JPS59222630A - Centering mechanism of shoe in drum brake clutch - Google Patents

Abstract

PURPOSE:To decrease a manufacturing cost, by mounting a protrusive member in the variable position of its mounting by a bolt to a U-groove provided in the side of a piston opposite to a hydraulic cylinder. CONSTITUTION:A half moon shaped protrusive member 18, being inserted into a U-groove 4' provided in the side of a piston opposite to a hydraulic cylinder 4, is mounted in the variable mounting position of said member by a bolt 19, while a recessed part 20 fitted to the protrusive member 18 is formed in the end part of a shoe 5. In this way, even if the shoe 5 is inaccuratelt molded, a mounting position of the protrusive member 18 can be adjusted when it is assembled. Accordingly, a manufacturing cost is decreased by less severely requiring the accuracy of parts when they are manufactured.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to an improvement in a brake/clutch mechanism that makes sliding contact with the inner surface of a drum. The present invention relates to a drum type brake/clutch mechanism, or a drum type brake/clutch mechanism in which an actuating device is disposed between one end of two shoes adjacent to each other and the other end is rotatably supported.

Conventionally, drum type brake/clutch mechanisms using hydraulic cylinders are well known.

This known mechanism uses a hydraulic cylinder to expand the shoe.
Although the drum is compressed and brought into contact with and separated from the inner surface of the drum, the following problems could not be avoided.

Because the shoes are not positioned accurately, the shoes come into contact with the inner surface of the drum, causing drag and preventing accurate half-braking.
Half-clutch operation was difficult. The object of the present invention is to improve the above-mentioned problems and provide a shoe centering mechanism for a drum type brake/clutch that has a simple structure and high precision.

An embodiment will be described below with reference to the drawings.

Reference numeral 1 denotes a fixing portion, which has a fixing portion 2 of the fang 1 and a second fixing portion 3 protruding from each other in substantially point-symmetrical positions. Each of the first fixing parts 2K is equipped with an actuating device such as a hydraulic cylinder 4, and the second fixing part 3 has a shoe 5 displaceable in the radial direction, and a support part is provided to adjust and restrict the falling of the shoe 5. 7 is supported.

The shoe 5 has an arcuate shape, and a lining 6 is attached to the outer periphery.

Two springs 8, 8, are attached to this shoe 5, sandwiching the support part 7 between it and the second fixed part 3, and these springs 8 pull the shoe 5 toward the center of the drum 24. It is constantly energized to bring it closer together. The shoe 5 has an arcuate end that is connected to the drum 2 by a piston 9 (actuator) of the hydraulic cylinder 4.
It moves forward and backward in four directions, and the other end is rotatably supported on the side opposite to the piston of a hydraulic cylinder 4 attached to the fixed part 2 of the spear 1.

The piston sides of the hydraulic cylinder 4 and shoe 5 are fitted as follows.

The piston 9 of the hydraulic cylinder 4 has a contact surface 10 at its tip.
A rod 23 having a diameter is screwed into the corresponding surface 10, and one end of a substantially semicircular boosting member 11 whose center portion is supported by the end of the shoe 5 via a pin 13 contacts the corresponding surface 10. The other end of the force member 11 is in contact with a contact portion 12 provided near the base end of the first fixing portion 2 .

The booster member 11 is supported by the shoe 5 at two locations. That is, the bolt/nut 14 is connected to the bolt/nut 14 at one location through the pin 13 and at the other location through the elongated hole 16 provided in the shoe 5.
They are each supported by

Further, the bolt/nut 14 and the elongated length 16 substantially perpendicular to the expansion direction of the shoe 5 enable expansion/contraction of the shoe 5 and rotation of the boosting member 11. The anti-piston sides of the hydraulic cylinder 4 and the shoe 5 are defined by a concave or convex arc (not shown) formed at the end of the shoe 5 and a corresponding convex or concave arc (not shown) on the hydraulic cylinder 4 side. (not shown) are rotatably supported by an engaging portion 17 that is fitted into each other.

This engaging portion 17 will be explained with reference to the embodiment shown in FIGS. 3 and 4.

The half-moon-shaped convex member 18 is inserted into a U groove 4' provided on the side opposite to the piston of the hydraulic cylinder 4 and is attached with a bolt 19. The convex member 18 is tightened by the bolt 19.
Since it can be loosened, the mounting position relative to the U groove 4 is variable.

On the other hand, a recess 20 into which the convex member 18 fits is formed at the end of the shoe 5 . The U groove 4' may be provided directly on the first fixing part 2 of the fixing member 10, and the protruding member 18 and the recess 20 may be provided on the shoe 5 side, and the protruding member 18 and the recess 20 may be provided on the shoe 5 side. It may be provided at the first fixing part 2, which is a member having a structure, or at the end of the hydraulic cylinder 4 on the side opposite to the piston.

This invention has the above configuration.

Next, its effect will be explained.

When pressure oil is sent to the hydraulic cylinder 4 (actuating device), the piston 9 (actuating element) is projected and the contact surface 10 of the rod 23 is
Move one end of the booster member 11 in the shoe expansion direction via (
rotate).

Therefore, the boosting member 11 rotates with the other end in contact with the contact portion 12 serving as a rotational fulcrum, and the boosting member 11 displaces the shoe 5 in the expansion direction via the pin 13.

At this time, the bolt/nut 14 relatively moves along the elongated hole 16 in order to allow the rotation of the booster member 11. On the other hand, the other end of the shoe 5 is rotatably supported by the engaging portion 17, which engages the convex member 18 and the recessed portion 20 with each other.
Rotate to the 4th side. Acts as a brake or clutch.

Now, when the lining 6 of the shoe 5 wears down, the gap between the inner surface of the drum 24 and the shoe 5 (lining 6) becomes larger, and in order to obtain the same brake and clutch force, the piston 9 of the hydraulic cylinder 4 must be moved between the lining 6 and the inner surface of the drum 24. It is necessary to protrude further by the amount corresponding to the wear, resulting in a delay in brake/clutch operation. Therefore, the position of the rod 23 is adjusted to adjust (reduce) the gap between the shoe 5 and the drum 24. When assembling the shoe 5, positioning with respect to the drum 24 is performed by loosening the bolt 19 and shifting the position of the protruding member 18 by the necessary amount, and then tightening the bolt 19 to fix the position of the protruding member 18.

Since the shoe 5 moves forward and backward with respect to the drum 24 with the engaging portion 17 as the center of rotation, the convex member 18 is adjusted so that the gap between the lining 6 and the drum 24 in the circumferential direction is uniform when the shoe 5 is inserted. If the positioning is performed, the shoes 5 will not come into contact with the drum 24 and drag when not in operation, and the lining 6 will be in good contact with the drum 24 when in operation. In addition, if the lining 6 is worn out and a delay in operation occurs, the position of the rod 23 screwed into the piston 9 can be adjusted.
There is no need to change the position of the convex member 18.

In this embodiment, an example of a drum brake/clutch was explained, which is made up of a pair of arc-shaped shoes placed point-symmetrically in the drum and an actuating device. However, as shown in FIG. An actuating device 26 is provided between opposing adjacent ends of a pair of placed shoes 25, and each shoe 25
Needless to say, the same effect applies to a drum brake/clutch whose other end is rotatable. It is clear that in this case, the number of actuating devices 26 may be either one or two.

As described above, according to the present invention, by attaching the convex member at an appropriate position when assembling the shoe, there is no drag caused by the shoe 5 contacting the drum 24 when the shoe 5 is not in operation, and the lining 6 and the drum 24 are not in contact with each other when the shoe is in operation. 24 does not hit unevenly, it is possible to always obtain a constant brake/clutch force, and even if the molding accuracy of the shoe is poor, the attachment and position of the convex member can be adjusted during assembly, which reduces the precision required for parts during manufacture. This has the effect of making it possible to manufacture brakes and clutches at low cost.

[Brief explanation of the drawing]

Fig. 1 is a partially cutaway front view showing the outline of the device of the present invention;
The figure is a sectional view taken along the line A-A in Figure 1, Figure 3 is a partially cutaway front view of the left half showing details of the device of the present invention, and Figure 4 is a cross-sectional view taken along the line B-B in Figure 3. FIG. 5 is a partially cutaway front view showing another embodiment of the present invention. 1...Fixing member 12...Abutting parts 2, 3...Fixing part 13...Pin 4...Hydraulic cylinder (actuating device) 14... Bolts and nuts 5...
... Shoe 16 ... Elongated hole 6 ... Lining 17 ... Engagement part 7 ... Support part 1
8... Protrusion 8... Retraction spring (actuator) 19... Bolt 9... Piston 2o
...Concavity 10...Abutment surface 23...
... Rod l1 ... Boosting member 24 ... Drum agent patent attorney Saburo Tsuji

Claims (1)

[Scope of Claims] 1) A pair of arc-shaped shoes disposed in a drum, an actuating device having an actuator in contact with one end of the shoes, a rotating engagement portion formed at the other end of the shoes, and a pair of arc-shaped shoes arranged in a drum. In a drum brake/clutch comprising a pullback spring attached to pull back toward the opposite side of the drum and a fixed member to which at least the actuating device is attached, the rotary engagement portion of the shoe has an arc-shaped convex portion or a concave portion. Shoe centering for a drum brake/clutch, characterized in that a member forming a concave portion or a convex portion that engages with the convex portion or concave portion is provided on the fixed member side, and the mounting position of the member relative to the fixed member can be changed. mechanism. 2) The shoe centering mechanism for a drum brake/clutch according to claim 1, wherein the shoes are arranged symmetrically about point K within the drum. 3) The shoe centering mechanism for a drum brake/clutch according to claim 1, wherein the shoes are arranged line-symmetrically within the drum.