CN220706560U - Empty stroke eliminating structure of pilot type electromagnetic valve - Google Patents

Abstract

The utility model discloses an idle stroke eliminating structure of a pilot electromagnetic valve, which comprises a valve body and a piston block, wherein the valve body comprises a large valve seat and a small valve seat, a liquid inlet which transversely extends rightwards is formed in the middle of the left end face of the large valve seat, a liquid outlet which transversely extends leftwards is formed in the middle of the right end face of the large valve seat, a convex connecting part which extends upwards is formed in the middle of the top face of the large valve seat, a first stepped hole which extends downwards is formed in the middle of the top face of the convex connecting part, and the lower part of the small valve seat is arranged in the upper hole section of the first stepped hole; the buffer spring and the upper sealing block are guided by the guide sleeve in a spaced mode, normal use of the buffer spring is guaranteed, stable operation of the upper sealing block is guaranteed, and the buffer spring does not directly act on the piston block, so that normal operation of the piston block is guaranteed.

Description

Empty stroke eliminating structure of pilot type electromagnetic valve

Technical field:

the utility model relates to the technical field of electromagnetic valve components, in particular to a structure for eliminating idle stroke of a pilot-operated electromagnetic valve.

The background technology is as follows:

the electromagnetic valve is mainly applied to various control systems, such as refrigeration or heating systems, and realizes a certain flow path closing or conducting function in the system by switching on and off according to the system requirement. The pilot-operated solenoid valve adopts a two-stage opening mode: the pilot valve on the piston is opened firstly, the pressure difference between the upper and lower parts of the piston is changed, and the piston is opened by the pressure difference force. The pilot electromagnetic valve realizes that the small power drives the large valve port, and ensures the circulation capacity of the system. For convenience of installation, the inlet and outlet interfaces are required to be in a sub-shape configuration, and the flow resistance is required to be as small as possible.

The prior pilot electromagnetic valve, such as a pilot electromagnetic valve disclosed in Chinese patent publication No. CN 203571179U: a protrusion is provided around an opening of a guide passage of the piston valve, the guide passage opening from a pilot port (1 a) to a secondary side joint. The influence of the flow of the fluid from the primary side is suppressed by the projection. The ratio A of the length of the protrusion to the amount of rise of the piston valve, and the ratio B of the area of the surface perpendicular to the axis of the protrusion, that is, the area of the protrusion to the aperture area of the main valve port, satisfy 0.4.ltoreq.A.ltoreq.1.0 and 0<B.ltoreq.0.08. In this pilot solenoid valve, the pressure in the piston back space is easily released to the secondary side, so that the stable operation of the piston valve is realized, and the drop in the fully open flow rate (fully open Cv value) is prevented.

The sealing block (hereafter called sealing block) on the upper part of the protrusion is connected with the pilot valve body in a riveting way, the pilot valve body can be axially movably arranged on the plunger, a spring is arranged between the pilot valve body and the piston part, and under the condition that the plunger is fully opened, the spring can eliminate idle stroke between the pilot valve body and the plunger. The idle stroke as described above is also important for reliable plunger action, and the effect of the idle stroke has two points: 1. because the movable assembly between the plunger and the pilot valve body is adopted, the sealing block is also in movable assembly relative to the plunger, when the plunger and the piston block have position errors, the sealing block can correct the errors, and the reliable sealing between the sealing block and the pilot port is ensured under the condition of power failure; 2. the existence of idle stroke makes the plunger obtain a larger initial speed under a lower load (no load generated by air pressure at the moment), and greatly improves the action capability of the plunger under low voltage and high load. However, the idle stroke is ineffective to the stroke of the sealing block, and the sealing block cannot move during the idle stroke. Under the conditions of full opening of the plunger and full opening of the piston part, as the pressure difference born by the sealing block is smaller, the spring force can eliminate idle stroke, so that the pressure in the back space of the piston is easy to release to the secondary side, the stable action of the piston valve is realized, and the drop of the full opening flow (full opening Cv value) is prevented.

The problem of decline of full open flow (full open Cv value) has been solved to above-mentioned scheme fine, but this spring force acts on between sealing block (or guide's valve body) and piston portion, and spring force has produced great back pressure to piston portion, can lead to piston portion to receive too big and damage, influences its life.

The utility model comprises the following steps:

the utility model aims to overcome the defects of the prior art and provides an idle stroke eliminating structure of a pilot type electromagnetic valve, which is used for guiding a buffer spring and an upper sealing block through a guide sleeve in a separated way, ensuring the normal use of the buffer spring and the stable operation of the upper sealing block, and ensuring the normal operation of the piston block because the buffer spring does not directly act on the piston block.

The scheme for solving the technical problems is as follows:

the pilot electromagnetic valve comprises a valve body and a piston block, wherein the valve body comprises a large valve seat and a small valve seat, a liquid inlet which transversely extends rightward is formed in the middle of the left end face of the large valve seat, a liquid outlet which transversely extends leftward is formed in the middle of the right end face of the large valve seat, a convex connecting part which extends upward is formed in the middle of the top surface of the large valve seat, a first stepped hole which extends downward is formed in the middle of the top surface of the convex connecting part, and the lower part of the small valve seat is arranged in the upper hole section of the first stepped hole;

the middle part of the small valve seat is provided with a vertically extending piston guide stepped through hole, a piston block is inserted and sleeved in the middle part of the piston guide stepped through hole, a sleeve is clamped at the upper part of the piston guide stepped through hole, a movable iron core is inserted and sleeved in the lower part of the sleeve, the middle part of the bottom surface of the movable iron core is provided with a downwardly extending protruding column, and the bottom of the extending protruding column extends out of the middle through hole of the bottom plate of the sleeve; the bottom surface middle part shaping that extends protruding post has the buffering shrinkage pool that upwards extends, install the uide bushing in the buffering shrinkage pool, upper portion sealing block plug bush is in the uide bushing, the bottom of uide bushing is stretched out to the bottom of upper portion sealing block and is pressed on the middle part top surface of piston block, the buffering spring plug bush is on the uide bushing and in the buffering shrinkage pool, the top shaping of upper portion sealing block has the external diameter to be greater than the upper limit portion of upper portion sealing block, upper limit portion is in the top of uide bushing, buffer spring's top is exerted on the bottom surface of upper limit portion, buffer spring's bottom is exerted on the lower part of uide bushing.

The lower part inside wall of buffering shrinkage pool is last to be formed with radial extension ring channel, and the uide bushing plug bush is in the buffering shrinkage pool, and the limit portion plug bush of the radial limit of shaping on the bottom lateral wall of uide bushing is in radial extension ring channel, and radial limit lateral wall card is put on radial extension ring channel's inside wall, and radial extension ring channel's bottom curb plate downwardly extending, its bottom is less than radial limit bottom surface.

And a buffer spring is inserted on the outer side wall of the guide sleeve, and the bottom end of the buffer spring is applied to the top surface of the radial edge of the guide sleeve.

The utility model has the outstanding effects that:

the buffer spring and the upper sealing block are guided by the guide sleeve in a spaced mode, normal use of the buffer spring is guaranteed, stable operation of the upper sealing block is guaranteed, and the buffer spring does not directly act on the piston block, so that normal operation of the piston block is guaranteed.

Description of the drawings:

FIG. 1 is a partial schematic view of the upper seal block of the present utility model in an intermediate position;

FIG. 2 is an enlarged view of a portion of FIG. 1;

FIG. 3 is a schematic view of the partial construction of the large and small valve bodies of the present utility model;

FIG. 4 is a schematic view of a partial structure of a piston block;

FIG. 5 is a partial schematic view of the upper seal block in a fully open state;

FIG. 6 is a partial schematic view of the upper seal block in a fully closed condition;

fig. 7 is a partial enlarged view of fig. 6.

The specific embodiment is as follows:

1-7, an idle stroke eliminating structure of a pilot type electromagnetic valve comprises a valve body and a piston block 30, wherein the valve body comprises a large valve seat 10 and a small valve seat 20, a liquid inlet 11 transversely extending rightward is formed in the middle of the left end face of the large valve seat 10, a liquid outlet 12 transversely extending leftward is formed in the middle of the right end face of the large valve seat 10, a convex connecting part 13 extending upward is formed in the middle of the top face of the large valve seat 10, a first stepped hole 14 extending downward is formed in the middle of the top face of the convex connecting part 13, an annular protruding part 15 extending upward is formed in the middle of the bottom face of the first stepped hole 14, a valve port 151 is formed in the middle of the annular protruding part 15, the bottom end of the valve port 151 vertically extends downward and is communicated with the liquid outlet 12, a downward extending communication hole 141 is formed in the bottom face of the left part of the first stepped hole 14, and the communication hole 141 is communicated with the liquid inlet 11;

the upper hole Duan Da of the first stepped hole 14 is formed in the lower hole section, the lower part of the small valve seat 20 is inserted and sleeved in the upper hole section of the first stepped hole 14, the outer side wall of the lower part of the small valve seat 20 is welded and fixed on the inner side wall of the upper hole section of the first stepped hole 14 in a brazing manner, and the edge part of the bottom end face of the small valve seat 20 is pressed against the bottom end face of the upper hole section of the first stepped hole 14; because the small valve body 20 and the large valve body 10 are welded and fixed, the small valve body 20 and the large valve body 10 cannot generate loosening problems, and the inside of the small valve body is machined after the small valve body and the large valve body are fixed, for example, the inner wall of the vertically extending piston guide stepped through hole 21 in the middle of the small valve seat 20, the top surface of the annular protruding portion 15 and the like are machined, the small valve seat can be clamped once and continuously machined, and therefore the size and the position error of finish machining can be guaranteed.

Further, a vertically extending piston guiding stepped through hole 21 is formed in the middle of the small valve seat 20, a piston block 30 is inserted into the piston guiding stepped through hole 21, a vertical valve hole 31 is formed in the middle of the piston block 30, the vertical valve hole 31 is communicated with a valve port 151, an upper annular diversion trench 32 is formed at the edge of the top surface of the piston block 30, a vertical diversion trench 33 is formed at the bottom surface of the upper annular diversion trench 32, a radial flow through hole 34 is formed at the bottom side wall of the vertical diversion trench 33, the outer end of the radial flow through hole 34 extends out of the outer side wall of the piston block 30 and is communicated with a diversion annular groove 22 formed on the inner side wall of the bottom end of the piston guiding stepped through hole 21, and the diversion annular groove 22 is communicated with the first stepped hole 14. The upper annular guide groove 32, the vertical guide hole 33 and the radial flow hole 34 on the piston block 30 form a balance channel, so that liquid above the piston block 30 can flow out conveniently, pressure relief is facilitated, and a gap between the outer side wall of the piston block 30 and the inner side wall of the lower small-diameter hole section of the piston guide stepped through hole 21 can be greatly reduced, so that stable lifting operation of the piston block 30 can be ensured. The flow guiding annular groove 22 increases the liquid flowing space at the first stepped hole 14, so that the liquid between the liquid inlet 11 and the liquid outlet 12 flows smoothly, and the liquid flow resistance is reduced.

Further, the outer side wall of the piston block 30 is stepped, and the outer diameter of the upper section is larger than that of the lower section; the piston guiding stepped through hole 21 comprises an upper large-diameter hole section, a middle transition hole section and a lower small-diameter hole section, wherein the inner diameter of the upper large-diameter hole section is from large to small, the lower small-diameter hole section is communicated with the flow guiding annular groove 22, and the outer side wall of the upper section of the piston block 30 is close to or clung to the inner side wall of the lower small-diameter hole section of the piston guiding stepped through hole 21.

Further, the middle part of the bottom surface of the piston block 30 is formed with a lower groove 35, the vertical valve hole 31 is communicated with the lower groove 35, the lower sealing block 40 is clamped in the lower groove 35, and during processing, the bottom end edge of the piston block 30 can be bent inwards, and the bottom end edge of the lower sealing block 40 is pressed against to further realize fixation, and the structure is not shown in the drawing.

The outer sidewall of the lower sealing block 40 is pressed against the inner sidewall of the lower groove 35, the middle of the lower sealing block 40 is formed with a vertical through hole, the vertical through hole communicates with the vertical valve hole 31, and the bottom surface of the lower sealing block 40 is pressed against the top surface of the annular boss 15 and covers the top of the valve port 151.

Further, the top surface of the edge of the piston block 30 is formed with an edge bulge extending upwards, the lower part of the sleeve 50 is clamped on the inner side wall of the upper large diameter hole section of the piston guiding stepped through hole 21, the bottom surface of the edge of the bottom plate of the sleeve 50 is pressed against the bottom surface of the upper large diameter hole section of the piston guiding stepped through hole 21, the static iron core 60 is fixed on the upper inner side wall of the sleeve 50, the movable iron core 70 is inserted in the lower part of the sleeve 50, the outer side wall of the movable iron core 70 is close to the inner side wall of the sleeve 50, the middle part of the bottom surface of the movable iron core 70 is formed with an extending bulge column 71 extending downwards, the bottom of the extending bulge column 71 extends out of the middle through hole of the bottom plate of the sleeve 50, the middle part of the top surface of the movable iron core 70 is formed with a central stepped through hole 72 extending downwards vertically, the bottom end of the first spring 1 is inserted in the upper large diameter hole section of the central stepped through hole 72, the bottom end of the first spring 1 is forced on the bottom surface of the upper large diameter hole section of the central stepped through hole 72, and the top end of the first spring 1 is forced on the bottom surface of the static iron core 60;

the piston guide stepped through hole 21 of the small valve seat 20 can ensure that the piston block 30 stably ascends and descends through the middle transition hole section without colliding with the sleeve 50, and the movement stability of the piston block is improved.

The bottom plate edge of the sleeve 50 corresponds up and down to the edge bulge formed on the top surface of the edge of the piston block 30, and limits the stroke of the piston block 30.

The middle part of the bottom surface of the extending protruding column 71 is formed with an upwardly extending buffer concave hole, in which an upper sealing block 79 is installed, and the bottom surface of the upper sealing block 79 is pressed against the top surface of the middle part of the piston block 30 and covers the top end of the vertical valve hole 31.

Further, a radially extending annular groove 711 is formed on the inner side wall of the lower portion of the buffering concave hole, the guide sleeve 73 is inserted into the buffering concave hole, the edge portion of a radially extending edge 731 formed on the outer side wall of the bottom end of the guide sleeve 73 is inserted into the radially extending annular groove 711, the outer side wall of the radially extending edge 731 is clamped on the inner side wall of the radially extending annular groove 711 through interference fit, the bottom side plate of the radially extending annular groove 711 can be bent inwards through extrusion to realize riveting fixation, the top surface of the bottom side plate is pressed against the edge bottom surface of the radially extending edge of the guide sleeve 73, and the fixing is realized in a conventional fixing mode, which is not described in detail herein, and is not shown in the drawing; the outer side wall of the guide sleeve 73 is inserted with a buffer spring 74, the bottom end of the buffer spring 74 is applied to the top surface of the radial edge 731 of the guide sleeve 73, the upper sealing block 79 is inserted into the central through hole of the guide sleeve 73, the bottom end of the upper sealing block 79 extends out of the bottom surface of the guide sleeve 73, the top of the upper sealing block 79 is formed with an upper limiting part 75 with the outer diameter larger than that of the upper sealing block 79, the upper limiting part 75 is positioned above the guide sleeve 73, the top end of the buffer spring 74 is applied to the bottom surface of the upper limiting part 75, and the top surface of the upper limiting part 75 faces the bottom end of the lower small-diameter hole section of the central stepped through hole 72;

the bottom surface of the edge of the extending protruding column 71 faces the upper annular diversion trench 32.

The buffer spring 74 and the upper sealing block 79 are guided by the guide sleeve 73 in a spaced manner, so that the normal use of the buffer spring 74 is ensured, the stable operation of the upper sealing block 79 is also ensured, the buffer spring 74 does not directly act on the piston block 30, the normal operation of the piston block 30 is ensured, the piston block 30 is not easy to damage, and the service life is ensured.

The buffer spring 74 can provide a buffer effect when the upper seal block 79 moves up and down.

The lower seal block 40 and the upper seal block 79 in this embodiment may be an elastomeric seal block or a ceramic seal block or other known seal blocks, which will not be described in detail herein.

Further, the central stepped through hole 72 has a radial through hole formed in the inner side wall of the middle part of the lower small diameter hole section, and the vertical valve hole 31 is a stepped through hole with a larger lower diameter and a smaller upper diameter.

Working principle: an electromagnetic coil (the electromagnetic coil in the drawing is a simple illustration) is fixed to the upper outer side wall of the sleeve 50.

After the electromagnetic coil is electrified and opened, the static iron core 60 adsorbs the movable iron core 70, so that the first spring 1 is compressed, the movable iron core 70 is lifted, the upper sealing block 79 is driven to be lifted, the top end of the vertical valve hole 31 is not tightly covered by the upper sealing block 79, at the moment, the pressure of the upper part of the piston block 30 is lower than that of the lower part of the piston block 30, liquid entering from the liquid inlet 11 is positioned in the lower part of the first stepped hole 14, the piston block 30 is pushed upwards, at the moment, the lower sealing block 40 is lifted, the top of the valve port 151 is not covered any more, and the liquid enters into the valve port 151 from the lower part of the first stepped hole 14 and flows out from the liquid outlet 12, so that communication is realized.

When the electromagnetic coil is powered off, the static iron core 60 releases the movable iron core 70, the first spring 1 returns, the movable iron core 70 descends, the upper sealing block 79 descends, the bottom surface of the upper sealing block covers the top end of the vertical valve hole 31, meanwhile, liquid at the upper part of the piston block 30 enters the vertical diversion hole 33 through the upper annular diversion groove 32, then enters the radial diversion hole 34, finally reaches the diversion annular groove 22, the pressure difference between the upper side and the lower side of the piston block 30 is balanced, and the lower sealing block 40 descends and covers the valve port 151 to cut off the liquid outlet 12 and the liquid inlet 11 under the elastic return action of the first spring 1.

Claims (6)

1. The utility model provides an eliminate idle stroke structure of guide's formula solenoid valve, includes valve body and piston piece (30), its characterized in that: the top surface of the middle part of the valve body is provided with a piston guide stepped through hole (21) which extends vertically and downwards, a piston block (30) is inserted into the middle part of the piston guide stepped through hole (21), a sleeve (50) is clamped at the upper part of the piston guide stepped through hole (21), a movable iron core (70) is inserted into the lower part of the sleeve (50), the middle part of the bottom surface of the movable iron core (70) is provided with an extending convex column (71) which extends downwards, and the bottom of the extending convex column (71) extends out of the middle through hole of the bottom plate of the sleeve (50); the middle part shaping of the bottom surface of extension protruding post (71) has the buffering shrinkage pool that upwards extends, install uide bushing (73) in the buffering shrinkage pool, upper portion sealing block (79) plug bush is in uide bushing (73), the bottom of uide bushing (73) is stretched out to the bottom of upper portion sealing block (79) and is pressed on the middle part top surface of piston block (30), buffering spring (74) plug bush is on uide bushing (73) and be in the buffering shrinkage pool, the top shaping of upper portion sealing block (79) has upper limit portion (75) that the external diameter is greater than upper portion sealing block (79), upper limit portion (75) are in the top of uide bushing (73), the top of buffering spring (74) is exerted on the bottom surface of upper limit portion (75), the bottom of buffering spring (74) is exerted in the lower part of uide bushing (73).

2. The idle stroke elimination structure of a pilot operated solenoid valve according to claim 1, wherein: the valve body comprises a large valve seat (10) and a small valve seat (20), a first stepped hole (14) extending downwards is formed in the middle of the top surface of the large valve seat (10), the lower portion of the small valve seat (20) is located at the upper portion of the first stepped hole (14) and is fixedly installed, and a piston guide stepped through hole (21) extending vertically is formed in the middle of the small valve seat (20).

3. The idle stroke elimination structure of a pilot operated solenoid valve according to claim 2, wherein: the lower part inside wall of buffering shrinkage pool is last to be formed with radial extension ring channel (711), and uide bushing (73) plug bush is in the buffering shrinkage pool, and the limit portion plug bush of fashioned radial limit (731) on the bottom lateral wall of uide bushing (73) is in radial extension ring channel (711), and the lateral wall card of radial limit (731) is put on the inside wall of radial extension ring channel (711), and the bottom curb plate of radial extension ring channel (711) extends downwards, and its bottom is less than the bottom surface of radial limit (731).

4. The idle stroke elimination structure of a pilot operated solenoid valve according to claim 1, wherein: the outer side wall of the guide sleeve (73) is inserted with a buffer spring (74), and the bottom end of the buffer spring (74) is applied to the top surface of the radial edge (731) of the guide sleeve (73).

5. The idle stroke elimination structure of a pilot operated solenoid valve according to claim 1, wherein: the top surface side shaping of piston piece (30) has last annular guiding gutter (32), and the top surface side shaping of piston piece (30) of the outside department of going up annular guiding gutter (32) has the limit portion arch that upwards extends, and the limit portion bottom surface of the bottom plate of sleeve pipe (50) is protruding towards the limit portion.

6. The idle stroke elimination structure of a pilot operated solenoid valve according to claim 5, wherein: the upper annular diversion trench (32) faces the bottom surface of the bottom side plate of the radial extension annular groove (711).