Pressure reducing valve

Abstract

The utility model provides a pressure reducing valve, and belongs to the technical field of valves. The problem that assembling is inconvenient is solved. The valve body is provided with an inlet and an outlet, the valve seat is positioned in the valve body in the vertical direction, the valve rod penetrates through the valve seat, a large leather film is fixed between the outer side of the upper end of the valve rod and the valve body, a small leather film is further fixed on the outer side of the middle of the valve rod, a pressure guiding channel is formed in the valve rod, one end of the pressure guiding channel is communicated with the inlet, and the valve seat is in a barrel shape with the upper end and the lower end open. An annular mounting seat is integrally and fixedly connected into the valve seat, an annular pressing piece is connected into the upper end of the valve seat in a threaded mode, the outer edge of the small leather film is fixed between the mounting seat and the lower end of the pressing piece, a plurality of medium passing openings are formed in the position, lower than the mounting seat, of the outer side of the valve seat in the circumferential direction, and the medium passing openings communicate with the outlet. The outer edge of the large leather film abuts against the upper end of the pressing piece, a pressure adjusting cavity is formed among the large leather film, the small leather film, the valve rod and the pressing piece, and the other end of the pressure guiding channel is communicated with the pressure adjusting cavity. The device has the advantages of convenience in assembly and the like.

Description

Technical Field

[0001] The utility model belongs to the technical field of valves and relates to a pressure reducing valve. Background Art

[0002] The pressure reducing valve is essentially a self-operated pressure differential control device. Its working principle is to reduce the inlet pressure to a certain required outlet pressure and rely on the energy of the medium itself to automatically maintain a stable outlet pressure. For example, a pressure reducing valve disclosed in patent application number 201911242590.8 includes a valve body and a valve core, a pressure-stabilizing spring is arranged between the valve body and the valve core, a valve cavity is arranged in the valve body, a valve seat is fixed in the valve cavity, a flow control port is arranged on the valve seat, the valve core includes a valve stem, a pressure regulating part arranged corresponding to the flow control port is fixed on the valve stem, a small diaphragm is fixed between the valve stem and the valve body, a low-pressure cavity is formed in the valve cavity between the valve seat and the small diaphragm, a high-pressure cavity is formed in the valve cavity on the other side of the valve seat, an air inlet connected to the high-pressure cavity and an air outlet connected to the low-pressure cavity are arranged on the valve body, a large diaphragm is also fixed between the valve stem and the valve body, the small diaphragm is located between the large diaphragm and the pressure regulating part, a pressure regulating cavity is formed between the small diaphragm and the large diaphragm in the valve cavity, and an air passage connecting the high-pressure cavity and the pressure regulating cavity is provided on the valve stem. During operation, gas enters the high-pressure chamber through the inlet, then passes through the flow control port in the valve seat into the low-pressure chamber before exiting through the outlet. The high-pressure chamber and the regulating chamber are connected via a vent channel in the valve stem, and the air pressure in the high-pressure chamber is the same as that in the regulating chamber. When the pressure reducing valve is ventilated, the valve core is subjected to the force of the regulating chamber's air pressure on the large diaphragm, the force of the low-pressure chamber's air pressure on the small diaphragm, and the force of the spring on the valve core. These forces act together to balance the forces on the valve core, thereby maintaining its stability. When the air pressure in the high-pressure chamber increases or decreases, the air pressure in the pressure-regulating chamber increases or decreases synchronously, causing the large diaphragm to drive the valve stem to move upward or downward. At the same time, the air pressure in the low-pressure chamber also increases or decreases, causing the small diaphragm to also drive the valve stem to move upward or downward. Under the joint action of the large diaphragm and the small diaphragm, the relative position of the pressure regulating component and the flow control port can be immediately changed, that is, the pressure reducing gap between the pressure regulating component and the valve seat changes, thereby immediately reducing or increasing the air pressure in the low-pressure chamber, so that the air pressure at the outlet is maintained within a certain air pressure range, thereby achieving the effect of pressure stabilization.

[0003] The outer edge of the small diaphragm is compressed by a locating member, which is fixed to the valve body by fasteners. The small diaphragm is smaller than the large diaphragm. This means that when the locating member is fixed to the valve body with fasteners to compress the small diaphragm, the large diaphragm cannot be installed on the valve stem first. In other words, the large diaphragm can only be installed on the valve stem after the small diaphragm is compressed (otherwise, the presence of the large diaphragm will inevitably hinder the fixing operation of the locating member in the valve body). Moreover, the valve seat is also fixed separately to the valve body. The valve seat is located between the small diaphragm and the sealing gasket at the lower end of the valve stem. Both the small diaphragm and the sealing gasket at the lower end of the valve stem are larger than the inner hole of the valve seat. This means that one of the small diaphragm and the sealing gasket must be installed on the valve stem after the valve seat is fixed to the valve body. As a result, the pressure reducing valve has a significant disadvantage in terms of assembly convenience. Utility Model Content

[0004] The purpose of the utility model is to solve the above problems in the prior art and propose a pressure reducing valve to solve the problem of inconvenient assembly.

[0005] The purpose of this utility model can be achieved through the following technical solutions:

[0006] The cam is secured to the upper edge of the valve body with an angular channel formed between the top and bottom of the valve body, with the cam being secured to the lower edge of the valve body with a channel formed between the top and bottom of the valve body.

[0007] During operation, the valve stem is in a state where there is a gap between its lower end and the bottom of the valve seat. Most of the medium entering from the inlet enters the valve seat through this gap and flows out to the outlet through the medium port on the side of the valve seat. A small amount of the medium at the inlet enters the pressure regulating chamber through the pressure guide channel. The pressure in the pressure regulating chamber is the same as the pressure at the inlet. When the medium pressure at the inlet increases, the pressure inside the valve seat also increases, causing the small diaphragm to deform upward. At the same time, the pressure in the pressure regulating chamber also increases, causing the large diaphragm to deform upward. The combined upward deformation of the large and small diaphragms causes the valve stem to move upward, thereby reducing the gap between the lower end of the valve stem and the bottom of the valve seat, so that the medium pressure at the outlet can be reduced to the set value.

[0008] This pressure reducing valve sets the valve seat as a cylinder with openings at both ends and an annular mounting seat integrally connected to the inner side thereof, and the outer edge of the small diaphragm is pressed against the mounting seat while being compressed by connecting a compression piece with the internal thread of the upper end of the valve seat, while the outer edge of the large diaphragm is pressed against the outer side of the upper end of the compression piece, and a pressure regulating chamber is directly formed between the large diaphragm, the small diaphragm, the compression piece and the valve stem, so that the large diaphragm, the small diaphragm, the valve stem and the compression piece constitute a module, which only needs to be assembled before being assembled with the valve body and then directly installed into the valve body, thereby eliminating the need to perform assembly operations on the components involved in the pressure regulating structure in the narrow space of the valve body, thereby greatly improving the convenience of assembly.

[0009] In the above-mentioned pressure reducing valve, the upper end of the clamping piece extends out of the valve seat, the valve body includes a main body and a valve cover threadedly connected to the upper end of the main body, an annular positioning seat 1 is provided near the upper end of the main body, and an annular positioning seat 2 is provided on the outer side of the upper end of the clamping piece. The positioning seat 1 and the positioning seat 2 cooperate to form an annular groove and the outer edge of the large membrane is embedded in the annular groove, and the lower end of the valve cover rests on the upper side of the outer edge of the large membrane.

[0010] An annular positioning seat 1 is provided in the body and an annular positioning seat 2 is provided on the outer side of the upper end of the clamping piece. The positioning seat 1 and the positioning seat 2 cooperate to form an annular groove. After the lower end of the valve cover is threadedly connected to the upper end of the valve body, the outer edge of the large diaphragm is fixed in the annular groove, thereby making the outer edge of the large diaphragm fixed to the valve body and the clamping piece at the same time, ensuring that there is no gap between the large diaphragm and the clamping piece, thereby ensuring the sealing of the pressure regulating chamber formed by the large diaphragm, small diaphragm, valve stem and clamping piece.

[0011] In the above-mentioned pressure reducing valve, the body further comprises an annular abutment seat, which is positioned below the first abutment seat. The upper end of the pressing member radially protrudes out of the valve seat and abuts against the first abutment seat.

[0012] During assembly, the module consisting of the valve stem, compression piece, valve seat, large diaphragm, and small diaphragm is placed into the valve body. The portion of the compression piece's upper end that radially protrudes from the valve seat rests against the abutment seat, and the outer edge of the large diaphragm rests against the positioning seat. The lower end of the valve cover is then threaded into the upper end of the valve body to compress and secure the outer edge of the large diaphragm. This not only secures the outer edge of the large diaphragm, but also vertically secures the compression piece between the abutment seat and the valve cover. The valve seat is also threadedly connected to the compression piece. Positioning the compression piece vertically also means that the valve seat is positioned vertically.

[0013] In the above-mentioned pressure reducing valve, a plurality of matching recesses are provided on the inner side of the upper end of the pressing member along the circumferential direction.

[0014] The arrangement of the matching recess enables the fitting to cooperate with a tool, thereby enabling the installer to more conveniently thread the pressing piece to the upper end of the main body.

[0015] In the above-mentioned pressure reducing valve, sealing rings are provided on the outer side of the upper end of the pressing member and the outer side of the lower end of the valve seat. The outer edges of the two sealing rings are pressed against the inner wall of the body to form a seal, and the medium port is located between the two sealing rings.

[0016] The medium port is located between the two sealing rings, which means that the medium flowing out of the valve seat through the medium port will not leak upward or downward, but will only flow toward the outlet.

[0017] In the above-mentioned pressure reducing valve, the valve stem includes a first connecting body and a second connecting body threadedly connected to the lower end of the first connecting body, and the inner edge of the small membrane is fixed between the first connecting body and the second connecting body.

[0018] Through the above arrangement, the small diaphragm can be fixed to the valve stem without the aid of other connecting parts.

[0019] In the above-mentioned pressure reducing valve, a connecting head is protruding from the lower end of the first connecting body, and the connecting head is threadedly connected to the upper end of the second connecting body. The upper end of the second connecting body has a second annular groove, and the inner edge of the small membrane is embedded in the second annular groove. The inner edge of the small membrane is clamped between the lower end of the first connecting body and the upper end of the second connecting body.

[0020] During assembly, the small diaphragm is placed against the upper end of the second connector with its inner edge embedded in the second annular groove. The connector head of the first connector is then threaded into the upper end of the second connector until the lower end of the first connector presses the inner edge of the small diaphragm against the upper end of the second connector. The second annular groove secures the inner edge of the small diaphragm to the valve stem while achieving a good seal between the two.

[0021] In the above-mentioned pressure reducing valve, the upper end of the first connecting body has a first annular groove, the inner edge of the large diaphragm is embedded in the first annular groove, and a fastening screw is threadedly connected at the center position of the upper end of the first connecting body, and the inner edge of the large diaphragm is clamped between the head of the fastening screw and the upper end of the first connecting body.

[0022] During assembly, the large diaphragm is positioned against the upper end of the first connector with its inner edge embedded in the first annular groove. A set screw is then threaded into the center of the upper end of the first connector until the head of the set screw presses the inner edge of the large diaphragm against the upper end of the first connector. This arrangement allows the large diaphragm to be easily installed and secured to the upper end of the valve stem.

[0023] In the above-mentioned pressure reducing valve, the valve stem also includes a third connecting body, which is threadedly connected to the lower end of the second connecting body. The upper end of the third connecting body has a third annular groove, and an annular sealing member is provided in the third annular groove. The lower end of the second connecting body abuts against the inner edge of the sealing member. The upward movement of the valve stem can cause the outer edge of the sealing member to abut against the bottom of the valve seat to form a seal.

[0024] Compared with the prior art, the present pressure reducing valve sets the valve seat as a cylinder with openings at both ends and an annular mounting seat integrally connected to the inner side thereof, and the outer edge of the small diaphragm is pressed against the mounting seat while being compressed by connecting a compression piece with an internal thread on the upper end of the valve seat, while the outer edge of the large diaphragm is pressed against the outer side of the upper end of the compression piece, and a pressure regulating chamber is directly formed between the large diaphragm, the small diaphragm, the compression piece and the valve stem. In this way, the large diaphragm, the small diaphragm, the valve stem and the compression piece constitute a module. Before assembling with the valve body, it is only necessary to assemble the module first and then directly install it into the valve body. As a result, there is no need to perform assembly operations on the components involved in the pressure regulating structure in the narrow space of the valve body, which greatly improves the convenience of assembly. BRIEF DESCRIPTION OF THE DRAWINGS

[0025] Figure 1 This is a cross-sectional view of the pressure reducing valve.

[0026] Figure 2 yes Figure 1 A partial enlarged view of point A in the middle.

[0027] Figure 3 It is a cross-sectional view between the valve stem and valve seat in this pressure reducing valve.

[0028] Figure 4 This is a schematic diagram of the connection between the valve stem and the valve seat in this pressure reducing valve.

[0029] In the figure, 1, valve body; 1a, main body; 1a1, inlet; 1a2, outlet; 1a3, positioning seat 1; 1a4, abutment seat; 1b, valve cover; 2, valve seat; 2a, mounting seat; 2b, medium port; 2c, sealing surface; 3, valve stem; 3a, pressure-guiding channel; 3b, first connecting body; 3b1, first annular groove; 3c, second connecting body; 3c1, second annular groove; 3d, third connecting body; 3d1, third annular groove; 4, large diaphragm; 5, small diaphragm; 6, pressing piece; 6a, positioning seat 2; 6b, matching recess; 7, pressure-regulating chamber; 8, pressure-stabilizing spring; 9, spring seat; 10, sealing ring; 11, fastening screw; 12, sealing piece. DETAILED DESCRIPTION

[0030] The following are specific embodiments of the present invention and the accompanying drawings to further describe the technical solution of the present invention, but the present invention is not limited to these embodiments.

[0031] like Figures 1-4 As shown, a pressure reducing valve comprises a valve body 1 having an inlet 1a1 and an outlet 1a2, a valve seat 2 positioned within the valve body 1, and the valve body 1 extending through the valve seat 2. A large diaphragm 4 is fixed between the outer side of the upper end of a valve stem 3 and the valve body 1, and a small diaphragm 5 is also fixed to the outer side of the middle portion of the valve stem 3. The valve seat 2 is cylindrical with openings at both ends. An annular mounting seat 2a is integrally fixed to the valve seat 2, and an annular pressing member 6 is internally threadedly connected to the upper end of the valve seat 2. The outer edge of the small diaphragm 5 is fixed between the mounting seat 2a and the lower end of the pressing member 6. The outer edge of the large diaphragm 4 abuts the upper end of the pressing member 6. A pressure regulating chamber 7 is formed between the large diaphragm 4, the small diaphragm 5, the valve stem 3, and the pressing member 6. The valve stem 3 has a pressure guiding channel 3a within it. One end of the pressure guiding channel 3a is connected to the inlet 1a1, and the other end of the pressure guiding channel 3a is connected to the pressure regulating chamber 7. Specifically, the valve body 1 comprises a main body 1a and a valve cover 1b, the lower end of which is threadedly connected to the upper end of the main body 1a. An annular positioning seat 1a3 is provided within the main body 1a near the upper end. The upper end of the pressing member 6 extends beyond the valve seat 2. An annular positioning seat 2a is provided on the outer side of the upper end of the pressing member 6. The positioning seat 1a3 and the positioning seat 2a cooperate to form an annular groove, and the outer edge of the large diaphragm 4 is embedded in the annular groove. The lower end of the valve cover 1b abuts against the upper side of the outer edge of the large diaphragm 4. A pressure-stabilizing spring 8 is also provided within the valve body 1. A spring seat 9 is internally threadedly connected to the upper end of the valve cover 1b. The lower end of the pressure-stabilizing spring 8 abuts against the upper end of the valve stem 3, and the upper end of the pressure-stabilizing spring 8 abuts against the bottom of the spring seat 9. In this embodiment, the body 1a also includes an abutment seat 1a4, which is located below the positioning seat 1a3. The upper end of the compression member 6 radially protrudes outside the valve seat 2, and the portion of the upper end of the compression member 6 that radially protrudes outside the valve seat 2 abuts against the abutment seat 1a4. Several media ports 2b are circumferentially provided on the outside of the valve seat 2, below the mounting seat 2a. These ports 2b are connected to the outlet 1a2. Seal rings 10 are provided on the outer side of the upper end of the compression member 6 and the outer side of the lower end of the valve seat 2. Both seal rings 10 abut against the inner wall of the body 1a to form a seal, with the media ports 2b located between the two seal rings 10. Several mating recesses 6b are circumferentially provided on the inner side of the upper end of the compression member 6.

[0032] Furthermore, if Figure 3As shown, the valve stem 3 includes a first connector 3b and a second connector 3c threadedly connected to the lower end of the first connector 3b. The outer edge of the small diaphragm 5 is fixed between the first and second connectors 3b and 3c. Specifically, a connector protrudes from the lower end of the first connector 3b and is threadedly connected to the upper end of the second connector 3c. The upper end of the second connector 3c has a second annular groove 3c1. The inner edge of the small diaphragm 5 is embedded in the second annular groove 3c1 and is clamped between the lower end of the first connector 3b and the upper end of the second connector 3c. The upper end of the first connector 3b has a first annular groove 3b1, and the inner edge of the large diaphragm 4 is embedded in the first annular groove 3b1. A fastening screw 11 is threadedly connected at the center of the upper end of the first connector 3b. The inner edge of the large diaphragm 4 is clamped between the head of the fastening screw 11 and the upper end of the first connector 3b. The valve stem 3 also includes a third connector 3d, which is threadedly connected to the lower end of the second connector 3c. The upper end of the third connector 3d defines a third annular groove 3d1, within which an annular seal 12 is located. The lower end of the second connector 3c abuts the inner edge of the seal 12. Upward movement of the valve stem 3 causes the outer edge of the seal 12 to abut against the bottom of the valve seat 2, forming a seal. In this embodiment, the seal 12 is an O-ring, and the bottom of the valve seat 2 has a tapered sealing surface 2c. The outer diameter of the O-ring lies between the maximum and minimum inner diameters of the sealing surface 2c.

[0033] During operation, the valve stem 3, under the elastic force of the pressure-stabilizing spring 8, maintains a gap between the seal 12 and the bottom of the valve seat 2. Most of the medium entering at inlet 1a1 enters the valve seat 2 through this gap and flows out through the media port 2b on the side of the valve seat 2 to outlet 1a2. A small portion of the medium at inlet 1a1 enters the pressure-regulating chamber 7 through the pressure-conducting channel 3a. The pressure within the pressure-regulating chamber 7 is the same as the pressure at inlet 1a1. When the medium pressure at inlet 1a1 increases, the pressure inside the valve seat 2 also increases, causing the small diaphragm 5 to deform upward. Simultaneously, the pressure within the pressure-regulating chamber 7 also increases, causing the large diaphragm 4 to deform upward. The combined upward deformation of the large and small diaphragms 4 and 5 causes the valve stem 3 to move upward, thereby reducing the gap between the seal 12 and the bottom of the valve seat 2 and reducing the medium pressure at outlet 1a2 to the set value.

[0034] This pressure reducing valve sets the valve seat 2 as a cylinder with openings at both ends and has an annular mounting seat 2a integrally fixed on its inner side. The outer edge of the small diaphragm 5 is pressed against the mounting seat 2a and is compressed by connecting the compression piece 6 with the internal thread of the upper end of the valve seat 2. The outer edge of the large diaphragm 4 is pressed against the outside of the upper end of the compression piece 6, and a pressure regulating chamber 7 is directly formed between the large diaphragm 4, the small diaphragm 5, the compression piece 6 and the valve stem 3. In this way, the large diaphragm 4, the small diaphragm 5, the valve stem 3 and the compression piece 6 constitute a module. Before assembling with the valve body 1, you only need to assemble the module first and then directly install it into the valve body 1. Thereby, there is no need to perform assembly operations on the components involved in the pressure regulating structure in the narrow space of the valve body 1, which greatly improves the convenience of assembly.

[0035] The specific embodiments described herein are merely illustrative of the spirit of the present invention. Persons skilled in the art may make various modifications, additions, or substitutions to the described specific embodiments without departing from the spirit of the present invention or exceeding the scope defined by the appended claims.

Claims

1. A pressure reducing valve, comprising a valve body (1) having an inlet (1a1) and an outlet (1a2), a valve seat (2) positioned in the valve body (1) along the vertical direction, and a valve stem (3) passing through the valve seat (2), wherein a large diaphragm (4) is fixed between the outer side of the upper end of the valve stem (3) and the valve body (1), and a small diaphragm (5) is also fixed on the outer side of the middle part of the valve stem (3), a pressure guide channel (3a) is provided in the valve stem (3), and one end of the pressure guide channel (3a) is communicated with the inlet (1a1), characterized in that: The valve seat (2) is cylindrical with openings at both ends. An annular mounting seat (2a) is integrally connected to the valve seat (2) and an annular pressing piece (6) is internally threadedly connected to the upper end of the valve seat (2). The outer edge of the small diaphragm (5) is fixed between the mounting seat (2a) and the lower end of the pressing piece (6). A plurality of medium ports (2b) are circumferentially provided on the outer side of the valve seat (2) at a position lower than the mounting seat (2a). The medium ports (2b) are connected to the outlet (1a2). The outer edge of the large diaphragm (4) abuts against the upper end of the pressing piece (6). A pressure regulating chamber (7) is formed between the large diaphragm (4), the small diaphragm (5), the valve stem (3) and the pressing piece (6). The other end of the pressure guide channel (3a) is connected to the pressure regulating chamber (7).

2. The pressure reducing valve according to claim 1, characterized in that The upper end of the clamping member (6) extends out of the valve seat (2), and the valve body (1) includes a main body (1a) and a valve cover (1b) threadedly connected to the upper end of the main body (1a). The main body (1a) has an annular positioning seat (1a3) near the upper end, and the outer side of the upper end of the clamping member (6) has an annular positioning seat (6a). The positioning seat (1a3) and the positioning seat (6a) cooperate to form an annular groove, and the outer edge of the large membrane (4) is embedded in the annular groove. The lower end of the valve cover (1b) rests on the upper side of the outer edge of the large membrane (4).

3. The pressure reducing valve according to claim 2, characterized in that The body (1a) also has an annular abutment seat (1a4) located below the positioning seat (1a3). The upper end of the pressing member (6) protrudes radially out of the valve seat (2) and abuts against the abutment seat (1a4).

4. The pressure reducing valve according to claim 2 or 3, characterized in that: The inner side of the upper end of the pressing piece (6) is provided with a plurality of matching recesses (6b) along the circumferential direction.

5. The pressure reducing valve according to claim 3, characterized in that The outer side of the upper end of the pressing member (6) and the outer side of the lower end of the valve seat (2) are both provided with sealing rings (10), the outer edges of the two sealing rings (10) are pressed against the inner wall of the body (1a) to form a seal, and the medium port (2b) is located between the two sealing rings (10).

6. The pressure reducing valve according to claim 1, 2 or 3, characterized in that: The valve stem (3) includes a first connector (3b) and a second connector (3c) threadedly connected to the lower end of the first connector (3b), and the inner edge of the small membrane (5) is fixed between the first connector (3b) and the second connector (3c).

7. The pressure reducing valve according to claim 6, characterized in that The lower end of the first connector (3b) is provided with a connector head which is threadedly connected to the upper end of the second connector (3c). The upper end of the second connector (3c) has a second annular groove (3c1). The inner edge of the small membrane (5) is embedded in the second annular groove (3c1). The inner edge of the small membrane (5) is clamped between the lower end of the first connector (3b) and the upper end of the second connector (3c).

8. The pressure reducing valve according to claim 7, characterized in that The upper end of the first connector (3b) has a first annular groove (3b1), the inner edge of the large membrane (4) is embedded in the first annular groove (3b1), and a fastening screw (11) is threadedly connected at the center position of the upper end of the first connector (3b), and the inner edge of the large membrane (4) is clamped between the head of the fastening screw (11) and the upper end of the first connector (3b).

9. The pressure reducing valve according to claim 8, characterized in that The valve stem (3) further includes a third connecting body (3d), which is threadedly connected to the lower end of the second connecting body (3c), and the upper end of the third connecting body (3d) has a third annular groove (3d1), and an annular sealing member (12) is provided in the third annular groove (3d1). The lower end of the second connecting body (3c) abuts against the inner edge of the sealing member (12), and the upward movement of the valve stem (3) can cause the outer edge of the sealing member (12) to abut against the bottom of the valve seat (2) to form a seal.

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