阅读说明：本技术 一种负载敏感控制液压系统 (Load sensitive control hydraulic system ) 是由 李磊 冯海涛 韦保新 于 2021-09-15 设计创作，主要内容包括：本发明属于车辆液压系统技术领域,涉及一种负载敏感控制液压系统,包括液压油箱、负载敏感泵、梭阀、流量放大器、转向器、两个转向油缸和电磁阀,负载敏感泵的S口从液压油箱进油,负载敏感泵的B口连接流量放大器的HP口,流量放大器与转向器具有对应相连的P口、T口、R口、L口和Ls口,流量放大器还设有与两个转向油缸反向并联的CL口和CR口,流量放大器的EF口连接于电磁阀的P口,流量放大器还设有向液压油箱回油的HT口,梭阀的两个进油口分别连接于流量放大器的Ls口和电磁阀的B口,梭阀的出油口连接于负载敏感泵的X口,负载敏感泵还设有向液压油箱泄油的L1口。本液压系统用低成本实现了负载敏感阀的功能,提高了空间利用率和可靠性。(The invention belongs to the technical field of vehicle hydraulic systems, and relates to a load-sensitive control hydraulic system, which comprises a hydraulic oil tank, a load-sensitive pump, a shuttle valve, a flow amplifier and a steering gear, the hydraulic steering system comprises two steering oil cylinders and an electromagnetic valve, wherein an S port of a load sensitive pump is used for feeding oil from a hydraulic oil tank, a B port of the load sensitive pump is connected with an HP port of a flow amplifier, the flow amplifier and the steering gear are provided with a P port, a T port, an R port, an L port and a Ls port which are correspondingly connected, the flow amplifier is also provided with a CL port and a CR port which are reversely connected in parallel with the two steering oil cylinders, an EF port of the flow amplifier is connected with the P port of the electromagnetic valve, the flow amplifier is also provided with an HT port for feeding oil to the hydraulic oil tank, two oil inlets of a shuttle valve are respectively connected with the Ls port of the flow amplifier and the B port of the electromagnetic valve, an oil outlet of the shuttle valve is connected with an X port of the load sensitive pump, and the load sensitive pump is also provided with an L1 port for draining oil to the hydraulic oil tank. The hydraulic system realizes the function of the load sensitive valve with low cost, and improves the space utilization rate and the reliability.)

1. A load sensitive control hydraulic system comprises a hydraulic oil tank, a load sensitive pump, a shuttle valve, a flow amplifier, a steering gear, two steering oil cylinders and an electromagnetic valve, wherein an S port of the load sensitive pump is fed with oil from the hydraulic oil tank, a B port of the load sensitive pump is connected with an HP port of the flow amplifier, the flow amplifier and the steering gear are provided with a P port, a T port, an R port, an L port and an Ls port which are correspondingly connected, the flow amplifier is also provided with a CL port and a CR port which are reversely connected with the two steering oil cylinders in parallel, an EF port of the flow amplifier is connected with the P port of the electromagnetic valve, the flow amplifier is also provided with an HT port for returning oil to the hydraulic oil tank, two oil inlets of the shuttle valve are respectively connected with the Ls port of the flow amplifier and the B port of the electromagnetic valve, and an oil outlet of the shuttle valve is connected with the X port of the load sensitive pump, the load sensitive pump is also provided with an L1 port draining oil to the hydraulic oil tank.

2. The load sensitive control hydraulic system of claim 1, wherein: the port P of the electromagnetic valve is also connected with the port P of a multi-way valve, the port T of the multi-way valve returns oil to the hydraulic oil tank, and the multi-way valve drives a plurality of supporting leg oil cylinders.

3. The load sensitive control hydraulic system of claim 1, wherein: the number of the supporting leg oil cylinders is four.

4. The load sensitive control hydraulic system of claim 1, wherein: and hydraulic locks are arranged at the inlet and the outlet of the supporting leg oil cylinder.

5. The load sensitive control hydraulic system of claim 1, wherein: the P mouth of a switching-over valve is still connected to the P mouth of solenoid valve, the T mouth of switching-over valve is past the hydraulic tank oil return, two parallelly connected dump cylinders of forward between A mouth and the B mouth of switching-over valve.

Technical Field

The invention relates to the technical field of vehicle hydraulic systems, in particular to a load sensitive control hydraulic system.

Background

At present, the requirements of energy conservation, environmental protection and the like are met, and more hydraulic systems adopt variable systems. One of the variable displacement systems is a load sensitive hydraulic system. The principle of the load-sensitive hydraulic system is to control the output of the pressure and flow of the pump according to the requirement of the load, because the load is required to be supplied more or less, so that the power consumption is less and the efficiency is much higher than that of the conventional hydraulic system.

In the prior art, a load sensitive pump and a load sensitive valve are required to be used in a matched manner, the control precision of the load sensitive valve is high, and the control of synchronization and quick response is easy to realize. But the load sensitive valves are expensive. The load sensitive valve has high requirement on the cleanliness of hydraulic oil, and the valve core is easy to be blocked. For a hydraulic system with low requirements, the load sensitive valve is small in size. If all the actuating mechanisms do not share the load-sensitive pump, the pump needs to be added, and the addition of the pump means that the installation space is enlarged, the cost is increased, and the energy consumption is increased.

It is therefore desirable to provide a new hydraulic system designed to achieve control of a load sensitive pump without the use of a load sensitive valve.

Disclosure of Invention

The invention mainly aims to provide a load-sensitive control hydraulic system which can realize the control of a load-sensitive pump under the condition of not using a load-sensitive valve.

The invention realizes the purpose through the following technical scheme: a load sensitive control hydraulic system comprises a hydraulic oil tank, a load sensitive pump, a shuttle valve, a flow amplifier, a steering gear, two steering oil cylinders and an electromagnetic valve, wherein an S port of the load sensitive pump is fed with oil from the hydraulic oil tank, a B port of the load sensitive pump is connected with an HP port of the flow amplifier, the flow amplifier and the steering gear are provided with a P port, a T port, an R port, an L port and an Ls port which are correspondingly connected, the flow amplifier is also provided with a CL port and a CR port which are reversely connected with the two steering oil cylinders in parallel, an EF port of the flow amplifier is connected with the P port of the electromagnetic valve, the flow amplifier is also provided with an HT port for returning oil to the hydraulic oil tank, two oil inlets of the shuttle valve are respectively connected with the Ls port of the flow amplifier and the B port of the electromagnetic valve, and an oil outlet of the shuttle valve is connected with the X port of the load sensitive pump, the load sensitive pump is also provided with an L1 port draining oil to the hydraulic oil tank.

Specifically, the port P of a multi-way valve is further connected to the port P of the electromagnetic valve, the port T of the multi-way valve returns oil to the hydraulic oil tank, and the multi-way valve drives the plurality of supporting leg oil cylinders.

Furthermore, the number of the supporting leg oil cylinders is four.

Furthermore, hydraulic locks are arranged at the inlet and the outlet of the supporting leg oil cylinder.

Specifically, the P mouth of a switching-over valve is still connected to the P mouth of solenoid valve, the T mouth of switching-over valve is past the hydraulic tank oil return, two parallelly connected dump cylinders of forward between A mouth and the B mouth of switching-over valve.

The technical scheme of the invention has the beneficial effects that:

the hydraulic system does not use a load sensitive valve, but realizes the function of the load sensitive valve, can save cost and improve the space utilization rate and reliability.

Drawings

FIG. 1 is a circuit diagram of an embodiment load-sensitive control hydraulic system.

The figures in the drawings represent:

the hydraulic control system comprises a hydraulic oil tank 1, a load sensitive pump 2, a shuttle valve 3, a flow amplifier 4, a steering gear 5, a steering oil cylinder 6, an electromagnetic valve 7, a support leg oil cylinder 8, a hydraulic lock 9, a multi-way valve 10, a dump oil cylinder 11 and a reversing valve 12.

Detailed Description

The present invention will be described in further detail with reference to specific examples.

Example (b):

as shown in figure 1, the load-sensitive control hydraulic system of the invention comprises a hydraulic oil tank 1, a load-sensitive pump 2, a shuttle valve 3, a flow amplifier 4, a steering gear 5, two steering oil cylinders 6 and an electromagnetic valve 7, wherein an S port of the load-sensitive pump 2 is fed with oil from the hydraulic oil tank 1, a B port of the load-sensitive pump 2 is connected with an HP port of the flow amplifier 4, the flow amplifier 4 and the steering gear 5 are provided with a P port, a T port, an R port, an L port and an Ls port which are correspondingly connected, the flow amplifier 4 is also provided with a CL port and a CR port which are reversely connected with the two steering oil cylinders 6 in parallel, an EF port of the flow amplifier 4 is connected with the P port of the electromagnetic valve 7, the flow amplifier 4 is also provided with an HT port for feeding oil to the hydraulic oil tank 1, two oil inlets of the shuttle valve 3 are respectively connected with the Ls port of the flow amplifier 4 and the B port of the electromagnetic valve 7, an oil outlet of the shuttle valve 3 is connected with the X port of the load-sensitive pump 2, the load-sensitive pump 2 is also provided with an L1 port for draining oil to the hydraulic oil tank 1. The load sensitive pump 2 outputs flow and pressure as required.

The working principle of the hydraulic system is as follows: when the engine is started, the electromagnetic valve 7 is not allowed to be electrified, so that the loaded starting of the engine is avoided. An operation button (driving/assisting) is arranged in the cab. The electromagnetic valve 7 is not allowed to be electrified in the driving process, and the operation button is only operated after the hand brake is put down and the parking brake is operated after the hand brake is put down (driving/assisting). Thus, potential safety hazards caused by misoperation in the driving process are avoided. When the steering is not needed, and the electromagnetic valve 7 is not powered, no pressure exists at two ends of the shuttle valve 3, no feedback pressure exists on the load sensitive pump 2, the load sensitive pump 2 only outputs little flow and pressure, and the consumed power is little. The effects of energy conservation and environmental protection are achieved; when the steering operation is needed, the steering gear 5 is operated through a steering wheel, the Ls port on the steering gear 5 realizes the feedback to the load sensitive pump 2 through the shuttle valve 3, and the load sensitive pump 2 realizes the output of pressure and flow at the moment. The direction and the flow of the output oil of the flow amplifier 4 are controlled by the steering gear 5, and the oil output by the flow amplifier 4 enters the steering oil cylinder 6 to realize steering action. The hydraulic system does not use a load sensitive valve, but realizes the function of the load sensitive valve, and can save the cost. The function of the load-sensitive hydraulic system is realized by the electromagnetic valve 7, the electromagnetic valve 7 can be applied to executing mechanisms which do not work simultaneously, and the number of the executing mechanisms can be added without limitation. The safety protection control logic of the electromagnetic valve 7 can avoid economic loss and safety accidents caused by misoperation.

As shown in fig. 1, a port P of the electromagnetic valve 7 is further connected with a port P of a multi-way valve 10, a port T of the multi-way valve 10 returns oil to the hydraulic oil tank 1, and the multi-way valve 10 drives a plurality of support leg oil cylinders 8. The supporting leg oil cylinder 8 is used for driving supporting legs of the vehicle, so that the vehicle can be fixed in place and is prevented from sliding. When the supporting leg oil cylinder needs to act, the electromagnetic valve 7 is electrified, the port P and the port B of the electromagnetic valve 7 are communicated, and the port B feeds back to the load sensitive pump 2 through the shuttle valve 3. When the multi-way valve 10 is operated, the load sensing pump 2 sucks oil through the hydraulic oil tank 1, and the outlet of the load sensing pump 2 enters the HP port of the flow amplifier 4 and is output to the P port of the multi-way valve 10 from the EF port of the flow amplifier 4. The hydraulic oil reaches the supporting leg oil cylinder 8 through the multi-way valve 10 and the hydraulic lock 9, and the return oil of the supporting leg oil cylinder 8 finally returns to the hydraulic oil tank 1 through the T port of the multi-way valve 10 and the multi-way valve 10. The oil output by the load sensitive pump 2 enters through an HP port of the flow amplifier, and exits from an EF port, and the oil output by the EF port continuously feeds back to the load sensitive pump 2 through a P port and a B port of the electromagnetic valve 7 through the shuttle valve 3.

As shown in fig. 1, the number of the leg cylinders 8 is four. Each supporting leg oil cylinder 8 controls one supporting leg respectively, so that each wheel can be provided with one supporting leg, and the vehicle can be better guaranteed to be stable.

As shown in fig. 1, hydraulic locks 9 are arranged at the inlet and the outlet of the leg oil cylinder 8. The hydraulic lock 9 can be locked when the supporting leg oil cylinder 8 reaches the stop position, so that the danger caused by sudden pressure loss of the supporting leg is prevented.

As shown in fig. 1, the port P of the electromagnetic valve 7 is also connected with the port P of a reversing valve 12, the port T of the reversing valve 12 returns oil to the hydraulic oil tank 1, and two dump cylinders 11 are connected in parallel between the port a and the port B of the reversing valve 12 in the forward direction. When the reversing valve 12 is operated, the load-sensitive pump 2 sucks oil through the hydraulic oil tank 1, and the outlet of the load-sensitive pump 2 enters the HP port of the flow amplifier 4 and is output to the P port of the reversing valve 12 from the EF port of the flow amplifier 4. The hydraulic oil reaches the dump cylinder 11 through the reversing valve 12, and the return oil of the dump cylinder 11 finally returns to the hydraulic oil tank 1 through the T port of the reversing valve 12 through the reversing valve 12. The two self-discharging oil cylinders 11 can enable the two sides of the car hopper to be synchronously lifted to dump and discharge. Thus, the common reversing valve 12 is used for realizing one pump with multiple purposes of the load-sensitive pump 2, the requirement on the cleanliness of oil is not high, the probability of valve core clamping stagnation is reduced, the failure rate is reduced, the risks of maintenance and production halt are reduced, the installation space is saved, and the energy consumption and the cost are reduced.

What has been described above are merely some embodiments of the present invention. It will be apparent to those skilled in the art that various changes and modifications can be made without departing from the inventive concept thereof, and these changes and modifications can be made without departing from the spirit and scope of the invention.