JPH0430746Y2 - - Google Patents

Description

[Detailed Description of the Invention] <Technical Field of the Invention> This invention relates to a push-operated digital switch used for setting clocks and temperature counts in electronic equipment, sequencers, measuring instruments, and the like.

<Background of the invention> As shown in FIG. 5, for example, a conventional digital switch of this type has a case 5, a pair of push-type operating shafts 6, 6a, a letter 70 on the outer circumferential surface, and a central boss portion. Ratchet gear 7 on the outer periphery of
There is one that incorporates a character wheel 7 that forms a numeral 1. A contactor unit (not shown) is connected to the conductive pattern on the side surface of the character wheel 7, and when the character wheel 7 is rotated forward or backward by pushing the operation shafts 6, 6a, the contactor unit (not shown) is connected to the conductive pattern on the side surface of the character wheel 7. The contacts of the unit are switched to output a digital signal corresponding to the character.

However, since the operating shafts 6, 6a and the return leaf spring 8 located inside the case 5 are separate parts, the number of parts not only increases and assembly is time-consuming, but also makes it difficult to assemble the switch from an assembly and functional perspective. There were limits to miniaturization.

Therefore, the applicant recently proposed a method in which a synthetic resin molded body having push buttons at both ends is integrally formed into a substantially U-shape, and the synthetic resin molded body is placed on a shaft inside a case with its body slightly bent. (Japanese Patent Application Laid-Open No. 54-39880).

However, with this type of structure, although it is possible to reduce the number of parts, sufficient return force cannot be obtained, and the product is supported at one point in an unreasonable flexing position, resulting in deformation and damage to the body and bottom. There are problems such as ease of use.

<Purpose of the invention> This invention was made by focusing on the above-mentioned problems, and aims to provide a digital switch that can reduce the number of parts, provide sufficient return force, and prevent deformation and damage. With the goal.

<Structure and Effects of the Invention> The digital switch according to the invention includes a case in which a character wheel with characters arranged on its outer circumferential surface is rotatably disposed on a shaft, and an operating member is connected to the character wheel. A digital signal corresponding to the character is output by rotating the character wheel by one pitch in forward and reverse directions using an operating member.

The operating member integrally includes a push button portion at one end of a pair of parallel slide shafts, and a spring portion curved inwardly into a U-shape at the other end, and the two spring portions are integrally connected via a mounting plate. In addition, a feed pawl for rotating the character wheel forward and backward and a braking piece for stopping the character wheel in a fixed position are integrally formed on the opposing surface of each slide shaft, and the push button portion protrudes outside the case. The operating member is housed in the case by positioning and fixing the mounting plate to the wall surface of the case.

According to the structure of this invention, an operation member integrally equipped with a push button part and a spring part is connected to a character wheel, and the character wheel is rotated by pushing the operation member, so compared to the conventional example. As a result, the number of parts is reduced, assembly work becomes easier, and the switch can be made smaller.

In addition, by simply assembling the operating member into the case, protruding each push button part from the hole to the outside of the case, and fixing the mounting plate to the wall inside the case, the feed pawl and brake piece can be positioned corresponding to the set position of the character wheel. Since the assembly is completed, assembly work is labor-saving and consistent products can be provided at low cost.

Furthermore, since the spring part is curved inward in a U-shape, sufficient return force can be obtained, and the operating member is stably supported on the wall, preventing deformation or damage to the slide shaft or mounting plate. There is no risk of inviting it.

In addition, when the push button is pressed, only the corresponding U-shaped spring section flexes and deforms, and the mounting plate is joined to the wall of the case and does not deform, so both push buttons can be operated independently of each other and the feed The practical effects are remarkable, such as the smooth movement of the pawls and brake pieces.

<Description of Embodiment> FIGS. 1 to 4 show a digital switch according to an embodiment of this invention.

This digital switch includes a character wheel 2 having a conductive pattern on the side surface into a case 1 having a side opening;
Rotate this character wheel one pitch in the forward and reverse directions,
In addition to incorporating a so-called stepping operation member 3, the opening surface of the case 1 is closed by a contact unit 4 having a fixed contact 41.

The case 1 is a synthetic resin molded body in which a front wall 11, a rear wall 14, an upper wall, and a lower wall are integrally formed around a side wall 10 forming the bottom surface, and the front wall 11 has a transparent plate 18 in the center. The fitted display window 12 has holes 13, 13 formed on both sides thereof, and a protrusion 15 and a pivot 17 are integrally formed on the rear wall 14 and the side wall 10, respectively.

The character wheel 2 is a synthetic resin molded body having a cylindrical portion 21 protruding like a brim from the outer circumference of the circular base plate 20 and a pivot hole 22 opened at the center of the plate surface. A conductive pattern 23 is applied, and letters 24 from 0 to 9 are arranged on the outer peripheral surface of the cylindrical portion 21 according to the conductive pattern. A ratchet gear 25 having a number of teeth corresponding to the number of characters is integrally formed on the outer periphery of the boss portion surrounding the pivot hole 22, and by inserting the pivot 17 of the case 1 into the pivot hole 22, the character can be adjusted. The car 2 is pivoted so that it can rotate forward and backward.

The operating member 3 is an elastic synthetic resin molded body, and includes a pair of parallel slide shafts 3a and 3b with an interval between the holes 13 and 13 of the case 1. Step 30 at one end
Thin shaft-like push button parts 31a, 31b are connected to the spring parts 32a, 32 curved in a U-shape toward the inner case at the other end.
b are integrally connected to each other, and both spring portions 32a and 32b are connected to each other via a mounting plate 33. The opposing surfaces of each slide shaft 3a, 3b are provided with feed pawls 34a, 34b, and a V-shaped protrusion 3 whose tip engages the ratchet gear 25 of the character wheel 2.
Braking pieces 35a and 35b each having a diameter of 6 are provided symmetrically in a protruding manner.

This operation member 2 is inserted into the step part 30 by inserting both push button parts 31a and 31b into the extraction holes 13 and 13 from inside.
is attached to the wall surface, both spring parts 32a, 32 are slightly compressed, and the mounting plate 33 is attached to the inner surface of the rear wall 14, and is incorporated into the case 1.
a and 34b position the ratchet gear 25 at a position suitable for forward and reverse rotation, and both brake pieces 3
5a, 35b on the ratchet gear 25.
The character wheel 2 is stopped in a fixed position by meshing with vertically symmetrical gear grooves 26, 26 at the rear of the character wheel 2, respectively.

Next, the operation of the digital switch having the above configuration will be explained. When one of the push button parts 31a is pressed as shown in FIG. On the other hand, the feed pawl 34a applies a rotational force to the ratchet gear 25. At this time,
As the ratchet gear 25 rotates, the brake piece 35b of the other slide shaft 3b is bent upward as the engaged protrusion 36 is pushed out of the gear groove 26, and the feed pawl 34a pushes the ratchet gear 25 tightly. At this time, the tip of the teeth of the ratchet gear 25 has just passed the top of the protrusion 36, and the protrusion 36 receives the elastic restoring force of the brake piece 35b and engages with the rear gear groove 26a as shown in FIG.

In this way, the character wheel 2 integrated with the ratchet gear 25 has the feed pawl 34a and the brake piece 35b.
The display window 12 rotates one pitch due to the deflection restoring force of
The characters 24 on the character wheel 2 are displayed in increments of one pitch, and in response to this, the conductive pattern 23 switches the contact of the fixed contact 41 to output a digital signal corresponding to the displayed number.

Next, when the other push button portion 31b is pressed, the slide shaft 3b performs the same operation as described above, rotates the character wheel 2 integrated with the ratchet gear 25 in the opposite direction, and displays and displays characters corresponding to this reverse rotation. A signal is output. Note that when pushing the push button parts 31a and 31b, the U-shaped spring parts 32a and 32
Only part b is bent and deformed, and the mounting plate 33 is not deformed because it is joined to the rear wall 14 of the case 1.Moreover, the fixed position is maintained by the engagement between the protrusion 15 and the recess 37, so that both push buttons are bent and deformed. 31a and 31b can be operated independently of each other, and the feed claws 34a and 34b and the brake piece 35
Smooth operation of a and 35b is realized.

[Brief explanation of the drawing]

FIG. 1 is a side view showing the internal structure of a digital switch according to an embodiment of the invention, FIGS. 2 and 3 are internal side views showing operating conditions, and FIG. 4 is an exploded perspective view of the digital switch. FIG. 5 is a diagram showing the internal configuration of a conventional digital switch. 1...Case, 2...Character wheel, 24...Character,
25... Ratchet gear, 3... Operation member, 3
a, 3b...Slide shaft, 31a, 31b...Push button part, 32a, 32b...Spring part, 33...Mounting plate, 34a, 34b...Feed claw, 35a, 35b
...Brake piece.

Claims (1)

[Scope of Claim for Utility Model Registration] (1) A letter wheel with letters arranged on its outer circumferential surface is rotatably disposed on a bearing inside the case, and an operating member is connected to the letter wheel, and the operating member is connected to the letter wheel. In a digital switch that outputs a digital signal corresponding to the character by rotating a character wheel one pitch in forward and reverse directions, the operating member has a push button part at one end of a pair of parallel slide shafts, and a push button part at the other end. It is equipped with a spring part that is curved inward in a U-shape, and the two spring parts are connected together through a mounting plate, and a character wheel is mounted on the opposing surface of each slide shaft for forward and reverse rotation. A feed pawl that moves the button and a brake piece that stops the character wheel in a fixed position are integrally formed, and the push button part is made to protrude outside the case, the mounting plate is positioned and fixed to the wall surface of the case, and the operating member is inserted into the case. A digital switch that accommodates (2) The digital switch according to claim 1, wherein the operating member is a synthetic resin molded body.