the plate tumbler 5 so that neither the upper nor lower surface of the inner cylinder 3 protrudes. By the way, this keyhole 8
When the key is inserted or removed, the plate tumbler 5 moves up and down in the hole 4 along the peaks and troughs of the key ridge, but at this time, the other end 5b of the plate tumbler 5 protrudes and retracts from the upper surface of the inner cylinder 3. For this reason, an escape groove 9 for allowing this protrusion and retraction is provided at the upper part of the inner circumferential surface of the outer cylinder 1, that is, at a position axially symmetrical to the locking groove 7. Conventionally, in the key lock mechanism configured as described above, both ends 5a and 5b of the plate tumbler 5 have the same widths a and b, so that they cannot enter into either the locking groove 7 or the relief groove 9. This allows the plate tumbler 5 to move up and down even when the inner cylinder 3 is rotated 180 degrees within the hole 2 of the outer cylinder 1, making it possible to insert and remove the key. I had the inconvenience of being able to do it. In order to eliminate this inconvenience, conventionally, as shown in FIG. There is one in which the groove 7 is a non-groove portion 10. In this case, if you try to remove the key with the inner cylinder 3 rotated 180 degrees within the hole 2 of the outer cylinder 1, the non-grooved part 1
The other end 5b of the plate tumbler 5 in the 0 part collides with the non-groove part 10 of the locking groove 7, preventing the plate tumbler 5 from moving, so the key cannot be removed. It is necessary to secure at least one extra plate tumbler 5 as a special part to prevent the tumbler from coming off, which increases the number of parts and assembly man-hours.
This also resulted in the inconvenience of increasing the size of the product.

The present invention has been developed in view of the above points, and is a key switch that has a simple structure and allows the key to be inserted and removed only at the specified position of the inner cylinder relative to the outer cylinder, without requiring special parts to prevent the key from coming out. The purpose is to provide a key lock mechanism. In order to achieve this object, the present invention provides an inner cylinder rotatably provided within the outer cylinder, a plate tumbler movably provided within the inner cylinder in a direction orthogonal to the axis of the inner cylinder, and a In a key lock mechanism of a key switch, a locking groove into which one end of the plate tumbler enters and a relief groove into which the other end enters are provided at axially symmetrical positions on the inner circumferential surface of the plate tumbler. The width c, the width d of the other end, the width C of the locking groove, and the width D of the relief groove are formed in the relationship c<C<d<D.

The following is an example of the present invention shown in Figures 3 to 5.
This will be explained in detail using figures. FIG. 3 shows an outline of the overall structure of the key switch, with a being a front view and b a partially sectional side view. FIG. 4 is a sectional view taken along the line -- in FIG. 3 and shows the key lock mechanism. A stepped cylindrical inner cylinder 13 is inserted into the stepped circular hole 12 of the outer cylinder 11 from the rear end opening side, and the inner cylinder 13 is inserted into the stepped portion 14 of the hole 12.
After making contact with the stepped portion 15 of the inner cylinder 13, the rotor 17 is fitted and connected to the rectangular cross-section protrusion 16 located at the center of the rear end surface of the inner cylinder 13, and the printed circuit board 18 is attached to the rear end surface of the outer cylinder 11 with screws. A cylinder 13 is rotatably provided within the hole 12 of the outer cylinder 11. The inner cylinder 13 is provided with plate tumbler holes 19 (two in this example) having a rectangular cross section and passing through the inner cylinder 13 in the vertical direction, and the plate tumblers 20 are housed in the holes 19 . The thickness and width of the plate tumbler 20 are slightly smaller than the plate tumbler hole 19, and the plate tumbler 20 can freely move in the vertical direction within the plate tumbler hole 19. Further, the length of the plate tumbler 20 in the vertical direction is approximately equal to the length of the plate tumbler hole 19 in the vertical direction. The plate tumbler 20 has a spring receiver 21, and the spring receiver 21 is connected to a bottomed coil spring hole 22 which is provided in communication with the side of the plate tumbler hole 19.
It protrudes inward and is biased in the circumferential direction of the inner cylinder by the elastic force of a coil spring 23 housed in this hole 22. Therefore, the plate tumbler 20 is pressed against the outer cylinder 11 by a force applied in the direction of the elastic force of the coil spring 23, and one end 20a of the plate tumbler 20 is pressed against the outer cylinder 11.
The hole 12 enters into a locking groove 24 provided at the lower part of the inner circumferential surface of the hole 12 (see FIG. 4). This state is a locked state, and at this time rotation of the inner cylinder 13 is prevented.
To unlock this, a key (not shown) is inserted into the key hole 25 provided through the outer cylinder 11, the inner cylinder 13, and the plate tumbler 20, and the coil spring 23 is unlocked by the key thread provided on the key. The plate tumbler 20 is moved upward against the elastic force to remove its one end 20a from the locking groove 24, and the plate tumbler 20 is inserted into the inner cylinder 1.
3, the inner cylinder 13 becomes rotatable within the hole 12 of the outer cylinder 11.
Furthermore, when the key is inserted into or removed from the keyhole 22, the plate tumbler 20 moves vertically along the peaks and troughs of the key ridge, and as a result, the other end 20b of the plate tumbler 20
protrudes and retracts from the upper surface of the inner cylinder 13, so an escape groove 26 for allowing this protrusion and retraction is provided at the upper part of the inner peripheral surface of the hole 12 of the outer cylinder 11, that is, at a position symmetrical to the locking groove 24 with respect to the central axis of the hole 12. be. The key lock mechanism constructed as described above is similar to that of the prior art. As shown in FIG. 4, the key lock mechanism according to the present invention is formed so that the width c of one end 20a of the plate tumbler 20 in the urging direction is smaller than the width d of the other end 20b, that is, c<d. , the width C of the locking groove 24 and the width D of the relief groove 26 are respectively determined at both ends 20a and 20b of the plate tumbler 20.
is slightly larger than the width c, d of, i.e., c<C
It is formed to satisfy the relationship <d<D. By forming the locking groove 24 and relief groove 26 at both ends of the plate tumbler 20 in this way, the fourth
Insert the key into the keyhole 25 from the locked state shown in the figure, move the plate tumbler 20 upwards, move its one end 20a out of the locking groove 24, and unlock the inner cylinder 13 by 180 degrees as shown in Fig. 5. When attempting to remove the key in the rotated position, the width d of the other end 20b of the plate tumbler 20 is larger than the width C of the locking groove 24, so the other end 20b cannot enter into the locking groove 24 and the key is removed. Since the other end 20b of the plate tumbler 20 is prevented from protruding and retracting from the circumferential surface of the inner cylinder 13, which is necessary when inserting and removing the key, the key cannot be removed. Therefore, the inner cylinder 13
The key cannot be inserted or removed at any position other than the specified position with respect to the outer cylinder 11, and the key can be inserted or removed only at the specified position.

Although not shown in the drawings, the key switch in this embodiment has internal teeth on the inner circumferential surface 27 of the outer cylinder 11, and is an elastic type having protrusions that elastically engage between the teeth. An arm is provided along the rear outer peripheral surface 28 of the inner cylinder 13, and a moderation mechanism is provided to temporarily stop the rotation of the inner cylinder 13 according to a predetermined moderation. Also rotor 17
There is a movable contactor 29 which comes into contact with and separates from a plurality of fixed contacts (not shown) provided on the printed circuit board 18 as the inner cylinder 13 rotates, thereby forming a plurality of switches. A plurality of switches are provided, one each corresponding to a position where the rotation of the inner cylinder 13 is temporarily stopped. Furthermore, a plurality of (five in this example) rotation limiting grooves 31 having different lengths along the circumferential direction are sequentially provided in the axial direction on the front inner circumferential surface 30 of the outer cylinder 11, with the key insertion/extraction position as a reference point. By appropriately selecting the position of the key thread of the key that enters the rotation restriction groove 31, the rotation of the inner cylinder 13 can be restricted to a predetermined rotation angle.

The key lock mechanism of the key switch of the present invention is constructed as described above, but does not require any special parts to prevent the key from being removed, and has a width c at one end of the plate tumbler and a width d at the other end. , the width C of the locking groove and the width D of the relief groove are formed in the relationship c<C<d<D, respectively, making it possible to insert or remove the key at a position other than the specified position of the inner cylinder relative to the outer cylinder. Since the key can be inserted and removed only at the specified position, it is extremely economical and has the advantage that the product can be made smaller.

[Brief explanation of the drawing]

Figures 1 and 2 are cross-sectional views perpendicular to the inner cylinder axis showing the key lock mechanism of a conventional key switch, and Figure 3 shows an embodiment of the present invention, showing an outline of the overall structure of the key switch, and a is a front view. Fig. 4 shows the key lock mechanism of the present invention, and Fig. 5 is a cross-sectional view taken along the - line in Fig. 3. Fig. 5 is a cross-sectional view of the inner cylinder rotated 180 degrees from the state shown in Fig. 4. It is a diagram. DESCRIPTION OF SYMBOLS 11... Outer cylinder, 13... Inner cylinder, 20... Plate tumbler, 20a... One end, 20b... Other end, 2
3...Coil spring, 24...Lock groove, 26...Escape groove.

Claims (1)

[Scope of utility model registration request] An inner cylinder is rotatably provided within the outer cylinder, a plate tumbler is provided within the inner cylinder so as to be movable in a direction orthogonal to the axis of the inner cylinder, and a plate tumbler is provided on the inner circumferential surface of the outer cylinder at an axially symmetrical position. In the key lock mechanism of the key switch, which is provided with a locking groove into which one end of the plate tumbler enters and a relief groove into which the other end enters, the width c of the one end 20a of the plate tumbler 20, and the width of the other end 20b. d, the width C of the locking groove 24, and the width D of the relief groove 26, each of which is formed to have a relationship of c<C<d<D.