CN220302596U - Brake with variable braking force - Google Patents

Brake with variable braking force Download PDF

Info

Publication number
CN220302596U
CN220302596U CN202322100691.XU CN202322100691U CN220302596U CN 220302596 U CN220302596 U CN 220302596U CN 202322100691 U CN202322100691 U CN 202322100691U CN 220302596 U CN220302596 U CN 220302596U
Authority
CN
China
Prior art keywords
brake
piston
oil inlet
cavity
braking force
Prior art date
Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
Active
Application number
CN202322100691.XU
Other languages
Chinese (zh)
Inventor
史玉红
覃涛
邓霄荣
申佳佳
林月芳
张庚昊
曹久刚
王叶
Current Assignee (The listed assignees may be inaccurate. Google has not performed a legal analysis and makes no representation or warranty as to the accuracy of the list.)
Biboster Beijing Automotive Technology Co ltd
Original Assignee
Biboster Beijing Automotive Technology Co ltd
Priority date (The priority date is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the date listed.)
Filing date
Publication date
Application filed by Biboster Beijing Automotive Technology Co ltd filed Critical Biboster Beijing Automotive Technology Co ltd
Priority to CN202322100691.XU priority Critical patent/CN220302596U/en
Application granted granted Critical
Publication of CN220302596U publication Critical patent/CN220302596U/en
Active legal-status Critical Current
Anticipated expiration legal-status Critical

Links

Landscapes

  • Braking Arrangements (AREA)

Abstract

The utility model discloses a brake with variable braking force, which comprises the following steps: the brake caliper and the brake disc are fixedly connected to the hub of the vehicle, and the brake caliper can float across two sides of the brake disc; a first hydraulic cavity, a second hydraulic cavity, a first oil inlet and a second oil inlet are formed in one side of the brake caliper, wherein the first oil inlet is communicated with the first hydraulic cavity, and the second oil inlet is communicated with the second hydraulic cavity; the spring is arranged in the first hydraulic cavity, one end of the spring is propped against the end part of the first hydraulic cavity, which is far away from the first oil inlet, a first piston with an I-shaped section is inserted in the cavity of the spring, one end of the first piston, which is far away from the first oil inlet, is a first hollow cavity with a first cross-sectional area, the other end of the first piston, which is close to the first oil inlet, is a second hollow cavity with a second cross-sectional area, and the other end of the spring is propped against the end part of the second hollow cavity, which is far away from the first oil inlet; wherein the first cross-sectional area is smaller in value than the second cross-sectional area.

Description

Brake with variable braking force
Technical Field
The utility model relates to the technical field of brakes, in particular to a brake with variable braking force.
Background
The disc brake mainly comprises a brake disc, a slave cylinder, a brake caliper, an oil pipe and other parts, and is an important component in a brake system device. Wherein the brake disc is made of alloy steel and is fixed on the wheel, and rotates along with the wheel, braking force is generated through interaction between a brake caliper and the brake disc, the brake caliper is usually fixed on the frame of the vehicle, and the brake disc is fixed on the wheel. The brake caliper includes a piston and a brake pad that slide within a carrier under pressurized fluid to thereby urge the brake pad and a brake disc to frictionally generate a braking force. However, in a conventional disc brake for a vehicle such as a truck, in which the total mass of the vehicle varies greatly between an empty state and a full state, there is a problem that the brake cannot sufficiently exert a braking action due to a large rear axle braking force when the vehicle is empty, and the brake cannot sufficiently exert a braking action due to a small rear axle braking force when the vehicle is full. It is therefore necessary to provide a brake suitable for vehicles with a large total mass variation in both empty and full load conditions.
Disclosure of Invention
The utility model provides a brake with variable braking force, which is used for overcoming at least one technical problem existing in the prior art.
The embodiment of the utility model provides a brake with variable braking force, which comprises the following components:
the brake caliper and the brake disc are fixedly connected to the hub of the vehicle, and the brake caliper spans across the two sides of the brake disc in a C shape; the brake caliper is characterized in that the brake caliper is positioned at two sides of a disc body of the brake disc, a first friction plate and a second friction plate are symmetrically arranged at two sides of the brake caliper, a first hydraulic cavity, a second hydraulic cavity, a first oil inlet and a second oil inlet are formed in one side of the brake caliper, where the first friction plate is arranged, the first oil inlet is communicated with the first hydraulic cavity, and the second oil inlet is communicated with the second hydraulic cavity;
the first hydraulic cavity is internally provided with a spring, one end of the spring is propped against the end part, away from the first oil inlet, of the first hydraulic cavity, a first piston with an I-shaped section is inserted into the cavity of the spring, one end, away from the first oil inlet, of the first piston with the I-shaped section is a first hollow cavity with a first cross section area, the other end, close to the first oil inlet, of the first piston is a second hollow cavity with a second cross section area, and the other end of the spring is propped against the end part, away from the first oil inlet, of the second hollow cavity; wherein the first cross-sectional area is numerically smaller than the second cross-sectional area;
and a second piston is arranged in the second hydraulic cavity, and the first piston and the second piston are used for outputting hydraulic power.
Preferably, a first elastic sealing ring is arranged at the matching position of the first piston and the brake caliper, and a second elastic sealing ring is arranged at the matching position of the second piston and the brake caliper.
Preferably, a first groove is further formed in the side, facing the first oil inlet, of the first piston, and the first groove is communicated with the first hydraulic cavity.
Preferably, a second groove is further formed in the second piston facing the second oil inlet, and the second groove is communicated with the first hydraulic cavity.
Preferably, the brake calipers are provided with heat dissipation ribs for increasing heat dissipation area.
Preferably, the cross-sectional area of the first hydraulic chamber is the same as the cross-sectional area of the second hydraulic chamber.
Preferably, the brake further comprises a guide pin and a brake caliper bracket, a through hole is formed in the brake caliper, a screw hole is formed in the brake caliper bracket, and the guide pin penetrates through the through hole and the screw hole.
The technical effects of the embodiment of the utility model can include: the utility model provides a brake with variable braking force, which is equivalent to a brake comprising two brake pumps with small cylinder diameters compared with the prior brake comprising one large brake pump, wherein a piston is arranged in a hydraulic cavity of one brake pump and used for increasing braking force required by the corresponding brake pump when working. Therefore, when the vehicle is in idle load, the braking force required by the rear brake of the vehicle is small, when the brake pump provided with the piston is acted by lower brake fluid, the thrust generated by the brake fluid on the piston is insufficient to overcome the elastic force generated by the spring, so the brake pump can not generate braking force, the brake is equivalent to the brake pump with only one small cylinder diameter, at the moment, the braking force requirement can be met under the independent action of the brake pump without the piston, and the problem that the wheel lock of the brake of the existing vehicle can be generated under the small oil pressure due to overlarge is solved. When the vehicle is fully loaded, the braking force required by the large axle load is large, so that the required braking force is high, the thrust generated by the braking force on the piston overcomes the elasticity generated by the spring along with the improvement of the braking force, so that the pressure on the friction plate is increased, the friction force between the friction plate and the braking disc is increased, further, the larger braking force is generated under the same oil pressure effect, the pressure of the oil pressure is reduced under the condition of a certain braking force, or the higher braking force is generated under the same oil pressure, and the problem of insufficient braking force of the brake under the condition of full loading is solved.
Drawings
In order to more clearly illustrate the embodiments of the utility model or the technical solutions in the prior art, the drawings that are required in the embodiments or the description of the prior art will be briefly described, it being obvious that the drawings in the following description are only some embodiments of the utility model, and that other drawings may be obtained according to these drawings without inventive effort for a person skilled in the art.
FIG. 1 is a schematic view of a prior art floating caliper disc brake;
fig. 2 is a cross-sectional view of a brake with variable braking force provided by the present utility model.
Wherein 1 denotes a caliper body, 2 denotes a guide post, 3 denotes a brake disc in an existing brake, 4 denotes a knuckle, 5 denotes a first friction plate in an existing brake, 6 denotes a second friction plate in an existing brake, 7 denotes an oil seal, 8 denotes a piston in an existing brake, 9 denotes a chamber of a brake pump, 10 denotes an oil inlet, 11 denotes a first brake pump, 12 denotes a second brake pump, 13 denotes a first friction plate in a brake provided by the present utility model, 14 denotes a brake disc, 15 denotes a first liquid inlet, 16 denotes a first piston, 17 denotes a spring, 18 denotes a second liquid inlet, and 19 denotes a second piston.
Detailed Description
As described in the foregoing background section, the disc brake mainly comprises a brake disc, a wheel cylinder, a brake caliper, an oil pipe and other components, and is an important component in a brake system device. In order to provide a specific description of the variable braking force brake according to the present utility model by way of comparison, the working principle of the conventional disc brake will be described with reference to fig. 1.
As shown in fig. 1, fig. 1 is a schematic structural diagram of a conventional floating caliper disc brake, as shown in fig. 1, high-pressure brake fluid enters a chamber 9 of a brake pump through an oil inlet 10, a brake pump piston 8 moves along the direction indicated by an arrow of Fp1 under the action of thrust Fp1 generated by the high-pressure brake fluid, and also under the reaction of force Fp1, the caliper body 1 moves on a guide post 2 along the direction indicated by an arrow of Fp2, the guide post 2 is rigidly mounted on a knuckle 4, a brake disc 3 and wheels synchronously rotate relative to the knuckle 4, the movement of the caliper body and the piston pushes a friction disc 6 and the caliper body 1 to move and compress the brake disc 3, the caliper body and the piston respectively enable the friction discs 5 and 6 to generate pressures of Fp1 and Fp2 on the brake disc, and under the action of the friction discs, the friction moment for preventing the rotation of the brake disc is generated, finally, the rotation of the brake disc 3 and the wheels is stopped, the friction moment generates braking force along the running direction of the wheels, and finally the vehicle is stopped.
The commercial vehicle has smaller axle load after no load, the braking force of the brake has a direct proportion relation with the axle load, the wheel can be close to stop rotating by the braking force generated under the condition of smaller oil pressure, and the wheel starts sliding and the braking force is not increased any more under the state of stopping rotating, so that the braking efficiency of the brake can not be fully exerted, and the characteristic of larger specification of the brake is shown; the utility model provides a double-pump brake with a spring adjusting function, which aims to solve the problem that the brake has a large axle load after full load and the same brake, wheels can not reach a state of nearly stopping rotation under high oil pressure, so that the braking distance is increased, a vehicle can not stop, and the performance of the brake is smaller.
The following description of the embodiments of the present utility model will be made clearly and completely with reference to the accompanying drawings, in which it is apparent that the embodiments described are only some embodiments of the present utility model, but not all embodiments. All other embodiments, which can be made by those skilled in the art based on the embodiments of the utility model without any inventive effort, are intended to be within the scope of the utility model.
It should be noted that the terms "comprising" and "having" and any variations thereof in the embodiments of the present utility model and the accompanying drawings are intended to cover non-exclusive inclusions. For example, a process, method, system, article, or apparatus that comprises a list of steps or elements is not limited to only those listed steps or elements but may include other steps or elements not listed or inherent to such process, method, article, or apparatus.
As shown in fig. 2, fig. 2 is a sectional view of a brake with variable braking force according to the present utility model, which is mainly a double pump brake with spring adjustment, and in order to more clearly explain the structure of the double pump brake in fig. 2, a structure common to the conventional disc brake illustrated in fig. 1 is briefly described, focusing on the improvement of the conventional brake.
The variable braking force brake provided in fig. 2 mainly comprises a brake caliper and a brake disc 14, wherein the brake disc 14 is fixedly connected to a hub of a vehicle, and the brake caliper spans across the brake disc 14 in a C shape. The brake disc 14 is arranged on two sides of a disc body, a first friction plate 13 and a second friction plate are symmetrically arranged on two sides of a brake caliper, a first hydraulic cavity, a second hydraulic cavity, a first oil inlet 15 and a second oil inlet 18 are formed in one side of the brake caliper, where the first oil inlet 15 is communicated with the first hydraulic cavity, and the second oil inlet 18 is communicated with the second hydraulic cavity. The first oil inlet 15 is used for enabling brake fluid to enter a cavity of a first hydraulic cavity so as to generate hydraulic pressure on a first piston 16 to be described below, and the second oil inlet 18 is used for enabling brake fluid to enter a cavity of a second hydraulic cavity so as to generate hydraulic pressure on a second piston 19 to be described below.
As shown in fig. 2, a spring 17 is arranged in the first hydraulic cavity, one end of the spring 17 abuts against the end part of the first hydraulic cavity, which is far away from the first oil inlet 15, a first piston 16 with an I-shaped section is inserted into the cavity of the spring 17, one end of the first piston 16, which is far away from the first oil inlet, is a first hollow cavity with a first cross-sectional area, the other end of the first piston 16, which is close to the first oil inlet 15, is a second hollow cavity with a second cross-sectional area, and the other end of the spring 17 abuts against the end part of the second hollow cavity, which is far away from the first oil inlet 15; wherein the first cross-sectional area is smaller in value than the second cross-sectional area. A second piston 19 is arranged in the second hydraulic chamber, and the first piston 16 and the second piston 19 are used for hydraulic power output.
In the following description of the function of the spring 17 described in the previous paragraph, it is mentioned that the spring 17 is arranged in the first hydraulic chamber, the first piston 16 is inserted in the cavity of the spring 17, and by the arrangement of the abutment position of the spring 17 described in the previous paragraph, when brake fluid enters the first hydraulic chamber and generates hydraulic pressure to the first piston 16, the spring 17 contracts and generates an elastic force in the opposite direction to the hydraulic pressure, so that the arrangement of the spring 17 makes the hydraulic pressure required for the first piston 16 to push the first friction plate 13 and thereby generate a braking force to the brake disc larger than the second piston 19. The arrangement of the device ensures that the brake pump provided by the utility model is equivalent to a brake pump with two smaller cylinder diameters (namely the first brake pump 11 and the second brake pump 12) compared with the brake pump of the existing brake, and theoretically, the cylinder diameters of the two smaller cylinder diameters can be half of the cylinder diameter of the existing brake, and the specific size can be specifically set according to the actual situation.
The present utility model provides a brake with variable braking force, which is equivalent to a brake comprising two brake pumps with small cylinder diameters compared with the existing brake comprising one large brake pump, wherein a piston is arranged in a hydraulic cavity of one brake pump (namely a first brake pump 11) for increasing braking force required by the corresponding brake pump when working. Therefore, when the vehicle is in idle load, the braking force required by the rear brake of the vehicle is small, when the brake pump provided with the piston is acted by lower brake fluid, the thrust generated by the brake fluid on the piston is insufficient to overcome the elastic force generated by the spring, so the brake pump can not generate braking force, the brake is equivalent to the brake pump with only one small cylinder diameter, at the moment, the braking force requirement can be met under the independent action of the brake pump without the piston, and the problem that the wheel lock of the brake of the existing vehicle can be generated under the small oil pressure due to overlarge is solved. When the vehicle is fully loaded, the braking force required by the large axle load is large, so that the required braking force is high, the thrust generated by the braking force on the piston overcomes the elasticity generated by the spring along with the improvement of the braking force, so that the pressure on the friction plate is increased, the friction force between the friction plate and the braking disc is increased, further, the larger braking force is generated under the same oil pressure effect, the pressure of the oil pressure is reduced under the condition of a certain braking force, or the higher braking force is generated under the same oil pressure, and the problem of insufficient braking force of the brake under the condition of full loading is solved.
It should be noted that, the aforementioned brake pump without a spring is the same as the brake pad in the prior art in structural design, and the difference between the brake with the variable braking force provided by the present utility model and the brake limited to the prior art is mainly described in the foregoing, and the parts of the variable brake which are the same as those of the prior art are not described in detail, for example, the specific structure that the brake caliper can span across the two sides of the brake disc 14 in a C-type floatable manner can refer to the prior art brake.
The working principle of the brake with variable braking force provided by the utility model is described below:
in the existing brake adopting a single brake pump, when a vehicle is in no load, the rear wheel can not be locked under a small oil pressure, and the wheel can not reach the required braking force under the action of a high brake oil pressure when the vehicle is in full load. If the dual pump brake scheme provided by the utility model and shown in fig. 2 is adopted, the single cylinder brake pump with a constant piston area is divided into two brake pumps, and the brake pump without a spring (namely the second brake pump 12) has the same structural design as the brake pad in the prior art.
By adopting the scheme, the brake pump in the existing brake is divided into two small brake pumps (namely, the first brake pump 11 and the second brake pump 12), 15 and 18 are liquid inlets of brake liquid, when the vehicle is empty, the brake force required by the rear brake of the vehicle is small, at the moment, the requirement of the brake force can be met under the independent action of the second brake pump 12 without the spring 17, and when the first brake pump 11 with the spring 17 is under the action of the brake liquid under lower pressure, the thrust generated by the brake liquid on the piston is insufficient to overcome the elastic force generated by the spring 17, so that the first brake pump 11 can not generate the brake force, and the brake pump with the small cylinder diameter acts on the whole, thereby solving the problem that the wheel locking is generated by overlarge brake under the condition of small oil pressure.
When the vehicle is fully loaded, the required braking force is large due to the large axle load, the required braking force is high, with the increase of the braking force (controlled by the degree of stepping on the pedal), the thrust generated by the braking force on the first piston 16 provided with the spring 17 overcomes the elastic force generated by the spring 17, the first piston 16 can push the first friction plate 13, namely, besides the second piston 19 to act, the first piston 16 also starts to act, the pressure acting on the first friction plate 13 is increased as compared with that of a single braking pump, the friction force of the first friction plate 13 and the braking disc 14 is increased, and further, the larger braking force is generated under the same oil pressure, the oil pressure is reduced under the condition of a certain braking force, or the higher braking force is generated under the same oil pressure, and the problem of insufficient braking force of the brake under the fully loaded condition is solved.
Next, a description will be given of a modification of a brake of a variable braking force provided in the embodiment of the specification.
In order to prevent the high-pressure brake fluid from flowing out and further affecting the normal operation of the brake, in an alternative scheme, a first elastic sealing ring can be arranged at the matching position of the first piston and the brake caliper, and a second elastic sealing ring can be arranged at the matching position of the second piston and the brake caliper. Meanwhile, a first groove is formed in the side, facing the first oil inlet, of the first piston, and the first groove is communicated with the first hydraulic cavity.
In a further optimized scheme, a second groove is further formed in the side, facing the second oil inlet, of the second piston, and the second groove is communicated with the first hydraulic cavity.
Further optimizing scheme can offer the heat dissipation muscle that is used for increasing heat radiating area on the brake calliper. Because the brake is braked by the friction force between the brake block and the brake disc, a large amount of heat is generated in the braking process of the brake, and the heat dissipation area of the brake caliper can be increased by arranging the heat dissipation ribs on the brake caliper, so that the heat generated in the braking process can be timely and effectively taken away, and the brake is ensured to work in a proper temperature all the time.
In a further preferred embodiment, the cross-sectional area of the first hydraulic chamber is the same as the cross-sectional area of the second hydraulic chamber.
Further optimizing scheme, the brake still includes guide pin and brake caliper support, has seted up the through-hole on the brake caliper, has seted up the screw on the brake caliper support, and the guide pin passes through-hole and screw.
Further optimizing scheme, the depth of first hydraulic pressure chamber is the same with the second hydraulic pressure chamber, and the length of first piston is less than the length of second piston.
Those of ordinary skill in the art will appreciate that: the drawing is a schematic diagram of one embodiment and the modules or flows in the drawing are not necessarily required to practice the utility model.
Those of ordinary skill in the art will appreciate that: the modules in the apparatus of the embodiments may be distributed in the apparatus of the embodiments according to the description of the embodiments, or may be located in one or more apparatuses different from the present embodiments with corresponding changes. The modules of the above embodiments may be combined into one module, or may be further split into a plurality of sub-modules.
Finally, it should be noted that: the above embodiments are only for illustrating the technical solution of the present utility model, and are not limiting; although the utility model has been described in detail with reference to the foregoing embodiments, it will be understood by those of ordinary skill in the art that: the technical scheme described in the foregoing embodiments can be modified or some of the technical features thereof can be replaced by equivalents; such modifications and substitutions do not depart from the spirit and scope of the technical solutions of the embodiments of the present utility model.

Claims (7)

1. A variable braking force brake, comprising:
the brake caliper and the brake disc are fixedly connected to the hub of the vehicle, and the brake caliper spans across the two sides of the brake disc in a C shape; the brake caliper is characterized in that the brake caliper is positioned at two sides of a disc body of the brake disc, a first friction plate and a second friction plate are symmetrically arranged at two sides of the brake caliper, a first hydraulic cavity, a second hydraulic cavity, a first oil inlet and a second oil inlet are formed in one side of the brake caliper, where the first friction plate is arranged, the first oil inlet is communicated with the first hydraulic cavity, and the second oil inlet is communicated with the second hydraulic cavity;
the first hydraulic cavity is internally provided with a spring, one end of the spring is propped against the end part, away from the first oil inlet, of the first hydraulic cavity, a first piston with an I-shaped section is inserted into the cavity of the spring, one end, away from the first oil inlet, of the first piston with the I-shaped section is a first hollow cavity with a first cross section area, the other end, close to the first oil inlet, of the first piston is a second hollow cavity with a second cross section area, and the other end of the spring is propped against the end part, away from the first oil inlet, of the second hollow cavity; wherein the first cross-sectional area is numerically smaller than the second cross-sectional area;
and a second piston is arranged in the second hydraulic cavity, and the first piston and the second piston are used for outputting hydraulic power.
2. The brake of claim 1, wherein a first elastic sealing ring is provided at a location where the first piston engages the brake caliper, and a second elastic sealing ring is provided at a location where the second piston engages the brake caliper.
3. The brake of claim 1, wherein the first piston is further provided with a first groove facing the first oil inlet side, the first groove communicating with the first hydraulic chamber.
4. The brake of claim 1, wherein the second piston is further provided with a second groove facing the second oil inlet side, the second groove communicating with the first hydraulic chamber.
5. The brake with variable braking force according to claim 1, wherein the brake caliper is provided with heat radiation ribs for increasing a heat radiation area.
6. The variable braking force brake of claim 1, wherein the first hydraulic chamber is the same cross-sectional area as the second hydraulic chamber.
7. The brake of claim 1, further comprising a guide pin and a brake caliper bracket, wherein the brake caliper bracket has a through hole formed therein, and wherein the brake caliper bracket has a screw hole formed therein, the guide pin passing through the through hole and the screw hole.
CN202322100691.XU 2023-08-07 2023-08-07 Brake with variable braking force Active CN220302596U (en)

Priority Applications (1)

Application Number Priority Date Filing Date Title
CN202322100691.XU CN220302596U (en) 2023-08-07 2023-08-07 Brake with variable braking force

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
CN202322100691.XU CN220302596U (en) 2023-08-07 2023-08-07 Brake with variable braking force

Publications (1)

Publication Number Publication Date
CN220302596U true CN220302596U (en) 2024-01-05

Family

ID=89349583

Family Applications (1)

Application Number Title Priority Date Filing Date
CN202322100691.XU Active CN220302596U (en) 2023-08-07 2023-08-07 Brake with variable braking force

Country Status (1)

Country Link
CN (1) CN220302596U (en)

Similar Documents

Publication Publication Date Title
US7377368B2 (en) Disc brake with brake linings guided on bolts
FI108073B (en) Wet Disc Brake
CN100470078C (en) Parking brake device
US2419113A (en) Booster brake
US6491138B1 (en) Disc brake
CN101876357A (en) Self-energizing effort disk brake
CN220302596U (en) Brake with variable braking force
US10781871B2 (en) Disc brake caliper body
CN216715050U (en) Double-brake caliper automobile brake assembly
US3548973A (en) Stirrup for disc brake
US2968370A (en) Disk brakes
CN113124072B (en) Multi-brake shoe drum brake and working method
CN214118817U (en) Clutch brake cylinder assembly
CN116373827A (en) Braking method for realizing zero drag of braking system
CN116461706A (en) Damping device and fixed wing unmanned aerial vehicle recovery system using same
CN107191514A (en) A kind of static hydraulic brake system
CN106641026A (en) Drum type brake with automatic and continuous adjustable gap
JPS63103782A (en) Disk-brake mechanism
RU2115576C1 (en) Vehicle brake system
CN105465250A (en) Automobile disc brake lining pad having strong heat dissipation performance
CN109654132A (en) A kind of heat sinking brake drum for automobile
CN219472607U (en) Fixed caliper braking system assembly with electronic parking function
CN211252547U (en) Electrohydraulic wire-controlled brake device
CN213776155U (en) Mechanical brake
CN215567546U (en) Cylinder diameter variable brake caliper and vehicle with same

Legal Events

Date Code Title Description
GR01 Patent grant
GR01 Patent grant