CN212455013U - Hydraulic control system and fire engine - Google Patents
Hydraulic control system and fire engine Download PDFInfo
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- CN212455013U CN212455013U CN202021578525.0U CN202021578525U CN212455013U CN 212455013 U CN212455013 U CN 212455013U CN 202021578525 U CN202021578525 U CN 202021578525U CN 212455013 U CN212455013 U CN 212455013U
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Abstract
The utility model provides a hydraulic control system and fire engine, wherein, hydraulic control system includes: a hydraulic actuator; the hydraulic oil pump is connected to the hydraulic execution element through an oil supply circuit; the first reversing valve is arranged on the oil supply path; one end of the standby oil way is communicated with the oil supply way, and the other end of the standby oil way is communicated with the oil tank; and the second reversing valve is arranged on the oil waiting path. The utility model provides a hydraulic control system, possess standby form and hydraulic actuator working form, in standby form, control hydraulic oil pump opens, supply with the hydraulic oil in the oil tank in the standby oil circuit, the hydraulic oil of low pressure low discharge state is at oil feed way and standby oil circuit inner loop, this inner loop oil circuit has radiating effect simultaneously concurrently, need the during operation at hydraulic actuator, can enter into hydraulic actuator working form, hydraulic control system's response efficiency has been improved, the specially adapted needs the operating mode that hydraulic actuator responded as early as possible.
Description
Technical Field
The utility model relates to a hydraulic pressure technical field particularly, relates to a hydraulic control system and a fire engine.
Background
In a hydraulic system, hydraulic oil in an oil tank is delivered to a hydraulic actuator in a high-pressure mode by starting a hydraulic oil pump, but certain time is required for pumping out and pressurizing the hydraulic oil in the oil tank and then supplying the hydraulic oil to the hydraulic actuator, so that the conventional hydraulic system needs certain response time, and the response speed of the hydraulic actuator is slow.
For example, in the field of fire fighting vehicles, when a fire fighting vehicle is switched to a water pumping state from a driving state, a support leg and an arm support of the fire fighting vehicle need to be driven by a hydraulic system, and the hydraulic system is slow in response, so that the fire fighting vehicle is slow in response and easily misses the best time for fire extinguishing.
SUMMERY OF THE UTILITY MODEL
The utility model discloses aim at solving one of the technical problem that exists among the prior art at least.
Therefore, the utility model discloses the first aspect provides a hydraulic control system.
The utility model discloses the second aspect provides a fire engine.
In view of this, according to the utility model discloses a first aspect provides a hydraulic control system, includes: a hydraulic actuator; the hydraulic oil pump is connected to the hydraulic execution element through an oil supply circuit; the first reversing valve is arranged on the oil supply path and is positioned between the hydraulic oil pump and the hydraulic actuating element; one end of the standby oil way is communicated with the oil supply way, the other end of the standby oil way is communicated with the oil tank, and the joint of the standby oil way and the oil supply way is positioned between the first reversing valve and the hydraulic oil pump; and the second reversing valve is arranged on the oil waiting path.
The utility model provides a hydraulic control system, in the course of the work, can possess standby form and hydraulic actuator working form, in standby form, control first switching-over valve outage or switching-over in order to break off the route between oil feed way and the hydraulic actuator, control second switching-over valve electrification and switching-over in order to communicate standby oil circuit, control hydraulic oil pump opens, supply the hydraulic oil in the oil tank to standby oil circuit, the hydraulic oil of low pressure low discharge state circulates in oil feed way and standby oil circuit, this internal circulation oil circuit has the radiating effect simultaneously, when hydraulic actuator needs work, can enter hydraulic actuator working form, first switching-over valve electrification and switching-over intercommunication oil feed way, the switching-over of second switching-over is in order to close standby oil circuit, high-pressure hydraulic oil at standby oil circuit and oil feed way internal circulation can directly supply to hydraulic actuator, the response efficiency of the hydraulic control system is improved, and the hydraulic control system is particularly suitable for the working condition that the hydraulic actuating element needs to respond as early as possible.
For example, be in the utility model provides a hydraulic control system uses at the fire engine, can make hydraulic control system be in the standby form in the engineering of fire engine form, after the fire engine reachd the scene of a fire, can switch to hydraulic actuator working form via the standby form, can improve the response efficiency of fire engine, can put out a fire as early as possible in order to reduce stretching of intensity of a fire.
It can be understood that the utility model provides a hydraulic control system also can get electricity and the switching-over is with the route between intercommunication oil feed way and the hydraulic actuator through first switching-over valve, need not to directly start hydraulic actuator working form through the standby form, is applicable to the operating mode environment that requires less to hydraulic actuator response efficiency, can reduce the opening time of hydraulic oil pump, more the energy can be saved.
Additionally, the utility model provides an among the above-mentioned technical scheme hydraulic control system can also have following additional technical characteristics:
in the technical scheme, further, an oil inlet valve port of the first reversing valve is communicated with the hydraulic oil pump, and an execution valve port of the first reversing valve is communicated with the hydraulic execution element; an oil inlet valve port of the second reversing valve is communicated with the standby oil way, and a first execution valve port of the second reversing valve is communicated with the oil tank; the hydraulic oil pump is a load-sensitive pump, the output end of the load-sensitive pump is communicated with the oil inlet valve port of the first reversing valve through an oil supply path, and the load-sensitive port of the load-sensitive pump is communicated with the oil return valve port of the first reversing valve through a constant-pressure oil path; the second reversing valve is arranged on the standby oil way and the constant-pressure oil way, the load sensitive port of the load sensitive pump is communicated with the second execution valve port of the second reversing valve, and the oil return valve port of the second reversing valve is communicated with the oil return valve port of the first reversing valve.
In the technical scheme, the connection relation of the valve ports of the first reversing valve, the connection relation of the valve ports of the second reversing valve, the type of the hydraulic oil pump and the arrangement of the constant-pressure oil path are further provided, the hydraulic oil pump is a load-sensitive pump, and the load-sensitive pump is wider in application range as a variable pump. The second reversing valve is arranged on the standby oil way and the constant pressure oil way and can control the on-off of the standby oil way and the constant pressure oil way, so that the hydraulic control system further has a constant pressure working state, in the working process, after the hydraulic control system is switched to the working state of the hydraulic actuating element through the standby state, the first reversing valve is firstly electrified and reversed, the oil supply way is communicated with the hydraulic actuating element, the hydraulic oil supplied by the hydraulic oil pump is conveyed to the hydraulic actuating element, the hydraulic actuating element is put into a working state as soon as possible, the return oil of the hydraulic control system in this state can be returned to the oil tank through the oil return port of the hydraulic actuator and the standby oil passage, when the constant-pressure working state needs to be started after the hydraulic execution element enters the working state, the second reversing valve is controlled to reverse, the constant-pressure oil way is opened, and at the moment, return oil of the hydraulic control system returns to the load sensitive opening of the load sensitive pump through the constant-pressure oil way.
For example, the utility model discloses a hydraulic control system can start the standby form during the fire engine is used to the fire engine, switches into the state of fetching water at the fire engine via the form state, when needing control landing leg and cantilever crane to stretch out, can control hydraulic system and enter into hydraulic actuator working form, and is firm fixed at the landing leg, and after the cantilever crane extended to anticipated position, hydraulic control system can enter into constant voltage operation form, and the sensitive pump of load enters into constant voltage operation mode.
In any of the above technical solutions, further, the hydraulic control system further includes: and the first damping hole is arranged on the constant-pressure oil path and is positioned between the second reversing valve and the load sensitive port.
In the technical scheme, the hydraulic oil pump further comprises a first damping hole, so that the hydraulic oil returns to a load sensitive port of the load sensitive pump after passing through the first damping hole in a constant pressure operation state, and displacement impact of the hydraulic oil pump can be reduced through the arrangement of the first damping hole.
In any of the above technical solutions, further, the hydraulic control system further includes: the first check valve is positioned on the constant-pressure oil way, the oil outlet valve port of the first check valve is communicated with the constant-pressure oil way, the communication position of the oil inlet valve port of the first check valve and the constant-pressure oil way is positioned between the first damping hole and the load sensitive port, and the communication position of the oil outlet valve of the first check valve and the constant-pressure oil way is positioned between the first damping hole and the second execution valve port of the second reversing valve.
In this technical scheme, further included first check valve, can avoid oil pump discharge capacity instantaneous change through the setting of first check valve, lead to oil return volume to change and strike the hydraulic oil pump, reduce the impact of hydraulic oil pump discharge capacity, can improve the life of hydraulic oil pump and hydraulic control system's stability.
In any of the above technical solutions, further, the hydraulic control system further includes: a plurality of third directional control valves; the oil supply path includes: the hydraulic oil pump is communicated with the main road; the branch circuits are communicated with the main circuit; the hydraulic actuating elements are multiple in number, each branch is correspondingly connected with one or more hydraulic actuating elements and one third reversing valve, an oil return valve port of each third reversing valve is communicated with an oil tank, an oil inlet valve port of each third reversing valve is communicated with the main road, and each actuating valve port of each third reversing valve is communicated with one hydraulic actuating element.
In the technical scheme, the oil supply path further comprises a main path and a plurality of branch paths, the branch paths are communicated with the main path, and each branch path is provided with one hydraulic actuating element and one third reversing valve, so that on one hand, one hydraulic oil pump can drive the hydraulic actuating elements to work, and the working efficiency of the hydraulic control system is improved; on the other hand, the connection and disconnection of each branch can be controlled through the arrangement of the third reversing valve, so that the controllability of the hydraulic control system is stronger, and the application range of the hydraulic control system is widened.
In any of the above technical solutions, further, the hydraulic control system further includes: and the second damping hole is arranged on the oil waiting path and is positioned between the oil tank and the second reversing valve.
In the technical scheme, the hydraulic control system further comprises a second damping hole arranged on the standby oil way, and the flow of hydraulic oil passing through the second reversing valve in the standby oil way in the standby state can be controlled through the second damping hole, so that the hydraulic control system is safer to use.
In any of the above technical solutions, further, the hydraulic control system further includes: and the second one-way valve is arranged on the oil supply path and is positioned between the joint of the standby oil path and the oil supply path and the hydraulic oil pump.
In the technical scheme, the hydraulic control system further comprises a second one-way valve, the pressure of hydraulic oil in the oil supply way can be controlled through the arrangement of the second one-way valve, so that the pressure of the oil way in the hydraulic control system is controllable, and the hydraulic control system is safer to use.
In any of the above technical solutions, further, the hydraulic control system further includes: and the radiator is arranged on the oil waiting path and is positioned between the second reversing valve and the oil tank.
In the technical scheme, the hydraulic control system further comprises a radiator, and the hydraulic oil returns to the oil tank after passing through the radiator in the standby state through the arrangement of the radiator, so that the temperature of the hydraulic oil can be reduced, and the hydraulic control system is safer to use.
Specifically, an oil return port of the hydraulic actuator can be communicated with the radiator, so that oil returned by the hydraulic actuator passes through the radiator and then returns to the oil tank, and the effect of cooling hydraulic oil is achieved.
According to the utility model discloses a second aspect provides a fire engine, include: the supporting legs are arranged on the chassis; the arm support is arranged on the chassis; in the hydraulic control system according to any one of the above technical solutions, the hydraulic actuator of the hydraulic control system is connected to the support leg and the arm support and used for driving the arm support and the support leg to extend or retract.
The utility model provides a fire engine, because of the fire engine has included foretell hydraulic control system, consequently fire engine possesses hydraulic control system's whole beneficial technological effect.
Additionally, the utility model provides an among the above-mentioned technical scheme hydraulic control system can also have following additional technical characteristics:
in the above technical solution, further, the hydraulic actuator includes: the supporting leg oil cylinder is connected to the supporting leg and used for driving the supporting leg to extend out or retract; and the arm support oil cylinder is connected to the arm support and is used for driving the arm support to extend out or retract.
In the technical scheme, the hydraulic actuator is further provided, the hydraulic actuator comprises a support oil cylinder and an arm support oil cylinder, the support oil cylinder and the arm support oil cylinder respectively drive a support and an arm support to work, and the running safety of the fire fighting truck can be improved.
Additional aspects and advantages of the invention will be set forth in part in the description which follows, or may be learned by practice of the invention.
Drawings
The above and/or additional aspects and advantages of the present invention will become apparent and readily appreciated from the following description of the embodiments, taken in conjunction with the accompanying drawings of which:
fig. 1 shows a schematic structural diagram of a hydraulic control system provided according to an embodiment of the present invention;
fig. 2 shows a schematic structural diagram of a fire fighting vehicle provided according to an embodiment of the present invention;
fig. 3 is a flowchart illustrating a first step of a method for controlling standby operation of a fire fighting vehicle according to some embodiments of the present invention;
fig. 4 is a flowchart illustrating a second step of a method for controlling standby operation of a fire fighting vehicle according to some embodiments of the present invention;
fig. 5 is a flowchart illustrating a third step of a method for controlling standby operation of a fire fighting vehicle according to some embodiments of the present invention;
fig. 6 is a flowchart illustrating a fourth step of a fire fighting vehicle operation standby control method according to some embodiments of the present invention.
Wherein, the correspondence between the reference numbers and the component names in fig. 1 and fig. 2 is:
2 hydraulic actuating element, 4 hydraulic oil pump, 6 first change-over valve, 8 second change-over valve, 10 first damping hole, 12 second damping hole, 14 second check valve, 16 radiator, 18 landing leg, 20 arm support, 22 first check valve, 24 center rotary joint, 26 oil tank, 602 oil inlet valve port of first change-over valve, 604 execution valve port of first change-over valve, 606 oil return valve port of first change-over valve, 802 oil inlet valve port of second change-over valve, 804 first execution valve port of second change-over valve, 806 second execution valve port of second change-over valve, 808 oil return valve port of second change-over valve, 402 load sensing port.
Detailed Description
In order to make the aforementioned objects, features and advantages of the present invention more clearly understood, the present invention will be described in further detail with reference to the accompanying drawings and detailed description. It should be noted that the embodiments and features of the embodiments of the present application may be combined with each other without conflict.
In the following description, numerous specific details are set forth in order to provide a thorough understanding of the present invention, however, the present invention may be practiced in other ways than those specifically described herein, and therefore the scope of the present invention is not limited by the specific embodiments disclosed below.
A hydraulic control system and a fire engine according to some embodiments of the present invention are described below with reference to fig. 1 to 6.
Example one
As shown in fig. 1, an embodiment of the present invention provides a hydraulic control system, including: the hydraulic control system comprises a hydraulic actuator 2, a hydraulic oil pump 4, a first reversing valve 6, a standby oil path and a second reversing valve 8.
The hydraulic oil pump 4 is connected to the hydraulic actuator 2 through an oil supply path; the first reversing valve 6 is arranged on the oil supply path and is positioned between the hydraulic oil pump 4 and the hydraulic actuator 2; one end of the standby oil way is communicated with the oil supply way, the other end of the standby oil way is communicated with the oil tank 26, and the joint of the standby oil way and the oil supply way is positioned between the first reversing valve 6 and the hydraulic oil pump 4; the second reversing valve 8 is arranged on the oil waiting path.
The utility model provides a hydraulic control system, in the course of the work, can possess standby form and hydraulic actuator 2 working form, in standby form, control first switching-over valve 6 outage or switching-over in order to break off the route between oil feed way and the hydraulic actuator 2, control second switching-over valve 8 electrification and switching-over in order to communicate standby oil way, control hydraulic oil pump 4 and open, supply the hydraulic oil in the oil tank 26 to standby oil way, the hydraulic oil of low pressure low discharge state circulates in standby oil way, when hydraulic actuator 2 needs work, can enter hydraulic actuator 2 working form, first switching-over valve 6 electrification and switching-over intercommunication oil feed way, second switching-over valve 8 switching-over is in order to close standby oil way, hydraulic control system switches over to the constant voltage mode, the low pressure low discharge hydraulic oil that circulates in standby oil way and oil feed way can change high-pressure hydraulic oil into and directly supply to hydraulic actuator 2, the response efficiency of the hydraulic control system is improved, and the hydraulic control system is particularly suitable for the working condition that the hydraulic actuating element 2 needs to respond as early as possible.
For example, be in the utility model provides a hydraulic control system uses at the fire engine, can make hydraulic control system be in the standby form in the engineering of fire engine form, after the fire engine reachd the scene of a fire, can switch over to hydraulic actuator 2 working form via the standby form, can improve the response efficiency of fire engine, can put out a fire as early as possible in order to reduce stretching of intensity of a fire.
It can be understood that the utility model provides a hydraulic control system also can get electricity and the switching-over is with the route between intercommunication oil feed way and the hydraulic actuator 2 through first switching-over valve 6, need not to directly start hydraulic actuator 2 working form through the standby form, is applicable to the operating mode environment that requires lower to hydraulic actuator 2 response efficiency, can reduce the opening time of hydraulic oil pump 4, more the energy can be saved.
Example two
As shown in fig. 1, an embodiment of the present invention provides a hydraulic control system, including: the hydraulic control system comprises a hydraulic actuator 2, a hydraulic oil pump 4, a first reversing valve 6, a standby oil path and a second reversing valve 8.
The hydraulic oil pump 4 is connected to the hydraulic actuator 2 through an oil supply path; the first reversing valve 6 is arranged on an oil supply path, the hydraulic oil pump 4 is communicated with an oil inlet valve port 602 of the first reversing valve, and the hydraulic actuating element 2 is communicated with an actuating valve port 604 of the first reversing valve; one end of the standby oil way is communicated with the oil supply way, the other end of the standby oil way is communicated with the oil tank 26, and the joint of the standby oil way and the oil supply way is positioned between the first reversing valve 6 and the hydraulic oil pump 4; the second direction valve 8 is disposed on the standby oil path, the standby oil path is communicated with the oil inlet port 802 of the second direction valve, and the first implement port 804 of the second direction valve is communicated with the oil tank 26.
Further, the hydraulic oil pump 4 is a load-sensitive pump, an output end of the load-sensitive pump is communicated with the oil inlet valve port 602 of the first reversing valve through an oil supply path, and the load-sensitive port 402 of the load-sensitive pump is communicated with the oil return valve port 606 of the first reversing valve through a constant-pressure oil path; the second direction valve 8 is disposed on the standby oil path and the constant pressure oil path, the load sensing port 402 of the load sensing pump is communicated with the second execution valve port 806 of the second direction valve, and the oil return valve port 808 of the second direction valve is communicated with the oil return valve port 606 of the first direction valve.
In this embodiment, the type of the hydraulic oil pump 4 and the arrangement of the constant-pressure oil path are further provided, the hydraulic oil pump 4 is a load-sensitive pump, and the application range of the load-sensitive pump as a variable pump is wider. The second reversing valve 8 is arranged on the standby oil way and the constant pressure oil way and can control the on-off of the standby oil way and the constant pressure oil way, so that the hydraulic control system further has a constant pressure working state, in the working process, after the hydraulic control system is switched to the working state of the hydraulic actuating element 2 through the standby state, the first reversing valve 6 is firstly electrified and reversed, the oil supply channel is communicated with the hydraulic actuating element 2, the hydraulic oil supplied by the hydraulic oil pump 4 is conveyed to the hydraulic actuating element 2, the hydraulic actuating element 2 is put into a working state as soon as possible, the return oil of the hydraulic control system in this state can be returned to the oil tank 26 through the oil return port of the hydraulic actuator 2 and the standby oil passage, when the constant-pressure working state needs to be started after the hydraulic execution element 2 enters the working state, the second reversing valve 8 is controlled to reverse, the constant-pressure oil way is opened, and at the moment, return oil of the hydraulic control system returns to the load sensitive port 402 of the load sensitive pump through the constant-pressure oil way.
For example, the utility model discloses a hydraulic control system can start the standby form during the fire engine is used to the fire engine, switches into the state of fetching water at the fire engine via the state of traveling, when needing to control landing leg 18 and cantilever crane 20 and stretch out, can control hydraulic system and go into constant voltage operation mode, makes landing leg 18 and cantilever crane 20 extend to the anticipated position as early as possible, when not doing landing leg 18 and cantilever crane 20, and the sensitive pump of load gets into the standby mode of low discharge.
EXAMPLE III
As shown in fig. 1, an embodiment of the present invention provides a hydraulic control system, including: the hydraulic control system comprises a hydraulic actuator 2, a hydraulic oil pump 4, a first reversing valve 6, a standby oil path and a second reversing valve 8.
The hydraulic oil pump 4 is connected to the hydraulic actuator 2 through an oil supply path; the first reversing valve 6 is arranged on an oil supply path, the hydraulic oil pump 4 is communicated with an oil inlet valve port 602 of the first reversing valve, and the hydraulic actuating element 2 is communicated with an actuating valve port 604 of the first reversing valve; one end of the standby oil way is communicated with the oil supply way, the other end of the standby oil way is communicated with the oil tank 26, and the joint of the standby oil way and the oil supply way is positioned between the first reversing valve 6 and the hydraulic oil pump 4; the second direction valve 8 is disposed on the standby oil path, the standby oil path is communicated with the oil inlet port 802 of the second direction valve, and the first implement port 804 of the second direction valve is communicated with the oil tank 26.
Further, the hydraulic oil pump 4 is a load-sensitive pump, an output end of the load-sensitive pump is communicated with the oil inlet valve port 602 of the first reversing valve through an oil supply path, and the load-sensitive port 402 of the load-sensitive pump is communicated with the oil return valve port 606 of the first reversing valve through a constant-pressure oil path; the second direction valve 8 is disposed on the standby oil path and the constant pressure oil path, the load sensing port 402 of the load sensing pump is communicated with the second execution valve port 806 of the second direction valve, and the oil return valve port 808 of the second direction valve is communicated with the oil return valve port 606 of the first direction valve.
Further, the hydraulic control system further includes: a first orifice 10, arranged in the constant pressure oil path, between the second directional control valve 8 and the load-sensitive port 402; the first check valve 22 is located on the constant pressure oil path, the oil outlet port of the first check valve 22 is communicated with the constant pressure oil path, the communication position between the oil inlet port of the first check valve 22 and the constant pressure oil path is located between the first damping hole 10 and the load sensitive port 402, and the communication position between the oil outlet valve of the first check valve 22 and the constant pressure oil path is located between the first damping hole 10 and the second execution port 806 of the second directional control valve.
In this embodiment, the first damping hole 10 and the first check valve 22 are further included, so that the hydraulic oil returns to the load sensitive port 402 of the load sensitive pump after passing through the first damping hole 10 in the constant pressure operation state, and the arrangement of the first check valve 22 can avoid the instantaneous change of the oil pump displacement, which causes the instantaneous flow of the hydraulic system to impact the hydraulic oil pump 4, reduce the displacement impact of the hydraulic oil pump 4, and can improve the service life of the hydraulic oil pump 4 and the stability of the hydraulic control system.
Example four
As shown in fig. 1, an embodiment of the present invention provides a hydraulic control system, including: the hydraulic control system comprises a hydraulic actuator 2, a hydraulic oil pump 4, a first reversing valve 6, a standby oil path and a second reversing valve 8.
The hydraulic oil pump 4 is connected to the hydraulic actuator 2 through an oil supply path; the first reversing valve 6 is arranged on an oil supply path, the hydraulic oil pump 4 is communicated with an oil inlet valve port 602 of the first reversing valve, and the hydraulic actuating element 2 is communicated with an actuating valve port 604 of the first reversing valve; one end of the standby oil way is communicated with the oil supply way, the other end of the standby oil way is communicated with the oil tank 26, and the joint of the standby oil way and the oil supply way is positioned between the first reversing valve 6 and the hydraulic oil pump 4; the second direction valve 8 is disposed on the standby oil path, the standby oil path is communicated with the oil inlet port 802 of the second direction valve, and the first implement port 804 of the second direction valve is communicated with the oil tank 26.
Further, the hydraulic control system further includes: a plurality of third directional control valves; the oil supply path includes: the hydraulic oil pump 4 is communicated with the main road; the branch circuits are communicated with the main circuit; the number of the hydraulic actuating elements 2 is multiple, each branch is correspondingly connected with one or more hydraulic actuating elements 2 and a third reversing valve, an oil return valve port of each third reversing valve is communicated with the oil tank 26, an oil inlet valve port of each third reversing valve is communicated with the main road, and each actuating valve port of each third reversing valve is communicated with one hydraulic actuating element 2.
In this embodiment, the oil supply path further includes a main path and a plurality of branches, the plurality of branches are communicated with the main path, and each branch is provided with one hydraulic actuator 2 and one third reversing valve, so that on one hand, one hydraulic oil pump 4 can drive the plurality of hydraulic actuators 2 to work, and the working efficiency of the hydraulic control system is improved; on the other hand, the connection and disconnection of each branch can be controlled through the arrangement of the third reversing valve, so that the controllability of the hydraulic control system is stronger, and the application range of the hydraulic control system is widened.
EXAMPLE five
As shown in fig. 1, further to any one of the first to fourth embodiments, the hydraulic control system further includes: and the second damping hole 12 is arranged on the oil waiting path and is positioned between the oil tank 26 and the second reversing valve 8.
In this embodiment, a second orifice 12 is further provided in the standby oil path, and the second orifice 12 can be provided to control the flow rate of the hydraulic oil passing through the second directional valve 8 in the standby oil path in the standby mode. The second damping hole 12 can control the discharge capacity of the hydraulic oil pump 4 in the standby state, so as to control the flow in the standby oil path, and the small-flow hydraulic oil enters the radiator for oil return and heat dissipation, so that the hydraulic control system is safer to use.
EXAMPLE six
As shown in fig. 1, on the basis of any one of the first to fourth embodiments, the hydraulic control system further includes: and the second check valve 14 is arranged on the oil supply path and is positioned between the joint of the standby oil path and the oil supply path and the hydraulic oil pump 4.
In this embodiment, a second check valve 14 is further included, and the pressure of the hydraulic oil in the oil supply path can be controlled through the setting of the second check valve 14, so that the pressure of the oil path in the hydraulic control system is controllable, the hydraulic system is prevented from impacting the hydraulic oil pump 4, and the use of the hydraulic control system is safer.
EXAMPLE seven
As shown in fig. 1, on the basis of any one of the first to fourth embodiments, the hydraulic control system further includes: and the radiator 16 is arranged on the oil waiting path and is positioned between the second reversing valve 8 and the oil tank 26.
In this embodiment, a radiator 16 is further included, and by setting the radiator 16, the hydraulic oil passes through the radiator 16 and then returns to the oil tank 26 in the standby mode, so that the temperature of the hydraulic oil can be reduced, and the hydraulic control system is safer to use.
Specifically, the oil return port of the hydraulic actuator 2 may be communicated with the radiator 16, so that the return oil of the hydraulic actuator 2 passes through the radiator 16 and then returns to the oil tank 26, so as to achieve the effect of cooling the hydraulic oil.
Example eight
As shown in fig. 2, an embodiment of the present invention provides a fire fighting vehicle, including: the supporting legs 18 are arranged on the chassis; the arm support 20 is arranged on the chassis; in the hydraulic control system according to any of the embodiments, the hydraulic actuator 2 of the hydraulic control system includes a support oil cylinder and a boom oil cylinder, the support oil cylinder is connected to the support 18 and used for driving the support 18 to extend or retract, and the boom oil cylinder is connected to the boom 20 and used for driving the boom 20 to extend or retract.
The fire engine that this embodiment provided because of the fire engine has included foretell hydraulic control system, therefore the fire engine possesses hydraulic control system's whole beneficial technological effect.
Specifically, the hydraulic control system further includes: a plurality of third directional control valves; the oil supply path includes: the hydraulic oil pump 4 is communicated with the main road; the branch circuits are communicated with the main circuit; the number of the hydraulic actuating elements 2 is multiple, each branch is correspondingly connected with one hydraulic actuating element 2 and one third reversing valve, an oil return valve port of each third reversing valve is communicated with the oil tank 26, an oil inlet valve port of each third reversing valve is communicated with the main path, and an actuating valve port of each third reversing valve is communicated with one hydraulic actuating element 2. The plurality of branches are divided into two groups, one group of branches is communicated with the arm support 20, the other group of branches is communicated with the supporting leg 18, and a central rotary joint 24 is arranged on the branch communicated with the arm support.
Example nine
As shown in fig. 3, an embodiment of the present invention provides a method for controlling standby operation of a fire fighting truck, which is used for the above fire fighting truck, and the method for controlling standby operation of the fire fighting truck includes:
step 302: receiving a standby instruction of the fire fighting truck, and starting a hydraulic oil pump;
step 304: controlling the first reversing valve and the second reversing valve to reverse, disconnecting a passage between the oil supply path and the hydraulic actuating element, and conducting the standby oil path to enable hydraulic oil to flow through the standby oil path and return to the oil tank;
step 306: and receiving an operation instruction of the fire fighting truck, controlling the first reversing valve to reverse, then controlling the second reversing valve to reverse, conducting the oil inlet valve port and the execution valve port of the first reversing valve, and disconnecting the standby oil way to supply the hydraulic oil to the hydraulic execution element through the oil supply way.
The utility model provides a fire engine operation standby control method, when receiving the standby instruction of the fire engine, responding to the standby instruction of the fire engine, the fire engine enters the standby state, and the hydraulic oil pump is started; the first reversing valve and the second reversing valve are controlled to be powered off, so that the hydraulic oil flows through the standby oil way and returns to the oil tank, the response efficiency of the fire fighting truck can be improved, and the hydraulic oil can dissipate heat in a standby state; at the moment, hydraulic oil in the hydraulic control system enters the oil return tank with the damping hole for heat dissipation, the damping hole can control the discharge capacity of the hydraulic oil pump 4, and further the flow of the standby oil way is controlled, heating caused by low-pressure large-flow oil return is avoided, when an operation instruction is received, the fire fighting truck enters the working state of the hydraulic execution element, the first reversing valve is controlled to reverse, the oil inlet valve port and the execution valve port of the first reversing valve are conducted, the hydraulic oil is supplied to the hydraulic execution element or the third reversing valve connected with the hydraulic execution element through the oil supply way and then returns to the oil tank, and the arm support and the landing leg of the fire fighting truck can enter the working state.
Example ten
As shown in fig. 4, an embodiment of the present invention provides a method for controlling standby operation of a fire fighting truck, which is used for the above fire fighting truck, and the method for controlling standby operation of the fire fighting truck includes:
step 502: receiving a standby instruction of the fire fighting truck, and starting a hydraulic oil pump;
step 504: controlling the first reversing valve and the second reversing valve to be powered off so as to cut off a passage between the oil supply way and the hydraulic actuating element and conduct the standby oil way to enable the hydraulic oil to flow through the standby oil way and return to the oil tank;
step 506: and receiving an operation instruction of the fire fighting truck, controlling the first reversing valve to reverse, then controlling the second reversing valve to reverse, conducting the oil inlet valve port and the execution valve port of the first reversing valve, and disconnecting the standby oil way to supply the hydraulic oil to the hydraulic execution element through the oil supply way.
In the technical scheme, the specific step that the hydraulic oil pump returns to the oil tank through the standby oil way is further provided, the first reversing valve cuts off the passage of the oil supply way by cutting off the first reversing valve and cutting off the second reversing valve, and the oil inlet valve port of the second reversing valve is communicated with the first execution valve port of the second reversing valve, so that the hydraulic oil can return to the oil tank through the standby oil way.
EXAMPLE eleven
As shown in fig. 5, the hydraulic oil pump is a load-sensitive pump, an output end of the load-sensitive pump is communicated with an oil inlet valve port of the first reversing valve through an oil supply path, and a load-sensitive port of the load-sensitive pump is communicated with an oil return valve port of the first reversing valve through a constant-pressure oil path; the second reversing valve is arranged on the standby oil way and the constant-pressure oil way, the load sensitive port of the load sensitive pump is communicated with the second execution valve port of the second reversing valve, and the fire fighting truck operation standby control method comprises the following steps of:
step 702: receiving a standby instruction of the fire fighting truck, and starting a hydraulic oil pump;
step 704: controlling the first reversing valve and the second reversing valve to be powered off so as to cut off a passage between the oil supply way and the hydraulic actuating element and conduct the standby oil way to enable the hydraulic oil to flow through the standby oil way and return to the oil tank;
step 706: receiving an operation instruction of the fire fighting truck, and controlling the first reversing valve to reverse so that the oil inlet valve port of the first reversing valve is communicated with the execution valve port;
step 708: and controlling the second reversing valve to reverse so that an oil return valve port of the second reversing valve is communicated with a second execution valve port of the second reversing valve, and the hydraulic oil is supplied to the hydraulic execution element through the oil supply path and then returns to the load sensitive port through the constant pressure oil path.
In the technical scheme, the fire fighting truck is further provided with a constant pressure working state, in the working process, after a hydraulic control system is switched to the working state of a hydraulic execution element through a standby state, a first reversing valve is electrically reversed to enable an oil supply path to be communicated with the hydraulic execution element, hydraulic oil supplied by a hydraulic oil pump is conveyed to the hydraulic execution element to enable the hydraulic execution element to be put into the working state as soon as possible, oil return of the hydraulic control system in the state can return to an oil tank through an oil return port of the hydraulic execution element and the standby oil path, when the constant pressure working state is required to be started after the hydraulic execution element enters the working state, the second reversing valve is controlled to be electrically reversed, an oil return valve port of the second reversing valve is communicated with a second execution valve port to start a constant pressure oil path, and at the moment, the oil return of the hydraulic control system returns to a load sensitive port of a load sensitive pump through the, the first reversing valve is firstly electrified, the second reversing valve is then electrified, the first reversing valve is firstly electrified, low-pressure hydraulic oil enters the support leg or the arm frame multi-way valve to standby, then the second reversing valve is electrified, the low-pressure hydraulic oil in a standby oil way is immediately converted into high-pressure hydraulic oil to be supplied to the executing element to act, the process that a load-sensitive pump needs to feed back a control signal to the oil pump from the hydraulic executing element is avoided, the response speed of the hydraulic executing element is improved, further, a damping hole of a hydraulic control system and the first one-way valve can prevent the hydraulic oil pump from being impacted, the hydraulic oil pump is in a constant-pressure mode at the moment, and further, the time difference between the electrification of the second reversing valve and the electrification of the first reversing valve is 1-5 s.
Example twelve
As shown in fig. 6, an embodiment of the present invention provides a method for controlling standby operation of a fire fighting truck, wherein the hydraulic control system further includes: a plurality of third directional control valves; the oil supply path includes: the hydraulic oil pump is communicated with the main road; a plurality of branches are communicated with the main road; under the condition that each branch is correspondingly connected with a hydraulic executive component and a third reversing valve, the oil return valve port of each third reversing valve is communicated with an oil tank, the oil inlet valve port of each third reversing valve is communicated with the main road, and the execution valve port of each third reversing valve is communicated with one hydraulic executive component, the fire fighting truck operation standby control method comprises the following steps:
step 902: receiving a standby instruction of the fire fighting truck, and starting a hydraulic oil pump;
step 904: controlling the first reversing valve and the second reversing valve to reverse, disconnecting a passage between the oil supply path and the hydraulic actuating element, and conducting the standby oil path to enable hydraulic oil to flow through the standby oil path and return to the oil tank;
step 906: receiving an operation instruction of the fire fighting truck, controlling the first reversing valve to reverse, then controlling the second reversing valve to reverse, conducting the oil inlet valve port and the execution valve port of the first reversing valve, and disconnecting the standby oil path to supply hydraulic oil to the hydraulic execution element through the oil supply path;
step 908: receiving an operation stopping instruction, and controlling the second reversing valve to reverse so that the oil inlet valve port of the second reversing valve is communicated with the first execution valve port of the second reversing valve;
step 910: and under the condition that the hydraulic oil supplied by the hydraulic oil pump returns to the oil tank through the oil return valve port of the third reversing valve and the first execution valve port of the second reversing valve, the first reversing valve is controlled to be powered off.
In the technical scheme, a control mode of the hydraulic control system when the fire truck stops working is further provided, the oil inlet valve port of the second reversing valve is communicated with the first execution valve port of the second reversing valve, so that hydraulic oil in the hydraulic control system returns to the oil tank through the oil return valve port of the third reversing valve and the first execution valve port of the second reversing valve, the hydraulic oil pump can be prevented from being suppressed, and the safety, the stability and the practical service life of the fire truck are improved.
DETAILED DESCRIPTION OF EMBODIMENT (S) OF INVENTION
As shown in fig. 1, the present embodiment provides a hydraulic control system including: the hydraulic actuator 2; the hydraulic oil pump 4 is connected to the hydraulic execution element 2 through an oil supply path; the first reversing valve 6 is arranged on the oil supply path, the hydraulic oil pump 4 is communicated with an oil inlet valve port 602 of the first reversing valve, and the hydraulic actuating element 2 is communicated with an actuating valve port 604 of the first reversing valve; one end of the standby oil way is communicated with the oil supply way, the other end of the standby oil way is communicated with the oil tank 26, and the joint of the standby oil way and the oil supply way is positioned between the first reversing valve 6 and the hydraulic oil pump 4; the second reversing valve 8 is arranged on the standby oil path, the standby oil path is communicated with an oil inlet valve port 802 of the second reversing valve, and a first execution valve port 804 of the second reversing valve is communicated with the oil tank 26.
Further, the hydraulic oil pump 4 is a load-sensitive pump, an output end of the load-sensitive pump is communicated with the oil inlet valve port 602 of the first reversing valve through an oil supply path, and the load-sensitive port 402 of the load-sensitive pump is communicated with the oil return valve port 606 of the first reversing valve through a constant-pressure oil path; the second reversing valve 8 is arranged on the standby oil path and the constant-pressure oil path, the load sensing port 402 of the load sensing pump is communicated with the second execution valve port 806 of the second reversing valve, and the oil return valve port 808 of the second reversing valve is communicated with the oil return valve port 606 of the first reversing valve; under the condition of receiving the constant pressure operation command, the second direction valve 8 is reversed, so that the oil return port 808 of the second direction valve is connected to the second execution port.
Further, the hydraulic control system further includes: and a first orifice 10 is provided in the constant pressure oil path between the second directional control valve 8 and the load-sensitive port 402.
Further, the hydraulic control system further includes: a plurality of third directional control valves; the oil supply path includes: the hydraulic oil pump 4 is communicated with the main road; the branch circuits are communicated with the main circuit; the number of the hydraulic actuating elements 2 is multiple, each branch is correspondingly connected with one hydraulic actuating element 2 and one third reversing valve, an oil return valve port of each third reversing valve is communicated with the oil tank 26, an oil inlet valve port of each third reversing valve is communicated with the main path, and an actuating valve port of each third reversing valve is communicated with one hydraulic actuating element 2.
Further, the hydraulic control system further includes: and the second damping hole 12 is arranged on the oil waiting path and is positioned between the oil tank 26 and the second reversing valve 8.
Further, the hydraulic control system further includes: and the second check valve 14 is arranged on the oil supply path and is positioned between the joint of the standby oil path and the oil supply path and the hydraulic oil pump 4.
Further, the hydraulic control system further includes: and the radiator 16 is arranged on the oil waiting path and is positioned between the second reversing valve 8 and the oil tank 26.
Specifically, as shown in fig. 1, in a state where the first direction valve 6 is powered, the first direction valve 6 is in a left position, an oil inlet port 602 of the first direction valve is communicated with an actuating port 604 of the first direction valve, and in a state where the first direction valve 6 is powered off, the first direction valve 6 disconnects a passage between an oil supply passage and the hydraulic actuating element 2; when the second direction valve 8 is in a power-off state, the oil inlet port of the second direction valve 8 is communicated with the first execution valve port 804 of the second direction valve, and when the second direction valve 8 is in a power-on state, the oil return valve port 808 of the second direction valve is communicated with the second execution valve port.
In the hydraulic control system provided by the embodiment, when the system is in a standby state, the outlet of the load-sensitive pump passes through the second reversing valve 8 and the second damping hole 12, passes through the radiator 16 and then returns to the oil tank 26.
According to the hydraulic control system provided by the embodiment, when the hydraulic actuator 2 needs to be driven and a load needs to act, the first reversing valve 6 is powered firstly, and the second reversing valve 8 is powered in a delayed mode.
In the hydraulic control system provided by the embodiment, when the system stops, the second reversing valve 8 is powered off firstly, and the first reversing valve 6 is powered on firstly to be powered off in a delayed manner.
In the hydraulic control system provided by the embodiment, the second valve port of the second reversing valve 8 is connected with the second damping hole 12 in series and then is connected back to the load-sensitive pump port (LS port) of the load-sensitive pump.
In the hydraulic control system provided by the embodiment, when the system is in a standby state, the flow passing through the first valve port of the second control valve is only related to the sectional area of the second orifice 12, and the standby pressure is the spring force of the second check valve 14.
The hydraulic control system provided by the embodiment can be applied to a fire fighting truck, when a boom 20 or a landing leg 18 system of the fire fighting truck works, the first reversing valve 6 is powered on first, the flow of the hydraulic oil pump 4 returns to the oil return tank 26 from the third reversing valve of the boom 20 or the third reversing valve of the landing leg 18 of the first reversing valve 6, and meanwhile, the hydraulic oil pump can return to the oil return tank 26 through the first valve port of the second reversing valve 8 and the first damping hole 10; then the second reversing valve 8 is powered on in a delayed mode, the oil pressure passes through a second valve port of the second reversing valve 8 and an LS port of the hydraulic oil pump 4 through a second damping hole 12, and the hydraulic oil pump 4 is switched to a mode of a constant-pressure variable pump; due to the existence of the second damping hole 12, the instantaneous change of the discharge capacity of the hydraulic oil pump 4 is avoided, and the discharge capacity impact of the hydraulic oil pump 4 is reduced. In particular, the third directional valve may be a three-way flow valve.
When the hydraulic control system of the fire fighting truck stops working, the second reversing valve 8 is powered off first, the flow of the hydraulic oil pump 4 flows from the first reversing valve 6 to the oil tank 26 through the third reversing valve of the boom 20 or the supporting leg 18, and can simultaneously flow back to the oil tank 26 through the first valve port of the second reversing valve 8 and the first damping hole 10; the first reversing valve 6 is powered off in a delayed mode, and the hydraulic oil pump 4 is prevented from being pressed.
The hydraulic control system provided by the embodiment has the following beneficial effects:
1. and a control mode of a two-point pump can be realized by adopting a common load sensitive pump.
2. The medium and small flow output is realized during low-speed and high-speed standby, and the oil can be returned through the radiator 16 for heat dissipation, so that the problem that the hydraulic oil temperature is high when the hydraulic oil pump is in high-speed standby due to continuous long-time water pumping of the fire truck is avoided.
3. Performance: the control strategy is improved, hardware and software are combined, standby flow is ready at any time, the response speed of the system is improved, and the pressure impact of reversing of the reversing valve is reduced.
4. The displacement of the hydraulic oil pump 4 has no impact when starting and stopping.
In the present invention, the terms "mounting", "connecting", "fixing" and the like are used in a broad sense, for example, "connecting" may be a fixed connection, a detachable connection, or an integral connection; "coupled" may be direct or indirect through an intermediary. The specific meaning of the above terms in the present invention can be understood according to specific situations by those skilled in the art.
In the description of the present specification, the description of the terms "one embodiment," "some embodiments," "specific embodiments," etc., means 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 invention. In this specification, the schematic representations of the terms used above 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 description is only a preferred embodiment of the present invention and is not intended to limit the present invention, and various modifications and changes may be made by those skilled in the art. Any modification, equivalent replacement, or improvement made within the spirit and principle of the present invention should be included in the protection scope of the present invention.
Claims (10)
1. A hydraulic control system, comprising:
a hydraulic actuator;
the hydraulic oil pump is connected to the hydraulic execution element through an oil supply path;
the first reversing valve is arranged on the oil supply path and is positioned between the hydraulic oil pump and the hydraulic actuating element;
one end of the standby oil way is communicated with the oil supply way, the other end of the standby oil way is communicated with an oil tank, and the joint of the standby oil way and the oil supply way is positioned between the first reversing valve and the hydraulic oil pump;
and the second reversing valve is arranged on the oil waiting path.
2. The hydraulic control system of claim 1,
the oil inlet valve port of the first reversing valve is communicated with the hydraulic oil pump, and the execution valve port of the first reversing valve is communicated with the hydraulic execution element;
an oil inlet valve port of the second reversing valve is communicated with the standby oil way, and a first execution valve port of the second reversing valve is communicated with the oil tank;
the hydraulic oil pump is a load-sensitive pump, the output end of the load-sensitive pump is communicated with the oil inlet valve port of the first reversing valve through the oil supply path, and the load-sensitive port of the load-sensitive pump is communicated with the oil return valve port of the first reversing valve through a constant-pressure oil path;
the second reversing valve is arranged on the standby oil way and the constant-pressure oil way, a load sensitive port of the load sensitive pump is communicated with a second execution valve port of the second reversing valve, and an oil return valve port of the second reversing valve is communicated with an oil return valve port of the first reversing valve.
3. The hydraulic control system of claim 2, further comprising:
and the first damping hole is arranged on the constant-pressure oil path and is positioned between the second reversing valve and the load sensitive port.
4. The hydraulic control system of claim 3, further comprising:
the first check valve is positioned on the constant-pressure oil way, the communication position of an oil inlet valve port of the first check valve and the constant-pressure oil way is positioned between the first damping hole and the load sensitive port, and the communication position of an oil outlet valve port of the first check valve and the constant-pressure oil way is positioned between the first damping hole and the second execution valve port of the second reversing valve.
5. The hydraulic control system of claim 1, further comprising:
a plurality of third directional control valves;
the oil supply path includes:
the hydraulic oil pump is communicated with the main road;
a plurality of branches connected to the main path;
the hydraulic actuating elements are multiple in number, each branch is correspondingly connected with one or more hydraulic actuating elements and one third reversing valve, an oil return valve port of each third reversing valve is communicated with the oil tank, an oil inlet valve port of each third reversing valve is communicated with the main path, and each actuating valve port of each third reversing valve is communicated with one hydraulic actuating element.
6. The hydraulic control system according to any one of claims 1 to 5, characterized by further comprising:
and the second damping hole is arranged on the oil waiting path and is positioned between the oil tank and the second reversing valve.
7. The hydraulic control system according to any one of claims 1 to 5, characterized by further comprising:
and the second one-way valve is arranged on the oil supply path and positioned between the joint of the standby oil path and the oil supply path and the hydraulic oil pump, and an oil inlet valve port of the second one-way valve is communicated with the hydraulic oil pump.
8. The hydraulic control system according to any one of claims 1 to 5, characterized by further comprising:
and the radiator is arranged on the oil waiting path and is positioned between the second reversing valve and the oil tank.
9. A fire engine, comprising a chassis, comprising:
the supporting legs are arranged on the chassis;
the arm support is arranged on the chassis;
the hydraulic control system as claimed in any one of claims 1 to 8, wherein hydraulic actuators of the hydraulic control system are connected to the support legs and the arm support for driving the arm support and the support legs to extend or retract.
10. The fire engine of claim 9, wherein the hydraulic actuator comprises:
the supporting leg oil cylinder is connected to the supporting leg and used for driving the supporting leg to extend or retract;
the arm support oil cylinder is connected to the arm support and used for driving the arm support to extend out or retract.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202021578525.0U CN212455013U (en) | 2020-08-03 | 2020-08-03 | Hydraulic control system and fire engine |
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| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202021578525.0U CN212455013U (en) | 2020-08-03 | 2020-08-03 | Hydraulic control system and fire engine |
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| CN212455013U true CN212455013U (en) | 2021-02-02 |
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| CN (1) | CN212455013U (en) |
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2020
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