JPH0214100Y2 - - Google Patents

Description

[Detailed Description of the Invention] This invention relates to a digital switch, and particularly to a structure that allows the digital switch to be easily miniaturized.

Conventionally, this type of digital switch has, as shown in FIG. 3a in case 1
A rectangular hole (not shown) is formed to make the number wheel 2 protrude further, and a support shaft 1a is provided at the center of the inner wall to insert into a through hole 2b provided in the number wheel 2 and support the number wheel 2. There is a stopper piece 5 at the bottom.
The step arm 3 has an inner arm 3C branched from the lower part of the outer arm 3b and is arranged symmetrically with respect to a gear-shaped cam part 2a provided on the number wheel 2. A spring 4 is interposed between the spring receiving part 3e at the lower end and the case 1, and the pressing part 3a is arranged so as to protrude from the case 1 so as to be movable up and down. In addition, the stopper piece 5 has a spring 6 interposed between the crest 5a and the spring receiving piece 1c of the case 1, so that a part of the ridge 5a is attached to the case 1.
At the same time, the peak portion 5a is arranged to face the valley of the teeth of the cam portion 2a of the number wheel 2. This is done by contacting and locking the locking piece 5b. Further, when the step arm 3 is pressed once on the push button portion 3a, the feed pawl 3d provided at the tip of the inner arm 3c comes into contact with the teeth of the cam portion 2a of the number wheel 2, rotating the number wheel 2 one pitch. Therefore, the number wheel 2 can be moved by one press operation.
is a step forward.

However, when downsizing the structure as described above, there are problems such as the problem of space to store the spring 5 depending on the size of the spring 5, and the problem of spring force where the spring force becomes weaker if the spring 6 becomes smaller. Was.

This invention was proposed to improve the above-mentioned drawbacks, and has a locking part provided on the case and an engaging part that engages with the locking part, and is arranged opposite to the gear part of the number wheel. It is an object of the present invention to provide a digital switch which can be easily downsized by housing and arranging an elastic member having a pressing part in a recess provided in a number wheel.

This invention will be explained below based on an embodiment shown in FIGS. 2 to 4. Components that are the same as those in FIG. 1 are designated by the same reference numerals.

Reference numeral 1 denotes a case, and the front side is provided with a display window 1e through which the numbers on the number wheel 2 can be viewed, and a rectangular hole 1f through which the push button portion 3a of the step arm 3 projects outside from the case 1. In the upper part, there is a recess 1 in which the locking parts 9a of the elastic member 9 are locked.
A locking protrusion 1g having a diameter of 1h and 1h and a support shaft 1a that is inserted into a through hole 2b provided in the number wheel 2 and supports the number wheel 2 are formed, and a stopper piece 5 is provided at the bottom.
A hole 1c into which a part of the peak portion 5a of the stopper piece 5 is inserted, and limiting protrusions 1b, 1b of the stopper piece 5 are formed.

The number wheel 2 has 10 numbers from 0 to 9 printed at equal intervals on its outer peripheral wall, and on one side, when the number wheel 2 rotates, it slides over a circuit pattern printed on the printed circuit board 8. A movable contact 7 that moves is attached, and the sliding of this movable contact 7 causes the display window 1e to open.
A signal corresponding to the number displayed is output to the printed circuit board 8. Further, a recess 2c is formed on the other side, a gear-shaped cam portion 2a is formed within this recess 2c, and a through hole 2b is provided at the center of this cam portion 2a. Then, the support shaft 1a of the case 1 is inserted into the through hole 2b, and the locking protrusion 1g of the case 1 and a part of the peak 5a of the stopper 5 are arranged so as to fit into the recess 2c of the number wheel 2. .

The step arm 3 has an inner arm 3c branched from the lower part of the outer arm 3b, which is arranged symmetrically with respect to the cam part 2a of the number wheel 2, and between the spring receiver part 3e at the lower part of the step arm 3 and the case 1. The push button part 3 is made vertically movable through the interposition of a spring 6.
a is arranged so as to protrude from a rectangular hole 1f provided on the front surface of the case 1, and a rotating feed claw 3d is provided at the tip of the inner arm 3c.

The stopper piece 5 consists of a mountain part 5a and a locking piece 5b, and a groove 5c is provided at the bottom of the mountain part 5a.
A part of the peak 5a is inserted into the hole 1b of the case 1, and the pressing part 9 of the elastic member 9 is inserted into the groove 5c of the peak 5a.
b is inserted so that the peak portion 5a is positioned opposite to the valley between the teeth of the cam portion 2a of the number wheel 2. Further, the stopper 5 prevents the number wheel 2 from reversing by bringing the peak 5a into contact with the cam portion 2a of the number wheel 2, and the stopper 5 prevents the number wheel 2 from reversing.
By bringing the locking piece 5b into contact with the spring 6, the upward extension is restricted by the spring 6.

The elastic member 9 has a substantially ring shape and is formed of a linear spring, and has locking portions 9a, 9a provided at both ends, and a pressing portion 5b facing inward at a position facing the locking portions 9a, 9a. It has been formed.

When the push button 3a of the step arm 3 is pressed once in the digital switch as described above, the feed pawl 3d of the inner arm 3c moves to the number wheel 2.
The cam portion 2a is rotated by contacting the teeth of the cam portion 2a. The teeth of the cam part 2a press the stopper piece 5 downward against the force of the linear spring 9, and when the teeth get over the peak part 5a, the stopper piece 5 pushes the cam part 2a by the force of the linear spring 9. Press upward to release the cam part 2a.
It is stabilized by being located opposite to the valley of. Therefore, the cam portion 2a has rotated one pitch, and the number wheel 2
is a step forward.

As described above, the locking protrusion provided on the case 1 and the locking parts 9a, 9a that lock on the locking protrusion 1g.
Since the linear spring 9 is configured to fit into the recess 2c of the number wheel 2, the linear spring 9, which has a pressing portion 9b that fits into the groove 5c of the gear-like cam portion 2a of the number wheel 2, is inserted into the recess 2c of the number wheel 2.
This not only solves the space problem and the problem of the spring force of the spring 6, but also has practical effects such as easy assembly and miniaturization of the digital switch. .

[Brief explanation of the drawing]

FIG. 1 is a partially sectional front view of a conventional embodiment, and FIG. 2 is an exploded sectional view of an embodiment according to this invention.
FIG. 3 is a partially sectional front view of an embodiment of the invention, and FIG. 4 is a partially sectional side view. 1... Case, 1a... Support shaft, 1g... Locking protrusion, 1h... Recess, 2... Number wheel, 2a... Gear-shaped cam part, 2b... Through hole, 2c... Recess , 3...
Step arm, 3a...push button part, 3d...feeding pawl, 9...elastic member, 9a...locking part, 9b...
Pressing part.

Claims (1)

[Scope of utility model registration request] A case having a locking protrusion and a limiting protrusion on the inner wall, a number wheel with N symbols marked on the outer peripheral surface, a recess on one side, and a gear-shaped cam part formed in the recess. , a ring-shaped elastic member having locking parts at both ends and a pressing part formed in a part, and a ridge part on the upper part that abuts the gear-shaped cam part, and is disposed on the limiting protrusion of the case. It consists of a stopper piece for preventing reversal that restricts vertical movement, and the locking part of the elastic member is locked to the locking protrusion of the case, and the pressing part is disposed opposite to the lower part of the stopper piece. A digital switch characterized in that the number wheel is arranged in the case so that the locking protrusion and the elastic member fit into a recess of a car.