JPH0372861B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION (a) Technical Field The present invention relates to an inhibitor switch for an automatic transmission.

(b) Prior Art An inhibitor switch for an automatic transmission is a switch that works in conjunction with a select lever on the driver's seat to turn on a predetermined contact point depending on the select position. In an inhibitor switch for an automatic transmission that rotates a movable element, a movable contact is provided on the movable element, and a fixed contact is provided on a substantially fan-shaped fixed plate. Fixed contacts are provided, for example, at P, R, N, D, and range positions. The P and N fixed contacts are used to conduct the engine starter circuit. The R range fixed contact is also used as a reverse light switch. D, and the range fixed contact are also used for engine control and the like. The fixed contacts on the fixed plate side are arranged at the same radial position from the center of rotation of the movable element (for example, as shown in Japanese Patent Laid-Open No. 47-40625). However, in conventional automatic transmission inhibitor switches, it has not been possible to reduce the size of the switch in order to ensure conduction range accuracy at the P and N positions. Continuity range accuracy at the P and N positions is extremely important from a safety standpoint. In other words, when the select lever is in the D or R position, if the conduction range of the inhibitor switch is inaccurate and the contacts in the P and N positions become conductive due to linkage play, installation error, etc., the moment the engine starts, the vehicle This is because the vehicle will be running. For this reason, the fixed contacts at the P and N positions are placed as far away from the center of rotation as possible, and the other fixed contacts are also placed in the same position accordingly, making it impossible to downsize the inhibitor switch. .

Further, in the conventional inhibitor switch, the same movable contact is used for all the fixed contacts, so there is a problem in that poor conduction is likely to occur.
That is, since the fixed contacts at the P and N positions are connected to the starter circuit, a large current flows, sparks are generated when the contacts are turned on and off, and a film is likely to form on the contact surfaces. When a film forms on the contact surface, the electrical resistance of the contact increases. On the other hand, since the contacts other than P and N are simply for lamp lighting and computer signals, only a small current flows through them. If the electrical resistance of the movable contact increases due to the coating, poor conductivity is likely to occur because only a small current flows through contacts other than P and N.

(c) Purpose of the Invention The purpose of the present invention is to miniaturize the inhibitor switch while maintaining the accuracy of the conduction range of the contacts at the P and N positions. Another object of the present invention is to obtain an inhibitor switch that does not cause conduction failure.

(d) Structure of the Invention The inhibitor switch for an automatic transmission according to the first invention includes a plurality of movable contacts 30 and 32 arranged at different radial positions from the center of rotation inside a substantially fan-shaped casing 10. A rotatable movable element 28, and P positions 14a, 14b, and N positions arranged at predetermined radial positions from the movable element rotation center position so as to be electrically connected through one of the movable contacts when the movable element rotates. 18a, 18b, and fixed contacts 16a for select positions other than P and N.
16b, 20a, 20b, 22a, 22b, 24
a, 24b, and the fixed contacts at the P and N positions are arranged on the largest radius position, and the fixed contacts for select positions other than the above P and N are smaller than the fixed contacts at the P and N positions. One of the fixed contacts 24a and 24b for select positions other than P and N is arranged at least at one end in the circumferential direction of the entire fixed contact arrangement, and the movable Among the movable contacts provided in the above, the movable contacts 32 corresponding to the fixed contacts for select positions other than the above P and N arranged at one end in the circumferential direction are movable contacts corresponding to the fixed contacts at the P position and the N position. 30 and offset to the one end side,
A notch 28a is provided at a radially outward position of a movable contact corresponding to a fixed contact for select positions other than P and N arranged at one circumferential end of the movable element, and a cutout 28a is provided in a substantially fan-shaped casing. It is characterized in that a notch 10a is provided on the radially outer side of the fixed contact disposed at one end in the circumferential direction.

Further, the second invention of the present application provides a plurality of movable contacts 30 disposed inside the substantially fan-shaped casing 10 at mutually different radial positions from the rotation center position.
32, and P positions 14a, 14b arranged at a predetermined radial position from the center of rotation of the movable element so as to be electrically connected through one of the movable contacts when the movable element rotates. , N position 1
8a, 18b, and fixed contacts 16a, 16b, 20a, 20b, 2 for select positions other than P and N
2a, 22b, 24a, and 24b, and the fixed contacts at the P and N positions are arranged on the same radial position, and the fixed contacts for select positions other than the above P and N are the fixed contacts at the P and N positions. Among the movable contacts arranged on a different radius position from the movable element, the movable contact 30 corresponds to the fixed contacts at the P position and N position, and the fixed contact for the select position other than the above P and N. The movable contacts 32 are arranged at different radial positions similarly to the fixed contacts.

Note that the reference numerals in parentheses indicate corresponding members in the embodiments described later.

(E) Embodiments Hereinafter, embodiments of the present invention will be described with reference to Nos. 1 and 2 of the attached drawings.
This will be explained based on the diagram.

An embodiment of the invention is shown in FIGS. 1 and 2. A substantially fan-shaped casing 1 having a notch 10a on one end side
An electrode plate 12 is fixed to the inside of 0 with screws (not shown). The pole plate 12 has fixed contacts 14a, 14b for the P position and fixed contacts 16a, 16a for the R position.
6b, fixed contacts for N position 18a, 18b, fixed contacts for D position 20a, 20b, fixed contact for position 2
2a, 22b, and position fixed contacts 24a, 2
4b is provided. Each fixed contact has a pole plate 12
It is fixed in a through hole provided in the. Also,
Each fixed contact point is located at the rotation center O of the shaft 26, which will be described later.
They are distributed at predetermined angles in the circumferential direction with . The shaft 26 is rotatably supported by the casing 10, and a movable element 28 is attached to a portion of the shaft 26 inside the casing 10 so as to rotate together with the shaft 26. Mover 28
are provided with movable contacts 30 and 32.
The distance of the movable contact 30 from the center O of the shaft 26 is greater than the distance from the center O of the movable contact 32. The fixed contacts 14a, 14b for the P position and the fixed contacts 18a, 18b for the N position are connected to the movable element 28.
It is arranged in a position where it can conduct through the movable contact 30 when it rotates about the shaft 26 . In addition, the fixed contacts 16a, 16b, and D for the R position are
Fixed position contacts 20a, 20b, fixed position contacts 22a, 22b, and fixed position contacts 24
a and 24b are arranged at a position where they can be electrically connected by the movable contact 32. A notch 28a is also provided on one end side of the movable element 28. Shaft 26
There is an O-ring 3 in the fitting part between and the casing 10.
4 is provided, and a seal ring 36 is also provided at the fitting portion between the electrode plate 12 and the casing 10. This prevents oil, dirt, etc. from entering the inside of the casing 10. A lever 40 is attached to the outer portion of the casing 10 of the shaft 26 by a nut 38 so as to rotate together with the shaft 26. The lever 40 is connected to a select lever on the driver's seat via a linkage (not shown).

When the select lever on the driver's seat is operated, the lever 40 rotates via a linkage (not shown). The rotation of the lever 40 is transmitted to the movable element 28 via the shaft 26, and the movable element 28 rotates. In the state shown in FIG. 2, the movable element 28 is at a position corresponding to the position of the select lever. Thereafter, when the select lever is moved to the D, N, R, and P positions, the movable element 28 is sequentially moved clockwise in FIG.
Rotate to D, N, R, P positions. , , D and R positions, the movable contacts 32 of the movable element 28 are connected to the fixed contacts 24a-24b, 22a-22, respectively.
b, 20a-20b, and 16a-16b are brought into conduction. In the N and P positions, the movable contact 30 of the movable element 28 is connected to the fixed contacts 18a and 18b for the N position.
And the fixed contacts 14a and 14b for the P position are made conductive. When the fixed contacts 18a, 18b for the N position or the fixed contacts 14a, 14b for the P position are electrically connected, the starter circuit of the engine becomes electrically conductive, and the engine can be started. The accuracy of the conductive range of each fixed contact increases as the distance of the fixed contact position from the center O increases. That is, the further the position of the fixed contact is from the center O, the smaller the possibility that the fixed contact will become conductive when it should not be conductive due to the angular error of the movable element 28. In the case of this automatic transmission inhibitor switch, the fixed contacts 18a, 18b for the N position and the fixed contacts 14a, 14b for the P position are arranged at the farthest position from the center O, and the accuracy of the conduction range is the highest. . Therefore, even though the select lever is in the D position or the R position, the N position fixed contacts 18a, 18b or the P position fixed contacts 14a, 14b will not become conductive. Therefore, safety is further improved. Note that this means that when the fixed contacts 18a, 18b for the N position and the fixed contacts 14a, 14b for the P position are placed at the position closest to the center O allowed for accuracy, the accuracy of the necessary conduction range can be maintained. This means that the inhibitor switch can be made smaller. In particular, the fixed contacts 24a and 24b for the N position are replaced by the fixed contacts 18a and 18b for the N position and the fixed contact 1 for the P position.
4a and 14b, and the movable contact 32 is located closer to the center O than the fixed contact 14 for the P position.
Since it is located on the side farther away than a and 14b,
A part of the external shape of the fan-shaped switch can be made smaller than when the position fixed contacts 24a, 24b are arranged at the same radial position as the N position fixed contacts 18a, 18b. That is, the inhibitor switch can be made smaller by the portion shown by the imaginary line in FIG. 2 (the portion corresponding to the notch 10a). The fixed contacts are fixed in the through holes of the electrode plate 12, but since the fixed contacts are arranged in two radial rows and shifted from each other, a decrease in the rigidity of the electrode plate 12 is prevented.

(f) Effects of the Invention As explained above, according to the present invention, the fixed contacts at the P and N positions are arranged on a circle with a large radius in order to maintain the conduction range accuracy at the P and N positions, which is important for safety. However, since the fixed contact farthest from the P position is arranged on a circle with a small radius, the inhibitor switch can be made smaller. Furthermore, since the movable contacts for the P and N positions and the movable contacts for positions other than the P and N positions are separate, it is possible to prevent poor conduction of the contacts from occurring due to the film generated by sparks. be able to.

[Brief explanation of drawings]

FIG. 1 is a sectional view of an inhibitor switch for an automatic transmission according to the present invention, and FIG. 2 is a sectional view taken along the - line in FIG. 10...Casing, 12...Pole plate, 14a,
14b... Fixed contact for P position, 16a, 16b...
...Fixed contact for R position, 18a, 18b...Fixed contact for N position, 20a, 20b...Fixed contact for D position, 22a, 22b...Fixed contact for position, 24
a, 24b... Fixed contact for position, 26... Shaft, 28... Mover, 30, 32... Movable contact, 40... Lever.

Claims (1)

[Claims] 1. A rotatable movable element having a plurality of movable contacts disposed at mutually different radial positions from the center of rotation inside a substantially fan-shaped casing; P position, N position, and fixed contacts for select positions other than P and N are arranged on a predetermined radial position from the movable rotation center position so as to be electrically connected by the movable contact of P and N. N
The fixed contacts for the positions are arranged on the largest radius position, and the fixed contacts for select positions other than the P and N positions are arranged on the smaller radius positions than the fixed contacts for the P and N positions, and P・N
One of the fixed contacts for the select position other than the above is disposed at least at one end in the circumferential direction of the entire fixed contact array, and one of the movable contacts provided on the movable element is disposed at the one end in the circumferential direction of the entire fixed contact array. The movable contacts corresponding to the fixed contacts for select positions other than P and N are arranged at a small radius position and offset to the one end side with respect to the movable contacts corresponding to the fixed contacts at the P and N positions. A notch is provided at a radially outward position of a movable contact corresponding to a fixed contact for select positions other than P and N, which is arranged at one end in the circumferential direction of the movable element, and a cutout is provided in a substantially fan-shaped position. An inhibitor switch for an automatic transmission, characterized in that a notch is provided on the radially outer side of a fixed contact disposed at one circumferential end of the casing. 2. The inhibitor switch for an automatic transmission according to claim 1, wherein the fixed contact is fixed in a through hole provided in a pole plate supported inside the casing. 3. A rotatable mover equipped with a plurality of movable contacts disposed at mutually different radial positions from the center of rotation inside a substantially fan-shaped casing, and when the mover rotates, one of the movable contacts It has fixed contacts for the P position, the N position, and select positions other than P and N arranged on a predetermined radial position from the movable rotation center position so as to be electrically conductive, and the fixed contacts at the P position and the N position are arranged on the same radial position, fixed contacts for select positions other than the above P and N are arranged on a different radial position from the fixed contacts at the P and N positions, and among the movable contacts provided on the mover, The movable contacts corresponding to the fixed contacts at the P and N positions and the movable contacts corresponding to the fixed contacts for select positions other than the above P and N are arranged on different radial positions similarly to the fixed contacts. An automatic transmission inhibitor switch featuring: 4. The inhibitor switch for an automatic transmission according to claim 1, wherein the fixed contacts at the P position and the N position are arranged at the largest radial position with respect to the rotation center position of the movable element.