JP2005116446A - Anti-adhesion structure of dirt in pedal switch - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To prevent dirt such as dust from adhering to a sliding part of a plunger in a pedal switch, without giving rise to increase in the number of parts and man-hours. <P>SOLUTION: A cover (a cup-shaped part 9a) covering tip parts of a guide member 14 and a plunger 15 is integrated with a stopper 9 with which a tip of the plunger comes in contact when a pedal lever 2 supported in free swinging movement to a car body is not in operation. With this, the tip parts of the guide member and the plunger are covered with the cover when the pedal lever is not in operation, so that dirt such as dust is prevented from sticking to the sliding part of the plunger. In particular, the cover can be integrally formed with the stopper, so that the number of parts and man-hours need not be increased. <P>COPYRIGHT: (C)2005,JPO&NCIPI

Description

  The present invention relates to a structure for preventing adhesion of foreign substances in a pedal switch for detecting an operating state of a pedal.

  In order to light a stop lamp provided at the rear of the vehicle body in conjunction with the brake pedal, a pedal switch for detecting that the brake pedal has been depressed is provided in the automobile. The pedal switch includes a casing in which a fixed contact is incorporated and fixed to the vehicle body side, and a plunger that is slidably coupled to a cylindrical guide member that is integrally formed with the casing and that is interlocked with the movable contact. The electrical continuity between the fixed contact and the movable contact is interrupted by advancing and retreating movement in conjunction with the swinging movement of the brake pedal of the plunger protruding from the front end opening.

As this pedal switch, a structure is known in which a sealing member made of a flexible film is attached immediately before the contact mounting portion to prevent foreign matters such as dust from entering the contact portion and causing poor contact. (See FIG. 6 of Patent Document 1).
Japanese Patent Publication No. 6-101272

  However, according to the conventional structure, it is impossible to prevent dust from adhering to the portion protruding from the guide member of the plunger. Incorporating a seal member in the inside of this type of switch made up of small parts increases the number of parts and the number of assembly steps, leading to an increase in the manufacturing cost of the switch.

  In order to solve such problems and make it difficult for foreign matter to adhere to the sliding portion of the plunger 15 in the pedal switch 7 without increasing the number of parts and the number of assembly steps, claim 1 of the present invention provides a vehicle body. A cover (a cup-shaped portion 9a) that covers the guide member and the tip of the plunger is integrally provided on the stopper 9 that contacts the tip of the plunger when the pedal lever 2 that is swingably supported on the side is not operated. Was characterized.

  According to the second aspect of the present invention, the inner diameter dimension of the cover in the above-described configuration is set to a size capable of loosely receiving the front end of the guide member.

  According to the present invention, when the pedal lever is not operated, the guide member and the distal end portion of the plunger are always covered with the cover, so that foreign matters such as dust do not adhere to the sliding portion of the plunger. In particular, since the cover can be integrally formed with the stopper, it is not necessary to assemble a cover of another member to the switch, so that it is not necessary to increase the number of parts and the number of assembly steps. Further, by making the inner peripheral diameter of the cover relatively large, the stopper can be assembled without being affected by variations in positional accuracy between the members.

  Hereinafter, the present invention will be described in detail with reference to the accompanying drawings.

  FIG. 1 shows the periphery of a brake pedal to which the present invention is applied. The lever 2 of the brake pedal 1 is supported by a pedal bracket 4 fixed to the inner surface of the dashboard upper 3 so that the upper end of the lever 2 can swing with a pin 5. And the intermediate part of the lever 2 is connected with the piston of the master cylinder which is not illustrated.

  A switch bracket 6 is integrally provided on the upper part of the pedal bracket 4, and a pedal switch 7 according to the present invention is attached to the switch bracket 6.

  A stopper bracket 8 is welded to the side surface of the lever 2. A stopper 9 made of a relatively soft rubber material is attached to the stopper bracket 8 at a position corresponding to the attachment position of the pedal switch 7.

  As shown in detail in FIG. 2, the pedal switch 7 includes a cylindrical casing 12 having both ends opened and a partition wall 11 provided in an axially intermediate portion, a cover 13 that closes one opening of the casing 12, Between the plunger 15 slidably engaged with the guide portion 14 having a small-diameter cylindrical shape integrally formed with the cover 13, the fixed contact 16 provided on one opening surface side of the casing 12, and the intermediate partition wall 11 and the fixed contact 16. A movable contact 18 that is elastically supported by a coil spring 17, a coil spring 19 that elastically biases the plunger 15 in a protruding direction, and a fixed contact 16, and is connected to the other opening side of the casing 12. The terminal pin 20 is provided internally. The other opening side of the casing 12 forms a male coupler C that connects a fixed contact to a stop lamp circuit (not shown).

  The plunger 15 is prevented from coming off with its tip protruding somewhat from the opening of the guide portion 14. By pushing the plunger 15 against the elastic force of the coil spring 19, the inner end of the plunger 15 is stopped. As a result, the movable contact 18 is separated from the fixed contact 16 and the electrical continuity is cut off.

  The pedal switch 7 is fixed to the switch bracket 6 by screwing a male screw formed on the outer peripheral surface of the guide portion 14 with a female screw formed on a synthetic resin clip 21.

  As a result, when the brake pedal 1 is not operated, the plunger 15 of the pedal switch 7 is pushed in contact with the stopper 9 provided on the lever 2, the power supply to the stop lamp circuit is cut off, and the stop lamp is turned off. When the brake pedal 1 is depressed, the stopper 9 moves away from the tip of the plunger 15, the plunger 15 protrudes, the movable contact 18 contacts the fixed contact 16, current flows to the stop lamp circuit, and the stop lamp is turned on.

  The stopper 9 has an open cup shape, and its bottom wall 9b is attached to the stopper bracket 8. When the brake pedal 1 is not operated, the tip of the plunger 15 contacts the inner surface of the bottom wall 9b. It comes to touch. The distal end portions of the plunger 15 and the guide portion 14 are loosely received inside the cup-shaped portion 9a. In this way, by setting the inner peripheral diameter of the cup-shaped portion 9a to a size that can accept the tip of the guide portion 14 loosely, the stopper 9 is assembled without being affected by variations in positional accuracy between the members. be able to.

  According to this stopper 9, when the brake pedal 1 is not operated, it is received inside the cup-shaped portion 9a of the stopper 9 and the opening end of the guide portion 14 and the tip end portion of the plunger 15 are covered. It is possible to prevent foreign matters such as dust from adhering to the sliding portion of the plunger 15.

  While the brake pedal 1 is depressed, the opening end of the guide portion 14 and the tip end portion of the plunger 15 are exposed, but the exposure time is overwhelmingly shorter than the concealed time. Is almost negligible.

  The present invention has been described in detail by exemplifying a switch having a so-called normally closed contact that opens when an external force is applied to the plunger 15. However, the present invention is not limited to the above, and the contact is opened when an external force is applied to the plunger 15. The present invention is equally applicable to normally open contact switches configured to close. Furthermore, while the above embodiment has only been applied to the case where the contact is closed at the initial stage of the pedal stroke, the present invention provides a clutch interlock mechanism that prevents the engine from starting unless the clutch pedal is fully depressed, for example. As described above, the present invention is also applicable to a configuration in which the contact is closed when the pedal is fully depressed.

  The structure for preventing the adhesion of foreign matters in the pedal switch according to the present invention can prevent foreign matters such as dust from adhering to the sliding portion of the plunger in the pedal switch without increasing the number of parts and the number of assembly steps. It is useful as a dust-proof structure for plunger type limit switches.

It is a side view of the brake pedal periphery to which the present invention is applied. It is sectional drawing of the pedal switch to which this invention was applied.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Brake pedal 2 Lever 7 Pedal switch 9 Stopper 9a Cup-shaped part 14 Guide part 15 Plunger

Claims (2)

In order to detect the operating state of a pedal lever that is swingably supported on the vehicle body side, it is a structure for preventing the adhesion of contaminants in a pedal switch that includes a plunger that is slidably supported by a guide member fixed on the vehicle body side. And
A stopper that contacts the tip of the plunger when the pedal lever is not operated is provided, and a cover that covers the guide member and the tip of the plunger is integrally provided on the stopper. Adhesion prevention structure.   2. The structure for preventing adhesion of foreign matters in a pedal switch according to claim 1, wherein an inner diameter of the cover is a size capable of loosely receiving a tip portion of the guide member.

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