CN116771955A - Decimal coded electrohydraulic digital flow valve - Google Patents
Decimal coded electrohydraulic digital flow valve Download PDFInfo
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- CN116771955A CN116771955A CN202310740407.7A CN202310740407A CN116771955A CN 116771955 A CN116771955 A CN 116771955A CN 202310740407 A CN202310740407 A CN 202310740407A CN 116771955 A CN116771955 A CN 116771955A
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- 239000012530 fluid Substances 0.000 claims description 8
- 238000004891 communication Methods 0.000 abstract description 3
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- 230000007547 defect Effects 0.000 description 3
- 230000005540 biological transmission Effects 0.000 description 2
- 230000001276 controlling effect Effects 0.000 description 2
- 230000009286 beneficial effect Effects 0.000 description 1
- 238000006243 chemical reaction Methods 0.000 description 1
- 238000003754 machining Methods 0.000 description 1
- 238000012986 modification Methods 0.000 description 1
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Abstract
The valve includes step motor, valve body, valve sleeve, switch valve group and valve core. The valve sleeve is provided with nine low-level oil ports and n high-level oil ports, and the area ratio of the low-level oil ports is 1:2:3:4:5:6:7:8:9, a step of performing the process; the area of the high-order oil port is 10 times of the minimum low-order oil port area, namely 10:20:40:80:160: …: 10X 2 n . Under the drive of the stepping motor, the inner cavity of the valve core can be communicated with any one low-level oil port, and the communication state between the high-level oil port and the inner cavity of the valve core is realized by the codes of on-off of n switch valves. The flow value of the whole valve is (10 multiplied by 2) by controlling the on-off of the low-level oil port and the high-level oil port n+1 +1) pieces. The valve has the advantages of multiple control points, high precision, strong pollution resistance, high reliability, low requirement on the precision of the driving motor and the like.
Description
Technical Field
The invention belongs to the field of digital hydraulic pressure, and particularly relates to a decimal coded electrohydraulic digital flow valve.
Background
The electrohydraulic digital control valve is a valve directly controlled by a digital signal and is discrete control, so that the program control of hydraulic characteristic parameters (pressure, flow and direction) can be flexibly realized without D/A conversion. Compared with an electrohydraulic servo valve and an electrohydraulic proportional valve, the valve has the advantages of high repetition precision, good linearity, small hysteresis, stable and reliable work, low price, strong anti-interference and anti-pollution capabilities and the like. In a computer real-time control electrohydraulic control system, an electrohydraulic digital valve partially replaces an electrohydraulic proportional valve or an electrohydraulic servo valve to work, and is a brand new valve type which is mutually competing and promoting with the electrohydraulic proportional valve and the electrohydraulic servo valve in the future.
At present, electrohydraulic digital valves can be divided into three types according to different control modes: binary coded digital valves, incremental digital valves, and high-speed switching digital valves. The binary coded digital valve consists of a plurality of switch valves with only two states of on-off, the flow coefficient of each valve is designed according to a binary sequence, the more the number of the switch valves is, the smaller the minimum control flow is, the higher the resolution precision is, for example, the digital valve formed by 8 switch valves can obtain 2 8 And a flow value. The valve has the advantages of good linearity, high repetition precision and strong pollution resistance, and the defects of high-precision binary coded digital valve, more number of needed switch valves, complex structure and high price. The incremental digital valve uses a stepping motor or a servo motor to drive a valve core to move, controls the opening size of the valve to make the output flow of the valve proportional to the rotation angle of the motor, and has the defect that the control flow precision is limited by the resolution precision and the control precision of the motor, so if the stepping motor is used for driving, the control precision is poor, and the high-performance servo motor driving can improve the precision of the valve, but the cost is high. The high-speed switch digital valve is to switch the valve at high speed by a pulse width control (PWM) mode, so as to achieve the purpose of controlling the flow, and the larger the product of the valve opening time and the switching frequency is, the larger the control flow is, and the greatest disadvantage of the valve is that the flow impact and pulsation caused by the high-speed movement of the valve are not solved well at present.
Based on the background, the applicant provides a decimal coded electrohydraulic digital flow valve, and the novel electrohydraulic digital flow valve has the advantages of a binary coded electrohydraulic digital valve and an incremental electrohydraulic digital valve, and has the advantages of good linearity, high repetition precision, strong pollution resistance, simple structure, reliable work, low price and the like.
Disclosure of Invention
In order to overcome the defects, the invention provides a decimal-coded electrohydraulic digital flow valve, which aims to solve the problems that the existing binary-coded electrohydraulic digital valve needs more switching valves in high-precision control and the incremental electrohydraulic digital flow valve needs high-precision high-resolution servo motor driving in high-precision control.
In order to achieve the above purpose, the technical scheme adopted by the invention is as follows:
the utility model provides a decimal code electrohydraulic digital flow valve, includes step motor, valve body, valve pocket, switch valves and case, step motor fixes on the valve body, step motor's output shaft with the case upper end is connected, the case is in the valve pocket, step motor drive case at the valve pocket free rotation, the lower extreme and the valve body clearance fit of case, valve pocket and valve body interference fit are provided with low level hydraulic fluid port and a plurality of including macropore, aperture's shoulder hole on the valve pocket, and wherein the aperture is high level hydraulic fluid port, and the switch valve is installed on the valve body for control high level hydraulic fluid port and the intercommunication state of case inner chamber, and low level hydraulic fluid port and case inner chamber and intercommunication state are realized through the rotation of case.
Further preferably, the number of the low-level oil ports is nine, the shape of the low-level oil ports is round holes or square holes, the number of the high-level oil ports is not less than 1, and the shape of the high-level oil ports is round holes or square holes.
Further preferably, the upper end of the valve core is provided with a transmission hole connected with the output shaft of the stepping motor, the inner part of the valve core is provided with a valve core inner cavity, the lower end of the valve core is communicated with the oil outlet channel, the outer surface of the valve core is provided with a second annular groove and a low-position flow distribution hole, the second annular groove is internally provided with a high-position flow distribution hole communicated with the valve core inner cavity, the low-position flow distribution hole is directly communicated with the valve core inner cavity, the outer surface of the lower part of the valve core is in clearance fit with the valve body, the valve core is supported, the free rotation of the valve core is not influenced, and the outlet of the valve core inner cavity is communicated with the oil outlet channel on the valve body.
Further preferably, the valve sleeve is of an annular structure, the outer surface of the valve sleeve is provided with a first annular groove, nine low-level oil ports are uniformly distributed in the first annular groove along the circumferential direction, the flow area ratio of the nine low-level oil ports is 1:2:3:4:5:6:7:8:9, the valve sleeve is consistent with the height of the low-level distributing holes, the nine low-level oil ports are respectively communicated with the low-level distributing holes in the rotating process of the valve core, and the high-level oil ports are communicated with a second annular groove on the outer surface of the valve core.
Further preferably, a low-level oil inlet hole communicated with the first annular groove is arranged in an oil inlet channel of the valve body, four communicated oil channels are arranged in the valve body to form a square high-pressure oil cavity and are communicated with the oil inlet channel of the valve body, an outlet of an inner cavity of the valve core is communicated with and coaxial with an oil outlet channel, the switch valve group consists of a plurality of switch valves arranged on the valve body, an oil inlet end of the switch valve group is communicated with the square high-pressure oil cavity, and an oil outlet end of the switch valve group is communicated with a high-level oil port on the valve sleeve.
Further preferably, the width of the second annular groove is larger than the maximum diameter of the high-level oil port on the valve sleeve, the sum of the flow areas of the high-level distributing holes in the second annular groove is larger than the sum of the flow areas of the high-level oil port, and the diameter of the low-level distributing holes is larger than the maximum diameter of the low-level oil port.
Further preferably, the number of the high-order flow distribution holes is at least 1.
Further optimizing, the flow area ratio of the high-order oil port is 10 times of the binary sequence of the minimum low-order oil port area, namely, 10:20:40:80:160: …: 10X 2 n Wherein n represents the number of on-off valves.
Further preferably, the number of the switch valves is the same as that of the high-level oil ports, and the switch valves can be electromagnetic switch valves or piezoelectric switch valves. .
The beneficial effects of the invention are as follows:
1. the flow area of the electrohydraulic digital flow valve is divided into a high position and a low position, the low position is controlled by a stepping motor, the high position is controlled by a switch valve group, and more flow values can be controlled by fewer control elements. The number of controllable flow values of the binary-coded electrohydraulic digital flow valve with n switching valves is 2 n And the number of the control flow values of the invention is 10 multiplied by 2 n+1 +1, the control accuracy is higher;
2. the diameter of the low-position distributing hole on the valve core is larger than the maximum diameter of the low-position oil port, so that the precision of the valve is not influenced when the low-position distributing hole and the low-position oil port are not concentric. The sum of the flow areas of the high-order flow distribution holes is larger than the sum of the flow areas of the high-order oil ports, so that the flow passing through the high-order flow distribution holes is ensured to be completely determined by the flow areas of the high-order oil ports, and the flow passing through the high-order flow distribution holes is in a controllable state;
3. the number of the low-level oil ports controlled by the stepping motor is nine, namely, the stepping motor only needs to rotate nine positions, so that the requirement on the resolution precision of the stepping motor is greatly reduced. In addition, the diameter of the low-level oil port is smaller, the hydraulic power is lower, and the stepping motor can directly drive the valve core without a speed reducing device. The high-level oil port is positioned in the stepped hole, so that the depth of the high-level oil port is reduced, the machining of an elongated hole is avoided, and in addition, the outflow of the hole with smaller thickness is more stable according to the outflow principle of the hole opening;
in summary, the invention has the characteristics of binary coded electrohydraulic digital flow valve and incremental electrohydraulic digital flow valve, needs less switching valve quantity during high-precision control, does not need high-precision servo motor driving, and has the advantages of more control points, high precision, good linearity, strong pollution resistance, reliable work, low price and the like.
Drawings
FIG. 1 is a block diagram of a decimal-encoded electro-hydraulic digital valve;
FIG. 2 is a diagram of the oil passages of a decimal-encoded electrohydraulic digital valve;
FIG. 3 is a schematic diagram of a low-order flow area of a decimal-encoded electro-hydraulic digital valve;
FIG. 4 is a schematic diagram of the high-order flow area of a decimal-encoded electro-hydraulic digital valve;
the marks in the figure: 1. the valve comprises a stepping motor, 2, a valve body, 3, a valve sleeve, 4, a switching valve, 5, a valve core, 6, a valve core inner cavity, 7, an oil outlet channel, 8, a low-level distributing hole, 9, a low-level oil port, 10, a first annular groove, 11, a low-level oil inlet hole, 12, an oil inlet channel, 13, a high-level oil port, 14, a second annular groove, 15, a high-level distributing hole, 16 and a square high-pressure oil cavity.
Detailed Description
The technical solutions in the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings.
As shown in fig. 1, the decimal coded electrohydraulic digital flow valve comprises a stepping motor 1, a valve body 2, a valve sleeve 3, a switch valve group and a valve core 5, wherein the stepping motor 1 is fixed on the valve body 2, an output shaft of the stepping motor 1 is connected with the upper end of the valve core 5, the valve core 5 is positioned in the valve sleeve 3, the stepping motor 1 drives the valve core 5 to freely rotate in the valve sleeve 3, the lower end of the valve core 5 is in clearance fit with the valve body 2, and the valve sleeve 3 is in interference fit with the valve body 2. As shown in fig. 3 and 4, the valve sleeve 3 of this example is provided with nine low-level oil ports 9 and four high-level oil ports 13, and the switch valve group is mounted on the valve body 2 and is used for controlling the communication state between the high-level oil ports 13 and the valve core inner cavity 6, and the communication state between the low-level oil ports 9 and the valve core inner cavity 6 is realized through the rotation of the valve core 5.
The upper end of the valve core 5 is provided with a transmission hole connected with the output shaft of the stepping motor 1, a valve core inner cavity 6 is arranged in the valve core, the lower end of the valve core inner cavity is communicated with the oil outlet channel 7, the outer surface of the valve core inner cavity is provided with a second annular groove 14 and low-position distributing holes 8, the second annular groove 14 is internally provided with at least 1 high-position distributing hole 15 communicated with the valve core inner cavity 6, the low-position distributing holes 8 are directly communicated with the valve core inner cavity 6, the outer surface of the lower part of the valve core 5 is in clearance fit with the valve body 2, the free rotation of the valve core 5 is not influenced while the valve core inner cavity 5 is supported, and the outlet of the valve core inner cavity 6 is communicated with the oil outlet channel 7 on the valve body 2.
As shown in fig. 3 and 4, the valve sleeve 3 is of an annular structure, the outer surface of the valve sleeve is provided with a first annular groove 10, nine low-level oil ports 9 are uniformly distributed in the first annular groove 10 along the circumferential direction, the flow area ratio of the nine low-level oil ports 9 is 1:2:3:4:5:6:7:8:9, the flow area ratio is consistent with the height of the low-level distributing holes 8, and the flow area of the high-level oil ports 13 is 10 times of a binary sequence of the minimum area in the low-level oil ports 9, namely, the flow area ratio is 10:20:40:80.
as shown in fig. 1-4, nine low-level oil ports are respectively communicated with the low-level distributing hole 8 in the rotating process of the valve core 5, four stepped holes are formed in the outer surface of the valve sleeve 3, and small holes are formed in the valve sleeve, and the high-level oil ports are communicated with the second annular groove 14. The width of the second annular groove 14 is larger than the maximum diameter of the high-level oil port 13 on the valve sleeve 3, the sum of the flow areas of the high-level distributing holes 15 in the second annular groove 14 is larger than the sum of the flow areas of the high-level oil port 13, and the diameter of the low-level distributing hole 8 is larger than the maximum diameter of the low-level oil port 9.
The valve body 2 is internally provided with a low-position oil inlet hole 11 communicated with the first annular groove 10, the interior of the valve body 2 is provided with four communicated oil channels to form a square high-pressure oil cavity 16 and communicated with the oil inlet channel 7 of the valve body, the outlet of the valve core inner cavity 6 is communicated with and coaxial with the oil outlet channel 7, the switch valve group is four electromagnetic switch valves which are arranged on the valve body 2, the oil inlet end of the switch valve group is communicated with the square high-pressure oil cavity 16, and the oil outlet end of the switch valve group is communicated with a high-position oil port 13 on the valve sleeve 3.
The width of the second annular groove 14 is larger than the maximum diameter of the high-level oil port 13 on the valve sleeve 3, the sum of the flow areas of the high-level distributing holes 15 in the second annular groove 14 is larger than the sum of the flow areas of the high-level oil port 13, and the diameter of the low-level distributing hole 8 is larger than the maximum diameter of the low-level oil port 9.
As shown in fig. 1 to 4, high-pressure oil flows into the oil inlet channel 12 through the oil inlet a, then flows into the first annular groove 10 on the valve sleeve through the low-level oil hole 11 on the valve body 2, and enters the low-level oil port 9 in the first annular groove 10. The stepping motor 1 drives the valve core 5 to rotate, so that nine flow values can be regulated when the low-level distributing port 8 on the valve core 5 is respectively communicated with nine low-level oil ports 9, and no low-level flow is output when any low-level distributing port 8 is not communicated with any low-level oil ports 9.
The high pressure oil flows into the oil inlet passage 12 through the oil inlet A and then into the square high pressure oil chamber 16 above the valve body. The electromagnetic switch valve 4 is arranged on the valve body 2, an oil inlet of the electromagnetic switch valve is communicated with the square high-pressure oil cavity 16, and an oil outlet of the electromagnetic switch valve is respectively communicated with the high-level oil port 13 on the valve sleeve, so that the on-off state of the four electromagnetic switch valves is controlled, and 24 flow regulation values can be realized.
The high-pressure oil flows into an oil inlet channel 12 through an oil inlet A, then flows into a low-level oil inlet hole 11 on the valve body 2 in two paths, flows into a first annular groove 10 on the valve sleeve, and enters a low-level oil port 9 in the first annular groove; the other way then flows into a square high pressure oil chamber 16 on the valve body 2. When the stepping motor 1 drives the valve core 5 to rotate and the low-level distributing port 8 on the valve core 5 is communicated with any one of nine low-level oil ports in the first annular groove 10, oil in the first annular groove 10 on the valve sleeve 3 flows into the valve core inner cavity 6 through the low-level distributing port 8 on the valve core 5 and flows out of the oil outlet B through the oil outlet channel 7 on the valve body 2, and the area ratio of the nine low-level oil ports 9 in the first annular groove 10 is 1:2:3:4:5:6:7:8:9, the stepper motor can thus control nine discrete flow values. The electromagnetic switch valve group is arranged on the valve body 2, an oil inlet of the electromagnetic switch valve group is communicated with the square high-pressure oil cavity 16, and oil outlets of the electromagnetic switch valve group are respectively communicated with the high-level oil ports 13 on the valve sleeves, and the area ratio of the high-level oil ports 13 is 10:20:40:80. the electromagnetic switch valve 4 is opened, high-pressure oil in the square high-pressure oil cavity 16 flows into the second annular groove 14 on the valve core 5 through the corresponding high-position oil port 13 on the valve sleeve 3, flows into the valve core inner cavity 6 through the high-position distributing hole 15 on the valve core 5, and flows into the oil outlet B through the oil outlet channel 7 on the valve body 2 to flow out. The on-off states of the four electromagnetic switch valves are controlled, so that the change of the high-order flow area interval of 10 from 0 to 150 can be realized. Nine changes of the low-order flow area are matched, and the change of the whole flow area interval 1 from 1 to 159 can be realized. In particular, the stepping motor 1 drives the valve core 5 to ensure that the low-level distributing port 8 is not communicated with nine low-level oil ports, and under the condition that the four electromagnetic switch valves are disconnected, the whole electro-hydraulic digital flow valve has no flow output.
The foregoing has outlined and described the main features, methods of use, basic principles, and advantages of the present invention. It will be understood by those skilled in the art that the present invention is not limited to the above-described embodiments, and that the above-described embodiments and descriptions are merely illustrative of the principles of the present invention, and that various changes and modifications may be made in the invention without departing from the spirit and scope of the invention, which is defined by the appended claims. The scope of the invention is defined by the appended claims and equivalents thereof.
Claims (9)
1. The utility model provides a decimal code electrohydraulic digital flow valve, includes step motor (1), valve body (2), valve pocket (3), switch valves and case (5), step motor (1) is fixed on valve body (2), step motor (1) output shaft with case (5) upper end is connected, case (5) are in valve pocket (3), step motor (1) drive case (5) at valve pocket (3) free rotation, the lower extreme and the valve body (2) clearance fit of case (5), valve pocket (3) and valve body (2) interference fit, characterized in that is provided with low-order hydraulic fluid port (9) and a plurality of including macropore, aperture's shoulder hole on valve pocket (3), wherein the aperture is high-order hydraulic fluid port (13), and the switch valves is installed on valve body (2) for control high-order hydraulic fluid port (13) and the intercommunication state of case inner chamber (6), and low-order hydraulic fluid port (9) and case inner chamber (6) and intercommunication state are realized through the rotation of case (5).
2. A decimal coded electrohydraulic digital flow valve according to claim 1, characterized in that the number of said low-level oil ports (9) is nine, in the shape of round holes or square holes, and the number of said high-level oil ports (13) is not less than 1, in the shape of round holes or square holes.
3. The decimal coded electrohydraulic digital flow valve of claim 1, wherein, the upper end of the said valve core (5) has drive holes connected with output shaft of the stepping motor (1), there are valve core inner cavities (6) internally, the lower end communicates with oil outlet channel (7), the surface has second annular groove (14) and low-position and joins the flow hole (8), there are high-position and joins the flow hole (15) communicating with valve core inner cavity (6) in the said second annular groove (14), said low-position joins the flow hole (8) to communicate with valve core inner cavity (6) directly, the lower outer surface of the valve core (5) and valve block (2) clearance fit, while offering the support for valve core (5), do not influence its free rotation, the outlet of the valve core inner cavity (6) communicates with oil outlet channel (7) on the valve block (2).
4. The decimal-coded electrohydraulic digital flow valve of claim 2, wherein the valve sleeve (3) is of an annular structure, a first annular groove (10) is arranged on the outer surface of the valve sleeve, nine low-level oil ports (9) are uniformly distributed in the first annular groove (10) along the circumferential direction, the flow area ratio of the nine low-level oil ports (9) is 1:2:3:4:5:6:7:8:9, the nine low-level oil ports are consistent with the low-level distributing holes (8) in height, the nine low-level oil ports (9) can be respectively communicated with the low-level distributing holes (8) in the rotating process of the valve core (5), and the high-level oil ports (13) are communicated with a second annular groove (14) on the outer surface of the valve core (5).
5. A decimal coded electrohydraulic digital flow valve as claimed in claim 1, characterized in that a low-level oil inlet hole (11) communicated with the first annular groove (10) is arranged in the oil inlet channel of the valve body (2), four communicated oil channels in the valve body (2) form a square high-pressure oil cavity (16) and are communicated with the oil inlet channel (7) of the valve body, the outlet of the valve core cavity (6) is communicated with and coaxial with the oil outlet channel (7), the switch valve group is composed of a plurality of switch valves (4) arranged on the valve body (2), the oil inlet end of the switch valve group is communicated with the square high-pressure oil cavity (16), and the oil outlet end of the switch valve group is communicated with a high-level oil port (13) on the valve sleeve (3).
6. A decimal coded electrohydraulic digital flow valve according to claim 1, characterized in that the width of the second annular groove (14) is larger than the maximum diameter of the high-order oil port (13) on the valve sleeve (3), the sum of the flow areas of the high-order distributing holes (15) in the second annular groove (14) is larger than the sum of the flow areas of the high-order oil port (13), and the diameter of the low-order distributing hole (8) is larger than the maximum diameter of the low-order oil port (9).
7. A decimal-encoded electro-hydraulic digital flow valve according to claim 6 wherein the number of high-order orifice (15) is at least 1.
8. A decimal coded electrohydraulic digital flow valve according to claim 1, characterized in that the flow area ratio of the high-order oil port (13) is 10 times the binary sequence of the minimum low-order oil port (9) area, namely 10:16:40:80:160: …: 10X 2 n Wherein n represents the number of on-off valves.
9. A decimal coded electrohydraulic digital flow valve according to claim 1, characterized in that the number of said on-off valves (4) is the same as the number of high-order ports (13), said on-off valves (4) being electromagnetic on-off valves or piezoelectric on-off valves.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202310740407.7A CN116771955A (en) | 2023-06-21 | 2023-06-21 | Decimal coded electrohydraulic digital flow valve |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202310740407.7A CN116771955A (en) | 2023-06-21 | 2023-06-21 | Decimal coded electrohydraulic digital flow valve |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| CN116771955A true CN116771955A (en) | 2023-09-19 |
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Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN202310740407.7A Pending CN116771955A (en) | 2023-06-21 | 2023-06-21 | Decimal coded electrohydraulic digital flow valve |
Country Status (1)
| Country | Link |
|---|---|
| CN (1) | CN116771955A (en) |
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2023
- 2023-06-21 CN CN202310740407.7A patent/CN116771955A/en active Pending
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