JP2686181B2 - Reverse-acting disc brake device - Google Patents

Abstract

PURPOSE:To facilitate exchange of a pad of an inverse actuation disc brake device, which maintains constant the stroke of a lever to rotate a cam, by opening with a cam a pair of carries, which press a friction pad against a disc while constantly receiving the strength of a pressurized means, and thereby releasing the brake, and also providing an automatic adjusting device for pad abrasion. CONSTITUTION:A means to restore the position of a carrier is composed by providing a screw hole 17 on a housing 11 fixed to a carrier 2 and screwing a return bolt 18 into the screw hole 17. When the return bolt 18 is turned after making it contact the rear end of an adjusting bolt 12 with a clutch 15 in a disengaged state as shown in the drawing, an adjusting bolt 13 or an abrasion adjusting device turning into a reaction force supporting member and the housing into a propulsion transmission member, cause the carrier 2 to open as the adjusting bolt 12 turns and, simultaneously, the relative positions of the adjusting bolt 12 and the carrier 2 are restored to their original positions, thus the pad can be exchanged without releasing the strength of the pressurized means which constantly applies the closing force to the carrier.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a reverse operation disc brake device having a carrier position restoring mechanism for facilitating replacement of a friction pad (hereinafter simply referred to as a pad).

[0002]

2. Description of the Related Art Among mechanical reverse actuated disc brake devices used in forklift trucks and the like, the following, that is, as shown in FIGS. 3 and 4, a pair of pads 3, 3 for holding a disc D between them. Is supported by a pair of carriers 2, 2 which can be opened and closed with a hinge point at one end as a fulcrum, and the other end of the carrier is provided with a pressurizing means 4 (a spring is shown in the figure) for constantly applying a closing force to the pair of carriers. Some are provided with a cam 5 that pushes out the pair of carriers against the force of the means. The cam 5 rotates by pulling a lever 6 having a return spring 7. 1 is a bracket for supporting the carrier.

This device has already been filed by the present applicant in Japanese Patent Application No. 2-3.
As suggested in No. 08240, even if the pad 3 is worn
The function of the pad wear automatic adjustment mechanism 10, which will be described later, causes
The stroke of lever 6 to release the rake is always
With a reverse-acting disc brake device that is designed to be kept constant
is there.

In the mechanism 10, as shown in FIG. 2, a housing 11 is fixed to a carrier 2 and an adjusting bolt 12 having a multiple thread is screwed into the housing to connect the bolt and the shaft portion 5a of the cam 5 . Between the push rod 13 and its
Flange 14 with push rod 13 slidably inserted
And when the flange 14 is pushed by the cam 5 between the flange 14 and the bolt 12 ( this state is shown in FIG.
Enlarged shown), namely be those provided clutch 15 to stop the rotation of the engaging bolts 12 at the time of brake release, when the cam 5 is in the braking position (this state
6 is enlarged ), the movement of the bolt 12 to the disc side does not occur on the cam surface of the cam 5 via the push rod 13.
The shaft 5a prevents the cam 5 from releasing the pressing force.
The flange 14 that is
The clutch 15 is released. Therefore, if the pad wears, the bolt 12 rotates and the carrier 2 always moves to a position where the wear amount is compensated.

On the other hand, when the cam is rotated to release the brake, the clutch 15 is applied to stop the rotation of the bolt 12 and the pushing back force of the cam is transmitted to the carrier as it is, and the carrier 2 is pushed back from the brake operating position by a certain amount.

[0006]

In the above-described reverse-acting disc brake device, the pad 3 cannot be replaced unless the nut 8 is loosened to completely release the closing force of the carrier by the pressing means 4. Although full worn pad can be detached to release the brake with cam 5, new pads that carrier 2 and Di and returns the carrier 2 to the original position
Secure a space more than the thickness of the new pad with the disk D
This is because it cannot be installed without it.

An object of the present invention is to solve such a problem and to facilitate the pad replacement work.

[0008]

SUMMARY OF THE INVENTION In a reverse-acting disc brake device of the present invention, a housing of a pad wear automatic adjusting mechanism fixed to a carrier is provided with a screw hole, and the screw hole is returned to make point contact with the rear end of the adjusting bolt. It is characterized in that a carrier position restoring mechanism is constructed by screwing the use bolts, and when the carrier is returned to the original position by this mechanism, the adjusting bolt is also returned at the same time.

[0009]

When the return bolt is rotated in the screwing direction while the adjusting bolt is received by the shaft of the cam via the push rod, the adjusting bolt receives the reaction force receiving member and the housing receives the thrust transmitting member. Then, a force acts on the carrier to pull it back against the force of the pressing means. At this time, the clutch that restricts the rotation of the adjustment bolt is disengaged. Therefore, when the return bolt is rotated, the adjusting bolt is also rotated by the force applied to the carrier, whereby the carrier is gradually spread and returned to the original position. Further, since the adjusting bolt remains in the original position during this time, the relative position with respect to the carrier changes, and thereby the return of the adjusting bolt is completed at the same time.

[0010]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS FIG. 1 shows the essential parts of a brake system according to an embodiment. The same reference numerals as those in FIG. 2 indicate the same elements, and thus re-explanation is omitted. As shown in the drawing, a screw hole 17 is provided in the rear portion of the housing 11. The screw of this hole is preferably a fine screw that requires a small operating force. Further, it is desirable that the entrance of this hole 17 is usually sealed with a rubber cap 16 as shown in FIG. 2 in order to prevent the intrusion of dust and water.

When replacing the pad, the rubber cap is pulled out and a return bolt 18 having a rounded tip is screwed into the screw hole 17, and the bolt 18 is screwed in at a position where the tip is in contact with the rear end of the adjusting bolt 12 as shown in the figure. Rotate further in the direction. Adjust bolt 12 is push rod 1
It is received by the shaft portion 5a of the cam 5 via 3 and does not move further toward the cam side. However, the push rod in this state
A relative displacement occurs between the clutch 3 and the flange 14 and the clutch 15
The adjustment bolt 12 is allowed to rotate because it is disengaged. Therefore, when the return bolt 18 is further rotated from the position shown in the drawing, the housing 11 rotates the adjustment bolt 12 and gradually separates from the cam, and pushes the carrier 2 toward the original position.

When the carrier 2 is thus spread out until it becomes substantially parallel to the disk, the worn pad 3 is removed and a new pad is set. After that, when the return bolt 18 is loosened and pulled out, the positional relationship between the carrier 2 and the adjustment bolt 12 is also returned to the original state by the carrier return, so that the pad wear automatic adjusting mechanism normally operates and the pad 3 is not released. It is pressed against the disc by the force of the pressing means (4 in FIG. 3).

When the nut 8 shown in FIG. 3 is tightened according to the wear of the pad, the nut is loosened by an amount corresponding to the tightening amount from the original position so that the force of the pressurizing means is returned to the original size. Need to bring back.

[0014]

As described above, according to the present invention,
The restoration mechanism, which is constructed by additionally installing screw holes and return bolts, allows the carrier and the adjust bolt to return to their original positions at the same time without releasing the closing force applied to the carrier, making pad replacement work easy. The effect is obtained.

[Brief description of the drawings]

FIG. 1 is a sectional view showing a main part of an embodiment.

FIG. 2 is a sectional view of the previously proposed pad wear automatic adjustment mechanism.

FIG. 3 is a plan view of a reverse-acting disc brake including the wear adjusting mechanism of FIG.

FIG. 4 is a side view of the same brake.

FIG. 5 (a) Brake release of automatic pad wear adjustment mechanism
State when brake release when the plan view state enlarged showing (b) pad wear automatic adjustment mechanism
Enlarged sectional view

FIG. 6 (a) Brake operation of pad wear automatic adjustment mechanism
State during braking when the plan view state enlarged showing (b) pad wear automatic adjustment mechanism
Enlarged sectional view

[Explanation of symbols]

1 bracket 2 carrier 3 pad 4 pressurizing means 5 cam 5a shaft part 6 lever 7 return spring 8 nut 10 pad wear automatic adjustment mechanism 11 housing 12 adjust bolt 13 push rod 14 flange 15 clutch 16 rubber cap 17 screw hole 18 return bolt

Claims (1)

(57) [Claims] 1. A friction pad for sandwiching a disk, a pair of carriers for supporting the pad, a pressing means for constantly applying a closing force to the carrier, and a cam for spreading the pair of carriers against the force of the pressing means. It has, and a housing fixed to the carrier, the adjusting bolt of the multiple thread stopping in the axial portion of the cam through the push rod to move to the disk side is screwed to the housing, this Ajasutobo
Installed between the cam and the cam and slide the push rod.
A flange that is freely inserted, and this flange and the
It is provided between the cast bolt and the flange, and the flange is
In a reverse-acting disc brake device having an automatic pad wear adjusting mechanism, which comprises a clutch that engages when it is pushed and moved to stop rotation of an adjusting bolt, a screw hole is provided in the housing, and the adjusting screw is provided in the screw hole. A reverse-acting disc brake device, characterized in that a restoring bolt that makes point contact with the rear end of the bolt is screwed into a carrier position restoring mechanism.