JPH0717121Y2 - Time limit setting volume device - Google Patents

Description

[Detailed Description of the Invention] <Field of the Invention> This invention mounts a rotary switch having a rotatable volume body on a printed circuit board, and the volume body is rotatably mounted on a case by means of a torque spacer. The present invention relates to a time setting volume device in which a knob is detachably coupled.

<Prior Art and Problems> FIG. 3 shows an example of a conventional time setting volume device. As shown in the figure, a rotary switch A is electrically connected and fixed to the printed circuit board 11. That is, on the main surface of the resistor substrate 12 made of a semiconductor, a conductive layer 19a,
An arcuate resistor layer 19b centered on the conductive layer 19a is formed. A terminal 13a is electrically connected to the central conductive layer 19a, and terminals 13b and 13c are electrically connected to both ends of the outer resistor layer 19b so as to project from the substrate 12.

A volume body 16 is rotatably mounted on the substrate 12 via a seal ring 15.
A slider 18 is fixed to the lower portion of 16. This slider 18
Protrusions 18a and 18b are formed at the lower ends of both ends of the inner protrusion 18a.
Is always in sliding contact with the central conductive layer 19a, and the outer protrusion 18b is configured to rotate while slidingly contacting the outer resistor layer 19b around the protrusion 18a.

The volume body 16 is covered with a cover 17 attached to the resistor substrate 12.

The terminals 13a, 13b, 13c of the rotary switch A are penetrated through the terminal holes of the printed circuit board 11 and the tips thereof are fixed by the brazing portion 14.

The printed circuit board 11 is fixed to the case 21 in a state where the rotary switch A having the above structure is mounted. The main surface of the case 21 is arranged to face the volume body 16 at a predetermined interval, and a knob mounting hole is formed in the main surface of the case 21.
22 are formed. A torque spacer 23 is rotatably mounted in the knob mounting hole 22 of the case 21, and the torque spacer 23 has a recess for rotating the volume main body 16.
An engaging projection 24 is provided on the 20 so as to be engageable with and disengageable in the rotation axis direction.

In the torque spacer 23, one is provided on the outer peripheral portion of the engaging convex portion 24.
A pair of through holes 26 are formed, and a hook 28 protruding from a knob 27 is fitted into each of these through holes 26, and can be engaged with and disengaged from the inner peripheral edge portion 22a of the knob mounting hole 22 of the case 21. And the volume main body 16 is configured to be rotated integrally with the knob 27 via the torque spacer 23.

A nameplate 25 is fixed between the case 21 and the knob 27 to rotatably prevent the torque spacer 23 from coming off.

When assembling the time setting volume device,
The rotary switch A is electrically connected and fixed to the printed circuit board 11 on the base side as shown in the figure. On the other hand, in another process,
A torque spacer 23 and a knob 27 are rotatably mounted in the knob mounting hole 22 of the case 21, and a hook 28 protruding from the knob 27 passes through a through hole 26 of the torque spacer 23 to make the case 21 An inner peripheral edge portion 22a of the knob mounting hole 22 is detachably engaged, and a nameplate 25 is fixed between the case 21 and the knob 27 to rotatably prevent the torque spacer 23 from coming off.

After that, the printed circuit board 11 is fixed to the case 21 with the rotary switch A attached, and at this time, the engaging protrusion 24 of the torque spacer 23 is rotated in the rotating operation recess 20 of the volume main body 16 in the rotating shaft direction. Are removably engaged with each other to couple them.

In the above structure, when the knob 27 is rotated, the volume body 16 and the slider 18 are integrally rotated, and the slider is rotated.
While the inner protrusion 18a of 18 is always in sliding contact with the central conductive layer 19a, the outer protrusion 18b is rotated while slidingly contacting the conductive layer 19b,
The electric resistance value between the conductive layer 19a and the conductive layer 19b is sequentially changed, and a voltage corresponding to the change in the resistance value is applied to a control circuit (not shown) to set the time limit.

However, according to the above configuration, after the time setting volume control device is assembled as a timer (not shown), the hook 28 of the knob 27 is displaced inward due to an impact during dropping or transportation or other handling. However, there is a problem in that the knob 27 is detached from the inner peripheral edge portion 22a of the knob attachment hole 22 and the knob 27 is detached from the torque spacer 23.

<Purpose of the Invention> The present invention has been made to solve the above problems, and an object thereof is to provide a time setting volume device that can prevent the knob from falling off very simply and easily.

<Structure and effect of device> The time setting volume device according to the present invention has a rotary switch electrically connected and fixed to a printed circuit board and a knob mounting hole facing the volume body of the rotary switch at a predetermined interval. A formed case, a torque spacer rotatably mounted in a knob mounting hole of the case and detachably engaged with the volume body, and having a plurality of through holes in an outer peripheral portion of the engaging portion, A knob having a hook fitted into the through hole, rotatably coupled to the torque spacer integrally, and engaged with an inner peripheral edge portion of the knob mounting hole of the case; It is characterized in that a stopper portion for preventing engagement of the hook engaged with the inner peripheral edge portion is provided so as to project from the volume main body.

According to this invention, since the stopper portion of the volume main body is disposed opposite to the inside of the hook protruding from the knob, the hook is prevented from falling inside the knob mounting hole due to a drop or impact during transportation or other handling. It is possible to effectively prevent separation from the peripheral portion.

Further, it is possible to achieve that the hook of the knob is separated from the inner peripheral edge of the mounting hole with an extremely simple structure in which the stopper portion is provided to project on the volume body without increasing the number of parts. Assembly work is also easy.

<Description of Embodiments> An embodiment of the present invention will be described below with reference to the drawings.

FIG. 1 is a sectional view showing an example of a time setting volume device according to the present invention.

1 is different from FIG. 3 in that a stopper portion 31 for preventing the hook 28 of the knob 27 from being separated from the inner peripheral edge portion 22a of the knob mounting hole 22 is provided on the volume main body 16 in a protruding manner. is there.

That is, a pair of projections 31 are provided on the volume body 16 so as to be located on the outer periphery of the engaging portion of the volume body 16 with the torque spacer 23 and to face the inside of the hook 28.
Is provided.

Since the other structures are similar to those described in the conventional example of FIG. 3, the same parts are designated by the same reference numerals, and detailed description thereof will be omitted.

When assembling the time setting volume device,
As shown in FIG. 2, the rotary switch A is electrically connected and fixed to the printed circuit board 11.

On the other hand, in a separate step, the torque spacer 23 and the knob 27 are rotatably attached to the knob mounting hole 22 of the case 21,
The hook 28 protruding from the knob 27 is the torque spacer 23.
Through the through hole 26, is engaged with the inner peripheral edge portion 22a of the knob mounting hole 22 of the case 21 in a disengageable manner, and the nameplate 25 is fixed between the case 21 and the knob 27, and the torque The spacer 23 is rotatably retained.

After that, the printed circuit board 11 is fixed to the case 21 with the rotary switch A attached, and at this time, the engaging protrusion 24 of the torque spacer 23 is rotated in the rotating operation recess 20 of the volume main body 16 in the rotating shaft direction. Are removably engaged with each other to couple them. At the same time, the hook of knob 27 above
The protrusions 31 of the volume body 16 are arranged inside the 28 so as to face each other.

As a result, the time setting volume device is assembled as shown in FIG.

According to the above configuration, since the stopper portion 31 of the volume main body 16 is disposed inside the hook 28 protruding from the knob 27, the hook 28 may be dropped or impacted during handling such as transportation. Inner peripheral edge portion 22a of the knob mounting hole 22
It is possible to effectively prevent the knob 27 from falling off after being detached.

Further, the hook 28 of the knob 27 is the inner peripheral edge portion 22 of the mounting hole 22.
The detachment from a can be achieved without increasing the number of parts by a very simple structure in which the stopper portion 31 is provided to project from the volume body 16, and the assembling work is also easy.

In the above embodiment, the engagement structure between the torque spacer 23 and the volume body 16 is the volume body.
Although the concave portion 20 for rotating operation is formed in 16 and the engaging convex portion 24 is formed in the torque spacer 23, it goes without saying that the above-mentioned concavo-convex relationship may be reversed.

[Brief description of drawings]

FIG. 1 is a sectional view showing an example of a time setting volume device according to the present invention, FIG. 2 is a sectional view for explaining an example of the assembling work, and FIG. 3 is a sectional view showing a conventional example. A …… Rotary switch, 11 …… Printed circuit board, 16 ……
Volume body, 20 …… Rotating operation part, 21 …… Case, 22
...... Knob mounting hole, 22a …… Inner peripheral edge part, 23 …… Torque spacer, 24 …… Engagement part, 26 …… Through hole, 27 …… Knob, 28
…… Foot, 31 …… Stopper section.

Claims (1)

[Scope of utility model registration request] 1. A printed circuit board, a rotary switch having a rotatable volume body electrically connected to and fixed to the printed circuit board and having a rotary operation portion at a central portion, and the printed circuit board is attached to the rotary switch. A case in which knob mounting holes that are opposed to each other at a predetermined interval are formed in the volume body, and a case that is rotatably mounted in the knob mounting hole of the case and is mounted on a rotation operation portion of the volume body in a rotation axis direction. A torque spacer having an engaging portion that is removably engaged and a plurality of through holes on the outer peripheral portion of the engaging portion; and a torque spacer that is fitted into the through hole and is rotatable integrally with the torque spacer. A time setting volume device having a knob having a hook that is coupled to and is engaged with the inner peripheral edge of the knob mounting hole of the case, and engages with the inner peripheral edge of the knob mounting hole. Timed setting volume and wherein the projecting from the said volume body an a stop portion for preventing engagement of the hook that.