CN112431754A - Constant power control valve for plunger pump - Google Patents
Constant power control valve for plunger pump Download PDFInfo
- Publication number
- CN112431754A CN112431754A CN202011601929.1A CN202011601929A CN112431754A CN 112431754 A CN112431754 A CN 112431754A CN 202011601929 A CN202011601929 A CN 202011601929A CN 112431754 A CN112431754 A CN 112431754A
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- Prior art keywords
- valve
- cavity
- spring
- port
- sleeve
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Classifications
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- F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
- F04—POSITIVE - DISPLACEMENT MACHINES FOR LIQUIDS; PUMPS FOR LIQUIDS OR ELASTIC FLUIDS
- F04B—POSITIVE-DISPLACEMENT MACHINES FOR LIQUIDS; PUMPS
- F04B53/00—Component parts, details or accessories not provided for in, or of interest apart from, groups F04B1/00 - F04B23/00 or F04B39/00 - F04B47/00
- F04B53/10—Valves; Arrangement of valves
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- F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
- F04—POSITIVE - DISPLACEMENT MACHINES FOR LIQUIDS; PUMPS FOR LIQUIDS OR ELASTIC FLUIDS
- F04B—POSITIVE-DISPLACEMENT MACHINES FOR LIQUIDS; PUMPS
- F04B1/00—Multi-cylinder machines or pumps characterised by number or arrangement of cylinders
- F04B1/12—Multi-cylinder machines or pumps characterised by number or arrangement of cylinders having cylinder axes coaxial with, or parallel or inclined to, main shaft axis
- F04B1/122—Details or component parts, e.g. valves, sealings or lubrication means
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- F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
- F04—POSITIVE - DISPLACEMENT MACHINES FOR LIQUIDS; PUMPS FOR LIQUIDS OR ELASTIC FLUIDS
- F04B—POSITIVE-DISPLACEMENT MACHINES FOR LIQUIDS; PUMPS
- F04B49/00—Control, e.g. of pump delivery, or pump pressure of, or safety measures for, machines, pumps, or pumping installations, not otherwise provided for, or of interest apart from, groups F04B1/00 - F04B47/00
- F04B49/22—Control, e.g. of pump delivery, or pump pressure of, or safety measures for, machines, pumps, or pumping installations, not otherwise provided for, or of interest apart from, groups F04B1/00 - F04B47/00 by means of valves
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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
- F16K11/00—Multiple-way valves, e.g. mixing valves; Pipe fittings incorporating such valves
- F16K11/10—Multiple-way valves, e.g. mixing valves; Pipe fittings incorporating such valves with two or more closure members not moving as a unit
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- Engineering & Computer Science (AREA)
- General Engineering & Computer Science (AREA)
- Mechanical Engineering (AREA)
- Reciprocating Pumps (AREA)
Abstract
The invention discloses a constant power control valve for a plunger pump, which comprises a valve body, a valve sleeve and a valve core, wherein the valve sleeve is arranged on the valve body; the valve sleeve is arranged in the valve cavity of the valve body in a sliding manner, the valve core is arranged in the sleeve cavity of the valve sleeve in a sliding manner, and the valve sleeve is provided with a P port and a B port; the valve core is provided with a small annular boss and a large annular boss which are used for pushing the valve core to move forwards by utilizing the pressure difference formed by the area difference of the pressure oil at the port P when the pressure oil reaches a set value, an M cavity communicated with the port P is formed between the small annular boss and the large annular boss, and the M cavity is communicated with the port P and the port B when the valve core moves forwards so that the pressure oil at the port P flows back to a variable piston cavity of the plunger pump; the valve body is provided with a feedback rod which drives the valve sleeve to move forward to control the size of an opening between the cavity M and the opening B when the variable piston pushes the swash plate to change the swing angle. The invention has compact structure, simple manufacture, small volume and quick response, can control the input and output power of the plunger pump to be approximately constant so as to meet the requirements of a hydraulic system of engineering machinery and achieve the energy-saving effect at the same time.
Description
Technical Field
The invention relates to the technical field of hydraulic control, in particular to a control valve for controlling the output power of a pump, and specifically relates to a constant power control valve for a plunger pump.
Background
The hydraulic source of the hydraulic system is mainly provided by a hydraulic pump, and the hydraulic pump can be divided into a quantitative hydraulic pump and a variable hydraulic pump according to a variable form. The variable hydraulic pump can control the flow rate through the constant power control valve, and the discharge capacity of the pump is adjusted according to the working pressure of a load, so that the power is at a constant driving rotating speed, and the energy-saving effect of a hydraulic system is achieved. The constant power control valve in the prior art is generally complex in structure, large in size, slow in response speed and slow in control.
Disclosure of Invention
The present invention provides a constant power control valve for a plunger pump, which has a compact structure, is simple to manufacture, has a small volume, a fast response, and a small pressure hysteresis loop, and is used for solving the technical problems of the prior art.
The technical scheme adopted by the invention for solving the technical problems is as follows:
a constant power control valve for a plunger pump comprises a valve body, a valve sleeve and a valve core; the valve sleeve is arranged in the valve cavity of the valve body in a sliding manner, the valve core is arranged in the sleeve cavity of the valve sleeve in a sliding manner, and the valve sleeve is provided with a P port for communicating an oil outlet of the plunger pump and a B port for communicating a variable piston cavity of the plunger pump; the valve core is provided with a small annular boss and a large annular boss which are used for pushing the valve core to move forwards by utilizing the pressure difference formed by the area difference of the pressure oil at the port P when the pressure oil reaches a set value, an M cavity communicated with the port P is formed between the small annular boss and the large annular boss, and the M cavity is communicated with the port P and the port B when the valve core moves forwards so that the pressure oil at the port P flows back to a variable piston cavity of the plunger pump; the valve body is provided with a feedback rod, one end of the feedback rod is used for being connected with the other end of a swash plate of the plunger pump and is used for being connected with a valve sleeve, and the feedback rod drives the valve sleeve to move forwards to control the size of an opening between the M cavity and the B port when the variable piston pushes the swash plate to change a swing angle.
In order to optimize the technical scheme, the specific measures adopted further comprise:
the rear end of the valve cavity is spirally provided with a rear valve plug, the front section of the valve cavity is expanded to form a spring cavity, a spring assembly used for setting the working pressure of the valve core is arranged in the spring cavity, the spring assembly comprises a large spring and a small spring sleeved in the large spring, the front end of the valve core is connected with a rear spring seat in a propping mode, and the rear end of the large spring and the rear end of the small spring are connected to the front end face of the rear spring seat in a propping mode.
An adjusting screw sleeve for adjusting the pre-tightening pressure of the large spring is spirally mounted at the cavity opening of the spring cavity, and a first nut for preventing the adjusting screw sleeve from loosening is spirally mounted on the adjusting screw sleeve; a spring seat cavity is formed in the adjusting screw sleeve, a front spring seat matched with the front end of the small spring in an abutting mode is arranged in the spring seat cavity, and the front end of the large spring is abutted to the annular surface of the cavity opening of the spring seat cavity.
The adjusting screw sleeve is provided with an adjusting screw hole communicated with the spring seat cavity, an adjusting screw rod used for adjusting the pre-tightening pressure of the small spring is spirally arranged in the adjusting screw hole, the adjusting screw rod is abutted with the front spring seat, and a second nut used for preventing the adjusting screw rod from loosening is spirally arranged on the adjusting screw rod.
A first sealing ring is arranged between the rear port of the valve cavity and the rear valve plug in a pressing mode, a second sealing ring which is in sealing fit with the adjusting screw sleeve is arranged in the spring cavity in a pressing mode, and a third sealing ring is arranged between the adjusting screw sleeve and the front spring seat in a pressing mode.
The spring cavity is provided with a T port for discharging oil leaked into the spring cavity out of the valve cavity, and the T port is communicated with an oil return cavity of the plunger pump.
The valve core is formed with a guide oil duct for guiding oil leaked into the rear end of the valve sleeve into the spring cavity, and the guide oil duct comprises an axial oil duct axially processed from the rear end surface of the valve core and a radial oil duct for communicating the axial oil duct with the spring cavity.
The feedback rod is connected with the swash plate in a sliding block mode, and the feedback rod is provided with an opening sliding groove used for clamping the sliding block.
Compared with the prior art, the valve sleeve is arranged in the valve cavity of the valve body and can slide along the valve cavity, the valve core is arranged in the sleeve cavity of the valve sleeve and can slide along the sleeve cavity, the small annular boss and the large annular boss are formed on the valve core, the M cavity communicated with the P port is formed between the small annular boss and the large annular boss, and the difference of the area of the small annular boss and the area of the large annular boss is formed because the diameter of the small annular boss is smaller than that of the large annular boss. The pressure oil entering the M cavity has different pressure differences caused by the area difference between the small annular boss and the large annular boss, so that the valve core can move forwards under the action of the pressure differences, and the port P and the port B of the channel valve are communicated; the valve body is provided with a feedback rod which drives the valve sleeve to move forward to control the size of an opening between the cavity M and the opening B when the variable piston pushes the swash plate to change the swing angle.
The invention has compact structure, simple manufacture, small volume and quick response, can control the input and output power of the plunger pump to be approximately constant so as to meet the requirements of a hydraulic system of engineering machinery and achieve the energy-saving effect at the same time.
Drawings
FIG. 1 is a schematic structural view of the present invention;
fig. 2 is a sectional structural view of the valve cartridge of fig. 1.
Detailed Description
Embodiments of the present invention are described in further detail below with reference to the accompanying drawings.
Fig. 1 to 2 are schematic structural views of the present invention.
Wherein the reference numerals are: the valve comprises a first sealing ring F1, a second sealing ring F2, a third sealing ring F3, a valve body 1, a spring cavity 1a, a valve sleeve 2, a valve core 3, an axial oil passage 3a, a radial oil passage 3b, a small annular boss 31, a large annular boss 32, a feedback rod 4, an opening sliding groove 4a, a rear valve plug 5, a large spring 61, a small spring 62, a front spring seat 71, a rear spring seat 72, an adjusting wire sleeve 8, a first nut 81, an adjusting screw rod 9 and a second nut 91.
As shown in fig. 1 to 2, the present invention discloses a constant power control valve for a plunger pump, which includes a valve body 1, a valve housing 2, and a valve core 3. The valve body 1 is axially formed with a valve cavity in a penetrating manner, the valve sleeve 2 is axially formed with a sleeve cavity in a penetrating manner, the valve sleeve 2 is arranged in the valve cavity of the valve body 1 in a sliding manner, and the valve core 3 is arranged in the sleeve cavity of the valve sleeve 2 in a sliding manner. A P port and a B port which are communicated with a sleeve cavity in the radial direction are formed in a valve sleeve 2, the P port is used for being connected with an oil outlet of a plunger pump, and the B port is used for being connected with a variable piston cavity of the plunger pump. A small annular boss 31 is formed at the rear end of the valve core 3, a large annular boss 32 is formed at the middle position of the valve core 3, and the diameter of the large annular boss 32 is larger than that of the small annular boss 31. An M cavity communicated with the P port is formed between the small annular boss 31 and the large annular boss 32, so that hydraulic oil of the oil outlet of the plunger pump can enter the M cavity, and the small annular boss 31 and the large annular boss 32 of the valve core 3 have different diameters to form an area difference on annular surfaces of the small annular boss and the large annular boss, so that the valve core 3 can slide forwards along the sleeve cavity of the valve sleeve 2 under the action of the hydraulic oil entering the M cavity when the pressure difference caused by the area difference reaches a set value. The M cavity has a certain length, and the M cavity can communicate the P port with the B port when the valve core 3 moves forwards, so that hydraulic oil at the oil outlet of the plunger pump can flow back to the variable piston cavity of the plunger pump through the P port and the M cavity, and the variable piston can push the swash plate under the action of the entering hydraulic oil so as to change the swing angle of the swash plate to realize the change of the output flow of the pump. The valve body 1 is provided with a feedback rod for feeding back the swing angle change of the swash plate, one end of the feedback rod penetrates through the valve body 1 and is connected with the swash plate of the plunger pump, and the other end of the feedback rod is connected with the valve sleeve 3. When the variable piston pushes the swash plate to change the swing angle of the swash plate, the swash plate can drive the valve sleeve 3 to move forwards through the feedback rod 4, the product of the pump outlet flow and the outlet pressure is ensured to be approximately constant by controlling the opening size between the cavity M and the port B, and the constant power control of the plunger pump is realized.
In the embodiment, as can be seen from fig. 1, a rear valve plug 5 is spirally mounted at the rear port of the valve cavity, and a first sealing ring F1 is further press-fitted between the rear port of the valve cavity and the rear valve plug 5 in order to prevent oil leakage at the rear port of the valve cavity. The front section of the valve cavity is formed with a spring cavity 1a by expanding, a spring assembly for setting the working pressure of the valve core 3 is arranged in the spring cavity 1a, and the pressure difference reaches the set value, namely the pressure difference needs to overcome the spring force of the spring assembly. The spring assembly includes a large spring 61 and a small spring 62 nested within the large spring 61. The front end of the valve core 3 is abutted with a rear spring seat 72, and the rear end of the large spring 61 and the rear end of the small spring 62 are both abutted on the front end surface of the rear spring seat 72. Under the action of spring force in an original state, the front end face of the rear valve plug 5 is in limit abutting fit with the rear end face of the valve core 3.
In the embodiment, an adjusting screw sleeve 8 is spirally mounted at the orifice of a spring cavity 1a of the valve body 1, the adjusting screw sleeve 8 is used for adjusting the pre-tightening pressure of the large spring 61, and in order to prevent the adjusting accuracy affected by the adjusting screw sleeve 8 after the adjustment is completed, a first nut 81 is spirally mounted on the adjusting screw sleeve 8. The first nut 81 abuts against the front end of the valve body 1, and can lock and fix the adjusting screw sleeve 8 at an adjusting position. The adjusting screw sleeve 8 is also provided with a spring seat cavity, a front spring seat 71 is slidably arranged in the spring seat cavity, the rear end surface of the front spring seat 71 is in abutting fit with the front end of the small spring 62, and the front end of the large spring 61 abuts against the annular surface of the opening of the spring seat cavity.
In the embodiment, the adjusting screw sleeve 8 of the invention is formed with an adjusting screw hole communicated with the spring seat cavity, the adjusting screw 9 for adjusting the pre-tightening pressure of the small spring 62 is spirally mounted in the adjusting screw hole, the adjusting screw 9 is abutted with the front end surface of the front spring seat 71, and similarly, in order to prevent the adjusting screw 9 from loosening after adjustment is completed, the adjusting screw 9 is spirally mounted with a second nut 91.
In the embodiment, as can be seen from fig. 1 of the present invention, a second sealing ring F2 is press-fitted into the spring chamber 1a of the present invention to be in sealing engagement with the adjusting screw bushing 8, and a third sealing ring F3 is press-fitted between the adjusting screw bushing 8 and the front spring seat 71.
A T port is formed in a spring cavity 1a of the plunger pump and is communicated with an oil return cavity of the plunger pump and used for discharging oil leaked into the spring cavity 1a out of a valve cavity. As shown in fig. 2, the valve core 3 of the present invention is formed with a guide oil passage for guiding oil leaked into the rear end of the valve housing 2 into the spring chamber 1a, and the guide oil passage includes an axial oil passage 3a axially machined from the rear end surface of the valve core 3 and a radial oil passage 3b for communicating the axial oil passage 3a with the spring chamber 1 a. If there is leaked oil in the spring chamber 1a or the valve chamber at the rear end of the valve housing 2 and the leaked oil cannot be discharged, the oil will form oil pressure when the valve core moves, thereby affecting the accuracy of the valve action
As shown in FIG. 1, a feedback rod 4 of the present invention is connected to a swash plate in a slider type, and the feedback rod 4 is provided with an open slide groove 4a for engaging with the slider.
The working principle of the invention is as follows:
as shown in figure 1, when the valve is used on a plunger pump, a port P, a port B and a port T are respectively communicated with an oil outlet, a variable piston cavity and an oil return cavity of the plunger pump, and a feedback rod 4 is connected with a swash plate of the plunger pump in a sliding block mode. When hydraulic oil of the pump enters the M cavity through the P port, the hydraulic oil acts on the annular end face of the small annular boss 31 of the valve core 3 and the annular end face of the large annular boss 32, because the outer circle sizes of the small annular boss 31 and the large annular boss of the valve core 3 are different to form an area difference, when the hydraulic oil of the oil outlet of the pump reaches a set value, the valve core 3 overcomes the spring force of the large spring 61 to move rightwards (namely forwards) under the acting force generated by the area difference, the M cavity is communicated with the B cavity, the hydraulic oil flows to the variable piston cavity of the plunger pump through the B port, the variable piston drives the swash plate to change the swing angle under the action of the hydraulic oil to realize the change of the output flow of the pump, the swash plate drives the valve sleeve 2 to move rightwards through the feedback rod 4 while swinging, the opening size between the M cavity and the B port is controlled, thereby ensuring that the product of the flow, when the pressure of the oil outlet of the pump rises to a certain value, the small spring 62 also generates acting force, a second variable characteristic curve is formed by the same principle, and the two curves are combined to form an approximate constant power curve. The control mode can ensure that the input power of the pump is approximately constant under the constant rotating speed, so that the energy of a motor or an engine for driving the pump can be better utilized, and the pump is not blocked.
While the preferred embodiments of the present invention have been illustrated, various changes and modifications may be made by one skilled in the art without departing from the scope of the invention.
Claims (8)
1. A constant power control valve for a plunger pump comprises a valve body (1), a valve sleeve (2) and a valve core (3); the method is characterized in that: the valve sleeve (2) is slidably arranged in the valve cavity of the valve body (1), the valve core (3) is slidably arranged in the sleeve cavity of the valve sleeve (2), and the valve sleeve (2) is provided with a P port for communicating an oil outlet of the plunger pump and a B port for communicating a variable piston cavity of the plunger pump; the valve core (3) is provided with a small annular boss (31) and a large annular boss (32) which are used for pushing the valve core (3) to move forwards by utilizing the pressure difference formed by the area difference of the pressure oil at the port P when the pressure oil reaches a set value, an M cavity communicated with the port P is formed between the small annular boss (31) and the large annular boss (32), and the M cavity is communicated with the port P and the port B when the valve core (3) moves forwards so that the pressure oil at the port P flows back to a variable piston cavity of the plunger pump; the valve body (1) is provided with a feedback rod (4) of which one end is connected with the other end of a swash plate of the plunger pump and is connected with the valve sleeve (3), and the feedback rod (4) drives the valve sleeve (3) to move forwards to control the size of an opening between the cavity M and the opening B when the variable piston pushes the swash plate to change a swing angle.
2. The constant power control valve for a plunger pump according to claim 1, wherein: the rear valve plug (5) is spirally mounted at the rear port of the valve cavity, a spring cavity (1a) is formed in the front section of the valve cavity in an expanding mode, a spring assembly used for setting the working pressure of the valve core is mounted in the spring cavity (1a), the spring assembly comprises a large spring (61) and a small spring (62) sleeved in the large spring (61), a rear spring seat (72) is connected to the front end of the valve core (3) in an abutting mode, and the rear end of the large spring (61) and the rear end of the small spring (62) are connected to the front end face of the rear spring seat (72) in an abutting mode.
3. A constant power control valve for a plunger pump according to claim 2, wherein: an adjusting screw sleeve (8) used for adjusting the pre-tightening pressure of the large spring (61) is spirally mounted at the cavity opening of the spring cavity (1a), and a first nut (81) used for preventing the adjusting screw sleeve (8) from loosening is spirally mounted on the adjusting screw sleeve (8); a spring seat cavity is formed in the adjusting screw sleeve (8), a front spring seat (71) in abutting fit with the front end of the small spring (62) is arranged in the spring seat cavity, and the front end of the large spring (61) abuts against the annular surface of the cavity opening of the spring seat cavity.
4. A constant power control valve for a plunger pump according to claim 3, wherein: the adjusting screw rod hole that the adjusting screw cover (8) shaping had intercommunication spring seat chamber, the spiral is installed in this adjusting screw rod hole and is used for adjusting little spring (62) pretension pressure adjusting screw rod (9), adjusting screw rod (9) with preceding spring holder (71) looks butt joint to spiral installation is used for preventing adjusting screw rod (9) not hard up second nut (91) on adjusting screw rod (9).
5. The constant power control valve for a plunger pump according to claim 4, wherein: the back port of valve chamber and back valve block (5) are pressed from both sides and are equipped with first sealing washer (F1), spring chamber (1a) middling pressure be equipped with adjust wire sleeve (8) sealed cooperation second sealing washer (F2), adjust wire sleeve (8) and preceding spring holder (71) between the pressure be equipped with third sealing washer (F3).
6. The constant power control valve for a plunger pump according to claim 5, wherein: and a T port for discharging oil leaked into the spring cavity (1a) out of the valve cavity is formed in the spring cavity (1a), and the T port is communicated with an oil return cavity of the plunger pump.
7. The constant power control valve for a plunger pump according to claim 6, wherein: the oil leakage prevention valve is characterized in that a guide oil channel for guiding oil leaked into the rear end of the valve sleeve (2) into the spring cavity (1a) is formed in the valve core (3), and the guide oil channel comprises an axial oil channel (3a) and a radial oil channel (3b), wherein the axial oil channel (3a) is axially machined from the rear end face of the valve core (3), and the radial oil channel (3b) is used for communicating the axial oil channel (3a) with the spring cavity (1 a).
8. The constant power control valve for a plunger pump according to claim 7, wherein: the feedback rod (4) is connected with the swash plate in a sliding block mode, and the feedback rod (4) is provided with an opening sliding groove (4a) used for clamping the sliding block.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202011601929.1A CN112431754A (en) | 2020-12-30 | 2020-12-30 | Constant power control valve for plunger pump |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202011601929.1A CN112431754A (en) | 2020-12-30 | 2020-12-30 | Constant power control valve for plunger pump |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| CN112431754A true CN112431754A (en) | 2021-03-02 |
Family
ID=74697055
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN202011601929.1A Pending CN112431754A (en) | 2020-12-30 | 2020-12-30 | Constant power control valve for plunger pump |
Country Status (1)
| Country | Link |
|---|---|
| CN (1) | CN112431754A (en) |
Cited By (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN115507186A (en) * | 2022-11-01 | 2022-12-23 | 中航力源液压股份有限公司 | Constant-power electric pump device for airplane emergency brake system and application method |
-
2020
- 2020-12-30 CN CN202011601929.1A patent/CN112431754A/en active Pending
Cited By (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN115507186A (en) * | 2022-11-01 | 2022-12-23 | 中航力源液压股份有限公司 | Constant-power electric pump device for airplane emergency brake system and application method |
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