JP3738263B2 - Vehicle disc brake - Google Patents

Description

  The present invention is a brake device for a bar handle vehicle that steers a vehicle body with a handle bar, such as a motorcycle, a three-wheeled vehicle, a three- or four-wheeled buggy, a golf cart, or a snowmobile, and particularly uses a brake lever. The present invention relates to a brake device configured to operate a mechanical rear wheel brake with the pressure of a hydraulic master cylinder.

As a conventional technology that combines a mechanical brake with a hydraulic system that generates hydraulic fluid in the hydraulic master cylinder by operating the brake lever, the hydraulic pipe connected to the hydraulic master cylinder and the mechanical brake are pulled. An actuator is interposed between the brake cable and the hydraulic operation of the hydraulic master cylinder is converted into a mechanical operation by the actuator to operate the mechanical brake. While making use of both functional characteristics, the loss due to the elongation of the brake wire can be reduced to improve the rigidity of the brake lever, and the vapor lock can be prevented from being generated by braking heat (for example, see Patent Document 1). .)
Japanese Utility Model Publication No. 2-57767

  By the way, when a braking force is applied to a running vehicle, the weight of the vehicle body moves to the vehicle body front side due to the inertial force, and the vehicle body rear side load necessary for rear wheel braking becomes small. It is well known that it is preferable to reduce the pressure fluid appropriately. However, when the mechanical brake described above is applied to a rear wheel brake of a bar handle vehicle, a PCV (pressure control valve) or a P valve (proportional) is used. A hydraulic pressure reducing means such as a valve has to be provided separately, and the increase in cost, the weight of the vehicle body, and the number of assembling work are inevitable.

  Therefore, the present invention applies a mechanical brake that operates with the hydraulic pressure of the hydraulic master cylinder to the rear wheel brake, and uses an actuator with a simple internal structure without using a separate hydraulic pressure reducing means. The purpose is to reduce the braking force to the rear wheel so that the input / output pressure for the rear wheel brake approaches the ideal distribution.

The present invention provides a hydraulic pipe connected to a hydraulic master cylinder operated by a brake lever, connecting means for pulling a mechanical rear wheel brake, and arranged between the hydraulic pipe and the connecting means. A bar handle vehicle brake device comprising an actuating force conversion actuator provided , wherein the actuator defines a cylinder hole in a cylinder body into a hydraulic chamber and an atmospheric chamber by a piston integrated with a cylinder rod. and, the leading end of the cylinder rod while projecting to the outside from the bottom wall of the liquid chamber, the air chamber, by disposing the slide plate, across the slide plate, the set load to the piston side A small spring and a spring with a large set load are contracted on the side opposite to the piston, and the bottom wall of the cylinder body on the atmospheric chamber side is Ventilation holes for sucking and exhausting air in the air chamber are formed, the hydraulic pipe is connected to the hydraulic chamber, and the connecting means is directly connected to the tip of the cylinder rod to operate the brake lever. The piston is pushed toward the atmospheric chamber while compressing the two springs by the pressurized liquid entering the hydraulic pressure chamber, and the mechanical brake is pulled by pulling the connecting means by the cylinder rod. It is characterized by operating .

  In addition to the direct connection, the cylinder rod of the actuator may be connected with an appropriate transmission means such as a link mechanism. In addition, when a mechanical drum brake is used as the rear wheel brake, it does not occupy a large arrangement space unlike the mechanical disk brake that the disk rotor and caliper body protrude, so the wheel of the rear wheel A scooter type vehicle with a small diameter and equipped with a power unit that integrates an engine, power transmission mechanism, and transmission mechanism on one side of the rear wheel uses the wheel hub as a brake drum and accommodates the drum brake in the wheel hub. Can be arranged.

  According to the above invention, the hydraulic fluid generated in the hydraulic master cylinder by the grip lever operation is supplied from the hydraulic piping to the hydraulic chamber of the actuator, and the piston is pushed toward the atmospheric chamber while expanding the hydraulic chamber. The cylinder rod integrated with the piston is slid, and the cylinder rod pulls the connecting means to operate the rear wheel brake.

  Of the two springs set in the atmospheric chamber, one spring with a low set load is compressed at the initial stage of movement of the piston. When the set load of one spring increases to the set load of the other spring having a high set load, the two springs are compressed while moving the slide plate sandwiched therebetween.

  The compression load of the two slip rings that are compressed by the movement of the piston becomes the stroke resistance of the cylinder rod, and in the first half of the braking of the piston where only one spring with a low set load is compressed, the cylinder rod strokes greatly, In the latter half of the braking when the other heavy spring is also compressed, the stroke resistance increases and the stroke amount of the cylinder rod decreases. Therefore, the actuating force of the rear wheel brake that is pulled by the cylinder rod through the connecting means is reduced from the stage where the other spring having a high set load is compressed. Power is weakened.

  According to the bar handle vehicle brake device of the present invention, the actuator reduces the actuating force in the latter half of braking of the rear wheel brake in addition to the actuating force converting function for converting the hydraulic actuating force to the rear wheel brake into the mechanical actuating force. In addition to using a small and inexpensive mechanical brake for the rear wheel brake, the mechanical brake can be rearranged without using a separate hydraulic pressure reducing means such as a PCV or P valve. A good braking force as a wheel brake can be set at a low cost, and the weight of the vehicle body can be reduced and the number of assembly work steps can be reduced.

  In addition, since the actuator has a simple structure, it can be manufactured at a lower cost while improving reliability and durability. In addition, when a mechanical drum brake is used for the rear wheel brake, the drum brake can be stored in the wheel hub of the rear wheel, and a disc rotor or caliper body is placed on the side of the rear wheel like the disc brake. Occupies less space, so the soft wheel with a particularly small rear wheel diameter, the rear wheel has a small wheel diameter, and the engine, power transmission mechanism and transmission mechanism are integrated on one side of the rear wheel. It is suitable for a scooter type vehicle provided with a power unit.

  Hereinafter, an embodiment of the present invention will be described with reference to FIG. In the brake device 1, the front wheel brake 4 and the rear wheel brake 5 are operated by a brake operation means provided at one end portion of the body steering handle bar of the bar handle vehicle.

  The brake operation means 2 is a combination of a brake lever 6 and a tandem hydraulic master cylinder 7, and two hydraulic pipes 8 and 9 for front and rear wheel brakes are connected to the hydraulic master cylinder 7. The front and rear wheel brakes 4 and 5 are simultaneously actuated by the hydraulic fluid generated in the hydraulic master cylinder 7 by the gripping operation of the brake lever 6.

  The front wheel brake 4 uses a hydraulic disc brake that operates the caliper body 10 with the hydraulic pressure generated in the hydraulic master cylinder 7 to brake the disc rotor 11, and the caliper body 10 includes a front wheel brake. The hydraulic pipe 8 is connected. Further, a mechanical drum brake pulled by a brake cable 12 is used for the rear wheel brake 5, and the brake cable 12 has one end portion via an actuator 40 and a hydraulic pipe 9 for rear wheel brake. The other end is connected to an operating lever 14 pivotally supported on the back plate 13 of the rear wheel brake 5.

  A hydraulic pressure control device 17, generally called ABS (anti-lock brake system), is interposed in the hydraulic pressure pipes 8 and 9, and pressure fluid supplied from the hydraulic pressure master cylinder 7 to the hydraulic pressure piping 8 and 9 is received. When it is excessive in light of the vehicle speed and road surface condition, this is adjusted by the hydraulic pressure control device 17 so that the front and rear wheels can be effectively locked and the shortest braking distance can be stopped with a stable vehicle posture. ing.

  The actuator 40 is an operating force converting mechanism that converts the hydraulic operating force from the brake operating means 2 for the rear wheel brake 5 into a mechanical operating force, and the cylinder hole 43 in the cylinder body 42 is integrated with the cylinder rod 41. The piston 44 defines a hydraulic pressure chamber 45 and an atmospheric pressure chamber 46, and a hydraulic pressure pipe 9 for rear wheel braking is connected to the hydraulic pressure chamber 45. The cylinder rod 41 disposed on the central axis of the hydraulic chamber 45 and the atmospheric chamber 46 protrudes from the bottom wall of the hydraulic chamber 45 to the outside, and the brake cable 12 for the rear wheel brake cable is directly connected to the tip thereof. Has been.

The atmosphere chamber 46 is provided with a spring 48 having a small set load on the piston side and a spring 49 having a large set load on the anti-piston side with the slide plate 47 interposed therebetween, and the atmosphere chamber of the cylinder body 42. A vent hole 50 is formed in the side bottom wall for sucking and exhausting air in the atmospheric chamber 46 when the springs 48 and 49 are expanded and contracted.

  The hydraulic fluid branched from the hydraulic master cylinder 7 to the hydraulic piping 9 for the rear wheel brake by the gripping operation of the brake lever 6 enters the hydraulic chamber 45 of the actuator 40 and compresses both springs 48 and 49. The piston 44 is pushed toward the atmosphere chamber. The cylinder rod 41 is drawn into the cylinder body by the movement of the piston 44, pulls the brake cable 12, rotates the operation lever 14, and operates the rear wheel brake 5.

  On the rear wheel brake 5 side after releasing the above-described braking operation, the return spring 29 that has been compressed by the rotation of the operating lever 14 during braking is restored in the extending direction, and the brake cable 12 is pulled in the rear wheel brake direction. Then, the cylinder rod 41 of the actuator 40 is pulled out from the cylinder body, and the hydraulic fluid that has expanded in the hydraulic chamber 45 is returned to the hydraulic master cylinder 7 to return to the non-operating state.

Furthermore, in the above embodiment has been described with reference to brake cable interlocking means for the rear wheel brake, Dari connecting a plurality of rods, Ru possible der using both the rod and the brake cable. In the present embodiment, the hydraulic operation of the rear wheel brake has been described in conjunction with the front wheel brake. However, the present invention can also use a hydraulic system for the rear wheel brake.

  In addition, when a mechanical drum brake is used for the rear wheel brake, the drum brake can be stored in the wheel hub of the rear wheel, and the disc rotor and caliper body space is provided on the side of the rear wheel like the disc brake. Since there is no need to occupy, a soft bike with a small rear wheel diameter and a power unit that integrates an engine, a power transmission mechanism, and a speed change mechanism on one side of the rear wheel with a small rear wheel diameter. Suitable for scooter type vehicles.

Schematic of a bar handle vehicle brake device showing a first embodiment of the present invention.

Explanation of symbols

    DESCRIPTION OF SYMBOLS 1 ... Brake apparatus, 2 ... 1st brake operation means, 4 ... Front wheel brake using hydraulic type disc brake, 5 ... Rear wheel brake using mechanical drum brake, 6 ... Brake lever, 7 ... Hydraulic master cylinder, 8 ... Hydraulic piping for front wheel brakes, 9 ... Hydraulic piping for rear wheel brakes, 12 ... Brake cable for pulling rear wheel brakes, 13 ... Back plate, 14 ... Operating lever, 29 ... Return spring, 40 ... Actuator, 41 ... Cylinder rod, 42 ... Cylinder body, 43 ... Cylinder hole, 44 ... Piston, 45 ... Hydraulic chamber, 46 ... Air chamber, 47 ... Slide plate, 48 ... Spring with small set load, 49 ... Set load Big spring

Claims (1)

Hydraulic piping connected to the hydraulic master cylinder operated by the brake lever, connecting means for pulling the mechanical rear wheel brake, and operating force disposed between the hydraulic piping and the connecting means a bar handle vehicle brake system and an actuator for the conversion, wherein the actuator Enashi the cylinder body of the cylinder bore in the hydraulic pressure chamber and an atmospheric chamber at the cylinder rod integral with a piston, said cylinder Protruding the tip of the rod to the outside from the bottom wall of the hydraulic pressure chamber, arranging a slide plate in the atmospheric chamber, sandwiching the slide plate, a spring with a small set load on the piston side, A spring having a large set load is contracted on the non-piston side, and the air chamber side bottom wall of the cylinder body is emptied when the springs extend and contract. The hydraulic pressure pipe is connected to the hydraulic pressure chamber, the connecting means is directly connected to the tip of the cylinder rod, and the hydraulic pressure is controlled by operating the brake lever. The piston is pushed toward the atmosphere chamber while compressing both springs by the pressure liquid entering the chamber, and the mechanical brake is pulled by pulling the connecting means with the cylinder rod. A bar handle vehicle brake device.

Images