JP2008282192A - Pressure reducing valve - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a pressure reducing valve for setting a variable range of a secondary side fluid pressure due to the pressure fluctuation of fluid supplied to the primary side within a desired range. <P>SOLUTION: When a primary pressure is defined as P<SB>1</SB>, and a secondary pressure is defined as P<SB>2</SB>, and the area receiving a pressure from fluid in a pressure chamber 51 by a piston 35 is defined as A<SB>1</SB>, and the area receiving a pressure from fluid in a communication path 16 by a valve body 26 is defined as A<SB>2</SB>, and the area receiving a pressure from fluid in a primary side fluid passage by the valve body 26 is defined as A<SB>3</SB>, and the area of an external pressure reception face 34 of the valve body 26 is defined as A<SB>4</SB>, and the spring load of a load spring 45 is defined as F<SB>1</SB>, and a spring load of a valve spring 33 is defined as F<SB>2</SB>, following formula is established. In the formula, P<SB>1</SB>×(A<SB>3</SB>-A<SB>4</SB>) affects the secondary pressure P<SB>2</SB>depending on the primary pressure P<SB>1</SB>. Therefore, it is possible to obtain desired secondary pressure characteristics by controlling the factor. <P>COPYRIGHT: (C)2009,JPO&INPIT

Description

  The present invention relates to a pressure reducing valve that can set the fluctuation range of the fluid pressure on the secondary side caused by the pressure fluctuation of the fluid supplied to the primary side to a desired range.

  Japanese Patent Application Laid-Open No. 2003-104495 proposes a compact pressure reducing valve in which fluctuations in the pressure on the primary side having a gas cylinder do not affect the secondary side including the beverage container (see paragraph 0011 of the same publication). . This pressure reducing valve is a pressure reducing valve that controls the amount of gas supplied from the primary side circuit in order to maintain the pressure of the secondary side circuit at a predetermined pressure. The primary side cylinder (22) includes An open hole (36) penetrating the inside and the outside is formed, and the valve body (28) is slidably inserted into the open hole (36), and the valve body (28) is inserted into the primary side cylinder (22). It is configured to come into contact with an external atmosphere (see paragraph 0012 of the same publication).

  According to this pressure reducing valve, since the internal pressure of the primary cylinder (22) communicating with the gas supply source acts not only on the valve body (28) but also on the external atmosphere side, the primary acting on the valve body (28). Since the internal pressure of the side cylinder (22) and the differential internal pressure acting on the external atmosphere cancel each other, the pressure fluctuation of the primary side circuit from the gas supply source to the primary side cylinder (22) affects the secondary side. In other words, the dispenser (1, 50) can always extract the beverage contained in the beverage container (2) under stable conditions (see paragraph 0013 of the publication).

And in the pressure-reducing valve (20, 66) of the dispenser (1, 50), the portion (30) of the valve body (28) inserted into the opening hole (36) has a transverse area in the opening hole (36). By forming it so as to have the same value as the cross-sectional area of the communication passage (26), the internal pressure of the primary cylinder (22) acting on the valve body (28) and the differential internal pressure acting on the external atmosphere side can be surely offset. (See paragraph 0014 of the same publication). Therefore, when there is a difference between these two cross-sectional areas, it is understood that the aforementioned internal pressure and the differential internal pressure are not canceled out, and that the pressure fluctuation on the primary side affects the secondary side.
JP 2003-104495 A

  The applicant of the present application states that the pressure of the fluid supplied to the primary side of the fluid passage causes the valve body to be in close contact with the valve seat, and the pressure of the fluid supplied to the primary side of the fluid passage is the valve body. We proposed a pressure control valve characterized in that an external pressure receiving surface on which the pressure outside the fluid passage acts was formed on the valve body so that the forces that would cause the valve to separate from the valve seat would cancel each other out. Application No. 2005-319520). However, depending on the intended use of the pressure control valve, these two forces may not need to be strictly canceled out. For example, this pressure control valve is used as a pressure reducing valve attached to the discharge port of an air tank of an air compressor in order to supply compressed air to an air tool. In such a pressure reducing valve, when the fluid pressure on the primary side fluctuates, if the fluctuation range of the fluid pressure on the secondary side falls within a predetermined range, there is often no problem in driving the air tool.

  An object of the present invention is to provide a pressure reducing valve that can set a fluctuation range of a secondary-side fluid pressure caused by pressure fluctuation of a fluid supplied to a primary side within a desired range.

  The pressure reducing valve of the present invention is disposed on the primary side of the fluid passage, the fluid passage for guiding the fluid supplied to the primary side to the secondary side, the valve seat formed in the fluid passage, and A valve body that regulates the size of the cross-sectional area of the fluid passage in cooperation with the valve seat, a valve spring that regulates the seat pressure of the valve body and the valve seat, and a secondary side of the fluid passage And a valve body driving member that displaces the valve body with respect to the valve seat in accordance with a pressure fluctuation on the secondary side of the fluid passage, and a load that biases the valve body driving member toward the valve body A pressure reducing valve that decompresses the fluid supplied to the primary side of the fluid passage and discharges the fluid to the secondary side, wherein the valve is controlled by the pressure of the fluid supplied to the primary side of the fluid passage. In order to reduce the force with which the body is pressed against the valve seat, Forming an external pressure receiving surface on which the pressure of the portion acts, thereby restricting the fluctuation range of the fluid pressure on the secondary side caused by the pressure fluctuation of the fluid supplied to the primary side to a predetermined range. Features.

  The pressure reducing valve according to the present invention is further configured so that when the valve body comes into close contact with the valve seat, the fluctuation range of the secondary fluid pressure caused by the pressure fluctuation of the fluid supplied to the primary side. The area is defined by the difference between the area defined by the outer edge of the portion and the area of the external pressure receiving surface.

  The pressure reducing valve of the present invention further includes a secondary pressure setting mechanism for changing a spring load of the load spring.

  The pressure reducing valve of the present invention further includes a secondary pressure setting mechanism for changing a spring load of the load spring.

  The pressure reducing valve of the present invention provides a highly versatile pressure reducing valve because the fluctuation range of the fluid pressure on the secondary side caused by the pressure fluctuation of the fluid supplied to the primary side can be regulated within a predetermined range. can do.

  According to the pressure reducing valve of the present invention, when the valve is closed, the fluid pressure on the primary side causes the valve body to be affected by the difference between the area defined by the outer edge of the contact portion between the valve body and the valve seat and the area of the external pressure receiving surface of the valve body. Since the force to be relatively displaced with respect to the valve seat is controlled, the force in the valve opening direction or the valve closing direction that the valve body receives by the fluid pressure on the primary side can be set accurately. Therefore, the fluctuation range of the fluid pressure on the secondary side of the pressure reducing valve can be accurately set within a desired range.

  Further, the fluid pressure on the secondary side of the pressure reducing valve can be determined by the force in the valve opening direction or the valve closing direction received by the valve body by the fluid pressure on the primary side, and the spring load of the load spring and the valve spring. Of these forces, if the force that the valve body receives due to the fluid pressure on the primary side can be set accurately, setting of the spring load of the load spring and the valve spring becomes easy. Thereby, the fluctuation range of the fluid pressure on the secondary side of the pressure reducing valve can be set accurately and easily.

  Furthermore, in the pressure reducing valve of the present invention, the valve body and the valve body driving member can be separated, and the valve body and the valve body driving member can be configured to be displaceable separately from each other. Therefore, when the fluid pressure on the secondary side becomes higher than the preset secondary pressure fluctuation range, the valve body drive member is separated from the valve body and displaced alone to form the valve body drive member. If the relief passage formed is opened and the secondary fluid passage is communicated with the atmosphere, the safety in using the pressure reducing valve can be improved.

  Other features of the present invention will become apparent from the following description of embodiments, described with reference to the drawings.

  1 to 4 show a direct acting pressure reducing valve 1 according to a first embodiment of the present invention.

  As shown in FIGS. 1 and 2, the body of the pressure reducing valve 1 is assembled with a base member 2, a cylinder member 3, a valve body support member 4 and a load spring housing 5 as basic constituent members.

  A through hole 6 extending in the axial direction is formed in the center of the base member 2, and a primary port 7 connected to a fluid supply source (not shown) is formed on the side surface of the base member 2, and the fluid A secondary port 8 connected to a device or the like (not shown) opens. The primary side port 7 communicates with the through hole 6, and the secondary side port 8 communicates with a vertical hole 10 having an opening at the bottom surface of the recess 9 formed on the upper surface of the base member 2.

  A valve body support member 4 screwed into the through hole 6 is mounted on the lower surface of the base member 2, and the valve body support member 4 closes the opening at the lower end of the through hole 6. A valve element insertion hole 11 is formed along the axis of the valve element support member 4, and the axis of the valve element insertion hole 11 coincides with the axis of the through hole 6. Since the valve body support member 4 is screwed into the through hole 6, the valve body support member 4 can be relatively displaced in the axial direction with respect to the base member 2 by rotating the valve body support member 4. .

  The cylinder member 3 is fitted in the recess 9 formed on the upper surface of the base member 2. At this time, the projection 12 formed at the center of the bottom of the cylinder member 14 is fitted into the opening at the upper end of the through hole 6. Seal rings 13 and 14 are interposed between the base member 2 and the cylinder member 3, and the gap between the base member 2 and the cylinder member 3 is maintained in an airtight state. A cylinder portion 15 is formed on the inner surface of the cylinder member 3. The axis of the cylinder portion 15 coincides with the axis of the through hole 6. A communication hole 16 is formed along the axial center of the protrusion 12, and the communication hole 16 extends between the through hole 6 and the cylinder portion 15. The axial center of the communication hole 16 coincides with the axial center of the through hole 6. A through passage 17 is formed at the bottom of the cylinder portion 15, and the through passage 17 communicates with the vertical hole 10.

  A load spring housing 5 is fixed to the upper surface of the base member 2 by a plurality of bolts 18 and 19. The housing 5 is configured by a hollow body having an opening 20 on the lower surface thereof. A flange portion 21 is formed on the peripheral edge portion of the opening 20 of the housing 5. When the housing 5 is fixed to the base member 2 with the bolts 18 and 19, the lower surface of the flange portion 21 is engaged with the upper surface of the cylinder member 3, whereby the cylinder member 3 is fixed inside the recess 9 of the base member 2. A screw hole 22 is formed at the center of the ceiling 21 of the housing 5. The axis of the screw hole 22 coincides with the axis of the housing 5 and coincides with the axis of the communication hole 16 and the axis of the through hole 6. An air communication hole 25 that allows the internal space 24 of the housing 5 to communicate with the atmosphere is formed in the side surface portion 23 of the housing 5.

  As shown in FIG. 3, the valve body 26 is disposed in the through hole 6. The valve body 26 includes a valve head 27 and a valve support 28, and the valve head 27 is fixed to the valve support 28. The valve head 27 is made of a material suitable for the purpose of use of the pressure reducing valve, and can be seated on a valve seat 29 formed on the lower surface of the protrusion 12 of the cylinder member 3. The valve seat 29 is formed so as to protrude from the lower surface of the projection 12 toward the inside of the through passage 6, and extends in an annular shape so as to surround the opening on the through hole 6 side of the communication passage 16. A recess 30 is formed at the center of the upper surface of the valve head 27, and the valve head 27 is seated on the valve seat 29 at the outer periphery of the recess 30. The valve support portion 28 of the valve body 26 extends along the axis of the through hole 6. A sliding portion 31 is formed below the valve support portion 28, and the sliding portion 31 is slidably fitted into the valve body insertion hole 11 of the valve body support member 4. A seal ring 32 is attached to the peripheral surface of the sliding portion 31, and the gap between the sliding portion 31 and the valve body insertion hole 11 is kept airtight by the seal ring 32. A valve spring 33 is interposed between the valve support portion 28 of the valve body 26 and the valve body support member 4, and the valve head 27 is seated on the valve seat 29 by the elastic force of the valve spring 33. Always biased in the direction. A lower end surface 34 of the sliding portion 31 of the valve support portion 28 is exposed to the outside of the valve body support member 4 from the valve body insertion hole 11 and constitutes an external pressure receiving surface that receives atmospheric pressure.

  As shown in FIGS. 1 and 3, a piston 35 is slidably fitted into the cylinder portion 15 of the cylinder member 3. A seal ring 36 is attached to the peripheral surface of the piston 35, and the gap between the peripheral surface of the piston 35 and the cylinder portion 15 is maintained in an airtight state by the seal ring 36. A protrusion 38 is formed at the center of the front surface 37 of the piston 35, and the protrusion 38 extends to the valve head 27 of the valve body 26 through the communication hole 16 of the cylinder member 3. A relief passage 39 is formed in the piston 35. The relief passage 39 extends along the axial center of the piston 35 and opens to the front end surface 40 of the protrusion 38 and the back surface 41 of the piston 35. As shown in FIG. 1, a bolt 42 is screwed into a screw hole 22 formed in the ceiling portion 21 of the housing 5, and a tip end portion of the bolt 42 abuts a central portion of a spring receiver 43 accommodated in the housing 5. The spring receiver 43 is supported. A load spring 45 is interposed between the washer 44 mounted on the back surface 41 of the piston 35 and the spring receiver 43, and the piston 35 is always urged in the direction of the valve body 26 by the elastic force of the load spring 45. .

  As shown in FIGS. 1, 2, and 3, a pressure indicator plate 46 on which a set pressure usable by the pressure reducing valve 1 is described is fixed to the outer surface of the ceiling portion 21 of the housing 5 with a fixing screw 47. A set pressure in the range of 0.0 to 1.0 MPa is graduated every 0.1 MPa on the pressure indicator plate 46 in FIG. Further, the pressure indicating plate 46 in FIG. 4B is graduated with a set pressure in the range of 0.0 to 2.5 MPa every 0.25 MPa. A pressure setting knob 47 is disposed above the pressure indicating plate 46, and the pressure setting knob 47 is fixed to the bolt 42 by a fixing screw 49. For example, in the pressure reducing valve 1 equipped with the pressure indicator plate 46 of FIG. 4A, when the pressure setting knob 47 is rotated and the indication line 50 of the pressure setting knob 48 is adjusted to 0.4 MPa of the pressure indicator plate 46, As the pressure setting knob 47 rotates, the bolt 42 rotates, and the spring receiver 43 moves up and down inside the housing 5 to change the resilience of the load spring 45. Thereby, the set pressure of the pressure reducing valve 1 becomes 0.4 MPa, and the pressure of the fluid flowing out from the secondary side port 8 becomes 0.4 MPa. The same applies to other pressure values calibrated on the pressure indicating plate 46. The pressure value described on the pressure indicator plate 46 is a secondary-side reference value, and the secondary-side fluid pressure can fluctuate within a fluctuation range including this reference value. The fluctuation range of the fluid pressure on the secondary side is set for each pressure reducing valve.

  Hereinafter, a case where the indicating line 50 of the pressure setting knob 48 is set to 0.4 MPa of the pressure indicating plate 46 in the pressure reducing valve 1 equipped with the pressure indicating plate 46 of FIG. In this state, the piston 35 of the pressure reducing valve 1 is displaced in the direction of the valve body 26 by the elastic force of the load spring 45, and the protruding portion 38 of the piston 35 is engaged with the valve body 26. That is, the front end surface 40 of the protruding portion 38 of the piston 35 is in close contact with the bottom surface of the recess 30 formed in the valve head 27 of the valve body 26, and the valve body 26 is resisted against the elastic force of the valve spring 33. 3 is pushed downward. As a result, the valve head 27 is separated from the valve seat 29, the primary side port 7 communicates with the secondary side port 8 through the communication hole 16, and the relief passage 39 is closed by the valve head 27. Here, the primary side port 7 is connected to a fluid supply source (not shown) such as an air compressor, and the secondary side port 8 is connected to a fluid device (not shown) such as an air tool, When this fluid device is operated, the fluid that has flowed into the primary port 7 flows into the communication passage 16 through the gap between the valve head 27 and the valve seat 29, and then the front surface 37 of the piston 35 and the cylinder portion 15. Into the pressure chamber 51 defined by The fluid that has flowed into the pressure chamber 51 is supplied to the secondary port 8 through the through passage 17 and the vertical hole 10, and is used in the fluid device connected to the secondary port 8.

  When the fluid pressure in the pressure chamber 51 becomes 0.4 MPa, which is the set pressure, during use of such a fluid device or due to the stop and restart of the fluid device, the piston 35 is brought into the elasticity of the load spring 45. Accordingly, the valve head 27 is seated on the valve seat 29 as shown in FIG. As a result, the communication passage 16 is closed, and the increase of the fluid pressure in the pressure chamber 51 is stopped. When the fluid pressure at the secondary port 8 decreases, the piston 35 is displaced in the direction of the valve body 26 by the elastic force of the load spring 45, and the protruding portion 38 of the piston 35 moves the valve head 27 from the valve seat 29. The communication path 16 is communicated with the primary side port 7. Thereby, the fluid flows into the pressure chamber 51, and the fluid pressure in the pressure chamber 51 rises to the set pressure. By repeating this operation, the pressure reducing valve 1 keeps the fluid pressure in the secondary fluid passage extending from the valve seat 29 to the secondary port 8 within a fluctuation range including 0.4 MPa that is the current set pressure. And

  When the fluid pressure in the pressure chamber 51 becomes higher than a preset fluctuation range with the valve head 27 of the valve body 26 seated on the valve seat 29, the piston 35 is elastically released from the load spring 45. Retreating against the force, the front end surface 40 of the protrusion 38 of the piston 35 is separated from the valve head 27. As a result, the relief passage 39 is opened, the pressure chamber 51 is communicated with the atmospheric communication hole 25, and the fluid pressure in the pressure chamber 51 is lowered to the fluctuation range.

The fluid pressure in the secondary fluid passage extending from the valve seat 29 to the secondary port 8 (hereinafter referred to as secondary pressure) is the primary fluid passage extending from the primary port 7 to the valve seat 29. The fluid pressure (hereinafter referred to as primary pressure) varies. That, _P 1 the primary pressure, the secondary pressure _{P 2,} the pressure receiving of receiving the pressure receiving area of the pressure piston 35 receives from the fluid in the pressure chamber 51 _{A 1,} the valve body 26 from the fluid in the communication passage 16 The area is A ₂ , the pressure receiving area of the pressure received by the valve body 26 from the fluid in the primary fluid passage is A ₃ , the area of the lower end surface (external pressure receiving surface) 34 of the valve body 26 is A ₄ , and the spring of the load spring 45 The load is F ₁ and the spring load of the valve spring 33 is F ₂ . 3, the diameter of the piston 35 is D ₁ , the diameter of the communication passage 16 is D ₂ , the diameter of the outer periphery of the protruding portion 38 of the piston 35 is D ₃ , and the valve head 27 of the valve body 26 is The diameter of the outer edge of the contact portion when it is in close contact with the seat 29 is D ₄ , and the diameter of the lower end surface (external pressure receiving surface) 34 of the valve body 26 is D ₅ .

A ₁ is expressed by the following equation.

A ₂ is represented by the following formula.

A ₃ is expressed by the following equation.

A ₄ is represented by the following formula.

Secondary pressure P ₂ is expressed by the following equation.

From Equation 5, it can be seen that the factor that the secondary pressure P ₂ is influenced by the primary pressure P ₁ is a term of P ₁ × (A ₃ −A ₄ ) in Equation 5.

That is, in order for the secondary pressure P ₂ to be determined independently from the primary pressure P ₁ , the diameter of the outer edge of the contact portion when the valve head 27 of the valve body 26 is in close contact with the valve seat 29 is set to D ₄ , This is achieved by making the diameter D ₅ of the lower end surface (external pressure receiving surface) 34 of the body 26 equal.

Similarly, the diameter of the outer edge of the contact portion when the primary pressure P ₁ and the valve head 27 of the valve body 26 are in close contact with the valve seat 29 is D _4, and the lower end surface (external pressure receiving surface) 34 of the valve body 26. the diameter D ₅ of, according to equation 5, can be primary pressure P ₁ is accurately control the effect on the secondary pressure P _2, provides a pressure reducing valve 1 having a desired secondary pressure characteristics.

  Note that the seat pressure of the valve body 26 and the valve seat 29 can be set by rotating the valve body support member 4 with respect to the base member 2 and thereby changing the spring load of the valve spring 33.

  FIG. 5 shows a second embodiment of the pressure reducing valve of the present invention. The feature of the pressure reducing valve 100 of this embodiment is that the pressure setting knob 52 is changed in shape to reduce the size of the pressure reducing valve 100 and to form a cylinder portion 54 on the base member 53, thereby reducing the number of parts. It is in the plan. By changing the shape of the pressure setting knob 52, the pressure indicator plate 46 of the first embodiment is eliminated, and the scale described on the pressure indicator plate 46 is indicated on the outer surface of the load spring housing 55. Other configurations are the same as those of the pressure reducing valve 1 of the first embodiment. In FIG. 5, the same reference numerals as those used in FIGS. 1 to 4 indicate components that basically perform the same functions. .

  6 and 7 show a third embodiment of the pressure reducing valve of the present invention. The pressure reducing valve 200 of this embodiment is characterized by a pressure setting lever 57 using a cam 56 instead of a rotary pressure setting knob, and for the base member 2, the cylinder member 3 and the load spring of the first embodiment. This is in the point of using a container member 58 in which the housing 5 is integrated. Reference numeral 59 in the figure indicates the rotation axis of the pressure setting lever 57. By adopting such a configuration, the number of parts can be further reduced, and the assembly efficiency of the product is greatly increased. The other configuration is the same as that of the pressure reducing valve 1 of the first embodiment. In FIGS. 6 and 7, the same reference numerals as those used in FIGS. 1 to 4 basically perform the same function. Indicates an element.

It is a longitudinal cross-sectional view of the pressure-reduction valve of this invention. Example 1 It is a front view of the pressure reducing valve of FIG. Example 1 It is sectional drawing to which the principal part of FIG. 1 was expanded. Example 1 4A is a top view of the pressure reducing valve of FIG. 1, and FIG. 4B is a top view of a modification of the pressure reducing valve of FIG. It is a longitudinal cross-sectional view of the other Example of the pressure-reduction valve of this invention. (Example 2) It is a longitudinal cross-sectional view of further another embodiment of the pressure reducing valve of the present invention. (Example 3) It is a longitudinal cross-sectional view which shows the effect | action of the pressure reducing valve of FIG. (Example 3)

Explanation of symbols

4 Valve body support member 7 Primary side port 8 Secondary side port 16 Communication path 25 Atmospheric communication hole 26 Valve body 27 Valve head 28 Valve support member 29 Valve seat 33 Valve spring 34 Lower end surface of valve support member (external pressure receiving surface) )
35 Piston 39 Relief passage 42 Bolt 45 Load spring 48 Pressure setting knob 46 Pressure indicating plate 51 Pressure chamber

Claims (4)

  A fluid passage for guiding the fluid supplied to the primary side to the secondary side; a valve seat formed in the fluid passage; and a primary side of the fluid passage, and in cooperation with the valve seat A valve body that regulates the size of a cross-sectional area of the fluid passage, a valve spring that regulates a seat pressure of the valve body and the valve seat, and a fluid passage disposed on the secondary side of the fluid passage. A valve body driving member that displaces the valve body with respect to the valve seat in accordance with a pressure fluctuation on the secondary side of the valve, and a load spring that biases the valve body driving member toward the valve body, In the pressure reducing valve, the pressure supplied to the primary side of the fluid passage is decompressed and discharged to the secondary side, and the valve body is pressed against the valve seat by the pressure of the fluid supplied to the primary side of the fluid passage. The pressure outside the fluid passage acts on the valve body so as to reduce the generated force. A pressure reducing valve characterized in that an external pressure receiving surface is formed, thereby restricting a fluctuation range of the fluid pressure on the secondary side caused by pressure fluctuation of the fluid supplied to the primary side to a predetermined range. .   2. The pressure reducing valve according to claim 1, wherein a fluctuation range of the fluid pressure on the secondary side caused by a pressure fluctuation of the fluid supplied to the primary side is determined when the valve body is in close contact with the valve seat. The pressure reducing valve is regulated by a difference between an area defined by an outer edge of the contact portion and an area of the external pressure receiving surface.   3. The pressure reducing valve according to claim 1, wherein the pressure reducing valve further includes a secondary pressure setting mechanism that changes a spring load of the load spring. 4.   The pressure reducing valve according to any one of claims 1 to 3, wherein the pressure reducing valve further includes a seat pressure setting mechanism for changing a spring load of the valve spring. .

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