CN110714910B - Valve plate capable of distributing different flow differences - Google Patents

Valve plate capable of distributing different flow differences Download PDF

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Publication number
CN110714910B
CN110714910B CN201911137862.8A CN201911137862A CN110714910B CN 110714910 B CN110714910 B CN 110714910B CN 201911137862 A CN201911137862 A CN 201911137862A CN 110714910 B CN110714910 B CN 110714910B
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oil
window
windows
layer
oil discharge
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CN110714910A (en
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张晓刚
权龙�
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Taiyuan University of Technology
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Taiyuan University of Technology
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    • FMECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F04POSITIVE - DISPLACEMENT MACHINES FOR LIQUIDS; PUMPS FOR LIQUIDS OR ELASTIC FLUIDS
    • F04BPOSITIVE-DISPLACEMENT MACHINES FOR LIQUIDS; PUMPS
    • F04B53/00Component parts, details or accessories not provided for in, or of interest apart from, groups F04B1/00 - F04B23/00 or F04B39/00 - F04B47/00

Abstract

The invention discloses a valve plate capable of distributing different flow differences for a multi-oil-outlet high-pressure axial plunger pump. The port plate consists of three layers: the middle layer flow distribution window protruding part is matched with the positioning parts of the upper layer and the bottom layer in a high-pressure sealing mode. The valve plate is in a multi-valve window series structure form: there are multiple oil suction windows and two (or more) oil discharge windows, one side is the distribution window C, the other side is two (or more) distribution windows A, B arranged in series, the multiple distribution windows are located on the same pitch circle. The flow distribution plate middle layer can rotate freely through servo control driving, the area size of A, B flow distribution windows is changed, the flow rate of A, B flow distribution windows can be changed through adjustment of the flow distribution plate middle layer, so that the two flow distribution windows output different flow rates, the two cavities of the differential oil cylinder with different flow rate differences correspond to each other, the differential oil cylinder with different flow rate differences can be directly controlled to act by one pump, and the practical value is high.

Description

Valve plate capable of distributing different flow differences
Technical Field
The invention belongs to the technical field of hydraulic pressure, and particularly relates to a valve plate capable of distributing different flow differences.
Background
At present, the direct pump control technology has made a great progress, a high dynamic response servo and a proportional axial plunger variable pump are successfully researched and developed, a variable rotating speed control technology is introduced, the technologies are used on a pump control symmetrical oil cylinder to obtain a good effect, but the effect is not ideal when the technologies are applied to a differential oil cylinder; the reason is that these pumps can only deliver symmetrical flow, and if they are directly connected to the differential cylinder, many auxiliary methods are needed. When a single axial plunger variable pump is adopted to directly control the movement of the differential oil cylinder, because the two cavities of the differential oil cylinder have volume difference, the flow of the rodless cavity of the connecting oil cylinder is more than the part of the rod cavity, the redundant flow must be solved when the hydraulic oil of the differential oil cylinder flows into the symmetrical flow pump.
The invention patent 'closed electro-hydraulic control system' (patent number 200610012476.2) discloses a three-oil-port axial plunger pump, wherein a valve plate is provided with three suction and discharge oil flow distribution windows which are arranged in series or in parallel, and the flow passing through a first suction and discharge oil flow distribution window is equal to the sum of the flow passing through a second suction and discharge oil flow distribution window and the flow passing through a third suction and discharge oil flow distribution window. The invention patent 'multi-oil-port axial plunger hydraulic pump' (patent number 2010101975689) discloses a structure scheme of a valve plate, wherein the valve plate is provided with three oil discharge kidney-shaped grooves and an oil absorption kidney-shaped groove, the first oil discharge kidney-shaped groove and the third oil discharge kidney-shaped groove are connected in series, the second oil discharge kidney-shaped groove, the first oil discharge kidney-shaped groove and the third oil discharge kidney-shaped groove are arranged on one side of the valve plate in parallel, and the oil absorption kidney-shaped groove is arranged on the other side of the valve plate.
The flow distribution plate structures are specially designed for the axial plunger pump with the asymmetric flow distribution structure, but the flow distribution plate structures only prove that the axial plunger pump with the asymmetric flow distribution structure can directly control the action of a differential cylinder, is only suitable for controlling the action of the differential cylinder with a certain cavity difference, and cannot be realized for most of differential oil cylinders with different cavity differences. The valve plate capable of automatically distributing different flow differences must be redesigned and manufactured, and the valve plate is applied to differential oil cylinders with different cavity differences.
Disclosure of Invention
In view of the above requirements, the present invention aims to design a port plate capable of distributing different flow rate differences, which can solve the problem of asymmetric flow rates of two cavities of a differential oil cylinder with different cavity differences, and corresponds to the two cavities of the differential oil cylinder with different cavity differences by adjusting the flow distribution ratio of two flow distribution windows. The valve plate is used for the axial plunger pump with the asymmetric valve structure, can realize that the asymmetric flow of two cavities of the differential oil cylinder with different cavity differences can be solved by using one pump, and the action of the differential oil cylinder with different cavity differences is controlled.
The invention is realized by adopting the following technical scheme: a can distribute the valve plate of different flow differences, the said valve plate is a round plate, there are multiple oil suction windows C and at least two oil drainage windows on the round plate; the adjacent oil absorption windows C are connected by a framework; the oil suction window C and the oil discharge window are arc waist-shaped holes, and the flow distribution windows are positioned on the same reference circle; the oil absorption window C and the oil discharge window have the same width; the valve plate is divided into three layers: the flow distribution plate is formed by three layers of high-precision fit, a seal bearing high pressure is formed, and the middle layer can rotate around the center of the flow distribution plate; each layer of valve plate is provided with an independent valve window structure.
The flow distribution plate intermediate layer can rotate freely, the area size of at least two flow distribution windows is changed, and the flow rate of the at least two flow distribution windows can be changed through the adjustment of the flow distribution plate intermediate layer, so that the at least two flow distribution windows output different flow rates. The valve plate can solve the technical difficulty of directly controlling the hydraulic cylinder by the pump, namely the technology of directly controlling the symmetrical cylinder by the pump is mature, but the pump can not directly control the differential cylinder and needs the assistance of a valve control loop; in production practice, the output force of the symmetrical cylinder is small, the output force of the differential cylinder is large, and the demand of the market on the differential cylinder is very large; with the continuous development of green energy-saving hydraulic pressure, the problems of heating, leakage and the like of a valve control loop exist, and the technology of directly pumping and controlling a differential cylinder becomes a trend. The thrust plate of the invention is characterized in that the area of the flow through the thrust window is adjusted to correspond to two cavities of the differential oil cylinder with different flow differences, so that the differential oil cylinder with different flow differences can be directly controlled to act by one pump without the assistance of a valve control loop, and the thrust plate has great practical value.
Drawings
Fig. 1 is a schematic structural view of the port plate of the present invention.
Fig. 2 is a schematic view of the plane structure (front side direction) of the port plate of the present invention.
Fig. 3 is a schematic plan view (rear direction) of the port plate of the present invention.
Fig. 4 is a perspective view (front side direction) of the port plate of the present invention.
Fig. 5 is a perspective view (rear direction) of the port plate of the present invention.
Fig. 6 is a perspective (exploded) view of the port plate of the present invention.
Fig. 7 is a schematic view of the upper layer plane structure (front side direction) of the port plate of the present invention.
Fig. 8 is a schematic view of the upper layer plane structure (rear side direction) of the port plate of the present invention.
Fig. 9 is a perspective view (front side direction) of the upper surface layer of the port plate of the present invention.
Fig. 10 is a perspective view (rear direction) of the upper surface layer of the port plate of the present invention.
Fig. 11 is a schematic view of the plane structure (front side direction) of the intermediate layer of the port plate of the present invention.
Fig. 12 is a schematic view of the plane structure (rear direction) of the intermediate layer of the port plate of the present invention.
Fig. 13 is a perspective view (front side direction) of the intermediate layer of the port plate of the present invention.
Fig. 14 is a perspective view (rear direction) of the intermediate layer of the port plate of the present invention.
Fig. 15 is a plan view (front side direction) of the bottom surface layer of the port plate of the present invention.
Fig. 16 is a plan view (rear direction) of the bottom surface layer of the port plate of the present invention.
Fig. 17 is a perspective view of the bottom layer of the port plate of the present invention.
The main elements in the figures are symbolically illustrated:
1-port plate 2-oil suction window 3-A oil discharge window 4-B oil discharge window 5-upper layer 6-middle layer 7-bottom layer 8-oil suction window trapped oil groove 9-oil discharge window trapped oil groove 10-middle layer regulating part trapped oil groove 11-transition area friction pair regulating part 12-rotary servo control regulating mechanism, 13-trapped oil groove, 14-positioning boss and 15-positioning hole.
Detailed Description
The technical scheme of the invention is further explained by combining the attached drawings. It should be noted that the description of specific embodiments in this section should not be taken as limiting the scope of the invention in any way. Furthermore, the embodiments and features of the embodiments in this section may provide further corroboration to the claims without conflict.
The invention relates to a valve plate capable of distributing different flow differences, which specifically comprises the following components: there are a plurality of oil absorption windows C2 and two oil extraction windows on the port plate, wherein two oil extraction windows include: an oil discharge window A3 and an oil discharge window B4. The oil suction window C, A and the oil discharge window B are circular arc waist-shaped holes, and the three flow distribution windows are positioned on the same reference circle. The oil absorption window C has the same width as the oil discharge window A and the oil discharge window B. The valve plate is divided into three layers: the flow distribution plate comprises an upper surface layer 5, a middle layer 6 and a bottom surface layer 7, wherein the flow distribution plate 1 is formed by three layers of sealing combination, and the middle layer 6 can freely rotate around the center of the flow distribution plate 1 through servo control. Each layer of valve plate is provided with an independent valve window structure. The valve plate is in a multi-valve window series structure form: there are several oil sucking windows and two oil exhausting windows, one side is flow distributing window C and the other side is two (several) serially arranged flow distributing windows A, B, which are located in the same graduated circle. The port structures on the upper surface layer 5, the middle layer 6 and the bottom surface layer 7 together form an A oil discharge window 3, a B oil discharge window 4 and an oil suction window C2 on the port plate.
As shown in fig. 7 to 10, a plurality of oil absorption windows and an oil discharge window are formed on the upper surface layer 5 around the center thereof; the adjacent oil absorption windows are connected by a framework; when the oil suction window rotates clockwise, the oil suction window is correspondingly provided with an oil suction window trapped oil groove 8, and the oil discharge window is correspondingly provided with an oil discharge window trapped oil groove 9; the lower surface middle convex part (positioning boss 14) is used for positioning the middle layer 6 and forming corresponding sealing; the upper surface layer 5 is provided with 3 positioning holes 15 (as positioning holes on a port plate) on the outer side of the oil discharge window, and the positioning holes are used as corresponding holes for the rotation direction of the pump.
As shown in fig. 15 to 17, a plurality of oil suction windows and an oil discharge window are formed on the bottom layer 7 around the center thereof; the adjacent oil absorption windows are connected by a framework; when the oil suction window and the oil discharge window rotate clockwise, the oil suction window and the oil discharge window correspond to the oil trap-free oil groove; the upper surface middle convex part (positioning boss 14) is used for positioning the middle layer 6 and forming corresponding sealing; the structural parameters of the oil absorption window and the oil discharge window are consistent with the structural parameters of the upper surface layer 5; the bottom layer 7 is provided with 3 positioning holes at the outer side of the oil discharge window, and 3 positioning holes 15 (corresponding to the positioning holes on the upper layer) are arranged at the outer side of the oil discharge window and used as corresponding holes for the rotation direction of the pump.
As shown in fig. 10 to 14, a plurality of oil absorption windows and two oil discharge windows are arranged on the middle layer 6 around the center thereof, the spread angle of the oil absorption windows is larger than that of the oil absorption windows of the upper layer 5 and the bottom layer 7, the oil trapping area is changed into a through-flow area, and the through-flow area of the oil absorption windows is not affected; the spread angles of the two oil discharge windows of the middle layer 6 are the same; the middle parts of two oil discharge windows on the front and rear surfaces of the middle layer are both provided with convex transition region friction pair adjusting parts 11, and the transition region friction pair adjusting parts 11 on the front and rear surfaces are respectively embedded in the oil discharge windows of the upper layer 5 and the bottom layer 7; on the raised transition area friction pair adjustment part 11, the corresponding middle layer adjustment part is trapped in the oil groove 10 when the pump rotates in the clockwise direction.
A rotary servo control adjustment mechanism 12 is provided on the outer side of the intermediate layer 6, and the intermediate layer 6 can be freely rotated around the center thereof.
According to the structural schematic diagram of the port plate shown in fig. 1, fig. 2 and fig. 3, the right side of the port plate is provided with a plurality of oil suction windows C2, the left side is provided with two oil discharge windows, an a oil discharge window 3 and a B oil discharge window 4, and the flow distribution area of the a oil discharge window 3 and the B oil discharge window 4 is variable. The valve plate is divided into three layers: the flow distribution plate comprises an upper surface layer 5, a middle layer 6 and a bottom surface layer 7, and the flow distribution plate 1 is formed by sealing and combining three layers. An oil absorption window C of the port plate is correspondingly provided with an oil absorption window oil trapping groove 8 when the pump rotates clockwise, and an oil discharge window oil trapping groove 9 when the pump rotates clockwise. According to the schematic structural diagrams of the intermediate layer of the port plate shown in fig. 6 and 7, the spread angles of two oil discharge windows of the intermediate layer 6 are the same, a protruded transition area friction pair adjusting part 11 is arranged between the two oil discharge windows, and the protruded transition area friction pair adjusting part 11 is correspondingly provided with an intermediate layer adjusting part trapped in an oil groove 10 when the pump rotates clockwise; the friction pair adjusting parts 11 in the transition areas of the front and the back are respectively embedded in the oil drainage windows of the upper surface layer 5 and the bottom surface layer 7; the intermediate layer 6 is provided on the outer side with a rotary servo control adjusting mechanism 12 for rotating the intermediate layer 6 about the center. The transition region friction pair adjusting part 11 of the middle layer 6 can adjust the flow distribution regions of the oil discharge window A3 and the oil discharge window B4 to enable the oil discharge windows to pass different flow rates.
In the figure, the A, B, C three flow distribution windows only correspond to one rotation direction of the pump, and in specific use, if one of the windows is an oil discharge window, the other two windows are oil suction windows; if two are oil drainage windows, the other is an oil absorption window. Theoretically, when the oil outlet window is one Q1, the flow rate is equal to the sum of the flow rates when the oil outlet windows are two Q2 and Q3, namely Q1= Q2+ Q3; the flow difference between Q1 and Q2 or Q3 can be matched with the volume difference of two cavities of the differential oil cylinder. When the oil outlet windows are two, one window is required to enter a rod cavity of the differential cylinder, the other window is mainly used for hydraulic oil cooling heat exchange and oil supplement, and flow values of Q2 and Q3 can be increased and decreased mutually on the premise that the total amount is not changed. For example: the window C is connected with a rodless cavity of the differential oil cylinder, the window A is connected with a rod cavity of the differential oil cylinder, and the window B is connected to the low-pressure oil tank; when the windows A and B absorb oil and the window C discharges oil, the piston rod of the differential oil cylinder extends out; when the window C absorbs oil and the windows A and B discharge oil, the pressure oil of the window A drives the piston rod of the differential oil cylinder to retract, and the window B discharges redundant oil back to the low-pressure oil tank.
When the valve plate is used for the asymmetric valve pump to directly drive the differential oil cylinder to move, the valve window A, B, C can output flow, the flow of the window C is equal to the sum of the flows of the windows A, B, and the volume ratio of the rodless cylinder and the rod cavity of the differential oil cylinder is consistent with the flow ratio between the window C and the window A or B; the flow distribution adjustment of the windows A and B can be realized by rotating the middle layer through servo control, the flow distribution of the oil ports A and B can be increased and decreased mutually on the premise that the total amount is equal to the flow of the port C, and the volume ratio of rodless cylinders to rod cavities of different differential cylinders is completely met. Thus, the motion control of the differential oil cylinders with different cavity ratios can be realized by using one pump without an auxiliary valve loop oil supplementing device.
Although the present invention has been described with reference to the accompanying drawings, the present invention is not limited to the above-described embodiments, which are merely illustrative and not restrictive, and those skilled in the art can make various modifications without departing from the spirit and scope of the present invention as defined in the appended claims.

Claims (5)

1. A port plate capable of dispensing different flow differentials, said port plate being a circular plate characterized by: the circular plate is provided with a plurality of oil absorption windows C (2) and at least two oil discharge windows; the adjacent oil absorption windows C (2) are connected by a framework; the oil suction window C (2) and the oil discharge window are arc waist-shaped holes and are positioned on the same reference circle; the oil absorption window C (2) and the oil discharge window have the same width; the valve plate is divided into three layers: the flow distribution plate comprises an upper surface layer (5), a middle layer (6) and a bottom surface layer (7), wherein the flow distribution plate (1) is formed by three layers of high-precision fit to form a seal to bear high pressure, and the middle layer (6) can rotate around the center of the flow distribution plate (1); each layer of flow distribution plate is provided with an independent flow distribution window structure, raised transition region friction pair adjusting parts (11) are arranged between two oil discharge windows on the front surface and the rear surface of the middle layer (6), and the transition region friction pair adjusting parts (11) on the front surface and the rear surface are respectively embedded in the oil discharge windows of the upper layer (5) and the bottom layer (7).
2. A port plate capable of dispensing different flow differentials as claimed in claim 1, wherein: a plurality of oil absorption windows and an oil discharge window are arranged on the upper surface layer (5) around the center of the upper surface layer; the adjacent oil absorption windows are connected by a framework; when the oil suction window rotates clockwise, the oil suction window is correspondingly provided with an oil suction window oil trapping groove (8), and the oil discharge window is correspondingly provided with an oil discharge window oil trapping groove (9); the middle convex part of the lower surface is used for positioning the middle layer (6) and forming a corresponding seal; the upper surface layer (5) is provided with 3 positioning holes (15) which are positioned outside the oil discharge window and are used as corresponding holes for the rotation direction of the pump.
3. A port plate capable of dispensing different flow differentials as claimed in claim 1, wherein: a plurality of oil absorption windows and an oil discharge window are arranged on the bottom surface layer (7) around the center of the bottom surface layer; the adjacent oil absorption windows are connected by a framework; when the oil suction window and the oil discharge window rotate clockwise, the oil suction window and the oil discharge window correspond to the oil trap-free oil groove; the middle convex part of the upper surface is used for positioning the middle layer (6) and forming a corresponding seal; the structural parameters of the oil absorption window and the oil discharge window are consistent with the structural parameters of the upper layer (5); the bottom layer (7) is provided with 3 positioning holes (15) outside the oil discharge window as corresponding holes for the rotation direction of the pump.
4. A port plate capable of dispensing different flow differentials as claimed in claim 1, wherein: a plurality of oil absorption windows and two oil discharge windows are arranged on the middle layer (6) around the center of the middle layer, the spread angle of the oil absorption windows is larger than that of the oil absorption windows of the upper layer (5) and the bottom layer (7), the oil trapping area is changed into a through-flow area, and the through-flow area of the oil absorption windows is not affected; the spread angles of the two oil discharge windows of the middle layer (6) are the same; on the convex transition area friction pair regulating part (11), an intermediate layer regulating part trapped in the oil groove (10) is correspondingly arranged when the pump rotates along the clockwise direction.
5. A port plate capable of dispensing different flow differentials as claimed in claim 1, wherein: a servo control rotation adjusting mechanism (12) is arranged on the outer side of the middle layer (6) and can enable the middle layer (6) to rotate freely around the center of the middle layer.
CN201911137862.8A 2019-11-20 2019-11-20 Valve plate capable of distributing different flow differences Active CN110714910B (en)

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CN110714910B true CN110714910B (en) 2021-08-03

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Citations (5)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JP2014098327A (en) * 2012-11-14 2014-05-29 Toshiba Mach Co Ltd Valve plate, and piston pump motor using valve plate
CN203627224U (en) * 2013-06-26 2014-06-04 包双龙 Bi-functional variable vane pump
CN104373630A (en) * 2013-08-17 2015-02-25 宋久林 Rotary proportional reversing valve
CN106593852A (en) * 2017-01-20 2017-04-26 太原理工大学 Port plate structure of three-oil hole axial plunger pump
CN107044456A (en) * 2017-04-07 2017-08-15 江苏师范大学 A kind of flow waist-shaped hole it is variable enter it is fuel-displaced wait flow four-way hydraulic transformer

Patent Citations (5)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JP2014098327A (en) * 2012-11-14 2014-05-29 Toshiba Mach Co Ltd Valve plate, and piston pump motor using valve plate
CN203627224U (en) * 2013-06-26 2014-06-04 包双龙 Bi-functional variable vane pump
CN104373630A (en) * 2013-08-17 2015-02-25 宋久林 Rotary proportional reversing valve
CN106593852A (en) * 2017-01-20 2017-04-26 太原理工大学 Port plate structure of three-oil hole axial plunger pump
CN107044456A (en) * 2017-04-07 2017-08-15 江苏师范大学 A kind of flow waist-shaped hole it is variable enter it is fuel-displaced wait flow four-way hydraulic transformer

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