JPS6221497Y2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a brake lever device that provides variable leverage using a fixed link in a parking brake.

Automobiles must be equipped with two or more independent brake systems for safety, and for this reason, they generally include a foot brake for decelerating or stopping the vehicle and a parking brake for parking. Brakes for automobiles generally apply the principle of leverage to obtain a large braking force with a small force, but if the lever ratio is increased in order to obtain a large force, there is a correlation that the operating stroke increases. That is, in the case of a handbrake, a brake mechanism with a constant lever ratio produces a large actuation stroke during the initial actuation until a predetermined braking force is obtained, causing a delay in actuation and a poor operating feel. Therefore, during the initial activation of the brake, the lever ratio is small and the stroke of the parking lever is increased, and during the final activation, which requires a large braking force, the brake linkage device provides a variable leverage ratio using three links that increases the leverage ratio. However, unstable frictional force is involved in the leverage conversion, and the change in the leverage is not reliable. Therefore, in the brake lever device according to the present invention,
Furthermore, the aim is to ensure the change in leverage by using fixed links that restrict the actuation.

EMBODIMENT OF THE INVENTION Below, the Example of the brake lever apparatus based on this invention is demonstrated based on drawing.

A bell crank type parking lever 1 is pivotally supported by a pin 3 on a bracket 2 fixed to the floor of the driver's cab of an automobile, and one arm 1a is provided with a long hole 4 in the radial direction of the pin 3. . One end of a pin 6 fixed to the end of the brake cable 5 is slidably engaged in the elongated hole 4. The other end of the pin 6 is engaged with an inclined groove 7 provided upward in the direction of rotation of the parking lever 1 of a plate fixed to the lower side of the bracket 2 so as to form a fixed link.

Therefore, when the other arm 1b of the parking lever 1 is rotated in the direction of arrow A during braking, the pin 6
The lever ratio is steadily increased from a/b1 to a/b2 while taking the position of the intersection of the inclined groove 7 and the elongated hole 4. Therefore, when the brake is initially activated, the brake cable is connected with a small leverage ratio. The stroke is made large, and at the final stage of operation, the lever ratio is made large so that a large braking force can be reliably obtained with a light operating force.
Furthermore, if the parking lever 1 is returned to its original position when the brake force is released, the pin 6 will reliably return to the tip of the elongated hole 4, thereby reliably preventing the brake from dragging.

As can be understood from the above explanation, in the brake lever device that provides a variable leverage according to the present invention, the transition of the leverage ratio is regulated to a constant, and the long hole of the parking brake lever, which is a component of the leverage ratio, This eliminates discontinuous movement of the pin due to the influence of frictional force at the point of contact with the pin at the end of the cable, providing a better operating feel and eliminating stepped wear that can occur in the long hole of the parking brake lever. Accidents in which the pin becomes unlatched and the brake loosens for some reason after applying the parking brake can be eliminated by applying a stroke to the parking brake lever, making it practical. The effect is significant.

[Brief explanation of the drawing]

The figure shows an embodiment of a brake lever device providing variable leverage according to the present invention. 1... Parking brake lever, 2... Bracket, 3... Pin, 4... Long hole, 5... Brake cable, 6... Pin, 7... Slanted groove.

Claims (1)

[Scope of utility model registration request] In a brake lever device in which a pin provided at the tip of a parking cable is slidably engaged with a long hole provided in the parking brake lever, a long groove is provided that engages with the pin and regulates the movement position of the pin. 1. A brake lever device providing a variable leverage, characterized in that the fixed link is provided with a fixed link, and the leverage is increased in accordance with the actuation stroke of the parking brake lever.