CN215908291U

CN215908291U - Brake clearance automatic adjusting mechanism of full disc brake

Info

Publication number: CN215908291U
Application number: CN202121929768.9U
Authority: CN
Inventors: 张云科; 张永杰; 李瑞栋; 郭海广; 其他发明人请求不公开姓名
Original assignee: Hebei Exxon Power Technology Co ltd
Current assignee: Hebei Weikete Machinery Technology Co ltd
Priority date: 2021-08-17
Filing date: 2021-08-17
Publication date: 2022-02-25
Anticipated expiration: 2031-08-17

Abstract

The utility model provides an automatic brake clearance adjusting mechanism of a full-disc brake, wherein the full-disc brake comprises a brake disc, a thrust frame and a ramp gear, wherein the ramp gear pushes the thrust frame to move towards the brake disc through an ejector rod, so that a friction plate on one side of the brake disc on the thrust frame and a friction plate on the other side of the brake disc clamp the brake disc together to generate braking; the automatic adjusting mechanism comprises an air chamber, an automatic adjusting arm, an input shaft and a ramp gear, wherein the input shaft is used for driving the ramp gear to rotate, the input shaft is of a gear shaft structure, a spline connecting part is arranged at one end, connected with the automatic adjusting arm, of the input shaft, and a gear connecting part is arranged at one end, connected with the ramp gear, of the input shaft. The utility model applies the automatic adjusting arm to the full-disc brake to realize the automatic clearance adjustment by means of the mature adjusting principle of the drum type automatic adjusting arm and the cam shaft, thereby greatly improving the safety of the full-disc brake for vehicle braking.

Description

Brake clearance automatic adjusting mechanism of full disc brake

Technical Field

The utility model relates to a vehicle brake, in particular to an automatic brake clearance adjusting mechanism of an all-disc brake.

Background

The automobile brake is a braking device of an automobile, and the brakes used by the automobile are almost all of friction type and can be divided into drum type and disc type. The rotary element in the drum brake friction pair is a brake drum, and the working surface of the rotary element is a cylindrical surface; the rotating element of the disc brake is then a rotating brake disc, with the end face being the working surface. Generally, an air pressure drum brake is used for braking in a vehicle, in the running process of the vehicle, a brake drum and a friction plate are not directly attached together, but a certain gap exists, the gap is a brake gap, the brake gap is used for ensuring the normal running of a wheel, along with the abrasion of the friction plate of a braking device in the using process, the gap between the brake drum and the friction plate can be gradually increased, the gap exceeds the initially set brake gap, the exceeding part is an excessive brake gap, the excessive brake gap causes the stroke of a brake air chamber ejector rod to be lengthened, the brake time is further prolonged, in severe cases, the brake lag or even failure is easily caused, and the safety of the vehicle and personnel can be damaged.

At present, some drum brakes are provided with an automatic brake clearance adjusting arm for automatically adjusting the brake clearance of the drum brake to be maintained in the vicinity of the initially set brake clearance, so that the braking force of the vehicle is in a favorable state. The brake clearance of the current common automatic brake clearance adjusting arm is usually adjusted through a worm and gear transmission structure. Fig. 1 is a schematic structural view of an automatic brake clearance compensating device of a drum brake in the prior art. Fig. 2 is an exploded view of an automatic brake clearance adjusting arm 20 of a drum brake according to the prior art. Fig. 3 is a schematic structural diagram of a camshaft in the prior art, in which one end of the camshaft is a spline shaft connected with an automatic adjusting arm, and the other end of the camshaft is a cam for adjusting a brake shoe. At present, the condition that the vehicle or the heavy-duty vehicle uses the full-disc brake is rare, the arranged automatic brake clearance compensation device is less or a special automatic brake clearance compensation device is arranged, and the full-disc brake clearance compensation device cannot be commonly used with an automatic adjusting arm of a drum brake, so that the maintenance and the like of an adjusting mechanism of the vehicle brake are extremely inconvenient.

Therefore, it is particularly important to provide an automatic brake clearance adjusting device for an all-disc brake, and to provide versatility with an automatic adjusting arm of a drum brake.

SUMMERY OF THE UTILITY MODEL

In view of the above, embodiments of the present invention provide an automatic brake clearance adjusting mechanism for an all-disc brake, so as to obviate or mitigate one or more of the disadvantages of the related art.

The technical scheme of the utility model is as follows:

the full-disc brake comprises a brake disc and a thrust frame, and the automatic adjusting mechanism comprises an air chamber, an automatic adjusting arm, an input shaft and a ramp gear; the input shaft is used for driving the ramp gear to rotate, the ramp gear pushes the thrust frame to move towards the brake disc through the ejector rod, and the friction plate on one side of the brake disc on the thrust frame and the friction plate on the other side of the brake disc clamp the brake disc together to generate braking; the input shaft is of a gear shaft structure, a spline connecting part is arranged at one end, connected with the automatic adjusting arm, of the input shaft, and a gear connecting part is arranged at one end, connected with the ramp gear, of the input shaft.

Preferably, the tooth-shaped structure of the gear connecting part is helical teeth or straight teeth.

Preferably, the gear connection has a first shaft section and a first shoulder on a side adjacent to the spline connection for mounting a bearing; the gear connecting part is provided with a second shaft section and a second shaft shoulder at one side far away from the spline connecting part so as to install a bearing.

Preferably, the first shaft section has a larger shaft diameter than the second shaft section.

Preferably, the length of the spline connection is greater than the length of the spline in the turbine of the automatic adjustment arm.

Preferably, the spline connecting part is provided with a groove on the outer side for installing the clamp spring and realizing the axial fixation of the input shaft.

Preferably, the body of the input shaft, the spline connection portion and the gear connection portion are integrally formed.

Preferably, the spline connecting part is a rectangular spline or an involute spline.

Preferably, the tooth-shaped structure of the gear connecting part is helical teeth, and the helical angle of the helical teeth is 20-30 degrees.

Preferably, both ends of the input shaft have a chamfered structure.

According to the automatic brake clearance adjusting mechanism of the full-disc brake, the technical effects at least comprising the following steps are achieved:

(1) the utility model applies the automatic adjusting arm to the full-disc brake to automatically adjust the clearance by means of the mature adjusting principle of the drum type automatic adjusting arm and the cam shaft, thereby greatly improving the safety of the full-disc brake for vehicle braking. During braking, the automatic adjusting arm and the input shaft can enable the clearance between the friction plate and the brake disc to be constant (preset value), so that the braking force output of all wheels of the vehicle is more stable, and the vehicle can run more safely.

(2) The automatic brake clearance adjusting mechanism of the full-disc brake can use a universal automatic adjusting arm without a special automatic brake clearance compensating device, so that the automatic brake clearance adjusting mechanism has high interchangeability and economy, and is greatly convenient for the maintenance of the full-disc brake of a vehicle.

Additional advantages, objects, and features of the utility model will be set forth in part in the description which follows and in part will become apparent to those having ordinary skill in the art upon examination of the following or may be learned from practice of the utility model. The objectives and other advantages of the utility model will be realized and attained by the structure particularly pointed out in the written description and claims hereof as well as the appended drawings.

It will be appreciated by those skilled in the art that the objects and advantages that can be achieved with the present invention are not limited to the specific details set forth above, and that these and other objects that can be achieved with the present invention will be more clearly understood from the detailed description that follows.

Drawings

The accompanying drawings, which are included to provide a further understanding of the utility model and are incorporated in and constitute a part of this application, illustrate embodiment(s) of the utility model and together with the description serve to explain the principles of the utility model. The components in the figures are not necessarily to scale, emphasis instead being placed upon illustrating the principles of the utility model. For purposes of illustrating and describing some portions of the present invention, corresponding parts of the drawings may be exaggerated, i.e., may be larger, relative to other components in an exemplary apparatus actually manufactured according to the present invention. In the drawings:

fig. 1 is a schematic structural view of an automatic brake clearance compensating device of a drum brake in the prior art.

Fig. 2 is an exploded view of an automatic brake clearance adjusting arm of a drum brake according to the prior art.

Fig. 3 is a schematic structural view of a camshaft of a drum brake in the related art.

Fig. 4 is an exploded view of a prior art full disc brake.

Fig. 5 is a schematic diagram of a driving structure of an all-disc brake in the prior art.

Fig. 6 is a schematic structural diagram of an input shaft according to an embodiment of the utility model.

Fig. 7 is a partial structural schematic view of an automatic braking clearance adjusting mechanism of an all-disc brake according to an embodiment of the present invention.

Reference numerals:

400. an input shaft; 410. a spline connection portion; 420. a gear connecting portion; 401. a first shaft section; 402. a second shaft section; 421. a first shoulder; 422. a second shoulder; 403. a groove;

Detailed Description

In order to make the objects, technical solutions and advantages of the present invention more apparent, the present invention will be described in further detail with reference to the following embodiments and accompanying drawings. The exemplary embodiments and descriptions of the present invention are provided to explain the present invention, but not to limit the present invention.

It should be noted that, in order to avoid obscuring the present invention with unnecessary details, only the structures and/or processing steps closely related to the scheme according to the present invention are shown in the drawings, and other details not so relevant to the present invention are omitted.

It should be emphasized that the term "comprises/comprising" when used herein, is taken to specify the presence of stated features, elements, steps or components, but does not preclude the presence or addition of one or more other features, elements, steps or components.

It is also noted herein that the term "coupled," if not specifically stated, may refer herein to not only a direct connection, but also an indirect connection in which an intermediate is present.

Hereinafter, embodiments of the present invention will be described with reference to the accompanying drawings. In the drawings, the same reference numerals denote the same or similar parts, or the same or similar steps.

As shown in fig. 1, a drum brake of the related art generally employs a structure including an air chamber 10, a brake clearance automatic adjusting arm 20 connected to the air chamber, a cam shaft connected to the brake clearance automatic adjusting arm 20, and the like. The camshaft is embodied as an S-shaped camshaft and comprises a cam and an S shaft. The camshaft may be mounted to the axle by rollers. In fig. 1, an air chamber 10 is connected to a rotating arm of an automatic brake clearance adjusting arm 20, the rotating arm is provided with a connecting hole connected to the air chamber 10, and a cam shaft is connected to the center of the automatic brake clearance adjusting arm 20 through a spline. When the vehicle needs to be braked, the push rod of the air chamber 10 extends out to drive the automatic brake clearance adjusting arm 20 to rotate around the central axis thereof, the cam shaft rotates along with the automatic brake clearance adjusting arm 20, and the cam shaft pushes away a brake shoe (not shown in the figure) in the rotating process, so that a friction plate and a brake drum of the brake shoe are mutually rubbed to promote the vehicle to decelerate.

The automatic brake clearance adjusting arm 20 may be an automatic brake clearance adjusting arm of the prior art, and as shown in fig. 2 and 3, a cylindrical cavity is formed in the middle of a housing of the automatic brake clearance adjusting arm, a one-way clutch, a worm and a spring are sequentially arranged along the axial direction of the cylindrical cavity, the spring is pre-compressed between the tail of the worm and the housing to provide elastic force for the engagement of the worm with the one-way clutch, and the head of the worm and a bevel gear of the one-way clutch may be engaged to be engaged or moved in the axial direction to be disengaged from the one-way clutch. The lower part of the shell is inserted with a turbine, the axis of the turbine is the rotation axis of the brake clearance automatic adjusting arm, and the S shaft of the camshaft is connected with the center hole of the turbine through a spline. Braking clearance automatic adjustment arm 20 still includes parts such as fixing base, rack, and the fixing base is located the outside of turbine, and the fixing base is equipped with and rack complex breach, and the rack is at the braking and is relieved in-process breach conflict upper end, lower extreme to in good time drive one-way clutch, gear revolve, drive one-way clutch and rotate. When braking, the worm wheel is subjected to the reaction force of the brake drum, the acting force abutting against the spring is applied to the worm, when braking is released, the acting force applied by the worm wheel is released, the spring pushes the worm to be connected with the one-way clutch, the rack drives the one-way clutch to rotate, the worm is driven to rotate, then the worm wheel and the cam shaft are driven to rotate for a certain angle, and therefore excessive braking gaps are automatically eliminated. The principle of the turbine, the worm and the one-way clutch for automatically adjusting the brake clearance is the prior art, and is not described in detail herein.

The utility model provides an automatic brake clearance adjusting mechanism of an all-disc brake. As shown in fig. 4, in an embodiment of the prior art, the full disc brake may include a driving device, a transmission device, a brake disc 600, friction plates, a case, and the like. Wherein the case body may include the case housing 200, the cover plate 240, and the outer cover 700 arranged in the axial direction of the brake disc 600. Wherein the housing 200 is used to mount the transmission, the cover 240 is used to cover the housing 200 and attach the brake to the axle flange, and the outer cover 700 is used to cover the brake disc 600. The housing 200 and the outer cover 700 serve primarily as housings for the brake of the present invention, and the cover 240 is interposed between the housing 200 and the outer cover 700 for enclosing a portion of the actuator within the housing 200 and mounting the brake to the axle flange.

The transmission device of the full-disc brake can adopt the principles of gear transmission and screw transmission to convert circular motion into linear motion of the friction plate so as to generate braking torque. Specifically, friction plates are disposed on both sides of the brake disc, and may include dynamic friction plates 810 and static friction plates 820. The transmission means may include an input shaft 400, a ramp gear 300, a jack 100, and the like. The ramp gear 300 is a ring gear with partial internal teeth, and the input shaft 400 and the ring gear are internally meshed. The outer peripheral surface of the ramp gear 300 is provided with a plurality of spiral ramps, the ejector rod 100 is arranged at the ramps, under the limiting action of the limiting hole of the cover plate 240, the ejector rod 100 moves along a straight line and pushes the thrust frame 500 to be close to the brake disc 600, the dynamic friction plate 810 is pushed to be pressed against one end of the brake disc 600, the brake disc 600 slides in the axial direction of the outer hub in a small displacement mode and is pressed with the friction plates on the two sides of the brake disc 600, and therefore braking torque is generated. The full-disc brake applies a ramp boosting principle, a spiral slope surface is arranged on the circumferential surface of a ramp gear, the rotary motion of the ramp gear is converted into linear motion, and multiple boosting can be realized through the transmission device. Wherein, the ramp gear 300 pushes the thrust frame 500 to move towards the brake disc 600 through the push rod 100, so that the friction plate 810 on one side of the brake disc on the thrust frame 500 and the friction plate 820 on the other side of the brake disc clamp the brake disc together to generate braking.

In the driving structure diagram of the full-disc brake as shown in fig. 5, the ram 11 of the air chamber 10 is connected to the input shaft 400 of the present invention through the connecting rod 12, wherein the ram 11 and the connecting rod 12 can form a crank-rocker mechanism, and the air chamber ram 11 is used as a rocker, and the reciprocating swing of the rocker is converted into the rotation of a crank. The input shaft 400 and the connecting rod 12 can be connected through a transmission shaft, and the connection form can be a coupling or a key connection. The boosting execution device is additionally arranged between the braking force source and the brake disc of the full-disc brake, so that the braking force can be increased, and the braking effect is enhanced.

However, the full-disc brake is not provided with an automatic adjusting arm, and the gap between the friction plate and the brake disc cannot be automatically adjusted. The utility model discloses an automatic adjusting mechanism for a brake clearance of a full-disc brake, which is designed in order to ensure that the clearance between a friction plate and a brake disc is always in a constant size and the brake force output of all wheels is more stable.

As shown in fig. 7 and 4, the automatic adjustment mechanism of the embodiment of the present invention also includes an air cell 10, an automatic adjustment arm 20, an input shaft 400, and a ramp gear 300. Wherein, the input shaft 400 is used for driving the ramp gear 300 to rotate. The input shaft 400 of the embodiment of the present invention has a gear shaft structure, one end of the input shaft 400 connected to the automatic adjustment arm 20 has a spline connection portion 410, and one end of the input shaft 400 connected to the ramp gear 300 has a gear connection portion 420. The input shaft 400 has a spline connection portion 410 at one end thereof and is capable of being connected to an automatic adjusting arm 20 commonly used in a drum brake in the related art, and a gear connection portion 420 at the other end thereof and is capable of being connected to an all-disc brake with a ramp gear 300 according to an embodiment of the present invention, so that the automatic adjusting arm can be suitably used in an all-disc brake.

The utility model applies the automatic adjusting arm to the full-disc brake to realize the automatic clearance adjustment by means of the mature adjusting principle of the drum type automatic adjusting arm and the cam shaft, thereby greatly improving the safety of the full-disc brake for vehicle braking.

The automatic brake clearance adjusting mechanism of the full-disc brake can use a universal automatic adjusting arm without a special automatic brake clearance compensating device, so that the automatic brake clearance adjusting mechanism has high interchangeability and economy, and is greatly convenient for the maintenance of the full-disc brake of a vehicle.

Preferably, the tooth-shaped structure of the gear connecting part 420 is helical teeth or straight teeth. Further preferably, the tooth-shaped structure of the gear connecting portion 420 is helical teeth, and the helix angle thereof is 20 ° to 30 °, for example, 25 ° may be preferable. The helical teeth have larger bearing capacity than straight teeth, more stable transmission, good meshing performance and compact structure, and are suitable for high-speed heavy load conditions.

Preferably, the gear connection portion 420 has a first shaft section 401 and a first shoulder 421 at a side near the spline connection portion 410 to mount a bearing; the gear connection 420 has a second shaft section 402 and a second shoulder 422 on the side remote from the spline connection 410 for mounting a bearing. Two bearings are installed in the base housing 100 at both sides of the gear connecting part 420 of the input shaft 400, so that the transmission process is smooth. The two bearings installed at the first shoulder 421 and the second shoulder 422, respectively, are different in size to facilitate the assembling process.

In some embodiments, the length of the splined portion 410 is greater than the length of the splines in the turbine of the automatic adjustment arm, such that relative axial slippage can occur at the connection of the input shaft 400 to the automatic adjustment arm. When the vehicle is braked, the air chamber push rod pushes the automatic adjusting arm, and the automatic adjusting arm converts the output force into positive thrust through the gear connecting part 420 of the input shaft 400 and the ramp gear, so that the vehicle is braked. When the brake is released, the air chamber and the automatic adjusting arm can be restored to the initial position under the pulling of the return spring. Since the rotation angle of the automatic adjustment arm is preset, when the clearance between the friction plate and the brake disc is too large, the rotation angle of the automatic adjustment arm increases, and at this time, the automatic adjustment arm will dial the input shaft 400 forward (in the direction close to the brake disc), so that the clearance is kept constant.

Preferably, the spline connection portion 410 has a groove 403 on the outer side for installing a clamp spring and achieving axial fixing of the automatic adjusting arm, that is, fixing the automatic adjusting arm on the input shaft 400.

Further, the spline connection portion 410 is a rectangular spline or an involute spline. Preferably, spline connection 410 is an involute spline. The involute spline has the advantages of multiple tooth numbers, thick tooth root at the tooth end, strong bearing capacity, easy automatic centering, high installation precision and the like. Under the same external dimension, the involute spline has a larger small diameter, which is beneficial to increasing the rigidity of the shaft.

Preferably, both ends of the input shaft 400 have a chamfered structure for facilitating the installation of parts on the shaft.

Features that are described and/or illustrated with respect to one embodiment may be used in the same way or in a similar way in one or more other embodiments and/or in combination with or instead of the features of the other embodiments in the present invention.

The above description is only a preferred embodiment of the present invention, and is not intended to limit the present invention, and various modifications and changes may be made to the embodiment of the present invention by those skilled in the art. Any modification, equivalent replacement, or improvement made within the spirit and principle of the present invention should be included in the protection scope of the present invention.

Claims

1. A brake clearance automatic adjusting mechanism of an all-disc brake comprises a brake disc and a thrust frame, and comprises an air chamber, an automatic adjusting arm, an input shaft and a ramp gear; the input shaft is used for driving the ramp gear to rotate, the ramp gear pushes the thrust frame to move towards the brake disc through the ejector rod, and the friction plate on one side of the brake disc on the thrust frame and the friction plate on the other side of the brake disc clamp the brake disc together to generate braking; it is characterized in that the preparation method is characterized in that,

the input shaft is of a gear shaft structure, a spline connecting part is arranged at one end, connected with the automatic adjusting arm, of the input shaft, and a gear connecting part is arranged at one end, connected with the ramp gear, of the input shaft.

2. The automatic brake clearance adjusting mechanism of an all-disc brake according to claim 1, wherein the tooth-shaped structure of the gear connecting portion is helical teeth or straight teeth.

3. The automatic brake clearance adjusting mechanism for an all-disc brake according to claim 2, wherein the gear connecting portion has a first shaft section and a first shoulder on a side close to the spline connecting portion to mount a bearing; the gear connecting part is provided with a second shaft section and a second shaft shoulder at one side far away from the spline connecting part so as to install a bearing.

4. The automatic brake clearance adjustment mechanism for an all-disc brake according to claim 3, wherein the first shaft section has a larger shaft diameter than the second shaft section.

5. The automatic brake clearance adjusting mechanism of an all-disc brake according to claim 1 or 2, wherein the length of the spline connection portion is greater than the length of a spline in a turbine of an automatic adjusting arm.

6. The automatic brake clearance adjusting mechanism of an all-disc brake according to claim 5, wherein the spline connecting portion has a groove on the outer side for mounting a clamp spring and achieving axial fixation of the input shaft.

7. The automatic brake clearance adjusting mechanism of an all-disc brake according to claim 5, wherein the body of the input shaft, the spline connection portion, and the gear connection portion are integrally formed.

8. The automatic brake clearance adjusting mechanism of an all-disc brake according to claim 5, wherein the spline connecting portion is a rectangular spline or an involute spline.

9. The automatic brake clearance adjusting mechanism for an all-disc brake according to claim 1, wherein the tooth-shaped structure of the gear connecting portion is helical teeth, and the helix angle thereof is 20 ° to 30 °.

10. The automatic brake clearance adjusting mechanism of an all-disc brake according to claim 3 or 4, wherein both ends of the input shaft have a chamfered structure.