WO2017071596A1

WO2017071596A1 - Hydraulic system of two-way driving shuttle vehicle

Info

Publication number: WO2017071596A1
Application number: PCT/CN2016/103437
Authority: WO
Inventors: 何春栋; 杨东升; 张晓东; 何利萍; 余晓军; 王立新
Original assignee: 中国国际海运集装箱(集团)股份有限公司; 民航协发机场设备有限公司; 廊坊中集空港设备有限公司; 深圳中集天达空港设备有限公司
Priority date: 2015-10-28
Filing date: 2016-10-26
Publication date: 2017-05-04
Also published as: DE112016002811T5; CN106640854A

Abstract

A hydraulic system of a two-way driving shuttle vehicle. The two-way driving shuttle vehicle comprises two axles (10) arranged at either the front or rear side of the vehicle, two sets of axle-locking mechanisms capable of locking straight respectively the two axles (10), and two sets of power steering mechanisms capable of power steering respectively the two axles (10). The hydraulic system of the two-way driving shuttle vehicle comprises: a hydraulic fluid tank (1) comprising: an axle-locking fluid tank (11) and a power steering fluid tank (12) arranged within the axle-locking fluid tank (11); an axle-locking circuit in communication between the axle-locking fluid tank (11) and the two sets of axle-locking mechanisms; and a power steering circuit in communication between the power steering fluid tank (12) and the two sets of power steering mechanisms. The hydraulic system of the two-way driving shuttle vehicle, by combining a fluid tank of a hydraulic axle-locking system and a fluid tank of a hydraulic power steering system of the two-way driving shuttle vehicle into one shared hydraulic fluid tank, simplifies the hydraulic system of the two-way driving shuttle vehicle, and solves the problem of overheating of the hydraulic fluid of the hydraulic power steering system.

Description

Two-way driving van hydraulic system

Technical field

The invention relates to the technical field of a shuttle bus, and in particular to a hydraulic system of a two-way traveling and swinging vehicle.

Background technique

The airport shuttle bus is used to pick up and drop off passengers and passengers between the terminal and the remote aircraft. It is suitable for the landings and other places of the civil aviation airports. For smaller airports, the two-way shuttle is more suitable for its smaller driving space because it has two driving heads. When the driver needs to turn around during driving, he only needs to drive on the other driving head. The emergence of the two-way shuttle bus effectively solves the problem that the airport shuttle bus has a large turning radius and is difficult to turn around.

Among the existing two-way traveling shuttles, one uses a full hydraulic drive, and the hydraulic system is mainly used to realize the functions of driving the vehicle to walk, turn and lock the bridge. The hydraulic system is used for power steering and hydraulic lock when the vehicle is running (hydraulic pressure keeps the wheel straight as defined as a hydraulic lock bridge). The lock function of the hydraulic system is mainly freely steered by the axle of the driver's head, and the axle of the other driver's head is locked by the hydraulic system and the tires on both sides are kept under the certain hydraulic pressure and the axle. The axis is vertical. The full load quality of the airport shuttle bus is generally around 20t, and the driving speed is generally between 30km/h and 50km/h. The hydraulic system drives the vehicle to generate a lot of heat during the walking process, which causes the temperature of the system to rise and easily seals. Aging, oil leakage, environmental pollution and system inefficiency.

Among the existing two-way walking and swinging vehicles, the other uses walking and steering depending on the mechanical driving form, and the hydraulic system is used for the technical measures of assisting steering and locking the bridge. The hydraulic system power steering mainly uses the hydraulic power steering machine to increase the steering drive force, making the manpower steering easier. The locking function of the hydraulic system is mainly freely steered by the axle of the driver's driving head. The axle of the other driving head is locked by the hydraulic system and the tires on both sides are kept at a certain hydraulic pressure and the axle of the axle. vertical. The hydraulic system mainly has the following problems: the hydraulic power steering system uses a vehicle-specific steering oil can, which has serious oil heating during use, leading to sealing aging, oil leakage and the like, affecting the safety and reliability of the steering system.

Therefore, a hydraulic system for a two-way traveling shuttle that effectively relieves the problem of oil heating has been proposed, which has become a major technical problem to be solved in the field.

The above information disclosed in this Background section is only for enhancement of understanding of the background of the present disclosure, and thus it may include information that does not constitute a prior art known to those of ordinary skill in the art.

Summary of the invention

The main object of the present invention is to provide a two-way traveling shuttle hydraulic system to solve the technical problem of serious oil heating in the existing hydraulic system of the shuttle bus.

In order to solve the above technical problem, the present invention adopts the following technical solutions:

The invention provides a two-way traveling and swinging vehicle hydraulic system, which comprises two axles arranged on the front and rear sides thereof, two sets of locking bridges capable of respectively locking the two axles, and capable of respectively Two sets of power steering mechanisms for assisting steering of the two axles, wherein the two-way traveling shuttle hydraulic system includes a hydraulic oil tank, a lock bridge circuit and a power steering circuit; the hydraulic oil tank includes a lock bridge fuel tank and a power steering oil tank The power steering oil tank is disposed in the lock axle oil tank; the lock bridge circuit is connected between the lock bridge oil tank and the two sets of lock mechanism; the power steering circuit is connected to the power steering oil tank Between the two sets of power steering mechanisms.

According to an embodiment of the present invention, the lock bridge fuel tank has an oil suction port and a oil return port, and the power steering oil tank has an oil suction port, a oil return port and a top opening, and a top opening of the power steering oil tank is higher than The suction port of the lock bridge fuel tank.

According to another embodiment, the two-way traveling shuttle hydraulic system further includes two oil return filters and/or two radiators; the two oil return filters are respectively disposed on the lock circuit and the lock a connection point of the oil return port of the bridge tank and a connection point between the power steering circuit and the oil return port of the power steering oil tank; the two heat sinks are respectively disposed in the lock bridge circuit and the lock bridge fuel tank a connection of the oil return port and a connection of the power steering circuit to the oil return port of the power steering oil tank.

According to another embodiment, the hydraulic oil tank further includes a liquid level liquid temperature meter; the liquid level liquid temperature meter is disposed on the lock bridge oil tank, and the liquid level height corresponding to the lowest liquid level of the liquid level liquid temperature meter Equal to the height at the top opening of the power steering tank.

According to another embodiment, the power steering oil tank is fixed to an inner wall of the lock axle oil tank, the power steering oil tank shares the inner wall with the lock axle oil tank, and the oil suction port of the lock axle oil tank is disposed at The inner wall is located below the power steering oil tank, and the oil suction port of the power steering oil tank is disposed at a position corresponding to the inner wall corresponding to the power steering oil tank.

According to another embodiment, a first partition is disposed in the lock axle oil tank to divide the lock bridge oil tank into two chambers, and the first partition plate is provided with a first perforation to communicate the Two chambers, the power steering oil tank being disposed in one of the chambers, the first perforation having a height lower than a height of the power steering tank.

According to another embodiment, the lock bridge fuel tank has a top plate, and the oil return port of the lock bridge oil tank and the oil return port of the power steering oil tank are disposed on the top plate, and the oil return of the power steering oil tank a port is located above one of the two chambers of the lock axle oil tank and above the power steering oil tank, the oil return port of the lock bridge oil tank is located at the lock bridge oil The box is above the other of the two chambers.

According to another embodiment, a second baffle is disposed in the power steering oil tank to divide the power steering oil tank into two cavity slots, and the second partition plate is provided with a second perforation to communicate the Two chamber slots.

According to another embodiment, the lock bridge circuit includes a lock bridge pressure line, a lock bridge return line, and a lock bridge electromagnetic reversing valve; a lock bridge pressure line connected to the lock bridge tank and the two groups a first oil pump is installed on the lock bridge pressure line between the lock mechanism, the first oil pump is used for pumping oil from the lock bridge tank to the lock mechanism; the lock bridge return line is connected to Between the two sets of locking mechanism and the lock axle oil tank; a lock bridge electromagnetic reversing valve is mounted on the lock bridge pressure line to selectively conduct one of the two sets of lock bridge mechanisms Oil road.

According to another embodiment, the lock bridge circuit further includes a squib emergency device; the squib emergency device is disposed on the lock bridge pressure line, and is located at the lock bridge pressure line and the lock mechanism The squib emergency device includes a solenoid valve and a pressure relay; the solenoid valve selectively connects or disconnects the lock bridge pressure line; the pressure relay can control the solenoid valve, the lock bridge When the pressure value of the pressure line is lower than a lower limit pressure value of the explosion-proof tube, the pressure relay controls the electromagnetic valve to cut off the lock bridge pressure line.

According to another embodiment, the lock bridge circuit further includes an explosion-proof pipe experimental device; the explosion-proof pipe test device is disposed in the lock bridge pressure line, and is located between the squib emergency device and the lock mechanism The explosion-proof tube experimental device includes an experimental oil tank and a shut-off valve: the experimental oil tank is connected to the lock bridge pressure line through an experimental pipeline; the cut-off valve is disposed in the experimental pipeline to selectively open Or cut off the experimental line.

According to another embodiment, the lock bridge circuit further includes a pressure compensation device; the pressure compensation device includes a liquid filling valve and an accumulator; the liquid filling valve is disposed on the lock bridge pressure line, and is located at the And between the lock bridge electromagnetic reversing valve and the first oil pump, when the pressure value of the lock circuit reaches a working upper limit pressure value, the liquid filling valve adjusts the lock bridge pressure line to release pressure; When the pressure value of the lock bridge circuit reaches a working lower limit pressure value, the liquid filling valve adjusts the lock bridge pressure line to perform pressure compensation; the accumulator is connected to the liquid filling valve to be in the lock bridge When the pressure value of the circuit reaches the working upper limit pressure value, the lock circuit is held.

According to another embodiment, the lock bridge circuit further includes a pressure alarm device and/or a pressure safety device; the pressure alarm device is disposed in the lock bridge circuit, so that the pressure value in the lock bridge circuit is lower than a safety Alarming when the lower limit pressure value is provided; the pressure safety device is disposed at a position where the lock bridge pressure line is connected to the first oil pump to perform when the pressure value of the lock bridge circuit is higher than a safety upper limit pressure value Overflow, limiting the pressure value of the lock bridge circuit continues to rise.

According to another embodiment, the lock-bridge electromagnetic reversing valve is a positionally located electromagnetic reversing valve.

According to another embodiment, the power steering circuit includes a power steering pressure line and a power steering return line. And a power steering electromagnetic reversing valve; a power steering hydraulic pressure line connected between the power steering oil tank and the two sets of power steering mechanisms, wherein the power steering pressure line is equipped with a second oil pump, the second An oil pump is used for pumping oil from the power steering oil tank to the power steering mechanism; a power steering oil return line is connected between the two power steering mechanisms and the power steering oil tank (12); and a power steering electromagnetic reversing valve Provided on the power steering pressure pipeline to selectively conduct an oil passage of one of the two sets of power steering mechanisms.

According to another embodiment, the two-way traveling shuttle hydraulic system further includes an emergency hydraulic system; the emergency hydraulic system includes an emergency oil pump and an emergency electromagnetic reversing valve; the emergency electromagnetic reversing valve selectively connects the lock bridge The fuel tank and the lock bridge circuit and at least one of the lock axle fuel tank and the power steering circuit cause the emergency oil pump to supply oil to at least one of the lock bridge circuit and the power steering circuit.

According to the above technical solution, the utility model has the beneficial effects that the hydraulic system of the two-way traveling and swinging vehicle proposed by the invention combines the fuel tank of the two-way traveling swing hydraulic lock system with the fuel tank of the hydraulic power steering system into a common hydraulic oil tank. The problem that the hydraulic temperature of the hydraulic power steering system is too high is solved, and the hydraulic system of the two-way traveling shuttle is simplified. At the same time, through the structural design of the power steering oil tank in the lock axle fuel tank, the impact of one of the two hydraulic systems of the lock bridge and the power steering is reduced, and the impact on the other hydraulic system is improved, and the whole vehicle is in operation. Security in the middle.

The above and other objects, features and advantages of the present invention will become more apparent from

DRAWINGS

1 is a system diagram of an embodiment of a hydraulic system for a two-way traveling shuttle vehicle according to the present invention;

2 is a top plan view of a hydraulic oil tank of an embodiment of a hydraulic system for a two-way traveling shuttle vehicle according to the present invention;

Figure 3 is a schematic view of the direction A in Figure 2;

Figure 4 is a schematic view of the B direction of Figure 2;

Figure 5 is a schematic view of the C direction of Figure 2;

6 is a schematic view showing a B direction of a first partition of a hydraulic oil tank according to an embodiment of a hydraulic system for a two-way traveling shuttle vehicle according to the present invention;

Figure 7 is a schematic view showing the C direction of the second partition of the hydraulic oil tank of the hydraulic system of the two-way traveling shuttle truck of the present invention;

8 is a graph showing an explosion-proof tube experiment of an explosion-proof tube experiment of an embodiment of a hydraulic system for a two-way traveling shuttle vehicle according to the present invention.

Among them, the reference numerals are as follows:

10, axle; 20, lock axle cylinder; 30, steering gear; 1, hydraulic tank; 11, lock axle fuel tank; 111, oil suction port; 112, oil return; 1121, oil return filter installation; 113; first partition; 1131, first perforation; 12, power steering oil tank; 121, oil suction port; 122, oil return port; 1221, oil return filter mounting portion; 123, second partition; Second perforation; 13, liquid level liquid temperature gauge; 21, lock bridge electromagnetic reversing valve; 221, solenoid valve; 222, pressure relay; 231, liquid filling valve; 232, accumulator; 241, pressure relay; Buzzer; 25, safety valve; 26, first oil pump; 31, power steering electromagnetic reversing valve; 32, second oil pump; 42, emergency oil pump; 43, emergency electromagnetic reversing valve.

detailed description

Example embodiments will now be described more fully with reference to the accompanying drawings. However, the example embodiments can be embodied in a variety of forms and should not be construed as being limited to the embodiments set forth herein. To those skilled in the art. The same reference numerals in the drawings denote the same or similar structures, and thus their detailed description will be omitted.

It should be noted that, in the description of the specification, each numerical unit is described in the form of a letter or a number, for example, a pressure unit megapascal (MPa), a time unit minute (min), a second (s), and a distance unit meter (m). ), millimeters (mm), speed units per kilometer per hour (Km/h), volume unit liters (L), etc., do not limit the application of the invention in other embodiments. Some embodiments of the present invention will be further described below with reference to the accompanying drawings.

As shown in FIG. 1, the two-way traveling shuttle hydraulic system proposed by the present invention can be applied to a two-way traveling shuttle. The two-way traveling shuttle has two driving sides, namely, a head, that is, a main driving side and a b-head, that is, a passenger's side, which is also called a front and rear side of a two-way traveling shuttle, and each side of the driving side has a vehicle. The bridge 10 (the front axle is usually a steering axle and the rear axle is usually a steering axle), and each axle 10 is provided with a locking mechanism and a power steering mechanism. Specifically, for an axle 10, a lock mechanism is disposed at a position corresponding to two wheels on both sides thereof, for example, a lock cylinder 20, and one set of lock mechanisms is two lock bridges on the same axle 10. Cylinder 20. The locking mechanism is used to lock the wheel corresponding to the side, that is, the axle 10 is locked. At the same time, each axle 10 is separately provided with a power steering function by a set of power steering mechanisms, such as a steering gear 30 with a steering chain. When the driver is driving in one of the a head and the b head, the driver operates the steering wheel on the driving side, the side axle 10 is turned by the power steering mechanism, and the other side axle 10 is locked by the bridge. The hydraulic pressure lock of the mechanism is positive and the tire maintains a linear motion. Among them, the lock mechanism supplies oil through the lock bridge hydraulic system, and the power steering mechanism supplies oil through the power steering hydraulic system.

As shown in FIG. 1 and FIG. 2, the hydraulic system of the two-way traveling and swinging vehicle proposed by the present invention (hereinafter referred to as a hydraulic system) An embodiment of the invention. In the present embodiment, the hydraulic system can be used for both the lock bridge and the power steering of the two-way traveling shuttle. Wherein, the hydraulic system mainly comprises a hydraulic oil tank 1 with a lock axle oil tank 11 and a power steering oil tank 12, a lock bridge circuit, a power steering circuit and an emergency hydraulic system. Among them, the lock-bridge circuit and the lock-bridge fuel tank 11 and the lock-and-bridge mechanism together form a lock-bridge hydraulic system, and the power-assisted steering circuit and the power steering oil tank 12 and the power steering mechanism form a power steering hydraulic system.

As shown in FIGS. 1 to 3, in the present embodiment, the hydraulic oil tank 1 mainly includes a lock-up oil tank 11 and a power steering oil tank 12 provided in the lock-up oil tank 11. The lock axle oil tank 11 and the power steering oil tank 12 each have an oil suction port, a oil return port, and a partition plate (a first partition plate 113 and a second partition plate 123, respectively). Moreover, the power steering oil tank 12 also has a top opening structure, that is, the power steering oil tank 12 is actually an oil groove structure, and its top opening height is higher than the height of the oil suction port 111 of the lock bridge oil tank 11. The purpose of this structural design is that when the liquid level in the lock axle tank 11 is high, for example, higher than the top opening of the power steering tank 12, the lock axle tank 11 and the power steering tank 12 are actually one tank; when the lock tank 11 When the inner liquid level is lowered below the top opening of the power steering oil tank 12 and higher than the oil suction port 111 of the lock axle oil tank 11, the lock axle oil tank 11 and the power steering oil tank 12 respectively operate independently; when the hydraulic circuit connected to the lock axle oil tank 11 is If the leakage or other reasons cause the liquid level of the lock-up oil tank 11 to drop below its oil suction port, the liquid level of the power steering oil tank 12 will not fall due to the leakage of the hydraulic circuit connected to the lock-up oil tank 11, and can still be used normally; When the hydraulic circuit connected to the power steering tank 12 is leaked or otherwise causes the liquid level of the power steering oil tank 12 to drop, the liquid level of the lock throttle tank 11 is not lowered to the lock due to the leakage of the hydraulic circuit connected to the power steering oil tank 12. The oil suction port 111 of the bridge tank 11 is below, so that the lock tank 11 can still be used normally.

As shown in FIGS. 2, 3, 6, and 7, the first partition plate 113 is vertically disposed inside the lock-up oil tank 11, and the lock-up oil tank 11 is partitioned into two chambers. A first through hole 1131 is opened in the first partition plate 113 to connect the two chambers. Moreover, the opening height of the first through hole 1131 is lower than the height of the power steering oil tank 12 to ensure sufficient mixing and heat exchange of the hydraulic oil in the two oil tanks. In addition, the second partition plate 123 is vertically disposed inside the power steering oil tank 12, and the power steering oil tank 12 is partitioned into two chamber slots. A second through hole 1231 is defined in the second partition plate 123 to connect the two cavity grooves. In other embodiments, the number and position of the first through holes 1131 are not unique and can be flexibly adjusted.

As shown in FIGS. 2 and 3, the power steering oil tank 12 is fixed to an inner wall of the locker oil tank 11, that is, the power steering oil tank 12 and the lock axle oil tank 11 share the inner wall. The oil suction port 111 of the lock axle oil tank 11 is disposed at a position where the inner wall is located below the power steering oil tank 12, and the oil suction port 121 of the power steering oil tank 12 is disposed at a position where the inner wall corresponds to the power steering oil tank 12. In addition, the lock axle oil tank 11 has a top plate, the oil return port 112 of the lock axle oil tank 11 and the oil return port 122 of the power steering oil tank 12 are all disposed on the top plate, and the oil return port 122 of the power steering oil tank 12 is located at the lock bridge oil tank 11 Above one of the chambers, and corresponding to the upper position of the power steering oil tank 12, the oil return port 112 of the lock axle oil tank 11 is located at the lock bridge oil The tank 11 is above the other of the two chambers. In other embodiments, for example, when neither the lock axle oil tank 11 nor the power steering oil tank 12 is provided with a partition plate, the oil return port 112 of the lock axle oil tank 11 can flexibly select the opening position on the top plate, but it should be ensured that it is not in the power steering oil tank. Above the 12, the position of the oil return port 122 of the power steering oil tank 12 can also be appropriately adjusted, but it should be ensured that it is located above the top opening of the power steering oil tank 12 to return oil.

In addition, as shown in FIG. 2, in the present embodiment, the oil return port 112 of the lock cylinder tank 11 and the oil return port 122 of the power steering oil tank 12 are respectively provided with oil return

filter mounting portions

1121, 1221 for mounting separately. Two return oil filters. The two oil return filters are respectively disposed in the lock return oil return line of the lock bridge circuit and the power steering return oil return line of the power steering circuit to filter the oil return of the two circuits respectively. Moreover, the top of the lock-up oil tank 11 is further provided with a mounting portion 1122 for mounting an air cleaner, which is substantially the same as the conventional structure, and will not be described herein.

In addition, as shown in FIG. 2, in the present embodiment, a lock radiator is provided on the lock return oil return line of the lock bridge circuit and the power steering return oil return line of the power steering circuit, and the two heat sinks are respectively located at two backs. The upstream direction of the oil filter provides the function of filtering the oil before it is cooled. In other embodiments, the lock circuit and the return line of the power steering circuit may be connected as a return oil main pipe, and after the radiator and the oil return filter are installed on the oil return main pipe, respectively, the lock is connected to the lock The oil return port 112 of the axle oil tank 11 and the oil return port 122 of the power steering oil tank 12, other flexible changes of the piping design are not described herein.

It should be noted that the oil return filter and the heat sink proposed in the present embodiment are merely illustrative. In other embodiments, taking the lock bridge circuit as an example, the oil return filter may be separately provided, or the heat sink may be separately provided, that is, the heat sink may be installed on the oil return line of the lock bridge oil tank 11, or the oil return filter may be set. In the direction of the upper direction of the radiator, it is not limited to the embodiment, but it is preferable to set both the oil return filter and the radiator at the connection of the lock circuit and the oil return port 112 of the lock cylinder 11 or The power steering circuit is connected to the return port 122 of the power steering oil tank 12.

In addition, as shown in FIG. 4, in the present embodiment, the lock level tank 11 is provided with a liquid level liquid temperature gauge 13 whose liquid level height corresponding to the lowest liquid level is equal to the height at the top opening of the power steering oil tank 12. That is, when the liquid level in the lock axle tank 11 drops below the lowest reading of the liquid level liquid gauge 13, the lock axle tank 11 and the power steering tank 12 operate as two separate tanks.

The existing hydraulic power steering system usually adopts a vehicle steering oil tank as a fuel tank. Since the steering oil tank of the vehicle has a small volume of oil storage, generally 2 liters to 2.5 liters, the two-way shuttle heads and the b-heads are each equipped with a power steering. The device, thus the steering hydraulic system, has a long hydraulic line, generally reaching about 10 meters, and there is no cooling and cooling device in the hydraulic circuit. The above factors cause the hydraulic oil to generate a large amount of heat when flowing in the existing steering system, and the temperature cycle is increased, causing the hydraulic system to seal and aging, and gradually leaking and the like. The invention eliminates the steering oil can, and the power steering oil tank 12 communicating with the power steering circuit is combined with the lock axle oil tank 11 communicating with the lock bridge circuit to form a common hydraulic oil tank 1 having a large volume, for example, The volume of the lock axle tank 11 can reach 30 liters, and the volume of the power steering tank 12 can be designed to be 5 liters. At the same time, the radiator is arranged at the same time as the power steering return oil pipeline and the lock bridge oil return pipeline, or the two oil return pipelines are shared and returned to the oil through the radiator to enhance the heat dissipation of the oil in the oil return pipeline. The increase of the volume of the fuel tank and the technical measures of returning oil to the oil return pipeline through the radiator effectively solve the problem of aging of the original parts and oil leakage caused by the excessive oil temperature of the existing hydraulic power steering system.

In the normal operation of the hydraulic oil tank 1 of the present invention, the liquid level of the lock-up oil tank 11 is above the minimum liquid level of the liquid level liquid temperature meter 13, and the lock-up oil tank 11 is mixed with the oil in the power steering oil tank 12. The hydraulic oil radiated by the radiator returns to the lock-up oil tank 11 and the power steering oil tank 12, and the hydraulic oil fully exchanges heat, which reduces the oil temperature of the power steering oil tank 12, and effectively solves the problem that the hydraulic oil temperature of the existing steering hydraulic system is too high. The problem. When the liquid level in the lock axle tank 11 is lowered to the lowest liquid level of the liquid level liquid temperature gauge 13, that is, below the maximum liquid level of the power steering oil tank 12, the lock axle oil tank 11 and the power steering oil tank 12 become two independent fuel tanks. At this time, since the volume of the power steering oil tank 12 is larger than that of the existing power steering hydraulic oil tank, the heat dissipation area is large, and the heat dissipation effect is also good.

In addition, the design of the power steering oil tank 12 embedded in the lock axle oil tank 11 can also solve the influence of the existing lock bridge or the power steering hydraulic system on another hydraulic system after the explosion occurs. For example, after the hose of the hydraulic pump pressure port of the lock bridge circuit is squished, the hydraulic oil in the lock bridge tank 11 is exhausted through the squib side, but the hydraulic oil in the power steering tank 12 is not reduced. The design scheme effectively reduces the risk of the hydraulic system after the pipe bursting, and avoids the simultaneous failure of the lock bridge and the power steering function caused by the pipe burst, thereby improving the safety and reliability of the vehicle operation.

As shown in FIG. 1 , in the present embodiment, the lock bridge circuit mainly includes a lock bridge pressure line, a lock bridge return line, a lock bridge electromagnetic reversing valve 21 , a squib emergency device, an explosion-proof tube experimental device, and a pressure compensating device. , pressure alarm device and safety valve 25. Wherein, one end of the lock bridge pressure line is connected to the oil suction port 111 of the lock bridge oil tank 11 , and the other end has two interfaces, which are respectively connected to the two sets of lock bridge mechanisms, that is, each set of lock bridge mechanism includes two lock bridge cylinders 20, To lock the two wheels of the same axle 10 respectively, a first oil pump 26 is mounted on the lock axle pressure line for pumping oil to the lock mechanism. One end of the lock bridge oil return line is connected to the oil return port 112 of the lock bridge oil tank 11, and the other end has two interfaces, which are respectively connected to the two sets of lock bridge mechanisms. The lock bridge electromagnetic reversing valve 21 is disposed on the lock bridge pressure line to selectively conduct the oil path of one of the two sets of lock mechanisms.

The sudden decrease of the hydraulic system of the existing shuttle car is mainly caused by the following reasons: the hose connecting the lock cylinder 20 is squished, causing the hydraulic oil to flow out through the squib side, and the hydraulic system cannot establish the pressure (the hydraulic cylinder is usually 300 from the ground). About millimeters, it is the smallest part of the vehicle's ground clearance, and the pipeline is prone to bursting. The electrical fault causes the H-type three-position four-way electromagnetic reversing valve (the traditional double-headed shuttle car adopts the H-type three-position four-way electromagnetic reversing valve) to lose power, and the spool has a neutral discharge. In view of the above problem, as shown in FIG. 1 , in the present embodiment, the squib emergency device is disposed in the lock bridge pressure line, and is located at the communication between the lock bridge pressure line and the lock mechanism, that is, the lock bridge pressure line and The connection of each lock cylinder 20 is. Burst tube The emergency device includes a solenoid valve 221 for selectively connecting or disconnecting the lock bridge pressure line, and a pressure relay 222 for controlling the solenoid valve 221, and the pressure value of the lock bridge pressure line is lower than an explosion-proof When the tube lower limit pressure value (for example, 9 MPa), the pressure relay 222 controls the solenoid valve 221 to cut the lock bridge pressure line. It should be noted that, in the present embodiment, the lock bridge electromagnetic reversing valve 21 is preferably a two-position four-way electromagnetic reversing valve with positioning, that is, the lock bridge pressure line is divided into four two at the lock bridge electromagnetic reversing valve 21 The stage lock bridge pressure line, that is, the electromagnetic reversing valve has two potentials, each potential corresponding to two secondary lock bridge pressure lines to respectively connect to the lock mechanism on the front and rear side axles 10 of the shuttle bus. In summary, in the present embodiment, the number of the squib emergency devices is four, that is, four solenoid valves 221 and four pressure relays 222 are respectively disposed on the four secondary lock bridge pressure lines. In other embodiments, a set of squib emergency devices may be disposed on the secondary lock bridge pressure line that communicates with one of the lock cylinders 20 of each of the lock mechanisms, or according to the lock bridge pressure line and the lock bridge. Other pipeline installation forms at the connection of the mechanism, correspondingly changing the setting mode of the squib emergency device, are not limited thereto, but it should be ensured that the above-mentioned explosion-proof pipe function is provided for the front and rear axles 10 of the shuttle bus.

It should be noted that the two-position four-way electromagnetic reversing valve with positioning selected in the embodiment maintains the corresponding electromagnet in the left or right position, and the technical feature actually plays the role of double insurance. It avoids the situation that the positioning device of the lock-bridge electromagnetic reversing valve 21 cannot be kept in the working position after the failure of the positioning device. At this time, the electromagnet is often energized, the electromagnetic suction keeps the valve core in the working position, and the electromagnetic system is prevented from causing electromagnetic failure. The iron loses power and it cannot be kept in the working position, at which point the positioning device keeps the spool in the working position. The selection of the above-mentioned lock-bridge electromagnetic reversing valve 21 avoids the hydraulic system failure and the hydraulic lock caused by the valve core of the lock-bridge electromagnetic reversing valve 21 of the existing double-headed swing truck lock hydraulic system not being maintained in the normal working position. The problem of sudden drop in bridge pressure. In other embodiments, other types of electromagnetic reversing valves may be flexibly selected according to the pipeline arrangement form in the lock bridge circuit, but electromagnetic reversing valves with positioning functions are preferred, and are not limited thereto.

As shown in FIG. 1 , in the present embodiment, the explosion-proof tube experimental device is disposed on the lock bridge pressure line and is located between the squib emergency device and the lock mechanism. The explosion-proof tube experimental device includes an experimental oil tank and a shut-off valve, and the experimental oil tank is connected to the lock bridge pressure line through an experimental pipeline, and the cut-off valve is disposed in the experimental pipeline to selectively open or cut the experimental pipeline. In view of the above structure, the present invention designs a squib test and simulates a squib for each secondary lock bridge pressure line to ensure that the squib emergency device can effectively prevent the squib when the vehicle is running. Taking one of the secondary lock-bridge pressure pipelines as an example, the schematic diagram of the design of the explosion-proof pipe test can be referred to Figure 1. At the interface of the lock-up cylinder 20, a test pipeline is connected with the shut-off valve, and the other end of the shut-off valve is connected. tank. After the secondary lock bridge pressure line reaches the normal lock bridge pressure of 15 MPa, manually open the shut-off valve to simulate the burst of the line. After the squib, the solenoid valve 221 on the secondary lock bridge pressure line automatically cuts off the branch, and the squib test curve shown in FIG. 8 is obtained. In the above experiment, the normal locking pressure of the hydraulic system is 15 MPa. The pressure relay 222 sets the pressure to 9 MPa. The key parameter in the squib test is the pressure setting value of the pressure relay 222. Generally, after 2 seconds to 3 seconds after the squib occurs, the solenoid valve 221 operates to cut off the squib circuit. If the pressure setting value is too high, the system may drop the pressure to the set value for other reasons and cause a false tube explosion. In fact, the system does not explode. If the pressure setting value is too low, even if the system bursts, it cannot be detected, which may cause the oil in the tank to flow through the squib side.

As shown in FIG. 1, in the present embodiment, the pressure compensating device mainly includes a liquid filling valve 231 and an accumulator 232. The liquid filling valve 231 is disposed on the lock bridge pressure line and is located between the lock bridge electromagnetic reversing valve 21 and the first oil pump 26 . When the pressure value of the lock bridge circuit reaches a working upper limit pressure value (for example, 15 MPa), the liquid filling valve 231 adjusts the lock bridge pressure line to release pressure, and when the pressure value of the lock bridge circuit reaches a lower working pressure value (for example) At 12.5 MPa, the filling valve 231 adjusts the lock-bridge pressure line for pressure compensation. The accumulator 232 is connected to the filling valve 231 for holding the lock circuit when the pressure value of the lock circuit reaches the upper working pressure value (for example, 15 MPa).

As shown in FIG. 1 , in the present embodiment, the pressure alarm device is disposed in the lock bridge pressure line, such as a pressure relay 241 , so that the pressure value in the lock bridge circuit is lower than a safe lower limit pressure value (for example, 9 MPa). When an alarm occurs. Specifically, a buzzer 242 and an alarm light mounted on the dashboard of the vehicle are connected by a pressure relay 241. When the pressure in the lock bridge circuit is lower than 9 MPa, the pressure relay 241 sends an electric signal, the buzzer 242 issues an alarm and the alarm light illuminates. In other embodiments, other devices or electrical components may be used instead of the above-mentioned pressure alarms, and the function of monitoring the pressure of the lock circuit is not limited thereto.

As shown in FIG. 1 , in the present embodiment, the safety valve 25 is disposed at a position where the lock pressure line is connected to the first oil pump 26 , that is, the first oil pump 26 passes the hydraulic oil in the lock tank 11 through the lock tube pressure tube. The location where the road is pumped. The safety valve 25 is mainly used for overflowing when the pressure value of the lock bridge circuit is higher than a safety upper limit pressure value (for example, 18 MPa), that is, the oil supply to the lock bridge pressure line of the first oil pump 26 is cut off to limit the lock. The pressure value of the bridge circuit continues to rise. In other embodiments, other devices may be used instead of the safety valve 25 as a pressure safety device to monitor the pressure of the lock circuit, and are not limited thereto.

It should be noted that the descriptions of the above-mentioned pressure alarm device and the safety valve 25 in the present embodiment are merely exemplary, and the specific arrangement manner and the installation position can be flexibly adjusted according to actual needs. Further, only the pressure alarm device may be provided, or only the safety valve 25 may be provided, and the pressure alarm device and the safety valve 25 may be provided at the same time, which are not limited to the embodiment.

As shown in FIG. 1 , taking the embodiment as an example, the working principle of the pressure compensating device, the pressure alarm device and the safety valve 25 is as follows: the filling valve 231 sets the working upper limit pressure value to 15 MPa, and the working lower limit pressure value is At 12.5 MPa, the safety valve 25 sets a safety upper limit pressure of 18 MPa. When the lock bridge hydraulic system works normally, the pressure of the lock bridge circuit rises. At 15 MPa, the N port of the filling valve 231 is connected to the P port, and the first oil pump 26 is discharged from the N port through the lock pipe pressure line, and the pressure becomes zero. The S2 port of the liquid filling valve 231 is connected to the accumulator 232 and the lock bridge circuit, and the accumulator 232 plays a pressure maintaining function in the lock bridge circuit, and the lock bridge pressure is maintained at 15 MPa. When the lock bridge circuit is reduced to 12.5 MPa due to pipeline leakage or other reasons, the P port of the liquid filling valve 231 is connected to the S2 port, and the first oil pump 26 supplements the pressure of the lock bridge circuit through the lock bridge pressure line. Discharge again until the pressure rises to 15 MPa. The pressure relay 241 sets the safety lower limit pressure value to 9 MPa. When the pressure is lower than 9 MPa, an electric signal is issued, the instrument panel lock bridge pressure low alarm light is on, and the buzzer 242 alarms. It should be noted that the above-mentioned working upper limit pressure value, working lower limit pressure value, safety upper limit pressure value and safety lower limit pressure value can be set according to actual conditions, and are not limited thereto.

As shown in FIG. 1 , in the present embodiment, the power steering circuit mainly includes a power steering pressure pipeline, a power steering return oil pipeline, and a power steering electromagnetic reversing valve 31 . Wherein, one end of the power steering pressure line is connected to the oil suction port 121 of the power steering oil tank 12, and the other end has two interfaces, which are respectively connected to two sets of power steering mechanisms, for example, two steering gears 30, and the power steering pressure pipeline is installed with the first Two oil pump 32. One end of the power steering return oil line is respectively connected to the two steering gears 30, and the other end is connected to the oil return port 122 of the power steering oil tank 12. The power steering electromagnetic reversing valve 31 is disposed on the power steering pressure line to selectively conduct the oil path of one of the two steering gears 30.

As shown in FIG. 1 , the above-mentioned power steering hydraulic system, that is, the working principle of the power steering circuit is: when the head is driving, the power steering electromagnetic reversing valve 31 is operated to the left position, that is, the electromagnet DTA is energized, and the second oil pump 32 is the same. The side power steering mechanism supplies oil and vice versa. When there is no need to turn, the pressure in the power steering circuit is zero, and the power steering hydraulic system is discharged through the return port of the steering mechanism. When the driver turns the steering wheel, the pressure of the power steering hydraulic system rises, and the steering gear 30 performs power steering through the steering chain.

For example, when the lock bridge electromagnetic reversing valve 21 in the lock bridge circuit selects to supply oil to the lock mechanism on the side axle 10 of the shuttle bus, that is, the main driving side of the shuttle bus realizes the lock bridge, the driver is When the passenger's side drives the vehicle, the steering electromagnetic reversing valve of the power steering circuit selects to supply oil to the power steering mechanism on the b-head side. When the driver controls the steering wheel on the passenger's side, the steering gear 30 on the side cooperates with the steering wheel pair. The side axle 10 provides the function of power steering. When the lock bridge electromagnetic reversing valve 21 in the lock bridge circuit is converted to supply oil to the lock mechanism on the axle 10 on the side of the shuttle bus b, that is, the passenger side of the shuttle car realizes the lock bridge, and the driver is in the main When the driving side drives the vehicle, the steering electromagnetic reversing valve of the power steering circuit is switched to supply oil to the power steering mechanism on the side of the a head. When the driver controls the steering wheel of the main driving side, the steering gear 30 of the side cooperates with the steering wheel pair. The side axle 10 provides the function of power steering.

In the use of the existing shuttle bus, the engine cannot be operated normally due to the vehicle failure. In an emergency, the tractor needs to be towed away from the maintenance vehicle to the maintenance site for maintenance. Since the steering pump mounted on the engine cannot operate normally, only the steering wheel can be manually turned, and the steering of the vehicle is difficult. In view of the above problem, as shown in FIG. 1, in the present embodiment, The emergency hydraulic system mainly includes an emergency oil pump 42 and an emergency electromagnetic reversing valve 43. The emergency electromagnetic reversing valve 43 is configured to selectively communicate at least one of the lock axle oil tank 11 and the lock bridge circuit and the power steering circuit, so that the emergency oil pump 42 supplies oil to the lock circuit or the power steering circuit, or simultaneously locks the bridge The circuit and the power steering circuit supply oil. Further, in order to avoid the impact of the failure of the lock axle tank 11 on the emergency hydraulic system, an emergency fuel tank may be provided to selectively connect the emergency electromagnetic reversing valve 43 to at least the emergency fuel tank and the lock bridge circuit and the power steering circuit. In one case, the emergency oil pump 42 supplies oil to at least one of the lock bridge circuit and the power steering circuit. In other embodiments, the hydraulic components in the emergency hydraulic system may also be selected from other types, and are not limited thereto.

Taking the embodiment as an example, when the lock hydraulic system fails and the system is paralyzed, the emergency electromagnetic reversing valve 43 selects to connect the lock bridge fuel tank 11 or the emergency fuel tank to the lock bridge circuit through the emergency pipeline, and through the emergency oil pump 42 The lock bridge circuit, that is, the lock mechanism, supplies oil and realizes the emergency lock function. Preferably, the communication position between the emergency line and the lock bridge circuit is the position between the pressure compensating device on the lock bridge pressure line and the safety valve 25, that is, the position between the lock bridge electromagnetic reversing valve 21 and the first oil pump 26. When the power steering hydraulic system fails and the system is paralyzed, the emergency electromagnetic reversing valve 43 selects the auxiliary steering oil tank 12 or the emergency fuel tank to communicate with the power steering circuit through the emergency pipeline, and supplies oil to the power steering mechanism through the emergency oil pump 42 Emergency power steering function. Preferably, the communication line between the emergency line and the power steering circuit is a position between the power steering electromagnetic reversing valve 31 and the second oil pump 32 on the power steering pressure line. When the lock hydraulic system and the power steering hydraulic system fail at the same time, the emergency electromagnetic reversing valve 43 selects the hydraulic oil tank 1 or the emergency fuel tank to communicate with the lock circuit and the power steering circuit through the emergency pipeline, and passes the emergency oil pump. 42 The oil is simultaneously supplied to the lock mechanism and the power steering mechanism to provide the emergency lock function and the emergency power steering function. The above emergency hydraulic system not only solves the problem of difficulty in steering when the vehicle is faulty, but also solves the safety hazard of the failure of the lock bridge when the vehicle fails.

It should be noted that when the emergency oil pump 42 is powered as an emergency power source, it works in a short time. Under normal circumstances, when the emergency oil pump 42 replenishes the pressure of the lock-bridge hydraulic system, the continuous working time is the boosting time of the lock-bridge hydraulic system, that is, the pressure is raised from the lower working pressure value (for example, 12.5 MPa) to the upper working pressure value ( For example, 15 MPa), the boost time is usually within 5 seconds. The lock-bridge hydraulic system generally has a supplementary pressure interval of about 40 minutes. When the emergency oil pump 42 powers the power steering hydraulic system, the continuous working time is the vehicle turning time, and the turning time is usually within 10 seconds. In order to avoid serious heat generation, the continuous working time of the emergency oil pump 42 is required to not exceed the prescribed value. The emergency oil pump 42 selected in the present embodiment requires a continuous working time of no more than 3 minutes, and the actual use situation fully satisfies the continuous working time requirement of the emergency oil pump 42.

Further, in the present embodiment, in order to facilitate the driver's operation, a self-resetting electric lock bridge switch and an electric power steering switch can be mounted on the cab dashboard. After pressing the electric power steering switch, the emergency electromagnetic reversing valve 43 is left (bomb The spring position works and the emergency oil pump powers the steering hydraulic system. After pressing the electric lock bridge switch, the emergency electromagnetic reversing valve 43 is operated in the right position (the electromagnet is energized), and the emergency oil pump supplies power to the lock bridge hydraulic system.

It should be understood that the emergency hydraulic system is not limited to providing emergency protection for the lock-bridge hydraulic system and the power steering hydraulic system, and may selectively provide emergency fuel supply to at least one of the hydraulic systems of the two-way shuttle. At the same time, it provides emergency protection for each hydraulic system of the two-way shuttle bus.

Industrial applicability

The hydraulic system of the two-way traveling and swinging vehicle proposed by the invention solves the problem that the oil temperature of the hydraulic power steering system is too high by combining the fuel tank of the hydraulic locking bridge system of the two-way traveling shuttle with the fuel tank of the hydraulic power steering system as a common hydraulic oil tank. And simplify the hydraulic system of the two-way shuttle bus. At the same time, through the structural design of the power steering oil tank in the lock axle fuel tank, the impact of one of the two hydraulic systems of the lock bridge and the power steering is reduced, and the impact on the other hydraulic system is improved, and the whole vehicle is in operation. Security in the middle. While the invention has been described with respect to the exemplary embodiments illustrated embodiments The present invention may be embodied in a variety of forms without departing from the spirit or scope of the invention. It is to be understood that the invention is not limited to the details. All changes and modifications that come within the scope of the claims or the equivalents thereof are intended to be covered by the appended claims.

Claims

A two-way traveling shuttle hydraulic system includes two axles (10) disposed on front and rear sides thereof, two sets of locking mechanisms capable of locking the two axles (10), respectively Two sets of power steering mechanisms capable of separately assisting the two axles (10), wherein the two-way traveling shuttle hydraulic system includes:

Hydraulic tank (1), including:

Lock bridge fuel tank (11); and

a power steering oil tank (12) disposed in the lock axle fuel tank (11);

a lock bridge circuit connected between the lock axle tank (11) and the two sets of lock mechanisms;

A power steering circuit is connected between the power steering oil tank (12) and the two sets of power steering mechanisms.
The two-way traveling shuttle hydraulic system according to claim 1, wherein the lock-up oil tank (11) has an oil suction port (111) and a oil return port (112), and the power steering oil tank (12) has The oil suction port (121), the oil return port (122) and the top opening, the top opening of the power steering oil tank (12) is higher than the oil suction port (111) of the lock bridge oil tank (11).
The two-way traveling shuttle hydraulic system according to claim 2, wherein the two-way traveling shuttle hydraulic system further comprises:

Two oil return filters respectively disposed at a junction of the lock circuit and the oil return port (112) of the lock axle oil tank (11) and the power steering circuit and the power steering oil tank (12) a connection to the oil return port (122); and/or

Two radiators respectively disposed at a junction of the lock bridge circuit and the oil return port (112) of the lock axle oil tank (11) and oil return of the power steering circuit and the power steering oil tank (12) The junction of the mouth (122).
The two-way traveling shuttle hydraulic system according to claim 2, wherein the hydraulic oil tank (1) further comprises:

a liquid level liquid temperature meter (13) is disposed on the lock bridge oil tank (11), and a liquid level height corresponding to a minimum liquid level of the liquid level liquid temperature meter (13) is equal to a top of the power steering oil tank (12) The height at the opening.
The two-way traveling shuttle hydraulic system according to claim 2, wherein said power steering oil tank (12) is fixed to an inner wall of said lock axle oil tank (11), said power steering oil tank (12) and The lock bridge oil tank (11) shares the inner wall, and an oil suction port (111) of the lock bridge oil tank (11) is disposed at the inner wall and located at a position below the power steering oil tank (12), the power steering An oil suction port (121) of the oil tank (12) is provided at a position where the inner wall corresponds to the power steering oil tank (12).
The two-way traveling shuttle hydraulic system according to claim 2, wherein a first partition (113) is disposed in the lock-up oil tank (11) to divide the lock-up oil tank (11) into two a first chamber (113) is provided with a first perforation (1131) for communicating the two chambers, and the power steering oil tank (12) is disposed in one of the chambers. The height of the first perforation (1131) is lower than the height of the power steering oil tank (12).
The two-way traveling shuttle hydraulic system according to claim 6, wherein the lock-up oil tank (11) has a top plate, a return port (112) of the lock-up oil tank (11), and the power steering The oil return port (122) of the oil tank (12) is disposed on the top plate, and the oil return port (122) of the power steering oil tank (12) is located in one of the two chambers of the lock bridge oil tank (11). Above, and above the power steering oil tank (12), the oil return port (112) of the lock bridge tank (11) is located above the other of the two chambers of the lock bridge tank (11).
The two-way traveling shuttle hydraulic system according to claim 2, wherein a second partition (123) is disposed in the power steering oil tank (12) to divide the power steering oil tank (12) into two a second cavity (1231) is defined in the second partition (123) to communicate the two cavity slots.
The two-way traveling shuttle hydraulic system according to any one of claims 1 to 8, wherein the lock circuit comprises:

a lock bridge pressure line connected between the lock bridge oil tank (11) and the two sets of lock mechanism, wherein the lock oil pressure line is installed with a first oil pump (26), the first oil pump ( 26) for pumping oil to the lock mechanism by the lock axle tank (11);

a lock bridge return line connected between the two sets of lock mechanism and the lock bridge tank (11);

A lock bridge electromagnetic reversing valve (21) is mounted on the lock bridge pressure line to selectively conduct an oil passage of one of the two sets of lock mechanisms.
The two-way traveling shuttle hydraulic system according to claim 9, wherein the lock circuit further comprises:

a squib emergency device, disposed in the lock bridge pressure line, and located at a communication between the lock bridge pressure line and the lock mechanism, the squib emergency device includes:

a solenoid valve (221) selectively connecting or disconnecting the lock bridge pressure line;

a pressure relay (222) capable of controlling the solenoid valve (221), the pressure relay (222) controlling the solenoid valve (221) when a pressure value of the lock bridge pressure line is lower than a lower limit pressure value of the explosion-proof tube ) cutting off the lock bridge pressure line.
The two-way traveling shuttle hydraulic system according to claim 10, wherein the lock circuit further comprises:

The explosion-proof pipe experimental device is disposed between the squib emergency device and the lock-locking mechanism, and the explosion-proof pipe experimental device comprises:

An experimental fuel tank connected to the lock bridge pressure line through an experimental line; and

A shutoff valve is provided in the experimental line to selectively open or shut off the experimental line.
The two-way traveling shuttle hydraulic system according to claim 9, wherein the lock circuit further comprises:

Pressure compensation device, including:

a liquid filling valve (231) is disposed in the lock bridge pressure line and located between the lock bridge electromagnetic reversing valve (21) and the first oil pump (26), and the pressure value of the lock circuit When the working upper limit pressure value is reached, the liquid filling valve (231) adjusts the lock bridge pressure line to relieve pressure; when the pressure value of the lock circuit reaches a lower working pressure value, the liquid filling valve ( 231) adjusting the lock bridge pressure line for pressure compensation; and

An accumulator (232) is coupled to the liquid filling valve (231) to hold the lock circuit when the pressure value of the lock circuit reaches the upper operating pressure value.
The two-way traveling shuttle hydraulic system according to claim 9, wherein the lock circuit further comprises:

a pressure alarm device disposed on the lock bridge pressure line to alarm when a pressure value of the lock bridge circuit is lower than a safe lower limit pressure value; and/or

a pressure safety device is disposed at a position where the lock bridge circuit is connected to the first oil pump (26) to overflow when the pressure value of the lock bridge circuit is higher than a safety upper limit pressure value, and the lock is restricted The pressure value of the bridge circuit continues to rise.
The two-way traveling shuttle hydraulic system according to claim 9, wherein the lock-bridge electromagnetic reversing valve (21) is an electromagnetic reversing valve with positioning.
The two-way traveling shuttle hydraulic system according to any one of claims 1 to 8, wherein the power steering circuit comprises:

a power steering pressure line connected between the power steering oil tank and the two sets of power steering mechanisms, the power steering pressure line is equipped with a second oil pump (32), and the second oil pump (32) Pumping oil to the power steering mechanism by the power steering oil tank (12);

a power steering return line that is in communication between the two sets of power steering mechanisms and the power steering tank (12);

A power steering electromagnetic reversing valve (31) is disposed on the power steering pressure line to selectively conduct an oil passage of one of the two sets of power steering mechanisms.
The two-way traveling shuttle hydraulic system according to any one of claims 1 to 8, wherein the two-way traveling shuttle hydraulic system further comprises:

Emergency hydraulic system, including:

Emergency oil pump (42); and

An emergency electromagnetic reversing valve (43) selectively connecting at least one of the lock axle oil tank (11) and the lock bridge circuit and the lock axle oil tank (11) and the power steering circuit An emergency oil pump (42) supplies oil to at least one of the lock bridge circuit and the power steering circuit.