CN112558645A - High-precision adjustable flow output device - Google Patents
High-precision adjustable flow output device Download PDFInfo
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- CN112558645A CN112558645A CN202011231205.2A CN202011231205A CN112558645A CN 112558645 A CN112558645 A CN 112558645A CN 202011231205 A CN202011231205 A CN 202011231205A CN 112558645 A CN112558645 A CN 112558645A
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- valve
- screw rod
- way valve
- working cavity
- output device
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- G—PHYSICS
- G05—CONTROLLING; REGULATING
- G05D—SYSTEMS FOR CONTROLLING OR REGULATING NON-ELECTRIC VARIABLES
- G05D7/00—Control of flow
- G05D7/06—Control of flow characterised by the use of electric means
- G05D7/0617—Control of flow characterised by the use of electric means specially adapted for fluid materials
- G05D7/0629—Control of flow characterised by the use of electric means specially adapted for fluid materials characterised by the type of regulator means
- G05D7/0635—Control of flow characterised by the use of electric means specially adapted for fluid materials characterised by the type of regulator means by action on throttling means
- G05D7/0641—Control of flow characterised by the use of electric means specially adapted for fluid materials characterised by the type of regulator means by action on throttling means using a plurality of throttling means
- G05D7/0647—Control of flow characterised by the use of electric means specially adapted for fluid materials characterised by the type of regulator means by action on throttling means using a plurality of throttling means the plurality of throttling means being arranged in series
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- G—PHYSICS
- G05—CONTROLLING; REGULATING
- G05D—SYSTEMS FOR CONTROLLING OR REGULATING NON-ELECTRIC VARIABLES
- G05D7/00—Control of flow
- G05D7/06—Control of flow characterised by the use of electric means
- G05D7/0617—Control of flow characterised by the use of electric means specially adapted for fluid materials
- G05D7/0629—Control of flow characterised by the use of electric means specially adapted for fluid materials characterised by the type of regulator means
- G05D7/0635—Control of flow characterised by the use of electric means specially adapted for fluid materials characterised by the type of regulator means by action on throttling means
- G05D7/0641—Control of flow characterised by the use of electric means specially adapted for fluid materials characterised by the type of regulator means by action on throttling means using a plurality of throttling means
- G05D7/0652—Control of flow characterised by the use of electric means specially adapted for fluid materials characterised by the type of regulator means by action on throttling means using a plurality of throttling means the plurality of throttling means being arranged in parallel
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- General Physics & Mathematics (AREA)
- Engineering & Computer Science (AREA)
- Automation & Control Theory (AREA)
- Fluid-Pressure Circuits (AREA)
Abstract
The invention discloses a high-precision flow-adjustable output device which comprises a hydraulic cylinder, a check valve group, a pipeline, a connecting rod, a motor, a rotary table, a nut sliding block, an adjusting nut and a screw rod. When the hydraulic cylinder rod moves rightwards, the piston compresses the right working cavity and enables the oil in the right working cavity to enter the oil discharge pipe through the second one-way valve, and the oil in the oil suction pipe enters the right working cavity through the third one-way valve; the stable flow output of the oil discharge pipe is realized by repeatedly compressing the working cavity leftwards or rightwards through the piston, and the position of the nut sliding block on the screw rod is changed by rotating the adjusting nut and the screw rod, so that the stroke range of the piston moving back and forth in the first cylinder body is changed, and finally the high-precision flow adjustment of the oil discharge pipe is realized.
Description
Technical Field
The invention relates to the technical field of adjustable flow output, in particular to a high-precision adjustable flow output device.
Background
The prior art utilizes a flow valve to perform a certain flow control function on a flow system, for example, a flow regulating device is applied in a pipe network to set flow according to design, the flow valve is regulated through the flow valve, under the action of liquid, the flow valve can automatically eliminate residual pressure heads of pipelines and flow deviation caused by pressure fluctuation, the set flow is kept unchanged no matter how the system pressure changes, the output flow is set at a constant value, the flow output count of the flow valve is changed into simple time count, and the problem of flow output count is effectively solved.
The high-precision flow valve is a multifunctional valve which controls the flow by adopting a high-precision pilot mode, but has a complex structure, is suitable for a pipeline which is distributed with a hydraulic pipe and needs to control the flow and the pressure, keeps the preset flow unchanged, properly reduces the output pressure, and does not influence the flow at the downstream of a main valve even if the pressure at the upstream of the main valve changes. However, in the application process, the output flow precision of the flow valve is not high due to the influence of factors such as output pressure change, leakage and the like. Accordingly, further improvements and improvements are needed in the art.
According to the principle, the constant-speed and accurate-rotating-speed counting motor is adopted as power, so that the accuracy of output flow is further improved, and the high-accuracy flow adjustable output function is expanded by utilizing a method that the working volume of the hydraulic cylinder can be changed, so that the hydraulic output system is suitable for high-accuracy output occasions.
Disclosure of Invention
The invention aims to overcome the defects of the prior art and provide a high-precision adjustable flow output device.
The purpose of the invention is realized by the following technical scheme:
a high-precision flow-adjustable output device mainly comprises a hydraulic cylinder, a check valve group, a pipeline, a connecting rod, a motor, a rotary table, a nut sliding block, an adjusting nut and a screw rod. The hydraulic cylinder includes a cylinder body, a piston, and a cylinder rod. The check valve group comprises at least four check valves, namely a first check valve, a second check valve, a third check valve and a fourth check valve.
Specifically, the piston is arranged in the cylinder body, can move in the cylinder body, and divides the cylinder body into a left working cavity and a right working cavity which are independent. The hydraulic cylinder rod penetrates through the cylinder body and the piston rod, is hinged with one end of the connecting rod, and drives the piston to move in the cylinder body through the connecting rod. The input end of the first one-way valve is connected with the left working cavity, and the output end of the first one-way valve is connected with the oil drain pipe through a pipeline. The input end of the second one-way valve is connected with the right working cavity, and the output end of the second one-way valve is connected with the oil drain pipe through a pipeline. The input end of the third one-way valve is connected with the oil suction pipe through a pipeline, and the output end of the third one-way valve is connected with the left working cavity. The input end of the fourth one-way valve is connected with the oil suction pipe through a pipeline, and the output end of the fourth one-way valve is connected with the right working cavity.
Specifically, the motor is fixedly connected with the center of the turntable through a motor shaft and drives the turntable to rotate. The turntable is provided with a guide groove, and the guide groove penetrates through the center of the turntable. The screw rod is arranged in the guide groove, one end of the screw rod is fixed, the other end of the screw rod is connected with the adjusting nut, and the screw rod can be driven to rotate through the adjusting nut. The nut sliding block is arranged on the screw rod and changes the distance between the nut sliding block and the center of the rotary table along with the rotation of the screw rod. The other end of the connecting rod is rotatably connected with the nut sliding block.
Furthermore, the high-precision adjustable flow output device also comprises a joint and an overflow valve for controlling the oil pressure at the end of the oil drain pipe. One end of the joint is connected with the oil drain pipe, and the other end of the joint is connected with the overflow valve.
As a preferable aspect of the present invention, the check valve mainly includes a first valve body, a valve spool, and a first spring. One end of the first valve body is provided with an input port, and the other end of the first valve body is provided with an output port. One end of the valve core is connected with the input port in an abutting mode, and the other end of the valve core is connected with the output port in an abutting mode through a first spring.
As a preferable scheme of the invention, the overflow valve mainly comprises a second valve body, a spring pressing block, and a steel ball, a steel ball pressing block and a second spring which are arranged in the second valve body. The input end of the second valve body is connected with the oil drain pipe, and the output end of the second valve body is connected with the outside or other pipelines. And the spring pressing block is arranged at the end part of the second valve body and is opposite to the input end of the second valve body. The steel ball is arranged on the steel ball pressing block, and the steel ball pressing block is pressed on the input end of the second valve body by one end of the second spring. The other end of the second spring is abutted against the spring pressing block.
As the preferred scheme of the invention, the left working cavity and the right working cavity are designed by adopting a symmetrical structure.
In a preferred embodiment of the present invention, the motor is a stepping motor or a servo motor.
The working process and principle of the invention are as follows: when the hydraulic cylinder rod moves rightwards, the piston compresses a right working cavity (the first one-way valve and the fourth one-way valve are closed, the second one-way valve and the third one-way valve are opened) and enables oil in the right working cavity to enter an oil discharge pipe through the first one-way valve; the stable flow output of the oil discharge pipe is realized by repeatedly compressing the working cavity leftwards or rightwards through the piston, and the position of the nut sliding block on the screw rod is changed by rotating the adjusting nut and the screw rod, so that the stroke range of the piston moving back and forth in the first cylinder body is changed, and finally the high-precision flow adjustment of the oil discharge pipe is realized. The invention also has the advantages of simple structure, convenient operation and easy implementation.
Compared with the prior art, the invention also has the following advantages:
(1) the high-precision flow output device with the adjustable flow can adjust the flow output within a certain range, and meets the required output flow.
(2) The high-precision flow-adjustable output device provided by the invention is driven by a stepping motor or a servo motor, can accurately control the output of flow, can count the flow by the time length of common flow output, can count by adopting the revolution number of the stepping motor or the servo motor, and has the advantage of high flow counting precision.
Drawings
Fig. 1 is a schematic structural diagram of a high-precision adjustable flow output device provided by the invention.
Fig. 2 is a schematic diagram of a flow regulating structure provided by the present invention.
Fig. 3 is a schematic structural diagram of the check valve provided by the present invention.
Fig. 4 is a schematic structural diagram of the relief valve provided by the present invention.
The reference numerals in the above figures illustrate:
1-hydraulic cylinder, 2-one-way valve, 21-first valve body, 22-valve core, 23-first spring, 24-first one-way valve, 25-second one-way valve, 26-third one-way valve, 27-fourth one-way valve, 3-pipeline, 4-oil drain pipe, 5-joint, 6-overflow valve, 61-steel ball, 62-second valve body, 63-steel ball press block, 64-second spring, 65-spring press block, 7-hydraulic cylinder rod, 8-motor shaft, 9-rotary table, 10-screw rod, 11-nut slide block, 12-adjusting nut, 13-connecting rod, 14-piston, 15-oil suction pipe and 16-guide groove.
Detailed Description
In order to make the objects, technical solutions and advantages of the present invention clearer and clearer, the present invention is further described below with reference to the accompanying drawings and examples.
Example 1:
as shown in fig. 1 to 4, the present embodiment discloses a high-precision adjustable flow output device, which mainly includes a hydraulic cylinder 1, a check valve set, a pipeline 3, a connecting rod 13, a motor, a rotary table 9, a nut slider 11, an adjusting nut 12, and a screw rod 10. The hydraulic cylinder 1 comprises a cylinder body, a piston 14, and a cylinder rod 7. The check valve group comprises at least four check valves 2, namely a first check valve 24, a second check valve 25, a third check valve 26 and a fourth check valve 27.
Specifically, the piston 14 is disposed in the cylinder body, can move in the cylinder body, and divides the cylinder body into a left working chamber and a right working chamber. The hydraulic cylinder rod 7 penetrates through the cylinder body and the piston 14 rod, is hinged with one end of the connecting rod 13, and drives the piston 14 to move in the cylinder body through the connecting rod 13. The input end of the first one-way valve 24 is connected with the left working cavity, and the output end of the first one-way valve is connected with the oil drain pipe 4 through the pipeline 3. The input end of the second one-way valve 25 is connected with the right working cavity, and the output end of the second one-way valve is connected with the oil drain pipe 4 through the pipeline 3. The input end of the third one-way valve 26 is connected with the oil suction pipe 15 through the pipeline 3, and the output end is connected with the left working cavity. The input end of the fourth one-way valve 27 is connected with the oil suction pipe 15 through the pipeline 3, and the output end is connected with the right working cavity.
Specifically, the motor is fixedly connected with the center of the turntable 9 through a motor shaft 8, and drives the turntable 9 to rotate. The turntable 9 is provided with a guide groove 16, and the guide groove 16 penetrates through the center of the turntable 9. The screw rod 10 is arranged in the guide groove 16, one end of the screw rod is fixed, the other end of the screw rod is connected with the adjusting nut 12, and the screw rod 10 can be driven to rotate through the adjusting nut 12. The nut sliding block 11 is arranged on the screw rod 10, and changes the distance between the nut sliding block and the center of the rotary table 9 along with the rotation of the screw rod 10. The other end of the connecting rod 13 is rotatably connected with the nut sliding block 11.
Furthermore, the high-precision adjustable flow output device also comprises a joint 5 and an overflow valve 6 for controlling the oil pressure at the end of the oil drain pipe 4. One end of the joint 5 is connected with the oil drain pipe 4, and the other end of the joint is connected with the overflow valve 6.
As a preferable aspect of the present invention, the check valve 2 mainly includes a first valve body 21, a spool 22, and a first spring 23. One end of the first valve body 21 is provided with an input port, and the other end is provided with an output port. One end of the valve core 22 abuts against the input port, and the other end abuts against the output port through a first spring 23.
As a preferable embodiment of the present invention, the relief valve 6 mainly includes a second valve body 62, a spring pressing block 65, and a steel ball 61, a steel ball pressing block 63, and a second spring 64 provided in the second valve body 62. The input end of the second valve body 62 is connected with the oil drain pipe 4, and the output end is connected with the outside or other pipelines. The spring pressing piece 65 is installed at the end of the second valve body 62 opposite to the input end of the second valve body 62. The steel ball 61 is mounted on a steel ball press 63, and the steel ball press 63 is pressed against the input end of the second valve body 62 by one end of a second spring 64. The other end of the second spring 64 abuts against the spring pressing block 65.
As the preferred scheme of the invention, the left working cavity and the right working cavity are designed by adopting a symmetrical structure.
In a preferred embodiment of the present invention, the motor is a stepping motor or a servo motor.
The working process and principle of the invention are as follows: when the hydraulic oil pumping device works, the motor drives the rotary table 9 to rotate, the nut slide block 11 attached to the rotary table 9 rotates along with the rotary table 9, meanwhile, the hydraulic cylinder rod 7 is driven to move left and right through the connecting rod, when the hydraulic cylinder rod 7 moves left, the piston 14 compresses a left working cavity (the first one-way valve 24 and the fourth one-way valve 27 are opened, the second one-way valve 25 and the third one-way valve 26 are closed), oil in the left working cavity enters the oil drain pipe 4 through the first one-way valve 24, oil in the oil suction pipe 15 enters a right working cavity through the fourth one-way valve 27, when the hydraulic cylinder rod 7 moves right, the piston 14 compresses a right working cavity (the first one-way valve 24 and the fourth one-way valve 27 are closed, the second one-way valve 25 and the third one-way valve 26 are opened) and oil in the right working cavity enters the oil drain pipe 4 through the second one-way valve 25, and oil in the oil; the stable flow output of the oil drain pipe 4 is realized by repeatedly compressing the working cavity leftwards or rightwards through the piston 14, and the position of the nut slider 11 on the screw rod 10 is changed by rotating the adjusting nut 12 and the screw rod 10, so that the stroke range of the piston 14 moving back and forth in the first cylinder body is changed, and finally the high-precision flow adjustment of the oil drain pipe 4 is realized. The invention also has the advantages of simple structure, convenient operation and easy implementation.
Example 2:
the embodiment discloses an adjustable flow output device, and this adjustable flow output device mainly includes:
the flow-adjustable output device is driven by a motor, a motor shaft 8 is arranged at the rotating center of the turntable 9, and the motor is a stepping motor or a servo motor so as to improve the accuracy of output flow.
A guide groove 16 is formed in one side of the rotary table 9, a nut screw rod 10 mechanism is arranged in the guide groove 16, the movement of the sliding block can be adjusted through the nut screw rod 10, and when the screw rod 10 rotates, the nut can move towards the center or the edge of the rotary table 9 along the guide groove 16.
One end of the connecting rod 13 is connected with the sliding block and can rotate relatively, the other end of the connecting rod is connected with the hydraulic cylinder rod 7, when the motor drives the connecting rod 13 to move, the connecting rod 13 also drives the piston rod to move left and right, and the flow control system is assisted with 4 one-way valves 2 to realize the output of the liquid flow of the hydraulic cylinder 1.
The check valves 2 are the check valves 2 with the same structure, the valve cores 22 of the 2 check valves 2 on the hydraulic cylinder 1 are placed downwards, and the valve cores 22 of the two check valves 2 below the hydraulic cylinder 1 are placed upwards.
The left and right working cavities of the adjustable flow output hydraulic cylinder 1 have symmetrical structures, and one end of the adjustable flow output hydraulic cylinder is hinged with the connecting rod 13 and can move relatively.
The output end of the adjustable flow output device is provided with an overflow valve 6, and the overflow valve 6 can set the outlet pressure and limit the outlet pressure within a certain range.
The two one-way valves 2 at the lower end of the hydraulic cylinder 1 of the flow-adjustable output device are connected in parallel and are connected with an oil suction pipe 15, so that the oil suction function is realized.
Two check valves 2 at the upper end of a hydraulic cylinder 1 of the adjustable flow output device are connected in parallel and connected with an oil drain pipe 4, so that the oil drain function is realized.
The adjustable flow output device is provided with a nut screw rod 10 mechanism, a nut in an adjustable nut screw rod 12 and a sliding block fixed on the nut, the screw rod 10 is rotated, the sliding block on the nut can be driven to move towards the center of the rotary table 9 or the edge of the rotary table 9, the stroke of the hydraulic cylinder 1 can be changed by the sliding block at different positions on the rotary table 9, and the flow of the hydraulic cylinder 1 in one stroke period can be adjusted.
As a preferable aspect of the present invention, the adjustable flow output device turntable 9 rotates at a constant rotation speed to keep the flow output stable, and when the flow output needs to be adjusted, the slider position is adjusted when the motor is stopped.
As a preferable aspect of the present invention, the check valve 2 at the left end or the right end of the hydraulic cylinder 1 of the adjustable flow output device may share one opening of the hydraulic cylinder 1, and it is not necessary to provide two openings at one side of the hydraulic cylinder 1.
As a preferred scheme of the invention, the pressure regulation size of the overflow valve 6 of the flow-adjustable output device needs to be matched with the driving capability of the motor, so that the insufficient or waste of the motor capability is avoided.
As a preferable scheme of the present invention, the adjustable flow output device adjusts the flow output by the position of a slide block on the turntable 9, the position of the slide block is adjusted by a nut screw 10 mechanism, when accurate flow counting is performed, the position of the slide block needs to be fixed, and the nut screw 10 has a self-locking capability.
Furthermore, an oil inlet and an oil outlet of the adjustable flow output device are strictly distinguished.
The above embodiments are preferred embodiments of the present invention, but the present invention is not limited to the above embodiments, and any other changes, modifications, substitutions, combinations, and simplifications which do not depart from the spirit and principle of the present invention should be construed as equivalents thereof, and all such changes, modifications, substitutions, combinations, and simplifications are intended to be included in the scope of the present invention.
Claims (6)
1. A high-precision flow-adjustable output device is characterized by comprising a hydraulic cylinder, a check valve group, a pipeline, a connecting rod, a motor, a rotary table, a nut sliding block, an adjusting nut and a screw rod; the hydraulic cylinder comprises a cylinder body, a piston and a hydraulic cylinder rod; the check valve group comprises at least four check valves which are respectively a first check valve, a second check valve, a third check valve and a fourth check valve;
the piston is arranged in the cylinder body, can move in the cylinder body and divides the cylinder body into a left working cavity and a right working cavity which are independent; the hydraulic cylinder rod penetrates through the cylinder body and the piston rod, is hinged with one end of the connecting rod, and drives the piston to move in the cylinder body through the connecting rod; the input end of the first one-way valve is connected with the left working cavity, and the output end of the first one-way valve is connected with the oil drain pipe through a pipeline; the input end of the second one-way valve is connected with the right working cavity, and the output end of the second one-way valve is connected with the oil drain pipe through a pipeline; the input end of the third one-way valve is connected with the oil suction pipe through a pipeline, and the output end of the third one-way valve is connected with the left working cavity; the input end of the fourth one-way valve is connected with the oil suction pipe through a pipeline, and the output end of the fourth one-way valve is connected with the right working cavity;
the motor is fixedly connected with the center of the turntable through a motor shaft and drives the turntable to rotate; the turntable is provided with a guide groove which passes through the center of the turntable; the screw rod is arranged in the guide groove, one end of the screw rod is fixed, the other end of the screw rod is connected with the adjusting nut, and the screw rod can be driven to rotate through the adjusting nut; the nut sliding block is arranged on the screw rod and changes the distance from the center of the rotary table along with the rotation of the screw rod; the other end of the connecting rod is rotatably connected with the nut sliding block.
2. The high-precision adjustable flow output device according to claim 1, further comprising a joint and an overflow valve for controlling oil pressure at the end of the oil drain; one end of the joint is connected with the oil drain pipe, and the other end of the joint is connected with the overflow valve.
3. The high precision adjustable flow output device of claim 1, wherein the one-way valve comprises a first valve body, a valve spool, and a first spring; one end of the first valve body is provided with an input port, and the other end of the first valve body is provided with an output port; one end of the valve core is connected with the input port in an abutting mode, and the other end of the valve core is connected with the output port in an abutting mode through a first spring.
4. The high-precision adjustable flow output device according to claim 2, wherein the overflow valve comprises a second valve body, a spring pressing block, and a steel ball, a steel ball pressing block and a second spring which are arranged in the second valve body; the input end of the second valve body is connected with the oil drain pipe, and the output end of the second valve body is connected with the outside or other pipelines; the spring pressing block is arranged at the end part of the second valve body and is opposite to the input end of the second valve body; the steel ball is arranged on a steel ball pressing block, and the steel ball pressing block is pressed on the input end of the second valve body by one end of a second spring; the other end of the second spring is abutted against the spring pressing block.
5. The high precision adjustable flow output device according to claim 1, wherein the left and right working chambers are designed with a symmetrical structure.
6. The high precision adjustable flow output device according to claim 1, wherein the motor is a stepper motor or a servo motor.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202011231205.2A CN112558645A (en) | 2020-11-06 | 2020-11-06 | High-precision adjustable flow output device |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202011231205.2A CN112558645A (en) | 2020-11-06 | 2020-11-06 | High-precision adjustable flow output device |
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| CN112558645A true CN112558645A (en) | 2021-03-26 |
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| Application Number | Title | Priority Date | Filing Date |
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| CN202011231205.2A Pending CN112558645A (en) | 2020-11-06 | 2020-11-06 | High-precision adjustable flow output device |
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Cited By (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN113896160A (en) * | 2021-11-19 | 2022-01-07 | 固安恒拓包装设备有限公司 | Quantitative filling structure and quantitative filling device |
-
2020
- 2020-11-06 CN CN202011231205.2A patent/CN112558645A/en active Pending
Cited By (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN113896160A (en) * | 2021-11-19 | 2022-01-07 | 固安恒拓包装设备有限公司 | Quantitative filling structure and quantitative filling device |
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