JPS635974Y2 - - Google Patents

Description

[Detailed description of the invention] [Field of industrial application] The present invention is a vehicle handbrake, particularly a device for adjusting the length of the cable connecting the handbrake lever placed in the driver's seat and generally the rear wheel brake. It is related to.

[Conventional technology]

As the drum brake's automatic braking gap adjustment device works as the lining wears, the position of the lever supported by the rear brake changes, and the cable gradually becomes taut. Conventionally, an appropriate amount of slack is created in the cable on the handbrake assembly line for the vehicle, but this adjustment work is inefficient and difficult to perform at a vehicle repair shop. It is.

This issue will be explained in more detail. First, as shown in FIG. 1, for the rear wheel brake, an extendable strut 28 is interposed between the webs 23a of a pair of brake shoes 23, and a lever 14 connected to this with a shaft 22 is connected to the strut 28 by a cable. 12 and rotates around the pin 22, the upper brake shoe 23 is moved upward by the tip 14a of the lever 14, and at the same time, the lower brake shoe 23 is moved downward via the strut 28. ,
Each of them is pressed against the inner peripheral surface of a brake drum (not shown) to generate braking force.

The strut 28 is made by connecting a socket 26 connected to the lever 14 with a shaft 22 and a nut 30 that abuts against the lower brake shoe 23 with a threaded shaft 27, and is integral with the threaded shaft 27. The end of the adjustment lever 24 is engaged with the ratchet wheel 27a. When the handbrake is operated, the adjustment lever 24 rotates together with the lever 14 in a counterclockwise direction about the shaft 22, so that the so-called braking gap between the inner peripheral surface of the brake drum and the lining of the brake shoe 23 reaches a predetermined value. If the tip of the adjustment lever 24 is larger than the pawl of the ratchet wheel 27a, the tip of the adjustment lever 24 will fall between the pawls of the ratchet wheel 27a, and when the handbrake is released, the adjustment lever 24 will fall between this and the nut 30. The ratchet wheel 27 is rotated clockwise by the force of the spring 25 stretched between the
Rotate the screw shaft 27 together with the strut 28
Stretch. In this way, a correct braking clearance is always maintained against wear of the lining.

A slit 21 is provided in an immovable back plate 29 that closes the open end of the brake drum, and the tip 14a of the lever 14 projects inward of the brake drum through the slit 21. When the handbrake is released, the lever 14 is moved toward the shaft 2 by the force of the spring 17 that is stretched between the vehicle body side and the lever 14.
A stopper 19, which is urged to rotate clockwise around center point 2 and connected to the lever 14 with a pin 18, is urged against a bracket 29a of the back plate 29.

As shown in FIG. It is connected to the second arm of the relay lever 10. The relay lever 10 is rotatably supported by a support shaft 13 on a bracket 9 fixed to the vehicle body. And relay lever 10
A cable 8 is connected to the third arm of the holder, and this cable 8 is connected to a cable 5 via a turnbuckle 7, and this cable 5 is connected to a relay lever 3, which is further connected to a handbrake lever 1 via a cable 2. By pulling this, the relay lever 10 is rotated clockwise about the support shaft 13, thereby operating the rear wheel brake.

As mentioned above, as the braking gap is adjusted as the lining wears, the strut 28 is extended, causing the shaft 22 to move upward (FIG. 1) and the lever 14 to move upward as a whole. Therefore, the cable 12 will be pulled.
Therefore, if the cable 8 connecting the lever 14 and the handbrake lever 1 is not slackened in advance, the lever 14 will be rotated counterclockwise about the shaft 22, and the brake shoe 23 will be forced to brake. It remains in contact with the drum, causing drag.

In order to eliminate such problems, conventionally, when assembling at the factory, the turnbuckle 7 was first rotated in the direction where the cable 8 was shortened with the handbrake lever in the open (inactive) state, and then the cable 8 was attached to the lever 14. After the stopper 19 is rotated until it is separated from the bracket 29a of the back plate 29, the turnbuckle 7 is rotated in the opposite direction to the above-mentioned direction, and the stopper 1
The turnbuckle 7 is stopped at the position where the turnbuckle 7 contacts the bracket 29a, and from this position, it is further rotated by a predetermined amount of rotation, for example, 1.5 rotations, and finally, the rotation of the turnbuckle 7 is fixed with a lock nut to prevent maximum wear on the breech lining. A slack corresponding to the amount is given to the cable 8.

However, such adjustment work is not only very time-consuming even on a factory assembly line, but also requires considerable skill to perform such work at a maintenance shop when the brake shoe is replaced. If proper adjustment is not made, the handbrake may become less effective or the brake shoe may drag.

[Problem that the invention attempts to solve]

SUMMARY OF THE INVENTION Therefore, an object of the present invention is to provide a handbrake cable length adjustment device that can adjust the tension of the cable between the handbrake lever and the relay lever with a simple operation.

[Means for solving problems]

In order to achieve the above object, the present invention has a configuration in which a first cable is connected to a relay lever connected by a cable to a lever of a drum brake equipped with a braking gap adjustment device, and a second cable is connected to a handbrake lever. A protrusion of a nut that is threadedly engaged with a screw shaft coupled to the first cable is slidably supported in a slit of a frame that is rotatably supported by the first cable;
A compression spring is interposed between the nut and the end wall of the frame, and a lock nut screwed onto the outside of the frame of the screw shaft controls the relative position of the slit of the frame and the protrusion of the nut. is set.

[Effect]

A screw shaft 35 connected to the cable 8 on the rear wheel brake side is screwed into a nut 36 that is slidably supported on the frame 34 of the cable 5 on the handbrake side, and a screw shaft 35 is screwed between the frame 34 and the screw shaft 35. Since a compression spring 38 is interposed between the two cables, by tightening the nut 36, both cables are appropriately tensioned via the compression spring 38. Therefore, the lock nut 39 is tightened to the screw shaft 35 and the compression spring 38 is tightened.
When compressed, both cables are given slack by the amount of compression, and this slack cancels out the increase in cable tension caused by the automatic braking gap adjustment device.

[Example of idea]

The configuration of the present invention will be explained based on an example.
As shown in FIGS. 3 and 4, a boss 32a of a bracket 32 is fixed to the end of the cable 5 connected to the handbrake lever side, and a rectangular frame 3
The lower end wall of the cable 4 is rotatably inserted, and a fixing member 33 is connected to the end of the cable 5 so that the frame 34 does not come off. A hole 4 is provided in the upper end wall of the frame body 34.
A screw shaft 35 connected to the cable 8 connected to the rear wheel brake via the relay lever 10 and screwed into the lock nut 39 is inserted into the frame 34 through the hole 40 and screwed into the nut 36. be done.

As shown in FIG. 5, the nut 36 is integrally provided with a pair of protrusions 36a that protrude radially outward, and these protrusions 36a protrude outward from a slit 37 provided in the side wall of the frame 34. There is. A compression spring 38 is interposed between the nut 36 and the upper end wall of the frame 34, so that a gap s is provided between them. Preferably, one end of the spring 7a, which is stronger than the compression spring 38, is secured to the bracket 32, and the other end is secured to the bracket 16 as shown in FIG.
It is locked in a.

By configuring the present invention as described above, the cable 5 connected to the handbrake lever side is always pulled by the spring 7a, and the slack of the cable 8 connected to the cables 11 and 12 on the rear wheel brake side is absorbed by the frame. It is tensioned by rotating 34.
In other words, if there is slack in the cable 8, the third and fourth
As shown in the figure, the stopper or protrusion 36a abuts against the lower edge of the slit 37 by the force of the compression spring 38, and when the frame body 34 is rotated, the nut 36 is rotated together with this, and the screw shaft 35 is rotated. moves inward of the frame 34, and the cable 8 connected to the rear wheel brake side is gradually pulled.

Furthermore, when the cable 8 is no longer slack due to the rotation of the frame 34, a relative movement occurs between the frame 34 and the nut 36 against the weak compression spring 38, and the protrusion 36a moves upward along the slit 37. trying to start. At this time, as shown in FIG. 3, a gap s is provided between the screw shaft 36 and the frame 34.

Then, when the rotation of the frame 34 is stopped and the nut 39 is tightened, the nut 36 moves upward along the slit 37 and abuts against the upper end wall of the frame 34 as shown in FIG. Therefore, the screw shaft 35 has moved toward the rear brake by the gap s,
The cable 8 becomes slack. If this gap s is determined in advance in relation to the amount of displacement of the lever 14 of the brake gap adjustment device (the amount of tension in the cable 8), the brake gap adjustment device will operate due to wear of the brake shoe and the cables 11 and 12 will be tensioned. Even if the cable 8 is loosened, it will be absorbed by the slack given to the cable 8 in advance.

[Effect of idea]

As described above, the present invention involves threading the screw shaft connected to the rear wheel brake side cable into a nut slidably supported on the frame of the hand brake side cable, and also screwing the screw shaft between the frame body and the screw shaft. Since a compression spring is interposed between the two cables and a lock nut is screwed onto the outside of the frame of the screw shaft, by tightening the nut, both cables are tensioned together via the compression spring. Therefore, by tightening the lock nut to the screw shaft and compressing the compression spring, both cables are given slack in advance by the amount of compression, which offsets the increase in cable tension caused by the automatic braking gap adjustment device. be able to.

And, compared to the conventional method of rotating the turnbuckle and checking that the stopper attached to the lever of the drum brake contacts the bracket on the back plate, the turnbuckle is then returned by a predetermined amount of rotation. It is extremely simple and can be set accurately, greatly improving work efficiency. If you need to readjust the handbrake cable when replacing the brake shoe, you can easily do this at a maintenance shop.

[Brief explanation of the drawing]

Fig. 1 is a plan sectional view of a rear wheel brake equipped with an automatic braking gap adjustment device, Fig. 2 is a plan view showing a schematic configuration of a handbrake device, and Fig. 3 is a length of the handbrake cable according to the present invention. FIG. 4 is a side view of the same side view, FIG. 5 is a front view of the nut, and FIG. 6 is a plan view similar to FIG. 3 showing the state after adjustment. It is a diagram. 1... Handbrake lever, 5, 8... Cable, 10... Relay lever, 11, 12... Cable, 14... Lever, 16a, 32... Bracket, 34... Frame, 35... Screw shaft , 36...
Nut, 38...Compression spring, 36a...Protrusion, 3
7...slit, 40...hole.

Claims (1)

[Scope of Claim for Utility Model Registration] A relay lever connected by a cable to a lever of a drum brake equipped with a braking gap adjustment device has a first
a second cable connected to the handbrake lever, and a protrusion of a nut screwed onto a screw shaft connected to the first cable can be slid into a slit in a frame body rotatably supported by a second cable connected to the handbrake lever. a compression spring is interposed between the nut and the inner end wall of the frame body, and a lock nut screwed onto the outside of the frame body of the screw shaft connects the slit of the frame body and the protrusion of the nut. A length adjusting device for a handbrake cable, characterized in that the relative position of the handbrake cable is set.