JPS6222212B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a small rotary digital switch suitable for use by being attached to a printed circuit board. A rotary digital switch is formed with a concave part 13 and a convex part 14, and opens and closes the fixed terminal 8 by moving the movable contact 17 up and down in the axial direction using the concave part 13 and convex part 14. A plurality of grooves 22 are radially recessed in the lower surface of the case 1 that is placed on the cam block 10, and a convex portion 21 is provided protrudingly on the upper surface of the outer periphery of the spring seat 19, which is formed by bending a plate material into a substantially V-shaped cross section. This device is characterized in that a convex portion 21 of a spring seat 19 mounted on the upper part of the cam block 10 is engaged with a groove in the case 1.

Conventionally, in this type of digital switch,
It has a structure in which multiple contact pieces slide on the surface of a rotating plate such as a printed circuit board on which a conductive pattern is formed, and it is technically difficult to form fine patterns. Since it is necessary to properly arrange a plurality of contact pieces, the structure becomes complicated, expensive, and somewhat large, and it is difficult to make it into a dip size (terminal spacing of 2.54 mm).

The present invention solves the above-mentioned drawbacks, and embodiments will be described below with reference to the drawings.

In the figure, 1 is a box-shaped case made of synthetic resin, etc., and a hole 2 is provided in the center of the surface.
Numbers 3 such as 0, 1, 2, etc. are displayed around the , and fitting holes 4 are provided on the two corresponding sides. 5 is a base made of the same material as case 1,
A shaft 6 is formed in the center, and a common terminal 7 is provided on one side of two corresponding edges, and a plurality of fixed terminals 8 are provided on the other side. A fitting protrusion 9 is provided on the other corresponding edge in correspondence with the fitting hole 4 of the case 1.

Reference numeral 10 denotes a disc-shaped cam block made of synthetic resin, etc., and a shaft 1 having a groove 11 for operation in the center.
2, and a plurality of recesses 13 and projections 14 formed in the axial direction are provided on the surface of the circumferential portion, and the recesses 13 and projections 14 perform a cam action. Reference numeral 15 denotes a center hole provided at the center of the back surface of the cam block 10 corresponding to the shaft 6 of the base 5.

16 is a contact piece formed of a spring material such as phosphor bronze, and has a plurality of movable contacts 17 corresponding to the fixed terminal 8.
The movable contact 17 has a part of the side protruding in a semicircular shape and is bent to form an operating protrusion 18 in the concave part 13 and convex part 14 of the cam block 10.
It is located at a position opposite to. This contact piece 16 is fixed to the common terminal 7 of the base 5 by welding or caulking during assembly, but may be formed integrally with the common terminal 7 depending on the case.

Reference numeral 19 denotes a spring seat, which has two semicircular holes 20 for fitting into the shaft 12 of the cam block 10, and has a protruding convex portion 21 on its outer periphery. This spring seat 19 is bent toward the surface into a shallow V-shape, and when assembled, the convex portion 21 is pressed against a groove 22 provided radially on the inner surface of the case 1 corresponding to the number 3.

Each part having the above structure is assembled as follows. That is, the center hole 15 of the cam block 10 is aligned with the shaft 6 of the base 5, and the cam block 10 is
on top of the base 5, and connect the contact piece 16 to the common terminal 7.
is fixed and its movable contact 17 presses the cam block 10 from above. Shaft 1 of cam block 10
The case 1 is fixed to the base 5 by fitting the spring seat 19 into the groove 11 of the case 2, covering the case 1 from above, and fitting the fitting protrusion 9 of the base 5 into the fitting hole 4 of the case 1. Complete the assembly. This assembly work can be easily carried out because the number of parts is small and each independent part can be assembled in sequence.

Here, when the cam block 10 is rotated by applying a screwdriver or the like to the groove 11 of the cam block 10, the convex portions 21 of the spring seat 19 sequentially fit into the radial grooves 22 on the inner surface of the case 1, thereby performing a click operation. It can be set to any desired rotational position. Concave portion 13 and convex portion 1 of cam block 10
The operating protrusion 18 of the movable contact 17 comes into sliding contact with the portion 4, and when the recess 13 is located at the operating protrusion 18 as shown in FIG. is pressed against the end surface of the fixed terminal 8, the connection between the common terminal 7 and the fixed terminal 8 is turned on, and when the convex portion 14 is positioned at the operating projection 18, the movable contact 17 is pushed up and the tip is connected to the fixed terminal. 8, and the connection between the common terminal 7 and the fixed terminal 8 is turned off. Therefore, by appropriately selecting the position and size of the concave portion 13 and the convex portion 14 and the corresponding position of the operating protrusion 18 of the movable contact 17,
Common terminal 7 depending on the rotational position of cam block 10
Various combinations of on and off states can be obtained between the switch and a plurality of, for example, four fixed terminals 8, and these combinations can be detected and operated as a digital switch. In this case, since the contact state of the contacts can be directly visually inspected by rotating the cam block 10 before mounting the case 1, it is possible to easily confirm the opening/closing operation and adjust the contact pressure.

Note that the concave portion 13 and convex portion 14 of the cam block 10
It is not necessary to keep the shape constant,
For example, all movable contacts 17 as shown in FIG.
The recess 1 to be operated corresponding to the operation protrusion 18 of
3a is formed over both the outer circumference and the inner circumference, the recess 13b that should correspond only to the movable contact 17 located on the outside is formed only on the outer circumference, and the recess 13c that should correspond only to the movable contact 17 located on the inside.
is formed only on the inner periphery. Alternatively, a wide concave portion 13d may be provided in common at adjacent rotational positions. Furthermore, the relationship between the fixed terminal 8 and the movable contact 17 is not limited to that described above; for example, as shown in FIG. 7, the upper end of all or some of the fixed terminals 8 may be bent to form a bend 23. It is also possible to make the movable contact 17 turn on when it is pushed up by the convex portion 14.
Further, in the above-mentioned embodiment, all of the plurality of movable contacts 17 are included in one contact piece 16, but the movable contacts 17 are divided into two sets, and each set is provided with a common terminal 7 to form a separate circuit. You can also do that. This can be selected as appropriate depending on the necessity of the on/off combination of the common terminal 7 and the fixed terminal 8.

In the present invention, as described above, the unevenness is formed in the axial direction of the disc-shaped cam block, and the contact is opened and closed by moving the movable contact up and down in the axial direction using the unevenness. It can be made smaller than a rotary plate formed with a sliding plate with multiple contact pieces, and the structure is simple and easy to assemble, resulting in lower manufacturing costs. This makes it possible to obtain an optimal small digital switch. In addition, a plurality of radial grooves are formed on the bottom surface of the case that is placed on the cam block, and a convex portion is provided on the top surface of the outer periphery of the spring seat, which is formed by bending the plate into an approximately V-shaped cross section, and the case is mounted on the top of the cam block. Since the convex part of the spring seat is engaged with the groove on the case, the click action when rotating the cam block is caused by the convex part of the spring seat engaging the groove on the bottom surface of the case to cover the cam block. This can be achieved by sequential fitting through deformation, and in order to obtain the click action, it is only necessary to use a spring seat provided with a convex portion as a separate member, and the number of parts is not particularly increased and the spring seat is small. It can be made into a digital switch that is easy to assemble, and
The spring seat is formed by bending a plate into a V-shape so as to have spring properties.The spring seat is not bulky and allows the entire digital switch to be made thin.

[Brief explanation of the drawing]

FIG. 1 is a partially exploded perspective view of an embodiment of the present invention;
Figure 2 is a perspective view of the same case as seen from the back side, Figure 3
The figure is an exploded perspective view of the main parts, Figure 4 is a perspective view of the cam block seen from the back side, and Figure 5 is an explanatory diagram showing the operating state of the contact part, where a is the on state and b is the off state. 6 is a top view of the cam block of another embodiment, and FIG. 7 is an explanatory diagram showing the operating state of the contact portion of another embodiment, where a indicates the off state and b indicates the on state, respectively. FIG. 1...Case, 3...Number, 5...Base, 7
... common terminal, 8 ... fixed terminal, 10 ... cam block, 13 ... recess, 14 ... protrusion, 16 ...
Contact piece, 17...Movable contact, 18...Operation protrusion,
19... Spring seat, 21... Convex portion, 22... Groove.

Claims (1)

[Claims] 1. A concave part and a convex part are formed on the surface of a disc-shaped cam block in the axial direction of the cam block, and the movable contact is moved up and down in the axial direction by the concave part and convex part, thereby performing opening/closing operations with the fixed terminal. This rotary digital switch has a plurality of radial grooves on the bottom surface of the case that is placed over the cam block, and a convex portion on the top surface of the outer periphery of the spring seat, which is formed by bending a board into a roughly V-shaped cross section. A rotary digital switch characterized by a protruding spring seat attached to the top of a cam block whose convex part is engaged with a groove in a case.