Hydraulic braking system of backhoe loader

Abstract

The utility model discloses a hydraulic brake system of a backhoe loader, which relates to the technical field of excavator accessory installation and comprises a rear drive axle, a hydraulic oil tank, an energy storage device, a first single-loop foot brake valve and a second single-loop foot brake valve. An energy storage device is arranged on the oil inlet pipeline and connected with the hydraulic oil tank to supply oil to the system. The first single-loop foot brake valve is connected with a left brake disc of a rear drive axle through a first oil outlet pipeline, and the second single-loop foot brake valve is connected with a right brake disc of the rear drive axle through a second oil outlet pipeline. The energy storage device is arranged for pressure maintaining and oil storage, after a vehicle suddenly stops, oil in the energy storage device can be used for supplying oil to meet the follow-up braking requirement, multiple times of braking after the vehicle suddenly stops can be achieved, response is rapid and reliable, the service braking stability of the backhoe loader is greatly improved, and the safety performance is improved.

Description

TECHNICAL FIELD

[0001] The utility model relates to excavator loading machine driving brake technical field, concretely relates to a kind of excavator loading machine hydraulic brake systems. BACKGROUND

[0002] The existing excavator loading machine brake system mainly includes double-cavity hydraulic booster, gearbox lubrication pump and the left and right brake discs of rear drive axle, in working process, as shown in Figure 1 Power is provided using gearbox lubrication pump (04), and double-cavity hydraulic booster (01) is used as control element, when stepping on foot pedal one (02) and foot pedal two (03) of double-cavity hydraulic booster (01);Pressure oil provided by gearbox lubrication pump (04) reaches the left and right brake discs of rear drive axle through oil outlet pipeline one and oil outlet pipeline two, to realize vehicle braking;When vehicle quickly turns left, only foot pedal one (02) can be stepped on, and steering of steering wheel is cooperated, to control vehicle to quickly turn left;When vehicle quickly turns right, only foot pedal two (03) can be stepped on, and steering of steering wheel is cooperated, to control vehicle to quickly turn right, and its control principle is as shown in Figure 1 .

[0003] This brake system is prone to oil leakage in double-cavity hydraulic booster after vehicle shutdown, and after re-starting, the first braking will preferentially supplement the leaked oil in double-cavity hydraulic booster, so that the first braking after starting is not rapid and sensitive enough, affecting braking safety.Moreover, in the case of sudden vehicle shutdown, the oil in double-cavity hydraulic booster will be insufficient, unable to meet the demand of multiple braking, resulting in safety hazard in subsequent driving braking of excavator loading machine. UTILITY MODEL CONTENTS

[0004] In view of the deficiencies in the prior art, the utility model provides a kind of excavator loading machine hydraulic brake system, one or more technical problems in prior art can be solved.

[0005] To achieve the above purpose, the utility model adopts the following technical solutions:

[0006] A kind of excavator loading machine hydraulic brake system, including rear drive axle, hydraulic oil tank, energy storage device, single loop foot brake valve one and single loop foot brake valve two, the single loop foot brake valve one and single loop foot brake valve two connect same oil inlet pipeline, the energy storage device is equipped on the oil inlet pipeline, the energy storage device is connected with the hydraulic oil tank, and oil is supplied for system;The left brake disc of rear drive axle is connected by the oil outlet pipeline one of single loop foot brake valve one, and the right brake disc of rear drive axle is connected by the oil outlet pipeline two of single loop foot brake valve two;

[0007] When the vehicle brakes, the pedals of the single-circuit foot brake valve one and the single-circuit foot brake valve two are pressed down at the same time, and the oil in the energy storage device reaches the rear drive axle through the oil outlet pipeline one and the oil outlet pipeline two;

[0008] When the vehicle turns, the pedals of the single-circuit foot brake valve one or the single-circuit foot brake valve two are pressed down alone, and unilateral braking and turning are performed.

[0009] As a further implementation, the single-circuit foot brake valve one and the single-circuit foot brake valve two are both three-position three-way valves, including an oil inlet, an oil outlet, and an oil return, and the oil return is connected to the hydraulic oil tank.

[0010] As a further implementation, the energy storage device includes a check valve and an accumulator connected in series, the output end of the check valve communicates with the accumulator, and the output end of the check valve is connected to the oil inlets of the single-circuit foot brake valve one and the single-circuit foot brake valve two; the check valve plays a pressure maintaining role, and after the vehicle suddenly stops, the oil in the accumulator can meet multiple braking requirements, greatly improving the stability of the on-road braking of the excavator loader and enhancing the safety performance.

[0011] As a further implementation, the power device for supplying oil to the energy storage device is also provided on the oil inlet pipeline, and the power device includes an engine and a gear pump, the output end of the engine is connected to the gear pump, and the gear pump is connected between the hydraulic oil tank and the oil inlet pipeline.

[0012] As a further implementation, the gear pump is connected in parallel with an overflow valve, and when the accumulator exceeds the set pressure of the overflow valve, the excess oil overflows into the hydraulic oil tank.

[0013] A hydraulic braking system for an excavator loader includes a rear drive axle, a hydraulic oil tank, an energy storage device, a double-circuit foot brake valve, an electromagnetic valve one, and an electromagnetic valve two, the energy storage device is provided on the oil inlet pipeline of the double-circuit foot brake valve, and the energy storage device is connected to the hydraulic oil tank to supply oil to the system;

[0014] The double-circuit foot brake valve is connected to the left brake disc and the right brake disc of the rear drive axle through the oil outlet pipeline one and the oil outlet pipeline two, the electromagnetic valve one is provided on the oil outlet pipeline one, and the electromagnetic valve two is provided on the oil outlet pipeline two;

[0015] When the vehicle brakes, the pedal of the double-circuit foot brake valve is pressed down, and the oil in the energy storage device reaches the rear drive axle through the oil outlet pipeline one and the oil outlet pipeline two;

[0016] When the vehicle turns, the electromagnetic valve one or the electromagnetic valve two is controlled alone, and unilateral braking and turning are performed.

[0017] As a further implementation manner, the double-circuit foot brake valve adopts a six-position six-way valve, and oil paths of brake discs on left and right sides of the rear drive axle can be simultaneously controlled.

[0018] As a further implementation manner, the energy storage device comprises a check valve and an accumulator connected in series, an output end of the check valve is communicated with the accumulator, and the output end of the check valve is connected to oil inlets of the single-circuit foot brake valve one and the single-circuit foot brake valve two; the check valve plays a pressure maintaining role, oil in the accumulator can meet brake requirements for multiple times after sudden stop of the vehicle, the stability of the travel brake of the excavator loader is greatly improved, and the safety performance is improved.

[0019] As a further implementation manner, the power device for supplying oil to the energy storage device is further arranged on the oil inlet pipeline, the power device comprises an engine and a gear pump, an output end of the engine is connected to the gear pump, and the gear pump is connected between the hydraulic oil tank and the oil inlet pipeline.

[0020] As a further implementation manner, the gear pump is connected in parallel with an overflow valve, and when the accumulator exceeds the set pressure of the overflow valve, the excessive oil overflows into the hydraulic oil tank.

[0021] By adopting the technical scheme, the excavator loader has the following beneficial effects:

[0022] 1. The energy storage device is arranged to maintain pressure and store oil, and after sudden stop of the vehicle, the subsequent brake requirement can be met by using oil in the accumulator, multiple braking after sudden stop of the vehicle can be realized, response is rapid and reliable, the stability of the travel brake of the excavator loader is greatly improved, and the safety performance is improved.

[0023] 2. Two single-circuit foot brake valves are arranged in the utility model to replace the double-cavity hydraulic booster in the prior art, selective simultaneous braking and separate braking of brake discs on left and right sides of the rear drive axle are realized, braking is performed through on-off of the pipeline, the defect that the first brake reaction is not sensitive after stop and restart of the double-cavity hydraulic booster due to oil leakage is overcome, and the safety of the overall braking system is further improved.

[0024] 3. One double-circuit foot brake valve and two electromagnetic valves are arranged in the utility model to realize selective simultaneous braking and separate braking of brake discs on left and right sides of the rear drive axle, the double-cavity hydraulic booster in the prior art is replaced, not only the defect that the first brake reaction is not sensitive is overcome, but also the control scheme is optimized compared with the control scheme of two single-circuit foot brake valves, both sides of the pedal do not need to be stepped on during braking of the vehicle, and the driver is facilitated to control.

[0025] 4、The utility model discloses a one-way valve and energy accumulator combination realize, and through engine and gear pump pressurization oil liquid in hydraulic oil tank, make oil liquid flow into energy accumulator in one-way valve and store temporarily, utilize the pressure -maintaining effect of one-way valve, and the oil liquid in energy accumulator can satisfy the demand of multiple braking after the sudden stop of vehicle. BRIEF DESCRIPTION OF DRAWINGS

[0026] The description and drawings of the utility model constitute a part of the utility model and are used to provide further understanding on the utility model, and the illustrative embodiment of the utility model and its description are used to explain the utility model, and do not constitute improper limitation on the utility model.

[0027] Figure 1 It is braking system control principle diagram for existing excavator loader;

[0028] Figure 2 It is braking system structure schematic diagram in the utility model embodiment one.

[0029] Figure 3 It is braking system structure schematic diagram in the utility model embodiment two.

[0030] In the drawing: 01, double cavity hydraulic booster;02, footboard one;03, footboard two;04, gearbox lubrication pump;

[0031] 1, rear drive axle;2, gearbox;3, front drive axle;4, overflow valve;5, hydraulic oil tank;6, gear pump;7, engine;8, one-way valve;9, energy accumulator;10, oil outlet pipeline one;11, oil outlet pipeline two;12, single circuit foot brake valve one;13, single circuit foot brake valve two;14, double circuit foot brake valve;15, electromagnetic valve one;16, electromagnetic valve two. DETAILED DESCRIPTION

[0032] It should be noted that the following detailed description is all exemplary, and aims at providing further explanation on the utility model. Unless otherwise indicated, all the technical and scientific terms used in the utility model have the same meaning as that understood by the ordinary skilled in the art to which the utility model belongs.

[0033] It should be noted that the terms used here are only for describing the specific embodiment, and are not intended to limit the exemplary embodiment according to the utility model. As used herein, unless the context clearly indicates otherwise, the singular form is intended to include the plural form, and furthermore, it should be understood that when the terms "comprise" and / or "include" are used in the specification, it means that the features, steps, operations, devices, components and / or their combinations exist. Based on the embodiments in the utility model, all other embodiments obtained by the ordinary skilled in the art without creative labor are within the scope of protection of the utility model.

[0034] Example 1

[0035] In one typical embodiment of this application, a hydraulic braking system for an excavator loader is provided, such as... Figure 2 As shown, the system includes a rear drive axle 1, a hydraulic oil tank 5, an energy storage device, a single-circuit foot brake valve 12, and a single-circuit foot brake valve 13. The single-circuit foot brake valve 12 and the single-circuit foot brake valve 13 are connected to the same oil inlet pipe. The energy storage device is installed on the oil inlet pipe and is connected to the hydraulic oil tank 5 to supply oil to the system. The single-circuit foot brake valve 12 is connected to the left brake disc of the rear drive axle 1 through an oil outlet pipe 10, and the single-circuit foot brake valve 13 is connected to the right brake disc of the rear drive axle 1 through an oil outlet pipe 11.

[0036] When the vehicle brakes, the pedals of single-circuit foot brake valve 12 and single-circuit foot brake valve 23 are pressed at the same time, and the oil in the energy storage device reaches the rear drive axle through oil outlet line 10 and oil outlet line 21.

[0037] When the vehicle is turning, press the pedal of either single-circuit foot brake valve 12 or single-circuit foot brake valve 23 separately to brake and turn on one side.

[0038] like Figure 2 As shown, a gearbox 2 is mounted on the frame between the rear drive axle 1 and the front drive axle 2 of the excavator loader. The overall braking of the excavator loader is achieved through the rear drive axle 1. Specifically, a left brake disc and a right brake disc are respectively located at the wheels on the left and right sides of the rear drive axle 1. The left brake disc is connected to a single-circuit foot brake valve 12 via an oil outlet pipe 10, and the right brake disc is connected to a single-circuit foot brake valve 23 via an oil outlet pipe 21. In this embodiment, both the single-circuit foot brake valve 1 and the single-circuit foot brake valve 2 are three-position three-way valves, such as... Figure 2 As shown, it includes an oil inlet P, an oil outlet A, and an oil return port T, wherein the oil return port T is connected to the hydraulic oil tank 5.

[0039] Specifically, single-circuit foot brake valve 12 and single-circuit foot brake valve 13 are connected in parallel to the same oil inlet pipe. A hydraulic oil tank 5 is connected to the end of the oil inlet pipe. To ensure braking performance after the excavator loader suddenly stops, an energy storage device is installed on the oil inlet pipe. For example... Figure 2 As shown, the energy storage device includes a one-way valve 8 and an accumulator 9 connected in series. The output end of the one-way valve 8 is connected to the accumulator 9, and the output end of the one-way valve 8 is connected to the oil inlet of the single-circuit foot brake valve 12 and the single-circuit foot brake valve 23. The one-way valve 8 plays a pressure-holding role. After the vehicle suddenly stops, the oil in the accumulator can meet the braking needs multiple times, which greatly improves the stability of the excavator loader's driving brake and enhances its safety performance.

[0040] Specifically, the oil inlet pipeline is further provided with a power device for supplying oil to the energy storage device, as shown in Figure 2 The power device is connected with the input end of the one-way valve 8, and the power device comprises an engine 7 and a gear pump 6. The output end of the engine 7 is connected with the gear pump 6. The gear pump 6 is connected between the hydraulic oil tank 5 and the one-way valve 8. After the vehicle starts, the engine can drive the gear pump to pressurize the oil in the hydraulic oil tank, so that part of the oil is stored in the energy accumulator after passing through the one-way valve, and the oil in the energy accumulator is used to supply oil to the brake system of the rear drive axle.

[0041] In this embodiment, as shown in Figure 2 The gear pump 6 is further connected in parallel with a relief valve 4. When the pressure in the energy accumulator 9 exceeds the set pressure of the relief valve 4, the excess oil is overflowed to the hydraulic oil tank 5, so as to ensure the stability of the pressure in the energy accumulator 9. The relief valve can protect the hydraulic system and prevent the gear pump from being damaged due to overpressure.

[0042] The working principle of this embodiment is as follows:

[0043] After the vehicle starts, the engine 7 can drive the gear pump 6 to pressurize the oil in the hydraulic oil tank 5, so that part of the oil is stored in the energy accumulator 9 after passing through the one-way valve 8, and the oil in the energy accumulator is used to supply oil to the brake system of the rear drive axle. When the pressure in the energy accumulator 9 exceeds the set pressure of the relief valve 4, the excess oil is overflowed to the hydraulic oil tank 5.

[0044] When the vehicle brakes, the pedals of the single-circuit foot brake valve one 12 and the single-circuit foot brake valve two 13 are pressed at the same time, and the oil in the energy accumulator 9 is rapidly supplied to the rear drive axle 1 through the oil outlet pipeline one 10 and the oil outlet pipeline two 11, so as to realize rapid braking;

[0045] After the vehicle suddenly stops, the oil in the energy accumulator 9 can supply oil to the rear drive axle 1 due to the pressure maintaining effect of the one-way valve 8, so as to realize subsequent braking requirements;

[0046] When the vehicle quickly turns left, only the single-circuit foot brake valve one 12 is pressed, and the steering of the vehicle is realized by cooperating with the steering of the steering wheel. When the vehicle quickly turns right, only the single-circuit foot brake valve two 13 is pressed, and the steering of the vehicle is realized by cooperating with the steering of the steering wheel.

[0047] Embodiment two

[0048] In the technical solution of the first embodiment, two single-circuit foot brake valves need to be controlled to be pressed at the same time during braking. In another preferred embodiment of the present application, the control process can be optimized, as shown in Figure 3As shown, the brake system of the embodiment comprises a rear drive axle 1, a hydraulic oil tank 5, an energy storage device, a double-circuit foot brake valve 14, an electromagnetic valve 15 and an electromagnetic valve 16, the energy storage device is arranged on the oil inlet pipeline of the double-circuit foot brake valve 14, and the energy storage device is connected with the hydraulic oil tank 5 to supply oil for the system.

[0049] The double-circuit foot brake valve 14 is connected with the left brake disc and the right brake disc of the rear drive axle 1 through an oil outlet pipeline 10 and an oil outlet pipeline 11, the electromagnetic valve 15 is arranged on the oil outlet pipeline 10, and the electromagnetic valve 16 is arranged on the oil outlet pipeline 11.

[0050] When the vehicle brakes, the pedal of the double-circuit foot brake valve 14 is stepped on, and the oil in the energy storage device reaches the rear drive axle 1 through the oil outlet pipeline 10 and the oil outlet pipeline 11.

[0051] When the vehicle turns, the electromagnetic valve 15 or the electromagnetic valve 16 is controlled alone to brake and turn on one side.

[0052] As shown, Figure 3 The transmission 2 is arranged on the frame between the rear drive axle 1 and the front drive axle 3 of the excavator loader, and the overall braking of the excavator loader is realized through the rear drive axle. Specifically, the left brake disc and the right brake disc are arranged at the wheels on the left side and the right side of the rear drive axle 1 respectively, and the brake disc and the right brake disc are connected with the oil outlet pipeline 10 and the oil outlet pipeline 11 of the double-circuit foot brake valve 14 respectively. In the embodiment, the double-circuit foot brake valve is a six-position six-way valve, which can control the oil paths of the brake discs on the left side and the right side of the rear drive axle at the same time.

[0053] Specifically, as shown, Figure 3 The oil inlet pipeline of the double-circuit foot brake valve 14 is connected with the oil inlet pipeline, and the hydraulic oil tank 5 is arranged at the end of the oil inlet pipeline. In order to ensure the braking performance of the excavator loader after sudden stop, the energy storage device is arranged on the oil inlet pipeline. As shown, Figure 2 The energy storage device comprises a check valve 8 and an accumulator 9 connected in series, the output end of the check valve 8 communicates with the accumulator 9, and the output end of the check valve 8 is connected to the oil inlet of the double-circuit foot brake valve 14; the check valve plays a pressure maintaining role, and the oil in the accumulator can realize multiple braking requirements after the vehicle suddenly stops, greatly improving the stability of the service braking of the excavator loader and improving the safety performance.

[0054] Specifically, the power device for supplying oil for the energy storage device is further arranged on the oil inlet pipeline, as shown, Figure 3As shown, the power device is connected with the input end of the one-way valve 8, and the power device includes the engine 7 and the gear pump 6, the output end of the engine 7 is connected with the gear pump 6, and the gear pump 6 is connected between the hydraulic oil tank 5 and the one-way valve 5, after the vehicle starts, the engine can drive the gear pump to pressurize the oil in the hydraulic oil tank, so that part of the oil is saved in the accumulator after passing through the one-way valve, and the oil in the accumulator is used to supply oil for the brake system of the rear drive axle.

[0055] In this embodiment, as shown in the figure, Figure 2 The gear pump 6 is also connected with the overflow valve 4 in parallel, when the accumulator 9 exceeds the set pressure of the overflow valve 4, the excess oil overflows to the hydraulic oil tank 5, so as to ensure the stability of the pressure in the accumulator 9, and the overflow valve can protect the hydraulic system and prevent the system from being damaged due to overpressure.

[0056] The working principle of this embodiment is as follows:

[0057] After the vehicle starts, the engine 7 drives the gear pump 6 to pressurize the oil in the hydraulic oil tank 5, and the oil is saved in the accumulator 9 after passing through the one-way valve 8, when the pressure of the accumulator 9 exceeds the set pressure of the overflow valve 4, the excess oil overflows to the hydraulic oil tank 5;

[0058] When the vehicle brakes, the pedal of the double-circuit foot brake valve 14 is stepped on, and the oil in the accumulator 9 rapidly reaches the rear drive axle 1 through the oil outlet pipeline II 11 and the oil outlet pipeline I 10, so as to realize rapid braking;

[0059] After the vehicle suddenly stops, due to the pressure maintaining effect of the one-way valve 8, the oil in the accumulator 9 can meet the braking demand for multiple times;

[0060] When the vehicle quickly turns left, the control solenoid valve II 16 is powered on, at this time, the oil in the oil outlet pipeline II 11 is cut off, and only the oil in the oil outlet pipeline I 10 is output to brake when the pedal of the double-circuit foot brake valve 14 is stepped on, and the steering of the steering wheel can be used to control the vehicle to quickly turn left;

[0061] When the vehicle quickly turns right, the control solenoid valve I 15 is powered on, at this time, the oil in the oil outlet pipeline I 10 is cut off, and only the oil in the oil outlet pipeline II 11 is output to brake when the pedal of the double-circuit foot brake valve 14 is stepped on, and the steering of the steering wheel can be used to control the vehicle to quickly turn right.

[0062] Compared with the first embodiment, the control mode is optimized, the pedal of the double-circuit foot brake valve can control the left brake disc and the right brake disc of the drive axle at the same time when the vehicle brakes, and when steering, one-side deceleration or braking is needed, the control solenoid valve I or the control solenoid valve II can be pressed to control the vehicle to quickly turn left or right, and the pedal of the double-circuit foot brake valve can be stepped on at any time to deal with emergency braking, which is convenient for the driver to operate and further ensures the safety of the vehicle brake system.

[0063] The above merely describes preferred embodiments of the present application and is not intended to limit the present application. For those skilled in the art, the present application can have various modifications and changes. Any modification, equivalent replacement, improvement, etc. made within the spirit and principle of the present application shall be included in the protection scope of the present application.

Claims

1. An excavator loader hydraulic braking system characterized by, The application relates to a single-circuit foot brake valve and a double-circuit foot brake valve. When the vehicle brakes, the pedals of the single-circuit foot brake valve and the double-circuit foot brake valve are pressed simultaneously, and the oil in the energy storage device reaches the rear drive axle through the oil outlet pipelines. When the vehicle turns, the pedals of the single-circuit foot brake valve and the double-circuit foot brake valve are pressed separately, and unilateral braking and turning are realized.

2. An excavator hydraulic brake system as claimed in claim 1, wherein, The single-circuit foot brake valve and the double-circuit foot brake valve are all three-position three-way valves, which comprise an oil inlet, an oil outlet and an oil return, and the oil return is connected with the hydraulic oil tank.

3. An excavator hydraulic brake system as claimed in claim 1, wherein, The energy storage device comprises a check valve and an accumulator which are connected in series, and the output end of the check valve is communicated with the accumulator and connected with the oil inlets of the single-circuit foot brake valve and the double-circuit foot brake valve.

4. An excavator hydraulic brake system as claimed in claim 3, wherein, The oil inlet pipeline is further provided with a power device for supplying oil to the energy storage device, the power device comprises an engine and a gear pump, the output end of the engine is connected with the gear pump, and the gear pump is connected between the hydraulic oil tank and the oil inlet pipeline.

5. An excavator hydraulic brake system as claimed in claim 4, wherein, The gear pump is connected in parallel with an overflow valve, and when the accumulator exceeds the set pressure of the overflow valve, the excessive oil overflows into the hydraulic oil tank.

6. A hydraulic braking system for a backhoe loader characterized by, The application relates to a single-circuit foot brake valve and a double-circuit foot brake valve. When the vehicle brakes, the pedals of the single-circuit foot brake valve and the double-circuit foot brake valve are pressed simultaneously, and the oil in the energy storage device reaches the rear drive axle through the oil outlet pipelines. When the vehicle turns, the pedals of the single-circuit foot brake valve and the double-circuit foot brake valve are pressed separately, and unilateral braking and turning are realized. The single-circuit foot brake valve and the double-circuit foot brake valve are all three-position three-way valves, which comprise an oil inlet, an oil outlet and an oil return, and the oil return is connected with the hydraulic oil tank.

7. An excavator hydraulic brake system as claimed in claim 6, wherein, The energy storage device comprises a check valve and an accumulator which are connected in series, and the output end of the check valve is communicated with the accumulator and connected with the oil inlets of the single-circuit foot brake valve and the double-circuit foot brake valve.

8. An excavator hydraulic brake system as claimed in claim 6, wherein, The oil inlet pipeline is further provided with a power device for supplying oil to the energy storage device, the power device comprises an engine and a gear pump, the output end of the engine is connected with the gear pump, and the gear pump is connected between the hydraulic oil tank and the oil inlet pipeline.

9. An excavator hydraulic brake system as claimed in claim 8, wherein, The gear pump is connected in parallel with an overflow valve, and when the accumulator exceeds the set pressure of the overflow valve, the excessive oil overflows into the hydraulic oil tank.

10. An excavator hydraulic brake system as claimed in claim 9, wherein, ​

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