Automobile electronic brake booster device

Abstract

The present invention relates to an automobile electronic brake booster, which belongs to the field of automobile braking. It includes a shell cover, a guide rod, a housing, a return spring, a retaining ring, a main cylinder body, a main cylinder push rod, a feedback plate, a bracket, an active gear assembly, and a reduction gear assembly. The reduction gear assembly is connected to the nut assembly through helical gear meshing, the nut assembly is assembled in a rolling bearing, the bearing sleeve is riveted to the rolling bearing by interference, the nut assembly is threadedly connected to the screw assembly, the support plate of the screw assembly is interference-connected to the bracket assembly as a whole, and the push rod assembly is clearance-matched with the bracket assembly and the screw assembly respectively. The advantages are novel structure, fast response speed, no influence of air pressure, strong robustness, etc., which brings active safety to the automobile and is the development trend of the future driving brake system.

Description

Technical Field

[0001] The invention belongs to the field of automobile braking, in particular to the improvement of an electronic brake booster. Background Art

[0002] In previous automotive brake booster products, the automobile engine or vacuum pump was used to form a vacuum to provide a power source for the booster. The booster is designed with two chambers, front and rear, and both chambers are in a certain vacuum when the vehicle is driving. When the driver steps on the brake pedal, the rear chamber of the booster enters the atmosphere, forming a pressure difference with the front chamber. Due to the effect of atmospheric pressure, thrust is formed to assist the driver's pedaling force. At present, there are also motors used as power sources to assist the driver's braking, and related supporting structures need to be developed for this purpose to meet vehicle installation requirements. Summary of the invention

[0003] The present invention provides an automobile electronic brake booster device, which uses a motor as a power source, and finally converts rotational motion into linear motion through a gear system and a nut-screw assembly to assist the driver in braking.

[0004] The technical solution adopted by the present invention is: the shell cover and the guide rod are riveted to the shell body respectively, one end of the return spring is pressed on the retaining ring and the other end is pressed inside the shell cover, the main cylinder body is connected to the guide rod through a nut, the main cylinder push rod and the feedback plate are placed above the bracket in sequence, the driving gear assembly and the reduction gear assembly are meshed through helical gears, the bracket assembly and the guide rod are clearance-matched, the bracket assembly and the displacement sensor are hot-melt-connected, the reduction gear assembly and the nut assembly are meshed through helical gears, the nut assembly is assembled in the rolling bearing, the bearing sleeve and the rolling bearing are interference-riveted, the dust cover is interference-covered on the bearing sleeve, the nut assembly is threadedly connected to the screw assembly, the support plate of the screw assembly and the bracket assembly are interference-connected as a whole, the push rod assembly is clearance-matched with the bracket assembly and the screw assembly respectively, the washer is welded to the bottom of the screw of the screw assembly, and the push rod spring is located between the push rod spring seat and the washer.

[0005] The structure of the nut assembly is that the central gear and the secondary nut are respectively matched through the clearance of their own N guide grooves 1 and 2, the primary nut and the secondary nut are meshed through non-self-locking threads, and the head boss of the primary nut is matched and connected with the groove of the head of the secondary nut to ensure that they cannot fall out of each other.

[0006] The primary nut and the secondary nut are made of materials with a relatively small friction coefficient, such as polypropylene, polyoxymethylene, polyetheretherketone, etc., so that they cooperate with each other to generate the smallest possible friction force.

[0007] The structure of the screw assembly is that the support plate and the screw are connected by laser welding, and the washer ensures that the screw assembly will not fall out of the primary nut after the screw assembly travels a full stroke.

[0008] The structure of the bracket assembly is that the slider and the bracket are injection molded as one piece, the inside of the slider is a waist-shaped hole composed of two semicircles and a rectangle, and a rectangle with a length of a is extended in the middle of the two semicircles with a radius of R. The radius of the guide rod is R, which not only ensures that the slider can suppress the overall movement of the components, but also allows the whole to swing to both sides with a gap of a after the components are assembled.

[0009] The sliding block is made of wear-resistant plastic material, such as polyoxymethylene, polyetheretherketone, etc., and is molded by double-color injection molding or insert injection molding.

[0010] The structure of the push rod assembly is that the push rod and the connecting rod are riveted together, the magnet seat and the connecting rod are riveted together, the pressure block and the connecting rod are riveted together, and the permanent magnet and the magnet seat are connected together by injection molding.

[0011] The advantage of the present invention is its novel structure. It uses a motor-assisted braking mechanism to replace the vacuum-assisted braking mechanism of a traditional automobile, eliminates the vacuum source, uses a motor as a power source, transmits torque through the motor and the bevel gear, and then converts the rotational motion into linear motion through the nut and screw assembly, thereby forming a power assist. When the motor, system circuit, or vehicle power supply fails, the driver can provide braking force for the entire vehicle through the rigid connection of the booster to slow down or stop the vehicle. Compared with traditional vacuum booster devices, it has the characteristics of fast response speed, no influence of air pressure, simple mechanical structure, and strong robustness. After adding the control system, the booster device can be actively started to provide thrust for the brake master cylinder to form braking force, bringing active safety to the car, which is the development trend of future driving brake systems. It can be applied to conventional braking, wire control braking, and to vehicle active safety systems such as active collision avoidance (AEB), adaptive cruise control (ACC), intelligent driving, and brake energy recovery. BRIEF DESCRIPTION OF THE DRAWINGS

[0012] Figure 1 is a top view of the present invention;

[0013] Figure 2 yes Figure 1 AA section view;

[0014] Figure 3 yes Figure 1 BB cross-sectional view;

[0015] Figure 4 is a schematic structural diagram of a nut assembly of the present invention;

[0016] Figure 5 yes Figure 4 CC section view;

[0017] Figure 6 is a three-dimensional diagram of a nut assembly of the present invention;

[0018] Figure 7It is a schematic diagram of the structure of the central gear in the nut assembly of the present invention;

[0019] Figure 8 yes Figure 7 DD cross-sectional view;

[0020] Fig. 9 yes Figure 7 Rear view of

[0021] Fig.10 is a three-dimensional diagram of a central gear in a nut assembly of the present invention;

[0022] Fig.11 It is a structural schematic diagram of a primary nut in a nut assembly of the present invention;

[0023] Fig.12 yes Fig.11 EE cross-sectional view;

[0024] Fig.13 is a three-dimensional diagram of a primary nut in a nut assembly of the present invention;

[0025] Fig.14 It is a schematic structural diagram of a secondary nut in a nut assembly of the present invention;

[0026] Fig.15 yes Fig.14 FF cross-sectional view;

[0027] Fig.16 yes Fig.14 Rear view of

[0028] Fig.17 is a stereoscopic diagram of a secondary nut in a nut assembly of the present invention;

[0029] Fig.18 This is a working state diagram of the nut assembly in a normal state of the present invention;

[0030] Fig.19 is a working state diagram of the nut assembly in a failure state of the present invention;

[0031] Fig. 20 is a schematic structural diagram of the bracket assembly of the present invention;

[0032] Fig.21 It is a structural schematic diagram of a slider in a bracket assembly of the present invention;

[0033] Fig. 22 It is a schematic diagram showing the coordination of the bracket assembly, displacement sensor, screw assembly and nut assembly of the present invention. DETAILED DESCRIPTION

[0034] like Figure 1 , 23, the shell cover 1 and the guide rod 3 are riveted to the shell 7 respectively, one end of the return spring 2 is pressed on the retaining ring 11, and the other end is pressed inside the shell cover 1, the main cylinder body 20 is connected to the guide rod 3 through the nut 21, the main cylinder push rod 10 and the feedback plate 12 are placed on the bracket 4 in sequence, the driving gear assembly 18 and the reduction gear assembly 19 are meshed through the helical gears, the bracket assembly 4 and the guide rod 3 are clearance-matched, the bracket assembly 4 and the displacement sensor 22 are hot-melt-connected, and the reduction gear assembly 19 and the nut assembly 14 are connected through The helical gears are meshed and connected, the nut assembly 14 is assembled in the rolling bearing 6, the bearing sleeve 8 is interference riveted with the rolling bearing 6, the dust cover 9 is interference sleeved on the bearing sleeve 8, the nut assembly 14 is threadedly connected with the screw assembly 5, the support plate 5.1 of the screw assembly 5 is interference connected with the bracket assembly 4 as a whole, the push rod assembly 13 is clearance-matched with the bracket assembly 4 and the screw assembly 5 respectively, the washer 15 is welded to the bottom of the screw 5.2 of the screw assembly 5, and the push rod spring 16 is located between the push rod spring seat 17 and the washer 15.

[0035] like Figures 4 to 17 As shown, the structure of the nut assembly 14 is that the central gear 14.1 and the secondary nut 14.3 are respectively matched through the clearance of the N guide grooves 1 14.1.1 and the guide grooves 2 14.3.1, the primary nut 14.2 and the secondary nut 14.3 are meshed through non-self-locking threads, and the head boss 14.2.1 of the primary nut 14.2 is matched with the groove 14.3.2 of the head of the secondary nut 14.3 to ensure that they cannot come out of each other;

[0036] The primary nut 14.2 and the secondary nut 14.3 are made of materials with a small friction coefficient, such as polypropylene, polyoxymethylene, polyetheretherketone, etc., so that they cooperate with each other to generate as small a friction force as possible.

[0037] like Fig. 22 As shown, the structure of the screw assembly 5 is: the support plate 5.1 and the screw 5.2 are connected by laser welding, and the washer 15 ensures that the screw assembly 5 will not fall out of the primary nut 14.2 after the full stroke.

[0038] like Fig. 20 , 21 As shown, the structure of the bracket assembly 4 is that the slider 4.2 and the bracket 4.1 are injection molded as one body, and the slider 4.2 is made of wear-resistant plastic material, such as polyoxymethylene, polyetheretherketone, etc., and is molded by two-color injection molding or insert injection molding. The interior of the slider 4.2 is a waist-shaped hole composed of two semicircles and a rectangle. As shown in the figure, a rectangle with a length of a is extended in the middle of the two semicircles with a radius of R, and the radius of the guide rod 3 is R, which not only ensures that the slider 4.2 can suppress the overall movement of the components, but also allows the components to be deflected to both sides with a gap of a after assembly, effectively preventing the mechanism from getting stuck during assembly or reciprocating motion.

[0039] like Fig. 22As shown, the structure of the push rod assembly 13 is that the push rod 13.4 and the connecting rod 13.3 are riveted together, the magnet seat 13.2 and the connecting rod 13.3 are riveted together, the pressure block 13.1 and the connecting rod 13.3 are riveted together, and the permanent magnet 13.5 and the magnet seat 13.2 are connected as a whole by injection molding; because the push rod assembly 13 and the bracket assembly 4, the screw assembly 5, and the nut assembly 14 are clearance-matched, when the electronic brake booster works normally, the permanent magnet 13.5 and the displacement sensor 22 can cooperate to output signals, drive the motor to output torque, and the push rod 13.4 is used to connect the automobile brake pedal.

[0040] How it works

[0041] Different from the previous automobile brake booster products, the automobile electronic brake booster device of the present invention uses a motor as a power source to replace the original vacuum source for brake boosting.

[0042] like Figure 2 , 3 As shown, the motor outputs torque through the driving gear assembly 18, and transmits the torque to the nut assembly 14 through the reduction gear assembly 19. The first-level nut 14.2 and the second-level nut 14.3 in the nut assembly 14 are both non-self-locking threads, and the torque is transmitted to the screw assembly 5 through the threads. The screw assembly 5 and the bracket assembly 4 are connected as a whole through interference fit. Under the action of the guide rod 3, the relevant mechanism is suppressed from rotating with the gear to eliminate the radial force. At this time, the nut and screw are matched with the non-self-locking threads to convert the torque into axial thrust, that is, the motor assists the driver.

[0043] When the driver presses the pedal, Fig. 22 As shown, the pedal force causes the push rod assembly 13 to move axially, and the push rod assembly 13 is in clearance fit with the bracket assembly 4 and the screw assembly 5. Under the action of the return spring 2, the bracket assembly and the screw assembly are stationary. Since the bracket assembly 4 is connected to the displacement sensor 22 as a whole, the push rod assembly is integrated with a permanent magnet 13.5. At this time, the permanent magnet 13.5 and the displacement sensor 22 have a travel sensing displacement difference. After receiving the difference signal, the motor outputs torque to drive the reduction gear assembly 19, the nut assembly 14, and the screw assembly 5 to make the bracket assembly 4 and the displacement sensor 22 move axially; when the displacement sensor 22 moves and displaces until the signal difference is eliminated, the motor stops rotating, maintains the torque, and completes the power assistance; similarly, when the driver releases the pedal, the permanent magnet retreats, the sensor outputs a reverse displacement difference, and the motor reverses to drive the system back to its original position.

[0044] Since the nut assembly 14 includes a primary nut 14.2 and a secondary nut 14.3, which engage and slide with the screw assembly 5 through a non-self-locking thread, when the screw assembly 5 moves to the root of the primary nut 14.2, the secondary nut 14.3 can continue to engage and transmit torque, provide additional axial displacement, and increase the booster stroke. Different displacement master cylinders can be matched according to needs to meet the selection of master cylinders with different strokes.

[0045] like Fig.18 , 19 As shown, when the motor, control system or electricity fails, due to the design of N mutually meshing guide grooves between the center gear 14.1 and the secondary nut 14.3 in the nut assembly 14, the secondary nut 14.3 can be separated from the center gear 14.1 and move axially. The two can slide axially under the action of the driver's pedaling force, driving the secondary nut 14.3 and the center gear 14.1 to separate axially. At this time, the driver's pedaling force drives the screw assembly 5, the bracket assembly 4, the master cylinder push rod 10, the retaining ring 11, the feedback plate 12 and other mechanisms to move upward through the push rod assembly 13, forming a thrust, providing braking force for the entire vehicle, and finally completing braking, so that the driver can directly rely on stepping on the brake pedal to form a thrust to bring about braking, providing double protection for vehicle safety.

Claims

1. An automotive electronic brake booster device, wherein a shell cover and a guide rod are riveted to the shell, one end of the return spring is pressed on the retaining ring and the other end is pressed inside the shell cover, the main cylinder body is connected to the guide rod through a nut, the main cylinder push rod and the feedback plate are sequentially placed above the bracket assembly, the driving gear assembly and the reduction gear assembly are meshed through helical gears, the bracket assembly and the guide rod are clearance-matched, and the bracket assembly and the displacement sensor are hot-melt connected, characterized in that: The reduction gear assembly is meshed and connected with the nut assembly through the helical gears, the nut assembly is assembled in the rolling bearing, the bearing sleeve is interference riveted with the rolling bearing, the dust cover is interference sleeved on the bearing sleeve, the nut assembly is threadedly connected with the screw assembly, the support plate of the screw assembly is interference connected with the bracket assembly as a whole, the push rod assembly is clearance matched with the bracket assembly and the screw assembly respectively, the washer is welded with the bottom of the screw of the screw assembly, and the push rod spring is located between the push rod spring seat and the washer; The structure of the nut assembly is that the central gear and the secondary nut are respectively matched through the clearance of their own N guide grooves 1 and 2, the primary nut and the secondary nut are meshed through non-self-locking threads, and the head boss of the primary nut is matched and connected with the groove of the head of the secondary nut to ensure that they cannot fall out of each other.

2. The automotive electronic brake booster according to claim 1, characterized in that: The primary nut and the secondary nut are made of polypropylene, polyoxymethylene or polyetheretherketone.

3. The automotive electronic brake booster according to claim 1, characterized in that: The structure of the screw assembly is that the support plate and the screw are connected by laser welding, and the washer ensures that the screw assembly will not fall out of the primary nut after the screw assembly travels a full stroke.

4. The automotive electronic brake booster according to claim 1, characterized in that: The structure of the bracket assembly is that the slider and the bracket are injection molded as one body, the inside of the slider is a waist-shaped hole composed of two semicircles and a rectangle, the middle of the two semicircles with a radius of R is extended with a rectangle with a length of a, and the radius of the guide rod is R, so that the slider can suppress the overall movement of the components, and at the same time, the components can be deflected to both sides by a gap with a width of a after assembly.

5. The automotive electronic brake booster according to claim 4, characterized in that: The sliding block is made of wear-resistant plastic material.

6. The automotive electronic brake booster according to claim 5, characterized in that: The slider is made of polyoxymethylene or polyetheretherketone.

7. The automotive electronic brake booster according to claim 1, characterized in that: The structure of the push rod assembly is that the push rod and the connecting rod are riveted together, the magnet seat and the connecting rod are riveted together, the pressure block and the connecting rod are riveted together, and the permanent magnet and the magnet seat are connected together by injection molding.

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