CN108547810B - Hydraulic control system of energy-saving grain combine harvester - Google Patents
Hydraulic control system of energy-saving grain combine harvester Download PDFInfo
- Publication number
- CN108547810B CN108547810B CN201810799587.5A CN201810799587A CN108547810B CN 108547810 B CN108547810 B CN 108547810B CN 201810799587 A CN201810799587 A CN 201810799587A CN 108547810 B CN108547810 B CN 108547810B
- Authority
- CN
- China
- Prior art keywords
- oil
- valve
- way
- communicated
- main
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Active
Links
- 230000002265 prevention Effects 0.000 claims abstract description 52
- 230000002457 bidirectional effect Effects 0.000 claims abstract description 22
- 238000006073 displacement reaction Methods 0.000 claims description 5
- 230000000630 rising effect Effects 0.000 claims description 2
- 238000005265 energy consumption Methods 0.000 abstract description 5
- 238000000034 method Methods 0.000 abstract description 5
- 230000008569 process Effects 0.000 abstract description 4
- 239000012535 impurity Substances 0.000 description 5
- 230000009471 action Effects 0.000 description 4
- 230000001105 regulatory effect Effects 0.000 description 4
- 230000001174 ascending effect Effects 0.000 description 3
- 238000004891 communication Methods 0.000 description 3
- 230000001276 controlling effect Effects 0.000 description 2
- 238000010586 diagram Methods 0.000 description 2
- 238000005299 abrasion Methods 0.000 description 1
- 230000006978 adaptation Effects 0.000 description 1
- 230000009286 beneficial effect Effects 0.000 description 1
- 230000004069 differentiation Effects 0.000 description 1
- 238000011065 in-situ storage Methods 0.000 description 1
- 238000012986 modification Methods 0.000 description 1
- 230000004048 modification Effects 0.000 description 1
- 230000007935 neutral effect Effects 0.000 description 1
- 239000002245 particle Substances 0.000 description 1
Classifications
-
- F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
- F15—FLUID-PRESSURE ACTUATORS; HYDRAULICS OR PNEUMATICS IN GENERAL
- F15B—SYSTEMS ACTING BY MEANS OF FLUIDS IN GENERAL; FLUID-PRESSURE ACTUATORS, e.g. SERVOMOTORS; DETAILS OF FLUID-PRESSURE SYSTEMS, NOT OTHERWISE PROVIDED FOR
- F15B11/00—Servomotor systems without provision for follow-up action; Circuits therefor
- F15B11/08—Servomotor systems without provision for follow-up action; Circuits therefor with only one servomotor
-
- F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
- F15—FLUID-PRESSURE ACTUATORS; HYDRAULICS OR PNEUMATICS IN GENERAL
- F15B—SYSTEMS ACTING BY MEANS OF FLUIDS IN GENERAL; FLUID-PRESSURE ACTUATORS, e.g. SERVOMOTORS; DETAILS OF FLUID-PRESSURE SYSTEMS, NOT OTHERWISE PROVIDED FOR
- F15B13/00—Details of servomotor systems ; Valves for servomotor systems
- F15B13/02—Fluid distribution or supply devices characterised by their adaptation to the control of servomotors
- F15B13/024—Pressure relief valves
-
- F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
- F15—FLUID-PRESSURE ACTUATORS; HYDRAULICS OR PNEUMATICS IN GENERAL
- F15B—SYSTEMS ACTING BY MEANS OF FLUIDS IN GENERAL; FLUID-PRESSURE ACTUATORS, e.g. SERVOMOTORS; DETAILS OF FLUID-PRESSURE SYSTEMS, NOT OTHERWISE PROVIDED FOR
- F15B21/00—Common features of fluid actuator systems; Fluid-pressure actuator systems or details thereof, not covered by any other group of this subclass
- F15B21/04—Special measures taken in connection with the properties of the fluid
- F15B21/041—Removal or measurement of solid or liquid contamination, e.g. filtering
Abstract
The invention discloses a hydraulic control system of an energy-saving grain combine harvester, which comprises: the hydraulic device is capable of respectively conveying pressure oil to the full hydraulic steering device and the reel oil cylinder through the priority valve; the first valve group comprises a first reversing valve and a bidirectional backflow prevention valve, an oil inlet of the first reversing valve is communicated with a main oil way of the executive component, an oil return port of the first reversing valve is communicated with the main oil way through a first oil drain way, an oil through port of the first reversing valve is communicated with a first oil port of the bidirectional backflow prevention valve, and a second oil port of the bidirectional backflow prevention valve is communicated with the reel oil cylinder; and an oil way between the oil through hole of the first reversing valve and the first oil hole of the bidirectional backflow preventing valve is led out to form a first control oil way, and the first control oil way is communicated with the adjustable hydraulic device through an LS oil way. The invention enables the pressure and flow provided by the hydraulic device to be matched with the load of the grain combine harvester, reduces the energy loss in the operation process and saves the energy consumption.
Description
Technical Field
The invention relates to the technical field of hydraulic control processes of agricultural machinery, in particular to a hydraulic control system of an energy-saving grain combine harvester.
Background
The grain combine harvester is used as a high-power agricultural machine, and has the disadvantages of severe working environment, complex working procedures and numerous and miscellaneous executing elements. In the actual operation process, the load is changed frequently, so that the pressure and the flow required by the whole hydraulic system are changed continuously, and the overflow and throttling losses are serious. The design of the traditional harvester hydraulic system mainly considers the working capacity, reliability and cost of the system, does not pay attention to the efficiency of the hydraulic system, and the efficiency of the hydraulic system is about 50% mostly, so that the hydraulic energy loss is overlarge.
The main reason for energy loss of the hydraulic system of the harvester is as follows: the pressure and flow provided by the hydraulic device are not matched with the load of the grain combine harvester, and are often larger than the actual requirement of the load, so that the excessive hydraulic energy is lost in the form of throttling and overflow, the outlet pressure of the hydraulic device is often fluctuated with the load, and therefore, the pressure and flow provided by the hydraulic device are matched with the load, and the main way for saving energy consumption is realized.
Disclosure of Invention
The invention aims to provide an energy-saving hydraulic control system of a grain combine harvester, which enables the pressure and flow provided by a hydraulic device to be matched with the load of the grain combine harvester, reduces energy loss in the operation process and saves energy consumption.
The technical scheme provided by the invention is as follows:
a hydraulic control system for an energy efficient grain combine harvester, comprising: the full-hydraulic steering device is communicated with the steering oil cylinder and controls the piston of the steering oil cylinder to move; the hydraulic device comprises an adjustable hydraulic device and a priority valve, wherein the adjustable hydraulic device is communicated with an oil inlet of the priority valve through a main pump oil way, a first oil outlet of the priority valve is communicated with a full hydraulic steering gear through a steering gear main oil way, a second oil outlet of the priority valve is communicated with a reel oil cylinder through an execution element main oil way, and the adjustable hydraulic device respectively conveys pressure oil to the full hydraulic steering gear and the reel oil cylinder through the priority valve; when the priority valve is in a first state, an oil inlet of the priority valve is communicated with a first oil outlet, an oil inlet of the priority valve is disconnected with a second oil outlet, and the adjustable hydraulic device is communicated with the full-hydraulic steering gear through the priority valve and is used for driving the steering oil cylinder; when the priority valve is in a second state, an oil inlet of the priority valve is communicated with a second oil outlet, the oil inlet of the priority valve is disconnected with a first oil outlet, and the adjustable hydraulic device is communicated with the first valve group and the reel oil cylinder through the priority valve to drive the reel oil cylinder; the first valve group comprises a first reversing valve and a bidirectional backflow prevention valve which are sequentially communicated, an oil inlet of the first reversing valve is communicated with a main oil way of the executive component through a first main oil way, an oil return port of the first reversing valve is communicated with the main oil drain way through a first oil drain way, an oil port of the first reversing valve is communicated with a first oil port of the bidirectional backflow prevention valve, and a second oil port of the bidirectional backflow prevention valve is communicated with a reel oil cylinder; a first control oil way is led out from an oil way between the oil through hole of the first reversing valve and the first oil hole of the bidirectional backflow preventing valve, and is communicated with the adjustable hydraulic device through an LS oil way and used for feeding back the load pressure of the reel oil cylinder to the adjustable hydraulic device through the first control oil way and the LS oil way in sequence; when the reel cylinder is in a rising state, an oil inlet of the first reversing valve is communicated with an oil through port, the oil through port of the first reversing valve is disconnected with an oil return port, and the first reversing valve conveys pressure oil conveyed by the priority valve to the bidirectional backflow prevention valve; when the reel oil cylinder is in a descending state, an oil inlet of the first reversing valve is disconnected from an oil through hole, the oil through hole of the first reversing valve is communicated with an oil return hole, and the first reversing valve discharges pressure oil conveyed by the bidirectional backflow prevention valve back to the oil tank through a first oil drain oil path.
In the structure, the LS oil way is adopted to feed back the load pressure to the adjustable hydraulic device in real time, and the adjustable hydraulic device adjusts the pressure and the flow of the pressure oil to be output in real time through the feedback pressure of the LS oil way, so that the output pressure and the flow of the adjustable hydraulic device are matched with the actual load, the loss of hydraulic energy is reduced, the efficiency of a hydraulic control system is improved, and the energy consumption is saved. The priority valve enables the steering oil cylinder and the executing element not to work simultaneously, and the steering action is preferentially ensured, namely when the priority valve conveys the pressure oil to the steering oil cylinder, the priority valve can not convey the pressure oil to the executing element, and the safety of the harvester during steering is ensured.
Preferably, the adjustable hydraulic device comprises a constant displacement pump and a pilot logic valve, wherein an oil outlet of the constant displacement pump is respectively communicated with an oil inlet of the pilot logic valve and an oil inlet of the priority valve; the control oil port of the pilot logic valve is used for receiving feedback pressure of the LS oil path and controlling flow of pressure oil quantitatively pumped back to the oil tank through the feedback pressure; or the adjustable hydraulic device is a load-sensitive variable pump, a control oil port of the load-sensitive variable pump is communicated with the LS oil circuit, and the load-sensitive variable pump receives feedback pressure of the LS oil circuit to adjust pressure and flow of an oil outlet of the load-sensitive variable pump.
Preferably, the LS oil way is provided with a first throttling hole; a second throttling hole is arranged on the first main oil way; a third throttling hole is arranged on the first oil drain oil way; and a control oil way one-way valve is arranged on the first control oil way.
The first orifice is used for regulating the feedback pressure in the LS oil way within a pressure range to be safe, and the second orifice and the third orifice are used for regulating the flow rate of pressure oil, so that the purpose of regulating the action speed of the reel oil cylinder is achieved. The control oil way check valve enables pressure oil to flow to the LS oil way only through the first control oil way and not flow reversely.
Preferably, the hydraulic control system of the energy-saving grain combine harvester further comprises: the second valve group comprises a first one-way backflow prevention valve, a second one-way backflow prevention valve, a third one-way backflow prevention valve, a main oil way one-way valve, a first adjustable throttle valve and a pressure reducing valve; the second one-way backflow prevention valve, the first adjustable throttle valve and the main oil way check valve are sequentially communicated to form a header oil supply oil way, an oil inlet of the second one-way backflow prevention valve is communicated with the main oil way of the executing element through a second main oil way, an oil outlet of the main oil way check valve is respectively communicated with an oil port of a header oil cylinder and an oil port of an energy accumulator, and the LS oil way is communicated with an oil way for connecting the first adjustable throttle valve and the main oil way check valve through a second control oil way; the oil outlet of the pressure reducing valve is communicated with the main oil drain way through a second oil drain way, and the oil inlet of the third one-way backflow preventing valve is respectively communicated with the oil port of the header oil cylinder and the oil port of the energy accumulator; an oil inlet of the first one-way backflow prevention valve is communicated with an oil inlet of the second one-way backflow prevention valve, and an oil outlet of the first one-way backflow prevention valve is communicated with the second oil drain way.
In the structure, the header oil cylinder and the energy accumulator are connected through the second valve group, so that the adjustable hydraulic device can supply oil to the header oil cylinder and the energy accumulator at the same time, wherein the adjustable throttle valve can adjust the ascending speed of the header according to the weight of different headers, and the pressure reducing valve is used for adjusting the descending speed according to the weight of different headers. The main oil way check valve is used for avoiding backflow of pressure oil conveyed into the header oil cylinder, plays a role in maintaining pressure of the header oil cylinder and the energy accumulator, and avoids leakage of the pressure oil in the header oil cylinder and the energy accumulator.
Preferably, the second valve group further comprises a normally closed logic valve, an oil inlet of the normally closed logic valve is communicated with an oil outlet of the second one-way backflow prevention valve, and an oil outlet of the normally closed logic valve is communicated with the second oil drain path; the first comparison oil way of the normally closed logic valve is communicated with an oil inlet of the first adjustable throttle valve, and the second comparison oil way of the normally closed logic valve is communicated with an oil way for connecting the first adjustable throttle valve and the main oil way check valve; when the oil pressure of the first comparison oil way is larger than the sum of the oil pressure of the second comparison oil way and the spring force of the normally closed logic valve, the normally closed logic valve is in an open state, and the pressure oil in the main oil way of the executive element flows back to the oil tank through the second unidirectional backflow prevention valve, the normally closed logic valve, the second oil drain oil way and the main oil drain oil way in sequence.
In the structure, by arranging the normally closed logic valve, when the oil pressure of the first comparison oil way is detected to be larger than the sum of the oil pressure of the second comparison oil way and the spring force of the normally closed logic valve, the pressure of the pressure oil input into the header oil supply oil way is indicated to be overlarge, and at the moment, the normally closed logic valve is opened to enable the redundant pressure oil to flow back to the oil tank through the second oil drain oil way and the main oil drain oil way.
Preferably, the hydraulic control system of the energy-saving grain combine harvester further comprises: the third valve group comprises a second reversing valve and a hydraulic lock which are sequentially communicated, and the second reversing valve is a three-position five-way electromagnetic valve; the oil inlet of the second reversing valve and the second oil outlet of the priority valve are communicated with a third main oil way sequentially through an execution element main oil way, and a fourth orifice is arranged at the third main oil way; the control oil port of the second reversing valve is communicated with the LS oil circuit through a third control oil circuit, a one-way valve is arranged at the third control oil circuit, and pressure oil flows to the LS oil circuit through the one-way valve; the oil return port of the second reversing valve is communicated with the main oil drain way through a third oil drain way; and the pressure oil drives the double-acting oil cylinder through the second reversing valve and the hydraulic lock in sequence.
In the above structure, by providing the third valve group, the adjustable hydraulic device is a double-acting cylinder, for example: the grain unloading oil cylinder, the main clutch oil cylinder or the gap bridge clutch oil cylinder supplies oil. And the reciprocating motion of the piston in the double-acting oil cylinder is realized through the cooperation between the second reversing valve and the hydraulic lock. The third control oil path is provided with a control oil path one-way valve to prevent pressure oil from flowing back to the second reversing valve, and the fourth throttle hole is used for adjusting the flow of the pressure oil transmitted into the double-acting oil cylinder, so that the movement speed of the piston of the double-acting oil cylinder is controlled.
Preferably, the main oil drainage path is provided with an oil return filter; and/or two oil filters are arranged on the main pump oil way, and the adjustable hydraulic device is positioned between the two oil filters.
The oil return filter can filter out particle impurities, rubber impurities and the like generated by abrasion and the like of the operation of the execution element, and avoids the impurities from being doped in the pressure oil and being brought into the oil return tank. The oil filter is arranged, so that impurities of the pressure oil in the oil tank can be prevented from entering the adjustable hydraulic device, and the adjustable hydraulic device is damaged, so that the service life of the adjustable hydraulic device is shortened. And meanwhile, impurities are prevented from being pumped into a subsequent actuating element or a steering cylinder, so that the steering cylinder or the actuating element is prevented from being damaged.
Preferably, the LS oil passage is connected in parallel with a control safety oil passage, and the control safety oil passage is provided with a control oil passage safety valve for detecting the oil pressure of the LS oil passage.
In the structure, the control oil way safety valve is arranged, so that the oil pressure of the pressure oil in the LS oil way can be detected, and the pressure of the pressure oil in the LS oil way is ensured to be within a safety range.
Preferably, a fifth orifice is further arranged on the control safety oil path.
In the above structure, the fifth orifice is to return the excess pressure oil in the LS oil passage to the tank while maintaining the pressure required for feedback on the LS oil passage.
Preferably, the main drain oil passage and the main pump oil passage are communicated with each other through a main oil passage relief valve for detecting the oil pressure of the main pump oil passage.
In the structure, the main oil way safety valve is arranged, so that the oil pressure of the pressure oil of the whole hydraulic control system can be monitored, and the pressure of the pressure oil of the hydraulic control system is ensured to be within a safety range.
The hydraulic control system of the energy-saving grain combine harvester provided by the invention has the following beneficial effects:
the invention provides a hydraulic control system applied to a combine harvester, which is characterized in that a priority valve is arranged to ensure priority execution of steering actions, feedback pressure of an adjustable hydraulic device is fed back to an LS oil circuit, and the adjustable hydraulic device adjusts flow and pressure of output pressure oil through the feedback pressure to be matched with the load of the real-time combine harvester, so that hydraulic energy loss of the hydraulic control system in a throttling or overflow mode is reduced, efficiency of the hydraulic control system is improved, and energy consumption is saved.
Drawings
The above-mentioned features, technical features, advantages and implementation of the hydraulic control system of the energy-saving grain combine harvester will be further described in a clear and understandable manner with reference to the accompanying drawings.
FIG. 1 is a hydraulic schematic diagram of one embodiment of a hydraulic control system of an energy efficient grain combine of the present invention;
FIG. 2 is a hydraulic schematic diagram of another embodiment of the hydraulic control system of the energy efficient grain combine of the present invention;
fig. 3 is a schematic structural view of the second reversing valve.
Reference numerals illustrate:
1-steering cylinder, 2 a-constant delivery pump, 2B-load sensitive variable pump, 3-pilot logic valve, 4-full hydraulic steering gear, 5-oil tank, 6-priority valve, 7-main oil path safety valve, 8-control oil path safety valve, 9-first throttle hole, 10-second throttle hole, 11-first reversing valve, 12-two-way backflow prevention valve, 13-third throttle hole, 14-reel cylinder, 15-grain unloading cylinder, 16-main clutch cylinder, 17-bridge-crossing clutch cylinder, 18-header cylinder, 19-accumulator, 20-return oil filter, 21-first one-way backflow prevention valve, 22-second one-way backflow prevention valve, 23-first adjustable throttle valve, 24-main oil path one-way valve, 25-third one-way backflow prevention valve, 26-relief valve, 27-normally closed logic valve, 28-fourth orifice, 29-second reversing valve, 29 a-left position of second reversing valve, 29B-middle position of second reversing valve, 29C-right position of second reversing valve, 30-hydraulic lock, 31-oil filter, 32-control oil way check valve, 33-fifth orifice, 34-second adjustable throttle valve, 35-third adjustable throttle valve, A-main pump oil way, B-diverter main oil way, C-actuator main oil way, D-LS oil way, E-first main oil way, F-first oil drain oil way, G-header oil drain way, H-second oil drain way, I-third main oil way, J-third control oil way, K-third oil drain way, the device comprises an L-control safety oil way, an M-main oil drain oil way, an N-header oil supply oil way, an O-second main oil way and a P-first control oil way.
Detailed Description
In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the following description will explain the specific embodiments of the present invention with reference to the accompanying drawings. It is evident that the drawings in the following description are only examples of the invention, from which other drawings and other embodiments can be obtained by a person skilled in the art without inventive effort.
For simplicity of the drawing, only the parts relevant to the present invention are schematically shown in each drawing, and they do not represent the actual structure thereof as a product.
[ example 1 ]
As shown in fig. 1, embodiment 1 discloses a hydraulic control system of an energy-saving grain combine harvester, comprising: and the full hydraulic steering gear 4 is communicated with the steering oil cylinder 1, and the full hydraulic steering gear 4 controls the piston movement of the steering oil cylinder 1.
The hydraulic device is communicated with an oil inlet of the priority valve 6 through a main pump oil way A, a first oil outlet of the priority valve 6 is communicated with the full hydraulic steering gear 4 through a steering gear main oil way B, a second oil outlet of the priority valve 6 is communicated with the reel oil cylinder 14 through an actuating element main oil way C, and the hydraulic device respectively conveys pressure oil to the full hydraulic steering gear 4 and the reel oil cylinder 14 through the priority valve 6.
The priority valve 6 has two communication states, as follows:
when the priority valve 6 is in the first state, the oil inlet of the priority valve 6 is communicated with the first oil outlet, the oil inlet of the priority valve 6 is disconnected from the second oil outlet, and the adjustable hydraulic device is communicated with the full-hydraulic steering gear 4 through the priority valve 6 and is used for driving the steering oil cylinder 1.
When the priority valve 6 is in the second state, the oil inlet of the priority valve 6 is communicated with the second oil outlet, the oil inlet of the priority valve 6 is disconnected with the first oil outlet, and the adjustable hydraulic device is communicated with the first valve group and the reel oil cylinder 14 through the priority valve 6 and is used for driving the reel oil cylinder 14.
The aforementioned first valve group includes: the first reversing valve 11 and the two-way backflow prevention valve 12 which are communicated in sequence, an oil inlet of the first reversing valve 11 and the main oil way C of the executive component are communicated through the first main oil way E, an oil return port of the first reversing valve 11 is communicated with the main oil drain way M through the first oil drain way F, an oil through port of the first reversing valve 11 is communicated with a first oil port of the two-way backflow prevention valve 12, and a second oil port of the two-way backflow prevention valve 12 is communicated with the reel oil cylinder 14.
Specifically, the two-way backflow prevention valve 12 has two states;
the right position is in a one-way valve state, namely, the pressure oil can only flow from the reel cylinder 14 to the first reversing valve 11.
The left position is in a state of two-way circulation, namely, the pressure oil can flow from the reel cylinder 14 towards the first reversing valve 11 or flow from the first reversing valve 11 towards the reel cylinder 14.
A first control oil path P is led out from an oil path between the oil port of the first reversing valve 11 and the first oil port of the bidirectional backflow preventing valve 12, and the first control oil path P is communicated with the adjustable hydraulic device through an LS oil path D and is used for feeding back the load pressure of the reel oil cylinder 14 to the adjustable hydraulic device through the first control oil path P and the LS oil path D in sequence.
In this embodiment, the adjustable hydraulic device includes a constant delivery pump 2a and a pilot logic valve 3, where an oil outlet of the constant delivery pump 2a is respectively communicated with oil inlets of the pilot logic valve 3 and a priority valve 6, and an LS oil path D is communicated with a control oil port of the pilot logic valve 3, where the control oil port of the pilot logic valve 3 is configured to receive a feedback pressure of the LS oil path D and control a flow rate of pressure oil that is returned to the oil tank 5 by the constant delivery pump 2a through the feedback pressure, so as to adjust a flow rate of pressure oil that is delivered to the steering cylinder 1 or the actuator through the priority valve 6.
The full hydraulic steering gear 4 in this embodiment may be a load-sensitive steering gear, where a load-sensitive oil port of the load-sensitive steering gear is connected to a control oil port of the pilot logic valve 3, and load pressure at the steering cylinder is directly fed back to the pilot logic valve 3 through the load-sensitive oil port. The steering pressure is controlled by a relief valve on the load-sensitive steering gear.
The specific working principle of the pilot logic valve 3 is as follows:
when the harvester is in an in-situ idle state or a straight running state, the oil pressure at the oil outlet of the constant delivery pump 2a flows into the pilot logic valve 3 through a pilot oil path on the right side of the pilot logic valve 3, the valve core of the pilot logic valve 3 is propped to the left end, at the moment, the pilot logic valve 3 is in the right position, the pressure oil at the oil outlet of the constant delivery pump 2a flows back into the oil tank 5 through the pilot logic valve 3, and in the state, the oil pressure in the pilot oil path is balanced with the spring force of the pilot logic valve 3.
When the steering cylinder 1 or the actuator of the harvester is operated, the LS oil path D receives corresponding feedback oil pressure and transmits the feedback oil pressure into the pilot logic valve 3 through the left end of the pilot logic valve 3, so that the valve core of the pilot logic valve 3 moves towards the right side for a certain distance, at the moment, the larger the feedback oil pressure of the LS oil path D is, the larger the distance the valve core moves rightwards is, the smaller the unit time flow rate of the pilot logic valve 3 is, the smaller the pressure oil quantity of the constant delivery pump 2a flowing back to the oil tank 5 through the pilot logic valve 3 is, and the output oil pressure and the displacement of the adjustable hydraulic device are matched with the load.
The LS oil path D is provided with a first orifice 9 for regulating the feedback pressure in the LS oil path D within a pressure range to be safe. The first main oil way E is provided with a second throttle hole 10, the first oil drain oil way F is provided with a third throttle hole 13, and the second throttle hole 10 and the third throttle hole 13 are used for adjusting the flow rate of pressure oil, so that the purpose of adjusting the action speed of the reel oil cylinder 14 is achieved. The first control oil path P is provided with a control oil path check valve 32, and the control oil path check valve 32 enables pressure oil to flow to the LS oil path D only through the first control oil path P and not to flow reversely.
The flow direction of the pressure oil and the communication state of each valve of the first valve group when the reel cylinder 14 performs the ascending and descending operations are described below:
when the reel cylinder 14 is in an ascending state, an oil inlet of the first reversing valve 11 is communicated with an oil through port, the oil through port of the first reversing valve 11 is disconnected from an oil return port, the first reversing valve 11 conveys pressure oil conveyed by the priority valve 6 to the bidirectional backflow preventing valve 12, the bidirectional backflow preventing valve 12 is positioned at the left position at the moment, and the pressure oil is conveyed into the reel cylinder 14 through the bidirectional backflow preventing valve 12.
When the reel cylinder 14 is in a descending state, the bidirectional backflow prevention valve 12 is positioned at the right position, pressure oil flows into the oil through port of the first reversing valve 11 from the reel cylinder 14 through the bidirectional backflow prevention valve 12, at the moment, the oil inlet of the first reversing valve 11 is disconnected from the oil through port, the oil through port of the first reversing valve 11 is communicated with the oil return port, the pressure oil enters the first oil drain path F from the oil return port, and then is drained back to the oil tank 5 through the main oil drain path M.
[ example 2 ]
As shown in fig. 1, embodiment 2 is based on embodiment 1, and embodiment 2 further includes a second valve group.
The second valve group includes a first one-way backflow preventing valve 21, a second one-way backflow preventing valve 22, a third one-way backflow preventing valve 25, a main oil passage one-way valve 24, a first adjustable throttle valve 23, and a pressure reducing valve 26. The second one-way backflow prevention valve 22, the first adjustable throttle valve 23 and the main oil way check valve 24 are sequentially communicated to form a header oil supply oil way N, an oil inlet of the second one-way backflow prevention valve 22 is communicated with the main oil way C of the executing element through a second main oil way O, an oil outlet of the main oil way check valve 24 is respectively communicated with an oil port of the header oil cylinder 18 and an oil port of the accumulator 19, and is used for respectively conveying pressure to the header oil cylinder 18 and the accumulator 19, and an LS oil way D is communicated with an oil way for connecting the first adjustable throttle valve 23 and the main oil way check valve 24 through a second control oil way. More preferably, the accumulator 19 communicates with the outlet of the main circuit check valve 24 through a third adjustable throttle valve 35, the third adjustable throttle valve 35 being used to regulate the flow of pressurized oil delivered into the accumulator 19.
The third one-way backflow prevention valve 25 and the pressure reducing valve 26 are sequentially communicated to form a cutting table oil drain path G, an oil outlet of the pressure reducing valve 26 and the main oil drain path M are communicated through a second oil drain path H, and an oil inlet of the third one-way backflow prevention valve 25 is respectively communicated with an oil port of the cutting table oil cylinder 18 and an oil port of the energy accumulator 19. More preferably, the oil outlet of the relief valve 26 communicates with the second drain passage H through a second adjustable throttle 34.
The oil inlet of the first one-way backflow prevention valve 21 is communicated with the oil inlet of the second one-way backflow prevention valve 22, and the oil outlet of the first one-way backflow prevention valve 21 is communicated with the second oil drain path H.
[ example 3 ]
As shown in fig. 1, embodiment 3 the second valve group of embodiment 3 further includes a normally closed logic valve 27 on the basis of embodiment 2, an oil inlet of the normally closed logic valve 27 is communicated with an oil outlet of the second one-way backflow prevention valve 22, and an oil outlet of the normally closed logic valve 27 is communicated with the second drain oil path H.
The first comparison oil passage of the normally closed logic valve 27 communicates with the oil inlet of the first adjustable throttle valve 23, and the second comparison oil passage of the normally closed logic valve 27 communicates with the oil passage for connecting the first adjustable throttle valve 23 and the main oil passage check valve 24.
When the oil pressure of the first comparison oil path is larger than the sum of the oil pressure of the second comparison oil path and the spring force of the normally closed logic valve 27, the normally closed logic valve 27 is in an open state, and the pressure oil in the actuator main oil path C flows back to the oil tank 5 through the second one-way backflow prevention valve 22, the normally closed logic valve 27, the second drain oil path H, and the main drain oil path M in order.
[ example 4 ]
As shown in fig. 1, embodiment 4 is based on embodiments 1 to 3, embodiment 4 further includes a third valve group, the third valve group includes a second reversing valve 29 and a hydraulic lock 30 that are sequentially communicated, the second reversing valve 29 is a three-position five-way solenoid valve, an oil inlet of the second reversing valve 29 and a second oil outlet of the priority valve 6 are sequentially communicated with a third main oil path I through an actuator main oil path C, and a fourth orifice 28 is disposed at the third main oil path I.
The control oil port of the second reversing valve 29 is communicated with the LS oil path D through a third control oil path J, a one-way valve is arranged at the third control oil path J, pressure oil flows to the LS oil path D through the one-way valve, and the oil return port of the second reversing valve 29 is communicated with the main oil drain path M through a third oil drain path K. The pressure oil drives the double-acting cylinder through the second reversing valve 29 and the hydraulic lock 30 in sequence. The double acting cylinders may be a grain unloading cylinder 15, a main clutch cylinder 16 and a bridge clutch cylinder 17.
Specifically, the second reversing valve 29 has three positions, namely, a left position 29a, a middle position 29b and a right position 29c, and the specific communication manner is shown in fig. 3.
In this embodiment, the third valve group is three groups, and the corresponding double-acting cylinders are respectively a grain unloading cylinder 15, a main clutch cylinder 16 and a gap bridge clutch cylinder 17. When the double acting cylinder is not moving, the second reversing valve 29 is in the neutral position 29b.
When the double-acting oil cylinder extends outwards, the second reversing valve 29 is positioned at the left position 29a, pressure oil enters from the oil inlet, a part of the pressure oil enters into the third control oil path J through the control oil port, and then the load pressure corresponding to the double-acting oil cylinder is transmitted to the adjustable hydraulic device through the third control oil path J and the LS oil path D. Most of the pressure oil is introduced into the left oil port of the hydraulic lock 30, and then a small part of the pressure pushes the check valve on the right side of the hydraulic lock 30 open, so that the pressure oil in the space on the right side of the double-acting oil cylinder flows into the second reversing valve 29 through the check valve on the right side of the hydraulic lock 30, and enters the third oil drain passage K and the main oil drain passage M through the second reversing valve 29 to return to the oil tank 5. Most of the pressure oil in the hydraulic lock 30 pushes the one-way valve on the left side of the hydraulic lock 30 open, so that the pressure oil enters the left space of the double-acting oil cylinder, and the extension of the double-acting oil cylinder is realized.
When the double-acting oil cylinder is retracted inwards, the second reversing valve 29 is positioned at the right position 29c, pressure oil enters from the oil inlet, a part of the pressure oil enters into the third control oil path J through the control oil port, and then the load pressure corresponding to the double-acting oil cylinder is transmitted to the adjustable hydraulic device through the third control oil path J and the LS oil path D. Most of the pressure oil is introduced into the right oil port of the hydraulic lock 30, and then a small part of the pressure pushes the one-way valve at the left side of the hydraulic lock 30 open, so that the pressure oil in the left space of the double-acting oil cylinder flows into the second reversing valve 29 through the one-way valve at the left side of the hydraulic lock 30, and enters the third oil drain passage K and the main oil drain passage M through the second reversing valve 29 to return to the oil tank 5. Most of the pressure oil in the hydraulic lock 30 pushes the check valve on the right side of the hydraulic lock 30 open, so that the pressure oil enters the right space of the double-acting oil cylinder to retract the double-acting oil cylinder.
[ example 5 ]
As shown in fig. 1, in example 5, an oil return filter 20 is provided in the main drain passage M of example 5, an LS passage D is connected in parallel with a control relief passage L, and a control passage relief valve 8 for detecting the oil pressure of the LS passage D is provided in the control relief passage L, based on examples 1 to 4. The control relief oil passage L is further provided with a fifth orifice 33. The main drain oil passage M communicates with the main pump oil passage a through a main oil passage relief valve 7 for detecting the oil pressure of the main pump oil passage a. Two oil filters 31 are arranged on the main pump oil way A, and the adjustable hydraulic device is positioned between the two oil filters 31.
The control oil passage relief valve 8 is used to detect the oil pressure of the LS oil passage D so as to be within a relief pressure range. The main oil way safety valve 7 is used for detecting the oil pressure of the hydraulic control system, so that the hydraulic control system is protected from damage caused by pressure overload within a safety pressure range.
[ example 6 ]
As shown in fig. 2, the structure of embodiment 6 is basically the same as that of embodiments 1 to 5, and the difference of embodiment 6 is that the adjustable hydraulic device of embodiment 6 is a load-sensitive variable pump 2b, a control oil port of the load-sensitive variable pump 2b is communicated with an LS oil path D, and the load-sensitive variable pump 2b receives the feedback pressure of the LS oil path D to adjust the pressure and flow of an oil outlet.
It should be noted that the present invention may implement the differentiation of the load pressure of the respective actuators by the adjustable hydraulic device by controlling the throttle ratios of the first orifice 9, the second orifice 10, the fourth orifice 28, and the first adjustable throttle valve 23, and the throttle ratio of the specific design is determined according to the actual situation, which is not limited herein.
It should be noted that the above embodiments can be freely combined as needed. The foregoing is merely a preferred embodiment of the present invention and it should be noted that modifications and adaptations to those skilled in the art may be made without departing from the principles of the present invention, which are intended to be comprehended within the scope of the present invention.
Claims (10)
1. A hydraulic control system for an energy efficient grain combine harvester, comprising:
the full-hydraulic steering device is communicated with the steering oil cylinder and controls the piston of the steering oil cylinder to move;
the hydraulic device comprises an adjustable hydraulic device and a priority valve, wherein the adjustable hydraulic device is communicated with an oil inlet of the priority valve through a main pump oil way, a first oil outlet of the priority valve is communicated with a full hydraulic steering gear through a steering gear main oil way, a second oil outlet of the priority valve is communicated with a reel oil cylinder through an execution element main oil way, and the adjustable hydraulic device respectively conveys pressure oil to the full hydraulic steering gear and the reel oil cylinder through the priority valve;
when the priority valve is in a first state, an oil inlet of the priority valve is communicated with a first oil outlet, an oil inlet of the priority valve is disconnected with a second oil outlet, and the adjustable hydraulic device is communicated with the full-hydraulic steering gear through the priority valve and is used for driving the steering oil cylinder;
when the priority valve is in a second state, an oil inlet of the priority valve is communicated with a second oil outlet, the oil inlet of the priority valve is disconnected with a first oil outlet, and the adjustable hydraulic device is communicated with the first valve group and the reel oil cylinder through the priority valve to drive the reel oil cylinder;
the first valve group comprises a first reversing valve and a bidirectional backflow prevention valve which are sequentially communicated, an oil inlet of the first reversing valve is communicated with a main oil way of the executive component through a first main oil way, an oil return port of the first reversing valve is communicated with the main oil drain way through a first oil drain way, an oil port of the first reversing valve is communicated with a first oil port of the bidirectional backflow prevention valve, and a second oil port of the bidirectional backflow prevention valve is communicated with a reel oil cylinder;
a first control oil way is led out from an oil way between the oil through hole of the first reversing valve and the first oil hole of the bidirectional backflow preventing valve, and is communicated with the adjustable hydraulic device through an LS oil way and used for feeding back the load pressure of the reel oil cylinder to the adjustable hydraulic device through the first control oil way and the LS oil way in sequence;
when the reel cylinder is in a rising state, an oil inlet of the first reversing valve is communicated with an oil through port, the oil through port of the first reversing valve is disconnected with an oil return port, and the first reversing valve conveys pressure oil conveyed by the priority valve to the bidirectional backflow prevention valve;
when the reel oil cylinder is in a descending state, an oil inlet of the first reversing valve is disconnected from an oil through hole, the oil through hole of the first reversing valve is communicated with an oil return hole, and the first reversing valve discharges pressure oil conveyed by the bidirectional backflow prevention valve back to the oil tank through a first oil drain oil path.
2. The hydraulic control system of an energy efficient grain combine of claim 1, wherein:
the adjustable hydraulic device comprises a constant displacement pump and a pilot logic valve, and an oil outlet of the constant displacement pump is respectively communicated with an oil inlet of the pilot logic valve and an oil inlet of the priority valve; the control oil port of the pilot logic valve is used for receiving feedback pressure of the LS oil path and controlling flow of pressure oil quantitatively pumped back to the oil tank through the feedback pressure;
or (b)
The adjustable hydraulic device is a load-sensitive variable pump, a control oil port of the load-sensitive variable pump is communicated with the LS oil circuit, and the load-sensitive variable pump receives feedback pressure of the LS oil circuit and adjusts pressure and flow of an oil outlet of the load-sensitive variable pump.
3. The hydraulic control system of an energy efficient grain combine of claim 1, wherein:
the LS oil way is provided with a first throttling hole;
a second throttling hole is arranged on the first main oil way;
a third throttling hole is arranged on the first oil drain oil way;
and a control oil way one-way valve is arranged on the first control oil way.
4. The hydraulic control system of an energy efficient grain combine of claim 3, further comprising:
the second valve group comprises a first one-way backflow prevention valve, a second one-way backflow prevention valve, a third one-way backflow prevention valve, a main oil way one-way valve, a first adjustable throttle valve and a pressure reducing valve;
the second one-way backflow prevention valve, the first adjustable throttle valve and the main oil way check valve are sequentially communicated to form a header oil supply oil way, an oil inlet of the second one-way backflow prevention valve is communicated with the main oil way of the executing element through a second main oil way, an oil outlet of the main oil way check valve is respectively communicated with an oil port of a header oil cylinder and an oil port of an energy accumulator, and the LS oil way is communicated with an oil way for connecting the first adjustable throttle valve and the main oil way check valve through a second control oil way;
the oil outlet of the pressure reducing valve is communicated with the main oil drain way through a second oil drain way, and the oil inlet of the third one-way backflow preventing valve is respectively communicated with the oil port of the header oil cylinder and the oil port of the energy accumulator;
an oil inlet of the first one-way backflow prevention valve is communicated with an oil inlet of the second one-way backflow prevention valve, and an oil outlet of the first one-way backflow prevention valve is communicated with the second oil drain way.
5. The hydraulic control system of an energy efficient grain combine of claim 4, wherein:
the second valve group further comprises a normally closed logic valve, an oil inlet of the normally closed logic valve is communicated with an oil outlet of the second one-way backflow prevention valve, and an oil outlet of the normally closed logic valve is communicated with the second oil drain path;
the first comparison oil way of the normally closed logic valve is communicated with an oil inlet of the first adjustable throttle valve, and the second comparison oil way of the normally closed logic valve is communicated with an oil way for connecting the first adjustable throttle valve and the main oil way check valve;
when the oil pressure of the first comparison oil way is larger than the sum of the oil pressure of the second comparison oil way and the spring force of the normally closed logic valve, the normally closed logic valve is in an open state, and the pressure oil in the main oil way of the executive element flows back to the oil tank through the second unidirectional backflow prevention valve, the normally closed logic valve, the second oil drain oil way and the main oil drain oil way in sequence.
6. The hydraulic control system of an energy efficient grain combine of claim 3, further comprising:
the third valve group comprises a second reversing valve and a hydraulic lock which are sequentially communicated, and the second reversing valve is a three-position five-way electromagnetic valve;
the oil inlet of the second reversing valve and the second oil outlet of the priority valve are communicated with a third main oil way sequentially through an execution element main oil way, and a fourth orifice is arranged at the third main oil way;
the control oil port of the second reversing valve is communicated with the LS oil circuit through a third control oil circuit, a one-way valve is arranged at the third control oil circuit, and pressure oil flows to the LS oil circuit through the one-way valve;
the oil return port of the second reversing valve is communicated with the main oil drain way through a third oil drain way;
and the pressure oil drives the double-acting oil cylinder through the second reversing valve and the hydraulic lock in sequence.
7. The hydraulic control system of an energy efficient grain combine of claim 1, wherein:
an oil return filter is arranged on the main oil drain way;
and/or
And two oil filters are arranged on the main pump oil way, and the adjustable hydraulic device is positioned between the two oil filters.
8. The hydraulic control system of an energy efficient grain combine of claim 1, wherein:
the LS oil circuit is connected in parallel with a control safety oil circuit, and a control oil circuit safety valve for detecting the oil pressure of the LS oil circuit is arranged on the control safety oil circuit.
9. The hydraulic control system of an energy efficient grain combine of claim 8, wherein:
and a fifth throttling hole is also arranged on the control safety oil circuit.
10. The hydraulic control system of an energy efficient grain combine of claim 1, wherein:
the main oil drain oil way is communicated with the main pump oil way through a main oil way safety valve for detecting the oil pressure of the main pump oil way.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201810799587.5A CN108547810B (en) | 2018-07-19 | 2018-07-19 | Hydraulic control system of energy-saving grain combine harvester |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201810799587.5A CN108547810B (en) | 2018-07-19 | 2018-07-19 | Hydraulic control system of energy-saving grain combine harvester |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| CN108547810A CN108547810A (en) | 2018-09-18 |
| CN108547810B true CN108547810B (en) | 2024-03-01 |
Family
ID=63492178
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN201810799587.5A Active CN108547810B (en) | 2018-07-19 | 2018-07-19 | Hydraulic control system of energy-saving grain combine harvester |
Country Status (1)
| Country | Link |
|---|---|
| CN (1) | CN108547810B (en) |
Families Citing this family (4)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN111963510A (en) * | 2020-08-31 | 2020-11-20 | 潍柴动力股份有限公司 | Control system and harvester with same |
| CN112377476B (en) * | 2020-12-17 | 2024-03-26 | 徐州徐工环境技术有限公司 | Energy-saving hydraulic system with composite function for sweeper |
| CN113898624A (en) * | 2021-10-09 | 2022-01-07 | 徐工集团工程机械股份有限公司科技分公司 | Fully-variable hydraulic control system, loader and control method |
| CN114704508B (en) * | 2022-04-13 | 2023-01-24 | 浙江大学 | Multi-margin hydraulic system for electro-hydraulic servo six-degree-of-freedom parallel robot |
Citations (6)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN101731058A (en) * | 2008-11-07 | 2010-06-16 | 鞍山海虹农机科技股份有限公司 | Straw chopping and returning self-propelled corn combine harvester |
| CN102511238A (en) * | 2011-12-23 | 2012-06-27 | 浙江大学 | Small-sized full-hydraulic self-propelled windrower |
| CN104132822A (en) * | 2013-05-03 | 2014-11-05 | 兰溪市鸿成汽车零部件有限公司 | Full-hydraulic power steering gear performance test system |
| CN204610402U (en) * | 2015-05-19 | 2015-09-02 | 福田雷沃国际重工股份有限公司 | A kind of combine hydraulic control system |
| BE1021940B1 (en) * | 2013-08-09 | 2016-01-27 | Maschinenfabrik Kemper Gmbh & Co. Kg | MACHINE FOR MAKING CLAIM-BASED HARVEST |
| CN208456938U (en) * | 2018-07-19 | 2019-02-01 | 常州常发农业装备工程技术研究有限公司 | A kind of hydraulic control system of energy-efficient grain combine |
-
2018
- 2018-07-19 CN CN201810799587.5A patent/CN108547810B/en active Active
Patent Citations (6)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN101731058A (en) * | 2008-11-07 | 2010-06-16 | 鞍山海虹农机科技股份有限公司 | Straw chopping and returning self-propelled corn combine harvester |
| CN102511238A (en) * | 2011-12-23 | 2012-06-27 | 浙江大学 | Small-sized full-hydraulic self-propelled windrower |
| CN104132822A (en) * | 2013-05-03 | 2014-11-05 | 兰溪市鸿成汽车零部件有限公司 | Full-hydraulic power steering gear performance test system |
| BE1021940B1 (en) * | 2013-08-09 | 2016-01-27 | Maschinenfabrik Kemper Gmbh & Co. Kg | MACHINE FOR MAKING CLAIM-BASED HARVEST |
| CN204610402U (en) * | 2015-05-19 | 2015-09-02 | 福田雷沃国际重工股份有限公司 | A kind of combine hydraulic control system |
| CN208456938U (en) * | 2018-07-19 | 2019-02-01 | 常州常发农业装备工程技术研究有限公司 | A kind of hydraulic control system of energy-efficient grain combine |
Also Published As
| Publication number | Publication date |
|---|---|
| CN108547810A (en) | 2018-09-18 |
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| CN108547810B (en) | Hydraulic control system of energy-saving grain combine harvester | |
| CN103807231B (en) | Hydraulic drive apparatus for work machine | |
| CN103807232B (en) | The fluid pressure drive device of engineering machinery | |
| CN103047208B (en) | Load-sensitive electro-hydraulic proportional multi-way valve | |
| US7219591B2 (en) | Hydraulic control arrangement | |
| CN113464514B (en) | Integrated electric control multi-way valve and crane | |
| CN202851491U (en) | Load-sensitive multi-way valve used in loader variable system | |
| CN203297181U (en) | System adopting load sensitivity control | |
| CN113482090B (en) | Main control valve, constant-variable hydraulic system and loader | |
| CN104029721A (en) | Hydraulic steering device for loader | |
| CN102562694B (en) | Load-sensing regulating type hydrostatic drive system | |
| CN113431127A (en) | Main control valve, fixed variable hydraulic system and loader | |
| CN208456938U (en) | A kind of hydraulic control system of energy-efficient grain combine | |
| CN107725504B (en) | Hydraulic system capable of providing proper performance for load and hydraulic control method | |
| CN113494111B (en) | Main control valve, fixed variable hydraulic system and loader | |
| CN214837438U (en) | Spiral machine closed type hydraulic system for shield machine and shield machine | |
| CN210290307U (en) | Digital control non-interference signal and anti-saturation flow load sensitive integrated valve | |
| CN100487253C (en) | Functional switching set of servo actuator | |
| CN212717444U (en) | Hydraulic control system and work vehicle | |
| CN112610547A (en) | Spiral machine closed type hydraulic system for shield machine and shield machine | |
| CN113915185A (en) | Load port independent control load sensitive multi-way valve and hydraulic system | |
| CN108483264B (en) | The hydraulic control system and hoisting machinery of hoisting machinery | |
| CN209704952U (en) | A kind of the load-sensitive adjustable hydraulic system and drilling machine of drilling machine | |
| CN111720376A (en) | Flow dividing valve, hydraulic system thereof and engineering machinery | |
| CN108516467B (en) | The hydraulic control system and hoisting machinery of hoisting machinery |
Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| PB01 | Publication | ||
| PB01 | Publication | ||
| SE01 | Entry into force of request for substantive examination | ||
| SE01 | Entry into force of request for substantive examination | ||
| CB02 | Change of applicant information | ||
| CB02 | Change of applicant information |
Address after: 539 Xiacheng South Road, Wujin national high tech Industrial Development Zone, Changzhou City, Jiangsu Province Applicant after: CHANGZHOU CHANGFA AGRICULTURE EQUIPMENT ENGINEERING TECHNOLOGY RESEARCH Co.,Ltd. Address before: 213175 Changfa Industrial Park, Lijia Town, Wujin District, Changzhou City, Jiangsu Province Applicant before: CHANGZHOU CHANGFA AGRICULTURE EQUIPMENT ENGINEERING TECHNOLOGY RESEARCH Co.,Ltd. |
|
| GR01 | Patent grant | ||
| GR01 | Patent grant |