JPH0234402B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to rotary switches used in low current electronic circuits, and more particularly to compact programmable rotary switches that are inserted directly into printed circuit boards.

Conventionally, a small display rotation switch that can be directly inserted into a printed circuit board has been proposed as a program setting means for data input devices connected to digital electronic equipment such as computers, test equipment, process control equipment, and medical equipment. has been done. As an example of this proposal, U.S. Pat. No. 4,107,482 discloses a first rotary switch having the following configuration. The first rotary switch has an electrically insulative housing having a plurality of holes formed therein, an electrically insulative base, and rigidly coupled to the electrically insulative base in a spaced and aligned manner;
a plurality of electrical contacts passing through the electrically insulating base; and a plurality of electrical contacts provided at the uppermost end of each of these electrical contacts, inserted into respective holes inside the electrically insulating housing, and connected to the holes. a mooring harpoon that locks the electrically insulating housing to the electrically insulating base by engagement; an electrical contact means within the electrically insulative housing; and an electrical contact means provided within the electrically insulative housing. rotating means for selectively switching the electrical connection between said electrical contacts by abutting said electrical contacts.

In the case of the first rotary switch, the electrical contacts are also used to lock the electrically insulating housing to the electrically insulating base, so that during insertion of this rotary switch into the printed circuit board and When changing state settings, etc., a mechanical load that causes plastic deformation that impairs the electrical contact performance of the rotary switch is likely to occur.

Also, in U.S. Patent No. 4107482, the above-mentioned
As more specific rotary switches, second and third rotary switches having the following configurations are disclosed.

The second rotary switch has an electrically insulating enclosure in which a cylindrical hole is formed, a serration that is a part of this electrically insulating enclosure and is located around the cylindrical hole, and a serration that is located around the cylindrical hole. , a detent spring having a protrusion that engages in a selected manner, a radial cam having a plurality of ropes formed therein, an axially rotating rotor housed in the cylindrical hole, and a circumferential position of the rotor; It has a protrusion that shows
a diametrically extending web mechanically driving the detent spring; An electrically conductive beam having an electrical contact, a fixed member provided between each pair of electrical contacts, and a web to which an external mechanical force is applied between the fixed member and the adjacent electrical contacts. wherein the lobes of the radial cam mechanically contact the electrically conductive beam, thereby applying an external mechanical force to the web of the electrically conductive beam, thereby causing the stationary member and the electrical contact to It is characterized by cutting off electrical contact with at least one of the above.

In the case of the second rotary switch, there are many valleys of the serrations that are not engaged with the protrusions of the detent spring. Dust can easily enter the rotary switch, thereby impairing the electrical contact performance of the rotary switch.

The third rotary switch has an electrically insulating envelope in which a cylindrical hole is formed, a radial cam in which a plurality of lobes are formed, and an axially rotating rotor housed in the cylindrical hole. , a plurality of pairs of electrical contacts fixed in a straight line at intervals around the rotor in the electrically insulating enclosure, and a fixed member provided between each pair of electrical contacts. and an electrically conductive beam having a web to which an external mechanical force is applied between adjacent electrical contacts, the electrically conductive beam being arranged to engage and disengage the electrical contact at one end. a first portion, a driven cam portion formed at the other end of the first portion and contacting the radial cam, and a driven cam portion formed at the other end of the first portion;
a second part attached to the first part at right angles to the part;
The second part in contacting engagement with the fixed member is characterized in that it provides an electrical contact pressure while an external mechanical force is applied.

In the case of the third rotary switch, the electrical contact end of the electrically conductive beam to the electrical contact and the mechanical contact end to the radial cam of the rotor are connected to a fixed member supporting the electrically conductive beam. On the other hand, the opposing positions complicate the structure of the electrically conductive beams, thereby impairing the reliability of the rotary switch.

An object of the present invention is to provide a highly reliable rotary switch.

Another object of the present invention is to provide a rotary switch with stable electrical contact performance. In this rotary switch, the fixed electrical contacts to be connected or disconnected are not subjected to mechanical loads for assembling the switch housing and base.

Further, according to another aspect of the rotary switch,
The movable electrical contact part and the mechanical operating end of the torsion coil spring-like movable electrical contact are provided on the same side with respect to the coil part of the movable electrical contact, thereby ensuring stable electrical contact performance. Ru.

Another object of the present invention is to provide a rotary switch with excellent dustproof effects. In this rotary switch, a hole in the housing from which a manual rotary drive part of the rotor for mechanically operating a movable electrical contact protrudes is connected to a detent mechanism provided between the bottom surface of the rotor and the base. It is blocked by the upper surface of the rotor because the rotor is pushed up via the locking spring. This prevents dust from entering the rotary switch.

Hereinafter, preferred embodiments of the present invention will be described in detail with reference to the drawings. As shown in FIG. 1, the rotary switch 1 is entirely surrounded by an electrically insulating housing 2 and a base 3.

The housing 2 is made of synthetic resin, has a box shape that exhibits some elasticity, and has a rectangular top plate 4 with almost no difference in length between long and short sides.
and four rectangular side plates 5. That is, the housing 2 does not have a bottom plate.

The length of the short side of the rectangular side plate 5 is
It is approximately 1/2 the length of the long side of the rectangular top plate 4.
A circular hole 6 is formed in the center of the top plate 4.
Around this circular hole 6, ten code numbers 7 are arranged at equal intervals, each representing the electrical connection state of the rotary switch 1 into ten codes.

A rotary switch 1 is installed at one corner of the top plate 4.
A notch 8 is provided for easily indicating the setting direction.

As shown in FIG. 2, the inner surface of the top plate 4 of the housing 2 has two rows of circular recesses 9 (in this embodiment,
3 pieces) are formed. The inner ends of the terminal pins 31, 32 and 33 are fitted into the circular recess 9.

Further, as shown in FIG. 3B, a pair of base hooking portions 12 are formed on the inner surface of the lower end portions of the pair of opposing side plates 5 of the housing 2.
Each of these base hooks 12 has an insertion guide slope 13 at its lowermost end, and in continuous relationship with these insertion guide slopes 13,
each having an upwardly facing base mounting surface 14, each having a base fixing vertical surface 15 in continuous relation to these base mounting surfaces 14, and each having a base fixing vertical surface 15 in continuous relation to these base fixing vertical surfaces 15; It has a base fixing slope 16. When the base 3 is press-fitted into the base latching parts 12 while contacting the insertion guide slope 13, these base latching parts 12 are slightly bent so as to expand outward due to the elasticity of the housing 2. .

The base 3 is made of synthetic resin, and has a pair of vertical surfaces 17 and 18 on the side surfaces of the lower end opposite to each other corresponding to the pair of base hooks 12, and these vertical surfaces. It has a hooking part 20 consisting of a slope 19 between 17 and 18.
By press-fitting the hooking portion 20 of the base 3 into the base hooking portion 12 of the housing 2 and being hooked to the base hooking portion 12 as shown in FIG. 3B, the base 3 is , and is fixed so that the vertical play is removed.

Ribs 21 extend laterally on the other pair of lower end side surfaces of the base 3. This rib 21
The housing 2 is positioned between the housing 2 and the base 3 by engaging with a pair of slots 22 provided on the inner surface of both lower ends of the housing 2, thereby positioning the first and second rotors 23a and 23b.
The correspondence between the rotational position of the housing 2 and the coded number 7 on the top plate 4 of the housing 2 is ensured in a predetermined manner.

An annular recess 24 is formed in the center of the base 3, and a radial tongue piece 26 facing a pair of substantially annular detent springs 25 is supported in the center of the annular recess 24. A flange portion 27 is formed. A fixed shaft 28 for rotor rotation is implanted in the center of the flange portion 27, which is the center of rotation of the first and second rotors 23a and 23b.

In the annular recess 24, the flange portion 2
7, as shown in FIGS. 1 and 4, there are first and second rotors 23a and 23b.
Detent peaks 29 and detent troughs 30 for detent are formed radially at equal angular intervals.
These detent peaks 29 and detent valleys 30
are respectively 10 in this embodiment.

The surface of the base 3 is divided into four areas of different heights.

The base 3 has three fixed electrical contacts located close to the hooks 20 on both sides thereof.
The terminal pins 31, 32, and 33 are implanted in a straight line. These terminal pins 31,3
2 and 33 penetrate the base 3 in its thickness direction and protrude above the surface of the base 3 and below the bottom surface.

In addition, these terminal pins 31, 32 and 33
is fixed to the base 3 by being press-fitted into the base 3.

The terminal pins 31, 32, and 33 are all made of copper alloy, and have gold plating on their surfaces.

A coil portion 34a of a movable electrical contact 34 in the form of a torsion coil spring is fitted onto the terminal pin 32 located in the middle of each row. This movable electrical contact 34 is also made of copper alloy, and its surface is plated with gold.

In the movable electrical contact 34, the portion extending left and right from the coil portion 34a is bent at an angle of 90° or less in the middle, and further bent inward at the tip to form a ring. .

In the movable electrical contact 34, the left and right portions bent by 90 degrees or less constitute one movable electrical contact portion 34b and the other movable electrical contact portion 34c, respectively. These movable electrical contact portions 34b and 34c are attached to the terminal pins 31 and 33, respectively, under initial stress so as to be able to come into contact with and detach from the terminal pins 31 and 33, respectively.

In the movable electrical contact 34, the left and right portions bent inward to form a ring constitute one mechanical operating end 34d and the other mechanical operating end 34e, respectively. ing.

The movable electrical contact 34 has the shape of a torsion coil spring, and is assembled between the three terminal pins 31, 32, and 33 with initial stress present, so that both mechanical operation ends 34d and 34e is not mechanically operated by either the first or second rotor 23a or 23b,
The coil portion 34a is in electrical contact with the terminal pin 32, and one movable electrical contact portion 34b is in electrical contact with the terminal pin 3.
1 and the other movable electrical contact 3
4c electrically contacts the terminal pin 33. That is, the rotary switch 1 is a normally closed switch.

The two pairs of mechanically operating ends 34d and 34e
are formed on the first and second rotors 23a and 23b, respectively, and are arranged in four stages.
Each of the third and fourth radial cams 35, 36, 37, and 38 is mechanically operated. As a result, the terminal pin 32
is in an electrically disconnected relationship with both terminal pins 31 and 33 at the same time, is in an electrically connected relationship with either one of the terminal pins 31 and 33, or is in an electrically connected relationship with either of the terminal pins 31 and 33. Electrical connection is established for both at the same time.

Like the housing 2 and base 3, the first rotor 23a is also made of electrically insulating synthetic resin. This first rotor 23a has a manual rotation part 40 provided with a thread groove 39 at its upper end.
An arrow 41 is formed at one end of the thread groove 39. This arrow 41 is for indicating which one of the ten coded numbers 7 from 0 to 9 should be set.

A first radial cam 35 is formed below the manual rotation section 40 . A second radial cam 36 is formed below the first radial cam 35. Two circular grooves 42 are formed on the lower surface of the second radial cam 36 so as to face each other with respect to the central axis of the first rotor 23a.
Two cylindrical bosses 43 formed on the upper surface of the third radial cam 37 of the second rotor 23b are inserted into these circular grooves 42, respectively. Thereby, the first and second rotors 23a and 23b are positioned relative to each other.

A cylindrical boss 44 is formed on the lower side of the second radial cam 36. This cylindrical boss 44 has
The fixed shaft 28 for rotating the rotor of the base 3 is fitted inside, and the cylindrical boss 44 is fitted into the center hole 45 of the second rotor 23b.

The second rotor 23b is also made of electrically insulating synthetic resin like the housing 2 and base 3. The second rotor 23b has a third radial cam 37 at its upper end, a fourth radial cam 38 continuous to the third radial cam 37, and a fourth radial cam 38 on the lower side of the fourth radial cam 38. It has a flange portion 46 that comes into contact with a part of the upper surface of the detent spring 25, and has a detent spring rotation drive portion 48 below this flange portion 46.

The first, second, third, and fourth radial cams 35, 36, 37, and 38 are each provided with a protrusion 35a and a recess 35b on their circumferences. The shapes of the first, second, third, and fourth radial cams 35, 36, 37, and 38, that is, the positions and shapes of the protrusions 35a and recesses 35b are determined by the encoded output of the rotary switch 1. Determined. For example, in the first radial cam 35, the protrusions 35a and the recesses 35b have the same width and are arranged alternately at approximately equal intervals, and in the third radial cam 37, the protrusions 35a and the recesses 35b
has a circular arc reaching 180°, and in the fourth radial cam 38, the protrusion 35a has a circular arc reaching 300°.

The detent spring rotation drive unit 48 has a pair of radial tongues 26 of the detent spring 25 in its grooved key.
In the fitted state, the detent spring 25 is rotated. As a result, the pair of convexly curved protrusions 50 on the lower surface side of the detent spring 25 are engaged with any one of the detent valleys 30 provided in the annular recess 24 of the base 3.

Since the detent spring 25 is formed to have elasticity so as to be bent in the direction of the upper and lower surfaces thereof, the first and second rotors 23a and 23b assembled to each other are aligned with the top plate 4 of the housing 2. , thereby pressing the upper surface of the first radial cam 35 of the first rotor 23a so as to come into close contact with the inner surface of the top plate 4. Therefore, the path from the circular hole 6 at the center of the top plate 4 to the inside of the housing 2 is blocked, preventing dust in the atmosphere from entering the inside of the rotary switch 1.

As shown in FIG. 5, in the movable electrical contact 34, one of the movable electrical contacts 34
b and one mechanical operation end 34d are connected to the terminal pin 3.
2, and the other movable electrical contact 34c and the other mechanical operating end 34e.
and are on the same side with respect to the terminal pin 32,
Movable electrical contacts 34b and 34c and terminal pin 3
The reliability of contact and separation operations with 1 and 33 is high.

Furthermore, since the rotary switch 1 has four movable electrical contact parts 34b and 34c that electrically open and close independently of the two terminal pins 32,
Can express binary coded decimal code.

[Brief explanation of drawings]

FIG. 1 is an exploded perspective view of the rotary switch according to the present invention, FIG. 2 is a perspective view as seen from the bottom of the housing, and FIG. 3A is a plan view of the rotary switch shown in FIG. Figure 3B is a sectional view taken along the line B-B in Figure 3A, Figure 4 is a diagram of the positional relationship between the code number, detent peaks and valleys, and terminal pins, and Figure 5 is the assembled state. FIG. 3 is a plan view of the first rotor, movable electrical contacts and terminal pins. 1...Rotary switch, 2...Housing, 3...
...Base, 4...Top plate, 6...Circular hole, 12...
Base hooking part, 13... Insertion guide slope, 14...
... Base mounting surface, 15 ... Base fixing vertical surface, 1
6...Base fixing slope, 20...Latching part, 23a
and 23b... a first rotor and a second rotor,
25...detent spring, 30...detent valley,
31, 32 and 33...terminal pin (fixed electrical contact), 34...movable electrical contact, 34a...
Coil parts, 34b and 34c...Movable electrical contact parts, 34d and 34e...Mechanical operating end, 40
...Manual rotation part.

Claims (1)

[Claims] 1. An insulating housing having a top plate with an opening formed therein, and an electrically insulating housing that is attached to the lower end of the housing in such a manner that relative displacement with the housing is prohibited and that closes the lower end of the housing. a base; a plurality of fixed electrical contacts fixed to and disposed through the base; mounted within the housing with an initial stress between the fixed electrical contacts; a movable electrical contact, and a rotary operating section disposed within the housing and protruding from the opening to the outside of the housing at the upper part thereof, and by rotating the rotary operating section, the movable electrical contact is disposed within the housing. a rotor that engages or disengages a contact to switch electrical connection between the fixed electrical contacts, the base having a plurality of valleys on opposing surfaces within the housing; A spring member is interposed between the bottom surface of the rotor and the trough, and the housing of the rotor is formed in a radial shape, and a spring member having a protrusion that engages with the trough is interposed between the bottom surface of the rotor and the trough. A rotary switch characterized in that an upper surface located inside contacts the inner surface of the top plate of the housing in a biased state surrounding the opening, and the corresponding contact surface functions as a sealing surface with respect to the opening. .