CN214118619U - Engineering machinery air conditioner control valve with proportional throttle valve - Google Patents
Engineering machinery air conditioner control valve with proportional throttle valve Download PDFInfo
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- CN214118619U CN214118619U CN202022838589.6U CN202022838589U CN214118619U CN 214118619 U CN214118619 U CN 214118619U CN 202022838589 U CN202022838589 U CN 202022838589U CN 214118619 U CN214118619 U CN 214118619U
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Abstract
The utility model relates to a take engineering machine tool air conditioner control valve of proportion choke valve, include: the temperature control valve comprises a controller, a temperature sensor, a valve body, a proportional throttle valve, an overflow valve and a cover block, wherein the valve body is provided with an oil inlet P1, an oil outlet P2, a first oil return port T1, a second oil return port T2 and a third oil return port T3; the overflow valve includes: the overflow valve comprises a stepped overflow cavity, a valve sleeve, a side hole, a valve core and a cover block, wherein the stepped overflow cavity is arranged in the valve body, the large end of the stepped overflow cavity is communicated with the lower end of the valve body, the valve sleeve is provided with a stepped through hole and is arranged in the large end of the stepped overflow cavity, the side hole is arranged on the side wall of the valve sleeve and is respectively communicated with the bottom of the large end of the stepped through hole, a first oil return port T1 and a second oil return port T2, the valve core is arranged in the large end of the stepped through hole, the lower end of the valve core is provided with a counter bore and an overflow pressure spring positioned in the counter bore, and the cover block presses the lower end of the valve sleeve and the lower end of the overflow pressure spring and is connected with the lower end of the valve body; the inlet of the proportional throttle valve, the small end of the stepped overflow cavity and the small end of the stepped through hole are respectively communicated with an oil inlet P1.
Description
Technical Field
The utility model belongs to the technical field of the engineering machine tool air conditioner and specifically relates to a take engineering machine tool air conditioner control valve of proportion choke valve.
Background
Chinese patent application No.: 201220258994.3, including the engine drive compressor, first two-position three-way switching valve has concatenated on the pipeline between the export of engine drive's compressor and the import of condenser assembly, two-position three-way switching valve of second has concatenated on the pipeline between the import of above-mentioned engine drive's compressor and the export of evaporimeter assembly, the entering of motor compressor, export respectively with the two-position three-way switching valve of above-mentioned first two-position and the two-position three-way switching valve of above-mentioned second intercommunication, the entering of reservoir, export respectively with the export of condenser assembly and the exit intercommunication of evaporimeter.
In the traditional air conditioner of the engineering machinery, a compressor is mostly driven by a hydraulic motor, a hydraulic source of the hydraulic motor adopts a hydraulic system of a main machine of the engineering machinery, and the air conditioner works to realize refrigeration by utilizing surplus power of the main machine while ensuring normal work of a rotary motor of the main machine; the hydraulic motor is provided with an electromagnetic switching valve, an oil inlet of which is communicated with an oil return path of the main machine rotary motor, and the electromagnetic switching valve controls the on-off of the air conditioner; open or close hydraulic motor when host computer rotary motor work, the pressure variation of electromagnetic switch valve switching-over in-process can produce the impact, the existence can arouse host computer rotary motor to appear the shake in the twinkling of an eye, lead to host computer rotary motor work not stable enough, consequently, when designing one kind and opening or close hydraulic motor, the shake in the twinkling of an eye can not appear in host computer rotary motor, the engineering machine air conditioner control valve of area proportion choke valve that host computer rotary motor work remains stable, become the problem of awaiting the opportune moment solution.
SUMMERY OF THE UTILITY MODEL
The utility model aims at overcoming present engineering machine tool's air conditioner and opening or close hydraulic motor when host computer rotary motor works, the pressure variation of solenoid valve switching-over in-process can produce the impact, the existence can arouse host computer rotary motor to appear shaking in the twinkling of an eye, lead to host computer rotary motor work not stable enough, when providing one kind and opening or close hydraulic motor, host computer rotary motor can not appear shaking in the twinkling of an eye, host computer rotary motor work keeps stable engineering machine tool air conditioner control valve of taking the proportion choke valve.
The utility model discloses a concrete technical scheme is:
an engineering machinery air conditioner control valve with a proportional throttle valve comprises: the temperature control valve comprises a controller, a temperature sensor, a valve body, a proportional throttle valve, an overflow valve and a cover block, wherein the valve body is provided with an oil inlet P1, an oil outlet P2, a first oil return port T1, a second oil return port T2 and a third oil return port T3; the overflow valve includes: the overflow valve comprises a stepped overflow cavity, a valve sleeve, a side hole, a valve core and a cover block, wherein the stepped overflow cavity is arranged in the valve body, the large end of the stepped overflow cavity is communicated with the lower end of the valve body, the valve sleeve is provided with a stepped through hole and is arranged in the large end of the stepped overflow cavity, the side hole is arranged on the side wall of the valve sleeve and is respectively communicated with the bottom of the large end of the stepped through hole, a first oil return port T1 and a second oil return port T2, the valve core is arranged in the large end of the stepped through hole, the lower end of the valve core is provided with a counter bore and an overflow pressure spring positioned in the counter bore, and the cover block presses the lower end of the valve sleeve and the lower end of the overflow pressure spring and is connected with the lower end of the valve body; the inlet of the proportional throttle valve, the small end of the stepped overflow cavity and the small end of the stepped through hole are respectively communicated with an oil inlet P1; the temperature sensor and the proportional throttle valve are respectively electrically connected with the controller.
Preferably, the engineering machinery air-conditioning control valve with the proportional throttle valve further comprises a safety valve; the safety valve includes: the safety valve comprises a safety cavity 13 arranged at the left end of a cover block, a pressure regulating seat connected with the cover block and with the right end positioned in the safety cavity 13, a stepped valve hole with the large end arranged at the left end of the pressure regulating seat, a conical valve core with the side wall arranged in the large end of the stepped valve hole and abutting against the left end of the small end of the stepped valve hole, a safety pressure spring with the right end pressing the large end of the conical valve core, a pressure spring seat pressing the left end of the safety pressure spring, a valve cover provided with a screw hole and detachably connected with the left end of the pressure regulating seat, an adjusting screw with one end pressing the left end of the pressure spring seat and screwed with the screw hole, an inlet hole arranged at the side wall of the pressure regulating seat and communicated with the small end of the stepped valve hole, and an outlet hole communicated with the large end of the stepped valve hole; a balance cavity is formed among the large end of the stepped through hole, the valve core and the cover block; the oil outlet P2 and the balance cavity are respectively communicated with the inlet hole; the third oil return port T3 communicates with the outlet hole.
Preferably, the air conditioning control valve with the proportional throttle valve for the construction machinery further comprises: the pressure measuring hole is arranged at the right end of the valve body and is communicated with the inlet hole, and the pressure sensor is arranged at the right end of the inlet hole and is connected with the valve body; the controller is provided with an alarm; the pressure sensor is electrically connected with the controller.
Preferably, a frustum-shaped transition hole is arranged between the large end and the small end of the stepped through hole; the diameter of the small end of the frustum-shaped transition hole is the same as that of the small end of the stepped through hole; the diameter of the big end of the frustum-shaped transition hole is larger than that of the big end of the stepped through hole.
Compared with the prior art, the beneficial effects of the utility model are that: the engineering machinery air conditioner control valve with the proportional throttle valve does not need a traditional electromagnetic switching valve for reversing, a common throttle valve for manually adjusting the flow rate, and the proportional throttle valve for adjusting the flow rate on line in real time by adopting electromagnetic control, and the controller is controlled by the controller to open or close the proportional throttle valve, so that a main machine rotary motor does not shake instantly when the hydraulic motor is opened or closed, and the main machine rotary motor keeps stable in work; when the load of the air conditioner of the engineering machinery changes, the pressure difference between the inlet and the outlet of the proportional throttle valve can be nearly constant due to the pressure compensation effect of the overflow valve connected with the proportional throttle valve in parallel, namely the flow entering through the proportional throttle valve can be kept stable without being influenced by the load change; the safety valve can prevent the system from overloading, when the system is overloaded, the pressure oil pushes the cone valve core to move left to open the safety valve, the pressure at the outlet of the proportional throttle valve is reduced, the valve core of the overflow valve moves downwards, the overflow port is increased, and all the oil from the hydraulic pump overflows back to the oil tank; the adjusting screw rod is rotated, the pre-pressure of the safety pressure spring is adjusted through the pressure spring seat, and the set pressure for opening the safety valve can be adjusted: the alarm is favorable for sending out an alarm when the pressure measured by the overload pressure sensor exceeds a set value; the diameter of the small end of the frustum-shaped transition hole is the same as that of the small end of the stepped through hole; the diameter of the large end of the frustum-shaped transition hole is larger than that of the large end of the stepped through hole, so that the small end of the stepped through hole is communicated with the side hole when the valve core is opened.
Drawings
Fig. 1 is a schematic structural view of the present invention;
FIG. 2 is a view B-B of FIG. 1;
FIG. 3 is a view C-G of FIG. 2;
FIG. 4 is a front view of FIG. 1;
FIG. 5 is a view rotated in the direction H of FIG. 4;
fig. 6 is a hydraulic schematic diagram of the present invention.
In the figure: the pressure regulating valve comprises a controller 1, a temperature sensor 2, a valve body 3, a proportional throttle valve 4, a cover block 5, a stepped overflow cavity 6, a stepped through hole 7, a valve sleeve 8, a side hole 9, a counter bore 10, an overflow pressure spring 11, a valve core 12, a safety cavity 13, a pressure regulating seat 14, a stepped valve hole 15, a conical valve core 16, a safety pressure spring 17, a pressure spring seat 18, a screw hole 19, a valve cover 20, an adjusting screw 21, an inlet hole 22, an outlet hole 23, a balance cavity 24, a pressure measuring hole 25, a pressure sensor 26, an alarm 27, a frustum-shaped transition hole 28, an overflow valve 29, a safety valve 30, an oil inlet P1, an oil outlet P2, a first oil return port T1, a second oil return port T2 and a third oil return port T3.
Detailed Description
The invention will be further described with reference to the drawings.
As shown in figures 1 to 6: an engineering machinery air conditioner control valve with a proportional throttle valve comprises: the temperature control system comprises a controller 1, a temperature sensor 2, a valve body 3 provided with an oil inlet P1, an oil outlet P2, a first oil return port T1, a second oil return port T2 and a third oil return port T3, a proportional throttle valve 4 arranged on the valve body 3 and having an outlet communicated with the oil outlet P2, an overflow valve 29 and a cover block 5; the relief valve 29 includes: the overflow valve comprises a stepped overflow cavity 6, a valve sleeve 8, a side hole 9, a valve core 12 and a cover block 5, wherein the stepped overflow cavity 6 is arranged in a valve body 3, the large end of the stepped overflow cavity 6 is communicated with the lower end of the valve body 3, the valve sleeve 8 is provided with a stepped through hole 7 and is arranged in the large end of the stepped overflow cavity 6, the side hole 9 is arranged on the side wall of the valve sleeve 8 and is respectively communicated with the bottom of the large end of the stepped through hole 7, a first oil return port T1 and a second oil return port T2, the valve core 12 is arranged in the large end of the stepped through hole 7, the lower end of the valve core is provided with a counter bore 10 and an overflow pressure spring 11 positioned in the counter bore 10, and the cover block 5 presses the lower end of the valve sleeve 8 and the lower end of the overflow pressure spring 11 and is in threaded connection with the lower end of the valve body 3; the inlet of the proportional throttle valve 4, the small end of the stepped overflow cavity 6 and the small end of the stepped through hole 7 are respectively communicated with an oil inlet P1; the temperature sensor 2 and the proportional throttle valve 4 are respectively electrically connected with the controller 1.
The engineering machinery air-conditioning control valve with the proportional throttle valve further comprises a safety valve 30; the relief valve 30 includes: the safety valve comprises a safety cavity 13 arranged at the left end of a cover block 5, a pressure regulating seat 14 which is in threaded connection with the cover block 5 and the right end of which is positioned in the safety cavity 13, a stepped valve hole 15 with the large end arranged at the left end of the pressure regulating seat 14, a conical valve core 16 which is arranged at the large end of the stepped valve hole 15 and the side wall of which abuts against the left end of the small end of the stepped valve hole 15, a safety pressure spring 17 with the right end pressing the large end of the conical valve core 16, a pressure spring seat 18 pressing the left end of the safety pressure spring 17, a valve cover 20 which is provided with a screw hole 19 and is in threaded connection with the left end of the pressure regulating seat 14, an adjusting screw 21 with one end pressing the left end of the pressure spring seat 18 and in threaded connection with the screw hole 19, an inlet hole 22 which is arranged at the side wall of the pressure regulating seat 14 and is communicated with the small end of the stepped valve hole 15, and an outlet hole 23 which is communicated with the large end of the stepped valve hole 15; a balance cavity 24 is formed among the large end of the stepped through hole 7, the valve core 12 and the cover block 5; the oil outlet P2 and the balance cavity 24 are respectively communicated with the inlet hole 22; the third oil return port T3 communicates with the outlet hole 23. The inlet holes 22 and the outlet holes 23 are four in number and are evenly distributed along the circumference of the axis of the pressure regulating seat 14.
The engineering machinery air conditioner control valve with the proportional throttle valve further comprises: a pressure measuring hole 25 arranged at the right end of the valve body 3 and communicated with the inlet hole 22, and a pressure sensor 26 arranged at the right end of the inlet hole 22 and screwed with the valve body 3; the controller 1 is provided with an alarm 27; the pressure sensor 26 is electrically connected to the controller 1.
A frustum-shaped transition hole 28 is arranged between the large end and the small end of the stepped through hole 7; the diameter of the small end of the frustum-shaped transition hole 28 is the same as that of the small end of the stepped through hole 7; the diameter of the large end of the frustum-shaped transition hole 28 is larger than that of the large end of the stepped through hole 7.
The control method of the engineering machinery air conditioner control valve with the proportional throttle valve comprises the following steps that (1) pressure oil from a hydraulic system of an engineering machinery main machine is communicated with an oil inlet P1, an oil outlet P2 is communicated with a hydraulic motor for driving a compressor of an air conditioner of the engineering machinery, and a temperature sensor 2 is arranged at the installation position of the air conditioner of the engineering machinery (a cab of the engineering machinery); (2) when the main machine rotary motor works and the hydraulic motor is started, the controller 1 controls and increases the flow of the proportional throttle valve 4 to a set value, when the hydraulic motor is closed, the controller 1 controls and decreases the flow of the proportional throttle valve 4 until the proportional throttle valve 4 is closed, the main machine rotary motor does not shake instantly, and the main machine rotary motor keeps stable in work; (3) according to the set value of the air temperature at the installation position of the air conditioner of the engineering machinery, the controller 1 controls and adjusts the flow of the proportional throttle valve 4, so that the rotating speed of the hydraulic motor is adjusted, and the air temperature at the installation position of the air conditioner of the engineering machinery is kept at the set value; (4) when the temperature sensor 2 detects that the air temperature change at the installation position of the air conditioner of the engineering machinery deviates from a set value, the controller 1 controls and adjusts the flow of the proportional throttle valve 4, so that the rotating speed of the hydraulic motor is adjusted, and the air temperature at the installation position of the air conditioner of the engineering machinery is kept at the set value; (5) the inlet pressure and the outlet pressure of the proportional throttle valve 4 respectively act on the upper end and the lower end of a valve core 12 of the overflow valve 29, the pressure difference between an oil inlet P1 and an oil outlet P2 is the pressure difference between the inlet and the outlet of the proportional throttle valve 4 and is the pressure difference between the upper end and the lower end of the valve core 12 of the overflow valve 29, and the valve core 12 of the overflow valve 29 is in a certain balance position under the action of hydraulic acting force, the spring force of an overflow pressure spring 11 and steady-state hydraulic force; when the load of the air conditioner of the engineering machinery is increased, the outlet pressure of the proportional throttle valve 4 is increased, so that the hydraulic pressure acting on the inlet of the proportional throttle valve 4 is increased, the outlet pressure of a hydraulic pump of a hydraulic system of a host machine of the engineering machinery is increased, the two ends of a valve core 12 of an overflow valve 29 are stressed to restore balance, and the pressure difference between the inlet and the outlet of the proportional throttle valve 4 is basically kept unchanged; similarly, when the load of the air conditioner of the engineering machinery is reduced, the outlet pressure of the proportional throttle valve 4 is reduced, so that the hydraulic pressure acting on the inlet of the proportional throttle valve 4 is reduced, the outlet pressure of a hydraulic pump of a hydraulic system of a host machine of the engineering machinery is reduced, the two ends of the valve core 12 of the overflow valve 29 are stressed and restored to be balanced, and the pressure difference between the inlet and the outlet of the proportional throttle valve 4 is basically kept unchanged; therefore, no matter how the air conditioning load of the engineering machinery changes, the pressure difference between the inlet and the outlet of the proportional throttle valve 4 can be nearly constant due to the pressure compensation effect of the overflow valve 29 connected with the proportional throttle valve 4 in parallel, namely the flow entering through the proportional throttle valve 4 can be kept stable without being influenced by the load change; (6) because the hydraulic pump of the hydraulic system of the engineering machinery host does not work at constant pressure, the outlet pressure of the hydraulic pump changes with the change of the air conditioner load of the engineering machinery, set up the relief valve 30 can prevent the system from overloading, when overloading, the pressure oil promotes the conical valve core 16 to move left and open the relief valve 30, the pressure of outlet port of the proportional throttle valve 4 is reduced, the valve core 12 of the overflow valve 29 moves down, the overflow port increases, all fluid from hydraulic pump overflows and returns to the oil tank; the set pressure for opening the safety valve 30 can be adjusted by rotating the adjusting screw 21 and adjusting the pre-pressure of the safety pressure spring 17 through the pressure spring seat 18.
In addition to the above embodiments, the technical features or technical data of the present invention can be selected and combined again within the scope disclosed in the claims and the specification of the present invention to constitute new embodiments, which can be realized by those skilled in the art without creative efforts, and therefore, the embodiments of the present invention not described in detail should be regarded as specific embodiments of the present invention and within the protection scope of the present invention.
Claims (4)
1. An engineering machinery air conditioner control valve with a proportional throttle valve comprises: the controller, temperature sensor is equipped with the valve body of oil inlet (P1), oil-out (P2), first oil return mouth (T1), third oil return mouth (T3), characterized by, the engineering machine tool air conditioner control valve of area proportion choke valve still include: a proportional throttle valve, an overflow valve and a cover block which are arranged on the valve body and the outlet of which is communicated with the oil outlet (P2); the overflow valve includes: the overflow valve comprises a stepped overflow cavity, a valve sleeve, a side hole, a valve core and a cover block, wherein the stepped overflow cavity is arranged in the valve body, the large end of the stepped overflow cavity is communicated with the lower end of the valve body, the valve sleeve is provided with a stepped through hole and is arranged in the large end of the stepped overflow cavity, the side hole is arranged on the side wall of the valve sleeve and is respectively communicated with the large end of the stepped through hole and a first oil return port (T1), the valve core is arranged in the large end of the stepped through hole, the lower end of; the inlet of the proportional throttle valve, the small end of the stepped overflow cavity and the small end of the stepped through hole are respectively communicated with an oil inlet (P1).
2. The air conditioning control valve for construction machinery with the proportional throttle valve according to claim 1, further comprising a safety valve; the safety valve includes: the safety valve comprises a safety cavity arranged at the left end of a cover block, a pressure regulating seat connected with the cover block and with the right end positioned in the safety cavity, a stepped valve hole with the large end arranged at the left end of the pressure regulating seat, a conical valve core arranged in the large end of the stepped valve hole and abutted against the left end of the small end of the stepped valve hole, a safety pressure spring with the right end pressed against the large end of the conical valve core, a pressure spring seat pressed against the left end of the safety pressure spring, a valve cover provided with a screw hole and detachably connected with the left end of the pressure regulating seat, an adjusting screw with one end pressed against the left end of the pressure spring seat and screwed with the screw hole, an inlet hole arranged at the side wall of the pressure regulating seat and communicated with the small end of the stepped valve hole, and an outlet hole communicated with the large end of the stepped valve hole; a balance cavity is formed among the large end of the stepped through hole, the valve core and the cover block; the oil outlet (P2) and the balance cavity are respectively communicated with the inlet hole; the third oil return port (T3) communicates with the outlet hole.
3. The air conditioning control valve of construction machinery with the proportional throttle valve as set forth in claim 2, further comprising: the pressure measuring hole is arranged at the right end of the valve body and is communicated with the inlet hole, and the pressure sensor is arranged at the right end of the inlet hole and is connected with the valve body; the controller is provided with an alarm.
4. The air-conditioning control valve with the proportional throttle valve for the engineering machinery as claimed in claim 1, 2 or 3, wherein a frustum-shaped transition hole is arranged between the large end and the small end of the stepped through hole; the diameter of the small end of the frustum-shaped transition hole is the same as that of the small end of the stepped through hole; the diameter of the big end of the frustum-shaped transition hole is larger than that of the big end of the stepped through hole.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202022838589.6U CN214118619U (en) | 2020-11-30 | 2020-11-30 | Engineering machinery air conditioner control valve with proportional throttle valve |
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| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202022838589.6U CN214118619U (en) | 2020-11-30 | 2020-11-30 | Engineering machinery air conditioner control valve with proportional throttle valve |
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| CN214118619U true CN214118619U (en) | 2021-09-03 |
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| Application Number | Title | Priority Date | Filing Date |
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| CN202022838589.6U Active CN214118619U (en) | 2020-11-30 | 2020-11-30 | Engineering machinery air conditioner control valve with proportional throttle valve |
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Cited By (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN112483498A (en) * | 2020-11-30 | 2021-03-12 | 杭州精工液压机电制造有限公司 | Engineering machinery air conditioner control valve with proportional throttle valve and control method |
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2020
- 2020-11-30 CN CN202022838589.6U patent/CN214118619U/en active Active
Cited By (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN112483498A (en) * | 2020-11-30 | 2021-03-12 | 杭州精工液压机电制造有限公司 | Engineering machinery air conditioner control valve with proportional throttle valve and control method |
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