CN214424956U

CN214424956U - Motor drive drum-type parking brake

Info

Publication number: CN214424956U
Application number: CN202022669173.6U
Authority: CN
Inventors: 田草原
Original assignee: Bazhou Huacheng Automobile Brake Co ltd
Current assignee: Bazhou Huacheng Automobile Brake Co ltd
Priority date: 2020-11-18
Filing date: 2020-11-18
Publication date: 2021-10-19
Anticipated expiration: 2030-11-18

Abstract

The utility model discloses a motor-driven drum-type parking brake, including installing preceding brake shoe, adjustment ratchet and the back brake shoe on the braking bottom plate, be connected with the return spring on preceding brake shoe and the back brake shoe, the upper end of preceding brake shoe and back brake shoe articulates on the shoe supporting pin, the lower extreme of preceding brake shoe and back brake shoe with the clearance adjustment use adjust ratchet and return spring down be connected; the brake further comprises a transmission mechanism assembly, and the transmission mechanism assembly is connected with the front brake shoe and the rear brake shoe through a piston for supporting. Generally speaking, the utility model discloses think about ingenious, compact structure is reasonable, and worm gear collects screw rod screw sleeve in an organic whole, thereby it removes and realizes the brake braking operation to drive the brake shoe before the piston drives through the motor drive worm gear transmission, and whole mechanical transmission's transmission time is rapider and efficiency is higher.

Description

Motor drive drum-type parking brake

Technical Field

The utility model relates to a parking brake technical field especially relates to a motor drive drum-type parking brake.

Background

At present, the brake applied to the electronic parking brake function of the automobile mainly adopts a caliper type EPB and a pull rope type EPB, the caliper type EPB is relatively high in cost and expensive in later maintenance, and the parking efficiency caused by a disc structure is not high. The guyed EPB is too heavy, the parts are complicated, the functional response time is too long, the cost is basically equal to that of the caliper EPB, and the guyed EPB is gradually eliminated in the market after being too lagged behind relative technology.

In order to solve the problem that above electron parking brake type exists, the utility model provides a motor drive drum-type parking brake is used for solving above-mentioned not enough, satisfies automobile host factory and user's tangible demand.

SUMMERY OF THE UTILITY MODEL

The utility model aims at providing a motor drive drum-type parking brake, it is slower to solve the prior art stopper reaction, problem that the structure is complicated.

In order to solve the technical problem, the utility model adopts the following technical scheme:

the utility model relates to a motor drive drum-type parking brake, including installing preceding brake shoe, adjustment ratchet and the back brake shoe on the braking bottom plate, be connected with return spring on preceding brake shoe and the back brake shoe, the upper end of preceding brake shoe and back brake shoe articulates on the shoe supporting pin, the lower extreme of preceding brake shoe and back brake shoe with the clearance adjustment use adjust ratchet and return spring down be connected; the brake further comprises a transmission mechanism assembly, and the transmission mechanism assembly is connected with the front brake shoe and the rear brake shoe through a piston for supporting.

Furthermore, the transmission mechanism assembly comprises a motor reducing mechanism, a worm wheel and a screw rod, the output shaft end of the motor reducing mechanism is in transmission connection with one end of the worm, the worm is in inclined arrangement and meshing connection with the worm wheel, the screw rod is in threaded connection with the inner portion of the worm wheel, one end of the piston is fixedly connected with the rear brake shoe, and the salient point of the other end of the piston is in contact with the worm wheel.

Further, motor reduction gears's output shaft end with the tail end of worm alternates the cooperation and is connected, the number of heads of worm sets up to 2, the number of teeth of worm wheel sets up to 22, the worm wheel with the transmission screw thread outer wall of worm is 20 pressure angle and meshes mutually, the pitch of screw rod sets up to 2mm, and the tooth form angle of screw rod sets up 30, the fluting one end of piston with the horseshoe contact and the interlock of back brake shoe are motionless, the steel ball convex surface one end of piston with the concave surface one end contact of worm wheel just has relative roll trend.

Still further, the motor reduction mechanism specifically adopts two-stage planetary gear reduction, the transmission ratio of each stage is 4.5, the transmission ratio of the worm wheel and the worm is 11, the transmission ratio of the worm wheel and the screw is 11, and the total transmission ratio is 222.75.

Still further, the number of teeth of the worm wheel is designed to be 22, the modulus is set to be 0.65, the pressure angle is set to be 20 degrees, the thread pitch is designed to be 2, the number of heads of the worm is designed to be 2, the modulus is designed to be 0.65, and the thread pitch is set to be 2.041.

Furthermore, one end of the piston is provided with a U-shaped groove, and the U-shaped groove is in occlusion connection with a shoe of the rear brake shoe; one end of the piston is connected with a steel ball, and the steel ball protrudes out of the end face of the piston and is abutted against the concave face of the worm wheel.

And further, a motor speed reducing mechanism of the transmission mechanism assembly is electrically connected with a PLC (programmable logic controller) of the vehicle, and is transmitted to the motor speed reducing mechanism to start or stop working according to an electric control input signal sent by the PLC and a signal fed back by the stress condition of the mechanical transmission part.

Compared with the prior art, the utility model discloses a beneficial technological effect:

the utility model relates to a motor-driven drum-type parking brake, which comprises a front brake shoe, an adjusting ratchet wheel and a rear brake shoe which are arranged on a brake bottom plate, wherein the front brake shoe and the rear brake shoe are connected with an upper return spring; the brake shoe brake device is characterized by further comprising a transmission mechanism assembly, wherein the transmission mechanism assembly comprises a motor speed reducing mechanism, a worm wheel and a screw rod, the output shaft end of the motor speed reducing mechanism is in transmission connection with one end of the worm, the worm is obliquely arranged and meshed with the worm wheel, the screw rod is in threaded connection with the inner part of the worm wheel, one end of the piston is immovable in contact with the top end of the rear brake shoe, and a convex point at the other end of the piston is in contact with the worm wheel; when the worm-gear transmission device works, the motor rotates in a positive rotation mode, kinetic energy is transmitted to the worm to rotate after the motor is subjected to speed reduction transmission through the secondary planetary gear, the worm drives the worm gear to perform transmission, the worm gear slides relative to a meshing part of the worm gear and gradually enters and gradually exits meshing to realize third-stage transmission, a convex point at the other end of the piston is in contact with the worm gear and has a relative rolling trend, the worm gear is used as a screw sleeve to be matched with the screw rod, and the screw sleeve is used as fourth-stage sub transmission; because the worm wheel (threaded sleeve) rotates, the piston is contacted with one end of the worm wheel to be relatively immobile, and the other end of the worm wheel causes the screw rod to rotate and roll to generate a stroke to be ejected out in the direction of the front brake shoe, so that the upper end of the front brake shoe is separated from the shoe supporting pin, after the brake shoe is contacted with a rotating brake disc, the brake drum drives the two brake shoes to rotate in the rotating direction under the action of friction torque until the rear brake shoe is abutted against the supporting pin, and then the brake shoes are further pressed against the brake disc. The rear shoe is in a force-increasing state at the moment, because the pressing force of the rear brake shoe comprises the thrust of the opening force of the screw rod to the rear brake shoe, and the thrust applied to the lower end of the rear brake shoe by the floating adjusting ratchet wheel is 2-3 times larger than the opening force under the action of the force-increasing action of the front brake shoe, the two brake shoes generate brake torque higher than the brake torque normally used to realize the parking function; after parking braking is finished, the motor reducing mechanism assembly receives a reverse rotation electric signal to drive the worm to rotate reversely, so that the worm wheel (threaded sleeve) rotates reversely, and meanwhile, the pulling force of the upper return spring returning to the initial position is received, the gap between the brake shoe and the brake disc is eliminated, and the parking braking of the automobile is relieved. Compare in caliper formula EPB and stay cable formula EPB, the utility model discloses unique turbine worm collects screw rod swivel nut in the speed reduction drive mechanism design of an organic whole, and the saving and manufacturing cost of making spare part relatively are lower, and response time shortens 0.3s, makes product precision and noise performance perfect more, and the high and stable product work efficiency that makes of performance improves greatly.

Generally speaking, the utility model discloses think about ingenious, compact structure is reasonable, and worm gear collects screw rod screw sleeve in an organic whole, thereby it removes and realizes the brake braking operation to drive the brake shoe before the piston drives through the motor drive worm gear transmission, and whole mechanical transmission's transmission time is rapider and efficiency is higher.

Drawings

The present invention will be further explained with reference to the following description of the drawings.

FIG. 1 is a front view of a motor-driven drum type parking brake of the present invention;

FIG. 2 is a right side view of the motor-driven drum type parking brake of the present invention;

FIG. 3 is a schematic view of the connection structure of the transmission assembly of the present invention;

FIG. 4 is a schematic view of the transmission mechanism of the present invention;

description of reference numerals: 1. a front brake shoe; 2. adjusting the ratchet wheel; 3. a rear brake shoe; 4. an upper return spring; 5. a transmission mechanism assembly; 501. a worm; 502. a piston; 503. a turbine; 504. a screw; 6. a motor reduction mechanism; 7. braking the bottom plate; 8. a brake disc; 9. and a lower return spring.

Detailed Description

As shown in fig. 1 to 4, a motor-driven drum type parking brake includes a front brake shoe 1, an adjusting ratchet 2 and a rear brake shoe 3 mounted on a brake base plate 7, wherein the front brake shoe 1 and the rear brake shoe 3 are connected with an upper return spring 4, the upper ends of the front brake shoe 1 and the rear brake shoe 3 are hinged on a shoe support pin, and the lower ends of the front brake shoe 1 and the rear brake shoe 3 are connected with the adjusting ratchet 2 and a lower return spring 9 for gap adjustment; the brake further comprises a transmission mechanism assembly 5, wherein the transmission mechanism assembly 5 is connected with the front brake shoe 1 and the rear brake shoe 3 through a supporting piston 502.

As shown in fig. 3 and 4, the transmission mechanism assembly 5 includes a motor speed reducing mechanism, a worm 501, a worm wheel 503 and a screw rod 504, an output shaft end of the motor speed reducing mechanism is in transmission connection with one end of the worm 501, the worm 501 and the worm wheel 503 are in inclined arrangement and meshing connection, the screw rod 504 is connected to the worm wheel 503 through an internal thread, one end of the piston 502 is fixedly connected with the rear brake shoe 3, and a protruding point at the other end of the piston 502 is in contact with the worm wheel 503. And the motor speed reducing mechanism of the transmission mechanism assembly 5 is electrically connected with a PLC (programmable logic controller) of the vehicle, and is transmitted to the motor speed reducing mechanism to start or stop working according to an electric control input signal sent by the PLC and a signal fed back by the stress condition of the mechanical transmission part. The transmission mechanism assembly 5 determines the working time according to the input signal of the electronic control unit, and on the contrary, the electronic control unit determines the output signal of the next time according to the feedback signal of the stress condition of the mechanical transmission part of the transmission mechanism assembly 5. According to the abrasion condition of the front brake shoe 1 and the rear brake shoe 3, the electric control unit and the transmission mechanism assembly 5 work in cooperation to generate signals, so that the optimal ejection distance of the transmission mechanism assembly 5 is determined, the self-adjusting function is achieved, and reasonable gaps are kept among the front brake shoe 1, the rear brake shoe 3 and the brake disc 8.

Specifically, the output shaft end of the motor reduction mechanism is in inserting fit connection with the tail end of the worm 501, the number of the heads of the worm 501 is set to be 2, the number of teeth of the worm wheel 503 is set to be 22, the worm wheel 503 is meshed with the outer wall of the transmission thread of the worm 501 by a pressure angle of 20 degrees, the thread pitch of the screw rod 504 is set to be 2mm, the thread form angle of the screw rod 504 is set to be 30 degrees, the slotting end of the piston 502 is in contact with and is meshed with the horseshoe of the rear brake shoe 3, and the convex end of the steel ball of the piston 502 is in contact with the concave end of the worm wheel 503 and has a relative rolling trend.

The motor speed reducing mechanism specifically adopts a two-stage planetary gear for speed reduction, the transmission ratio of each stage is 4.5, the transmission ratio of the worm wheel 503 to the worm 501 is 11, the transmission ratio of the worm wheel 503 to the screw 504 is 11, and the total transmission ratio is 222.75.

Specifically, in one embodiment, the number of teeth of the worm wheel 3 is designed to be Z₂22, the modulus is set to 0.65, the lead angle is set to 20 °, the pitch is set to 2, the pitch diameter is 14.3mm, the base circle is 13.43mm, the deflection coefficient is 0.6, the crest height coefficient is 1, the tip clearance coefficient is 0.25, and the tooth form angle is 30 °. The number of the heads of the worm 1 is designed to be Z ₁2, the modulus is designed to be 0.65,the pitch was set at 2.041 and the lead was 4.082.

Furthermore, appropriate adjustments of relevant parameters can be made according to the actual required transmission ratio.

One end of the piston 502 is provided with a U-shaped groove, and the U-shaped groove is meshed and connected with a shoe of the rear brake shoe 3; one end of the piston 502 is connected with a steel ball which protrudes out of the end surface of the piston 502 and is abutted against the concave surface of the worm wheel 503.

The working process of the utility model is as follows:

firstly, the positive electrode and the negative electrode of a motor are electrified, a current instruction is input by a vehicle-mounted electronic control unit, the motor rotates in a positive rotation mode, kinetic energy is transmitted to a worm 501 to rotate after the motor is subjected to speed reduction transmission through a secondary planetary gear, the worm 501 drives a worm wheel 503 to slide relative to a meshing position of the worm wheel 503, and gradually enters and gradually exits meshing to realize third-stage transmission, a piston 502 is an independent part, one end of the piston is in contact with a rear brake shoe 3 and does not rotate, a convex point at the other end of the piston is in contact with the worm wheel 503 and has a relative rolling trend, and the worm wheel 503 is used as a threaded sleeve at the moment and is matched with a screw 504 to be used as a screw sleeve to be used for fourth-stage sub transmission; because the worm wheel 503 (threaded sleeve) rotates, the piston 502 contacts with one end of the piston relatively immovably, and one end of the piston causes the screw rod 504 to rotate and roll to generate a stroke to eject out towards the direction of the front brake shoe 1, so that the upper ends of the front brake shoe and the rear brake shoe are both away from the shoe supporting pin, and after the brake shoes are contacted with a rotating brake disc, the brake disc drives the two brake shoes to rotate along the rotating direction under the action of friction torque until the rear brake shoe abuts against the brake disc, then the brake shoes and the brake disc are further pressed, at the moment, the rear brake shoe is in a force increasing state, and under the action of the force increasing of the front brake shoe, the thrust force applied to the lower end of the rear brake shoe by the floating adjusting ratchet 2 is 2-3 times larger than the opening force, and the two brake shoes generate a brake torque higher than the brake torque normally used to realize the parking function. The worm gear and the worm are integrated with the screw sleeve, and the whole mechanical transmission is quicker in corresponding time and higher in efficiency.

When the parking brake is finished, the motor rotates reversely, and the motor is subjected to a series of reverse transmissions and the tension of the upper return spring, so that the gap between the brake shoe and the brake disc 8 is eliminated, and the parking brake of the automobile is released.

The above-mentioned embodiments are only intended to describe the preferred embodiments of the present invention, but not to limit the scope of the present invention, and those skilled in the art should also be able to make various modifications and improvements to the technical solution of the present invention without departing from the spirit of the present invention, and all such modifications and improvements are intended to fall within the scope of the present invention as defined in the appended claims.

Claims

1. A motor-driven drum type parking brake comprises a front brake shoe (1), an adjusting ratchet wheel (2) and a rear brake shoe (3) which are arranged on a brake bottom plate (7), wherein the front brake shoe (1) and the rear brake shoe (3) are connected with upper return springs (4), the upper ends of the front brake shoe (1) and the rear brake shoe (3) are hinged on shoe supporting pins, and the lower ends of the front brake shoe (1) and the rear brake shoe (3) are connected with the adjusting ratchet wheel (2) and a lower return spring (9) for adjusting a gap; the method is characterized in that: the brake further comprises a transmission mechanism assembly (5), wherein the transmission mechanism assembly (5) is connected with the front brake shoe (1) and the rear brake shoe (3) through a supporting piston (502).

2. The motor-driven drum parking brake of claim 1, characterized in that: the transmission mechanism assembly (5) comprises a motor speed reducing mechanism, a worm (501), a worm wheel (503) and a screw rod (504), an output shaft end of the motor speed reducing mechanism is in transmission connection with one end of the worm (501), the worm (501) is in inclined arrangement, meshing connection with the worm wheel (503), the screw rod (504) is in threaded connection with the inner portion of the worm wheel (503), one end of the piston (502) is fixedly connected with the rear brake shoe (3), and a protruding point at the other end of the piston (502) is in contact with the worm wheel (503).

3. The motor-driven drum parking brake of claim 2, characterized in that: motor reduction gears's output shaft end with the tail end of worm (501) alternates the cooperation and connects, the head number of worm (501) sets up to 2, the number of teeth of worm wheel (503) sets up to 22, worm wheel (503) with the transmission screw outer wall of worm (501) is 20 pressure angle and meshes mutually, the pitch of screw rod (504) sets up to 2mm, and the tooth form angle of screw rod (504) sets up 30, the fluting one end of piston (502) with the horseshoe contact and the interlock of back brake shoe (3) are motionless, the convex steel ball one end of piston (502) with the concave surface one end contact of worm wheel (503) just has the relative roll trend.

4. The motor-driven drum parking brake of claim 2, characterized in that: the motor speed reducing mechanism is specifically reduced by adopting a two-stage planetary gear, the transmission ratio of each stage is 4.5, the transmission ratio of the worm wheel (503) and the worm (501) is 11, the transmission ratio of the worm wheel (503) and the screw (504) is 11, and the total transmission ratio is 222.75.

5. The motor-driven drum parking brake of claim 2, characterized in that: the number of teeth of the worm wheel (503) is designed to be 22, the modulus is set to be 0.65, the pressure angle is set to be 20 degrees, the thread pitch is designed to be 2, the number of heads of the worm (501) is designed to be 2, the modulus is designed to be 0.65, and the thread pitch is set to be 2.041.

6. The motor-driven drum parking brake of claim 2, characterized in that: one end of the piston (502) is provided with a U-shaped groove, and the U-shaped groove is meshed and connected with a shoe of the rear brake shoe (3); one end of the piston (502) is connected with a steel ball, and the steel ball protrudes out of the end face of the piston (502) and is abutted against the concave face of the worm wheel (503).

7. The motor-driven drum parking brake of claim 1, characterized in that: and a motor speed reducing mechanism of the transmission mechanism assembly (5) is electrically connected with a PLC (programmable logic controller) of the vehicle, and is transmitted to the motor speed reducing mechanism to start or stop working according to an electric control input signal sent by the PLC and a signal fed back by the stress condition of a mechanical transmission part.