WO2023284325A1

WO2023284325A1 - Hydraulic braking system and operating machine

Info

Publication number: WO2023284325A1
Application number: PCT/CN2022/082045
Authority: WO
Inventors: 张宁
Original assignee: 上海三一重机股份有限公司
Priority date: 2021-07-16
Filing date: 2022-03-21
Publication date: 2023-01-19
Also published as: CN215663380U

Abstract

A hydraulic braking system, comprising: a brake pump (100), an accumulator control valve set, an accumulator (200), a braking control valve, and an axle braking unit (300). An outlet of the brake pump (100) is connected to an inlet of the accumulator control valve set; an outlet of the accumulator control valve set is connected to the accumulator (200); the accumulator (200) is connected to the braking control valve; and the braking control valve is connected to the axle braking unit (300) so as to provide braking power hydraulic oil to the axle braking unit (300). The hydraulic braking system has a fast response speed, high braking sensitivity, and a short braking distance, and the system can adapt to workplaces such as narrow spaces or ramps, thereby improving the driving accuracy and the control safety. Meanwhile, the accumulator (200) supplies oil to the axle braking unit (300) when braking is needed without having to constantly immerse a friction plate and disc in axle oil, which reduces the requirements on the technical level of axle manufacturing and assembly and reduces costs. Further provided is an operating machine.

Description

Hydraulic brake system and working machinery

Cross References to Related Applications

This application claims priority to a Chinese patent application with application number 202121623030.X entitled "Hydraulic brake system and operating machinery" filed on July 16, 2021, which is incorporated herein by reference in its entirety.

technical field

The present application relates to the technical field of hydraulic systems, in particular to a hydraulic braking system and an operating machine.

Background technique

At present, there are usually two braking methods commonly used in working machines. One is an air top oil brake system with a dry brake bridge; the other is a hydraulic brake system with a wet brake bridge.

Among them, the braking method of air top oil brake system with dry brake bridge mainly uses air pressure to push the booster piston to generate hydraulic oil pressure, and the oil pressure acts on the clamp piston so that the friction plate is pressed against the disc. , the higher the air pressure, the greater the friction force of the friction plate against the disc, thereby generating braking force. Due to the relatively high compressibility of gas. After a person steps on the brake pedal, the brake pipeline will delay the establishment of air pressure, resulting in a delay in the brake response time of the whole machine. Therefore, the braking sensitivity of the air cap oil braking system is poor and the braking distance is large, which cannot be adapted to narrow spaces or working sites such as ramps, which has a great impact on driving accuracy and control safety.

The braking method of the hydraulic brake system with wet brake bridge is mainly to use the hydraulic oil pressure to push the friction plate to control the piston, so that the friction plate is pressed against the disc. The higher the hydraulic oil pressure, the greater the friction force of the friction plate against the disc. bigger. However, the hydraulic brake system with a wet brake axle needs to soak the friction plate and the disc in the axle oil. Therefore, the wet brake axle requires a high level of manufacturing and assembly technology, and the cost is also high.

Contents of the invention

The application provides a hydraulic braking system and a working machine, which are used to solve the problem of poor braking sensitivity and large braking distance of the air cap oil braking system used in the prior art, or the hydraulic braking system is not suitable for wet brakes. The manufacture and assembly of the dynamic axle has strict requirements and high cost. The hydraulic brake system is used with the brake method of the dry brake axle to improve the braking sensitivity of the brake system, shorten the braking distance, and reduce the technical requirements for manufacturing and assembly. , and the effect of reducing costs.

According to the first aspect of the present application, a hydraulic brake system is provided, including: a brake pump, an energy storage control valve group, an accumulator, a brake control valve and an axle brake unit.

Wherein, the outlet of the brake pump is connected with the inlet of the accumulator control valve group. The outlet of the accumulator control valve group is connected with the accumulator. The accumulator is connected to the brake control valve. The brake control valve is connected with the axle brake unit to provide braking power hydraulic oil for the axle brake unit.

According to a hydraulic braking system provided by the present application, the accumulator control valve group includes an accumulator control valve. The inlet of the accumulator control valve is connected with the brake pump. The outlet of the accumulator control valve is connected with the accumulator. The accumulator control valve is switchable between an on position and an off position.

Wherein, when the accumulator control valve is switched to the on position, the accumulator and the brake pump communicate with each other; when the accumulator control valve is switched to the cut-off position In the state, the accumulator and the brake pump are mutually blocked.

According to a hydraulic braking system provided by the present application, the accumulator control valve includes a two-position two-way reversing valve. The two-position two-way reversing valve includes a first working oil port, a second working oil port and a first control oil port. The first working oil port communicates with the brake pump, and the second working oil port communicates with the accumulator. The first control oil port communicates with the inlet of the accumulator.

According to a hydraulic braking system provided by the present application, the accumulator control valve group further includes an oil storage control valve. Both the brake pump and the accumulator control valve are connected to the oil storage control valve. The oil storage control valve can be switched between the oil supply level and the oil return level.

Wherein, when the oil storage control valve is switched to the oil supply level, the brake pump communicates with the accumulator control valve; when the oil storage control valve is switched to the oil return level , the brake pump communicates with the oil tank.

The oil storage control valve includes a first two-position three-way reversing valve. The first two-position three-way reversing valve includes a third working oil port, a fourth working oil port and a fifth working oil port.

Wherein, the third working oil port of the first two-position three-way reversing valve is connected with the outlet of the brake pump. The fourth working oil port of the first two-position three-way reversing valve communicates with the first working oil port of the two-two-way reversing valve. The fifth working oil port of the first two-position three-way reversing valve communicates with the oil tank.

According to a hydraulic braking system provided by the present application, the accumulator control valve group further includes a protection control valve. The protection control valve is connected with the oil storage control valve. The protection control valve can control the oil storage control valve to switch between the oil supply level and the oil return level.

According to a hydraulic braking system provided by the present application, the protection control valve includes a second two-position three-way reversing valve. The second two-position three-way reversing valve can be switched between a low-pressure conduction control position and a high-pressure cut-off control position.

The second two-position three-way reversing valve includes a sixth working oil port, a seventh working oil port, an eighth working oil port and a second control oil port. The first two-position three-way reversing valve also includes a third control oil port and a fourth control oil port.

Wherein, the sixth working oil port of the second two-two three-way reversing valve is connected with the fourth working oil port of the first two-two three-way reversing valve. The seventh working oil port of the second two-two three-way reversing valve is connected with the third control oil port of the first two-two three-way reversing valve. The eighth working oil port of the second two-position three-way reversing valve is connected with the oil tank. The second control oil port of the second two-position three-way reversing valve is connected with the first working oil port of the two-two-position two-way reversing valve. The fourth control oil port of the first two-position three-way reversing valve is connected with the outlet of the brake pump.

When the second two-position three-way reversing valve is switched to the low-pressure conduction control position, the resultant force of the control pressure of the third control oil port and the spring force is equal to the control pressure of the fourth control oil port , the first two-position three-way reversing valve is at the oil supply level, so as to deliver the hydraulic oil output from the brake pump to the accumulator. When the second two-position three-way reversing valve is switched to the high-pressure cut-off control position, the control pressure of the third control oil port is reduced to be equal to the internal pressure of the oil tank, so that the first two-position The three-way reversing valve is switched to the oil return level, so as to deliver the hydraulic oil output by the brake pump to the oil tank.

According to a hydraulic brake system provided by the present application, the brake control valve includes a pedal. The inlet of the pedal is connected with the accumulator. The outlet of the pedal is connected with the axle brake unit. The pedal can be switched between a walking position, a travel empty position and a braking position.

According to a hydraulic braking system provided by the present application, the axle braking unit includes at least one axle braking mechanism. Each axle braking mechanism is arranged in parallel. And each of the axle brake mechanisms is correspondingly provided with the accumulator, the accumulator control valve and the pedal.

According to a hydraulic brake system provided by the present application, an oil filter is arranged between the brake pump and the first two-position three-way reversing valve. A check valve is installed between the fourth working oil port of the first two-position three-way reversing valve and the first working oil port of the two-two-position two-way reversing valve.

According to a second aspect of the present application, there is provided a work machine, comprising the hydraulic braking system as described above.

In the hydraulic braking system provided by the present application, the outlet of the brake pump is connected to the inlet of the accumulator control valve group, and the outlet of the accumulator control valve group is connected to the accumulator, so The accumulator is connected to the brake control valve, and the brake control valve is connected to the axle brake unit to provide braking power hydraulic oil for the axle brake unit.

With this structural arrangement, the outlet of the brake pump is connected to the inlet of the accumulator. The brake pump is able to store hydraulic fluid for the accumulator. Both ends of the brake control valve are respectively connected with the accumulator and the axle brake unit. The brake control valve can control the accumulator to provide brake power hydraulic oil for the axle brake unit. Therefore, compared with the air-top oil braking system, the hydraulic braking system has fast response speed, high braking sensitivity and short braking distance, and can be adapted to work sites such as narrow spaces or ramps, greatly improving the Driving precision and handling safety. At the same time, the accumulator supplies oil to the axle brake unit only when braking is required, and there is no need to soak the friction plates and discs in the axle oil all the time. Therefore, compared with the wet brake axle brake system, the hydraulic brake system lowers the requirements on the manufacturing and assembly technology level of the axle, and at the same time reduces the cost accordingly.

Further, in the work machine provided by the present application, since the work machine includes the above-mentioned hydraulic braking system, it also has the above-mentioned various advantages.

Description of drawings

In order to more clearly illustrate the technical solutions in the embodiments of the present application or the prior art, the following will briefly introduce the drawings that need to be used in the description of the embodiments or the prior art. Obviously, the accompanying drawings in the following description are For some embodiments of the present application, those of ordinary skill in the art can also obtain other drawings based on these drawings without creative effort.

Fig. 1 is a schematic diagram of the system structure of the hydraulic braking system provided by the present application;

Reference signs:

100: brake pump; 200: accumulator;

300: axle brake unit; 301: axle brake mechanism;

400: Two-position two-way reversing valve; 401: The first working oil port;

402: The second working oil port; 403: The first control oil port;

404: On bit; 405: Cut off bit;

500: The first two two-way three-way reversing valve; 501: The third working oil port;

502: The fourth working oil port; 503: The fifth working oil port;

504: The third control oil port; 505: The fourth control oil port;

506: oil supply level; 507: oil return level;

600: The second two-position three-way reversing valve; 601: The sixth working oil port;

602: The seventh working oil port; 603: The eighth working oil port;

604: Second control oil port; 605: Low voltage conduction control bit;

606: High pressure cut-off control position; 700: Pedal;

701: travel position; 702: travel space;

703: braking position; 800: oil filter;

900: one-way valve.

detailed description

The implementation manner of the present application will be further described in detail below with reference to the drawings and embodiments. The following examples are used to illustrate the present application, but cannot be used to limit the scope of the present application.

In the description of the embodiments of the present application, it should be noted that the terms "center", "vertical", "transverse", "upper", "lower", "front", "rear", "left", "right" , "vertical", "horizontal", "top", "bottom", "inner", "outer" and other indicated orientations or positional relationships are based on the orientations or positional relationships shown in the drawings, and are only for the convenience of describing this The application embodiments and simplified descriptions do not indicate or imply that the devices or elements referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore should not be construed as limiting the embodiments of the application. In addition, the terms "first" and "second" are used for descriptive purposes only, and should not be understood as indicating or implying relative importance.

In the description of the embodiments of this application, it should be noted that unless otherwise specified and limited, the terms "connected" and "connected" should be understood in a broad sense, for example, it can be a fixed connection or a detachable connection, Or integrated connection; it can be mechanical connection or electrical connection; it can be direct connection or indirect connection through an intermediary. Those of ordinary skill in the art can understand the specific meanings of the above terms in the embodiments of the present application in specific situations.

In the embodiment of the present application, unless otherwise clearly specified and limited, the first feature may be in direct contact with the first feature or the first feature and the second feature may pass through the middle of the second feature. Media indirect contact. Moreover, "above", "above" and "above" the first feature on the second feature may mean that the first feature is directly above or obliquely above the second feature, or simply means that the level of the first feature is higher than that of the second feature. "Below", "beneath" and "beneath" the first feature may mean that the first feature is directly below or obliquely below the second feature, or simply means that the first feature is less horizontally than the second feature.

In the description of this specification, descriptions referring to the terms "one embodiment", "some embodiments", "example", "specific examples", or "some examples" mean that specific features described in connection with the embodiment or example , structures, materials or features are included in at least one embodiment or example of the embodiments of the present application. In this specification, the schematic representations of the above terms are not necessarily directed to the same embodiment or example. Furthermore, the described specific features, structures, materials or characteristics may be combined in any suitable manner in any one or more embodiments or examples. In addition, those skilled in the art can combine and combine the different embodiments or examples and the features of different embodiments or examples described in this specification to make the purposes and technical solutions of the embodiments of the present application and advantages are clearer. The technical solutions in the embodiments of the present application will be clearly and completely described below in conjunction with the accompanying drawings in the embodiments of the present application. Obviously, the described embodiments are part of the embodiments of the present application, not all of them. the embodiment. Based on the embodiments in this application, all other embodiments obtained by persons of ordinary skill in the art without creative efforts fall within the protection scope of this application.

A hydraulic braking system and a work machine provided in the embodiment of the present application will be described below with reference to FIG. 1 . It should be understood that the following descriptions are only exemplary embodiments of the present application, and do not constitute any special limitation to the present application.

The embodiment of the first aspect of the present application provides a hydraulic brake system, as shown in Figure 1, the hydraulic brake system includes: brake pump 100, energy storage control valve group, accumulator 200, brake control valve and the axle brake unit 300.

Wherein, the outlet of the brake pump 100 is connected with the inlet of the accumulator control valve group. The outlet of the accumulator control valve group is connected with the accumulator 200 . The accumulator 200 is connected to the brake control valve. The brake control valve is connected with the axle brake unit 300 to provide braking power hydraulic oil for the axle brake unit 300 .

With this structural arrangement, the outlet of the brake pump 100 is connected to the inlet of the accumulator 200 . The brake pump 100 can store hydraulic oil for the accumulator 200 . Both ends of the brake control valve are respectively connected to the accumulator 200 and the axle brake unit 300 . The brake control valve can control the accumulator 200 to provide brake power hydraulic oil for the axle brake unit 300 . Therefore, compared with the air-top oil braking system, the hydraulic braking system has fast response speed, high braking sensitivity and short braking distance, and can be adapted to work sites such as narrow spaces or ramps, greatly improving the Driving precision and handling safety. At the same time, the accumulator 200 supplies oil to the axle brake unit 300 when braking is required, without the need to soak the friction plates and discs in the axle oil all the time. Therefore, compared with the wet brake axle brake system, the hydraulic brake system lowers the requirements on the manufacturing and assembly technology level of the axle, and at the same time reduces the cost accordingly.

In one embodiment of the present application, the accumulator control valve group includes an accumulator control valve. The inlet of the accumulator control valve is connected to the brake pump 100 . The outlet of the accumulator control valve is connected with the accumulator 200 . The accumulator control valve can be switched between an on position 404 and an off position 405 .

Wherein, when the accumulator control valve is switched to the on position 404, the accumulator 200 and the brake pump 100 are connected to each other; .

For example, in one embodiment of the present application, the accumulator control valve includes a two-position two-way reversing valve 400 . The two-position two-way reversing valve 400 includes a first working oil port 401 , a second working oil port 402 and a first control oil port 403 . The first working oil port 401 communicates with the brake pump 100 . The second working oil port 402 communicates with the accumulator 200 . The first control oil port 403 communicates with the inlet of the accumulator 200 .

As shown in FIG. 1 , there are two accumulators 200 in the figure, and each accumulator 200 is connected with an accumulator control valve. The respective corresponding accumulator control valves can control the brake pump 100 to store oil for the accumulator 200 .

Specifically, when the oil in the accumulator 200 is in an unsaturated state, the pressure at the inlet of the accumulator 200 is relatively low, the two-position two-way reversing valve 400 is at the on position 404, and the first working oil port 401 It is connected with the second working oil port 402 , so that the outlet of the brake pump 100 is connected with the inlet of the accumulator 200 , and the oil output from the brake pump 100 can continuously enter and store in the accumulator 200 . When the accumulator 200 is filled with oil, the inlet pressure of the accumulator 200 is high, the two-position two-way reversing valve 400 is switched to the cut-off position 405, and the first working oil port 401 and the second working oil port 402 are mutually blocked , so that the accumulator 200 stops storing hydraulic oil.

For another example, the upper limit of the fluid filling pressure of the accumulator 200 may be set to be 15-19 MPa, and the lower limit of the fluid filling pressure may be set to be 11-13 MPa. On the premise of ensuring normal braking pressure, the best energy saving effect is achieved.

Assume that the upper limit of the filling pressure of the accumulator 200 is set to 16MPa, when the two-position two-way reversing valve 400 detects that the pressure of the accumulator 200 is higher than 16MPa, it switches to the cut-off position 405, and the accumulator 200 stops stock solution. Set the lower limit of the filling pressure of the accumulator 200 to 11MPa. When the two-position two-way reversing valve 400 detects that the pressure of the accumulator 200 is lower than 11MPa, it switches to the ON position 404, and the accumulator 200 starts to store liquid.

For another example, the liquid storage rate of the accumulator 200 may be 10.2-20 L/min. Guaranteed to meet the demand of braking flow in the case of continuous braking.

The accumulator 200 can use an accumulator with a capacity of 1.4L. After the engine is turned off, the effective braking times are 3-5 times. During normal use, frequent liquid filling is avoided to ensure the life of the components.

In one embodiment of the present application, the accumulator control valve group further includes an oil storage control valve. Both the brake pump 100 and the accumulator control valve are connected with the oil storage control valve. The oil storage control valve can switch between the oil supply level 506 and the oil return level 507 .

Wherein, when the oil storage control valve switches to the oil supply level 506, the brake pump 100 communicates with the accumulator control valve; when the oil storage control valve switches to the oil return level 507, the brake pump 100 communicates with the fuel tank.

For example, in one embodiment of the present application, the oil storage control valve includes a first two-position three-way reversing valve 500 . The first two-position three-way reversing valve 500 includes a third working oil port 501 , a fourth working oil port 502 and a fifth working oil port 503 .

Wherein, the third working oil port 501 of the first two-position three-way reversing valve 500 is connected with the outlet of the brake pump 100 . The fourth working oil port 502 of the first two-two three-way reversing valve 500 communicates with the first working oil port 401 of the two-two-way reversing valve 400 . The fifth working oil port 503 of the first two-position three-way reversing valve 500 communicates with the oil tank.

Further, in one embodiment of the present application, the accumulator control valve group further includes a protection control valve. The protection control valve is connected with the oil storage control valve. The protection control valve can control the oil storage control valve to switch between the oil supply level 506 and the oil return level 507 .

For example, in one embodiment of the present application, the protection control valve includes a second two-position three-way reversing valve 600 . The second two-position three-way reversing valve 600 can be switched between a low-pressure conduction control position 605 and a high-pressure cut-off control position 606 .

The second two-position three-way reversing valve 600 includes a sixth working oil port 601 , a seventh working oil port 602 , an eighth working oil port 603 and a second control oil port 604 . The first two-position three-way reversing valve 500 also includes a third control oil port 504 and a fourth control oil port 505 .

Wherein, the sixth working oil port 601 of the second two-two three-way reversing valve 600 is connected with the fourth working oil port 502 of the first two-two three-way reversing valve 500 . The seventh working oil port 602 of the second two-two three-way reversing valve 600 is connected with the third control oil port 504 of the first two-two three-way reversing valve 500 . The eighth working oil port 603 of the second two-position three-way reversing valve 600 is connected with the oil tank. The second control oil port 604 of the second two-position three-way reversing valve 600 is connected with the first working oil port 401 of the two-position two-way reversing valve 400 . The fourth control oil port 505 of the first two-position three-way reversing valve 500 is connected with the outlet of the brake pump 100 .

When the second two-position three-way reversing valve 600 switches to the low-pressure conduction control position 605, the resultant force of the control pressure of the third control oil port 504 and the spring force is equal to the control pressure of the fourth control oil port 505, and the first two-position The three-way reversing valve 500 is at the oil supply level 506, so as to deliver the hydraulic oil output by the brake pump 100 to the accumulator 200;

When the second two-position three-way reversing valve 600 is switched to the high-pressure cut-off control position 606, the control pressure of the third control oil port 504 is reduced to be equal to the internal pressure of the oil tank, so that the first two-two three-way reversing valve 500 is switched to Return the oil level 507 to deliver the hydraulic oil output by the brake pump 100 to the oil tank.

Specifically, as shown in Figure 1, the accumulator control valve group also includes an oil storage control valve and a protection control valve. For example, the oil storage control valve includes a first two-position three-way reversing valve 500 ; the protection control valve includes a second two-position three-way reversing valve 600 .

Wherein, the second two-position three-way reversing valve 600 can switch between the low-pressure conduction control position 605 and the high-pressure cut-off control position 606 according to the inlet pressure of the accumulator 200 . The second two-position three-way reversing valve 600 can control the first two-position three-way reversing valve 500 to switch between the oil supply level 506 and the oil return level 507 .

Specifically, Fig. 1 shows that the accumulator 200 is in the working state of oil storage. When the accumulator 200 is in the continuous oil storage state, the inlet pressure of the accumulator 200 is relatively small, and the second two-position three-way commutation The pressure of the second control oil port 604 of the valve 600 is relatively small, so that the second two-position three-way reversing valve 600 is at the low-pressure conduction control position 605 . At this time, the sixth working oil port 601 communicates with the seventh working oil port 602 .

The fourth working oil port 502 of the first two-two three-way reversing valve 500 communicates with the sixth working oil port 601 of the second two-two three-way reversing valve 600, and the seventh working oil port 601 of the second two-two three-way reversing valve 600 The working oil port 602 communicates with the third control oil port 504 of the first two-two three-way reversing valve 500 , and the fourth control oil port 505 of the first two-two three-way reversing valve 500 communicates with the outlet of the brake pump 100 .

At this time, the control pressures of the third control oil port 504 and the fourth control oil port 505 of the first two-position three-way reversing valve 500 are equal. A spring is also installed inside the first two-position three-way reversing valve 500 . Under the action of the spring force, the first two-position three-way reversing valve 500 is kept at the oil supply level 506 , so that the hydraulic oil output by the brake pump 100 can be delivered to the accumulator 200 .

When the accumulator 200 is in a saturated state, the two-position two-way reversing valve 400 connected thereto is first switched to the cut-off position 405 . At this moment, the pressure of the second control oil port 604 of the second two-position three-way reversing valve 600 increases, so that the second two-two three-way reversing valve 600 switches to the high-pressure cut-off control position 606 . The seventh working oil port 602 and the eighth working oil port 603 of the second two-position three-way reversing valve 600 communicate with each other. Since the eighth working oil port 603 communicates with the oil tank, the seventh working oil port 602 communicates with the third control oil port 504 of the first two-position three-way reversing valve 500. At this time, the control pressure of the third control oil port 504 is the same as The pressure inside the tank is equal and close to zero. The pressure of the fourth control oil port 505 is equal to the outlet pressure of the brake pump 100 . Under the action of the pressure difference between the spring force and the control pressure of the fourth control oil port 505, the first two-position three-way reversing valve 500 is switched to the oil return level 507, so that the hydraulic oil output by the brake pump 100 flows back into the oil tank. The hydraulic system plays a protective role.

In one embodiment of the present application, the brake control valve includes a pedal 700 . The inlet of the pedal 700 is connected to the accumulator 200 . An outlet of the pedal 700 is connected to the axle brake unit 300 . The pedal 700 can be switched between a walking position 701 , a travel empty position 702 and a braking position 703 .

As shown in FIG. 1 , the driver can realize the braking action by stepping on the pedal 700 . Simultaneously, the pedal 700 can be switched between the walking position 701 , the travel space 702 and the braking position 703 . By setting the travel gap 702, the working machine can be smoothly transitioned between the walking state and the braking state, effectively improving driving safety and stability.

In one embodiment of the present application, the axle brake unit 300 includes at least one axle brake mechanism 301 . The axle braking mechanisms 301 are arranged in parallel. And each axle braking mechanism 301 is provided with an accumulator 200 , an accumulator control valve and a pedal 700 correspondingly. It can also be said that the hydraulic braking system can be a single-circuit hydraulic system or a double-circuit hydraulic system. Each hydraulic circuit correspondingly controls an axle braking mechanism 301 .

For example, as shown in Figure 1, it is a dual-circuit hydraulic braking system. That is, in this embodiment, the axle brake unit 300 includes two axle brake mechanisms 301 . That is to say, this embodiment is suitable for double-axle braking. The axle braking mechanisms 301 are arranged in parallel, and each axle braking mechanism 301 is correspondingly equipped with an accumulator 200 , an accumulator control valve and a pedal 700 .

In one embodiment of the present application, an oil filter 800 is disposed between the brake pump 100 and the first two-position three-way reversing valve 500 . A check valve 900 is installed between the fourth working oil port 502 of the first two-position three-way reversing valve 500 and the first working oil port 401 of the two-position two-way reversing valve 400 .

According to the embodiments described above, by disposing the oil filter 800 at the outlet of the brake pump 100 , impurities can be effectively prevented from entering the hydraulic braking system, thereby effectively protecting the hydraulic braking system. At the same time, installing a one-way valve 900 at the outlet of the oil storage control valve can effectively prevent the oil from flowing back.

An embodiment of the second aspect of the present application provides a working machine, the working machine includes the hydraulic braking system as described above.

For example, the aforementioned work machines include loaders.

It should be understood here that the above embodiment is only an exemplary embodiment of the present application, and does not constitute any limitation to the present application. That is to say, the aforementioned work machines include but are not limited to loaders.

Further, since the working machine includes the hydraulic braking system as described above, it also has the advantages as described above.

Finally, it should be noted that: the above embodiments are only used to illustrate the technical solutions of the present application, rather than limiting them; although the present application has been described in detail with reference to the foregoing embodiments, those of ordinary skill in the art should understand that: it can still Modifications are made to the technical solutions described in the foregoing embodiments, or equivalent replacements are made to some of the technical features; and these modifications or replacements do not make the essence of the corresponding technical solutions deviate from the spirit and scope of the technical solutions of the various embodiments of the present application.

Claims

A hydraulic braking system, comprising: a brake pump, an energy storage control valve group, an accumulator, a brake control valve and an axle brake unit,

Wherein, the outlet of the brake pump is connected to the inlet of the accumulator control valve group, the outlet of the accumulator control valve group is connected to the accumulator, and the accumulator is connected to the brake The control valve is connected, and the brake control valve is connected with the axle brake unit to provide braking power hydraulic oil for the axle brake unit.
The hydraulic braking system according to claim 1, wherein the accumulator control valve group comprises an accumulator control valve, the inlet of the accumulator control valve is connected to the brake pump, and the The outlet of the accumulator control valve is connected to the accumulator, and the accumulator control valve can be switched between the on position and the cut off position,

Wherein, when the accumulator control valve is switched to the on position, the accumulator and the brake pump communicate with each other; when the accumulator control valve is switched to the cut-off position In the state, the accumulator and the brake pump are mutually blocked.
The hydraulic braking system according to claim 2, wherein the accumulator control valve includes a two-position two-way reversing valve, and the two-position two-way reversing valve includes a first working oil port, a second Working oil port and first control oil port, the first working oil port communicates with the brake pump, the second working oil port communicates with the accumulator, the first control oil port communicates with the The inlet of the accumulator is connected.
The hydraulic braking system according to claim 3, wherein the accumulator control valve group further includes an oil storage control valve, and both the brake pump and the accumulator control valve are connected to the oil storage The control valve is connected, and the oil storage control valve can switch between the oil supply level and the oil return level,

Wherein, when the oil storage control valve is switched to the oil supply level, the brake pump communicates with the accumulator control valve; when the oil storage control valve is switched to the oil return level , the brake pump communicates with the fuel tank;

The oil storage control valve includes a first two-position three-way reversing valve, and the first two-position three-way reversing valve includes a third working oil port, a fourth working oil port and a fifth working oil port,

Wherein, the third working oil port of the first two-two three-way reversing valve is connected to the outlet of the brake pump, and the fourth working oil port of the first two-two three-way reversing valve is connected to the outlet of the two The first working oil port of the two-position two-way reversing valve is connected, and the fifth working oil port of the first two-two three-way reversing valve is connected with the oil tank.
The hydraulic braking system according to claim 4, wherein the accumulator control valve group further includes a protection control valve, the protection control valve is connected with the oil storage control valve, and the protection control valve can The oil storage control valve is controlled to switch between the oil supply level and the oil return level.
The hydraulic braking system according to claim 5, wherein the protection control valve includes a second two-position three-way reversing valve, and the second two-position three-way reversing valve can be in the low-pressure conduction control position. and high voltage cutoff control bits to switch between,

The second two-position three-way reversing valve includes a sixth working oil port, a seventh working oil port, an eighth working oil port and a second control oil port, and the first two-two three-way reversing valve further includes a first The third control port and the fourth control port,

Wherein, the sixth working oil port of the second two-position three-way reversing valve is connected to the fourth working oil port of the first two-two-three-way reversing valve, and the second two-two three-way reversing valve The seventh working oil port of the first two-position three-way reversing valve is connected with the third control oil port, and the eighth working oil port of the second two-two-three-way reversing valve is connected with the oil tank, so The second control oil port of the second two-two three-way reversing valve is connected to the first working oil port of the two-two-two-way reversing valve, and the fourth control oil port of the first two-two three-way reversing valve The port is connected with the outlet of the brake pump,

When the second two-position three-way reversing valve is switched to the low-pressure conduction control position, the resultant force of the control pressure of the third control oil port and the spring force is equal to the control pressure of the fourth control oil port , the first two-position three-way reversing valve is at the oil supply level to deliver the hydraulic oil output by the brake pump to the accumulator; When the control position is cut off, the control pressure of the third control oil port is reduced to be equal to the internal pressure of the oil tank, so that the first two-two three-way reversing valve is switched to the oil return level, so that the brake The hydraulic oil output by the pump is delivered to the oil tank.
The hydraulic braking system according to claim 1, wherein the brake control valve includes a pedal, the inlet of the pedal is connected to the accumulator, and the outlet of the pedal is connected to the axle brake. The unit is connected, and the pedal can be switched between the walking position, the travel space and the braking position.
The hydraulic braking system according to claim 7, wherein the axle brake unit includes at least one axle brake mechanism, each of the axle brake mechanisms is arranged in parallel, and each of the axle brake mechanisms The actuating mechanism is correspondingly provided with the accumulator, the accumulator control valve and the pedal.
The hydraulic braking system according to claim 4, wherein an oil filter is arranged between the brake pump and the first two-position three-way reversing valve, and the first two-position three-way A check valve is installed between the fourth working oil port of the reversing valve and the first working oil port of the two-position two-way reversing valve.
A work machine, comprising the hydraulic braking system according to any one of claims 1-9.