Composite plunger force feedback type hydraulic pressure boosting brake pump

Abstract

A composite plunger force feedback type hydraulic pressure boosting brake pump, comprising a brake pump shell assembly, a composite plunger assembly, the composite plunger assembly is slidably arranged in the cavity of the brake pump shell assembly, the cavity of the brake pump shell assembly is divided into an oil inlet cavity, an oil return cavity and a pressure boosting cavity, the pressure difference between the oil inlet cavity and the oil return cavity is transmitted to the brake after being increased by the pressure boosting cavity, and a tractor or other vehicle is braked; the composite plunger assembly comprises a composite plunger and a force feedback plunger, the force feedback plunger is slidably arranged in the composite plunger, and the size of the hydraulic oil flow damping between the oil inlet cavity and the oil return cavity or the oil path connection between the two cavities is controlled through the sliding stroke of the force feedback plunger; the brake pump can control the stroke of the feedback control plunger by controlling the feedback force of the force feedback plunger, realize the speed reduction brake of the tractor or other motor vehicles, and also can directly make the feedback control plunger move to the position, realize the emergency brake of the tractor or other vehicles.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of power brake pump for tractor or other motor vehicle, in particular to a composite plunger force feedback type hydraulic pressure boosting brake pump. BACKGROUND

[0002] The existing hydraulic power brake pump for tractor or other motor vehicle does not have force feedback function, when the driver steps on the brake pedal during braking, the hydraulic system drives the brake pump to work, directly entering full pressure braking state, i.e. emergency braking state, the brake makes the wheels lock, so that the tractor or other motor vehicle stops running; but in the braking of tractor or other motor vehicle, most cases are to reduce the running speed of tractor or other vehicle through braking, rather than directly entering emergency braking, obviously the existing hydraulic power brake pump for tractor or other motor vehicle cannot meet this requirement; when using the existing hydraulic power brake pump to brake the tractor or other vehicle, the brake pedal needs to be repeatedly stepped on to avoid the brake from locking the wheels while achieving the purpose of reducing the speed, so the brake operation is very inconvenient, and improper operation during braking may also cause traffic safety problems. SUMMARY

[0003] In order to overcome the deficiencies in the background art, the present application discloses a composite plunger force feedback type hydraulic pressure boosting brake pump, which comprises a brake pump shell assembly and a composite plunger assembly, the composite plunger assembly is slidably arranged in the cavity of the brake pump shell assembly, and the cavity of the brake pump shell assembly is divided into an oil inlet cavity, an oil return cavity and a pressure boosting cavity; the composite plunger assembly comprises a composite plunger and a force feedback plunger, the force feedback plunger is slidably arranged in the composite plunger, and the size of the hydraulic oil flow damping between the oil inlet cavity and the oil return cavity or the oil path connection between the oil inlet cavity and the oil return cavity is controlled; when deceleration braking is performed, the driver controls the stroke of the brake pedal to control the sliding stroke of the force feedback plunger in the composite plunger, thereby controlling the size of the hydraulic oil flow damping between the oil inlet cavity and the oil return cavity, so that a pressure difference is generated between the oil inlet cavity and the oil return cavity, the pressure difference drives the composite plunger assembly to move, the pressure boosting cavity generates increased pressure, the brake drives the wheels to brake, and the wheels are prevented from being locked; when deceleration braking is performed, the pressure of the pressure boosting cavity is fed back to the force feedback plunger, so that the driver can feel the size of the braking force, and thus can accurately control the stroke of the brake pedal; when emergency braking is performed, the driver steps on the brake pedal to the end, the hydraulic oil between the oil inlet cavity and the oil return cavity is completely shut off, the pressure difference between the oil inlet cavity and the oil return cavity reaches the maximum (the pressure of the oil return cavity is zero), and the diameter difference between the large plunger and the small plunger of the composite plunger is utilized to increase the hydraulic oil pressure of the pressure boosting cavity, so as to enter the full pressure boosting braking state, the brake locks the wheels, and the purpose of emergency braking is achieved.

[0004] In order to achieve the object of the application, the application adopts the following technical solutions: a composite plunger force feedback type hydraulic pressure boosting brake pump, comprising a brake pump shell assembly and a composite plunger assembly, the composite plunger assembly being slidably arranged in a cavity of the brake pump shell assembly; the brake pump shell assembly comprises a shell and front and rear end covers fixedly arranged at both ends of the shell, wherein the inner side of the rear end cover is provided with a rear end cover oil cavity; the composite plunger assembly comprises a composite plunger and a force feedback plunger, the composite plunger being provided with a large plunger and a small plunger, the large plunger dividing the cavity of the brake pump shell assembly into an oil inlet cavity and an oil return cavity, the small plunger extending into the rear end cover oil cavity to form a pressure boosting cavity; a stepped hole is arranged in the middle of the composite plunger, the force feedback plunger being slidably arranged in the stepped hole of the composite plunger to control the size of the hydraulic oil flow damping between the oil inlet cavity and the oil return cavity or to shut off the oil path connection between the oil inlet cavity and the oil return cavity; when deceleration braking is performed, the driver controls the stroke of the brake pedal to control the sliding stroke of the force feedback plunger in the composite plunger, thereby controlling the size of the hydraulic oil flow damping between the oil inlet cavity and the oil return cavity, so that a pressure difference is generated between the oil inlet cavity and the oil return cavity, the pressure difference drives the composite plunger assembly to move, the pressure boosting cavity generates increased pressure, the hydraulic oil in the pressure boosting cavity enters the brake, drives the brake to brake the wheels, and the wheels are prevented from being locked; when deceleration braking is performed, the pressure of the pressure boosting cavity is fed back to the force feedback plunger, so that the driver can feel the size of the brake feedback force, thereby accurately controlling the stroke of the brake pedal to achieve the purpose of controlling the size of the brake force; when emergency braking is performed, the driver steps on the brake pedal to the full stroke, the force feedback plunger directly moves to the position, and the hydraulic oil connection channel between the oil inlet cavity and the oil return cavity is completely shut off, at this time, the pressure of the oil return cavity is zero, the hydraulic oil pressure of the oil inlet cavity is fully applied to the composite plunger, the diameter difference between the large plunger and the small plunger of the composite plunger is utilized to increase the hydraulic oil pressure of the pressure boosting cavity, and the full pressure boosting braking state is entered, the brake locks the wheels, and the purpose of emergency braking is achieved.

[0005] The composite plunger is correspondingly provided with a composite plunger homing spring, and the force feedback plunger is correspondingly provided with a force feedback plunger homing spring; after the homing springs are added, the composite plunger and the force feedback plunger can be more reliably homed after the composite plunger force feedback type hydraulic pressure boosting brake pump ends braking.

[0006] The small plunger is provided with a plurality of pressure relief holes, and the right end of the force feedback plunger is fixedly provided with an oil supplement one-way valve; the pressure relief holes of the small plunger are used to release the residual pressure generated by the brake due to the expansion of the hydraulic oil when the air temperature is relatively high; and the oil supplement one-way valve fixedly arranged at the right end of the force feedback plunger is used to compensate for the hydraulic oil leakage of the composite plunger force feedback type hydraulic pressure boosting brake pump itself and the brake driven thereby in the working process.

[0007] Further, the composite plunger is provided with a pressure limiting structure; when the composite plunger force feedback type hydraulic pressure boosting brake pump is working, the hydraulic oil flowing through the pump changes from a flow state to a blocked state, so that a pressure impact is generated in the pump, especially when emergency braking, the pressure impact is more obvious, which may cause damage to the pump and the brake; after adding the pressure limiting structure, the impact pressure is released through the pressure limiting structure, preventing damage to the composite plunger force feedback type hydraulic pressure boosting brake pump or the brake during emergency braking.

[0008] Further, the composite plunger and the force feedback plunger are provided with a gasket.

[0009] Further, the composite plunger and the shell and the rear end cover are provided with a gasket.

[0010] Further, the force feedback plunger and the front end cover are provided with a dustproof sealing ring and a Y-shaped sealing ring.

[0011] Due to the adoption of the technical scheme as described above, the composite plunger force feedback type hydraulic pressure boosting brake pump has the following beneficial effects: the composite plunger force feedback type hydraulic pressure boosting brake pump disclosed by the application comprises a brake pump shell assembly and a composite plunger assembly, the composite plunger assembly is slidingly arranged in the cavity of the brake pump shell assembly, and the cavity of the brake pump shell assembly is divided into an oil inlet cavity, an oil return cavity and a pressure boosting cavity; the composite plunger assembly comprises a composite plunger and a force feedback plunger, the force feedback plunger is slidingly arranged in the composite plunger, and the size of the hydraulic oil flow damping between the oil inlet cavity and the oil return cavity or the connection of the oil path between the oil inlet cavity and the oil return cavity is controlled; when deceleration braking is performed, the driver controls the sliding stroke of the force feedback plunger in the composite plunger by controlling the brake pedal stroke, thereby controlling the size of the hydraulic oil flow damping between the oil inlet cavity and the oil return cavity, generating a pressure difference between the oil inlet cavity and the oil return cavity, driving the composite plunger assembly to move, making the pressure boosting cavity generate increased pressure, and driving the brake to brake the wheels while avoiding wheel lock; when deceleration braking is performed, the pressure of the pressure boosting cavity is fed back to the force feedback plunger, so that the driver can feel the size of the braking force, and thus can accurately control the brake pedal stroke; when emergency braking is performed, the driver steps on the brake pedal to the full stroke, completely cutting off the hydraulic oil between the oil inlet cavity and the oil return cavity, increasing the hydraulic oil pressure of the pressure boosting cavity by using the diameter difference between the large plunger and the small plunger, entering the full pressure boosting braking state, and making the brake lock the wheels to achieve the purpose of emergency braking; when the composite plunger force feedback type hydraulic pressure boosting brake pump is used for deceleration braking, the driver does not need to repeatedly step on the brake pedal, but only needs to control the brake pedal stroke according to the feedback force of the brake pedal, so that the deceleration braking operation is more convenient, and the safety of deceleration braking is improved. BRIEF DESCRIPTION OF DRAWINGS

[0012] Figure 1 It is a structure schematic view of the composite plunger force feedback type hydraulic pressure boosting brake pump of embodiment one.

[0013] Figure 2 Schematic diagram of brake pump housing assembly for example one;

[0014] Figure 3 Schematic diagram of composite plunger assembly for example one;

[0015] Figure 4 Schematic diagram of composite plunger for example one;

[0016] Figure 5 Schematic diagram of force feedback plunger for example one;

[0017] Figure 6 Schematic diagram of composite plunger force feedback type hydraulic booster brake pump for example two;

[0018] Figure 7 Schematic diagram of composite plunger assembly for example two;

[0019] Figure 8 Schematic diagram of composite plunger for example two;

[0020] Figure 9 Schematic diagram of force feedback plunger for example three;

[0021] Figure 10 Schematic diagram of composite plunger assembly for example four;

[0022] Figure 11 Schematic diagram of brake pump housing assembly for example five.

[0023] In the figure: 1, brake pump housing assembly; 1.1, housing; 1.1.1, oil inlet; 1.1.2, oil return; 1.2, front end cover; 1.2.1, front end cover through hole; 1.3, rear end cover; 1.3.1, rear end cover oil cavity; 1.3.2, brake oil outlet; 2, composite plunger assembly; 2.1, composite plunger; 2.1.1, large plunger; 2.1.1.1, pressure limiting oil hole; 2.1.2, small plunger; 2.1.2.1, composite plunger oil return hole; 2.1.2.2, pressure relief hole; 2.1.3, plunger head; 2.1.3.1, plunger head oil inlet; 2.2, force feedback plunger; 2.2.1, control plunger ring groove; 2.2.2, control plunger anti-drop ring; 2.2.3, oil supplementing check valve; 2.2.4, oil supplementing hole; 2.2.6, throttling cone surface; 2.2.7, throttling hole; 2.3, force feedback plunger return spring; 2.4, return spring retainer; 2.5, pressure limiting ring; 2.6, pressure limiting spring; 2.7, pressure limiting adjusting nut; 2.8, pressure limiting disc spring; 3, composite plunger return spring; 4, oil inlet cavity; 5, oil return cavity; 6, booster cavity; 7, annular throttling port. Implementation

[0024] The application can be explained in detail by the following examples, and the purpose of the disclosure is to protect all technical improvements within the scope of the application. Examples

[0025] Referring to the drawings attached to the specification Figure 1 The composite plunger force feedback type hydraulic brake booster pump comprises a brake pump shell assembly 1, a composite plunger assembly 2, and a composite plunger return spring 3.

[0026] Referring to the drawings attached to the specification Figure 2 The brake pump shell assembly 1 comprises a shell 1.1, a front end cover 1.2 and a rear end cover 1.3 fixedly arranged at both ends of the shell 1.1; the shell 1.1 is provided with an oil inlet 1.1.1 and an oil return port 1.1.2 which are in communication with the inner cavity; the front end cover 1.2 is provided with a front end cover through hole 1.2.1 in the middle; the inner side of the rear end cover 1.3 is provided with a rear end cover oil cavity 1.3.1, and the bottom of the rear end cover oil cavity 1.3.1 is provided with a brake oil outlet 1.3.2.

[0027] Referring to the drawings attached to the specification Figure 3 The composite plunger assembly 2 comprises a composite plunger 2.1, a force feedback plunger 2.2, and a force feedback plunger return spring 2.3.

[0028] Referring to the drawings attached to the specification Figure 4 The composite plunger 2.1 is provided with a large plunger 2.1.1 and a small plunger 2.1.2, and the end face of the large plunger 2.1.1 is provided with a plunger head 2.1.3; the composite plunger 2.1 is provided with a stepped hole in the middle; the plunger head 2.1.3 is radially and uniformly provided with four plunger head oil inlet holes 2.1.3.1 which are in communication with the stepped hole around the axis; the small plunger 2.1.2 is radially and uniformly provided with four composite plunger oil return holes 2.1.2.1 which are in communication with the stepped hole around the axis near the large plunger 2.1.1; the small plunger 2.1.2 is radially and uniformly provided with four pressure relief holes 2.1.2.2 which are in communication with the stepped hole around the axis near the middle.

[0029] Referring to the drawings attached to the specification Figure 5 The force feedback plunger 2.2 is provided with a control plunger ring groove 2.2.1 on the outer circumference near the right end, and the left side of the control plunger ring groove 2.2.1 is provided with a throttling cone surface 2.2.6; the right inner side of the force feedback plunger 2.2 is fixedly provided with an oil supplementing check valve 2.2.3; the bottom of the control plunger ring groove 2.2.1 is provided with two symmetrical oil supplementing holes 2.2.4, and the control plunger ring groove 2.2.1 is unidirectionally communicated to the right end face of the force feedback plunger 2.2 through the oil supplementing holes 2.2.4, an axial hole in the middle of the force feedback plunger 2.2, and the oil supplementing check valve 2.2.3; the left side of the control plunger ring groove 2.2.1 is provided with a control plunger anti-falling ring 2.2.2.

[0030] Referring to the drawings attached to the specification Figure 3: Force feedback plunger 2.2 is slidingly arranged in the stepped hole of composite plunger 2.1, a hole spring retainer is arranged in the left stepped hole, the hole spring retainer cooperates with the control plunger anti-disengagement ring 2.2.2 to prevent force feedback plunger 2.2 from disengaging from the stepped hole of composite plunger 2.1; a return spring retainer 2.4 and a hole spring retainer are arranged in the right stepped hole, the hole spring retainer prevents return spring retainer 2.4 from disengaging from the stepped hole; force feedback plunger return spring 2.3 is arranged between oil supplementing check valve 2.2.3 and return spring retainer 2.4; in the non-working state, plunger head oil inlet hole 2.1.3.1 and composite plunger oil return hole 2.1.2.1 are communicated through the stepped hole of composite plunger 2.1 and the control plunger ring groove 2.2.1; the stepped hole of composite plunger 2.1 cooperates with the throttle cone surface 2.2.6 to form an annular throttle port 7;

[0031] Referring to the drawings Figure 1 : Composite plunger assembly 2 is slidingly arranged in the cavity of brake pump housing assembly 1; the left end of force feedback plunger 2.2 extends out of brake pump housing assembly 1 through front end cover through hole 1.2.1; in the non-working state, the left end surface of plunger head 2.1.3 abuts against front end cover 1.2; large plunger 2.1.1 divides the cavity of brake pump housing assembly 1 into oil inlet cavity 4 and oil return cavity 5; small plunger 2.1.2 extends into rear end cover oil cavity 1.3.1 to form a pressurizing cavity 6; composite plunger return spring 3 is arranged between the right end surface of large plunger 2.1.1 and the left end surface of rear end cover 1.3; in the initial state, the annular throttle port 7 has the maximum opening, and almost no damping is generated to the flow of hydraulic oil, and the pressure between oil inlet cavity 4 and oil return cavity 5 is equal;

[0032] Oil inlet 1.1.1 is connected with the hydraulic system of a tractor or other motor vehicle through a hydraulic pipeline, oil return port 1.1.2 is connected with the oil tank of the hydraulic system of a tractor or other motor vehicle through a hydraulic pipeline, and brake oil outlet 1.3.2 is connected with the brake of a tractor or other motor vehicle through a hydraulic pipeline; in the non-braking state of a tractor or other motor vehicle, the hydraulic oil entering the composite plunger force feedback type hydraulic pressure boosting brake pump through oil inlet 1.1.1 first enters oil inlet cavity 4, flows into oil return cavity 5 through annular throttle port 7 and composite plunger oil return hole 2.1.2.1, and then flows back to the oil tank of the hydraulic system through oil return port 1.1.2; at this time, there is no pressure difference between the left and right end surfaces of large plunger 2.1.1, and composite plunger 2.1 remains in place;

[0033] When the tractor or other motor vehicle is decelerating, the driver steps on the brake pedal, the force feedback plunger 2.2 moves to the right, the throttle taper 2.2.6 gradually enters the small hole of the stepped hole of the composite plunger 2.1, the opening of the annular throttle 7 becomes smaller, at this time the pressure drop occurs when the hydraulic oil flows through the annular throttle 7, so that the pressure difference between the oil inlet cavity 4 and the oil return cavity 5 on the left and right sides of the large plunger 2.1.1 is generated, and the pressure difference drives the composite plunger 2.1 to move to the right; When the composite plunger 2.1 moves to the right, the small plunger 2.1.2 in the rear cover oil cavity 1.3.1 moves to the right, the volume of the pressure boosting cavity 6 becomes smaller, the pressure rises, and the increased pressure is related to the ratio of the effective area of the large plunger 2.1.1 and the effective area of the small plunger 2.1.2. The pressure difference between the oil inlet cavity 4 and the oil return cavity 5 is boosted; The hydraulic oil in the pressure boosting cavity 6 enters the brake under the action of the boosted pressure, generating braking; When decelerating, the pressure in the pressure boosting cavity 6 also acts on the right end face of the force feedback plunger 2.2, forming force feedback, so that the driver can feel the size of the brake feedback force, and then the driver controls the stroke of the brake pedal according to the size of the feedback force, so as to control the size of the braking force; During deceleration, if emergency braking is required, the driver increases the force of stepping on the brake pedal, at this time, due to the small area of the feedback control plunger 2.2, the pressure in the pressure boosting cavity 6 will continue to increase, and the pressure in the pressure boosting cavity 6 is greater than the pressure difference between the oil inlet cavity 4 and the oil return cavity 5. Therefore, the composite plunger 2.1 will move to the left under the action of the pressure in the pressure boosting cavity 6, and finally the annular throttle 7 is completely closed, and the oil path between the oil inlet cavity 4 and the oil return cavity 5 is completely shut off. At this time, the pressure in the oil return cavity 5 is zero, and the hydraulic oil pressure in the oil inlet cavity 4 acts on the left end face of the large plunger 2.1.1, and the composite plunger 2.1 increases the hydraulic oil pressure in the pressure boosting cavity 6 by using the diameter difference between the large plunger 2.1.1 and the small plunger 2.1.2, so as to enter the full pressure boosting braking state, and the hydraulic oil in the pressure boosting cavity 6 rapidly enters the brake under the action of the pressure after full pressure boosting, so as to lock the wheels of the brake, achieving the purpose of emergency braking;

[0034] When the driver needs to directly enter the emergency braking, the driver steps on the brake pedal quickly, the force feedback control plunger 2.2 moves to the right quickly, the annular throttle 7 closes quickly, the oil path connection between the inlet oil chamber 4 and the return oil chamber 5 is directly completely closed, at this time the pressure of the return oil chamber 5 is zero, the hydraulic oil pressure of the inlet oil chamber 4 acts on the left end face of the large plunger 2.1.1, the composite plunger 2.1 is pushed to move to the right quickly, the small plunger 2.1.2 in the rear end cover oil chamber 1.3.1 moves to the right quickly, the volume of the pressure boosting chamber 6 becomes smaller, the pressure rises, at the same time, due to the diameter difference between the composite plunger 2.1 and the large plunger 2.1.1 and the small plunger 2.1.2, the pressure of the pressure boosting chamber 6 boosts the pressure of the inlet oil chamber 4, enters the full pressure boosting braking state, the hydraulic oil in the pressure boosting chamber 6 enters the brake under the action of the pressure after boosting, the brake locks the wheels, and the purpose of emergency braking is achieved;

[0035] Under normal circumstances, after the braking is completed, the driver releases the brake pedal, the hydraulic oil in the brake returns to the pressure boosting chamber 6 under the action of the return spring, and the composite plunger 2.1 and the force feedback plunger 2.2 return to the original position under the action of the hydraulic oil returning in the pressure boosting chamber 6 and the return spring; however, when there is a hydraulic oil leakage problem in the composite plunger force feedback type hydraulic pressure boosting brake pump itself and the brake driven thereby, the hydraulic oil returning in the pressure boosting chamber 6 is not enough to completely return the composite plunger 2.1 and the force feedback plunger 2.2 to the original position; at this time, the hydraulic oil in the return oil chamber 5 enters the stepped hole of the composite plunger 2.1 (i.e. enters the pressure boosting chamber 6) through the pressure relief hole 2.1.2.2, compensates for the hydraulic oil leakage of the composite plunger force feedback type hydraulic pressure boosting brake pump itself and the brake driven thereby, and ensures that the composite plunger 2.1 and the force feedback plunger 2.2 completely return to the original position;

[0036] In addition, during the returning process of the composite plunger 2.1 and the force feedback plunger 2.2, the composite plunger 2.1 and the force feedback plunger 2.2 return out of synchronization, causing the pressure relief hole 2.1.2.2 to be blocked by the force feedback plunger 2.2, at this time, the composite plunger 2.1 and the force feedback control plunger 2.2 have a tendency to move to the left under the action of the composite plunger return spring 3 and the force feedback control plunger return spring 8, the tendency causes the pressure boosting chamber 6 to generate negative pressure, the pressure of the return oil chamber 5 is greater than the pressure of the pressure boosting chamber 6, the oil supplementing one-way valve 2.2.3 is opened under the pressure difference between the return oil chamber 5 and the pressure boosting chamber 6, the hydraulic oil of the return oil chamber 5 enters the pressure boosting chamber 6, and compensates for the hydraulic oil leakage of the brake force feedback hydraulic pressure boosting brake pump itself and the brake driven thereby;

[0037] In summer, when the ambient temperature rises, the hydraulic oil in the brake will expand, the expanded hydraulic oil will generate residual pressure in the brake, the residual pressure will cause the brake caliper piston to return incompletely, and the friction plate of the tractor or other motor vehicles will be in a friction state for a long time; when the hydraulic oil in the brake expands, the expanded hydraulic oil enters the booster chamber 6, and then enters the oil return chamber 5 through the pressure relief hole 2.1.2.2, so that the residual pressure of the brake is released. Embodiment

[0038] Referring to the accompanying drawings Figure 6 In this embodiment, a pressure limiting structure is arranged on the composite plunger 2.1; the specific structure is: referring to the accompanying drawings Figure 7 The composite plunger 2.1 further comprises a pressure limiting ring 2.5, a pressure limiting spring 2.6, and a pressure limiting adjusting nut 2.7; referring to the accompanying drawings Figure 8 At the same time, six through pressure limiting oil holes 2.1.1.1 are uniformly arranged on the end face of the large plunger 2.1.1 around the axis; referring to the accompanying drawings Figure 7 The pressure limiting ring 2.5 is arranged on the right end face of the large plunger 2.1.1, the pressure limiting spring 2.6 is arranged on the right side of the pressure limiting ring 2.5, and the pressure limiting adjusting nut 2.7 is arranged on the right side of the pressure limiting spring 2.6. The pressure limiting adjusting nut 2.7 is connected with the composite plunger 2.1 through the threads arranged on the outer circumference of the small plunger 2.1.2. The pressure limiting adjusting nut 2.7 exerts a pre-press on the pressure limiting spring 2.6, and the pre-press can be adjusted by adjusting the pressure limiting adjusting nut 2.7. The pre-press determines the pressure limiting pressure of the pressure limiting structure;

[0039] When the composite plunger force feedback type hydraulic booster brake pump is working, especially when emergency braking is performed, the hydraulic oil flowing through the pump will change from a flow-through state to a blocked state rapidly, so that a pressure shock will be generated in the pump body, the pressure of the oil inlet chamber 4 will instantaneously increase greatly (exceeding the input pressure of the hydraulic system), and the pressure of the oil inlet chamber 4 will become higher after being boosted by the booster chamber 6, so that the composite plunger force feedback type hydraulic booster brake pump is prone to be damaged. At the same time, the great pressure of the booster chamber 6 is transmitted to the brake, so that the brake is also prone to be damaged. After the pressure limiting structure is added, when the pressure of the oil inlet chamber 4 instantaneously increases, the pressure will be transmitted to the pressure limiting ring 2.5 through the pressure limiting oil holes 2.1.1.1, the pressure limiting ring 2.5 compresses the pressure limiting spring 2.6, so that the pressure limiting ring 2.5 is separated from the right end face of the large plunger 2.1.1. Therefore, the oil inlet chamber 4 and the oil return chamber 5 are communicated through the pressure limiting oil holes 2.1.1.1, and the instantaneously high pressure of the oil inlet chamber 4 is released, so that the pressure shock during emergency braking is greatly improved, and the problem that the composite plunger force feedback type hydraulic booster brake pump and the brake are damaged due to the excessively high pressure during emergency braking is prevented. Embodiment

[0040] Referring to the accompanying drawings Figure 9In this embodiment, a throttle hole 2.2.7 is arranged on the left side of the control plunger ring groove 2.2.1 in the force feedback plunger 2.2, and an oil supplement hole 2.2.4 is arranged at the bottom of the control plunger ring groove 2.2.1, and the throttle hole 2.2.7 and the oil supplement hole 2.2.4 are communicated through an axial hole;

[0041] In the braking process, by controlling the distance of the right movement of the force feedback plunger 2.2, the throttle area of the throttle hole 2.2.7 is controlled, and then the size of the hydraulic oil flow damping between the oil inlet cavity and the oil return cavity or the oil path connection between the oil inlet cavity and the oil return cavity is turned off. Embodiment

[0042] Referring to the attached drawings of the specification 10, in this embodiment, the pressure limiting spring 2.6 in the first or second embodiment is replaced by a pressure limiting disc spring 2.8; the adjusting nut 2.7 applies a pre-press to the pressure limiting disc spring 2.8, and the pre-press size determines the pressure limiting pressure;

[0043] In addition, in this embodiment, the pressure limiting disc spring 2.8 can also be a slotted disc spring, and the adjusting nut 2.7 applies a pre-press to the slotted disc spring, so that the slotted disc spring works in the linear working area, and the pressure limiting pressure of this pressure limiting structure is determined by the linear working area characteristics of the slotted disc spring. Embodiment

[0044] Referring to the attached drawings of the specification Figure 11 In this embodiment, the shell 1.1 and the front end cover 1.2 are integrated by welding; or the shell 1.1 and the front end cover 1.2 are integrated by casting.

[0045] The dynamic sealing structure of the composite plunger force feedback type hydraulic pressure boosting brake pump is that a gasket is arranged between the sealing composite plunger 2.1 and the force feedback plunger 2.2; a gasket is arranged between the composite plunger 2.1 and the shell 1.1 and the rear end cover 1.3; and a dustproof sealing ring and a Y-shaped sealing ring are arranged between the force feedback plunger 2.2 and the front end cover 1.2.

[0046] The part not described in detail in the present application is prior art.

Claims

1. A composite plunger force feedback type hydraulic booster brake pump, comprising a brake pump housing assembly (1) and a composite plunger assembly (2), wherein the composite plunger assembly (2) is slidably disposed in the cavity of the brake pump housing assembly (1); characterized in that: The brake pump housing assembly (1) includes a housing (1.1) and a front end cover (1.2) and a rear end cover (1.3) fixedly disposed at both ends of the housing (1.1), wherein the rear end cover (1.3) is provided with a rear end cover oil chamber (1.3.1) inside; the composite plunger assembly (2) includes a composite plunger (2.1) and a force feedback plunger (2.2), the composite plunger (2.1) is provided with a large plunger (2.1.1) and a small plunger (2.1.2), the large plunger (2.1.1) divides the cavity of the brake pump housing assembly (1) into an oil inlet chamber (4) and an oil return chamber (5), and the small plunger (2.1.2) extends into the rear end cover oil chamber (1.3.1) to form a booster chamber (6); The composite plunger (2.1) has a stepped hole in the middle, and the force feedback plunger (2.2) is slidably set in the stepped hole of the composite plunger (2.1) to control the magnitude of the hydraulic oil flow damping between the oil inlet chamber (4) and the oil return chamber (5) or to shut off the oil circuit connection between the oil inlet chamber (4) and the oil return chamber (5). The composite plunger (2.1) is equipped with a composite plunger return spring (3); the force feedback plunger (2.2) is equipped with a force feedback plunger return spring (2.3). The small plunger (2.1.2) is provided with several pressure relief holes (2.1.2.2), and a replenishing oil check valve (2.2.3) is fixedly installed on the right end of the force feedback plunger (2.2).

2. The composite plunger force feedback hydraulic booster brake pump according to claim 1, characterized in that: A pressure limiting structure is provided on the composite plunger (2.1).

3. The composite plunger force feedback hydraulic booster brake pump according to claim 1, characterized in that: The front cover (1.2) and the shell (1.1) are an integrated structure.

4. The composite plunger force feedback hydraulic booster brake pump according to claim 1, characterized in that: A Glyd ring is provided between the composite plunger (2.1) and the force feedback plunger (2.2).

5. The composite plunger force feedback hydraulic booster brake pump according to claim 1, characterized in that: A Gladius ring is provided between the composite plunger (2.1) and the housing (1.1) and the rear end cover (1.3).

6. The composite plunger force feedback hydraulic booster brake pump according to claim 1, characterized in that: A dustproof sealing ring and a Y-shaped sealing ring are provided between the force feedback plunger (2.2) and the front end cover (1.2).

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