CN110939625A - Valve body of unloading overflow valve - Google Patents
Valve body of unloading overflow valve Download PDFInfo
- Publication number
- CN110939625A CN110939625A CN201911251801.4A CN201911251801A CN110939625A CN 110939625 A CN110939625 A CN 110939625A CN 201911251801 A CN201911251801 A CN 201911251801A CN 110939625 A CN110939625 A CN 110939625A
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- China
- Prior art keywords
- hole
- valve core
- unloading
- flow
- valve
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
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Classifications
-
- F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
- F15—FLUID-PRESSURE ACTUATORS; HYDRAULICS OR PNEUMATICS IN GENERAL
- F15B—SYSTEMS ACTING BY MEANS OF FLUIDS IN GENERAL; FLUID-PRESSURE ACTUATORS, e.g. SERVOMOTORS; DETAILS OF FLUID-PRESSURE SYSTEMS, NOT OTHERWISE PROVIDED FOR
- F15B13/00—Details of servomotor systems ; Valves for servomotor systems
- F15B13/02—Fluid distribution or supply devices characterised by their adaptation to the control of servomotors
- F15B13/024—Pressure relief valves
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- F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
- F15—FLUID-PRESSURE ACTUATORS; HYDRAULICS OR PNEUMATICS IN GENERAL
- F15B—SYSTEMS ACTING BY MEANS OF FLUIDS IN GENERAL; FLUID-PRESSURE ACTUATORS, e.g. SERVOMOTORS; DETAILS OF FLUID-PRESSURE SYSTEMS, NOT OTHERWISE PROVIDED FOR
- F15B13/00—Details of servomotor systems ; Valves for servomotor systems
- F15B13/02—Fluid distribution or supply devices characterised by their adaptation to the control of servomotors
- F15B13/029—Counterbalance valves
-
- F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
- F15—FLUID-PRESSURE ACTUATORS; HYDRAULICS OR PNEUMATICS IN GENERAL
- F15B—SYSTEMS ACTING BY MEANS OF FLUIDS IN GENERAL; FLUID-PRESSURE ACTUATORS, e.g. SERVOMOTORS; DETAILS OF FLUID-PRESSURE SYSTEMS, NOT OTHERWISE PROVIDED FOR
- F15B13/00—Details of servomotor systems ; Valves for servomotor systems
- F15B2013/002—Modular valves, i.e. consisting of an assembly of interchangeable components
- F15B2013/004—Cartridge valves
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- Engineering & Computer Science (AREA)
- Physics & Mathematics (AREA)
- Fluid Mechanics (AREA)
- Mechanical Engineering (AREA)
- General Engineering & Computer Science (AREA)
- Safety Valves (AREA)
Abstract
The invention discloses a valve body of an unloading overflow valve, which comprises a valve body, a threaded sleeve and an unloading valve core, wherein a threaded hole, an unloading valve core hole, a communicating hole, a flow through groove and a mounting hole which are communicated with each other are sequentially and coaxially arranged in the valve body from bottom to top; a T port, a P port and an A port are arranged on the circumferential side surface of the valve body; the unloading valve core comprises a valve core body and a valve core cone, wherein a valve core slide rod is arranged on the valve core cone, an annular cutting groove is formed in the circumferential side surface of the valve core slide rod, and a first through flow groove is formed between the annular cutting groove and the inner side wall of the communicating hole; a first flow hole and a second flow hole are arranged in the valve body; an unloading spring is arranged in the threaded hole, a threaded sleeve is arranged at the upper end of the threaded hole, and a first adjusting rod is connected with the threaded sleeve in a threaded manner; a one-way valve core is arranged in the mounting hole, a first spring seat is arranged at an opening at the lower end of the mounting hole, and a one-way spring is arranged in the mounting hole; the unloading overflow valve has the advantages of compact volume, simple processing and low manufacturing cost.
Description
Technical Field
The invention relates to the technical field of hydraulic valves, in particular to a valve body of an unloading overflow valve.
Background
The duplex hydraulic pump is usually used in a special machine tool for machining with the requirements of quick feeding and working feeding, and the duplex pump consists of a high-pressure small-flow hydraulic pump and a low-pressure large-flow hydraulic pump. When the hydraulic pump is used for feeding oil, the two hydraulic pumps supply oil at the same time (the pressure is lower at the moment), when the hydraulic pump is used for feeding oil, the hydraulic pump with high pressure and small flow rate supplies oil (the pressure is higher at the moment), and meanwhile, the large-flow pump is unloaded on an oil circuit system. In the prior art, an unloading valve group is usually adopted to control a duplex hydraulic pump to be switched from quick feed to working feed so as to unload a low-pressure large-flow pump, and the existing unloading valve group is generally integrated on a valve block by an independent one-way valve, an overflow valve and an unloading valve, so that the unloading valve group is large in size and high in cost.
Disclosure of Invention
Technical problem to be solved
The invention aims to overcome the defects in the prior art and provides an unloading overflow valve which is compact in size, simple to machine and low in manufacturing cost.
(II) technical scheme
In order to achieve the purpose, the invention provides the following technical scheme: an unloading overflow valve comprises a valve body, a threaded sleeve and an unloading valve core, wherein a threaded hole, an unloading valve core hole, a communicating hole, a through flow groove and a mounting hole which are communicated with each other are sequentially and coaxially arranged in the valve body from bottom to top; a T port communicated with the unloading valve core hole is arranged at the lower end close to the unloading valve core hole on the circumferential side surface of the valve body, a P port is arranged in the middle of the communicating hole, and an A port communicated with the mounting hole is arranged at the lower end close to the valve body; the unloading valve core comprises a valve core body and a valve core cone, wherein the valve core body is positioned in the unloading valve core hole, the valve core cone is arranged on the valve core body and used for controlling the connection and disconnection of a communication hole and the unloading valve core hole, a valve core slide rod is arranged on the valve core cone and is connected in the communication hole in a sliding mode, an annular cutting groove is formed in the circumferential side face of the valve core slide rod and is close to the valve core cone, and a first through flow groove is formed between the annular cutting groove and the inner; a first flow hole for communicating the P port with the first flow through groove and a second flow hole for communicating the P port with the flow through groove are formed in the valve body; an unloading spring for tightly pressing the valve core cone on the upper end of the communicating hole is arranged in the threaded hole, the threaded sleeve is arranged on the upper end of the threaded hole, and a first adjusting rod for controlling the pre-tightening force of the unloading spring is connected with the internal thread of the threaded sleeve; a one-way valve core used for controlling the communication between the through flow groove and the mounting hole is mounted in the mounting hole, a first spring seat is mounted at an opening at the lower end of the mounting hole, and a one-way spring used for pressing the one-way valve core at the opening at the lower end of the through flow groove is arranged between the first spring seat and the one-way valve core in the mounting hole; a through sliding hole is formed in the one-way valve core along the axial direction of the valve body, a push rod is connected in the sliding hole in a sliding manner, and the upper end of the push rod is connected in the communicating hole in a sliding manner and is connected with the lower end of the valve core sliding rod; a third through hole is formed in the push rod along the axial direction of the push rod; a first groove is axially and downwards formed in the upper end of the valve core body along the valve body, and a fourth flow hole which penetrates through the unloading valve core and is communicated with the third flow hole is axially and downwards formed in the bottom of the first groove along the valve body; an overflow valve core used for controlling the connection and disconnection of the fourth flow hole and the first groove is arranged in the first groove, an overflow spring used for pressing the overflow valve core at an opening at the upper end of the fourth flow hole is arranged in the unloading spring in the threaded hole, and a second adjusting rod used for controlling the pretightening force of the overflow spring is connected with the first adjusting rod in a threaded manner; and a fifth flow hole for communicating the first groove with the T port is formed in the valve core body at the bottom of the first groove.
Through the technical scheme, when the unloading overflow valve works, the P port is connected with the outlet of a low-pressure large-flow pump, the A port is connected with the outlet of a high-pressure small-flow hydraulic pump, and the T port is directly connected with an oil tank; when the motor is started to drive the duplex hydraulic pump to rotate, oil at the outlet of the low-pressure large-flow hydraulic pump acts on the one-way valve core through the P port, the second flow hole and the through-flow groove to overcome the acting force of the one-way spring to push the one-way valve core to move downwards to open the lower end of the flow groove, the oil enters the port A, meanwhile, the oil at the outlet of the high-pressure small-flow pump also enters the port A to realize quick feeding, and the pressure of the port A is lower at the moment; when the quick feeding is finished, the pressure of the port A rises to the pressure set by the unloading spring, the pressure oil of the port A pushes the unloading valve core to overcome the acting force of the unloading spring upwards through the push rod, the valve core cone leaves the upper end of the communicating hole, so that the oil of the port P flows into the port T from the first flow hole and the first through-flow groove to be unloaded, meanwhile, because the pressure difference is generated between the port A and the port P, under the action of the one-way spring and the oil pressure of the port A, the one-way valve core moves upwards to be pressed at the opening at the lower end of the through-flow groove, and the; the duplex hydraulic pump enters a working feeding working condition, only the high-pressure small-flow hydraulic pump supplies oil to the port A, the pressure of the port A can reach higher pressure, the pressure of the port A enables the unloading valve core to be in an opening unloading state all the time, when the pressure of the port A exceeds the pressure set by the overflow spring in the working feeding working condition, oil of the port A pushes the overflow valve core to overcome the acting force of the overflow spring to move upwards through the third flow hole and the fourth flow hole to open the fourth flow hole, and the oil of the port A overflows to the port T through the fifth flow hole, so that the safety protection effect is achieved. The pre-tightening force of the unloading spring can be changed by adjusting the first adjusting rod, so that the unloading pressure is set; the pre-tightening force of the overflow spring can be changed by adjusting the second adjusting rod, so that the overflow pressure is set.
In a further technical scheme, a limiting sleeve sleeved outside the unloading spring and used for limiting the unloading valve core is installed above the unloading valve core in the unloading valve core hole, and a check ring used for preventing the limiting sleeve from being separated from the unloading valve core hole is installed at an opening at the upper end of the unloading valve core hole.
In a further technical scheme, a second spring seat is arranged between the upper end of the overflow spring and the second adjusting rod.
In a further technical scheme, a locking nut is in threaded connection with the first adjusting rod above the threaded sleeve.
(III) advantageous effects
Compared with the prior art, the technical scheme of the invention has the following advantages:
through the design of a plug-in type structure, the unidirectional function, the unloading function and the overflow function are integrated together, the volume is compact, the structure is simple and reasonable, and the manufacturing cost is low.
Drawings
FIG. 1 is a block diagram of the present invention;
FIG. 2 is a structural view of a valve body in the present invention;
FIG. 3 is a structural view of the unloader valve cartridge of the present invention;
FIG. 4 is a hydraulic schematic of the present invention;
fig. 5 is a schematic diagram of the application of the present invention.
Detailed Description
Referring to fig. 1-5, the invention provides an unloading overflow valve, which comprises a valve body 4, a threaded sleeve 9 and an unloading valve core 6, wherein the valve body 4 is internally provided with a threaded hole 401, an unloading valve core hole 402, a communication hole 403, a through flow groove 404 and a mounting hole 405 which are communicated with each other coaxially from bottom to top in sequence; a T port communicated with the unloading valve core hole 402 is arranged at the lower end close to the unloading valve core hole 402 on the circumferential side surface of the valve body 4, a P port is arranged at the middle part of the communicating hole 403, and an A port communicated with the mounting hole 405 is arranged at the lower end close to the valve body 4; the unloading valve core 6 comprises a valve core body 601 positioned in the unloading valve core hole 402 and a valve core cone 602 arranged on the valve core body 601 and used for controlling the on-off of the communicating hole 403 and the unloading valve core hole 402, wherein a valve core slide rod 603 connected in the communicating hole 403 in a sliding manner is arranged on the valve core cone 602, an annular cutting groove 604 is arranged on the circumferential side surface of the valve core slide rod 603 and close to the valve core cone 602, and a first through flow groove 42 is formed between the annular cutting groove 604 and the inner side wall of the communicating hole 403; a first flow hole 4b for communicating the port P with the first through flow groove 42 and a second flow hole 4a for communicating the port P with the through flow groove 404 are formed in the valve body 4; an unloading spring 2b for pressing the valve core cone 602 at the upper end of the communicating hole 403 is installed in the threaded hole 401, the threaded sleeve 9 is installed at the upper end of the threaded hole 401, and a first adjusting rod 8 for controlling the pre-tightening force of the unloading spring 2b is connected with the inner thread of the threaded sleeve 9; a one-way valve core 3 used for controlling the communication between the through flow groove 404 and the mounting hole 405 is mounted in the mounting hole 405, a first spring seat 1 is mounted at an opening at the lower end of the mounting hole 405, and a one-way spring 2a used for pressing the one-way valve core 3 at the opening at the lower end of the through flow groove 404 is arranged between the first spring seat 1 and the one-way valve core 3 in the mounting hole 405; a through sliding hole 301 is formed in the one-way valve core 3 along the axial direction of the valve body 4, a push rod 5 is connected in the sliding hole 301 in a sliding manner, and the upper end of the push rod 5 is connected in a communicating hole 403 in a sliding manner and is connected with the lower end of a valve core sliding rod 603; a third flow hole 51 penetrating through the push rod 5 is formed in the push rod along the axial direction of the push rod; a first groove 605 is formed in the upper end of the valve core body 601 in the axial direction of the valve body 4, and a fourth flow hole 61 which penetrates through the first groove 605 and is communicated with the third flow hole 51 is formed in the unloading valve core 6 in the axial direction of the valve body 4; an overflow valve core 7 used for controlling the connection and disconnection of the fourth flow hole 61 and the first groove 605 is arranged in the first groove 605, an overflow spring 2c used for pressing the overflow valve core 7 at an opening at the upper end of the fourth flow hole 61 is arranged in an unloading spring 2b in the threaded hole 401, and a second adjusting rod 11 used for controlling the pretightening force of the overflow spring 2c is connected with an internal thread of the first adjusting rod 8; a fifth flow hole 606 for communicating the first groove 605 and the T port is provided in the valve body 601 at the bottom of the first groove 605. A stop collar 13 sleeved outside the unloading spring 2b and used for limiting the unloading valve core 6 is installed above the unloading valve core 6 in the unloading valve core hole 402, and a retaining ring 13a used for preventing the stop collar 13 from being separated from the unloading valve core hole 402 is installed at an opening at the upper end of the unloading valve core hole 402. A second spring seat 10 is arranged between the upper end of the overflow spring 2c and the second adjusting rod 11. And a locking nut 12 is in threaded connection with the first adjusting rod 8 above the threaded sleeve 9.
When the unloading overflow valve works, the P port is connected with the outlet of a low-pressure large-flow pump 15, the A port is connected with the outlet of a high-pressure small-flow hydraulic pump 14, and the T port is directly connected with an oil tank 13; when the motor is started to drive the duplex hydraulic pump to rotate, oil at the outlet of the low-pressure large-flow hydraulic pump 15 acts on the one-way valve core 3 through the port P, the second flow hole 4a and the through flow groove 404 to overcome the acting force of the one-way spring 2a to push the one-way valve core 3 to move downwards to open the lower end of the through flow groove 404, the oil enters the port A, meanwhile, the oil at the outlet of the high-pressure small-flow pump 14 also enters the port A, the rapid feeding is realized, and the pressure of the port A is lower at the; when the quick feeding is finished, the pressure of the port A rises to the pressure set by the unloading spring 2b, the pressure oil of the port A pushes the unloading valve core 6 to overcome the acting force of the unloading spring 2b upwards through the push rod 5, the valve core cone 602 leaves the upper end of the communicating hole 403, so that the oil of the port P flows into the port T from the first flow hole 4b and the first through flow groove 42 for unloading, meanwhile, because the pressure difference is generated between the port A and the port P, under the action of the oil pressure of the one-way spring 2a and the port A, the one-way valve core 3 moves upwards to be pressed at the opening at the lower end of the through flow groove 404, and the port P and the; the duplex hydraulic pump enters a working feeding working condition, only the high-pressure small-flow hydraulic pump 14 supplies oil to the port A, the pressure of the port A can reach higher pressure, the pressure of the port A enables the unloading valve core 6 to be always in an opening unloading state, in the working feeding working condition, when the pressure of the port A exceeds the pressure set by the overflow spring 2c, oil of the port A pushes the overflow valve core 7 to move upwards to open the fourth flow hole 61 by overcoming the acting force of the overflow spring 2c through the third flow hole 51 and the fourth flow hole 61, and the oil of the port A overflows to the port T through the first groove 605 and the fifth flow hole 606, so that the safety protection effect is achieved. The pre-tightening force of the unloading spring 2b can be changed by adjusting the first adjusting rod 8, so that the unloading pressure is set; the pretension of the overflow spring 2c can be changed by adjusting the second adjusting lever 11, so that the overflow pressure is set.
The foregoing is only a preferred embodiment of the present invention, and it should be noted that, for those skilled in the art, various modifications and decorations can be made without departing from the technical principle of the present invention, and these modifications and decorations should also be regarded as the protection scope of the present invention.
Claims (2)
1. The valve body of the unloading overflow valve is characterized in that a threaded hole, an unloading valve core hole, a communication hole, a through flow groove and a mounting hole which are communicated with each other are sequentially and coaxially arranged in the valve body from bottom to top; a T port communicated with the unloading valve core hole is arranged at the lower end close to the unloading valve core hole on the circumferential side surface of the valve body, a P port is arranged in the middle of the communicating hole, and an A port communicated with the mounting hole is arranged at the lower end close to the valve body; the unloading valve core comprises a valve core body positioned in an unloading valve core hole and a valve core cone arranged on the valve core body and used for controlling the connection and disconnection of a communication hole and the unloading valve core hole, a valve core slide rod connected in the communication hole in a sliding mode is arranged on the valve core cone, an annular cutting groove is formed in the circumferential side face of the valve core slide rod and close to the valve core cone, and a first through flow groove is formed between the annular cutting groove and the inner side wall of the communication hole; a first flow hole for communicating the P port with the first flow through groove and a second flow hole for communicating the P port with the flow through groove are formed in the valve body; an unloading spring for tightly pressing the valve core cone on the upper end of the communicating hole is arranged in the threaded hole;
a one-way valve core used for controlling the communication between the through flow groove and the mounting hole is mounted in the mounting hole, a first spring seat is mounted at an opening at the lower end of the mounting hole, and a one-way spring used for pressing the one-way valve core at the opening at the lower end of the through flow groove is arranged between the first spring seat and the one-way valve core in the mounting hole; a through sliding hole is formed in the one-way valve core along the axial direction of the valve body, a push rod is connected in the sliding hole in a sliding manner, and the upper end of the push rod is connected in the communicating hole in a sliding manner and is connected with the lower end of the valve core sliding rod; a third through hole is formed in the push rod along the axial direction of the push rod; and a first groove is axially and downwards arranged at the upper end of the valve core body along the valve body.
2. An unloading overflow valve characterized by comprising the valve body of claim 1.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201911251801.4A CN110939625A (en) | 2018-09-27 | 2018-09-27 | Valve body of unloading overflow valve |
Applications Claiming Priority (2)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201911251801.4A CN110939625A (en) | 2018-09-27 | 2018-09-27 | Valve body of unloading overflow valve |
| CN201811133396.1A CN108980133B (en) | 2018-09-27 | 2018-09-27 | Unloading overflow valve |
Related Parent Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN201811133396.1A Division CN108980133B (en) | 2018-09-27 | 2018-09-27 | Unloading overflow valve |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| CN110939625A true CN110939625A (en) | 2020-03-31 |
Family
ID=64543965
Family Applications (3)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN201911250738.2A Withdrawn CN110886735A (en) | 2018-09-27 | 2018-09-27 | Working method of unloading overflow valve |
| CN201911251801.4A Withdrawn CN110939625A (en) | 2018-09-27 | 2018-09-27 | Valve body of unloading overflow valve |
| CN201811133396.1A Active CN108980133B (en) | 2018-09-27 | 2018-09-27 | Unloading overflow valve |
Family Applications Before (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN201911250738.2A Withdrawn CN110886735A (en) | 2018-09-27 | 2018-09-27 | Working method of unloading overflow valve |
Family Applications After (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN201811133396.1A Active CN108980133B (en) | 2018-09-27 | 2018-09-27 | Unloading overflow valve |
Country Status (1)
| Country | Link |
|---|---|
| CN (3) | CN110886735A (en) |
Families Citing this family (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN110657267B (en) * | 2019-11-15 | 2021-02-02 | 临沂市宇顺机械有限公司 | Unloading valve with overflow function |
| CN111594499B (en) * | 2020-05-28 | 2022-04-08 | 宁波华液机器制造有限公司 | Inverse proportion overflow valve |
| CN116906399B (en) * | 2023-07-17 | 2024-04-19 | 杭州励贝电液科技有限公司 | Hydraulic proportional speed regulating valve |
Family Cites Families (5)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| DE19904616A1 (en) * | 1999-02-05 | 2000-08-10 | Mannesmann Rexroth Ag | Control arrangement for at least two hydraulic consumers and pressure differential valve therefor |
| CN1276189C (en) * | 2004-08-04 | 2006-09-20 | 浙江大学 | Pure water unloading overflow valve |
| CN201232209Y (en) * | 2008-07-28 | 2009-05-06 | 福田雷沃国际重工股份有限公司 | Hydraulic double pump unloading system of backhoe loader |
| CN102996556A (en) * | 2012-12-04 | 2013-03-27 | 怀特(中国)驱动产品有限公司 | Direct-acting type hydraulic threaded cartridge balanced valve |
| CN104358902B (en) * | 2014-10-15 | 2016-09-28 | 浙江华益精密机械股份有限公司 | A kind of pressure safety valve |
-
2018
- 2018-09-27 CN CN201911250738.2A patent/CN110886735A/en not_active Withdrawn
- 2018-09-27 CN CN201911251801.4A patent/CN110939625A/en not_active Withdrawn
- 2018-09-27 CN CN201811133396.1A patent/CN108980133B/en active Active
Also Published As
| Publication number | Publication date |
|---|---|
| CN110886735A (en) | 2020-03-17 |
| CN108980133B (en) | 2019-12-20 |
| CN108980133A (en) | 2018-12-11 |
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| PB01 | Publication | ||
| PB01 | Publication | ||
| SE01 | Entry into force of request for substantive examination | ||
| SE01 | Entry into force of request for substantive examination | ||
| WW01 | Invention patent application withdrawn after publication |
Application publication date: 20200331 |
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| WW01 | Invention patent application withdrawn after publication |