Positive and negative pressure dual-purpose reversing valve with pressure maintaining function

Abstract

The invention relates to the technical field of reversing valves, in particular to a positive and negative pressure dual-purpose reversing valve with a pressure maintaining function, which comprises a valve body combination, a valve rod, two pistons, two groups of coil racks and iron cores and a first spring, the two piston cavities, the two outer air cavities, the two outer air channels, the third air inlet and the circulation channel are communicated with the first air inlet, the second air inlet, the air outlet and the two sliding cavities respectively, each sliding cavity is communicated with one piston cavity, the other end of each sliding cavity is communicated with the corresponding outer air cavity, the outer air channels are communicated with the outer air cavities and the third air inlet, and the valve rod is arranged in the two sliding cavities and the circulation channel in a sliding mode. According to the invention, the first spring and the third air inlet are arranged, so that the advantage that the two air inlets are separated from the air outlet in a power-off state is realized.

Description

Technical Field

[0001] The present application relates to the technical field of reversing valves, and more specifically to a positive and negative pressure dual-purpose reversing valve with a pressure-maintaining function. Background Art

[0002] A reversing valve is a directional control valve with more than two flow forms and more than two oil ports.

[0003] There is a two-inlet-one-outlet reversing valve 9, such as Figure 1 As shown, it includes a pump body 90, a valve stem 91 and two pistons 92. The pump body 90 has two air inlets 901, an air outlet 902, a connecting cavity 903, two piston cavities 904 and two pneumatic inlets 905. The two pneumatic inlets 905 are both connected to an external air source device (not shown in the figure). The valve stem 91 is slidably arranged in the connecting cavity 903, and the two ends of the valve stem 91 extend into the two piston cavities 904 by a predetermined distance. A blocking ring is arranged on the valve stem 91, and gas is filled into one of the pneumatic inlets 905 through an external air source device. When gas flows into one of the pneumatic inlets 905, the corresponding piston 92 moves toward the valve stem 91 under the action of air pressure, and pushes the valve stem 91 to move in the corresponding direction, and at a certain moment blocks the connection between one of the air inlets 901 and the connecting cavity 903, so that only one of the air inlets 901 and one of the air outlets 902 are connected at the same time. However: in the case of Figure 2 In the application scenario, it is assumed that two gases are to be filled into the bottle 93. After each gas is filled to a predetermined pressure value, it needs to be left to stand for a predetermined time before another gas is filled. Figure 1 When no gas flows into the two pneumatic inlets 905 of the two-inlet-one-outlet reversing valve 9 to push the piston 92, since one of the air inlets 901 is still connected to the air outlet 902, that is, the external air source can still flow along the air inlet 901 to the air outlet 902 and fill the bottle body 93. Therefore, it is impossible to achieve the isolation of the external air source and the bottle body 93 and stabilize the air pressure in the bottle body 93 by stopping the external air source device of the two-inlet-one-out reversing valve 9 after the air pressure in the bottle body 93 reaches a certain value.

[0004] Therefore, there is a need to provide a positive and negative pressure dual-purpose reversing valve with a leak-proof seal and a pressure-maintaining function, in which the two air inlets and outlets are isolated in a power-off state, and the air source pressure at the air inlet and outlet can be positive pressure or negative pressure. Summary of the invention

[0005] The main purpose of the present application is to provide a positive and negative pressure dual-purpose reversing valve with a pressure-maintaining function, wherein the positive and negative pressure dual-purpose reversing valve with a pressure-maintaining function comprises a valve body assembly, a valve stem, two pistons, two electromagnetic assemblies and a first spring, the valve body assembly has a first air inlet, a second air inlet, a flow channel, an air outlet, two sliding chambers, two piston chambers, two external air chambers, two external air channels and a third air inlet, one side of the flow channel is respectively connected to the first air inlet and the second air inlet, and the other side of the flow channel is connected to the air outlet, The two ends of the circulation channel are respectively communicated with the two sliding chambers, and one end of each sliding chamber away from the circulation channel is connected to a piston chamber, and the other end of each piston chamber is respectively communicated with the corresponding external air chamber, one end of each external air channel is respectively communicated with the corresponding external air chamber, and the other end of each external air channel is communicated with the third air inlet. The valve stem is slidably provided with the two sliding chambers and the circulation channel, and the two ends of the valve stem extend into the two piston chambers by a predetermined distance, respectively. The valve stem divides the circulation channel into a first air inlet chamber, a second air inlet chamber and an intermediate chamber, the first air inlet is communicated with the first air inlet chamber, the second air inlet is communicated with the second air inlet chamber, the intermediate chamber is located between the first air inlet chamber and the second air inlet chamber, and the air outlet is communicated with the intermediate chamber. A piston is slidably arranged in each piston chamber, and each electromagnetic assembly includes a coil frame and an iron core, the iron core is slidably arranged on the coil frame, and a coil is wound on the coil frame. A piston is abutted at the connection between each external air chamber and the external air channel. The iron core closes the connection between the outer air cavity and the outer air channel. When the coil is energized, the outer air cavity is connected to the outer air channel. One end of the first spring is connected to the valve body assembly, and the other end of the first spring is against the valve stem. When the first spring is in an undeformed state, the valve stem simultaneously blocks the connection between the first air inlet cavity, the second air inlet cavity and the middle cavity. Compared with the prior art, the present application has the advantages of isolating the two air inlets from the air outlet in a power-off state and the air source pressure at the air inlet and the air outlet can be positive pressure or negative pressure.

[0006] Another object of the present application is to provide a positive and negative pressure dual-purpose reversing valve with a pressure-maintaining function, wherein the positive and negative pressure dual-purpose reversing valve with a pressure-maintaining function also includes a closing plate, the closing plate is rotatably mounted on the valve body assembly and is arranged at the connection between the air outlet and the intermediate cavity, the end of the closing plate extending into the intermediate cavity has a half gear portion, and a side wall of the valve stem has a rack portion, the half gear portion is meshed with the rack portion, when the valve stem moves axially along the sliding cavity, the closing plate rotates a predetermined angle and opens the connection between the air outlet and the intermediate cavity, when the first spring is in an undeformed state, the closing plate closes the connection between the air outlet and the intermediate cavity, by providing the closing plate, when the sealing ring is worn, it can also play a role in following the valve stem and selectively closing the air outlet.

[0007] Another object of the present application is to provide a positive and negative pressure dual-purpose reversing valve with a pressure-maintaining function, wherein both ends of the rack portion are also provided with an anti-over-rotation portion. When the end face of one end of the valve stem abuts against a piston, and the other end of the piston abuts against the end face of the piston chamber away from the valve stem, the anti-over-rotation portion abuts against the edge of the closing plate. At the same time, the meshing teeth at one end of the rack portion abut against the meshing teeth at one end of the half-gear portion. The anti-over-rotation portion is provided to prevent the closing plate from swinging back and forth due to the action of the fluid.

[0008] In order to achieve at least one of the above-mentioned invention purposes, the present application provides a positive and negative pressure dual-purpose reversing valve with a pressure-maintaining function, wherein the positive and negative pressure dual-purpose reversing valve with a pressure-maintaining function comprises: A valve body assembly, the valve body assembly comprising a first air inlet, a second air inlet, a flow channel, an air outlet, two sliding chambers, two piston chambers, two external air chambers, two external air channels and a third air inlet, one side of the flow channel being respectively connected to the first air inlet and the second air inlet, the other side of the flow channel being connected to the air outlet, both ends of the flow channel being respectively connected to the two sliding chambers, one end of each sliding chamber away from the flow channel being connected to a piston chamber, and the other end of each piston chamber being respectively connected to the corresponding external air chamber, one end of each external air channel being respectively connected to the corresponding external air chamber, and the other end of each external air channel being connected to the third air inlet; and a valve stem, wherein the valve stem is slidably provided with the two sliding chambers and the flow channel, and the two ends of the valve stem extend into the two piston chambers by a predetermined distance respectively, the valve stem divides the flow channel into a first air inlet chamber, a second air inlet chamber and an intermediate chamber, the first air inlet port is communicated with the first air inlet chamber, the second air inlet port is communicated with the second air inlet chamber, the intermediate chamber is located between the first air inlet chamber and the second air inlet chamber, and the air outlet is communicated with the intermediate chamber; and Two pistons, each of which has a piston slidably disposed in a piston cavity; and two electromagnetic components, each of which includes a coil frame and an iron core, the iron core is slidably arranged on the coil frame, the coil is wound on the coil frame, each of which is in contact with a connecting portion between the outer air cavity and the outer air channel, and the connecting portion between the outer air cavity and the outer air channel is sealed, and when the coil is energized, the outer air cavity is connected to the outer air channel; and A first spring, one end of which is connected to the valve body assembly, and the other end of which is against the valve stem. When the first spring is in an undeformed state, the valve stem simultaneously blocks the communication between the first air inlet cavity, the second air inlet cavity and the intermediate cavity.

[0009] In one or more embodiments of the present application, the positive and negative pressure dual-purpose reversing valve with a pressure-maintaining function also includes a closing plate, which is rotatably mounted on the valve body assembly and is arranged at the connection between the air outlet and the intermediate cavity, and one end of the closing plate extending into the intermediate cavity has a half gear portion, and a side wall of the valve stem has a rack portion, and the half gear portion is meshed with the rack portion, and when the valve stem moves axially along the sliding cavity, the closing plate rotates a predetermined angle and opens the connection between the air outlet and the intermediate cavity, and when the first spring is in an undeformed state, the closing plate closes the connection between the air outlet and the intermediate cavity.

[0010] In one or more embodiments of the present application, both ends of the rack portion also have an anti-over-rotation portion. When the end face of one end of the valve stem abuts against the piston, and the other end of the piston abuts against the end face of the piston chamber away from the valve stem, the anti-over-rotation portion abuts against the edge of the closing plate, and at the same time, the meshing teeth at one end of the rack portion abut against the meshing teeth at one end of the semi-gear portion.

[0011] In one or more embodiments of the present application, the valve body combination has a shoulder combination, and the shoulder combination includes a first shoulder, a second shoulder, a third shoulder and a fourth shoulder. The first shoulder is located at the connection between the first air inlet chamber and one of the sliding chambers, the second shoulder is located at the connection between the first air inlet chamber and the middle chamber, the third shoulder is located at the connection between the second air inlet chamber and the middle chamber, and the fourth shoulder is located at the connection between the second air inlet chamber and the other sliding chamber. The valve stem has a plurality of annular grooves, each of which is sleeved with a sealing ring, and at least one sealing ring is fitted on the first shoulder, the second shoulder, the third shoulder and the fourth shoulder.

[0012] In one or more embodiments of the present application, one side of the valve stem has a first flow channel, a second flow channel, two transfer channels and two groups of connecting holes arranged in a circular array, the first flow channel is connected to the first air inlet cavity, the second flow channel is connected to the second air inlet cavity, one end of each of the transfer channels is respectively connected to a corresponding group of connecting holes, the other end of each of the transfer channels is respectively connected to the first flow channel or the second flow channel, one end of one group of connecting holes is connected to an annular groove facing the second shaft shoulder under normal conditions, and one end of the other group of connecting holes is connected to an annular groove facing the third shaft shoulder under normal conditions.

[0013] In one or more embodiments of the present application, the valve stem includes an intermediate piece and two extension pieces, both ends of the intermediate piece are respectively connected to the two extension pieces, the intermediate piece is slidably disposed in the circulation channel, the two extension pieces are respectively slidably disposed in the corresponding sliding cavity and extend into the corresponding piston cavity by a predetermined distance, and the intermediate piece is designed to be split along the center axis and then welded to each other.

[0014] In one or more embodiments of the present application, the valve body combination includes a first valve body, a second valve body, two third valve bodies and two fourth valve bodies, one end of the first valve body is connected to the second valve body, the opposite ends of the first valve body and the second valve body are each connected to the third valve body, the other end of each of the third valve bodies is connected to the fourth valve body, the first air inlet, the second air inlet, the flow channel, the air outlet and the sliding cavity are all arranged on the first valve body, each of the second valve bodies has an accommodating cavity for placing the first spring, each of the third valve bodies has a piston cavity and an outer air cavity, and each of the fourth valve bodies is provided with an electromagnetic component.

[0015] In the present invention, a positive and negative pressure dual-purpose reversing valve with a pressure-maintaining function comprises a valve body assembly, a valve stem, two pistons, two sets of coil frames and iron cores, and a first spring. The valve body assembly has a first air inlet, a second air inlet, a flow channel, an air outlet, two sliding cavities, two piston cavities, two external air cavities, two external air channels, and a third air inlet. The flow channel is respectively connected to the first air inlet, the second air inlet, the air outlet, and the two sliding cavities. Each sliding cavity is connected to a piston cavity, and the other end is connected to the external air cavity. The external air channel is connected to the external air cavity and the third air inlet. The valve stem is slidably provided with two sliding cavities and a flow channel, a piston is slidably provided in the piston cavity, an iron core is slidably provided on the coil frame, the iron core closes the connection between the external air cavity and the external air channel, when the coil is energized, the external air cavity is connected with the external air channel, the two ends of the first spring are abutted against the valve body combination and the valve stem, when the first spring is in an undeformed state, the valve stem simultaneously blocks the connection between the first air inlet, the second air inlet and the air outlet. Compared with the prior art, the present application has the advantages that the two air inlets are separated from the air outlet in the power-off state, and the air source pressure at the air inlet and the air outlet can be positive pressure or negative pressure. BRIEF DESCRIPTION OF THE DRAWINGS

[0016] These and / or other aspects and advantages of the present application will become clearer and easier to understand from the following detailed description of the embodiments of the present application in conjunction with the accompanying drawings, in which: Figure 1 The figure shows a structural schematic diagram of an existing two-inlet-one-outlet reversing valve; Figure 2 The figure shows a schematic diagram of the structure of an existing two-inlet-one-outlet reversing valve installed on a filling bottle body; Figure 3 The figure shows a cross-sectional view of a positive and negative pressure dual-purpose reversing valve with a pressure-maintaining function of the present application; Figure 4 The figure shows a structural schematic diagram of a positive and negative pressure dual-purpose reversing valve with a pressure-maintaining function of the present application; Figure 5 Picture shows Figure 3 A local enlarged view of point C; Figure 6 Picture shows Figure 3 A local enlarged view of D; Figure 7 Picture shows Figure 3 A local enlarged view of point E; Figure 8 The diagram shows the position of the closing piece when the valve stem moves to the limit position; Fig. 9 The diagram shows the schematic diagram of the sealing piece swinging under the action of the fluid when the valve stem moves to the limit position; Fig.10 The figure shows a schematic structural diagram of the sealing piece when the anti-over-rotation part is provided in the present application. DETAILED DESCRIPTION

[0017] The terms and words used in the following specification and claims are not limited to the literal meanings, but are merely used by the inventor to enable a clear and consistent understanding of the present application. Therefore, it will be apparent to those skilled in the art that the following description of various embodiments of the present application is provided for illustrative purposes only and not for the purpose of limiting the present application as defined by the appended claims and their equivalents.

[0018] It is to be understood that the term "one" should be understood as "at least one" or "one or more", that is, in one embodiment, the number of an element may be one, while in another embodiment, the number of the element may be multiple, and the term "one" should not be understood as a limitation on the quantity.

[0019] Although ordinals such as "first," "second," and the like will be used to describe various components, those components are not limited herein. The term is used only to distinguish one component from another. For example, a first component may be referred to as a second component, and likewise, a second component may be referred to as a first component without departing from the teachings of the inventive concept. The term "and / or" as used herein includes any and all combinations of one or more associated listed items.

[0020] The terms used herein are only used for the purpose of describing various embodiments and are not intended to be limiting. As used herein, singular forms are intended to also include plural forms, unless the context clearly indicates an exception. In addition, it will be understood that the terms "including" and / or "having" when used in this specification specify the presence of the described features, numbers, steps, operations, components, elements or combinations thereof, without excluding the presence or addition of one or more other features, numbers, steps, operations, components, elements or groups thereof.

[0021] Schematic diagram of a positive and negative pressure dual-purpose reversing valve with pressure-maintaining function. refer to Figures 3 to 10 According to a preferred embodiment of the present invention, a positive and negative pressure dual-purpose reversing valve with a pressure-maintaining function includes a valve body assembly 10, a valve stem 20, two pistons 30, two electromagnetic assemblies 40 and a first spring 50.

[0022] Specifically, Figures 3 to 7As shown, the valve body assembly 10 has a first air inlet 101, a second air inlet 102, a circulation channel 103, an air outlet 104, two sliding chambers 105, two piston chambers 106, two external air chambers 107, two external air channels 108 and a third air inlet 109, one side of the circulation channel 103 is respectively connected to the first air inlet 101 and the second air inlet 102, the other side of the circulation channel 103 is connected to the air outlet 104, both ends of the circulation channel 103 are respectively connected to the two sliding chambers 105, one end of each sliding chamber 105 away from the circulation channel 103 is connected to a piston chamber 106, and the other end of each piston chamber 106 is respectively connected to the corresponding external air chamber 107, one end of each external air channel 108 is respectively connected to the corresponding external air chamber 107, and the other end of the external air channel 108 is connected to the third air inlet 109.

[0023] In addition, if Figure 5 and Figure 6 As shown, the valve stem 20 is slidably penetrated by the two sliding chambers 105 and the circulation channel 103, and the two ends of the valve stem 20 extend into the two piston chambers 106 by a predetermined distance respectively, and the valve stem 20 divides the circulation channel 103 into a first air inlet chamber 1031, a second air inlet chamber 1032 and an intermediate chamber 1033, the first air inlet port 101 is connected to the first air inlet chamber 1031, the second air inlet port 102 is connected to the second air inlet chamber 1032, the intermediate chamber 1033 is located between the first air inlet chamber 1031 and the second air inlet chamber 1032, and the air outlet 104 is connected to the intermediate chamber 1033.

[0024] In addition, if Figure 5 As shown, a piston 30 is slidably disposed in each piston cavity 106 .

[0025] In addition, if Figure 3 and Figure 5 As shown, each of the electromagnetic components 40 includes a coil frame 401 and an iron core 402, and the iron core 402 is slidably set on the coil frame 401. The coil 403 is wound on the coil frame 401. Each connection between the external air cavity 107 and the external air channel 108 is abutted by an iron core 402, and the connection between the external air cavity 107 and the external air channel 108 is closed. When the coil 403 is energized, the external air cavity 107 is connected with the external air channel 108.

[0026] In addition, if Figure 7As shown, one end of the first spring 50 is connected to the valve body assembly 10, and the other end of the first spring 50 is against the valve stem 20. When the first spring 50 is in an undeformed state, the valve stem 20 simultaneously blocks the communication between the first air inlet cavity 1031, the second air inlet cavity 1032 and the intermediate cavity 1033.

[0027] It should be noted that, when the coils 403 of the two electromagnetic components 40 are both de-energized, under the elastic force of the first spring 50, the valve stem 20 closes the connection between the first air inlet chamber 1031 and the middle chamber 1033, and the connection between the second air inlet chamber 1032 and the middle chamber 1033 under normal conditions, so as to achieve the isolation of the first air inlet 101, the second air inlet 102 and the air outlet 104 when the electromagnetic component 40 is de-energized. Assuming that the air outlet 104 is connected to an external gas-filled bottle, when the air pressure in the external gas-filled bottle reaches a predetermined air pressure value, the two electromagnetic components 40 can be de-energized, and the valve stem 20 will automatically reset to the initial state under the elastic force of the first spring 50, and achieve the first air inlet 101 and the second air inlet 102 can no longer fill the external gas-filled bottle with gas. Compared with the prior art, it has the advantages of isolating the two air inlets and the air outlet and stabilizing the pressure in the power-off state.

[0028] It should also be noted that when the positive and negative pressure dual-purpose reversing valve with a pressure-maintaining function is working, only one of the electromagnetic components 40 is energized at the same time. When the coil 403 of one of the electromagnetic components 40 is energized, the corresponding iron core 402 moves in a direction away from the external air channel 108 and no longer blocks the connection between the external air channel 108 and the external air cavity 107. It should also be supplemented that the third air inlet 109 has positive pressure gas filled into the third air inlet 109. At the same time, when the iron core 402 moves in a direction away from the external air channel 108, the space of the external air cavity 107 becomes larger and the air pressure becomes smaller, then the positive pressure gas flows into the external air cavity 107 along the external air channel 108, and flows along the external air cavity 107 and the piston cavity 106. The connecting hole exerts a thrust on the piston 30 in the piston chamber 106, and makes the piston 30 approach the valve stem 20. At a certain moment, the piston 30 contacts the valve stem 20, and as the piston 30 moves further, the valve stem 20 is driven to move axially toward the other electromagnetic component 40, and the valve stem 20 is made to close the connection between the first air inlet chamber 1031 or the second air inlet chamber 1032 and the middle chamber 1033, and at the same time, the connection between the second air inlet chamber 1032 or the first air inlet chamber 1031 and the middle chamber 1033 is opened, so that when the coil 403 of the electromagnetic component 40 is energized, the corresponding first air inlet port 101 or the second air inlet port 102 is connected to the air outlet 104.

[0029] It should also be noted that, since a certain force is required to push the valve stem 20, when the gas pressure in the piston chamber 106 is negative pressure, the piston 30 will be difficult to push; and the present application, by setting the third air inlet 109, realizes the separate design of the third air inlet 109 and the first air inlet 101 and the second air inlet 102 in the flow channel, so that the first air inlet 101, the second air inlet 102 and the air outlet 104 can all be negative pressure. Compared with the prior art, it has a wider range of application scenarios and has the advantage that the air source pressure at the air inlet and the air outlet can be positive pressure or negative pressure.

[0030] Furthermore, in order to achieve the sealing between the valve stem 20 and the valve body assembly 10, as Figure 6 As shown, the valve body assembly 10 has a shoulder assembly 60, and the shoulder assembly 60 includes a first shoulder 601, a second shoulder 602, a third shoulder 603 and a fourth shoulder 604. The first shoulder 601 is located at the connection between the first air inlet chamber 1031 and one of the sliding chambers 105, the second shoulder 602 is located at the connection between the first air inlet chamber 1031 and the middle chamber 1033, the third shoulder 603 is located at the connection between the second air inlet chamber 1032 and the middle chamber 1033, and the fourth shoulder 604 is located at the connection between the second air inlet chamber 1032 and another of the sliding chambers 105. The valve stem 20 has a plurality of annular grooves 201, each of the annular grooves 201 is sleeved with a sealing ring 202, and the first shoulder 601, the second shoulder 602, the third shoulder 603 and the fourth shoulder 604 are all fitted with at least one sealing ring 202.

[0031] However, when the sealing ring 202 at the second shoulder 602 or the third shoulder 603 is worn, when both electromagnetic components 40 lose power, the first air inlet 101 or the second air inlet 102 is connected to the middle cavity 1033 and the air outlet 104. At this time, the pressure maintaining function of the positive and negative pressure dual-purpose reversing valve with pressure maintaining function fails, and the air pressure stability in the bottle body connected to the air outlet 104 cannot be achieved.

[0032] In view of this, in the embodiments of the present application, Figure 6As shown, the positive and negative pressure dual-purpose reversing valve with pressure maintaining function also includes a closing piece 70, which is rotatably mounted on the valve body assembly 10 and is arranged at the connection between the air outlet 104 and the intermediate cavity 1033. The end of the closing piece 70 extending into the intermediate cavity 1033 has a half gear portion 701, and a side wall of the valve stem 20 has a rack portion 203. The half gear portion 701 is meshed with the rack portion 203. When the valve stem 20 moves axially along the sliding cavity 105, the closing piece 70 rotates by a predetermined angle and opens the connection between the air outlet 104 and the intermediate cavity 1033. When the first spring 50 is in an undeformed state, the closing piece 70 closes the connection between the air outlet 104 and the intermediate cavity 1033.

[0033] It should be noted that, since the half gear portion 701 and the rack portion 203 are meshed, when the half gear portion 701 and the rack portion 203 are not disengaged, the angle of the closing piece 70 is actually determined by the rack portion 203, and since the rack portion 203 is fixedly connected to the valve stem 20, the position movement of the valve stem 20 actually determines the angle of the closing piece 70. When the first spring 50 is in an undeformed state, the first air inlet 101 and the second air inlet 102 are both blocked from the middle cavity 1033, and the closing piece 70 is arranged in a horizontal state and closes the air outlet 104; when the valve stem 20 moves to an extreme position along the axis and connects the first air inlet 101 or the second air inlet 102 to the middle cavity 1033, the closing piece 70 is in a nearly vertical tilted state and opens the connection between the air outlet 104 and the middle cavity 1033. When both electromagnetic assemblies 40 lose power, the valve stem 20 simultaneously blocks the first air inlet 101 and the second air inlet 102 from the intermediate cavity 1033, and the sealing piece 70 simultaneously blocks the connection between the air outlet 104 and the intermediate cavity 1033. At this time, even if the sealing ring 202 at the second shoulder 602 or the third shoulder 603 is worn and leaks under normal conditions, the gas in the bottle body connected to the air outlet 104 is blocked by the sealing piece 70 and cannot be connected to the first air inlet 101 or the second air inlet 1033. The first air inlet 101 or the second air inlet 102 is exchanged with the air outlet 104, which has the advantage of leak-proof sealing compared to the prior art; it is obvious that one of the functions of the valve stem 20 is to move toward the other electromagnetic component 40 when the corresponding electromagnetic component 40 is energized and make the first air inlet 101 or the second air inlet 102 connected with the air outlet 104, and when both electromagnetic components 40 are de-energized, the first air inlet 101 and the second air inlet 102 are both separated from the air outlet 104; its second function is to enable the closing plate 70 to selectively close the connection between the intermediate cavity 1033 and the air outlet 104.

[0034] Further, refer to Figure 8 When the valve stem 20 moves and the first air inlet 101 is connected to the middle cavity 1033, and the second air inlet 102 is blocked from the middle cavity 1033, the sealing piece 70 is in the meshing action of the half gear part 701 and the rack part 203. Figure 8 However, when the external air source flows into the middle cavity 1033 along the first air inlet 101 and flows toward the air outlet 104, the external air source will exert a force on the sealing piece 70 and cause it to Figures 8 to 9 The closure plate 70 swings back and forth within an angle range and makes abnormal noises, thereby increasing the wear on the closure plate 70.

[0035] In view of this, in the embodiments of the present application, Fig.10 As shown, both ends of the rack portion 203 also have an anti-over-rotation portion 2031. When one end face of the valve stem 20 abuts against a piston 30, and the other end of the piston 30 abuts against an end face of the piston chamber 106 away from the valve stem 20, the anti-over-rotation portion 2031 abuts against the edge of the closing plate 70, and at the same time, the meshing teeth at one end of the rack portion 203 abut against the meshing teeth at one end of the half gear portion 701.

[0036] It should be noted that, by providing the anti-over-rotation portion 2031, when the valve stem 20 moves to the limit position, the closing piece 70 abuts against the anti-over-rotation portion 2031, thereby limiting the closing piece 70 from moving along the valve stem 20. Fig.10 The closing piece 70 is difficult to swing in the clockwise direction due to the meshing restriction of the rack portion 203. Fig.10 The counterclockwise rotation avoids the above technical problems.

[0037] Furthermore, in order to prevent the valve stem 20 from rotating during the axial movement, Figure 7 As shown, one end of the valve stem 20 has two guide grooves 204, and the valve body assembly 10 has two extension ends 605. Each of the guide grooves 204 has an extension end 605 extending therein, and the side walls of the extension ends 605 are in contact with the two side walls of the guide grooves 204. By setting the extension ends 605, the valve stem 20 is restricted from circumferential rotation and the half gear portion 701 and the rack portion 203 are disengaged.

[0038] Furthermore, if Figure 6As shown, one side of the valve stem 20 has a first flow channel 205, a second flow channel 206, two transfer channels 207 and two groups of connecting holes 208 arranged in a ring array, the first flow channel 205 is connected to the first air inlet chamber 1031, the second flow channel 206 is connected to the second air inlet chamber 1032, one end of each of the transfer channels 207 is respectively connected to a corresponding group of connecting holes 208, the other end of each of the transfer channels 207 is respectively connected to the first flow channel 205 or the second flow channel 206, one end of one group of connecting holes 208 is connected to an annular groove 201 that is normally opposite to the second shaft shoulder 602, and one end of the other group of connecting holes 208 is connected to an annular groove 201 that is normally opposite to the third shaft shoulder 603.

[0039] It should be noted that, since the first flow channel 205 is normally connected to the first air inlet 101, and the second flow channel 206 is normally connected to the second air inlet 102, when the first air inlet 101 and the second air inlet 102 are both isolated from the intermediate cavity 1033, the gas in the first air inlet 101 and the second air inlet 102 will flow into the first flow channel 205 and the second flow channel 206, and flow into the corresponding connecting hole 208 along the corresponding transfer channel 207, and exert a force on the sealing ring 202 tightly attached to the second shoulder 602 and the third shoulder 603, so that the sealing ring 202 is more It fits with the second shoulder 602 and the third shoulder 603; in addition, when the outer ring surface of the sealing ring 202 is worn to a predetermined size, the compressive deformation of the sealing ring 202 is reduced when it abuts against the second shoulder 602 or the third shoulder 603, and the gap between the sealing ring 202 and the bottom wall of the annular groove 201 is increased. At this time, the gas flowing into the space between the bottom wall of the annular groove 201 and the inner ring of the sealing ring 202 from the connecting hole 208 will exert a force on the sealing ring 202, and make its outer ring surface fit tightly against the second shoulder 602 or the third shoulder 603, thereby extending the actual service life of the sealing ring 202.

[0040] Furthermore, in order to facilitate processing to obtain the first flow channel 205, the second flow channel 206, the transfer channel 207 and the connecting hole 208, as Figure 6As shown, the valve stem 20 includes an intermediate piece 2091 and two extension pieces 2092, and the two ends of the intermediate piece 2091 are respectively connected to the two extension pieces 2092 by welding. The intermediate piece 2091 is slidably set in the circulation channel 103, and the two extension pieces 2092 are respectively slidably set in the corresponding sliding cavity 105 and extend into the corresponding piston cavity 106 by a predetermined distance. The intermediate piece 2091 is designed to be split along the central axis and then welded to each other, that is, the first flow channel 205, the second flow channel 206, and the transfer channel 207 are obtained by processing and then welded to each other.

[0041] Further, in the embodiments of the present application, Figure 3 and Figure 4 As shown, the valve body assembly 10 includes a first valve body 606, a second valve body 607, two third valve bodies 608 and two fourth valve bodies 609, one end of the first valve body 606 is connected to the second valve body 607, the opposite ends of the first valve body 606 and the second valve body 607 are connected to the third valve body 608, and the other end of each of the third valve bodies 608 is connected to the fourth valve body 609, the first air inlet 101, the second air inlet 102, the flow channel 103, the air outlet 104 and the sliding cavity 105 are all arranged on the first valve body 606, refer to Figure 7 Each of the second valve bodies 607 has a receiving cavity 6071 for placing the first spring 50, each of the third valve bodies 608 has a piston cavity 106 and an outer air cavity 107, and each of the fourth valve bodies 609 is provided with an electromagnetic component 40.

[0042] In summary, the positive and negative pressure dual-purpose reversing valve with pressure maintaining function based on the embodiment of the present application is explained, which provides isolation between the two air inlets and the air outlet in the power-off state, and the air source pressure at the air inlet and the air outlet can be positive pressure or negative pressure, with the advantage of leak-proof sealing.

[0043] It should be understood by those skilled in the art that the embodiments of the present invention described above and shown in the accompanying drawings are only examples and do not limit the present invention. The purpose of the present invention has been fully and effectively achieved. The functional and structural principles of the present invention have been demonstrated and explained in the embodiments, and the embodiments of the present invention may be deformed or modified in any way without departing from the principles.

Claims

1. A positive and negative pressure dual-purpose reversing valve with pressure-maintaining function, characterized in that: The positive and negative pressure dual-purpose reversing valve with pressure-maintaining function comprises A valve body assembly, the valve body assembly comprising a first air inlet, a second air inlet, a flow channel, an air outlet, two sliding chambers, two piston chambers, two external air chambers, two external air channels and a third air inlet, one side of the flow channel being respectively connected to the first air inlet and the second air inlet, the other side of the flow channel being connected to the air outlet, both ends of the flow channel being respectively connected to the two sliding chambers, one end of each sliding chamber away from the flow channel being connected to a piston chamber, and the other end of each piston chamber being respectively connected to the corresponding external air chamber, one end of each external air channel being respectively connected to the corresponding external air chamber, and the other end of each external air channel being connected to the third air inlet; and a valve stem, wherein the valve stem is slidably provided with the two sliding chambers and the flow channel, and the two ends of the valve stem extend into the two piston chambers by a predetermined distance respectively, the valve stem divides the flow channel into a first air inlet chamber, a second air inlet chamber and an intermediate chamber, the first air inlet port is communicated with the first air inlet chamber, the second air inlet port is communicated with the second air inlet chamber, the intermediate chamber is located between the first air inlet chamber and the second air inlet chamber, and the air outlet is communicated with the intermediate chamber; and Two pistons, each of which has a piston slidably disposed in a piston cavity; and two electromagnetic components, each of which includes a coil frame and an iron core, the iron core is slidably arranged on the coil frame, the coil is wound on the coil frame, each of which is in contact with a connecting portion between the outer air cavity and the outer air channel, and the connecting portion between the outer air cavity and the outer air channel is sealed, and when the coil is energized, the outer air cavity is connected to the outer air channel; and A first spring, one end of which is connected to the valve body assembly, and the other end of which is against the valve stem. When the first spring is in an undeformed state, the valve stem simultaneously blocks the communication between the first air inlet cavity, the second air inlet cavity and the intermediate cavity.

2. The positive and negative pressure dual-purpose reversing valve with pressure-maintaining function according to claim 1, characterized in that: The positive and negative pressure dual-purpose reversing valve with a pressure-maintaining function also includes a closing plate, which is rotatably mounted on the valve body assembly and is arranged at the connection between the air outlet and the intermediate cavity. The end of the closing plate extending into the intermediate cavity has a half gear portion, and a side wall of the valve stem has a rack portion, and the half gear portion is meshed with the rack portion. When the valve stem moves axially along the sliding cavity, the closing plate rotates by a predetermined angle and opens the connection between the air outlet and the intermediate cavity. When the first spring is in an undeformed state, the closing plate closes the connection between the air outlet and the intermediate cavity.

3. The positive and negative pressure dual-purpose reversing valve with pressure-maintaining function according to claim 2 is characterized in that: Both ends of the rack portion also have an anti-over-rotation portion. When one end face of the valve stem abuts against a piston, and the other end of the piston abuts against an end face of the piston chamber away from the valve stem, the anti-over-rotation portion abuts against the edge of the closing plate, and at the same time, the meshing teeth at one end of the rack portion abut against the meshing teeth at one end of the half gear portion.

4. The positive and negative pressure dual-purpose reversing valve with pressure-maintaining function according to claim 3 is characterized in that: The valve body assembly has a shoulder assembly, which includes a first shoulder, a second shoulder, a third shoulder and a fourth shoulder. The first shoulder is located at the connection between the first air inlet chamber and one of the sliding chambers, the second shoulder is located at the connection between the first air inlet chamber and the middle chamber, the third shoulder is located at the connection between the second air inlet chamber and the middle chamber, and the fourth shoulder is located at the connection between the second air inlet chamber and the other sliding chamber. The valve stem has a plurality of annular grooves, each of which is sleeved with a sealing ring, and at least one sealing ring is attached to the first shoulder, the second shoulder, the third shoulder and the fourth shoulder.

5. The positive and negative pressure dual-purpose reversing valve with pressure-maintaining function according to claim 4, characterized in that: One side of the valve stem has a first flow channel, a second flow channel, two transfer channels and two groups of connecting holes arranged in a circular array, the first flow channel is connected to the first air inlet cavity, the second flow channel is connected to the second air inlet cavity, one end of each of the transfer channels is connected to a corresponding group of connecting holes, the other end of each of the transfer channels is connected to the first flow channel or the second flow channel, one end of one group of connecting holes is connected to an annular groove facing the second shaft shoulder in a normal state, and one end of the other group of connecting holes is connected to an annular groove facing the third shaft shoulder in a normal state.

6. The positive and negative pressure dual-purpose reversing valve with pressure-maintaining function according to claim 5, characterized in that: The valve stem includes a middle piece and two extension pieces, both ends of the middle piece are connected to the two extension pieces respectively, the middle piece is slidably arranged in the flow channel, the two extension pieces are slidably arranged in the corresponding sliding cavity and extend into the corresponding piston cavity by a predetermined distance, and the middle piece is designed to be split along the central axis and then welded to each other.

7. The positive and negative pressure dual-purpose reversing valve with pressure-maintaining function according to any one of claims 1 to 6, characterized in that: The valve body combination includes a first valve body, a second valve body, two third valve bodies and two fourth valve bodies, one end of the first valve body is connected to the second valve body, the opposite ends of the first valve body and the second valve body are connected to the third valve body, the other end of each of the third valve bodies is connected to the fourth valve body, the first air inlet, the second air inlet, the flow channel, the air outlet and the sliding cavity are all arranged on the first valve body, each of the second valve bodies has an accommodating cavity for placing the first spring, each of the third valve bodies has a piston cavity and an outer air cavity, and each of the fourth valve bodies is provided with an electromagnetic component.

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