CN111981171A - Diaphragm feedback type hydraulic constant flow control block - Google Patents
Diaphragm feedback type hydraulic constant flow control block Download PDFInfo
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- CN111981171A CN111981171A CN202010895242.7A CN202010895242A CN111981171A CN 111981171 A CN111981171 A CN 111981171A CN 202010895242 A CN202010895242 A CN 202010895242A CN 111981171 A CN111981171 A CN 111981171A
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- F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
- F16—ENGINEERING ELEMENTS AND UNITS; GENERAL MEASURES FOR PRODUCING AND MAINTAINING EFFECTIVE FUNCTIONING OF MACHINES OR INSTALLATIONS; THERMAL INSULATION IN GENERAL
- F16K—VALVES; TAPS; COCKS; ACTUATING-FLOATS; DEVICES FOR VENTING OR AERATING
- F16K17/00—Safety valves; Equalising valves, e.g. pressure relief valves
- F16K17/20—Excess-flow valves
- F16K17/22—Excess-flow valves actuated by the difference of pressure between two places in the flow line
- F16K17/24—Excess-flow valves actuated by the difference of pressure between two places in the flow line acting directly on the cutting-off member
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Abstract
The invention discloses a diaphragm feedback type hydraulic constant flow control block, and relates to a flow and pressure regulating device. The flow control block can control the throttling effect of the throttling device by the diaphragm deformation quantity, and realize automatic feedback and constant flow of different loads of the hydrostatic element by combining the fixed throttling effect of the gap throttling device. The flow control block comprises a flow block shell and a throttling block, wherein an elastic diaphragm is arranged between the flow block shell and the throttling block, an oil inlet hole, an oil outlet hole and a transition oil inlet hole are formed in the throttling block, the oil inlet hole is communicated with the lower portion of the elastic diaphragm through an oil inlet gap, the oil outlet hole is communicated with the upper portion of the elastic diaphragm, a feedback oil inlet gap is formed between the bottom of the throttling block and the elastic diaphragm, the transition oil inlet hole penetrates through the interior of the throttling block to be communicated with the feedback oil inlet gap, a first throttling groove and a second throttling groove which are communicated are formed in the upper end face of the throttling block, the oil inlet hole and the transition oil inlet hole are communicated with the first throttling groove, and the oil outlet hole is communicated.
Description
Technical Field
The invention relates to the technical field of flow and pressure regulation, in particular to a diaphragm feedback type hydraulic constant flow control block.
Background
Hydraulic technology has become very popular for use in various mechanical devices, and in hydraulic technology, restrictors are widely used in hydrostatic technology. The hydrostatic restrictor has various structural forms, including a small-hole restrictor, a capillary restrictor, a slit restrictor and a feedback restrictor, wherein the feedback restrictor comprises a fixed feedback restrictor and a dynamic feedback restrictor, and the dynamic feedback restrictor mainly comprises a slide valve feedback restrictor and a film feedback restrictor. The diaphragm feedback type hydraulic constant flow block is a principle application of a film feedback type restrictor, the internal structure of the diaphragm feedback type hydraulic constant flow block is complex, the frequency response problem exists, and the research application of the diaphragm feedback type hydraulic constant flow block in the found reference document is less. The hydrostatic throttler which is generally most widely used is a small hole throttler and a gap throttler, and realizes throttling control by adjusting the diameter of a small hole and the size of a gap so as to ensure constant hydraulic flow. However, the adjusting method is mainly to obtain the diameter of the small hole and the size of the gap required by a specific load through theoretical calculation and combined experiments, and the constant flow or the constant pressure of the hydrostatic element cannot be automatically adjusted according to the change of the load after the adjustment is finished.
Disclosure of Invention
The technical problem to be solved by the invention is to provide a diaphragm feedback type hydraulic constant flow control block which can control the throttling effect of a throttling device by diaphragm deformation, realizes automatic feedback and constant flow of different loads of a hydrostatic element by combining the fixed throttling effect of a gap throttling device, and has the advantages of simple structure, small volume size, reliable control flow and simple use method.
The invention relates to a diaphragm feedback type hydraulic constant flow control block which comprises a flow block shell and a throttle block, wherein the throttle block is arranged in the flow block shell, an elastic diaphragm is arranged on a matching end surface between the flow block shell and the bottom of the throttle block, an oil inlet hole, an oil outlet hole and a transition oil inlet hole are formed in the throttle block, the oil inlet hole is communicated with the lower part of the elastic diaphragm through an oil inlet gap in the side wall of the throttle block, the oil outlet hole penetrates through the inside of the throttle block to be communicated with the upper part of the elastic diaphragm, a feedback oil inlet gap is formed between the bottom of the throttle block and the elastic diaphragm, the transition oil inlet hole penetrates through the inside of the throttle block to be communicated with the feedback oil inlet gap, a first throttle groove and a second throttle groove which are communicated are formed in the upper end surface of the throttle block, the oil inlet hole and the transition oil inlet hole are communicated with the first throttle.
The invention relates to a diaphragm feedback type hydraulic constant flow control block, wherein a boss is processed on the lower end face of a throttling block, a feedback oil inlet gap is positioned between the end face of the boss and an elastic diaphragm, and long holes are processed on the throttling block and the boss for communicating an oil outlet with the feedback oil inlet gap.
The invention relates to a diaphragm feedback type hydraulic constant flow control block, wherein the outer ring of the lower end face of a throttling block outside a boss is in pressing contact with an elastic diaphragm.
The invention relates to a diaphragm feedback type hydraulic constant flow control block, wherein a first annular oil groove and a second annular oil groove are processed on the lower end face of a throttling block, the first annular oil groove is positioned between a boss and a lower end face outer ring of the throttling block, the second annular oil groove is positioned inside the lower end face outer ring of the throttling block, an oil groove is arranged between the first annular oil groove and the second annular oil groove to communicate the first annular oil groove and the second annular oil groove, and a transition oil inlet hole penetrates through the inside of the throttling block to communicate with the second annular oil groove.
The invention relates to a diaphragm feedback type hydraulic constant flow control block, wherein a transition oil inlet hole is positioned in a first groove, the upper surface of the first groove and the upper end surface of a throttling block are positioned on the same plane, and the first groove is communicated with a first throttling groove and a second throttling groove; the oil outlet is positioned in the second groove, the upper surface of the second groove and the upper end surface of the throttling block are positioned on the same plane, and the second groove is communicated with the second throttling groove and the oil outlet; the oil inlet hole is located in the third groove, the upper surface of the third groove and the upper end face of the throttling block are located on the same plane, and the third groove is communicated with the oil inlet hole and the first throttling groove.
The invention relates to a diaphragm feedback type hydraulic constant flow control block, wherein a notch is processed on the side surface of a throttling block, and an oil inlet gap is defined by the notch and the inner wall of a flow block shell.
The invention relates to a diaphragm feedback type hydraulic constant flow control block, wherein an annular groove is processed above a flow block shell, an O-shaped sealing ring is arranged in the annular groove, the annular groove is contacted with the outer ring of the O-shaped sealing ring, and the side wall of the upper part of a throttling block is contacted with the inner ring of the O-shaped sealing ring.
The invention relates to a diaphragm feedback type hydraulic constant flow control block, wherein an inner hole is processed in a flow block shell, a throttling block is arranged in the inner hole of the flow block shell, and the flow block shell and the throttling block are connected in an interference fit manner.
The invention relates to a diaphragm feedback type hydraulic constant flow control block, wherein a first throttling groove and a second throttling groove are both annular grooves.
The diaphragm feedback type hydraulic constant flow control block is different from the prior art in that the diaphragm feedback type hydraulic constant flow control block is provided with an elastic diaphragm, and the deformation amount of the elastic diaphragm is used for controlling the throttling effect of the throttling device. Hydraulic oil enters the control block from the oil inlet hole and the transition oil inlet hole, finally reaches the upper part and the lower part of the elastic diaphragm respectively, applies pressure to the elastic diaphragm, and combines the elastic deformation force of the elastic diaphragm to form dynamic feedback, so that the throttling effect is achieved. In addition, the control block is also provided with a first throttling groove and a second throttling groove, and the automatic feedback and constant flow of different loads of the hydrostatic element are realized by combining the fixed throttling effect of the gap throttling device and the fixed throttling of the two stages of throttling grooves.
The diaphragm feedback type hydraulic constant flow control block of the present invention will be further described with reference to the accompanying drawings.
Drawings
FIG. 1 is a schematic structural diagram of a diaphragm feedback type hydraulic constant flow control block according to the present invention;
FIG. 2 is a top view of a diaphragm feedback hydraulic constant flow control block according to the present invention;
3 FIG. 3 3 3 is 3 a 3 sectional 3 view 3 taken 3 along 3 line 3 A 3- 3 A 3 in 3 FIG. 3 2 3; 3
FIG. 4 is a sectional view taken along line B-B of FIG. 2;
FIG. 5 is a front view of a throttle block in a diaphragm feedback hydraulic constant flow control block according to the present invention;
FIG. 6 is a rear view of a throttle block in a diaphragm feedback hydraulic constant flow control block according to the present invention;
the notation in the figures means: 1-a flow block housing; 2-a throttling block; 3-an elastic membrane; 4-O type sealing ring; 5-oil outlet; 6-oil inlet hole; 7-a first throttling groove; 8-a second throttling groove; 9-oil inlet gap; 10-feeding back an oil inlet gap; 11-a first annular oil groove; 12-a second annular oil groove; 13-transition oil inlet hole.
Detailed Description
The following examples are intended to illustrate the invention but are not intended to limit the scope of the invention.
As shown in fig. 1, a diaphragm feedback type hydraulic constant flow control block of the present invention is a diaphragm feedback type hydrostatic restrictor structure, and has functions of automatic feedback and constant flow for different load sizes of hydrostatic components.
As shown in fig. 1-3, a diaphragm feedback type hydraulic constant flow control block according to the present invention includes a flow block housing 1 and a throttle block 2. An inner hole is processed in the flow block shell 1, an annular groove is processed above the flow block shell 1, an O-shaped sealing ring 4 is installed in the annular groove, and the annular groove is in contact with the outer ring of the O-shaped sealing ring 4. The throttling block 2 is arranged in an inner hole of the flow block shell 1, and the flow block shell 1 and the throttling block 2 are connected through interference fit. The side wall of the upper part of the throttling block 2 is contacted with the inner ring of the O-shaped sealing ring 4. The elastic membrane 3 is pressed on the matching end surface between the flow block shell 1 and the bottom of the throttle block 2.
As shown in fig. 4-6, the throttle block 2 is provided with an oil inlet 6 and an oil outlet 5. The oil inlet hole 6 is positioned at the edge position of the upper end surface of the throttle block 2. A notch is formed in the side face of the throttling block 2, a downward oil inlet gap 9 is formed between the notch and the inner wall of the flow block shell 1, and the oil inlet hole 6 is communicated with the oil inlet gap 9. The elastic membrane 3 is provided with a through hole, and the position of the through hole is opposite to the oil inlet gap 9. Hydraulic oil can enter from the oil inlet 6, and enters into the gap between the elastic diaphragm 3 and the flow block shell 1 through the oil inlet gap 9 and the through hole on the elastic diaphragm 3. A boss extending downwards is processed on the lower end face of the throttling block 2, and a gap is reserved between the end face of the boss and the elastic membrane 3 and is used for feeding oil into the gap 10. The oil outlet 5 is positioned in the middle of the upper end surface of the throttling block 2, and a long hole is processed at the oil outlet 5 and penetrates through the throttling block 2 and the boss from top to bottom. The outer ring of the lower end surface of the throttling block 2 outside the boss is in pressing contact with the elastic membrane 3. The hydraulic oil discharged from the oil outlet 5 provides pressure for a hydraulic slide block of the hydraulic system.
The upper end surface of the throttling block 2 is provided with a first throttling groove 7 and a second throttling groove 8, and both the two throttling grooves are annular grooves. A transition oil inlet hole 13 is formed in the first throttling groove 7, and the transition oil inlet hole 13 is located in the first groove. The upper surface of the first groove and the upper end surface of the throttling block 2 are positioned on the same plane, and the first groove is communicated with a first throttling groove 7 and a second throttling groove 8. The oil outlet 5 is positioned in the second groove, the upper surface of the second groove and the upper end surface of the throttling block 2 are positioned on the same plane, and the second groove is communicated with the second throttling groove 8 and the oil outlet 5. The oil inlet hole 6 is positioned in the third groove, the upper surface of the third groove and the upper end surface of the throttling block 2 are positioned on the same plane, and the third groove is communicated with the oil inlet hole 6 and the first throttling groove 7.
The lower terminal surface of throttle piece 2 has first annular oil groove 11 and second annular oil groove 12, and first annular oil groove 11 is located between the boss and the lower extreme surface of throttle piece 2 encloses, and second annular oil groove 12 is located inside the lower extreme surface of throttle piece 2 encloses, has an oil groove between first annular oil groove 11 and the second annular oil groove 12 and is linked together both. A long hole is processed at the transition oil inlet hole 13 and is communicated with the second annular oil groove 12.
When the diaphragm feedback type hydraulic constant flow control block is used, after the diaphragm feedback type hydraulic constant flow control block is connected with a hydrostatic pressure element, hydraulic oil enters from an oil inlet 6 and is divided into two parts: one part of hydraulic oil enters the oil inlet gap 9, and the other part of hydraulic oil reaches the transition oil inlet hole 13 through the first throttling groove 7;
the hydraulic oil entering the oil inlet gap 9 reaches the lower part of the elastic membrane 3, and the middle of the elastic membrane 3 protrudes upwards under the pressure action of the hydraulic oil;
the hydraulic oil entering the transition oil inlet 13 is divided into two parts: one part of hydraulic oil enters the second throttling groove 8, and the other part of hydraulic oil enters the second annular oil groove 12 at the bottom of the throttling block 2 and then enters the first annular oil groove 11;
the hydraulic oil entering the second annular oil groove 12 reaches the upper part of the elastic diaphragm 3, and the middle of the elastic diaphragm 3 is sunken downwards under the pressure action of the hydraulic oil;
the hydraulic oil entering the first annular oil groove 11 passes through the feedback oil inlet gap 10 between the bottom of the throttle and the elastic diaphragm 3, so that the hydraulic oil reaches the oil outlet 5, the oil outlet 5 is connected with the load of the hydrostatic element, the load of the hydrostatic element is different, and the pressure value of the oil outlet 5 is different. The middle of the elastic diaphragm 3 protrudes upwards or sinks downwards under the action of the pressure of the hydraulic oil at the lower part and the upper part, and due to the fact that the pressure of the hydraulic oil at the bottom part and the pressure of the hydraulic oil at the top part are inconsistent, dynamic feedback is formed by combining the elastic deformation force of the elastic diaphragm 3, the matching balance of the load of the hydrostatic element and the pressure value of the oil outlet 5 is automatically adjusted, and the purpose of constant flow control is achieved.
The diaphragm feedback type hydraulic constant flow control block is provided with an elastic diaphragm, and the throttling effect of the throttling device is controlled by the deformation amount of the elastic diaphragm. Hydraulic oil enters the control block from the oil inlet hole and the transition oil inlet hole, finally reaches the upper part and the lower part of the elastic diaphragm respectively, applies pressure to the elastic diaphragm, and combines the elastic deformation force of the elastic diaphragm to form dynamic feedback, so that the throttling effect is achieved. In addition, the control block is also provided with a first throttling groove and a second throttling groove, and the automatic feedback and constant flow of different loads of the hydrostatic element are realized by combining the fixed throttling effect of the gap throttling device and the fixed throttling of the two stages of throttling grooves.
Although the invention has been described in detail above with reference to a general description and specific examples, it will be apparent to one skilled in the art that modifications or improvements may be made thereto based on the invention. Accordingly, such modifications and improvements are intended to be within the scope of the invention as claimed.
Claims (9)
1. A diaphragm feedback type hydraulic constant flow control block is characterized in that: the throttling block is arranged inside the flow block shell, an elastic diaphragm is arranged on a matching end face between the flow block shell and the bottom of the throttling block, an oil inlet hole, an oil outlet hole and a transition oil inlet hole are formed in the throttling block, the oil inlet hole is communicated with the lower portion of the elastic diaphragm through an oil inlet gap in the side wall of the throttling block, the oil outlet hole penetrates through the inside of the throttling block and is communicated with the upper portion of the elastic diaphragm, a feedback oil inlet gap is formed between the bottom of the throttling block and the elastic diaphragm, the transition oil inlet hole penetrates through the inside of the throttling block and is communicated with the feedback oil inlet gap, a first throttling groove and a second throttling groove which are communicated are formed in the upper end face of the throttling block, the oil inlet hole and the transition oil inlet hole are communicated with the first throttling groove, and the oil outlet hole is communicated with the second.
2. The diaphragm feedback hydraulic constant flow control block according to claim 1, wherein: processing has the boss on the lower terminal surface of throttle piece, the feedback oil feed gap is located between the terminal surface and the elastic diaphragm of boss, and processing has the slot hole to be used for making oil outlet and feedback oil feed gap intercommunication on throttle piece and the boss.
3. The diaphragm feedback hydraulic constant flow control block according to claim 2, wherein: and the outer ring of the lower end face of the throttling block outside the boss is in pressing contact with the elastic membrane.
4. The diaphragm feedback hydraulic constant flow control block according to claim 3, wherein: the lower terminal surface processing of throttle piece has first annular oil groove and second annular oil groove, and first annular oil groove is located between the lower extreme surface outer lane of boss and throttle piece, and second annular oil groove is located inside the lower extreme surface outer lane of throttle piece, has an oil groove to be linked together both between first annular oil groove and the second annular oil groove, the transition inlet port passes inside the throttle piece and communicates with each other with second annular oil groove.
5. The diaphragm feedback hydraulic constant flow control block according to claim 1, wherein: the transition oil inlet hole is positioned in the first groove, the upper surface of the first groove and the upper end surface of the throttling block are positioned on the same plane, and the first groove is communicated with the first throttling groove and the second throttling groove; the oil outlet is positioned in the second groove, the upper surface of the second groove and the upper end surface of the throttling block are positioned on the same plane, and the second groove is communicated with the second throttling groove and the oil outlet; the oil inlet hole is located in the third groove, the upper surface of the third groove and the upper end face of the throttling block are located on the same plane, and the third groove is communicated with the oil inlet hole and the first throttling groove.
6. The diaphragm feedback hydraulic constant flow control block according to claim 1, wherein: a notch is formed in the side face of the throttling block, and an oil inlet gap is formed by the notch and the inner wall of the flow block shell in a surrounding mode.
7. The diaphragm feedback hydraulic constant flow control block according to claim 1, wherein: an annular groove is machined above the flow block shell, an O-shaped sealing ring is installed in the annular groove, the annular groove is in contact with the outer ring of the O-shaped sealing ring, and the side wall of the upper portion of the throttling block is in contact with the inner ring of the O-shaped sealing ring.
8. The diaphragm feedback hydraulic constant flow control block according to claim 1, wherein: an inner hole is processed in the flow block shell, the throttling block is installed in the inner hole of the flow block shell, and the flow block shell and the throttling block are connected in an interference fit mode.
9. The diaphragm feedback hydraulic constant flow control block according to claim 1, wherein: the first throttling groove and the second throttling groove are both annular grooves.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202010895242.7A CN111981171B (en) | 2020-08-31 | 2020-08-31 | Diaphragm feedback type hydraulic constant flow control block |
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| Application Number | Priority Date | Filing Date | Title |
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| CN202010895242.7A CN111981171B (en) | 2020-08-31 | 2020-08-31 | Diaphragm feedback type hydraulic constant flow control block |
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| CN111981171A true CN111981171A (en) | 2020-11-24 |
| CN111981171B CN111981171B (en) | 2022-03-08 |
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Cited By (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN114483787A (en) * | 2021-12-30 | 2022-05-13 | 浙江杭机股份有限公司 | Novel hydrostatic bearing |
Citations (5)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| GB1017921A (en) * | 1961-05-09 | 1966-01-26 | English Electric Co Ltd | Shaft seal |
| CN102691723A (en) * | 2011-12-17 | 2012-09-26 | 河南科技大学 | Thin film feedback throttling device module, static bearing module and main spindle box module |
| CN106763882A (en) * | 2017-03-08 | 2017-05-31 | 齐鲁工业大学 | A kind of adjustable single-sided film flow controller of precompressed |
| CN108253161A (en) * | 2016-12-29 | 2018-07-06 | 比亚迪股份有限公司 | Expand switch valve |
| CN109139695A (en) * | 2017-06-15 | 2019-01-04 | 重庆西门雷森精密装备制造研究院有限公司 | A kind of filmatic bearing novel thin film throttling set |
-
2020
- 2020-08-31 CN CN202010895242.7A patent/CN111981171B/en active Active
Patent Citations (5)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| GB1017921A (en) * | 1961-05-09 | 1966-01-26 | English Electric Co Ltd | Shaft seal |
| CN102691723A (en) * | 2011-12-17 | 2012-09-26 | 河南科技大学 | Thin film feedback throttling device module, static bearing module and main spindle box module |
| CN108253161A (en) * | 2016-12-29 | 2018-07-06 | 比亚迪股份有限公司 | Expand switch valve |
| CN106763882A (en) * | 2017-03-08 | 2017-05-31 | 齐鲁工业大学 | A kind of adjustable single-sided film flow controller of precompressed |
| CN109139695A (en) * | 2017-06-15 | 2019-01-04 | 重庆西门雷森精密装备制造研究院有限公司 | A kind of filmatic bearing novel thin film throttling set |
Cited By (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN114483787A (en) * | 2021-12-30 | 2022-05-13 | 浙江杭机股份有限公司 | Novel hydrostatic bearing |
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| CN111981171B (en) | 2022-03-08 |
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