CN215763422U

CN215763422U - Duplex electromagnetic valve

Info

Publication number: CN215763422U
Application number: CN202122034484.XU
Authority: CN
Inventors: 陈卫华; 单军波; 单晓荣; 严瑞康; 周海威; 周陈鑫
Original assignee: NINGBO JIAERLING PNEUMATIC MACHINERY CO Ltd
Current assignee: NINGBO JIAERLING PNEUMATIC MACHINERY CO Ltd
Priority date: 2021-08-27
Filing date: 2021-08-27
Publication date: 2022-02-08
Anticipated expiration: 2031-08-27

Abstract

The utility model discloses a duplex solenoid valve, which comprises a valve body, wherein the valve body is provided with a plurality of solenoid valve assemblies, each solenoid valve assembly comprises a first end cover and a second end cover, and the first end covers are provided with pilot heads in one-to-one correspondence; at least two valve cavities are arranged in the valve body, and the electromagnetic valve assembly further comprises a valve rod; the valve body is provided with an air inlet, a first working port, a second working port, a first exhaust port and a second exhaust port which are communicated with the same valve cavity, the same air inlet is communicated with the valve cavity, the valve rod is sleeved with a spacer bush, the spacer bush comprises a first spacer bush, a second spacer bush, a third spacer bush and a fourth spacer bush, and an avoidance gap is formed between every two adjacent spacer bushes; a first air channel structure is arranged in the first end cover, and a second air channel structure is arranged in the second end cover. The utility model adopts the mode of arranging the plurality of electromagnetic valve components on the same valve body, and the same air inlet is used for inflating the plurality of valve cavities, so that the integral occupied volume is smaller in the use process, the pipelines are orderly and convenient to install.

Description

Duplex electromagnetic valve

Technical Field

The utility model relates to the technical field of electromagnetic valves, in particular to a duplex electromagnetic valve.

Background

The electromagnetic valve is an industrial device controlled by electromagnetism, is an automatic basic element for controlling fluid, belongs to an actuator, is not limited to hydraulic pressure and pneumatic pressure, and is used for adjusting the direction, flow rate, speed and other parameters of a medium in an industrial control system.

The common pair solenoid valve on the market usually adopts the mode of being fixed in two solenoid valves respectively in the cylinder manifold to carry out integrated form installation, so, has following shortcoming: firstly, a bus board needs to be configured independently, so that the problem of inconvenient production and installation exists; and secondly, the volume is larger, the weight is larger and the cost is higher after the installation.

SUMMERY OF THE UTILITY MODEL

The utility model aims to provide a duplex electromagnetic valve, which integrates and installs two electromagnetic valve components on the same valve body and has the effects of convenient installation and small volume.

The technical purpose of the utility model is realized by the following technical scheme: a duplex electromagnetic valve comprises a valve body, wherein a plurality of electromagnetic valve components are arranged on the valve body in parallel, each electromagnetic valve component comprises a first end cover arranged at one end of the valve body and a second end cover correspondingly arranged at the other end of the valve body, and the first end covers are provided with pilot heads in a one-to-one correspondence manner;

the valve body is internally provided with at least two valve cavities, and the electromagnetic valve assembly further comprises a valve rod movably arranged in the valve cavities; the valve body is provided with an air inlet, a first working port, a second working port, a first exhaust port and a second exhaust port which are communicated with the same valve cavity, the same air inlet is communicated with a plurality of valve cavities, a plurality of spacer bushes are sleeved on the valve rod and comprise a first spacer bush, a second spacer bush, a third spacer bush and a fourth spacer bush, and an avoiding gap for air flow to pass through is formed between every two adjacent spacer bushes;

a first air channel structure is arranged in the first end cover, a second air channel structure is arranged in the second end cover, the first air channel structure is in on-off fit with the pilot head, and the first air channel structure and the second air channel structure are matched to control the valve rod to move along the axial direction;

when the first spacer bush and the third spacer bush are in sealing fit with the valve cavity, the air inlet is communicated with the first working port, and the second working port is communicated with the second exhaust port; when the second spacer bush and the fourth spacer bush are in sealing fit with the valve cavity, the air inlet is communicated with the second working port, and the first working port is communicated with the first exhaust port.

By adopting the technical scheme, during installation, the valve rods are installed in the valve cavities in a one-to-one correspondence mode, and the first end cover and the second end cover are installed at two ends of the valve body respectively in a corresponding mode. In a normal state, air is fed through the air inlet, the air inlet respectively inflates air into the first air passage structure and the second air passage structure, after the coil assembly of the guide head is electrified, the first air passage structure is ventilated, the valve rod can be pushed to move towards a direction far away from the first end cover, when the valve rod moves to be closest to the second end cover, the first spacer bush and the third spacer bush are abutted against the inner wall of the valve cavity and are in sealing fit, the second spacer bush is correspondingly positioned at the air inlet, the fourth spacer bush is correspondingly positioned at the second air outlet, at the moment, the air inlet is communicated with the first working port, the external equipment can be inflated, and the second working port is communicated with the second air outlet to realize an air exhaust process; after the coil pack outage of leading head, make first air flue structure close and stop admitting air, and the second air flue structure lasts to admit air, can push the valve rod and remove to the direction of keeping away from the second end cover, when second spacer sleeve and fourth spacer sleeve all offset sealed fit with the valve pocket inner wall, first spacer sleeve corresponds and is located first exhaust port department, the third spacer sleeve corresponds and is located air inlet department, at this moment, the air inlet is linked together with the second work port, can aerify external equipment, first work port is linked together with first exhaust port, realize the exhaust process. At the in-process of admitting air, the same air inlet of accessible is aerifyd to a plurality of valve intracavity of valve body for a plurality of solenoid valve subassembly simultaneous workings on the valve body, so, not only whole shared volume is less in the use, need not to connect many admission lines respectively at a plurality of air inlets, and the pipeline is neat orderly, and the installation is also more convenient moreover.

The utility model is further provided with: the first air passage structure comprises a first air inlet passage, the first end cover is provided with a cavity, the first air inlet passage is arranged between the air inlet and the cavity, and the cavity is communicated with the valve cavity.

Through adopting above-mentioned technical scheme, the air inlet can be aerifyd in the cavity of first end cover through first inlet channel, and the displacement of valve rod can be pushed to atmospheric pressure in the cavity.

The utility model is further provided with: the cavity comprises an inner cavity and an outer cavity, the end part of the valve rod is provided with a piston, the piston is movably arranged in the inner cavity, the inner cavity is divided into a rod cavity and a rodless cavity by the piston, the first end cover is provided with an exhaust groove communicated with the rod cavity, and the rod cavity is communicated with the atmosphere through the exhaust groove; a communicating hole is formed between the rodless cavity and the outer cavity, a plug positioned in the outer cavity is arranged on the first end cover, and an air passage is formed in the plug; the pilot head comprises a coil assembly, an electromagnetic block assembly and a return spring, and is provided with an exhaust passage communicated with the outer side cavity;

when the coil assembly is electrified to adsorb the electromagnetic block assembly, the first air inlet channel is communicated with the outer side cavity through the air passage, and the air outlet channel is blocked; when the coil assembly is powered off, the reset spring drives the electromagnetic block assembly to abut against the plug, and the outer side cavity is communicated with the atmosphere through the exhaust channel.

By adopting the technical scheme, when the guide head is electrified, the electromagnetic block assembly is adsorbed, the air passage is communicated with the outer side chamber, the air flow of the first air inlet channel can pass through the outer side chamber and then is introduced into the rodless cavity of the inner side chamber through the communication hole, so that the piston can be pushed to move, the gas in the rod cavity can be discharged from the exhaust groove, and the exhaust channel is blocked by the electromagnetic block assembly in the process; when the guide head loses power, the reset spring orders about the electromagnetic block assembly to abut against the plug, one end of the air passage is blocked, so that the first air inlet passage and the outer side cavity are cut off, the other end of the electromagnetic block assembly is far away from the exhaust passage, and the outer side cavity can be communicated with the atmosphere of the external environment through the exhaust passage.

The utility model is further provided with: the end of the valve rod is provided with a piston which is movably arranged in the inner chamber, and the sectional area S1 of the piston is larger than the sectional area S2 of the valve rod.

By adopting the technical scheme, under the condition that the air pressure is the same, the stress area is in direct proportion to the pressure, and the stress areas at the two ends of the valve rod are different, namely the sectional area S1 of the piston is larger than the sectional area S2 of the valve rod, so that when the air inlet inflates the first air inlet channel and the second air inlet channel respectively, the stress at the end of the piston is larger, and the valve rod can be pushed to move towards the direction far away from the first end cover.

The utility model is further provided with: the second air flue structure includes the second inlet channel, and the second end cover is opened and is equipped with and hold the chamber, and the second inlet channel is located the air inlet and is held between the chamber, holds the intracavity and is equipped with the elastic component, and the elastic component makes the valve rod have the trend to keeping away from second end cover direction motion all the time.

Through adopting above-mentioned technical scheme, when the valve rod was to the displacement of second end cover, the elastic component was compressed, and the elastic component can play supplementary effect that promotes to a certain extent.

The utility model is further provided with: the elastic piece is set to be a thrust spring, one end of the thrust spring is abutted to the valve rod, and the other end of the thrust spring is abutted to the second end cover.

The utility model is further provided with: a limit post is arranged in the second end cover, and the thrust spring is sleeved on the limit post.

Through adopting above-mentioned technical scheme, spacing post can play better limiting displacement to thrust spring, prevents that spacing post from taking place relative displacement at flexible in-process.

The utility model is further provided with: the side walls of the two ends of the valve rod are respectively provided with a sealing ring, and the side walls of the two ends of the valve rod are in sealing fit with the valve cavity through the sealing rings, so that the valve cavity is separated from the cavity of the first end cover.

Through adopting above-mentioned technical scheme, the sealing washer is passed through at the both ends of valve rod and the sealed cooperation of valve pocket, can prevent to a certain extent that the gas in the valve pocket from leaking to first end cover, second end cover.

The utility model is further provided with: the valve body is internally provided with a main channel, a first branch channel and a second branch channel which are communicated with the air inlet, and when the coil assembly is electrified to adsorb the electromagnetic block assembly, the first branch channel is communicated with the inner cavity of the first end cover; the second branch channel is always communicated with the inner cavity of the second end cover.

Through adopting above-mentioned technical scheme, the air current of air inlet flows to first branch passageway and second branch passageway respectively through the main entrance, and then aerifys the inner chamber of first end cover and the inner chamber of second end cover.

The utility model is further provided with: the first working port and the first exhaust port are located on one side of the air inlet, and the second working port and the second exhaust port are located on the other side of the air inlet.

In conclusion, the utility model has the following beneficial effects:

1. the mode that the plurality of electromagnetic valve assemblies are arranged on the same valve body is adopted, and the plurality of valve cavities are inflated by the same air inlet, so that the plurality of electromagnetic valve assemblies on the valve body work simultaneously, therefore, the whole occupied volume is small in the using process, a plurality of air inlet pipelines are not required to be connected with the plurality of air inlets respectively, the pipelines are orderly, and the installation process is more convenient;

2. the mode of arranging an elastic piece which is propped against the valve rod in the second end cover is adopted, and the auxiliary pushing effect can be achieved to a certain extent;

3. the mode that sets up the sealing washer at the both ends of valve rod is adopted, can prevent to a certain extent that the gas in the valve chamber from leaking to first end cover, second end cover.

Drawings

Fig. 1 is a schematic diagram of the overall structural relationship of the embodiment.

Fig. 2 is a top view of the embodiment.

Fig. 3 is a cross-sectional view of section a-a of fig. 2 with the valve stem in a relatively right-shifted state.

Fig. 4 is a cross-sectional view of section a-a of fig. 2 with the valve stem in a relatively leftward displaced state.

Fig. 5 is a side view of the embodiment.

Fig. 6 is a sectional view of section B-B in fig. 5.

Fig. 7 is a cross-sectional view of section C-C in fig. 2.

Fig. 8 is an air path diagram of the embodiment.

In the figure: 1. a valve body; 11. a first end cap; 111. a first air intake passage; 112. an inner chamber; 1121. a rod cavity; 1122. a rodless cavity; 113. an outer chamber; 114. a communicating hole; 115. a plug; 116. an airway; 117. an exhaust groove; 12. a second end cap; 121. a second intake passage; 122. a limiting column; 123. an accommodating chamber; 13. a valve cavity; 131. a first convex ring; 132. a second convex ring; 133. a third convex ring; 134. a fourth convex ring; 14. an air inlet; 141. a main channel; 142. a first branch channel; 143. a second branch channel; 15. a first working port; 16. a second working port; 17. a first exhaust port; 18. a second exhaust port; 2. a leading head; 21. a coil assembly; 22. an electromagnetic block assembly; 221. a sealing plug; 23. a return spring; 24. an exhaust passage; 3. a valve stem; 31. a first spacer sleeve; 32. a second spacer sleeve; 33. a third spacer sleeve; 34. a fourth spacer sleeve; 35. a seal ring; 36. avoiding the gap; 37. a piston; 38. a guide ring; 4. a thrust spring; 5. a nut; 51. and (4) air holes.

Detailed Description

The utility model will be further described with reference to the accompanying drawings. For convenience of explanation, the following "left" and "right" are both in the same direction as shown in fig. 1.

A duplex electromagnetic valve, as shown in FIGS. 1-3, comprises a valve body 1, two electromagnetic valve assemblies are arranged on the valve body 1 in parallel, each electromagnetic valve assembly comprises a first end cover 11 arranged at the right end of the valve body 1 and a second end cover 12 correspondingly arranged at the left end of the valve body 1, the first end covers 11 are provided with pilot heads 2 in one-to-one correspondence, each pilot head 2 comprises a coil assembly 21, an electromagnetic block assembly 22 and a reset spring 23, the electromagnetic block assembly 22 is provided with a sealing plug 221, an exhaust passage 24 communicated with an outer chamber 113 is arranged on the coil assembly 21 and the electromagnetic block assembly 22, a nut 4 is in threaded connection with the coil assembly 21, an air hole 51 communicated with the exhaust passage 24 is arranged on the nut 4, and the outer chamber 113 can be communicated with the atmosphere through the air hole 51.

As shown in fig. 1-3, two adjacent valve cavities 13 are formed in the valve body 1, the solenoid valve assembly further includes a valve rod 3 movably disposed in the valve cavities 13, side walls of two ends of the valve rod 3 are respectively provided with a sealing ring 35 and a guide ring 38, side walls of two ends of the valve rod 3 are in sealing fit with the valve cavities 13 through the sealing rings 35, two ends of the valve rod 3 enable the valve cavities 13 to be separated from inner cavities of the first end cover 11 and the second end cover 12 through the sealing rings 35, and gas in the valve cavities 13 can be prevented from leaking to the first end cover 11 and the second end cover 12 to a certain extent.

As shown in fig. 1-3, 5 and 6, the valve body 1 is provided with an air inlet 14, a first working port 15, a second working port 16, a first exhaust port 17 and a second exhaust port 18 which are communicated with the same valve chamber 13, the first working port 15 and the first exhaust port 17 are positioned on the right side of the air inlet 14, and the second working port 16 and the second exhaust port 18 are positioned on the left side of the air inlet 14. The valve body 1 is provided with a main channel 141, a first branch channel 142 and a second branch channel 143 which are communicated with the air inlet 14, the first branch channel 142 is communicated with the inner cavity of the first end cover 11, the second branch channel 143 is communicated with the inner cavity of the second end cover 12, the air flow of the air inlet 14 flows to the first branch channel 142 and the second branch channel 143 through the main channel 141 respectively, and then the inner cavity of the first end cover 11 and the inner cavity of the second end cover 12 are inflated. An air inlet 14 is arranged on the valve body 1, and the same air inlet 14 is communicated with two adjacent valve cavities 13.

As shown in fig. 3-4, a plurality of spacer bushes are sequentially sleeved on the valve rod 3 along the axial direction, each spacer bush comprises a first spacer bush 31, a second spacer bush 32, a third spacer bush 33 and a fourth spacer bush 34 which are sequentially arranged from right to left, and an avoiding gap 36 for air flow to pass through is formed between every two adjacent spacer bushes; the inner wall of the valve cavity 13 is correspondingly provided with a first convex ring 131, a second convex ring 132, a third convex ring 133 and a fourth convex ring 134 from right to left.

As shown in fig. 3 and 5-7, a first air channel structure is disposed in the first end cap 11, the first air channel structure includes a first air inlet channel 111 communicated with the air inlet 14, the first end cap 11 is provided with a cavity, the cavity includes an inner cavity 112 and an outer cavity 113, a communication hole 114 is disposed between the inner cavity 112 and the outer cavity 113, the first end cap 11 is provided with a plug 115 located in the outer cavity 113, the plug 115 is provided with an air channel 116, the air channel 116 is communicated with the first air inlet channel 111, the air channel 116 is matched with the electromagnetic block assembly 22 of the pilot head 2, the first air inlet channel 111 is communicated with the first branch channel 142, when the plug 115 abuts against the electromagnetic block assembly 22 of the pilot head 2, one end of the air channel 116 is blocked, so that the first air inlet channel 111 and the outer cavity 113 are cut off, when the electromagnetic block assembly 22 of the pilot head 2 is far away from the plug 115, the first air inlet channel 111 is communicated with the outer cavity 113, the air flow in the outer chamber 113 is then communicated to the inner chamber 112 through the communication hole 114. A piston 37 is arranged at the right end of the valve rod 3, the piston 37 is movably arranged in the inner side chamber 112, the piston 37 is in sealing fit with the inner side chamber 112, the inner side chamber 112 is divided into a rod cavity 1121 and a rodless cavity 1122 by the piston 37, an exhaust groove 117 communicated with the rod cavity 1121 is formed in the lower side wall of the first end cover 11, and the rod cavity 1121 is communicated with the atmosphere through the exhaust groove 117; the sectional area S1 of the piston 37 is greater than the sectional area S2 of the valve rod 3, the force-receiving area is proportional to the pressure under the same air pressure, and the force-receiving areas at the two ends of the valve rod 3 are different, that is, the sectional area S1 of the piston 37 is greater than the sectional area S2 of the left end of the valve rod 3, so that when the air inlet 14 charges the air into the first air inlet passage 111 and the second air inlet passage 121, the force received by the piston end is greater, and the valve rod 3 is pushed to move away from the first end cap 11.

As shown in fig. 3 and 6, a second air passage structure is arranged in the second end cover 12, the second air passage structure includes a second air inlet channel 121, the second end cover 12 is provided with a containing cavity 123, an elastic member is arranged in the containing cavity 123, the elastic member is set to be a thrust spring 4, one end of the thrust spring 4 is abutted against the valve rod 3, the other end of the thrust spring 4 is abutted against the second end cover 12, the thrust spring 4 enables the valve rod 3 to always have a trend of moving in a direction away from the second end cover 12, a limiting column 122 is arranged in the second end cover 12, and the limiting column 122 is sleeved with the thrust spring 4. When the valve rod 3 is displaced towards the second end cover 12, the thrust spring 4 is compressed, and the thrust spring 4 can play a role in assisting pushing to a certain extent. The limiting column 122 can well limit the thrust spring 4, and relative displacement of the limiting column 122 in the telescopic process is prevented.

The basic working principle of the utility model is as follows: during installation, the valve rods 3 are correspondingly installed in the valve cavity 13 one by one, and the first end cover 11 and the second end cover 12 are correspondingly installed on two sides of the valve body 1 respectively.

In a normal state, air is fed through the air inlet 14, the air inlet 14 respectively inflates air into the first air channel structure and the second air channel structure (the air path schematic diagram can refer to fig. 8), when the coil assembly 21 of the guide head 2 is electrified to adsorb the electromagnetic block assembly 22, the first air channel structure is ventilated, the air channel 116 is communicated with the outer chamber 113, the air flow of the first air inlet channel can pass through the outer chamber 113 and then is introduced into the rodless chamber 1122 of the inner chamber 112 through the communication hole 114, the valve rod 3 can be pushed to move in a direction away from the first end cover 11, the air in the rod chamber 1121 can be discharged from the exhaust groove 117, and the exhaust channel 24 is blocked by the electromagnetic block assembly 22 in the process; when the valve rod 3 is displaced to the left to be closest to the second end cover 12, the first spacer 31 and the third spacer 33 are respectively abutted against and in sealing fit with the first convex ring 131 and the third convex ring 133 on the inner wall of the valve cavity 13, the second spacer 32 is correspondingly positioned at the air inlet 14, the fourth spacer 34 is correspondingly positioned at the second exhaust port 18, at the moment, the air inlet 14 is communicated with the first working port 15, the external equipment can be inflated, and the second working port 16 is communicated with the second exhaust port 18, so that the exhaust process is realized.

After the coil assembly 21 of the pilot head 2 is powered off, under the elastic force of the return spring 23, the electromagnetic block assembly 22 abuts against the plug 115, so that the first air passage 116 is structurally closed to stop air intake, and in the process, the exhaust passage 24 is communicated with the outer chamber 113, so that the air in the outer chamber 113 can be exhausted to the atmosphere of the external environment through the exhaust passage 24 and the air hole 51; the structure of the second air passage 116 continuously admits air, that is, the valve rod 3 can move rightwards under the pushing action of the air pressure and the thrust spring 4, when the second spacer 32 and the fourth spacer 34 are respectively abutted against and in sealing fit with the second convex ring 132 and the fourth convex ring 134 on the inner wall of the valve cavity 13, the first spacer 31 is correspondingly positioned at the first exhaust port 17, the third spacer 33 is correspondingly positioned at the air inlet 14, at the moment, the air inlet 14 is communicated with the second working port 16, that is, the external equipment can be inflated, and the first working port 15 is communicated with the first exhaust port 17, so that the exhaust process is realized. In the air inlet process, the same air inlet 14 of accessible is aerifyd in to a plurality of valve chambeies 13 of valve body 1 for a plurality of solenoid valve subassembly simultaneous working on the valve body 1, so, not only whole shared volume is less in the use, need not to connect many admission lines respectively at a plurality of air inlets 14, and the pipeline is neat orderly, and the installation is also more convenient moreover.

The above description is only a preferred embodiment of the present invention, and all equivalent changes or modifications of the structure, characteristics and principles described in the present invention are included in the scope of the present invention.

Claims

1. The utility model provides a pair solenoid valve, including valve body (1), its characterized in that: a plurality of electromagnetic valve assemblies are arranged on the valve body (1) in parallel, each electromagnetic valve assembly comprises a first end cover (11) arranged at one end of the valve body (1) and a second end cover (12) correspondingly arranged at the other end of the valve body (1), and the first end covers (11) are provided with guide heads (2) in a one-to-one correspondence manner;

at least two valve cavities (13) are formed in the valve body (1), and the electromagnetic valve assembly further comprises a valve rod (3) movably arranged in the valve cavities (13); the valve body (1) is provided with an air inlet (14), a first working port (15), a second working port (16), a first exhaust port (17) and a second exhaust port (18) which are communicated with the same valve cavity (13), the same air inlet (14) is communicated with a plurality of valve cavities (13), a plurality of spacers are sleeved on the valve rod (3), each spacer comprises a first spacer (31), a second spacer (32), a third spacer (33) and a fourth spacer (34), and an avoidance gap (36) for air flow to pass through is formed between every two adjacent spacers;

a first air channel structure is arranged in the first end cover (11), a second air channel structure is arranged in the second end cover (12), the first air channel structure is in on-off fit with the guide head (2), and the first air channel structure and the second air channel structure are matched to control the valve rod (3) to axially displace;

when the first spacer sleeve (31) and the third spacer sleeve (33) are in sealing fit with the valve cavity (13), the air inlet (14) is communicated with the first working port (15), and the second working port (16) is communicated with the second air outlet (18); when the second spacer sleeve (32) and the fourth spacer sleeve (34) are in sealing fit with the valve cavity (13), the air inlet (14) is communicated with the second working port (16), and the first working port (15) is communicated with the first exhaust port (17).

2. A twin solenoid valve as defined in claim 1 wherein: the first air channel structure comprises a first air inlet channel (111), a cavity is formed in the first end cover (11), the first air inlet channel (111) is arranged between the air inlet (14) and the cavity, and the cavity is communicated with the valve cavity (13).

3. A twin solenoid valve as defined in claim 2 wherein: the cavity comprises an inner cavity (112) and an outer cavity (113), a piston (37) is arranged at the end of the valve rod (3), the piston (37) is movably arranged in the inner cavity (112), the inner cavity (112) is divided into a rod cavity (1121) and a rodless cavity (1122) by the piston (37), an exhaust groove (117) communicated with the rod cavity (1121) is formed in the first end cover (11), and the rod cavity (1121) is communicated with the atmosphere through the exhaust groove (117); a communication hole (114) is formed between the rodless cavity (1122) and the outer side cavity (113), a plug (115) located in the outer side cavity (113) is arranged on the first end cover (11), and an air channel (116) is formed in the plug (115); the guide head (2) comprises a coil assembly (21), an electromagnetic block assembly (22) and a return spring (23), and the guide head (2) is provided with an exhaust passage (24) communicated with the outer side cavity (113);

when the coil assembly (21) is electrified to adsorb the electromagnetic block assembly (22), the first air inlet channel (111) is communicated with an outer side chamber (113) through the air channel (116), and the air outlet channel (24) is blocked; when the coil assembly (21) is powered off, the return spring (23) drives the electromagnetic block assembly to abut against the choke plug (115), and the outer side cavity (113) is communicated with the atmosphere through the exhaust channel (24).

4. A twin solenoid valve as defined in claim 3 wherein: the sectional area S1 of the piston (37) is larger than the sectional area S2 of the valve rod (3).

5. A twin solenoid valve as defined in claim 1 wherein: the second air passage structure comprises a second air inlet channel (121), an accommodating cavity (123) is formed in the second end cover (12), the second air inlet channel (121) is arranged between the air inlet (14) and the accommodating cavity (123), an elastic piece is arranged in the accommodating cavity (123), and the elastic piece enables the valve rod (3) to always have a trend of moving towards the direction far away from the second end cover (12).

6. A twin solenoid valve as defined in claim 5 wherein: the elastic piece is arranged to be a thrust spring (4), one end of the thrust spring (4) abuts against the valve rod (3), and the other end of the thrust spring (4) abuts against the second end cover (12).

7. A twin solenoid valve as defined in claim 6 wherein: a limiting column (122) is arranged in the second end cover (12), and the thrust spring (4) is sleeved on the limiting column (122).

8. A twin solenoid valve as defined in claim 2 wherein: the lateral walls of the two ends of the valve rod (3) are respectively provided with a sealing ring (35), and the lateral walls of the two ends of the valve rod (3) are in sealing fit with the valve cavity (13) through the sealing rings (35), so that the valve cavity (13) is separated from the cavity of the first end cover (11).

9. A twin solenoid valve as defined in claim 3 wherein: a main channel (141), a first branch channel (142) and a second branch channel (143) which are communicated with the air inlet (14) are formed in the valve body (1), and when the coil assembly (21) is electrified to adsorb the electromagnetic block assembly (22), the first branch channel (142) is communicated with an inner cavity of the first end cover (11); the second branch channel (143) is always communicated with the inner cavity of the second end cover (12).

10. A twin solenoid valve as defined in claim 1 wherein: the first working port (15) and the first exhaust port (17) are located on one side of the air inlet (14), and the second working port (16) and the second exhaust port (18) are located on the other side of the air inlet (14).