JPS60738B2 - push button digital switch - Google Patents

Description

[Detailed description of the invention] The present invention relates to a push-button digital switch.

In the conventional push-button type digital switch, for example, as shown in Fig. 1, the push buttons la and lb are pressed against the spring force of the return springs 2a and 2b to operate the feed pawls 3a and 3b to move the ratchet wheel 4. The character wheel 7, which has numbers or letters printed at equal pitch intervals on its outer circumferential surface, is rotated in the forward or reverse direction and positioned by engaging the anti-reverse pawl 6 with the other pawl wheel 5. It is intermittently rotated one pitch at a time together with wheels 4 and 5. Then, the numbers or characters on the outer circumferential surface of the character wheel 7 are displayed through the display window 8a of the case 8, and the slider 9 attached to the character wheel 7 is connected to the fixed contact (
(not shown) to output an output signal corresponding to the displayed number or letter. However, in the above-mentioned push-button type digital switch, the push-button l
Since the components such as a, lb, the return springs 2b, 2b, and the feed claws 3a, 3b are each made of separate members, there is a drawback that the number of parts is extremely large and the assembly work is complicated.

In particular, in the case of small-sized push spade type digital switches, the increase in the number of parts and the complexity of assembly work are major causes of cost increases. For this reason, the push nails la, l
It is conceivable to make b into a U-shape made of synthetic resin, integrally form the feed claws 3a and 3b, and engage the cylindrical bearing part at the center of the base with the shaft of the case.

This method reduces the number of parts and assembly man-hours, but
When assembling the push peg into the case, the bearing part and shaft become strained, making it impossible to easily attach the push button to the case.Furthermore, the bearing part lifts up along the shaft while the push peg is in operation, causing damage to the plow. There is a problem in that it may cause malfunction. The present invention has been made in view of the above-mentioned conventional drawbacks, and an object of the present invention is to provide a push-button type digital switch that has a small number of parts, is easy to assemble, and is free from malfunctions.

Next, the present invention will be explained with reference to the accompanying drawings, which are one embodiment of the present invention.

In FIGS. 2 to 6, reference numeral 10 denotes a box-shaped case body made of synthetic resin, with a display window 11 and rectangular holes 12, 12 perforated on its upper surface, and cylindrical rattans 13, 1 inside.
4 is integrally provided, and a reinforcing rib 15 is provided on the lower side of the shaft 14.
is provided.

16 is a push button made of synthetic resin and integrally molded into a substantially U-shape.
Large flange portions 18, 18 are provided at the lower portions of the head portions 17a, 17b at both ends, and a semi-cylindrical bearing portion 20 is provided at the center of the base of the thin plate-like chest 19.

Feed pawls 21a, 21b and reverse prevention pawls 22a, 22b are integrally provided on the inner side of the body portion 19.
9 near the center of the bottom 19a and bent portions 19b, 19b
is medium-narrow. Therefore, the push button 16 has flexibility, and is given an upward return force by defeating the two parts 19 in a state where they are slightly in competition with each other. As shown in FIG. 5, the installation procedure involves inserting the heads 17a and 17b into the rectangular holes 12 and 12 provided on the top surface of the case body 10.
The flange portions 18, 18 are brought into contact with the inner surface of the case body 10, and the body portion 19 is manipulated to release the bearing portion 20 at the center of the bottom.
is engaged with a shaft 14 provided on the case body 10. At this time, since the bearing part 20 is semi-cylindrical, the engagement between the shaft 14 and the bearing part 20 will not be strained, and the push button 16 can be easily attached to the case body 10'. 24 is a ratchet wheel 25
It is a disc-shaped character wheel integrally provided with, and connection numbers 0 to 9 are printed at equal pitch intervals on its outer peripheral surface, depending on the number of teeth of the ratchet wheel 25.

Two protrusions 27, 27 are provided on the front side of the character wheel 24, that is, on the side opposite to the ratchet wheel 25, and a slider 28 made of a conductive metal that extends across the contact mechanism is iron-plated into the protrusion 27. Rarely, it is attached in one piece by heat caulking. letter wheel 24
By inserting the shaft 13 provided in the case body 101 through the center hole 26 of the case body 101, the case body 1 river letter wheel 24 is rotatably pivoted, and the ratchet wheel 25 is integrally provided with the pusher 16. Heads 23a of reverse prevention claws 22a, 22b,
23b is intermittently positioned by one pitch by elastically engaging the display window 11 on the top surface of the case body 10.
, a number printed on the outer peripheral surface of the character wheel 24 is displayed. 29 is a cover made of synthetic resin that is attached to the entrance of the case body 10, and a fixed contact (not shown) of a predetermined shape is printed on the inside surface of the cover, and the letter wheel 24 is printed on this fixed contact. The sliding pad 28 slides into contact to sequentially switch the contacts.

By attaching this cover 29 to the case body 10, the bearing portions 2 and 6 of the push pin 16 engaged with the shaft 14 are
As shown in the figure, the cover 29 and the case body 10 are clamped and fixed. Note that the terminal of the above fixed contact is covered with cover 29.
The extension portion 30 is exposed to the outside of the case body 10 along the inner surface. Next, the operation of the push-button digital switch having the above configuration will be explained. Now, when the head 17a of the push button 16 is pressed downward, the left half of the push button 16 in FIG. At the same time, the feed pawl 21a engages with the ratchet wheel 25 and rotates the ratchet wheel 25 and character wheel 24 together by about half in the counterclockwise direction in FIG. Rotate the pitch.

Next, when the pressing force on the push button 16 is released, the push button 16 rises due to its own return force, and the feed claw 21a moves up to the ratchet wheel 25.
While touching the tip of the tooth, it rises to a position where it no longer makes contact. On the other hand, the ratchet wheel 25 further rotates about half a pitch in the counterclockwise direction due to the slanted portion and the pressing force of the head 23b of the other reverse prevention pawl 22b, and the reverse prevention pawl 22a engages with the ratchet wheel 25. One feeding is completed by positioning.
At this time, the number of the character wheel 24 is displayed for one pitch on the display window 11 of the case body 10, and the slider 28 corresponds to this.
switches the fixed contact and outputs an output signal corresponding to the displayed number. Note that when operating the head 17a of the push button 16, the bearing 20 at the center of the base engages with the shaft 14 of the case body 10, and the case body 10 and the cover 2
Since the kimono is fixed at 9, the manipulation of the left half of the 8 part 19 by the operation of the pusher 16 will not affect the right half of the okabe 19, and furthermore, the chest 19 will not rise. .

Next, when the other head 17b of the push nail 16 is pressed downward, the pusher 16 performs the same operation as described above, and the feed claw 21
At b, the ratchet wheel 25 and the character wheel 24 are rotated together in the opposite direction to the above, that is, in the clockwise direction.

This rotation completes one feed in the opposite direction, and a display and an output signal corresponding to this feed are issued. In the above embodiment, everything other than the slider 28 and the fixed contact that constitute the contact mechanism is made of synthetic resin.
There are almost no problems caused by rust, etc., and the insulation is extremely good.

In addition, feed claws 21a, 21b, reverse prevention claws 22a, 22
b and the return spring are provided integrally with the push button 16, and the pawl wheel 25 is provided integrally with the character wheel 24, so the number of parts is halved compared to the conventional one, and assembly work is extremely easy. As is clear from the above description, according to the present invention, the push nail is made of synthetic resin into a substantially U-shape, and the feed nail is integrally molded,
The bearing at the center of the bottom is supported by the shaft of the case to give the push button maneuverability, so the feed pawl and reversal prevention pawl, which were previously separate parts, are integrated, reducing the number of parts and assembly man-hours, and reducing costs. can be achieved.

In addition, since the bearing part is formed into a semi-cylindrical shape and is sandwiched between the case and the cover, the bearing part can be easily engaged with the shaft of the case during assembly. During operation, the body can be prevented from lifting up from the case. In addition, as in the above embodiment, providing reinforcing ribs on the lower side of the rattan has the effect of imparting strength to the shaft that can withstand the pressing force of the pegs.

[Brief explanation of the drawing]

Figure 1 is a cross-sectional view of a conventional push-pin type digital switch, Figure 2
3 is a plan view of FIG. 2, FIG. 4 is an exploded perspective view of FIG. 2, and FIG. FIG. 6 is a sectional view showing a state in which the push spade is attached, and FIG. 6 is a sectional view showing a state in which the bearing portion of the pusher 0 engaged with the shaft of the case is attached between the case and the cover. 10...Case body, 11...Display window, 1
4...Shaft, 15...Reinforcing rib, 16
...Push nail, 19...Eye part, 20...Bearing part, 21a, 21b...Feeding claw, 22a, 22b...
...Reversal prevention claw, 24... Letter wheel, 25...
・Rawl wheel, 28... Tank mover, 29. ．． ...Cover o Figure 1 Figure 2 Figure 3 Figure 4 Figure 5 Figure 6

Claims (1)

[Scope of Claims] 1. A character wheel that is rotatably mounted in a case and has numbers or letters printed at equal pitches on its outer peripheral surface, and a slider that constitutes a contact mechanism that is attached to the character wheel; A ratchet wheel that rotates coaxially with the character wheel, a reversal prevention pawl that elastically engages with the ratchet wheel to intermittently position the ratchet wheel, and a flexible approximately U-shaped body. The center of the base is supported by a shaft protruding from the case, and both ends protrude outside the case, and by pressing either of the protruding ends, the ratchet wheel is rotated one pitch at a time intermittently in the forward or reverse direction. It consists of a push button with an integral claw, and a semi-cylindrical bearing part is integrally formed at the center of the bottom of the body part and projects in the same direction as the protruding direction of the shaft, and the bearing part is attached to the case and the case. A push-button type digital switch characterized by being clamped with a cover attached to an opening of the switch. 2. The push button type digital switch according to claim 1, wherein a rib is provided on the opposite side of the shaft from the direction in which both ends of the push button protrude.