CN118346669A

CN118346669A - Hydraulic drive system and milling machine

Info

Publication number: CN118346669A
Application number: CN202410552236.XA
Authority: CN
Inventors: 周晓群; 周雄; 赵俊飞
Original assignee: Hunan Sany Zhongyi Machinery Co Ltd
Current assignee: Hunan Sany Zhongyi Machinery Co Ltd
Priority date: 2024-05-07
Filing date: 2024-05-07
Publication date: 2024-07-16

Abstract

The invention provides a hydraulic drive system and a milling machine, wherein the hydraulic drive system comprises: a pump body and a plurality of hydraulic drives; at least two first flow dividing and collecting valves, each first flow dividing and collecting valve is provided with a first flow collecting port and two first flow dividing ports, each first flow dividing port is communicated with the pump body, and each first flow dividing port is communicated with one hydraulic driving piece; and the first control valve can conduct the two first shunt ports of the first shunt current collecting valve under the condition that the two ends of the first control valve are provided with pressure differences. Compared with the prior art that a quarter equivalent flow distributing and collecting valve is utilized, the internal structure of the flow distributing and collecting valve is simplified, the manufacturing difficulty of the flow distributing and collecting valve is reduced, the production cost of the hydraulic driving system is reduced on the premise of ensuring the anti-skid effect, and the production cost of the milling machine with the hydraulic driving system is further reduced.

Description

Hydraulic drive system and milling machine

Technical Field

The invention relates to the technical field of hydraulic driving, in particular to a hydraulic driving system and a milling machine.

Background

Currently, milling machine travel systems generally include a one-pump four-motor drive system and a two-pump four-motor drive system. Wherein, the double pump four motor driving system increases the cost due to the additional pump group.

For a pump four motor drive system, a quarter-split flow valve is typically provided between the pump and motor in the related art. However, the one-to-four flow dividing and collecting valve has a complex structure, high processing difficulty, high price, long supply period and the like. In addition, in the related art, motors are controlled through program differentiation, however, an electric proportional control mode is adopted for driving the motors, the control requirement is high, and meanwhile, a rotating speed sensor is added to each motor, so that the cost is high.

Disclosure of Invention

Embodiments of the present invention aim to solve or improve at least one of the technical problems existing in the prior art.

To this end, a first aspect of an embodiment of the invention provides a hydraulic drive system.

A second aspect of an embodiment of the present invention provides a milling machine.

In view of this, according to a first aspect of an embodiment of the present invention, there is provided a hydraulic drive system including: a pump body and a plurality of hydraulic drives; at least two first flow dividing and collecting valves, each first flow dividing and collecting valve is provided with a first flow collecting port and two first flow dividing ports, each first flow dividing port is communicated with the pump body, and each first flow dividing port is communicated with one hydraulic driving piece; and the first control valve can conduct the two first shunt ports of the first shunt current collecting valve under the condition that the two ends of the first control valve are provided with pressure differences.

The hydraulic driving system provided by the embodiment of the invention comprises a pump body, a plurality of hydraulic driving pieces, at least two first flow distributing and collecting valves and a first control valve, wherein each first flow distributing and collecting valve is provided with a first flow collecting port and two first flow dividing ports, namely, each first flow distributing and collecting valve is a one-to-two equivalent flow distributing and collecting valve.

Each first flow collecting port is communicated with the pump body, and each first flow dividing port is communicated with one hydraulic driving piece, namely, at least two first flow dividing and collecting valves are positioned between the pump body and a plurality of hydraulic driving pieces. Specifically, when the milling machine with the hydraulic driving system advances, hydraulic oil pumped by the pump body respectively enters the first flow collecting port of each first flow distributing and collecting valve, and after equal flow distribution, the hydraulic oil respectively enters each hydraulic driving piece to realize the walking driving of the milling machine. I.e. forward split drive. Alternatively, a reverse split drive, i.e. an equal split by at least two first split and collector valves when the milling machine is in reverse, is also possible.

When the milling machine retreats, hydraulic oil pumped by the pump body flows to the first shunt ports through the hydraulic driving pieces respectively, flows back to the pump body after being respectively collected through the at least two first collecting ports, namely, retreating collecting driving. Alternatively, a forward collecting drive, i.e. a collecting by at least two first collecting and distributing valves during the forward movement of the milling machine, is also possible. The setting can be specifically performed according to actual needs.

The equal flow distribution and collection valve of at least two one-to-two equal flow distribution and collection valves can realize equal flow distribution of hydraulic oil, and an anti-skid effect can be achieved when the milling machine walks. Compared with the prior art that a quarter equivalent flow distribution and collection valve is utilized, the internal structure of the flow distribution and collection valve is simplified, the manufacturing difficulty of the flow distribution and collection valve is reduced, the production cost of a hydraulic driving system is reduced on the premise of ensuring the anti-skid effect, and the production cost of a milling machine with the hydraulic driving system is further reduced.

In addition, the circulation driving of the hydraulic oil is realized by using one pump body, compared with the driving by using double pumps in the related art, the structure of the hydraulic driving system is simplified, and the production cost of the hydraulic driving system is further reduced. Compared with the prior art that the motor is controlled by program differentiation, the control is simple and convenient, and the structure such as a rotating speed sensor is not required to be additionally arranged, so that the production cost of the milling machine with the hydraulic driving system is greatly reduced.

It will be appreciated that the travel speeds of the left and right front wheels differ when the milling machine is turning, such that the rotational speeds of the two hydraulic drives respectively associated with the left and right front wheels differ. The traveling speeds of the left front wheel and the right rear wheel are also different, so that the rotational speeds of the two hydraulic driving pieces respectively connected with the left front wheel and the right rear wheel are different. That is, when the milling machine is turned, the flow rates required for the two hydraulic driving members respectively connected to the two wheels having different traveling speeds are different, resulting in a situation in which the system is prone to pressure holding.

The two first shunt ports of at least one first shunt and flow collecting valve are connected through the first control valve, and when the pressure difference exists at the two ends of the first control valve, the first control valve enables the two first shunt ports of the first shunt and flow collecting valve to be conducted, so that automatic flow compensation is achieved under the steering and flow collecting working condition of the milling machine, the hydraulic driving system is not prone to pressure holding, and the reliability of the hydraulic driving system is improved.

It will be appreciated that, when the milling machine is turning, a pressure differential is created across the first control valve because the flow required by the two hydraulic drives respectively associated with the two wheels of different travel speeds is different.

Optionally, each hydraulic drive is a hydraulic motor.

In addition, the hydraulic driving system provided by the technical scheme of the invention has the following additional technical characteristics:

In some aspects, optionally, the first control valve is a throttle valve.

In the technical scheme, the first control valve is defined as the throttle valve, and it can be understood that when the two ends of the throttle valve are provided with pressure differences, the throttle valve is conducted, so that two first shunt ports of the first shunt and collector valve are conducted, automatic compensation of flow under the steering working condition of the milling machine is realized, and the system is prevented from being pressed.

In addition, the through-flow cross section area of the throttle valve is smaller, so that the flow of hydraulic oil flowing through the throttle valve is smaller even if the throttle valve is conducted, the situation that the milling machine is in running fault due to the fact that most of flow on one side flows to the other side when the milling machine turns is prevented, and stability and reliability in the running process of the milling machine are ensured.

Optionally, the plurality of hydraulic driving members includes at least a first hydraulic driving member and a second hydraulic driving member, the first hydraulic driving member and the second hydraulic driving member being capable of different rotational speeds; the first hydraulic driving piece and the second hydraulic driving piece are respectively communicated with two first shunt ports of one first shunt and flow collecting valve. Alternatively, the first hydraulic drive and the second hydraulic drive are each connected to two wheels of the milling machine.

It will be appreciated that when the milling machine is turning, the two wheels respectively associated with the first and second hydraulic drive members have different travel speeds such that the first and second hydraulic drive members have different rotational speeds, i.e. the flow rates required by the first and second hydraulic drive members are different.

Optionally, the first hydraulic drive and the second hydraulic drive are connected to the left front wheel and the right front wheel, respectively. Or the first hydraulic driving piece and the second hydraulic driving piece are respectively connected with the left front wheel and the right rear wheel.

The two first shunt ports of the first shunt and flow collecting valve are respectively communicated with a first hydraulic driving piece and a second hydraulic driving piece which can have different rotating speeds. Because two first shunt ports link to each other through first control valve, when the milling machine turns to, the both ends of first control valve produce pressure differential for two first shunt ports switch on, thereby realize the automatic compensation of flow under the diversity flow operating mode of milling machine turns to, make hydraulic drive system be difficult for taking place the condition of holding down the pressure, promote hydraulic drive system's reliability.

In some embodiments, optionally, the hydraulic driving system further includes a control valve group, where the control valve group is connected to the first collecting port and the two first splitting ports of each first splitting and collecting valve; under the condition that the control valve group is conducted, each first flow distributing and collecting valve is cut off; when the control valve group is closed, each first flow dividing and collecting valve is connected.

In this solution, it is defined that the hydraulic drive system further comprises a control valve group, in particular a control valve group connected to the first manifold of each first flow dividing and collecting valve and to the two first shunt ports of each first flow dividing and collecting valve.

When the control valve group is conducted, each first flow distributing and collecting valve is cut off, and one working condition of the milling machine, optionally, a free wheel working condition can be achieved. When the control valve group is cut off, each first flow distributing and collecting valve is conducted, equal flow distribution and collecting are carried out when the milling machine walks, the anti-skid effect can be achieved, and the other working condition of the milling machine can be achieved, and optionally, the working condition of straight-line running flow distribution and collecting can be achieved.

That is, by switching on or off the control valve group, the switching of the milling machine under various working conditions can be realized, the control is simple and convenient, an external control oil source is not needed, and the production cost of the hydraulic driving system is reduced.

In some technical solutions, optionally, the control valve group includes a plurality of logic valves and a second control valve, where each logic valve includes a first communication port, a second communication port and a control port, the first communication port is communicated with the first collecting port, the second communication port is communicated with the first dividing port, the second control valve is connected with each control port and the pump body, and the second control valve has at least a first working position and a second working position; under the condition that the second control valve is in the first working position, the pump body is communicated with each control port through the second control valve, each logic valve is closed, and each first flow distributing and collecting valve is communicated; under the condition that the second control valve is in the second working position, each control port is communicated with the oil tank through the second control valve, each logic valve is conducted, and each first flow distributing and collecting valve is cut off.

In this technical solution, it is defined that the control valve group includes a plurality of logic valves and a second control valve, specifically, each logic valve includes a first communication port, a second communication port and a control port, the first communication port communicates with the first collecting port, and the second communication port communicates with the first dividing port.

Optionally, the plurality of logic valves includes a first logic valve, a second logic valve, a third logic valve, and a fourth logic valve, wherein the first logic valve is connected to the first manifold of one of the first split-flow and manifold valves and one of the first split-flow ports of the first split-flow and manifold valve, and the second logic valve is connected to the first manifold of the first split-flow and manifold valve and the other first split-flow port.

The third logic valve is connected with the first collecting port of the other first flow distributing and collecting valve and one of the first split-flow ports of the first flow distributing and collecting valve, and the fourth logic valve is connected with the first collecting port of the first flow distributing and collecting valve and the other first split-flow port.

Each logic valve has a control port, optionally the control port of each logic valve communicates with the spring chamber of the logic valve.

The second control valve is connected with each control port and the pump body. Specifically, the second control valve is provided with at least a first working position and a second working position, when the second control valve is in the first working position, the pump body is communicated with the control port of each logic valve through the second control valve, high-pressure oil is communicated with the spring cavity of each logic valve, each logic valve is cut off due to area difference, each first flow dividing and collecting valve is communicated, and the working condition of straight running flow dividing and collecting is entered, and optionally, flow dividing and collecting is carried out in a forward direction and a backward direction. Thereby the milling machine has the anti-skid function.

When the second control valve is in the second working position, each control port is communicated with the oil tank through the second control valve, namely, the spring cavity of each logic valve is communicated with the oil tank to perform pressure relief, so that each logic valve is conducted. Because the flow resistance of the logic valve is smaller than that of the first flow distributing and collecting valve, when the logic valve is conducted, hydraulic oil pumped by the pump body is freely distributed to the logic valves, and then flows to the hydraulic driving pieces through the logic valves respectively without flowing to the first flow distributing and collecting valve, so that the free wheel working condition is realized.

The second control valve is controlled to be in different working positions, so that the logic valve can be switched on or off, and further switching between forward and backward flow distribution and collection and free wheels is realized, the control is simple and convenient, an external control oil source is not needed, and the production cost of a hydraulic driving system and a milling machine with the hydraulic driving system is reduced.

Optionally, the second control valve is a two-position four-way solenoid valve.

In some technical solutions, optionally, the pump body includes a first oil port and a second oil port, the first oil port is communicated with each first collecting port, the second oil port is communicated with each hydraulic driving element, the control valve group further includes a shuttle valve, the shuttle valve includes a first interface, a second interface and a third interface, the first interface is communicated with the first oil port, the second interface is communicated with the second oil port, and the third interface is communicated with the second control valve.

In this technical scheme, it still includes the shuttle valve to have limited the control valves, specifically, the first interface and the second interface of shuttle valve communicate with the first hydraulic fluid port and the second hydraulic fluid port of the pump body respectively. It is understood that when the pressure of the hydraulic oil of the first oil port is greater than the pressure of the hydraulic oil of the second oil port, the first oil port is communicated with the second control valve through the first interface and the third interface, and when the pressure of the hydraulic oil of the second oil port is greater than the pressure of the hydraulic oil of the first oil port, the second oil port is communicated with the second control valve through the second interface and the third interface.

That is, by providing the shuttle valve, the spring chamber of each logic valve can be communicated with high-pressure oil when the second control valve is in the first working position, so that each logic valve can be kept in a cut-off state when the milling machine is in the forward or backward movement, and the anti-slip effect of the milling machine is further ensured.

In some embodiments, optionally, the control valve group includes a plurality of solenoid valves, each solenoid valve including a third communication port and a fourth communication port, the third communication port being in communication with the first manifold port, the fourth communication port being in communication with the first shunt port; wherein, under the condition that each electromagnetic valve is conducted, each first flow distributing and collecting valve is cut off; with each solenoid valve closed, each first current dividing and collecting valve is closed.

In this technical solution, it is defined that the control valve group includes a plurality of solenoid valves, specifically, the third communication port of each solenoid valve communicates with the first collecting port, and the fourth communication port of each solenoid valve communicates with the first dividing port.

Optionally, the plurality of electromagnetic valves includes a first electromagnetic valve, a second electromagnetic valve, a third electromagnetic valve, and a fourth electromagnetic valve, wherein the first electromagnetic valve is connected to the first manifold of one of the first current and flow valves and one of the first shunt ports of the first current and flow valves, and the second electromagnetic valve is connected to the first manifold of the first current and flow valve and the other first shunt port.

The third electromagnetic valve is connected with the first flow collecting port of the other first flow distributing and collecting valve and one of the first shunt ports of the first flow distributing and collecting valve, and the fourth electromagnetic valve is connected with the first flow collecting port of the first flow distributing and collecting valve and the other first shunt port.

Specifically, when each electromagnetic valve is cut off, each first flow distributing and collecting valve is conducted, and the working condition of straight running flow distributing and collecting is entered, and optionally, flow distributing is carried out in a forward mode, and flow collecting is carried out in a backward mode. Thereby the milling machine has the anti-skid function.

When each electromagnetic valve is conducted, each first flow distributing and collecting valve is cut off, and it can be understood that because the flow resistance of the electromagnetic valve is smaller than that of the first flow distributing and collecting valve, hydraulic oil pumped by the pump body is freely distributed to the plurality of electromagnetic valves when the electromagnetic valve is conducted, and then flows to the plurality of hydraulic driving pieces through the plurality of electromagnetic valves respectively, and does not flow to the first flow distributing and collecting valve, so that the free wheel working condition is realized.

The electromagnetic valves are controlled to be switched on or off, so that the switching between the forward and backward flow distribution and collection and the free wheel is realized, the control is simple and convenient, an external control oil source is not needed, and the production cost of a hydraulic driving system and a milling machine with the hydraulic driving system is reduced.

Optionally, the solenoid valve is a solenoid valve.

In some aspects, optionally, the pump body comprises a closed bidirectional variable pump; and/or each hydraulic drive includes a bi-directional variable motor.

In the technical scheme, the pump body is a closed bidirectional variable pump, and/or each hydraulic driving piece is a bidirectional variable motor, so that the forward and backward traveling functions of the milling machine are realized.

In some embodiments, optionally, the number of the first flow dividing and collecting valves is two, the hydraulic driving system further includes a second flow dividing and collecting valve, the second flow dividing and collecting valve is disposed between the pump body and the two first flow dividing and collecting valves, the second flow dividing and collecting valve has a second flow collecting port and two second flow dividing and collecting ports, the second flow dividing and collecting ports are communicated with the pump body, and the two second flow dividing and collecting ports are respectively communicated with the two first flow collecting ports.

In this solution, it is defined that the hydraulic drive system further comprises a second flow dividing and collecting valve, in particular, the second flow dividing and collecting valve is arranged between the pump body and the two first flow dividing and collecting valves, and the second flow collecting port of the second flow dividing and collecting valve communicates with the pump body, and the two second flow dividing and collecting ports of the second flow dividing and collecting valve communicate with the two first flow collecting ports, respectively, that is, the two first flow dividing and collecting valves communicate with the pump body through the second flow dividing and collecting valve.

Through setting up the second branch mass flow valve for when the reposition of redundant personnel, the hydraulic oil that distributes two first branch mass flow valves equals, consequently, need not to specify two first shunt ports of first branch mass flow valve respectively with two specific hydraulic drive spare intercommunication, also can ensure that each wheel has the same speed of traveling when straight line is traveling, be favorable to improving the antiskid effect of milling machine.

Wherein two specific hydraulic drives refer to two hydraulic drives driving two wheels located in a diagonal direction.

In some embodiments, optionally, the hydraulic driving system further includes a third control valve, and two ends of the third control valve are respectively connected to two second chokes of the second current dividing and collecting valve, so as to enable the two second chokes to be conducted under the condition that a pressure difference exists between two ends of the third control valve.

In the technical scheme, the hydraulic driving system is limited to further comprise a third control valve, specifically, the two second flow dividing and collecting valves are connected through the third control valve, when pressure difference is generated at two ends of the third control valve, the third control valve enables the two second flow dividing and collecting valves to be conducted, so that automatic flow compensation is achieved under the steering and flow dividing working condition of the milling machine, the hydraulic driving system is not prone to pressure holding, and the reliability of the hydraulic driving system is improved.

Optionally, the third control valve comprises a throttle valve.

According to a second aspect of the present invention, a milling machine is provided, which comprises a hydraulic driving system according to any of the above-mentioned aspects, so that all the advantageous technical effects of the hydraulic driving system are provided, and are not described in detail herein.

Further, the milling machine further comprises a machine body and a plurality of traveling devices, wherein the traveling devices are arranged on the machine body and are respectively connected with the hydraulic driving pieces.

The milling machine provided by the embodiment of the invention comprises a hydraulic driving system, a machine body and a plurality of running devices, and particularly, the running devices are respectively connected with the hydraulic driving pieces, so that the milling machine can realize a running function through the running devices under the driving of the hydraulic driving pieces.

Optionally, the plurality of running means comprises a plurality of wheels.

In addition, the milling machine provided by the technical scheme of the invention has the following additional technical characteristics:

In some embodiments, optionally, the plurality of driving devices includes a first driving device and a second driving device located in a diagonal direction, the plurality of hydraulic driving members includes a third hydraulic driving member and a fourth hydraulic driving member, the third hydraulic driving member is connected to the first driving device, and the fourth hydraulic driving member is connected to the second driving device; two first shunt ports of one first shunt and flow collecting valve are respectively communicated with a third hydraulic driving piece and a fourth hydraulic driving piece; or in the case of a hydraulic drive system comprising a second split-flow valve, two first split-flow ports of one first split-flow valve are in communication with any two of the plurality of hydraulic drives.

In this solution, it is defined that in case the hydraulic drive system comprises only at least two first flow dividing and collecting valves, the plurality of hydraulic drives comprises a third hydraulic drive and a fourth hydraulic drive, in particular the first running gear and the second running gear are arranged diagonally. Specifically, in the case where the first running gear is the left front wheel, the second running gear is the right rear wheel. Or in the case where the first running gear is the right front wheel, the second running gear is the left rear wheel. That is, the third hydraulic driver and the fourth hydraulic driver are two hydraulic drivers that drive two wheels located in the diagonal direction.

The two first shunt ports of the first shunt and flow collecting valve are respectively communicated with the third hydraulic driving piece and the fourth hydraulic driving piece, so that under the condition that a hydraulic driving system only has the two first shunt and flow collecting valves, the milling machine can stably and linearly run, deflection cannot occur, the anti-skid effect of the milling machine is improved, and the production cost of the milling machine is reduced.

It will be appreciated that if the two first split ports of one of the first split and flow valves are respectively connected to the two hydraulic driving members for driving the front left wheel and the rear left wheel, the two first split ports of the other first split and flow valve are respectively connected to the two hydraulic driving members for driving the front right wheel and the rear right wheel, and the flow rate of the hydraulic oil pumped by the pump body to the two first split and flow valves may be different, the milling machine is likely to deflect during straight running.

When the hydraulic drive system comprises a second flow dividing and collecting valve, the second flow dividing and collecting valve is arranged between the pump body and the two first flow dividing and collecting valves, and the second flow collecting port of the second flow dividing and collecting valve is communicated with the pump body, the two second flow dividing and collecting ports of the second flow dividing and collecting valve are respectively communicated with the two first flow collecting ports, that is, the two first flow dividing and collecting valves are communicated with the pump body through the second flow dividing and collecting valve.

Through setting up the second branch mass flow valve for when the reposition of redundant personnel, the hydraulic oil that distributes two first branch mass flow valves equals, consequently, need not to specify two first shunt ports of first branch mass flow valve respectively with two diagonal hydraulic drive spare intercommunication, also can ensure that each wheel has the same speed of traveling when traveling in a straight line, be favorable to improving the antiskid effect of milling machine.

Additional aspects and advantages of the invention will be set forth in part in the description which follows, and in part will be obvious from the description, or may be learned by practice of the invention.

Drawings

The foregoing and/or additional aspects and advantages of the invention will become apparent and may be better understood from the following description of embodiments taken in conjunction with the accompanying drawings in which:

FIG. 1 illustrates one of the structural schematic diagrams of a hydraulic drive system according to one embodiment of the present invention;

FIG. 2 shows a second schematic diagram of the hydraulic drive system according to one embodiment of the invention;

FIG. 3 illustrates a third schematic configuration of a hydraulic drive system according to one embodiment of the present invention;

FIG. 4 shows a fourth schematic diagram of the hydraulic drive system according to one embodiment of the invention;

fig. 5 shows a schematic structural view of a milling machine according to an embodiment of the present invention.

The correspondence between the reference numerals and the component names in fig. 1 to 5 is:

100 hydraulic drive systems, 110 pump bodies, 111 first hydraulic ports, 112 second hydraulic ports, 120 hydraulic drive systems, 121 first hydraulic drive systems, 122 second hydraulic drive systems, 123 third hydraulic drive systems, 124 fourth hydraulic drive systems, 130 first split and flow valves, 131 first fluid collecting ports, 132 first split ports, 140 first control valves, 141 throttles, 150 control valves, 151 logic valves, 152 second control valves, 153 control ports, 154 shuttle valves, 155 first ports, 156 second ports, 157 third ports, 158 solenoid valves, 160 oil tanks, 170 second split and flow valves, 171 second fluid collecting ports, 172 second split ports, 180 third control valves, 200 milling machines, 210 machine bodies, 220 running devices, 221 first running devices, 222 second running devices, 230 first communication ports, 240 second communication ports, 250 third communication ports, 260 fourth communication ports.

Detailed Description

In order that the above-recited objects, features and advantages of the present application will be more clearly understood, a more particular description of the application will be rendered by reference to the appended drawings and appended detailed description. It should be noted that, without conflict, the embodiments of the present application and features in the embodiments may be combined with each other.

In the following description, numerous specific details are set forth in order to provide a thorough understanding of the present invention, but the present invention may be practiced otherwise than as described herein, and therefore the scope of the present invention is not limited to the specific embodiments disclosed below.

A hydraulic drive system 100 and a milling machine 200 provided in accordance with some embodiments of the present invention are described below with reference to fig. 1-5.

In one embodiment according to the present application, as shown in fig. 1 and 2, a hydraulic drive system 100 is proposed, the hydraulic drive system 100 comprising: a pump body 110 and a plurality of hydraulic drives 120; at least two first flow dividing and collecting valves 130, each first flow dividing and collecting valve 130 having a first flow dividing and collecting port 131 and two first flow dividing and collecting ports 132, each first flow dividing and collecting port 131 communicating with the pump body 110, each first flow dividing and collecting port 132 communicating with one hydraulic driving member 120; the first control valve 140, the two first split ports 132 of at least one first split/flow valve 130 are connected to both ends of the first control valve 140, respectively, and the first control valve 140 can make the two first split ports 132 of the first split/flow valve 130 conductive when a pressure difference exists between both ends of the first control valve 140.

The hydraulic driving system 100 provided in the embodiment of the invention includes a pump body 110, a plurality of hydraulic driving members 120, at least two first flow dividing and collecting valves 130 and a first control valve 140, specifically, each first flow dividing and collecting valve 130 has one first flow collecting port 131 and two first flow dividing and collecting ports 132, that is, each first flow dividing and collecting valve 130 is a two-in-one equivalent flow dividing and collecting valve.

Each first manifold 131 communicates with the pump body 110, and each first split 132 communicates with one hydraulic driver 120, that is, at least two first split-manifold valves 130 are located between the pump body 110 and the plurality of hydraulic drivers 120. Specifically, when the milling machine 200 with the hydraulic driving system 100 advances, hydraulic oil pumped by the pump body 110 enters the first collecting port 131 of each first flow dividing and collecting valve 130 respectively, and after equal flow dividing, the hydraulic oil enters each hydraulic driving member 120 respectively, so as to realize the traveling driving of the milling machine 200. I.e. forward split drive. Alternatively, a reverse split drive, i.e., an equal split by at least two first split and collector valves 130 when milling machine 200 is reversing, is also possible.

When the milling machine 200 retreats, the hydraulic oil pumped by the pump body 110 flows to the first split ports 132 through the hydraulic driving members 120, and flows back to the pump body 110 after being collected through the first collecting ports 131, i.e. retreated and collected. Alternatively, a forward flow collecting drive, i.e. a flow collecting by at least two first flow distributing and collecting valves 130 when the milling machine 200 is forward, may also be performed. The setting can be specifically performed according to actual needs.

The equal flow distribution of the hydraulic oil is realized through at least two equal flow distribution and collection valves which are divided into two parts, and the anti-skid effect can be achieved when the milling machine 200 walks. In addition, compared with the prior art that a quarter equivalent flow dividing and collecting valve is utilized, the internal structure of the flow dividing and collecting valve is simplified, the manufacturing difficulty of the flow dividing and collecting valve is reduced, the production cost of the hydraulic driving system 100 is reduced on the premise of ensuring the anti-skid effect, and the production cost of the milling machine 200 with the hydraulic driving system 100 is further reduced.

In addition, the use of one pump body 110 to realize the circulation driving of hydraulic oil is beneficial to simplifying the structure of the hydraulic driving system 100 and further reducing the production cost of the hydraulic driving system 100 compared with the use of double pumps for driving in the related art. Moreover, compared with the prior art in which motors are controlled by program differentiation, the control is simple and convenient, and the structure such as a rotation speed sensor is not required to be additionally arranged, so that the production cost of the milling machine 200 with the hydraulic driving system 100 is greatly reduced.

It will be appreciated that the travel speeds of the left and right front wheels differ when the milling machine 200 is turned, such that the rotational speeds of the two hydraulic drives 120 respectively associated with the left and right front wheels differ. The traveling speeds of the left front wheel and the right rear wheel are also different so that the rotational speeds of the two hydraulic actuators 120 respectively connected to the left front wheel and the right rear wheel are different. That is, when the milling machine 200 turns, the flow rates required for the two hydraulic driving units 120 respectively connected to the two wheels having different traveling speeds are different, resulting in a situation that the system is prone to pressure holding.

The two first split ports 132 of the at least one first split and flow valve 130 are connected through the first control valve 140, and when the two ends of the first control valve 140 have a pressure difference, the first control valve 140 enables the two first split ports 132 of the first split and flow valve 130 to be conducted, so that automatic flow compensation is realized under the working condition that the milling machine 200 turns to diversity flow, the hydraulic driving system 100 is not easy to generate pressure holding, and the reliability of the hydraulic driving system 100 is improved.

It will be appreciated that, when the milling machine 200 is turned, a pressure differential is created across the first control valve 140 because the flow rates required by the two hydraulic drives 120 respectively associated with the two wheels at different speeds of travel are different.

Optionally, each hydraulic drive 120 is a hydraulic motor.

As shown in fig. 1 and 2, in some embodiments, the first control valve 140 is optionally a throttle valve 141.

In this embodiment, the first control valve 140 is defined as a throttle valve 141, it is understood that when there is a pressure difference between two ends of the throttle valve 141, the throttle valve 141 is turned on, so that two first split ports 132 of the first split-flow collecting valve 130 are turned on, and automatic flow compensation under the steering working condition of the milling machine 200 is achieved, and the system is prevented from being pressurized.

In addition, since the through-flow cross-sectional area of the throttle 141 is small, even if the throttle 141 is turned on, the flow rate of the hydraulic oil flowing through the throttle 141 is small, so that the situation that the traveling failure of the milling machine 200 occurs due to the fact that most of the flow rate on one side flows to the other side when the milling machine 200 is turned is prevented, and the stability and the reliability of the traveling process of the milling machine 200 are ensured.

As shown in fig. 1, in some embodiments, optionally, the plurality of hydraulic drives 120 includes at least a first hydraulic drive 121 and a second hydraulic drive 122, the first hydraulic drive 121 and the second hydraulic drive 122 being capable of different rotational speeds; wherein the first hydraulic driving member 121 and the second hydraulic driving member 122 are respectively communicated with two first split ports 132 of one first split-flow collecting valve 130. Alternatively, the first hydraulic drive 121 and the second hydraulic drive 122 are each coupled to two wheels of the milling machine 200.

It will be appreciated that when milling machine 200 is turned, the two wheels respectively associated with first hydraulic drive member 121 and second hydraulic drive member 122 have different travel speeds such that first hydraulic drive member 121 and second hydraulic drive member 122 have different rotational speeds, i.e., the flow rates required by first hydraulic drive member 121 and second hydraulic drive member 122 are different.

Alternatively, the first and second hydraulic driving members 121 and 122 are connected to the left and right front wheels, respectively. Or the first and second hydraulic driving members 121 and 122 are respectively connected to the left and right front wheels.

The two first split ports 132 of the first split-flow valve 130 are respectively communicated with the first hydraulic driver 121 and the second hydraulic driver 122, which can have different rotational speeds. Because the two first split ports 132 are connected through the first control valve 140, when the milling machine 200 turns, the two ends of the first control valve 140 generate pressure difference, so that the two first split ports 132 are conducted, and automatic flow compensation is realized under the working condition of turning diversity flow of the milling machine 200, so that the hydraulic drive system 100 is not easy to generate pressure holding, and the reliability of the hydraulic drive system 100 is improved.

As shown in fig. 1,2,3, and 4, in some embodiments, optionally, the hydraulic drive system 100 further includes a control valve block 150, the control valve block 150 being connected to the first manifold 131 and the two first branches 132 of each first branch manifold valve 130; wherein, with the control valve block 150 turned on, each first current diverting and collecting valve 130 is turned off; with the control valve block 150 closed, each first current diverting and collecting valve 130 is turned on.

In this embodiment, it is defined that the hydraulic drive system 100 further comprises a control valve group 150, in particular, the control valve group 150 is connected to the first manifold 131 of each first manifold valve 130 and to the two first shunt ports 132 of each first manifold valve 130.

When the control valve block 150 is turned on, each of the first current diverting and collecting valves 130 is turned off, and one of the working conditions of the milling machine 200, optionally, the freewheel working condition, may be realized. When the control valve group 150 is turned off, each first current and flow distributing valve 130 is turned on, and equal current and flow distribution are performed when the milling machine 200 runs, so that an anti-slip effect can be achieved, and another working condition of the milling machine 200 can be realized, and optionally, a straight running current and flow distributing working condition can be realized.

That is, by turning on or off the control valve block 150, the switching of the milling machine 200 under various working conditions can be realized, and the control is simple and convenient, and the production cost of the hydraulic driving system 100 is reduced without an external control oil source.

As shown in fig. 1 and 3, in some embodiments, optionally, the control valve block 150 includes a plurality of logic valves 151 and a second control valve 152, wherein each logic valve 151 includes a first communication port 230, a second communication port 240, and a control port 153, the first communication port 230 communicates with the first manifold port 131, the second communication port 240 communicates with the first bypass port 132, the second control valve 152 is connected to each control port 153 and the pump body 110, and the second control valve 152 has at least a first operating position and a second operating position; when the second control valve 152 is in the first working position, the pump body 110 is connected to each control port 153 through the second control valve 152, each logic valve 151 is closed, and each first current distribution and collection valve 130 is connected; with the second control valve 152 in the second operating position, each control port 153 communicates with the tank 160 through the second control valve 152, each logic valve 151 is on, and each first split and collector valve 130 is off.

In this embodiment, it is defined that the control valve group 150 includes a plurality of logic valves 151 and a second control valve 152, and specifically, each logic valve 151 includes a first communication port 230, a second communication port 240, and a control port 153, the first communication port 230 communicates with the first collecting port 131, and the second communication port 240 communicates with the first dividing port 132.

Optionally, the plurality of logic valves 151 includes a first logic valve connected to the first collecting port 131 of one of the first split-flow collecting valves 130 and one of the first dividing and collecting ports 132 of the first split-flow collecting valve 130, a second logic valve connected to the first collecting port 131 of the first split-flow collecting valve 130 and the other first dividing and collecting port 132, a third logic valve, and a fourth logic valve.

The third logic valve is connected to the first collecting port 131 of the other first collecting and distributing valve 130 and one of the first dividing ports 132 of the first collecting and distributing valve 130, and the fourth logic valve is connected to the first collecting port 131 of the first collecting and distributing valve 130 and the other first dividing port 132.

Each logic valve 151 has a control port 153, optionally, the control port 153 of each logic valve 151 communicates with the spring chamber of that logic valve 151.

A second control valve 152 is connected to each control port 153 and the pump body 110. Specifically, the second control valve 152 has at least a first working position and a second working position, when the second control valve 152 is in the first working position, the pump body 110 is communicated with the control port 153 of each logic valve 151 through the second control valve 152, high-pressure oil is communicated with the spring cavity of each logic valve 151, each logic valve 151 is blocked due to the area difference, each first current dividing and collecting valve 130 is communicated, and a straight running current dividing and collecting working condition is entered, and optionally, current is divided forward and collected backward. Thereby providing the milling machine 200 with an anti-slip function.

When the second control valve 152 is in the second working position, each control port 153 is communicated with the oil tank 160 through the second control valve 152, that is, the spring cavity of each logic valve 151 is communicated with the oil tank 160 for pressure relief, so that each logic valve 151 is conducted. Since the flow resistance of the logic valve 151 is smaller than that of the first flow dividing and collecting valve 130, when the logic valve 151 is turned on, hydraulic oil pumped by the pump body 110 is freely distributed to the plurality of logic valves 151, and then flows to the plurality of hydraulic driving pieces 120 through the plurality of logic valves 151, respectively, without flowing to the first flow dividing and collecting valve 130, thereby realizing a free wheel working condition.

By controlling the second control valve 152 to be in different working positions, the logic valve 151 can be turned on or off, so that the forward and backward flow distribution and collection and the free wheel can be switched, the control is simple and convenient, an external control oil source is not needed, and the production cost of the hydraulic driving system 100 and the milling machine 200 with the hydraulic driving system 100 can be reduced.

Alternatively, the second control valve 152 is a two-position four-way solenoid valve.

As shown in fig. 1 and 3, in some embodiments, optionally, the pump body 110 includes a first port 111 and a second port 112, the first port 111 communicates with each first manifold 131, the second port 112 communicates with each hydraulic drive 120, the control valve block 150 further includes a shuttle valve 154, the shuttle valve 154 has a first port 155, a second port 156, and a third port 157, the first port 155 communicates with the first port 111, the second port 156 communicates with the second port 112, and the third port 157 communicates with the second control valve 152.

In this embodiment, the control valve block 150 is defined to further include a shuttle valve 154, and specifically, a first port 155 and a second port 156 of the shuttle valve 154 communicate with the first port 111 and the second port 112 of the pump body 110, respectively. It is understood that when the pressure of the hydraulic oil of the first port 111 is greater than the pressure of the hydraulic oil of the second port 112, the first port 111 communicates with the second control valve 152 through the first port 155 and the third port 157, and when the pressure of the hydraulic oil of the second port 112 is greater than the pressure of the hydraulic oil of the first port 111, the second port 112 communicates with the second control valve 152 through the second port 156 and the third port 157.

That is, by providing the shuttle valve 154, the spring chamber of each logic valve 151 can be communicated with high-pressure oil when the second control valve 152 is in the first working position, thereby ensuring that each logic valve 151 can be maintained in a cut-off state when the milling machine 200 is advanced or retreated, and further ensuring the anti-slip effect of the milling machine 200.

As shown in fig. 2 and 4, in some embodiments, optionally, the control valve block 150 includes a plurality of solenoid valves 158, each solenoid valve 158 including a third communication port 250 and a fourth communication port 260, the third communication port 250 communicating with the first collection port 131, the fourth communication port 260 communicating with the first diversion port 132; wherein, with each solenoid valve 158 turned on, each first current and current valve 130 is turned off; with each solenoid valve 158 closed, each first current and flow valve 130 is open.

In this embodiment, the control valve bank 150 is defined to include a plurality of solenoid valves 158, and specifically, a third communication port 250 of each solenoid valve 158 communicates with the first manifold port 131 and a fourth communication port 260 of each solenoid valve 158 communicates with the first bypass port 132.

Optionally, the plurality of solenoid valves 158 includes a first solenoid valve connected to the first manifold 131 of one of the first split-flow collecting valves 130 and one of the first split-flow ports 132 of the first split-flow collecting valve 130, a second solenoid valve connected to the first manifold 131 of the first split-flow collecting valve 130 and the other first split-flow port 132, a third solenoid valve, and a fourth solenoid valve.

The third solenoid valve is connected to the first collecting port 131 of the other first collecting and distributing valve 130 and one of the first dividing ports 132 of the first collecting and distributing valve 130, and the fourth solenoid valve is connected to the first collecting port 131 of the first collecting and distributing valve 130 and the other first dividing port 132.

Specifically, when each solenoid valve 158 is closed, each first manifold valve 130 is open, entering a straight travel manifold condition, optionally forward manifold, reverse manifold. Thereby providing the milling machine 200 with an anti-slip function.

When each of the solenoid valves 158 is turned on, each of the first current and flow valves 130 is turned off, and it can be understood that since the flow resistance of the solenoid valve 158 is smaller than that of the first current and flow valve 130, when the solenoid valve 158 is turned on, hydraulic oil pumped by the pump body 110 is freely distributed to the plurality of solenoid valves 158, and then flows to the plurality of hydraulic driving members 120 through the plurality of solenoid valves 158, respectively, without flowing to the first current and flow valve 130, thereby realizing a free-wheel operation.

By controlling the switching on or off of the plurality of electromagnetic valves 158, the switching between the forward and backward flow distribution and collection and the freewheel is realized, the control is simple and convenient, an external control oil source is not needed, and the production cost of the hydraulic drive system 100 and the milling machine 200 with the hydraulic drive system 100 is reduced.

Alternatively, solenoid valve 158 is a solenoid valve.

As shown in fig. 1,2,3, and 4, in some embodiments, the pump body 110 optionally includes a closed bidirectional variable displacement pump; and/or each hydraulic drive 120 includes a bi-directional variable motor.

In this embodiment, the pump body 110 is a closed bi-directional variable displacement pump and/or each hydraulic drive 120 is a bi-directional variable displacement motor to perform the walk function of the milling machine 200 both forward and reverse.

As shown in fig. 3 and 4, in some embodiments, optionally, the number of the first flow dividing and collecting valves 130 is two, and the hydraulic driving system 100 further includes a second flow dividing and collecting valve 170, where the second flow dividing and collecting valve 170 is disposed between the pump body 110 and the two first flow dividing and collecting valves 130, and the second flow dividing and collecting valve 170 has a second flow dividing and collecting port 171 and two second flow dividing and collecting ports 172, where the second flow dividing and collecting port 171 communicates with the pump body 110, and the two second flow dividing and collecting ports 172 communicate with the two first flow dividing and collecting ports 131, respectively.

In this embodiment, it is defined that the hydraulic drive system 100 further includes a second flow dividing and collecting valve 170, specifically, the second flow dividing and collecting valve 170 is disposed between the pump body 110 and the two first flow dividing and collecting valves 130, and the second flow collecting port 171 of the second flow dividing and collecting valve 170 communicates with the pump body 110, and the two second flow dividing and collecting ports 172 of the second flow dividing and collecting valve 170 communicate with the two first flow collecting ports 131, respectively, that is, the two first flow dividing and collecting valves 130 communicate with the pump body 110 through the second flow dividing and collecting valve 170.

By providing the second flow dividing and collecting valve 170, the hydraulic oil distributed to the two first flow dividing and collecting valves 130 is equal during the flow dividing, so that it is not necessary to specify that the two first flow dividing and collecting ports 132 of the first flow dividing and collecting valve 130 are respectively communicated with the two specific hydraulic driving members 120, it is also possible to ensure that each wheel has the same running speed during the straight running, and it is advantageous to improve the anti-slip effect of the milling machine 200.

Wherein two specific hydraulic drives 120 refer to two hydraulic drives 120 driving two wheels located in a diagonal direction.

As shown in fig. 3 and 4, in some embodiments, the hydraulic drive system 100 optionally further includes a third control valve 180, where two ends of the third control valve 180 are respectively connected to two second chokes 172 of the second current sharing valve 170, so as to make the two second chokes 172 conductive in the case that there is a pressure difference across the third control valve 180.

In this embodiment, the hydraulic driving system 100 is further defined to include a third control valve 180, specifically, the two second chokes 172 of the second shunt current collecting valve 170 are connected through the third control valve 180, when a pressure difference is generated at two ends of the third control valve 180, the third control valve 180 makes the two second chokes 172 conductive, so that automatic flow compensation is achieved under the steering diversity current working condition of the milling machine 200, so that the hydraulic driving system 100 is not prone to pressure holding, and reliability of the hydraulic driving system 100 is improved.

Optionally, the third control valve 180 comprises a throttle valve.

According to a second aspect of the present invention, a milling machine 200 is provided, which includes the hydraulic driving system 100 according to any of the above embodiments, so that all the advantages of the hydraulic driving system 100 are provided, and are not described herein.

As shown in fig. 5, the milling machine 200 further includes a machine body 210 and a plurality of traveling devices 220, wherein the traveling devices 220 are disposed on the machine body 210 and are respectively connected to the hydraulic driving units 120.

The milling machine 200 provided by the embodiment of the invention includes a hydraulic driving system 100, a machine body 210 and a plurality of traveling devices 220, and specifically, the plurality of traveling devices 220 are respectively connected with the plurality of hydraulic driving pieces 120, so that the milling machine 200 can realize a traveling function through the plurality of traveling devices 220 under the driving of the plurality of hydraulic driving pieces 120.

Optionally, the plurality of running gears 220 comprises a plurality of wheels.

As shown in fig. 5, in some embodiments, optionally, the plurality of driving devices 220 includes a first driving device 221 and a second driving device 222 positioned in a diagonal direction, the plurality of hydraulic driving members 120 includes a third hydraulic driving member 123 and a fourth hydraulic driving member 124, the third hydraulic driving member 123 is connected to the first driving device 221, and the fourth hydraulic driving member 124 is connected to the second driving device 222; two first split ports 132 of one first split-flow collecting valve 130 are respectively communicated with the third hydraulic driving member 123 and the fourth hydraulic driving member 124; or where the hydraulic drive system 100 includes a second split-flow combining valve 170, two first split-flow ports 132 of one first split-flow combining valve 130 communicate with any two hydraulic drives 120 of the plurality of hydraulic drives 120.

In this embodiment, it is defined that in the case where the hydraulic drive system 100 includes only at least two first flow dividing and collecting valves 130, the plurality of hydraulic drives 120 includes the third hydraulic drive 123 and the fourth hydraulic drive 124, and specifically, the first traveling device 221 and the second traveling device 222 are arranged in a diagonal direction. Specifically, in the case where the first traveling device 221 is the left front wheel, the second traveling device 222 is the right rear wheel. Or in the case where the first traveling device 221 is a right front wheel, the second traveling device 222 is a left rear wheel. That is, the third hydraulic driver 123 and the fourth hydraulic driver 124 are two hydraulic drivers 120 that drive two wheels located in the diagonal direction.

The two first split ports 132 of the first split and combined valve 130 are respectively communicated with the third hydraulic driving part 123 and the fourth hydraulic driving part 124, so that the milling machine 200 can be ensured to stably run in a straight line without deflection even in the case that the hydraulic driving system 100 only has the two first split and combined valves 130, thereby being beneficial to improving the anti-skid effect of the milling machine 200 and reducing the production cost of the milling machine 200.

It will be appreciated that if the two first split ports 132 of one of the first split and flow valves 130 are respectively connected to the two hydraulic driving members 120 for driving the front left wheel and the rear left wheel, the two first split ports 132 of the other first split and flow valve 130 are respectively connected to the two hydraulic driving members 120 for driving the front right wheel and the rear right wheel, the flow rate of the hydraulic oil pumped by the pump body 110 to the two first split and flow valve 130 may be different, which may easily cause the milling machine 200 to deflect during straight running.

When the hydraulic drive system 100 includes the second split and collector valve 170, since the second split and collector valve 170 is disposed between the pump body 110 and the two first split and collector valves 130, and the second fluid collecting port 171 of the second split and collector valve 170 communicates with the pump body 110, the two second fluid collecting ports 172 of the second split and collector valve 170 communicate with the two first fluid collecting ports 131, respectively, that is, the two first split and collector valves 130 communicate with the pump body 110 through the second split and collector valve 170.

By providing the second flow dividing and collecting valve 170, the hydraulic oil distributed to the two first flow dividing and collecting valves 130 is equal during the flow dividing, so that it is not necessary to specify that the two first flow dividing and collecting ports 132 of the first flow dividing and collecting valve 130 are respectively communicated with the two diagonally-oriented hydraulic driving members 120, and it is also possible to ensure that each wheel has the same running speed during the straight running, which is advantageous for improving the anti-slip effect of the milling machine 200.

In one particular embodiment, as shown in FIG. 1, a hydraulic drive system 100 includes a drive unit: a traveling pump (pump body 110); an execution unit: a left front travel motor (hydraulic driver 120), a right rear travel motor (hydraulic driver 120), a right front travel motor (hydraulic driver 120), a left rear travel motor (hydraulic driver 120); and a control unit: the diversity flow valve assembly includes a first logic valve, a second logic valve, a third logic valve, a fourth logic valve, two first diversity flow valves 130, two throttle valves 141, an anti-slip control valve (second control valve 152), and a shuttle valve 154.

The first logic valve and the second logic valve inlet (first communication port 230) are respectively connected with the inlet (first collecting port 131) of the first flow dividing and collecting valve 130, the first logic valve and the second logic valve outlet (second communication port 240) are respectively connected with the two outlets (first dividing and collecting port 132) of the first flow dividing and collecting valve, and the two outlets of the first flow dividing and collecting valve 130 are connected through the throttle valve 141.

The third logic valve and the fourth logic valve inlet (first communication port 230) are respectively connected with the inlet (first collecting port 131) of the second shunt collecting valve (the other first shunt collecting valve 130), the third logic valve and the fourth logic valve outlet (second communication port 240) are respectively connected with the two outlets (first dividing port 132) of the second shunt collecting valve (the other first shunt collecting valve 130), and the two outlets (first dividing port 132) of the second shunt collecting valve (the other first shunt collecting valve 130) are connected through the other throttle valve 141.

The inlets (first flow collecting ports 131) of the two first flow dividing and collecting valves 130 are connected with the outlets (first oil ports 111) of the traveling pump (the pump body 110), the two outlets (first flow dividing and collecting ports 132) of the first flow dividing and collecting valves 130 are respectively connected with the inlets of the front left traveling motor (the third hydraulic driving piece 123) and the rear right traveling motor (the fourth hydraulic driving piece 124), and the two outlets (first flow dividing and collecting ports 132) of the second flow dividing and collecting valve (the other first flow dividing and collecting valve 130) are respectively connected with the inlets of the front right traveling motor and the rear left traveling motor. The left front walking motor, the right rear walking motor, the right front walking motor and the left rear walking motor outlet are respectively connected with the inlet (the second oil port 112) of the walking pump (the pump body 110).

Both ends (a first port 155 and a second port 156) of the shuttle valve 154 are connected to an a port (a first port 111) and a B port (a second port 112) of the traveling pump, respectively, and a control port (a third port 157) is connected to a P port of the antiskid control valve (a second control valve). And the port B of the anti-slip control valve is respectively connected with spring cavities of the first logic valve, the second logic valve, the third logic valve and the fourth logic valve. The T port of the antiskid control valve is connected to the oil tank 160.

In this embodiment, the running pump (pump body 110) is a closed bidirectional variable pump, the running motor (hydraulic driving member 120) is a bidirectional variable motor, and the diversity flow valve assembly is arranged between the running pump and the running motor, in particular, the diversity flow valve assembly is positioned at a high-pressure outlet of the running pump, so that the functions of forward flow distribution and free wheel of the equipment and the flow collection and free wheel of the backward flow can be realized.

Specifically, under the freewheel condition, the antiskid control valve (the second control valve 152) is not electrified, and works in the right position (the second working position), the spring cavity pressures of the first logic valve, the second logic valve, the third logic valve and the fourth logic valve are communicated with the oil tank 160, and the four logic valves 151 are in a normally open state. The traveling pump is communicated with the four traveling motors through the four logic valves, and the outlet flow of the traveling pump is freely distributed to the four traveling motors, so that free wheels in advancing and retreating are realized.

The straight running current-dividing and current-collecting working condition is that the anti-skid control valve (the second control valve 152) is electrified and works at the left position (the first working position), the shuttle valve 154 introduces high-pressure oil of the running pump (the pump body 110) into the oil source serving as the anti-skid control valve, and the spring cavities of the first logic valve, the second logic valve, the third logic valve and the fourth logic valve are respectively conducted, so that the logic valve 151 is always in a cut-off state due to the area difference. Advancing: the flow of the traveling pump outlet is equally split to a left front traveling motor, a right rear traveling motor, a right front traveling motor and a left rear traveling motor through the two first split flow valves 130 respectively, so that the forward split function is realized. And (3) retreating: the outlet flow of the left front walking motor, the right rear walking motor, the right front walking motor and the left rear walking motor is subjected to equal flow collection through the two first flow distribution and collection valves 130 and then reaches the inlet of a walking pump (pump body 110), so that the backward flow and flow collection function is realized.

On the basis of realizing equal forward flow distribution and equal backward flow collection, the steering running flow distribution and collection working conditions realize the compensation of flow when the left front running motor and the right rear running motor steer through a first throttle valve (a throttle valve 141), and the compensation of flow when the right front running motor and the left rear running motor steer through a second throttle valve (a throttle valve 141), so that the system is prevented from being pressed.

In another specific embodiment, as shown in fig. 2, the hydraulic drive system 100 includes a drive unit: a traveling pump (pump body 110); an execution unit: a left front travel motor (hydraulic driver 120), a right rear travel motor (hydraulic driver 120), a left rear travel motor (hydraulic driver 120); and a control unit: the diversity flow valve assembly comprises a first electromagnetic ball valve (electromagnetic valve 158), a second electromagnetic ball valve (electromagnetic valve 158), a third electromagnetic ball valve (electromagnetic valve 158), a fourth electromagnetic ball valve (electromagnetic valve 158), two first flow dividing and collecting valves 130 and two throttle valves 141.

The first electromagnetic ball valve and the second electromagnetic ball valve are respectively connected with the inlet (the first collecting port 131) of the first flow dividing and collecting valve 130 (the third communicating port 250), the first electromagnetic ball valve and the second electromagnetic ball valve are respectively connected with the two outlets (the first dividing and collecting port 132) of the first flow dividing and collecting valve 130 (the fourth communicating port 260), and the two outlets of the first flow dividing and collecting valve 130 are connected through the throttle valve 141.

The third electromagnetic ball valve and the fourth electromagnetic ball valve inlet (third communication port 250) are respectively connected with the inlet (first collecting port 131) of the second shunt collecting valve (another first shunt collecting valve 130), the third electromagnetic ball valve and the fourth electromagnetic ball valve outlet (fourth communication port 260) are respectively connected with the two outlets (first dividing port 132) of the second shunt collecting valve (another first shunt collecting valve 130), and the two outlets (first dividing port 132) of the second shunt collecting valve (another first shunt collecting valve 130) are connected through the throttle valve 141.

The inlets (first flow collecting ports 131) of the two first flow dividing and collecting valves 130 are connected with the outlets (first oil ports 111) of the traveling pump (the pump body 110), the two outlets (first flow dividing and collecting ports 132) of the first flow dividing and collecting valves 130 are respectively connected with the inlets of the front left traveling motor (the third hydraulic driving piece 123) and the rear right traveling motor (the fourth hydraulic driving piece 124), and the two outlets (first flow dividing and collecting ports 132) of the second flow dividing and collecting valve (the other first flow dividing and collecting valve 130) are respectively connected with the inlets of the front right traveling motor and the rear left traveling motor. The left front walking motor, the right rear walking motor and the left rear walking motor outlet are respectively connected with the inlet (the second oil port 112) of the walking pump (the pump body 110).

Under the working condition of the free wheel, the first electromagnetic ball valve (electromagnetic valve 158), the second electromagnetic ball valve (electromagnetic valve 158), the third electromagnetic ball valve (electromagnetic valve 158) and the fourth electromagnetic ball valve (electromagnetic valve 158) are not electrified (conducted), the traveling pump is communicated with four traveling motors through the four electromagnetic ball valves, and the outlet flow of the traveling pump is freely distributed to the four traveling motors, so that the free wheel during advancing and retreating is realized.

And under the working conditions of straight running current distribution and collection, the first electromagnetic ball valve (electromagnetic valve 158), the second electromagnetic ball valve (electromagnetic valve 158), the third electromagnetic ball valve (electromagnetic valve 158) and the fourth electromagnetic ball valve (electromagnetic valve 158) are powered on (cut off) simultaneously, and the electromagnetic ball valves work in a right cut-off state. Advancing: the flow of the traveling pump outlet is equally split to a left front traveling motor, a right rear traveling motor and a left rear traveling motor through the two first split flow valves 130 respectively, so that the forward split function is realized. And (3) retreating: the outlet flow of the left front walking motor, the right rear walking motor and the left rear walking motor is subjected to equal flow collection through the two first flow distribution and collection valves 130 and then reaches the inlet of a walking pump (pump body 110) to realize the backward flow and flow collection function.

In yet another specific embodiment, as shown in fig. 3, three split equal split valves (two first split valves 130 and second split valves 170) are used, and the first split valve (second split valve 170) outlet (second split valve 172) is the inlet (first split port 131) of the second and third split valves (two first split valves 130), respectively, so that the four-way oil path from the outlets (first split ports 132) of the second and third split valves can be freely connected to four travel motors (hydraulic actuators 120) without the need to specify that the same split valve (first split valve 130) must be connected to two motors (third hydraulic actuator 123 and fourth hydraulic actuator 124) in the diagonal direction.

In yet another specific embodiment, as shown in fig. 4, three split equal split valves (two first split valves 130 and second split valves 170) are used, and the first split valve (second split valve 170) outlet (second split valve 172) is the inlet (first split port 131) of the second split valve and the third split valve (two first split valves 130), respectively, so that four paths of oil from the outlets (first split ports 132) of the second split valve and the third split valve can be freely connected to four travel motors (hydraulic driving members 120) without the need to specify that the same split valve (first split valve 130) must be connected to two motors (third hydraulic driving member 123 and fourth hydraulic driving member 124) in the diagonal direction.

In the description of the present specification, the terms "connected," "mounted," "secured," and the like are to be construed broadly, and for example, "connected" may be a fixed connection, a removable connection, or an integral connection; can be directly connected or indirectly connected through an intermediate medium. The specific meaning of the above terms in the present invention can be understood by those of ordinary skill in the art according to the specific circumstances.

In the description of the present specification, the terms "one embodiment," "some embodiments," "particular embodiments," and the like, mean that a particular feature, structure, material, or characteristic described in connection with the embodiment or example is included in at least one embodiment or example of the present invention. In this specification, schematic representations of the above terms do not necessarily refer to the same embodiment or example. Furthermore, the particular features, structures, materials, or characteristics described may be combined in any suitable manner in any one or more embodiments or examples.

The above is only a preferred embodiment of the present invention, and is not intended to limit the present invention, but various modifications and variations can be made to the present invention by those skilled in the art. Any modification, equivalent replacement, improvement, etc. made within the spirit and principle of the present invention should be included in the protection scope of the present invention.

Claims

1. A hydraulic drive system, comprising:

A pump body and a plurality of hydraulic drives;

at least two first flow dividing and collecting valves, each of which is provided with a first flow collecting port and two first flow dividing ports, each of which is communicated with the pump body, and each of which is communicated with one of the hydraulic driving parts;

the first control valve is used for enabling the two first shunt ports of the first shunt and current collecting valve to be conducted under the condition that pressure differences exist at the two ends of the first control valve.

2. The hydraulic drive system of claim 1, wherein the first control valve is a throttle valve.

3. The hydraulic drive system according to claim 1 or 2, characterized by further comprising:

the control valve group is connected with the first flow collecting port and the two first flow dividing ports of each first flow dividing and collecting valve;

Under the condition that the control valve group is conducted, each first flow distributing and collecting valve is cut off; and under the condition that the control valve group is cut off, each first flow distributing and collecting valve is conducted.

4. A hydraulic drive system according to claim 3, wherein the control valve block comprises:

a plurality of logic valves, each logic valve comprising a first communication port, a second communication port and a control port, the first communication port being in communication with the first manifold port, the second communication port being in communication with the first shunt port;

The second control valve is connected with each control port and the pump body and is provided with at least a first working position and a second working position;

when the second control valve is in the first working position, the pump body is communicated with each control port through the second control valve, each logic valve is closed, and each first flow distributing and collecting valve is communicated;

And under the condition that the second control valve is positioned at the second working position, each control port is communicated with an oil tank through the second control valve, each logic valve is connected, and each first flow distributing and collecting valve is disconnected.

5. The hydraulic drive system of claim 4 wherein the pump body includes a first port in communication with each of the first manifold ports and a second port in communication with each of the hydraulic drive members, the control valve block further comprising:

The shuttle valve is provided with a first interface, a second interface and a third interface, the first interface is communicated with the first oil port, the second interface is communicated with the second oil port, and the third interface is communicated with the second control valve.

6. A hydraulic drive system according to claim 3, wherein the control valve block comprises:

A plurality of solenoid valves, each of the solenoid valves including a third communication port and a fourth communication port, the third communication port communicating with the first manifold port, the fourth communication port communicating with the first shunt port;

wherein, under the condition that each electromagnetic valve is conducted, each first flow distributing and collecting valve is cut off; each of the first current dividing and collecting valves is conducted under the condition that each of the electromagnetic valves is closed.

7. The hydraulic drive system of claim 1 or 2, wherein the pump body comprises a closed bidirectional variable displacement pump; and/or each of said hydraulic drives comprises a bi-directional variable motor.

8. The hydraulic drive system according to claim 1 or 2, wherein the number of the first flow dividing and collecting valves is two, the hydraulic drive system further comprising:

The second flow dividing and collecting valve is arranged between the pump body and the two first flow dividing and collecting valves, the second flow dividing and collecting valve is provided with a second flow collecting port and two second flow dividing ports, the second flow dividing and collecting ports are communicated with the pump body, and the two second flow dividing and collecting ports are respectively communicated with the two first flow collecting ports.

9. The hydraulic drive system of claim 8, further comprising:

and the two ends of the third control valve are respectively connected with the two second chokes of the second shunt current collecting valve, and are used for conducting the two second chokes under the condition that the two ends of the third control valve have pressure differences.

10. A milling machine, comprising:

The hydraulic drive system according to any one of claims 1 to 9;

a body;

the traveling devices are arranged on the machine body and are respectively connected with the hydraulic driving parts.

11. The milling machine of claim 10, wherein the milling machine is configured to,

The plurality of running devices comprise a first running device and a second running device which are positioned in the diagonal direction, the plurality of hydraulic driving pieces comprise a third hydraulic driving piece and a fourth hydraulic driving piece, the third hydraulic driving piece is connected with the first running device, and the fourth hydraulic driving piece is connected with the second running device; the two first shunt ports of one first shunt and collecting valve are respectively communicated with the third hydraulic driving piece and the fourth hydraulic driving piece; or (b)

In the case where the hydraulic drive system includes a second split-flow collecting valve, two of the first split-flow ports of one of the first split-flow collecting valves communicate with any two of the plurality of hydraulic drive members.