CN217736105U

CN217736105U - Hydraulic brake caliper, hydraulic brake and construction machine

Info

Publication number: CN217736105U
Application number: CN202221279656.8U
Authority: CN
Inventors: 李玉海; 邹凤新; 张治国; 王增锋
Original assignee: Caterpillar Inc
Current assignee: Caterpillar Inc
Priority date: 2022-05-25
Filing date: 2022-05-25
Publication date: 2022-11-04
Anticipated expiration: 2032-05-25

Abstract

The present disclosure relates to a hydraulic brake caliper (1) comprising a caliper body (10), a piston chamber (11) arranged in the caliper body and capable of receiving a hydraulic fluid, and a piston (12) mounted in the piston chamber, the outer end of which is connected to a friction plate (3) and which is movable relative to the caliper body under the action of the hydraulic fluid between an extended position and a retracted position, wherein the hydraulic brake caliper further comprises a return mechanism connected to the piston, which return mechanism applies a return force to the piston, which return force moves the piston towards the retracted position. The brake caliper can be completely reset when the brake is released, and the problem that the brake caliper is heated or even fails due to the fact that the friction plate of the brake caliper is slightly clamped with the brake disc is avoided. The disclosure also relates to a hydraulic brake and a construction machine with such a hydraulic brake caliper.

Description

Hydraulic brake caliper, hydraulic brake and construction machine

Technical Field

The present disclosure relates to hydraulic brakes, in particular caliper disc hydraulic brakes. More particularly, the present disclosure relates to a hydraulic brake caliper and a hydraulic brake and a work machine comprising such a hydraulic brake caliper.

Background

A brake refers to a device for applying a torque to a moving (e.g., rotating) component in a direction opposite to its direction or tendency of movement in order to slow or stop the movement of the moving component. In vehicles, such as construction machines, which are common today, it is known to use hydraulic brakes, in particular caliper disc hydraulic brakes. Such brakes may typically include a brake caliper secured to a vehicle frame (e.g., a chassis) and a brake disc secured to a moving component (e.g., a wheel hub) for movement therewith. The brake caliper may include a piston disposed within a piston chamber and having a friction plate attached thereto. When braking is required, a piston in the caliper may be extended by hydraulic pressure to bring the friction plates into contact with the brake disc, thereby restraining movement of a moving member connected to the brake disc by frictional force. When it is desired to release the brake, hydraulic pressure on the piston can be released to retract the piston and move the friction pads away from the brake disc, thereby allowing movement of the moving parts connected to the brake disc.

However, there is a problem that when the hydraulic pressure is released to release the brake, a residual back pressure exists in a piston chamber of the brake caliper of the full hydraulic brake system, so that the piston cannot be completely returned, the friction plate is slightly contacted with the brake disc, the brake caliper generates heat seriously after a long time, and the brake disc is worn.

Disclosure of Invention

The present disclosure is directed to solving the above-mentioned problems of the prior art, and to providing a brake caliper capable of ensuring a complete return of a piston in the caliper, thereby preventing heating and failure caused by an undesired contact of a friction pad with a brake disc.

In one aspect, the present disclosure provides a hydraulic brake caliper, which includes:

-a body of the pliers,

-a piston chamber arranged in the caliper body, the piston chamber being able to receive hydraulic fluid;

-a piston mounted in the piston chamber, the outer end of the piston being connected to a friction plate and being movable relative to the caliper body under the action of hydraulic fluid between an extended position and a retracted position;

wherein the hydraulic brake caliper further comprises a return mechanism associated with the piston, the return mechanism applying a return force to the piston that moves the piston toward the retracted position.

The back pressure of a hydraulic system which is as high as 0.2-0.5MPa and possibly exists in a piston cavity of the brake caliper when the brake is released is eliminated through the resetting mechanism, and the piston in the brake caliper is ensured to be completely returned, so that unexpected contact between a friction plate on the piston of the brake caliper and a brake disc is avoided, and the problem that the brake caliper or the brake disc is possibly heated and damaged due to the contact is effectively solved.

In another aspect, the present disclosure relates to a hydraulic brake comprising a hydraulic brake caliper as described hereinbefore.

In a further aspect, the present disclosure relates to a work machine, such as a wheel loader, having a hydraulic brake caliper or a hydraulic brake as described above.

Drawings

The details of the present disclosure and the advantages thereof may be understood by reference to the following description of specific embodiments with reference to the accompanying drawings. In the drawings:

FIG. 1 is a schematic top view of a hydraulic brake according to a preferred embodiment of the present disclosure;

FIG. 2 is a schematic front view of the brake shown in FIG. 1; and

FIG. 3 isbase:Sub>A cross-sectional view taken along line A-A in FIG. 2, showingbase:Sub>A hydraulic brake caliper according tobase:Sub>A preferred embodiment of the present disclosure.

Detailed Description

The technical solutions of the present disclosure are further specifically described below by way of examples in conjunction with the accompanying drawings, which are intended to explain the general concepts of the present disclosure and should not be interpreted as limiting the present disclosure.

The hydraulic brake of the present disclosure will be described below by taking an example of its application to a construction machine such as a loader. However, it should be understood that the hydraulic brake of the present disclosure may be applied not only in work machines, but also in other types of vehicles, and even more generally in any machine having moving parts that require deceleration. Advantageously, the hydraulic brake is a full hydraulic brake.

Referring to fig. 1, the hydraulic brake of the present disclosure may include a hydraulic caliper 1 and a brake disc 2. The brake disc 2 is removably fixedly mounted on a hub (not shown) of the loader and is rotatable in response to rotation of the hub. The hydraulic brake caliper 1 may be removably fixedly mounted on a frame (not shown) of the loader, such as a chassis, for example on a drive axle of the chassis, and arranged adjacent to and around an edge section of the brake disc 2.

As is generally known, a hydraulic brake may comprise one brake disc 2 and a plurality of hydraulic brake calipers 1 arranged around the circumferential edge of the brake disc 2, for example two hydraulic brake calipers 1 diametrically opposite along the brake disc 2 or three hydraulic brake calipers 1 arranged at angular intervals of 120 °, or the like.

Still referring to fig. 1 in combination with fig. 2, the hydraulic brake caliper 1 may comprise caliper bodies, in particular a first caliper body 10 and a second caliper body 10' that are arranged opposite each other such that an edge section of the brake disc 2 is in the space between them. Pistons, which will be described in detail below, may be arranged in the caliper bodies 10, 10', and friction plates 3, 3' may be mounted on the ends of the pistons facing the brake disc 2. By applying hydraulic pressure to the pistons, the friction plates 3, 3' can be moved towards the brake disc 2 and frictionally contact the brake disc 2, whereby a braking effect is achieved by means of friction. When the brake is to be released, the hydraulic pressure on the piston can be released so that the friction plates 3, 3' connected thereto are moved away from the brake disc 2.

The first and second jaw bodies 10, 10' have the same construction and may be separate parts which are detachably assembled together or may be one-piece parts which are manufactured, for example, by injection molding. The hydraulic brake caliper 1 of the present disclosure will be described below by taking the first caliper body 10 as an example, and the first caliper body 10 will be simply referred to as "caliper body 10". It will be appreciated that the second jaw body 10' may also have the features described in detail below. It will also be understood that the hydraulic brake caliper 1 may also have only one (first or second) caliper body arranged on one side of the brake disc 2.

Referring now to fig. 3, there is shown a cross-sectional view of the caliper body 10 of the hydraulic brake caliper 1 of the present disclosure, with the friction plates 3, 3' visible in fig. 1 omitted.

As shown in fig. 3, the hydraulic brake caliper 1 of the present disclosure may include a piston chamber 11 provided in the caliper body 10, and the piston chamber 11 may communicate with a line of a hydraulic system to receive hydraulic fluid. A piston 12 may be mounted in the piston chamber 11 and is reciprocable relative to the jawset 10 between extended and retracted positions by the action of hydraulic fluid. In the extended position, the end of the piston 12 to which the friction plate 3 (see fig. 1) is connected (i.e., the lower end in fig. 3) is moved away from the caliper body 10 so that the friction plate 3 can contact and rub the brake disc 2 (see fig. 1). In the retracted position, the piston 12 is retracted into the piston chamber 11, so that the friction linings 3 at its ends can be brought out of contact with the brake disks 2.

According to the present disclosure, hydraulic brake caliper 1 may further comprise a return mechanism associated with piston 12, which may apply a return force to said piston 12 to move piston 12 towards the retracted position.

In particular, the return mechanism is arranged in the piston chamber 11 together with the piston 12. Of course, the reset mechanism may be disposed outside the piston chamber 11, for example, on the end surface of the caliper body 10.

In the preferred embodiment shown in fig. 3, two identical piston chambers 11 are provided in the caliper body 10, and each piston chamber 11 is provided with an identical piston 12 and a return mechanism. However, it is understood that the hydraulic brake caliper 1 of the present disclosure may also include only one piston chamber 11 provided in the caliper body 10 and only one piston 12 and a return mechanism provided in the piston chamber 11, or may include more than two piston chambers 11 and pistons 12 and return mechanisms.

According to a preferred embodiment, the return mechanism may be constituted by a compression spring 13. The compression spring 13 may be disposed in the piston chamber 11 and connected at one end to the piston 12 so as to be compressed when the piston 12 moves toward the extended position, thereby generating a restoring force tending to return the piston 12 to its retracted position.

Here, the compression spring 13 may be connected at its ends to the piston 12 by a snap ring 14 embedded in a lateral wall of the piston 12.

According to a preferred embodiment, the return mechanism may further comprise a fixed support 15 for mounting or fixing the compression spring 13.

In this case, the fixed bearing 15 may include a first portion 151 and a second portion 152. The first portion 151 may be disposed in the piston chamber 11 and act as a support for the compression spring 13. Said second portion 152 may extend from the piston chamber 11 beyond the outer surface of the caliper body 10 and may be in the form of a threaded rod, so as to be able to cooperate with the tightening nut 16 and possibly the washer 17, so as to hold the whole fixed support 15 immovably in the caliper body 10.

Preferably, the piston 12 may be in the form of a hollow cylinder, the lateral walls of which cooperate with the inner walls of the caliper body 10 delimiting the piston cavity 11, while the bottom wall thereof forms the end for connecting the friction plates 3.

In this case, as shown in fig. 3, the first portion 151 of the fixed support 15 may advantageously have the form of a cylinder and may be housed in the hollow space of said piston 12. The compression spring 13 may be wound or sleeved on said first portion 151, thereby being located between the outer peripheral surface of the first portion 151 and the inner surface of the lateral wall of the piston 12.

Here, advantageously, the axial (i.e. up-down in fig. 3) dimension of said fixed support 15 and in particular of said first portion 151 may be designed such that the first portion 151 abuts against the inner surface of the bottom wall of the piston 12 when the piston 12 is in the fully retracted state.

It is also advantageous that the end of said first portion 151 adjacent to the bottom wall of the piston 12 may have a flange 153 projecting in the radial direction (left-right direction in fig. 3) to act as a positioning stop for the compression spring 13, thereby firmly and reliably mounting the compression spring 13 on the fixed support 15.

Still advantageously, the interior of said first portion 151 of the fixed support 15 may be provided with through holes or passages, such as the mutually

perpendicular passages

154, 155 visible in fig. 3, for the passage and uniform distribution of the hydraulic fluid in the piston chamber 11.

Still referring to fig. 3, according to a preferred embodiment of the present disclosure, two rectangular sealing rings 18, also referred to as "double rectangular sealing rings" 18, may be provided side by side between the outer circumferential surface of the piston 12 and the inner wall of the caliper body 10 defining the piston cavity 11.

In addition, as is generally known, a sealing collar 19 may be provided at the end of the piston 12 for sealing the piston chamber 11.

INDUSTRIAL APPLICABILITY

The assembly and operation of the hydraulic brake caliper 1 of the present disclosure is explained below.

In assembly, the compression spring 13 can first be slipped onto the first part 151 of the fixed support 15 and the compression spring 13 is held in its position by the stop flange 153. Then, the first portion 151 of the fixed holder 15 with the compression spring 13 may be put into the hollow space of the piston 12, and the end portion (the end away from the stopper flange 153) of the compression spring 13 may be coupled with the piston 12 using the snap ring 14. Next, the double rectangular seal ring 18 is placed in the piston chamber 11, and the piston 12 with the compression spring 13 and the fixed bearing 15 connected thereto are inserted into the piston chamber 11 until the second portion 152 of the fixed bearing 15 is exposed from the outer surface of the caliper body 10. Finally, the fastening nut 16 is screwed onto said second portion 152 to keep the fixed support 15 stationary.

In the hydraulic brake caliper 1 thus assembled, the sealing capacity of the piston chamber 11 is greatly improved due to the provision of the double rectangular sealing ring 18. Even if the piston 12 reciprocates frequently, no foreign matter enters the piston chamber 11 to cause a seal failure.

Of course, the assembly steps of the hydraulic brake caliper 1 of the present disclosure are not limited to the sequence described hereinbefore, but may be adjusted and changed according to the actual circumstances.

In use, when, for example, a driver of the vehicle depresses a brake pedal in order to wish to slow down or stop the vehicle, hydraulic fluid fills the piston chamber 11 of the hydraulic brake caliper 1 such that the piston 12 is moved by hydraulic pressure towards the extended position. Thus, the friction plate 3 connected to the end of the piston 12 may be in frictional contact with the disc 2 to perform a braking function. In the process, the compression spring 13 is compressed due to the movement of the piston 12.

When the driver releases the brake pedal and wishes to release the brake, the hydraulic fluid in the piston chamber 11 of the caliper 1 flows out and the piston 12 moves towards the retracted position, bringing the friction plates 3 out of contact with the brake discs 2. In this process, the compression spring 13 applies a return force to the piston 12 toward the retracted position as a result of restoring the pre-compression state. In this way, the spring force of the compression spring 3 effectively counteracts the pressure generated by the hydraulic system back pressure, thereby ensuring that the piston 12 is fully and completely returned to its initial, i.e. retracted, position.

Although the present general inventive concept has been described in conjunction with embodiments, it will be understood by those skilled in the art that various changes and modifications may be made without departing from the principles and spirit of the general inventive concept.

Claims

1. A hydraulic brake caliper comprising:

-a clamp body having a plurality of clamp bodies,

-a piston chamber (11) arranged in the caliper body, the piston chamber being able to receive hydraulic fluid;

-a piston (12) mounted in the piston chamber, the outer end of the piston being connected to a friction plate (3) and the piston being movable relative to the caliper body between an extended position and a retracted position under the action of hydraulic fluid;

characterised in that the hydraulic brake caliper further comprises a return mechanism associated with the piston and applying a return force to the piston to move the piston towards the retracted position.

2. Hydraulic brake calliper according to claim 1, wherein the return mechanism comprises a compression spring (13) arranged in the piston chamber, one end of the compression spring being connected to the piston (12) so as to be compressed when the piston is moved towards the extended position.

3. Hydraulic brake calliper according to claim 2, wherein the return mechanism further comprises a fixed support (15) fixed to the calliper body, on which the compression spring (13) is mounted.

4. Hydraulic brake calliper according to claim 3, wherein the fixed support (15) comprises a first portion (151) housed in the piston cavity (11) for mounting the compression spring (13) and a second portion (152) projecting from the outer surface of the calliper body, threaded for cooperating with a fastening nut (16).

5. Hydraulic brake caliper according to claim 4, characterized in that the piston (12) has the form of a hollow cylinder, the first portion (151) of the fixed support (15) being seated in the hollow space of the piston and the compression spring (13) being mounted around the first portion so as to be located between the outer peripheral surface of the first portion and the inner surface of the lateral wall of the piston.

6. Hydraulic brake caliper according to claim 5, characterized in that the first portion (151) of the fixed support (15) has a stop flange (153) at the end for positioning a compression spring and internally has a passage (154, 155) for the passage of hydraulic fluid.

7. Hydraulic brake caliper according to one of the claims 2 to 6, characterized in that the compression spring (13) is connected to the piston (12) by means of a snap ring (14).

8. Hydraulic brake calliper according to any of claims 1-6, wherein two piston chambers (11) are provided in the calliper body, each piston chamber having a piston (12) and a return mechanism mounted therein.

9. Hydraulic brake caliper according to one of the claims 1 to 6, characterised in that a double rectangular sealing ring (18) cooperating with the outer circumferential surface of the piston (12) is arranged in the piston chamber (11).

10. Hydraulic brake caliper according to one of the claims 1 to 6, characterized in that the caliper body comprises a first caliper body (10) and a second caliper body (10') arranged opposite each other, each provided with a respective piston chamber (11), piston (12) and return means.

11. A hydraulic brake, characterized in that it comprises a hydraulic brake caliper according to one of claims 1 to 10.

12. A working machine, characterized in that it comprises a hydraulic brake caliper according to one of claims 1-10 or a hydraulic brake according to claim 11.