Loader brake hydraulic system

Abstract

The utility model relates to the technical field of engineering machinery, and provides a loader brake hydraulic system which comprises an oil pump, the oil outlet end of the oil pump is connected with the P end of a prefill valve, and the A end of the prefill valve is connected with an energy accumulator through a first branch; the end A of the prefill valve is connected with a foot brake valve through a second branch, the end A of the foot brake valve is connected with a service brake end, and the end SW of the prefill valve is connected with a service brake pressure sensor; the A end of the prefill valve is connected with a parking braking electromagnetic valve and a differential lock electromagnetic valve through a third branch, the SW end of the parking braking electromagnetic valve is connected with a parking braking end, the SW end of the differential lock electromagnetic valve is connected with a front axle and a rear axle of a vehicle body, the B end of the parking braking electromagnetic valve is connected with a parking braking pressure sensor, and the B end of the differential lock electromagnetic valve is connected with a differential lock pressure sensor. Hydraulic control and mechanical release are independently controlled and do not interfere with each other, and when a muddy or slippery road surface is met, the wheels are prevented from slipping.

Description

TECHNICAL FIELD

[0001] The utility model relates to engineering machinery technical field, concretely relates to a loader braking hydraulic system. BACKGROUND

[0002] The loader is important mechanical equipment in engineering machinery construction, and is mainly used for the shovel, loading, transportation and other operations of loose materials; the working condition of the loader is mainly shovel excavation operation and loading operation, and the working device needs to be collected, lifted, unloaded and lowered, and the whole machine needs to be frequently braked;

[0003] And the loader is often used in muddy sections, and when one side of the wheel loses the grip in the muddy or icy road section, it is equivalent to no resistance, and the other side of the wheel is equivalent to fixed, the rotation of the planetary gear transmits all the power to the side wheel that loses the grip, and the car can only stay in place, at this time, the differential plays a role of a reverse action, the differential lock plays a role of a forced intervention, and the left and right shafts become rigidly connected, and the side with resistance has power, so that the vehicle can drive out of the mud and continue to move forward.

[0004] And the existing loader brake axle currently adopts the mechanical control differential lock, and the rotation speed of all the wheels can be detected through the sensor in the muddy and slippery road condition, and then the differential is carried out, and the reaction is slightly slow, the mechanical control differential lock must act when the speed difference appears, and the wheel has lost the grip when the speed difference appears, so that the misjudgment risk exists. UTILITY MODEL CONTENTS

[0005] The utility model aims at providing a loader braking hydraulic system, which can solve the existing problems.

[0006] In order to achieve the above object, the utility model provides a loader braking hydraulic system, which comprises an oil pump, the oil pump is connected with the liquid filling valve P end, the liquid filling valve A end is connected with the energy accumulator through the first branch;

[0007] The liquid filling valve A end is connected with the foot brake valve through the second branch, the foot brake valve A end is connected with the service brake end, and the liquid filling valve SW end is connected with the service brake pressure sensor;

[0008] The liquid filling valve A end is connected with the parking brake electromagnetic valve and the differential lock electromagnetic valve through the third branch, the parking brake electromagnetic valve SW end is connected with the parking brake end, the differential lock electromagnetic valve SW end is connected with the vehicle body rear axle, the parking brake electromagnetic valve B end is connected with the parking brake pressure sensor, and the differential lock electromagnetic valve B end is connected with the differential lock pressure sensor.

[0009] Further, the liquid filling valve comprises a pressure reducing valve, a first two-position three-way pilot pressurizing valve, a filter, a throttle valve, a check valve and a second two-position three-way pilot pressurizing valve, the liquid filling valve is connected with the pressure reducing valve at the P end, the two-position three-way pilot pressurizing valve is connected in parallel above the pressure reducing valve, the two-position three-way pilot pressurizing valve is sequentially connected with the filter, the throttle valve and the check valve at the oil outlet end.

[0010] Further, the first two-position three-way pilot pressurizing valve is connected with the hydraulic oil tank at the T end, and the second two-position three-way pilot pressurizing valve is connected with the hydraulic oil tank at the O end.

[0011] Further, the foot brake valve is a three-position three-way valve.

[0012] Further, the parking brake solenoid valve and the differential lock solenoid valve each comprise a two-position three-way electromagnetic pilot valve and a check valve.

[0013] Further, one end of the two-position three-way electromagnetic pilot valve is connected with the parking brake pressure sensor or the differential lock pressure sensor through the B branch, and the other end of the two-position three-way electromagnetic pilot valve is connected with the parking brake end or the rear axle of the vehicle body through the SW branch.

[0014] Further, the other end of the two-position three-way electromagnetic pilot valve is connected with the liquid filling valve at the A end through the check valve and the electromagnetic pilot valve at the P end.

[0015] Further, the oil pump is connected with the liquid filling valve at the P end through the filter, and the parking brake solenoid valve at the B end, the differential lock solenoid valve at the B end and the foot brake valve at the T end are simultaneously connected with the oil tank.

[0016] Further, the check valve is connected with the second two-position three-way pilot pressurizing valve.

[0017] The above one or more technical solutions have the following beneficial effects:

[0018] By connecting the differential lock solenoid valve and the foot brake valve in parallel in the parking brake solenoid valve oil circuit, when encountering muddy or wet road surfaces, the differential lock solenoid valve or the foot brake valve can be actuated through the electric control handle or switch before entering the wet road surface, so as to prevent the wheels from slipping, the differential lock solenoid valve or the foot brake valve is connected with the differential lock mechanical brake structure of the vehicle body through the outlet A, so as to lock the front and rear axle differentials, so that the left and right wheels have the same rotating speed, and the brake is manually operated through the electric control handle or switch, so as to realize rapid control and smoothly pass through the corresponding road conditions. BRIEF DESCRIPTION OF DRAWINGS

[0019] The drawings constituting a part of the specification of the present application are used to provide further understanding of the present application, the illustrative embodiments of the present application and the description thereof are used to explain the present application, and do not constitute a limitation on the present application.

[0020] Figure 1 The structure of the present application is a schematic diagram.

[0021] Figure 2 The mechanical brake structure of the utility model is a structure diagram.

[0022] In the figure, 1 engine; 2 oil pump; 3 filter;

[0023] 4 accumulator;

[0024] 5 liquid filling valve; 51 pressure reducing valve; 52 first two-position three-way pilot pressurizing valve; 53 filter; 54 throttle valve;

[0025] 55 check valve; 56 second two-position three-way pilot pressurizing valve;

[0026] 6 foot brake valve; 61 service brake pressure sensor;

[0027] 7 parking brake solenoid valve; 71 parking brake pressure sensor;

[0028] 8 differential lock solenoid valve; 81 differential lock pressure sensor;

[0029] 9 hydraulic oil tank; 10 service brake end; 11 vehicle body front and rear axle; 12 parking brake end. DETAILED DESCRIPTION

[0030] The specific implementation of the embodiment will be described below in combination with the drawings.

[0031] Embodiment one

[0032] Referring to Figure 1 A loader brake hydraulic system, comprising an oil pump 2, the oil outlet end of the oil pump 2 is connected with the P end of a liquid filling valve 5, the A end of the liquid filling valve 5 is connected with an accumulator 4 through a first branch, when the engine 1 cannot normally start due to leakage or failure, or when the pressure of the accumulator 4 is relatively low under extreme conditions, etc., at this time, the whole vehicle is in a parking brake state, when the vehicle needs to be towed, the parking brake can be released through a wrench;

[0033] The A end of the liquid filling valve 5 is connected with a foot brake valve 6 through a second branch, the A end of the foot brake valve 6 is connected with a service brake end 10, and the SW end of the liquid filling valve 5 is connected with a service brake pressure sensor 61, when the pressure of the service brake pressure sensor 61 is lower than a certain set value, the system will alarm to indicate a fault or the vehicle needs to be started to fill liquid;

[0034] The A end of the liquid filling valve 5 is connected with a parking brake solenoid valve 7 and a differential lock solenoid valve 8 through a third branch, the SW end of the parking brake solenoid valve 7 is connected with a parking brake end 12, the SW end of the differential lock solenoid valve 8 is connected with a vehicle body rear axle, the B end of the parking brake solenoid valve 7 is connected with a parking brake pressure sensor 71, and the B end of the differential lock solenoid valve 8 is connected with a differential lock pressure sensor 81, when the pressure of the parking brake / differential lock pressure sensor 81 is lower than a certain set value, the system will alarm to indicate a fault or the vehicle needs to be started to fill liquid.

[0035] The liquid filling valve 5 comprises a pressure reducing valve 51, a first two-position three-way pilot pressurizing valve 52, a filter 3, a throttle valve, a one-way valve 55 and a second two-position three-way pilot pressurizing valve 56, the liquid filling valve 5P end is connected with the pressure reducing valve 51, the pressure reducing valve 51 is connected with the two-position three-way pilot pressurizing valves in parallel, the two-position three-way pilot pressurizing valve oil outlet is connected with the filter 3, the throttle valve and the one-way valve 55 in sequence, the one-way valve 55 is connected with the second two-position three-way pilot pressurizing valve 56, and the right position is communicated in the initial state.

[0036] The first two-position three-way pilot pressurizing valve 52 is connected with the hydraulic oil tank 9 through the T end, and the second two-position three-way pilot pressurizing valve 56 is connected with the hydraulic oil tank 9 through the O end.

[0037] The foot brake valve 6 is a two-position three-way valve, realizes rapid control, can adopt an electromagnetic electromagnetic valve, and is within the protection scope of the utility model, the right position is communicated in the initial state, and the left position is communicated after the two-position three-way valve is powered on.

[0038] The parking brake electromagnetic valve 7 and the differential lock electromagnetic valve 8 both comprise a two-position three-way electromagnetic pilot valve and a one-way valve 55, one end of the two-position three-way electromagnetic pilot valve is connected with the parking brake pressure sensor 71 or the differential lock pressure sensor 81 through a B end branch, and one end of the two-position three-way electromagnetic pilot valve is connected with the parking brake end 12 or the vehicle body front and rear axle 11 through a SW end branch.

[0039] The other end of the two-position three-way electromagnetic pilot valve is connected with the liquid filling valve 5A end through the one-way valve 55 and an electromagnetic pilot valve P end.

[0040] The oil pump 2 is connected with the liquid filling valve 5P end through the filter 3, the parking brake electromagnetic valve 7B end, the differential lock electromagnetic valve 8B end and the foot brake valve 6T end are simultaneously connected with the oil tank, oil liquid backflow is carried out, and the parking brake electromagnetic valve 7, the differential lock electromagnetic valve 8 and the foot brake valve 6 simultaneously backflow into the oil tank through the same oil circuit.

[0041] The oil pump 2 is connected with the engine 1, when the engine 1 is started, the oil pump 2 is driven to work, hydraulic oil is filtered through the filter 3 and then charges the accumulator 4 through the liquid filling valve 5.

[0042] The one-way valve is connected with the second two-position three-way pilot pressurizing valve.

[0043] The brake principle is as follows:

[0044] The engine 1 drives the oil pump 2 to work, and the hydraulic oil is filtered through the filter 3 and then charges the accumulator 4 through the charging valve 5; after charging, the engine 1 is turned off and only powered on, at this time the accumulator 4 stores hydraulic oil, and the operation of the electric control handle or switch realizes the action of the parking brake solenoid valve 7, realizing the parking in the off state; when the vehicle is running, when the sensor pressure connected to the charging valve 5 is lower than the set value, the charging valve 5 will automatically charge the accumulator 4; at this time, the action of the foot brake valve 6 realizes the driving brake of the front and rear axles; when the vehicle stops, the action of the parking brake solenoid valve 7 can be realized through the electric control handle or switch, that is, the parking brake of the vehicle can be realized; when encountering muddy or slippery road surface, the action of the differential lock solenoid valve 8 is realized by operating the electric control handle or switch, the front and rear axle differentials are locked, and the left and right wheel rotation speeds are the same, with reference to Figure 2 The mechanical brake structure is connected to the hydraulic system, and the mechanical brake structure is the existing differential, and one side of the differential is connected to the foot brake valve A port or the parking brake or the differential lock solenoid valve SW.

[0045] When the driving brake pressure sensor 61, the parking brake pressure sensor 71, and the differential lock pressure sensor 81 are lower than a certain set value, the system will alarm and prompt the fault or need to be charged by the vehicle.

[0046] Although the specific embodiments of the utility model are described above with reference to the drawings, it is not a limitation on the protection scope of the utility model, and those skilled in the art should understand that various modifications or deformations made by the skilled in the art on the basis of the technical scheme of the utility model without creative labor are still within the protection scope of the utility model.

Claims

1. A loader brake hydraulic system characterized by, The oil pump is connected with the liquid filling valve P end, the liquid filling valve A end is connected with the accumulator through the first branch; The liquid filling valve A end is connected with the foot brake valve through the second branch, the foot brake valve A end is connected with the service brake end, and the liquid filling valve SW end is connected with the service brake pressure sensor. The liquid filling valve A end is connected with the parking brake electromagnetic valve and the differential lock electromagnetic valve through the third branch, the parking brake electromagnetic valve SW end is connected with the parking brake end, the differential lock electromagnetic valve SW end is connected with the front and rear axle of the vehicle body, the parking brake electromagnetic valve B end is connected with the parking brake pressure sensor, and the differential lock electromagnetic valve B end is connected with the differential lock pressure sensor.

2. A loader brake hydraulic system as claimed in claim 1, wherein, The liquid filling valve comprises a pressure reducing valve, a first two-position three-way pilot pressure valve, a filter, a throttle valve, a check valve and a second two-position three-way pilot pressure valve, the liquid filling valve P end is connected with the pressure reducing valve, the pressure reducing valve is connected with the two-position three-way pilot pressure valve in parallel, the two-position three-way pilot pressure valve oil outlet is connected with the filter, the throttle valve and the check valve in sequence, and the check valve is connected with the second two-position three-way pilot pressure valve.

3. A loader brake hydraulic system as claimed in claim 2, wherein, The first two-position three-way pilot pressure valve is connected with the hydraulic oil tank through the T end, and the second two-position three-way pilot pressure valve is connected with the hydraulic oil tank through the O end.

4. The hydraulic loader brake system of claim 1 wherein, The foot brake valve is a three-position three-way valve.

5. The hydraulic loader brake system of claim 1 wherein, The parking brake electromagnetic valve and the differential lock electromagnetic valve each comprise a two-position three-way electromagnetic pilot valve and a check valve.

6. A loader brake hydraulic system as claimed in claim 5, wherein, One end of the two-position three-way electromagnetic pilot valve is connected with the parking brake pressure sensor or the differential lock pressure sensor through the B end branch, and one end of the two-position three-way electromagnetic pilot valve is connected with the parking brake end or the rear axle of the vehicle body through the SW end branch.

7. A loader brake hydraulic system as claimed in claim 6, wherein, The other end of the two-position three-way electromagnetic pilot valve is connected with the liquid filling valve A end through the check valve and the electromagnetic pilot valve P end.

8. The hydraulic loader brake system of claim 1 wherein, The oil pump is connected with the liquid filling valve P end through the filter, the parking brake electromagnetic valve B end, the differential lock electromagnetic valve B end and the foot brake valve T end are simultaneously connected with the oil tank.

9. The hydraulic loader brake system of claim 1 wherein, The oil pump is connected with the engine.

10. The hydraulic loader brake system of claim 1 wherein, The check valve is connected with the second two-position three-way pilot pressure valve. The oil pump is connected with the engine. The check valve is connected with the second two-position three-way pilot pressure valve.

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