JPH0312176Y2 - - Google Patents

Description

[Detailed Description of the Invention] [Industrial Application Field] The present invention relates to a sealed rotary switch used for electrical control of automobiles, construction equipment, etc., which are used in harsh environments.

[Prior Art] Modern automobiles, construction equipment, and other industrial machinery and equipment are constantly moving from various departments that involve mechanical movement.
There are an increasing number of devices that perform electrical control by extracting electrical control signals.

Conventionally, microswitches have been mainly used for extracting control signals for such electrical control. This micro switch is
The operating force for turning the switch ON/OFF is extremely small.
Moreover, despite its small size, a snap spring and a lever mechanism are provided inside the switch in order to increase the operating contact pressure of the switch.

However, due to this small operating force, there is a problem in that reliability under extremely low temperatures is extremely reduced.

For example, in the case of a rotary switch B using a conventional micro switch A as shown in FIG.
Sufficient operating force is applied to the actuator E to prevent malfunctions due to freezing or the like.

However, when the pressing force of the actuator lever D is released and the actuator E returns due to the restoring force of the internal spring, the restoring force also exceeds the force resisting the operating force (minimum operating force) in the actuator E section. ), so if ice forms on the sliding parts of actuator E or the movable parts of the internal mechanism, actuator E
This will cause a malfunction that will cause the device to become stuck and be unable to recover. Moreover, even if it moves to return, a delayed operation occurs that is slower than the normal return speed, resulting in a timing shift with other control signals, resulting in a malfunction in the electrical control.

[Problems to be Solved] In view of the above-mentioned matters, the present invention has been developed to ensure reliable operation of the switch by interlocking with the operating mechanism even under harsh operating conditions. The purpose of this invention is to provide a rotary switch that is robust and can be mass-produced at low cost.

[Technical means for solving the problem] In the present invention, a bottomed inner wall is provided with an enlarged diameter step along the inner peripheral surface near the opening, and the peripheral surface and the bottom wall are integrally constructed. A case provided with a cavity, and at least one pair of electrodes in the case, in which a part of the electrode is exposed at an appropriate position on the wall of the lumen deeper than the enlarged diameter step part of the lumen, and electrical wiring connection is possible from the outside of the case. A disk-shaped seal comprising a fixed contact and a tongue piece in a central through-hole, the outer periphery of which is tightly fitted into the enlarged diameter stepped portion of the inner cavity in an airtight manner and immovable in the axial direction. a member, and a large diameter part that is linked to the member that rotates the rotary switch and loosely fits into the opening edge of the inner cavity, and has a protruding shaft that projects into the inner cavity in the axial direction from the center of the large diameter part. , a protruding shaft that comes into elastic contact with the tongue piece of the sealing member and passes through the sealing member in an airtight manner, and a retaining washer is fixed to the shaft on the shaft end side to prevent the sealing member and the protruding shaft from coming off, thereby protruding into the inner cavity. is rotatably engaged with the rotating member in the inner cavity closed by the sealing member, and is attached to the wall surface of the inner cavity. The above problem is solved by including a movable contact that can short-circuit between a pair of exposed electrodes as the rotating member rotates.

[Embodiment] FIGS. 1 to 3 show an embodiment of a sealed rotary switch according to the present invention, which will be described in detail below with reference to the drawings.

Reference numeral 1 denotes a bottomed case with a cylindrical inner cavity 1a, and a concave or convex bearing portion 2 is provided at the center of the bottom wall 1b of the inner cavity 1a of the case 1.

The bearing portion 2 in the embodiment is a concave bottomed hole 2a.

The case 1 is molded from a synthetic resin material so that each wall surface of the inner cavity 1a forms an integral structure that cannot be separated.
At the time of molding, the mounting ears 1c and 1d are molded.

When molding the case 1 with resin, an enlarged diameter stepped portion 1f parallel to the opening edge 1e of the inner cavity 1a is formed near the opening edge 1e, and a groove 1h along the inner circumferential surface 1g of the inner cavity 1a is formed. may be provided.

At this time, some electrodes 3a of the pair of fixed contacts 3,
Leave 3a exposed.

The other parts of the fixed contacts 3, 3 are led out from the inner cavity 1a to the outside of the case 1, and the pair of fixed contacts 3, 3 are inserted into the case so that they become terminals 3b, 3b for electrical wiring. Insert mold to 1.

A rotary member 4 is fitted into the opening edge 1e of the inner cavity 1a of the case 1 so as to cover the inner cavity 1a.

The rotating member 4 has a flat large diameter portion 4a that loosely fits into the opening edge 1e of the inner cavity 1a, and a tip 4d of a protruding shaft 4b that projects into the inner cavity 1a along the central axis of the large diameter portion 4a. , the protruding shaft 4 is supported in the bottomed hole 2a.
b is rotatable within the inner cavity 1a.

A groove 4e is provided at the base of the protruding shaft 4b, and the inner peripheral edge of the through hole passing through the center of the axis of the disk-shaped sealing member 5 made of a slightly elastic synthetic resin material is provided in the groove 4e. The tip 5c of the annular elastic tongue piece 5b provided on the tongue piece 5a is airtightly fitted.

The outer peripheral edge 5d of the sealing member 5 is formed by a groove 1h of an enlarged diameter stepped portion 1f provided near the opening edge 1e of the inner cavity 1a.
It is fitted airtightly and firmly enough that once it is fitted, it cannot be easily removed.

In the middle of the protruding shaft 4b of the rotating member 4, a sealing member 5 is sandwiched between the inner surface 4f of the large diameter portion 4a and the retaining washer 6, so that the rotating member 4 and the sealing member 5 are integrally coupled. Therefore, a fitting groove 4g into which the inner edge 6a of the locking washer 6 is fitted is provided, and the locking washer 6 is inserted into the fitting groove 4g.
is inserted and fitted from the shaft end side, and the washer 6 is fixed to the protruding shaft 4b.

The retaining washer 6 is molded from a synthetic resin material that has a small coefficient of friction with respect to the seal member 5 and has some elasticity.

In addition, as shown in FIGS. 1 and 2, the washer 6
is formed relatively thick, and this washer 6 is formed to have a relatively thick wall.
As shown in FIG. 2, the occupied area within the sealed inner cavity 1a becomes large, and there is also the effect of expelling excess air.

From groove 4g to 4d on protruding shaft 4b,
A rotation preventing notch 4h is provided on the side surface of the protruding shaft 4b to face each other, and a center hole 7a of the movable contact 7 is non-rotatably fitted into the root of the portion where the notch 4h is provided. .

The movable contact 7 is made of a conductive elastic material, and contact portions 7d, 7d are formed at the tips of elastic pieces 7c, 7c extending in an S-shape from the outer periphery of a base 7b provided with a center hole 7a. , the contact portions 7d, 7d are
As the rotating member 4 rotates, the bottom wall 1b of the case 1
It is designed to slide by pressing against the surface of the

The pair of fixed contacts 3, 3 have contact portions 7d,
At the rotating and sliding passages 7d, they are exposed facing each other around the bottomed hole 2a of the bearing 2, and when the contact portions 7d, 7d come into contact with the exposed electrode portions, both fixed contacts The movable contactor 7 short-circuits between 3 and 3 to perform a switch action.

In the rotary member 4 in the embodiment, an actuator arm 8 for connecting with an external mechanism that rotationally drives the rotary member 4 is simultaneously molded on the outside of the large diameter portion 4a when the rotary member 4 is molded with resin. ing.

This actuator arm 8 is a row of members for operating the rotary switch of the present invention, and is made separately from the large diameter part 4a of the rotating member 4, and is secured with screws or the like to the large diameter part 4a of the rotating member 4. It may be fixed to the portion 4a.

Further, on the outside of the large diameter portion 4a of the rotating member 4, a recess for connecting with an appropriate actuator member,
Alternatively, a protrusion or the like may be provided.

On the other hand, the sealed inner cavity 1a of the fixed contacts 3, 3
The exposed electrodes 3a, 3a inside the bottom wall 1
The peripheral surface 1i is not limited to the surface of the inner cavity 1a.
It may be. In this case, the contact portions 7d, 7d of the elastic pieces 7c, 7c in the movable contactor 7,
What is necessary is just to make it slide on the said peripheral surface 1i.

Furthermore, the exposed electrodes 3 of the fixed contacts 3, 3
a, 3a may be flush with the bottom wall 1b or the surface of the peripheral surface 1i, or may slightly protrude from the surface. In that case, depending on the exposed state of the electrodes 3a, 3a, the contact portions 7d,
7d is the exposed electrode 3 with appropriate contact pressure.
a, 3a.

The rotary switch described above includes a resin-molded case 1, a rotating member 4, a seal member 5, a retaining washer 6, and a pressed movable contact 7.
It is formed by assembling as follows.

First, the sealing member 5 is attached to the base of the protruding shaft 4b of the rotating member 4 using a driving device or the like by utilizing the elastic diameter expanding action of the elastic annular tongue piece 5b.

Next, the retaining washer 6 is similarly fitted into the groove 4g in the middle of the protruding shaft using a driving device or the like using the elastic diameter expanding action.

Furthermore, the movable contact 7 is fitted into the base of the portion of the protruding shaft where the notch 4h is provided.

Even if the fit between the movable contact 7 and the protruding shaft 4b is loose enough to easily fall off, it will not affect the function of the rotary switch. It is more convenient to do so.

In addition, the fitting between the movable contact 7 and the protruding shaft 4b is positively strengthened, and in particular, an elastic check piece having a check function is provided on the periphery of the fitting hole 7a of the movable contact 7,
When the movable contact 7 is prevented from coming off, the movable contact 7 can also serve as the retaining washer 6.

After fitting all the related parts onto the protruding shaft 4b of the rotating member 4, the rotating member 4 is attached to the case 1.

In this case, the outer circumferential diameter of the sealing member 5 is larger than the diameter of the opening edge 1e of the inner cavity 1a of the case 1, but the outer circumferential edge 5d of the sealing member 5 has a slight taper portion 5e. and a seal member 5
is used as an elastic material, so the case 1 and the rotating member 4
By aligning the axes of the rotating member 4 with the case 1, the sealing member 5 is attached to the case 1.
is fitted into the groove 1h.

When installing the rotating member 4 in the case 1, it is necessary to align the axis of the inner cavity 1a with the axis of the rotating member 4. By providing a hole on the distal end side of the protruding shaft 4b, which fits into the convex shaft of the bearing portion 2, alignment of the axes can be facilitated.

Also, when press-fitting the disc-shaped seal member 5,
The large diameter portion 4a, which is slightly smaller in diameter than the seal member 5, acts as a push-in die that presses the seal member 5, and after the rotating member 4 is attached to the case 1, it fits into the opening edge 1e of the case 1. , protruding shaft 4b
Together with one pivot at the tip 4d, the other pivot for the case 1 is formed.

The large diameter portion 4a does not necessarily need to be in contact with the opening edge 1e, and the diameter of the large diameter portion 4a may be considerably smaller than the diameter of the opening edge 1e.

However, as shown in the embodiment, when the large diameter portion 4a is fitted into the opening edge 1e, both ends of the rotating member 4 in the axial direction are pivoted at two points as described above.
The structure is strong against forces tilting in the axial direction.

Further, the disc-shaped sealing member 5 is firmly fixed to the rotating member 4, and the sealing member 5 can be easily inserted into the enlarged diameter stepped portion 1f of the inner cavity 1a of the case 1. , serves to cover the inner cavity 1a in an airtight manner, and also firmly connects the case 1 and the rotating member 4.

FIG. 4 shows an example of the usage state of the rotary switch according to the present invention, in which the connecting pin 8a provided at the tip of the actuator arm 8 is engaged with the groove 20a of the cam 20.

In this case, when the rotary switch is driven in either the ON or OFF direction, sufficient operating force is transmitted to the rotating member 4 to ensure reliable operation.

FIG. 5 shows the switching angle at which the movable contact 7 short-circuits the fixed contacts 3, 3 during one rotation of the rotating member 4, and this switching angle is:
It is determined by the length of the exposed portion of the fixed contacts 3,3. In the embodiment shown in FIG. 3, as shown in FIG. 5, ON-OFF is performed every 90 seconds.

[Effects] As described above, according to the present invention, by simply fitting the disc-shaped seal member firmly connected to the rotating member into the enlarged diameter stepped portion of the case, the seal member can move unevenly in the axial direction. The disc-shaped sealing member is fixed to the case to connect the case and the rotating member, and the disc-shaped sealing member is fixed to the opening edge of the inner cavity that houses the electrical contact to keep the inner cavity in an airtight state. There is no risk of condensation or icing forming on the electrical contacts housed in the internal cavity.

The rotating member connected to the operation drive unit is directly connected to the movable contact, so if a sufficiently large operating force is applied, the switch may become inoperable due to freezing due to moisture contained in the sealed part. There will be no malfunction.

Further, the rotary switch according to the present invention has a simple structure, the main parts can be made by resin molding, and the number of parts is small, making it easy to assemble and automatically assemble.

Because of this, we can provide rotary switches that follow the drive mechanism and reliably output electrical signals even in harsh operating environments, are structurally robust, and are inexpensive. .

[Brief explanation of drawings]

FIG. 1 is an exploded perspective view of an embodiment of the rotary switch of the present invention, FIG. 2 is a central vertical cross-sectional view of the same rotary switch, and FIG.
4 is a plan view showing the rotary switch in use, FIG. 5 is a plan view showing the switching angle of the rotary switch, and FIG.
The figure is a front view of a cam device showing a rotary switch using a conventional micro switch. 1...Case, 1a...Inner cavity, 1b...Bottom wall, 1c,
1d... Mounting ear piece, 1e... Opening edge, 1f... Expanded diameter step, 1g... Inner peripheral surface, 1i... Circumferential surface, 1h... Groove, 2...
Bearing, 2a...bottomed hole, 3...fixed contact, 3a...electrode, 3b...terminal, 4...rotating member, 4a...large diameter part,
4b...protruding shaft, 4d...tip, 4f...inner surface, 4g...
Groove, 4e... Groove, 4h... Notch, 5... Seal member, 5
a...Inner peripheral edge, 5b...Elastic tongue piece, 5c...Tip, 5d
...outer peripheral edge, 6...retention washer, 6a...inner mouth edge, 7...movable contact, 7a...center hole, 7b...base, 7c, 7c...elastic piece, 7d, 7d...contact part,
8... Actuator arm, 8a... Connection pin, 2
0...Cam, 20a...Groove.

Claims (1)

[Claims for Utility Model Registration] An enlarged diameter stepped portion is provided along the inner peripheral surface near the opening,
and a case having a bottomed inner cavity in which the circumferential surface and the bottom wall are integrally constructed, and a part of the electrode is exposed at an appropriate position on the inner cavity wall deeper than the enlarged diameter step of the inner cavity in the case, and At least one device that allows electrical wiring connections from outside the case.
a pair of fixed contacts; and a disk-shaped member having a tongue piece in the central through-hole, the outer periphery of which is tightly fitted into the enlarged-diameter stepped portion of the inner cavity in an airtight manner and immovable in the axial direction. a sealing member, a large diameter portion that is connected to a member that rotates the rotary switch and loosely fits into the opening edge of the inner cavity, and a protrusion that projects into the inner cavity in the axial direction from the center of the large diameter portion. The shaft elastically contacts the tongue piece of the sealing member and passes through the tongue piece in an airtight manner, and a retaining washer is fixed to the shaft on the shaft end side to prevent the sealing member and the protruding shaft from coming off,
A protruding shaft that projects into the inner cavity is rotatably engaged with a rotating member that is rotatable within the inner cavity, and is non-rotatably engaged with the rotating member within the inner cavity that is closed by the sealing member. and a movable contact capable of short-circuiting a pair of electrodes exposed on the wall surface of the inner cavity as the rotating member rotates.