JPH1012094A - Rotary switch - Google Patents

Abstract

PROBLEM TO BE SOLVED: To increase a contact pressure and prevent chattering compared with a rotary switch entering a connection state during pressure release of a movable terminal by applying a contact pressure of a contact in a connection state by means of rotary movement. SOLUTION: A movable terminal 30 enters a slack free state by each protrusion 53 of a holding piece 50 engaging with a recess portion 23 when the recess portion 23 of a cam 20 is opposed to the movable terminal 30. When a contact 33 mounted at a tip end of the movable terminal 30 in this situation is released from a contact 43 mounted at a tip end of a fixed terminal 40 on a outside thereof, and connection between the movable terminal 30 and the fixed terminal 40 is released. From this situation the cam 20 is rotated, the holding pieces 50 on both ends are pressed outward, the movable terminal 30 is slackened outward, and a connection state between the movable terminal 30 and the fixed terminal 40 is entered. A contact pressure of contacts 33 and 43 in this connection state depends upon rotary movement of the cam 20, therefore, that contact pressure can be significantly increased compared with the rotary switch entering the connection state during pressure release of the movable terminal, and chattering can be prevented effectively.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a rotary switch, and more particularly, to a rotary switch used for turning on / off a switchgear arranged in the middle of a transmission line. To a rotary switch for an auxiliary switch.

[0002]

2. Description of the Related Art A switching device of this type is provided with an auxiliary switch for turning on and off the switching device. As this auxiliary switching device, a rotary switch of a rotary cam type has been frequently used. 7 and 8 show a conventional example of such a rotary switch.

First, the rotary switch shown in FIG.
A cam 2 rotatably supported in a case 1, and a pair of movable terminals 3A and 3B operated by the rotation of the cam 2.
And two sets of fixed terminals 6A, 6A, 6B, 6B that are connected and disconnected synchronously by operating the movable terminals 3A, 3B.

The cam 2 has cam surfaces 2a, 2a formed of arc-shaped convex portions at symmetrical positions on the outer peripheral surface, and the cam surfaces 2a, 2a
There are concave portions 2b, 2b between them. The movable terminals 3A and 3B are symmetrically arranged on the outer peripheral side of the cam 2, that is, above and below the cam 2. Each of the movable terminals 3A and 3B is urged by the coil springs 4 and 4 in a direction approaching the cam 2, and has an operation element 5 at the center.

[0005] Two sets of fixed terminals 6A, 6A, 6B, 6B
Are inside the movable terminals 3A, 3B,
Parallel to 3B. One set of fixed terminals 6A, 6A
Inserted into the case 1 from both left and right sides of the case 1, each end portion (contact point) opposes both ends (contact points) of one movable terminal 3 </ b> A from inside. The other set of fixed terminals 6B, 6B is also inserted into the case 1 from both left and right sides of the case 1, and each end faces the both ends of the other movable terminal 3B from inside.

FIG. 7 shows a connection state. In this state, the respective tips of the operators 5, 5 are fitted into the recesses 2 b, 2 b of the cam 2. Therefore, both the contacts of the movable terminal 3A are pressed against the contacts of the fixed terminals 6A, 6A from outside by the urging forces of the coil springs 4, 4, and the fixed terminals 6A, 6A are connected. At this time, both contacts of the movable terminal 3B are simultaneously
The fixed terminals 6B, 6B are actuated by the urging forces of the coil springs 4, 4.
Of the fixed terminals 6B and 6
A connection state is also established between B.

When the cam 2 is rotated from this state, the operators 5, 5 ride on the cam surfaces 2a, 2a of the cam 2, whereby the operators 5, 5 move outwardly against the urging force of the coil springs 4, 4. Is pressed. Accordingly, the movable terminals 3A, 3B
Also move outward, so that the contacts are separated and the fixed terminals 6A, 6A
The connection between the terminals A and between the fixed terminals 6B, 6B is in a disconnected state. The fixed terminals 6A, 6A, 6B, 6B are connected to an input cable and an output cable, respectively, which are connected to the switching circuit breaker.

The rotary switch shown in FIG.
The pair of movable terminals 3A, 3A are constituted by leaf springs. FIG. 8 shows a connection state, in which the movable terminals 3A, 3A are connected to the fixed terminals 6A, 6B by the urging forces from the coil springs 4, 4. When the cam 2 is rotated from this state, the cam surface 2a moves against the movable terminals 3 against the urging force of the coil springs 4 and 4.
The distal ends of A and 3B are deflected outward, and the contacts are in a disconnected state. Note that members corresponding to those in FIG. 7 are denoted by the same reference numerals, and detailed description thereof will be omitted.

[0009]

However, in the rotary switch shown in FIG. 7, since the coil springs 4, 4 are almost fully extended in the connected state, the fixed terminals 6A, 6A, 6B of the movable terminals 3A, 3B are connected. , 6B, that is, the contact pressure is small.

[0010] Here, a large impact is generated during the ON / OFF state of the switching circuit breaker, that is, during operation, and this impact also reaches the rotary switch constituting the auxiliary switching device. And
Since the contact pressure of the rotary switch is small, a phenomenon called chattering in which the contact repeatedly turns on and off is apt to occur, and it becomes difficult to accurately perform an on / off operation of the on / off circuit breaker. In addition, this may cause a reduction in the life of the contact, and hence the life of the rotary switch.

Further, the coil springs 4, 4 in the disconnected state are provided.
Since the amount of contraction from the natural length of the coil springs 4 is small, the restoring force of the coil springs 4 when transferring from the disconnected state to the connected state is small. Therefore, there is also a problem that responsiveness is poor.

As described above, the rotary switch shown in FIG. 7 has a structure in which the method of applying the force of the coil spring 4 to the movable terminals 3A and 3B is apt to cause a mechanical loss, so that the above-described problem occurs. .

Similarly, in the rotary switch shown in FIG. 8, since the coil spring 4 is almost fully extended in the connected state, the contact pressure of the contact is small.

Here, in order to increase the contact pressure, the spring strength of the coil spring 4 may be increased.
Since a large load is applied to the rotating shaft that rotates the, the external operating force must be increased, which has the disadvantage of increasing the size of the device configuration. As a result, since the contact pressure of the coil spring 4 has to be reduced, chattering is likely to occur similarly to the rotary switch shown in FIG. 7, and it becomes difficult to accurately perform an on / off operation for the on / off circuit breaker. In addition, there is also a problem that the life of the contact, and eventually the rotary switch, is easily damaged.

The present invention has been made in order to solve such problems of the prior art. The movable terminal can be pressed against the fixed terminal with a maximum pressing force, and the movable terminal is connected from the connected state. The elastic body that shifts to the release state can move the movable terminal with the maximum force, and as a result, chattering can be reliably prevented, the reliability as an on / off switch can be improved, and its life and response are improved It is intended to provide a rotary switch that can be used.

Another object of the present invention is to provide a rotary switch capable of effectively protecting a movable terminal.

Another object of the present invention is to reliably prevent harmful gases such as flux for soldering from adhering to the contacts to cause conduction failure, and in this respect also to improve reliability. It is to provide a rotary switch.

[0018]

A rotary switch according to the present invention is provided with a rotatably supported cam and a cam sandwiched between the cams. A pair of movable terminals that are elastically displaced in a direction away from each other, and are located outside the pair of movable terminals and at positions where the distal end portions of the pair of movable terminals in a state of being elastically displaced by being pressed by the cam are in pressure contact. And a pair of fixed terminals, whereby the above object is achieved.

Preferably, the pair of movable terminals are fixed at an intermediate portion, and the distal end side is bent and deformed in a direction away from the center axis of the cam by a pressure accompanying the rotating operation of the cam, and each of the distal end portions is deformed. This is a leaf spring that presses against a pair of fixed terminals.

Preferably, a return elastic member is provided outside each of the pair of movable terminals, and when the distal ends of the pair of movable terminals return to the center axis side of the cam, the elastic members are provided. Is configured to press the pair of movable terminals with the maximum force.

Preferably, the cam, the pair of movable terminals, and the fixed terminal are all housed in a case, and base ends of the movable terminal and the fixed terminal pass through slits formed in the case. Each of the movable terminals protrudes outside the case, and a deformation absorbing portion curved in an arc shape is formed between the intermediate fixed portion and the distal end portion of the movable terminal.

Preferably, a shielding chamber for preventing harmful gas containing an insulating material from entering the case is formed at a portion connected to the slit formed in the case.

The operation will be described below.

According to the above configuration, in the connection state of the contacts, the tip of the movable terminal is in a state of being pressed against the fixed terminal. That is, since the contacts are in the connected state during the pressurizing operation of pressing the movable terminal, the contact pressure of the contacts in the connected state is markedly lower than that of the conventional rotary switch in which the contacts are connected when the movable terminal is released from the pressure. Can be larger. Therefore, even when the impact during the operation of the switching circuit breaker is applied,
Since the distal end of the movable terminal is firmly in close contact with the fixed terminal, chattering does not occur.

Further, according to the configuration in which the elastic body presses the pair of movable terminals with the maximum force when releasing the connection state of the contacts and returns the pair to the disconnection position, the return operation can be promptly performed accordingly. Responsiveness can be improved.

According to the structure in which the movable terminal is provided with the deformation absorbing portion as described above, when the movable terminal bends outward,
There is a tendency for the bending load to be concentrated on the portion directly above the fixing portion. When such a concentrated load acts on a specific portion, this portion may deteriorate with time and may be damaged. However, since the deformation absorbing portion is provided immediately above the fixed portion, the deformation absorbing portion has a function of dispersing the load.
Therefore, deterioration of this portion over time is suppressed, and stable restoring force is maintained for a long period of time. Therefore, the life of the rotary switch can be improved and its reliability can be maintained for a long time.

According to the structure in which the shielding chamber for preventing intrusion of the harmful gas containing the insulating material is formed in the portion connected to the slit formed in the case, the contact is contaminated by the harmful gas. Since there is no contact, it is possible to prevent conduction failure of the contacts.

More specifically, in a rotary switch used as an auxiliary switch, a printed circuit board is generally connected to a base end of a movable terminal and a fixed terminal. When soldering, there is a possibility that the vapor of the flux enters the case and adheres to a portion serving as a contact between the movable terminal and the fixed terminal. If the flux adheres to the contact, the flux is an insulating material, so even if the tip of the movable terminal is pressed against the fixed terminal, a conduction failure occurs.

However, according to the above configuration, the flux as a harmful gas does not enter the case, so that the flux does not adhere to and accumulate on the contact over time. Therefore, it is possible to reliably prevent the conduction failure of the contacts,
The reliability of the rotary switch can be maintained for a long time.

[0030]

DESCRIPTION OF THE PREFERRED EMBODIMENTS Embodiments of the present invention will be specifically described below with reference to the drawings.

(Embodiment) FIGS. 1 to 6 show an embodiment of the rotary switch of the present invention. In the present embodiment, this rotary switch is used as a rotary switch for an auxiliary switch that turns on and off a switching breaker provided in the middle of a transmission line.

FIG. 1 shows an auxiliary switch. This auxiliary switch is configured by combining a plurality of rotary switches A, A,... In the thickness direction. Each rotary switch A
Are connected together with the end plates C, C and the clicker D by through bolts E, E on the printed circuit board B, and are operated synchronously by rotating the operating shaft F, which penetrates them, with the handle G. The cross section of the shaft F is square. The clicker D incorporates a well-known click mechanism that elastically fixes the shaft F at predetermined angles.

Each rotary switch A is shown in FIGS.
As shown in FIG. 3, a case 10 in the shape of a rectangular box having a front surface opened and having a relatively small depth (thickness), a cam 20 rotatably supported at the center of the case 10, and a cam 20 located on both sides of the cam 20. A pair of movable terminals 3 supported vertically in the case 10
0, 30 and a pair of fixed terminals 40, which are located outside the movable terminals 30, 30 and are vertically supported in the case 10.
40, a pair of holding pieces 50, 50 respectively mounted on the movable terminals 30, 30, and a coil spring.
A pair of return elastic members 6 arranged outside each of 0 and 50
0,60.

The details of each section will be described below. First, the case 10 will be described. As shown in FIGS. 4 to 6, the case 10 has round holes 11, 11 at the upper and lower portions through which the through bolts E pass. A cam 20 is provided on the rear surface of the case 10.
Are provided, and a pair of round holes 16b, 16b on both sides where the holding pieces 50, 50 are fitted are provided. Immediately below the round hole 16a, a receiving portion 17 that temporarily supports the cam 20 when the shaft F is passed is protruded. Further, in order to hold the fixed terminal 40, upper and lower two-stage projections 18 and 19 are provided so as to protrude inside the side wall portion. Lower projection 1
Reference numeral 9 also serves as a support for the elastic body 60, and a concave portion 19a into which the elastic body 60 is fitted is provided on the inclined inner surface.

On the bottom surface of the case 10, upper and lower slits 12, 12 into which the movable terminals 30 are fitted are provided on both sides of the lower round hole 11. A wide space (chamber) 13 is provided between the slits 12. On these left and right outer sides, upper and lower two-stage slits 14, 14 into which the fixed terminals 40 are fitted are provided, and a wide space (chamber) 15 is located between the slits 14, 14.
Is provided.

The cam 20 is rotatably fitted in a round hole 16a formed in the center of the rear surface of the case 10, and has a square hole 21 through which the shaft F passes at the center. A pair of fan-shaped convex portions (cam surfaces) 22, 22 are provided symmetrically on the outer peripheral surface of the cam 20, and a pair of concave portions 2 are provided between the convex portions 22, 22.
3, 23 are formed.

As shown particularly in FIG. 2, the movable terminal 30 located outside the cam 20 is made of a leaf spring, and has a deformation absorbing portion 31 formed in an intermediate portion and curved in an arc shape. Below the deformation absorbing portion 31, there is a bent portion 32 which protrudes in a rectangular shape to the left and right inside. A contact 33 made of a screw is attached to the upper end of the movable terminal 30 so as to face outward.

The movable terminal 30 is formed on the case 10 by fitting the bent portion 32 into the inner space 13 formed at the lower portion of the case 10 and fitting the upper and lower portions of the bent portion 32 into the slits 12, 12. Fixed. The portion of the movable terminal 30 fixed to the case 10 above the deformation absorbing portion 31, that is, the tip side can freely bend to the left and right sides. The lower end of the movable terminal 30 projects below the case 10 as an input (or output) lead.

Fixed terminal 4 located outside movable terminal 30
In the case 0, the upper and lower portions are bent, the upper and middle portions are held by upper and lower protrusions 18 and 19, and the vicinity of the lower bent portion is fitted into the slits 14 and 14 and the space 15, so that the case 10 are fixed along the side surface. A contact 43 made of a screw is attached to the upper end of the fixed terminal 40, and the lower end protrudes below the case 10 as an output (or input) lead.

The holding piece 50 attached to the movable terminal 30 is
The lower end is fitted into a round hole 16b provided on the rear surface of the case 10, so that the case 10 is rotatably supported in the case 10. On the rear surface of the holding piece 50, a slit 51 into which the movable terminal 30 is fitted is provided. On the outer surface of the holding piece 50, a projection 52 is provided for fixing the elastic body 60,
A protrusion 53 is provided on the inner surface to abut the outer peripheral surface of the cam 20. The deformation absorbing portion 31 of the movable terminal 30 is exposed inside the lower end of the holding piece 50 so as not to hinder the deformation.

The return elastic body 60 disposed outside the holding piece 50 is formed of a coil spring whose winding diameter changes in the axial direction. The elastic body 60 has a large-diameter end fitted into a concave portion 19a formed on the inner surface of the projection 19, and a projection 5 fitted into the small-diameter end.
By being inserted, 2 is supported in a compressed state between the holding piece 50 and the projection 19.

Next, the method of use and functions of the rotary switch A will be described.

The movable terminals 30, 30 and the fixed terminals 40, 4
Since all the lower ends of the protrusions 0 protrude below the case 10, they can be directly soldered to the printed circuit board B. That is, the lower ends of the movable terminal 30 and the fixed terminal 40 are an input terminal and an output terminal. Further, the fixed terminals 40, 40 are connected to an on / off operation section of the switching circuit breaker via a cable (not shown). Further, the circuit on the printed circuit board B is connected to the computer of the master station. When the switching circuit breaker is turned on / off via the rotary switch A, the state is reported to the computer of the master station. I have.

In the soldering process, flux vapor is generated. This vapor tends to enter the case 10 through a slit 12 or the like provided on the bottom surface of the case 10 so as to protrude each terminal downward.

However, here, a space 13 is formed between the upper and lower slits 12 and 12 into which the movable terminal 30 fits, and a space 15 is formed between the upper and lower slits 14 and 14 into which the fixed terminal 40 fits. Therefore, the vapor accumulates in the spaces 13 and 14 and agglomerates and adheres to the inner surfaces thereof, so that the vapor does not enter the case 10. Therefore, the steam is discharged from the contact 3 in the case 10.
Insufficient conduction due to adhesion to 3, 43 is prevented.

The movable terminals 30 and 30 are
When the projections 53 of the holding pieces 50 are fitted into the recesses 23 when the movable terminals 30 face the movable terminals 30, there is no bending. In this state, the contacts 33 attached to the tip of each movable terminal 30
Move away from the contact 43 attached to the distal end of the fixed terminal 40 on the outside, so that the movable terminal 30 and the fixed terminal 40
During this period, the connection is released. This is the state shown in the right half of FIG.

In this state, the shaft F is operated and the cam 2
When 0 is rotated, the holding portions 50, 50 on both sides are pressed outward by the convex portions 22, 22, of the cam 20, whereby the movable terminals 30, 30 are bent outward. As a result, the contact 33 attached to the tip of the movable terminal 30 becomes the contact 43 attached to the tip of the fixed terminal 40 on the outside.
And the movable terminal 30 and the fixed terminal 40 are connected. This is the state shown in the left half of FIG.

Since the contact pressure of the contacts 33 and 43 in the connected state depends on the pressurization accompanying the rotation of the cam 20, the contact pressure is higher than that of the conventional rotary switch which is connected when the movable terminal 30 is released from the pressurized state. The contact pressure can be significantly increased. Therefore, chattering is effectively prevented.

The lower part of the movable terminal 30 is the case 10.
Because of the fact that it is fixed to the bottom of the fixing part, there is a tendency for the bending load to be concentrated on the part immediately above the fixing part when flexing left and right outward. When such concentrated load acts on a specific part,
This part may deteriorate over time, leading to breakage.
However, in the present invention, since the deformation absorbing portion 31 is provided immediately above the fixing portion, the deformation absorbing portion 31 has a function of dispersing the load. Therefore, deterioration of this portion over time is suppressed, and stable restoring force is maintained for a long period of time. Therefore, the life of the rotary switch A can be improved,
And its reliability can be maintained for a long time.

The movable terminal 30 is pressed by the cam 20 and
Is bent outward, the elastic body 60 is compressed. This compression is maximum when the contacts 33 and 43 are pressed against each other. Therefore, when the pressing by the cam 20 is released, the movable terminal 30 quickly separates from the fixed terminal 40. Therefore, the operation when the contacts 33 and 34 are separated is assured, and the operation speed is increased. That is, responsiveness can be improved.

Further, in the above embodiment, the movable terminal 3
Since the 0 and the lower end of the fixed terminal 40 also serve as input / output terminals, no lead wire is required. Therefore, the number of parts can be reduced correspondingly, which is advantageous for cost reduction.

(Other Embodiments) The embodiments of the present invention are not limited to the illustrated examples, and various modifications are possible. For example, instead of the elastic body 60, a rubber or other shape spring can be used.

[0053]

According to the rotary switch of the present invention described above, the contacts are connected during the pressurizing operation of pressing the movable terminal, so that the contacts are connected when the movable terminal is released. The contact pressure in the connected state can be significantly improved. Therefore, even when an impact occurs during the operation of the switchgear, chattering does not occur because the tip of the movable terminal is firmly in close contact with the fixed terminal. Therefore, for example, when it is used as an auxiliary switch for an on / off operation with respect to an on / off circuit breaker, there is an advantage that the on / off operation can be performed accurately, and the life of the contact point and eventually the rotary switch can be improved.

According to the rotary switch of the third aspect, when the connection state of the contacts is released, the elastic body returns the movable terminal to the disconnection position with the maximum force, so that the responsiveness is improved. There is an advantage that can be improved.

According to the rotary switch of the fourth aspect, the deformation absorbing portion is provided between the fixed portion and the tip portion, and the deformation absorbing portion has a function of dispersing the load. Over time, and a stable restoring force is maintained for a long time. Therefore, also in this respect, there is an advantage that the life of the rotary switch can be improved and its reliability can be maintained for a long time.

According to the rotary switch of the present invention, the contact is not contaminated by the harmful gas, and the conduction failure of the contact can be prevented. Therefore, the reliability of the rotary switch is maintained for a long period of time. There are advantages that can be done.

[Brief description of the drawings]

FIG. 1 is a perspective view of an auxiliary switch showing an example of use of a rotary switch according to the present invention.

FIG. 2 is an exploded perspective view showing a structure of a rotary switch used in the auxiliary switch shown in FIG.

FIG. 3 is a front view of a rotary switch.

FIG. 4 is a perspective view of a case of a rotary switch.

FIG. 5 is a cross-sectional view taken along line AA of FIG. 3, showing only a case.

FIG. 6 is a sectional view taken along line BB in FIG. 3;

FIG. 7 is a front view schematically showing the structure of a conventional rotary switch.

FIG. 8 is a front view schematically showing the structure of another conventional rotary switch.

[Explanation of symbols]

 Reference Signs List A Rotary switch B Printed circuit board 10 Case 12, 14 Slit 13, 15 Space 20 Rotating cam 22 Convex part 23 Concave part 30 Movable terminal 31 Deformation absorption part 33 Contact 40 Fixed terminal 43 Contact 50 Holding piece 60 Elastic body for return

Claims (5)

[Claims] A cam rotatably supported, and a pair of movable terminals provided sandwiching the cam and elastically displaced in a direction away from a rotation center axis of the cam by a pressing force caused by a rotating operation of the cam. A rotary switch including a pair of fixed terminals disposed outside the pair of movable terminals and at positions where the distal ends of the pair of movable terminals are elastically displaced by being pressed by the cam; . 2. The pair of movable terminals are fixed at an intermediate portion, and the distal end side is bent and deformed in a direction away from the center axis of the cam by a pressing force caused by a rotation operation of the cam, and each of the distal end portions is deformed. 2. The rotary switch according to claim 1, wherein said rotary switch is a leaf spring pressed against said fixed terminal. 3. An elastic body for return is provided outside each of the pair of movable terminals, and when the distal ends of the pair of movable terminals return to the center axis side of the cam, the elastic body has a maximum value. 3. The rotary switch according to claim 1, wherein the pair of movable terminals are pressed by a force. 4. The case, wherein the cam, the pair of movable terminals, and the fixed terminal are all housed in a case, and base ends of the movable terminal and the fixed terminal pass through a slit formed in the case, and are outside the case. 3. The rotary switch according to claim 2, wherein each of said movable terminals has an arc-shaped deformation absorbing portion formed between said intermediate fixed portion and said distal end portion of said movable terminal. 5. A shielding chamber for preventing a harmful gas containing an insulating material from entering the case at a portion connected to the slit formed in the case.
The rotary switch as described.