JPH03261018A - Switch for parking brake - Google Patents

Abstract

PURPOSE:To improve sureness of a switch for parking brake besides making it simple and small-sized by detecting that a braking action by a parking lever is surely executed through a Hall IC and a magnetized movable body. CONSTITUTION:The main constitutional parts of a switch 11 consist of a movable body 14, in which a magnet 15 is embedded, and a Hall IC 17 corresponding thereto. The movable body 14 is interlocked to a piston 13 responding to an action of a parking lever 10. The Hall IC 17 embedded in a case 16 has a magnetic - electric conversion circuit function so as to rapidly generate an input voltage at the time of reaching prescribed magnetic flux density due to a change of a distance from the magnet 15. Thereby, the Hall IC 17 rapidly outputs voltage at the position of the movable body 14, where a correct braking action is performed by the parking laver 10 to flash an alarm lamp 12.

Description

DETAILED DESCRIPTION OF THE INVENTION [Industrial Field of Application] The present invention relates to a switch that changes when a parking brake is activated or deactivated.

[Prior Art] Generally, a parking brake warning light is provided on an instrument panel to inform the driver whether the parking brake is in an activated position or a non-activated position. This warning light is turned on or off by a single switch linked to the parking lever. That is, when the parking brake is set to the operating position, the above switch is turned on and the warning light lights up. Furthermore, when the parking brake is set to the inactive position, the above switch is turned off and the warning light goes out.

[Problems to be Solved by the Invention] However, since the on position and the off position of the switch are almost the same, the switch is designed with priority given to preventing the parking brake from dragging during driving. Therefore, even when the parking brake is in the operating position but not in a state where the brake is applied reliably, that is, when the parking lever is pulled to a shallow position, the above switch will turn on or off and turn on or off the warning light. The lights are turned off.

As a result, for example, when the vehicle is parked on a slight slope, if the parking lever is pulled too shallow, the switch turns on and the vehicle starts moving in the direction of the slope even though the warning light is on. There was a point.

SUMMARY OF THE INVENTION An object of the present invention is to provide a parking brake switch that takes up little space and has a simple configuration, and that can be switched only by reliable operation of the parking lever.

Another object of the present invention is to prevent the parking brake from dragging when driving, and to prevent the vehicle from moving in the direction of an incline when parking on a slope despite pulling the parking lever. The purpose of the present invention is to provide a parking brake switch that can be used.

[Means for Solving the Problems] In order to achieve the above object, the present invention provides a shaft whose one end is interlocked with a parking lever, a movable body fixed to the shaft and whose surface is magnetized, and a movable body that covers the movable body. The device includes a case made of a non-magnetic material and a switch-type output type Hall IC provided in the case facing the magnetized surface of the movable body.

[Function] When the shaft moves to a position where the parking brake can reliably apply the brake, the Hall IC is switched on or off by the movable body, and when the shaft returns to the position where the brake is completely inactive, The Hall IC is switched off or on by the movable body.

[Example] Next, an example of the present invention will be described in detail based on the drawings.

- As shown in FIGS. 1 and 3, 10 is a parking lever of a vehicle parking brake, and 11 is a switch that detects activation or non-activation of the parking brake. This switch 11 includes a shaft 13, a movable body 14, a magnet 15, a case 16, a Hall IC 17, a compression coil spring 18, and a stopper 19. A warning light 12 provided on the instrument panel of the driver's seat (not shown) is connected to the Hall IC 17.

One end of the shaft 13 abuts against a plate 21 fixed near the pivot shaft 10a of the parking lever 10. The movable body 14 is formed into a tapered truncated pyramid shape, and the other end of the shaft 13 is fixed to the base end thereof. The magnet 15 is buried along one side of the movable body 14 that is inclined with respect to the moving direction of the movable body 14 . The case 16 has a bottom made of non-magnetic resin, and is shaped like a rectangular parallelepiped box that encloses the movable body 14 so that the movable body 14 can move by a distance S. Further, in the center of one surface of the case 16, a cylindrical body 16a communicating with the inside of the case 16 is formed integrally with the case 16,
A shaft 13 fixed to a movable body 14 is attached to this cylindrical body 16a via a bearing 22 so as to be slidable in the axial direction thereof. Further, one end of the shaft 13 protrudes from the case 16, and a bellows 23 is attached to the portion of the shaft 13 that protrudes from the case 16. The bellows 23 has dust etc. in case 16.
This prevents the particles from entering the inside and adhering to the bearing 22.

The Hall IC 17 is a switch-type output type magnetic sensor, and is embedded in the inner wall of the case 16 facing the magnet 15. This Hall IC 17 is a solid-state element with a magneto-electric conversion circuit function in which a Hall element and a circuit for amplifying and controlling the output voltage are formed in one crystal, and is turned on and off by the magnetic flux density acting on the Hall IC 17. Output voltage is obtained.

Further, the Hall IC 17 is provided with hysteresis with respect to the magnetic field, as shown in FIG. 2, in order to ensure its switching operation. Hall IC17 has increased magnetic flux density,
When the predetermined magnetic flux density M is reached, the output voltage suddenly rises to a high level voltage H and is turned on. Further, the magnetic flux density of the Hall IC 17 decreases, and when the magnetic flux density reaches a predetermined value, the output voltage rapidly decreases to a low level voltage G close to O volts, and is turned off.

Due to the hysteresis of the Hall IC 17, the inclination angle of the magnet 15 with respect to the moving direction of the movable body, and the excitation force of the magnet 15, when the movable body 14 moves to the position shown by the two-dot chain line in FIG. Lever 1
When the brake lever 0 is pulled to a deep position (the position of the parking lever 10 indicated by the two-dot chain line in FIG. 3) to ensure that the brake is applied, the Hall IC 17 is turned on and the warning light 12 is turned on. Ru. Moreover, the movable body 14
When the driver returns to the position shown by the solid line in the figure, that is, when the driver returns the parking lever 10 to the position where the brake action is completely inactive (the position of the parking lever 10 shown by the solid line in Fig. 3), The IC 17 is configured to turn off the warning light 12. The compression coil spring 18 has one end inserted into a recess 14a formed at the tip of the movable body, and the other end inserted into four parts 19a formed on the inner wall of a stopper 19 attached to the case 16, so that the movable body 14 is inserted into a plate. 21 side.

Next, the operation of the parking brake switch configured as described above will be explained.

When parking the vehicle, the driver operates the parking lever 10 in the direction of the solid arrow in FIG. 3. With this operation, as shown in FIG. 1, the plate 21 fixed to the parking lever 10 moves in the direction of the solid arrow. The shaft 13 is pushed into the plate 21, and the movable body 14 reaches the position shown by the two-dot chain line. At this time, the driver pulls the parking lever 10 deeply to ensure the braking action, and the magnet 15 comes closest to the Hall IC 17, increasing the magnetic flux density acting on the Hall IC 17 to M.

This magnetic field causes the output voltage of the Hall IC 17 to rapidly rise to H, and since this output voltage is applied to the parking brake warning light 12, the warning light 12 lights up. As a result, even if the parking place is sloped, the parking brake is reliably activated and the vehicle will not start moving in the direction of the slope.

When starting the vehicle, the driver operates the parking lever 10 in the direction of the dashed arrow in FIG. With this operation, as shown in FIG. 1, the plate 21 moves in the direction of the dashed arrow.Since the movable body 14 is biased by the compression coil spring 18, one end of the shaft 13 comes into contact with the plate 21. The shaft 13 moves in the direction of the dashed arrow,
The movable body 14 reaches the position shown by the solid line. At this time, the driver has completely returned the parking lever 10 and the brake action is completely inactive, the magnet 15 is farthest away from the Hall IC 17, and the magnetic flux density acting on the Hall IC 17 decreases to L.

Due to this magnetic field, the output voltage of the Hall IC 17 suddenly drops to O volts, so the parking brake warning light 1
2 goes out. As a result, it is possible to prevent the parking brake from dragging when the vehicle is running while the parking brake is applied, so it is possible to prevent wear of the brake liner and wasteful consumption of fuel.

In the embodiment, a magnet is embedded in a truncated pyramid-shaped movable body, but this is just an example, and the movable body itself may be formed of a magnet.

In the embodiment, the movable body is formed in the shape of a truncated pyramid, and the magnet is embedded along the sides of the movable body that are inclined with respect to the moving direction of the movable body. Only the movable body may be provided so as to be inclined with respect to the moving direction of the movable body.

In addition, the direction of inclination of the magnet is tilted in the opposite direction from the example, so that the switch is turned off when the plate is pushing the shaft, and the switch is turned on when the plate is not pushing the shaft. Good too.

In addition, although the compression coil spring can be installed between the tip of the movable body and the inner wall of the stopper of the case, it is not limited to this. good.

Also, instead of a compression coil spring, a tension coil spring is used. 0 Alternatively, an elastic body such as rubber may be used.

One end of the shaft may be pivotally connected to the plate so that the shaft reciprocates as the parking lever is operated. With this configuration, the elastic body becomes unnecessary.

Although the parking lever is a bar type, it is not limited to this and can also be applied to a stick type.

In addition, this switch was constructed so that a plate protruded from the parking lever and one end of the shaft came into contact with this plate, but this is just an example, and the plate is attached to a member such as a wire that moves with the operation of the parking brake. It may be configured such that the shaft is attached and one end of the shaft is in contact with the shaft.

Furthermore, although we have mentioned Hall ICs that turn on when the magnetic flux density increases and turn off when the magnetic flux density decreases, this is not the only example. Hall ICs that turn on when the magnetic flux density decreases and turn off when the magnetic flux density increases can also be used. good.

[Effects of the Invention] As described above, according to the present invention, when the shaft moves to a position where the braking action by the parking brake is reliably performed, the Hall IC is switched on or off, and the braking action is completely disabled. Hall I so that it switches off or on when the shaft returns to the operating position.
C and a magnet are installed, it is possible to prevent the parking brake from dragging when driving, and it is possible to prevent the vehicle from moving in the direction of the slope even if the parking brake is pulled when parking on a slope. can.

Furthermore, since it can be constructed compactly with only a few parts, it has the advantage of requiring only a small amount of installation space.

[Brief explanation of drawings]

FIG. 1 is a longitudinal sectional view of a parking brake switch according to an embodiment of the present invention. FIG. 2 is a switch operation characteristic diagram showing the relationship between the output voltage and the magnetic flux density of the Hall IC. FIG. 3 is a side view of the parking lever including the switch. 10: Parking lever switch, shaft, movable body, magnet, case, Hall IC6 3

Claims (1)

[Scope of Claims] A shaft interlocked with a parking lever; a movable body fixed to the shaft and having a magnetized surface; a case made of a non-magnetic material and provided to enclose the movable body; and a case of the movable body. A parking brake switch comprising a switch-type output-type Hall IC provided in the case facing a magnetized surface, wherein the Hall IC and the movable body ensure that braking action by the parking brake is performed. When the shaft moves to a position where the brake is turned off, the movable body switches the Hall IC on or off, and when the shaft returns to a position where the brake action is completely disabled, the movable body switches the Hall IC off. or a parking brake switch, characterized in that it is arranged to be turned on.