Valve

Abstract

The invention provides a device to be controlled which can be easily adjusted. A valve (V1) is provided with: a housing (60) having a high-pressure space (S2) into which a high-pressure fluid (Pd) flows, a back-pressure space (S3) into which a back-pressure fluid (Pb) flows, a low-pressure space (S1) into which a low-pressure fluid (Ps) flows, and a passage (68) provided between the high-pressure space (S2) and the back-pressure space (S3); and a valve body (61) having a high-pressure pressure-receiving surface (A1-B1) located in the high-pressure space (S2), a back-pressure pressure-receiving surface (A1-E) located in the back-pressure space (S3), and a low-pressure pressure-receiving surface (B1-E) located in the low-pressure space (S1), the valve body (61) controlling the degree of opening of the passage (68), in which the valve (V1) is provided with a communication passage (67) connecting the back-pressure space (S3) and the low-pressure space (S1).

Description

Technical Field

[0001] This invention relates to valves, such as valves for controlling pressure. Background Technology

[0002] As one of the compressors used in various industrial fields, there is the scroll compressor. This type of compressor not only has high compression efficiency but also low noise, so it is used in many aspects such as refrigeration cycles.

[0003] The scroll compressor is constructed as follows: it has a scroll compression mechanism and an eccentric mechanism, etc. The scroll compression mechanism consists of a fixed scroll disk with vortex-shaped vortex teeth and a movable scroll disk with vortex-shaped vortex teeth. The eccentric mechanism is mounted on a rotating shaft, causing the movable scroll disk to rotate eccentrically. By causing the movable scroll disk to slide relative to the fixed scroll disk in eccentric rotation, the fluid supplied as refrigerant from the low-pressure chamber on the outer diameter side of the two scroll disks is pressurized, and high-pressure refrigerant is ejected from the ejection hole formed in the center of the fixed scroll disk.

[0004] In this type of scroll compressor, when the pressure in the ejection chamber of the refrigerant compressed by the scroll compressor increases, a force acts in the direction that moves the movable scroll away from the fixed scroll.

[0005] Patent Document 1 describes a scroll compressor with a back pressure communication passage connecting the ejection chamber to a back pressure chamber formed on the back side of the movable scroll plate. A throttling orifice is provided in the back pressure communication passage. A portion of the compressed refrigerant in the ejection chamber is depressurized and supplied to the back pressure chamber through the throttling orifice, pressing the movable scroll plate toward the fixed scroll plate, thus preventing the movable scroll plate from moving away from the fixed scroll plate.

[0006] Furthermore, the scroll compressor is equipped with a pressure relief port connecting the back pressure chamber and the suction chamber. A pressure regulating valve is located at the pressure relief port to adjust the pressure by releasing pressure from the back pressure chamber to the low pressure chamber. When the force pushing the valve core in the opening direction based on the back pressure chamber pressure exceeds the force pushing the valve core in the closing direction based on the low pressure chamber pressure and the spring force, the pressure regulating valve becomes open, allowing refrigerant from the back pressure chamber to flow to the low pressure chamber, thus reducing the pressure in the back pressure chamber. This prevents the movable scroll from being excessively pressed against the fixed scroll due to increased back pressure chamber pressure, thereby hindering the smooth operation of the movable scroll.

[0007] Existing technical documents

[0008] Patent documents

[0009] Patent Document 1: International Publication No. 2022 / 009769 (pages 8 and 9) Figure 1 ) Summary of the Invention

[0010] The problem that the invention aims to solve

[0011] In the scroll compressor described in Patent Document 1, when making adjustments to correspond to specifications, it is necessary to perform machining on the scroll compressor side, such as remapping the back pressure connection path and pressure relief hole, replacing the throttling hole set in the back pressure connection path, and replacing the spring constituting the pressure regulating valve, thus making the operation complicated.

[0012] This invention was made in view of such a problem, and its purpose is to provide a valve that enables easy adjustment of the controlled device.

[0013] Methods for solving problems

[0014] To address the aforementioned issues, the valve of the present invention comprises: a housing having a high-pressure space for the inflow of high-pressure fluid, a back-pressure space for the inflow of back-pressure fluid, a low-pressure space for the inflow of low-pressure fluid, and a passage disposed between the high-pressure space and the back-pressure space; and a valve core having a high-pressure receiving surface located in the high-pressure space, a back-pressure receiving surface located in the back-pressure space, and a low-pressure receiving surface located in the low-pressure space, the valve core controlling the opening degree of the passage, wherein the valve is provided with a connecting passage connecting the back-pressure space and the low-pressure space.

[0015] Therefore, the valve is equipped with a connection path that connects the back pressure space and the low pressure space, so that the controlled equipment can be easily adjusted without processing the controlled equipment side.

[0016] Alternatively, the connecting path can be a passageway that runs through the valve core.

[0017] Therefore, it is possible to form a connecting path without processing the controlled equipment.

[0018] Alternatively, the connecting path can be a passageway that runs through the housing.

[0019] Therefore, it is possible to form a connecting path without processing the controlled equipment.

[0020] Alternatively, the back pressure space and the low pressure space can be configured adjacent to each other, and the connecting passage can be arranged between the housing and the valve core.

[0021] Therefore, it is possible to easily construct a connecting path without modifying the controlled equipment.

[0022] Alternatively, the connecting path can be the radial gap between the housing and the valve core, which is always connected to the back pressure space and the low pressure space.

[0023] Therefore, it is possible to easily construct a connecting circuit without processing the housing or valve core.

[0024] To address the aforementioned issues, the valve of the present invention comprises: a housing having a high-pressure space for the inflow of high-pressure fluid, a back-pressure space for the inflow of back-pressure fluid, a low-pressure space for the inflow of low-pressure fluid, and a passage disposed between the back-pressure space and the low-pressure space; and a valve core having a high-pressure receiving surface located in the high-pressure space, a back-pressure receiving surface located in the back-pressure space, and a low-pressure receiving surface located in the low-pressure space, the valve core controlling the opening degree of the passage, wherein the valve is provided with a connecting passage connecting the high-pressure space and the back-pressure space.

[0025] Therefore, the valve is equipped with a connection path that connects the high-pressure space and the back-pressure space, so that the controlled equipment can be easily adjusted without processing the controlled equipment side.

[0026] Alternatively, the connecting path can be a passageway that runs through the housing.

[0027] Therefore, it is possible to form a connecting path without processing the controlled equipment.

[0028] Alternatively, the connecting path can be a passageway that runs through the valve core.

[0029] Therefore, it is possible to form a connecting path without processing the controlled equipment.

[0030] Alternatively, the high-pressure space and the back-pressure space can be configured adjacent to each other, and the connecting passage can be arranged between the housing and the valve core.

[0031] Therefore, it is possible to easily construct a connecting path without modifying the controlled equipment.

[0032] Alternatively, the connecting path can be the radial gap between the housing and the valve core, which is always connected to the high-pressure space and the back-pressure space.

[0033] Therefore, it is possible to easily construct a connecting circuit without processing the housing or valve core. Attached Figure Description

[0034] Figure 1 This is a schematic structural diagram of a scroll compressor that uses the valve of Embodiment 1 of the present invention.

[0035] Figure 2 This is a cross-sectional view of the valve in Embodiment 1 of the present invention.

[0036] Figure 3 This is a cross-sectional view of the valve in the normally closed state in Example 1.

[0037] Figure 4 This is a cross-sectional view of a modified example 1-1 of the valve in Example 1.

[0038] Figure 5This is a cross-sectional view of the valve in Embodiment 2 of the present invention.

[0039] Figure 6 This is a cross-sectional view of a modified example 2-1 of the valve in Example 2.

[0040] Figure 7 This is a cross-sectional view of a modified example 2-2 of the valve in Example 2.

[0041] Figure 8 This is a cross-sectional view of the valve in Embodiment 3 of the present invention.

[0042] Figure 9 This is a cross-sectional view of a variation of the valve in Example 3-1.

[0043] Figure 10 This is a cross-sectional view of a variation of the valve in Example 3-2.

[0044] Figure 11 This is a cross-sectional view of the valve in Embodiment 4 of the present invention.

[0045] Figure 12 This is a cross-sectional view of the valve in Example 4 after the valve core moves due to the pressure difference, showing the closed valve state.

[0046] Figure 13 This is a cross-sectional view of a variation of the valve in Example 4, 4-1.

[0047] Figure 14 This is a cross-sectional view of a variation of the valve in Example 4, Example 4-2.

[0048] Figure 15 This is a cross-sectional view of the valve in Embodiment 5 of the present invention.

[0049] Figure 16 This is a cross-sectional view of a variation of the valve in Example 5-1.

[0050] Figure 17 This is a cross-sectional view of the valve in Embodiment 6 of the present invention.

[0051] Figure 18 This is a cross-sectional view of a variation of the valve in Example 6-1.

[0052] Figure 19 This is a cross-sectional view of a variation of the valve in Example 6-2. Detailed Implementation

[0053] Hereinafter, the manner in which the valve is used to implement the present invention will be described based on embodiments.

[0054] Example 1

[0055] Reference Figures 1-4The valve of Example 1 will be described. The valve of the present invention is applied to a scroll compressor C used in an air conditioning system of rotating machinery including an eccentric mechanism, such as an automobile. This scroll compressor C draws in, compresses, and ejects a refrigerant as a fluid. Furthermore, in this embodiment, the refrigerant is a gas, in a state mixed with a mist of lubricating oil.

[0056] First, let's explain the scroll compressor C. For example... Figure 1 As shown, the scroll compressor C mainly consists of a housing 1, a rotating shaft 2, an inner housing 3, a scroll compression mechanism 4, a side seal 7, a thrust plate 8, and a drive motor M.

[0057] The housing 1 consists of a cylindrical outer shell 11 and a cover 12 that closes the opening of the outer shell 11. The opening of the outer shell 11, which is on the opposite side in the axial direction to the opening closed by the cover 12, is closed by a drive motor M.

[0058] Inside the outer casing 11 are formed: a low-pressure chamber 20, which receives low-pressure refrigerant (Ps) via a refrigerant circuit (not shown) through the suction port 10; a high-pressure chamber 30, which receives high-pressure refrigerant (Pd) compressed by the scroll compressor 4; and a back-pressure chamber 50, which receives lubricating oil and a portion of the refrigerant compressed by the scroll compressor 4 (Pb) via a back-pressure control valve V1. The back-pressure chamber 50 is formed inside a cylindrical inner casing 3 housed within the outer casing 11.

[0059] The cover 12 has an ejection passage 13 that connects a refrigerant circuit (not shown) to the high-pressure chamber 30. Furthermore, the cover 12 has a branch from the ejection passage 13 that forms a portion of a back-pressure passage 14 that connects the high-pressure chamber 30 to the back-pressure chamber 50. Additionally, an oil separator 6 is provided on the ejection passage 13 to separate lubricating oil from the refrigerant.

[0060] The inner shell 3 is fixed in such a state that its axial end abuts against the end plate 41a of the fixed scroll disk 41 constituting the scroll compressor mechanism 4. Furthermore, a radially penetrating suction passage 15 is formed on the side wall of the inner shell 3. That is, the low-pressure chamber 20 is formed from the outside of the inner shell 3 into the interior of the inner shell 3 via the suction passage 15. The suction fluid Ps supplied to the interior of the inner shell 3 via the suction passage 15 is drawn into the scroll compressor mechanism 4.

[0061] The vortex compression mechanism 4 mainly consists of a fixed vortex disk 41 that is fixed in a sealed manner relative to the cover 12 and a movable vortex disk 42 housed inside the inner shell 3.

[0062] The fixed scroll plate 41 is made of metal and has vortex-shaped vortex teeth 41b. These vortex-shaped vortex teeth 41b protrude from the surface of the circular end plate 41a, i.e., the end face of the end plate 41a opposite to the movable scroll plate 42, toward the movable scroll plate 42. Furthermore, the fixed scroll plate 41 has a recess 41c formed on the inner diameter side of the back side of the end plate 41a, i.e., the end face of the end plate 41a that abuts against the cover 12. This recess 41c and the cover 12 divide the high-pressure chamber 30.

[0063] The movable scroll plate 42 is made of metal and has vortex-shaped vortex teeth 42b, which protrude from the surface of the circular end plate 42a, i.e., the end face of the end plate 42a opposite to the fixed scroll plate 41, toward the fixed scroll plate 41. Furthermore, the movable scroll plate 42 has a boss 42c protruding from the center of the back surface of the end plate 42a. The eccentric portion 2a formed on the rotating shaft 2 is rotatably inserted into the boss 42c. In this embodiment, the eccentric portion 2a of the rotating shaft 2 and the counterweight portion 2b protruding from the rotating shaft 2 in the outer diameter direction constitute an eccentric mechanism that causes the rotating shaft 2 to rotate eccentrically.

[0064] When the rotating shaft 2 is driven to rotate by the drive motor M, the eccentric part 2a rotates eccentrically, and the movable scroll plate 42 slides relative to the fixed scroll plate 41 while maintaining its posture. At this time, the movable scroll plate 42 rotates eccentrically relative to the fixed scroll plate 41. With this rotation, the contact position of the scroll teeth 41b and 42b moves sequentially in the direction of rotation, and the compression chamber 40 formed between the scroll teeth 41b and 42b gradually shrinks while moving towards the center. As a result, the suction fluid Ps drawn into the compression chamber 40 from the low-pressure chamber 20 formed on the outer diameter side of the scroll compression mechanism 4 is gradually compressed and finally ejected as high-pressure ejected fluid Pd into the high-pressure chamber 30 through the ejection hole 41d provided in the center of the fixed scroll plate 41.

[0065] The side seal 7 is made of resin, has a rectangular cross-section and appears annular when viewed axially, and is fixed to the back of the end plate 42a of the movable scroll plate 42. The side seal 7 has a sliding surface 7a that abuts against the sliding surface 8a formed on the thrust plate 8.

[0066] The thrust plate 8 is made of metal and is annular in shape, with a sealing ring 43 fixed thereon. The sealing ring 43 abuts against the inner circumferential end face of the inner shell 3. Thus, the thrust plate 8 functions as a thrust bearing, bearing the axial load of the movable scroll plate 42 via the side seal 7.

[0067] Furthermore, the side seal 7 and the sealing ring 43 divide the interior of the inner shell 3 into a low-pressure chamber 20 formed on the outer diameter side of the movable scroll plate 42 and a back-pressure chamber 50 formed on the back side of the movable scroll plate 42. The back-pressure chamber 50 is sealed with the rotating shaft 2 that penetrates and is inserted into the through hole 3a by the sealing ring 44, thereby forming a sealed space, wherein the sealing ring 44 is fixed to the inner circumference of the through hole 3a provided in the center of the inner shell 3.

[0068] Furthermore, a back pressure control valve V1, which serves as a valve, is provided on the back pressure communication path 14, which is formed by covering the cover 12, the fixed scroll plate 41, and the inner shell 3 and connects the high pressure chamber 30 and the back pressure chamber 50. In other words, the back pressure control valve V1 is provided inside the shell 1, which is isolated from the external gas.

[0069] A portion of the ejected fluid Pd, which is supplied to the high-pressure chamber 30 of the back pressure control valve V1 along with the lubricating oil separated by the oil separator 6, is pressurized to become the control fluid Pb and supplied to the back pressure chamber 50.

[0070] Furthermore, the inner shell 3 is formed with a pressure relief port 16 that connects the back pressure control valve V1 to the low pressure chamber 20.

[0071] Next, use Figure 2 , Figure 3 The back pressure control valve V1, which serves as a valve in this embodiment, will be described below. Figure 2 The left and right sides when viewed from the front are described as the left and right sides of the back pressure control valve V1.

[0072] like Figure 2 , Figure 3 As shown, the back pressure control valve V1 in this embodiment 1 is normally closed and mainly consists of a housing 60, a valve core 61, and a helical spring 62 that applies force to the valve core 61 in the sitting direction, i.e., the closing direction.

[0073] The housing 60 has a low-pressure space S1 communicating with the low-pressure chamber 20, a high-pressure space S2 communicating with the high-pressure chamber 30, and a back-pressure space S3 communicating with the back-pressure chamber 50. Furthermore, the housing 60 only needs to be divided into at least a portion of the low-pressure space S1, the high-pressure space S2, and the back-pressure space S3.

[0074] The housing 60 is cylindrical. A dividing wall portion 63e extending toward the inner diameter is formed on the left side of the axial center of the housing 60. A valve hole 63a extending axially is formed in the radial center of the dividing wall portion 63e.

[0075] Furthermore, a tapered surface is formed on the inner diameter side of the dividing wall portion 63e, which expands the diameter of the valve orifice 63a to the left. This tapered surface is the valve seat 65 that contacts and separates from the tapered surface 66 of the large-diameter main body portion 61a of the valve core 61. That is, the valve seat 65 and the tapered surface 66 constitute a valve 70 that controls the opening and closing of the flow path 68 between the valve seat 65 and the tapered surface 66 through contact and separation. Moreover, the opening degree of the flow path 68 is variable, and the flow rate passing through the flow path 68 can be adjusted. Hereinafter, the adjustment of the opening degree of the flow path 68 based on the movement of the valve core 61 will be described as the adjustment of the opening degree of the valve 70.

[0076] A dividing wall portion 63f extending toward the inner diameter is formed on the right side of the axial center portion of the housing 60. A through hole 63g is formed in the radial center portion of the dividing wall portion 63f.

[0077] A connecting hole 63d is formed at the axial center of the peripheral wall of the housing 60, which is radially through and communicates with the high-pressure chamber 30.

[0078] The space enclosed axially by the partitioned walls 63e and 63f is the high-pressure space S2. The high-pressure space S2 is connected to the high-pressure chamber 30 via the connecting hole 63d.

[0079] The low-pressure space S1 is recessed into the right end face of the housing 60 with an axial opening on the right side. The low-pressure space S1 is separated from the high-pressure space S2 by a dividing wall 63f.

[0080] A cover component 9 is screwed onto the inner circumferential surface of the opening at the left end of the housing 60. Furthermore, the cover component 9 can also be fixed to the housing 60 by various means other than screwing, but preferably, its axial position can be adjusted.

[0081] Multiple through holes 9a are formed on the cover component 9, which are axially extending and communicate with the back pressure chamber 50. A recess 9b with an opening on the right side is formed on the right end face of the cover component 9.

[0082] The space axially sandwiched between the cover component 9 and the housing 60 by the dividing wall 63e is the back pressure space S3. The back pressure space S3 is separated from the high pressure space S2 by the dividing wall 63e. The back pressure space S3 is connected to the back pressure chamber 50 via the through hole 9a.

[0083] The valve core 61 is formed as a stepped cylindrical shape having a large-diameter main body 61a and a small-diameter main body 61b.

[0084] The large-diameter main body 61a has a tapered surface 66 that narrows towards the right side of the axial direction. Furthermore, a recess 61c with an opening on the left side is formed on the left end face of the large-diameter main body 61a.

[0085] The large-diameter main body 61a is disposed in the back pressure space S3.

[0086] The smaller diameter main body portion 61b is formed as a cylinder extending axially to the right from the right end of the larger diameter main body portion 61a. The diameter of the smaller diameter main body portion 61b is approximately the same as the minimum outer diameter of the larger diameter main body portion 61a.

[0087] The small-diameter main body 61b is inserted through the valve hole 63a, the high-pressure space S2, the through hole 63g, and the low-pressure space S1.

[0088] The gap between the inner circumferential surface of the dividing wall portion 63f constituting the through hole 63g and the outer circumferential surface of the small-diameter main body portion 61b is extremely small, so the refrigerant hardly moves between the low-pressure space S1 and the high-pressure space S2 through this gap. Furthermore, the inner circumferential surface of the dividing wall portion 63f and the outer circumferential surface of the small-diameter main body portion 61b are smooth surfaces with the same diameter throughout the axial direction, and the two surfaces can slide relative to each other.

[0089] Furthermore, the valve core 61 has a straight connecting path 67 extending through the axis of the valve core 61.

[0090] The connecting passage 67 connects the back pressure space S3 and the low pressure space S1. In this embodiment, the flow path cross-section E of the connecting passage 67 is small. The connecting passage 67 functions as a throttling orifice, but it can also be a flow path cross-section that does not function as a throttling orifice. Furthermore, the connecting passage of the present invention can also be formed by embedding a fixed throttling orifice within a through hole with a relatively large flow path cross-section.

[0091] In addition, for ease of explanation, in Figure 2 , Figure 3 In the diagram, the connected path 67 is exaggerated. This is for... Figure 4 The same applies to the connected paths illustrated in subsequent diagrams. Furthermore, in Figure 2 , Figure 3 The range of the flow path section E is difficult to show in the diagram, so the label of the flow path section E is shown in parentheses next to the label of the connecting path 67 as (E). Figure 4 In all subsequent figures, the flow path cross-section of each connecting path is represented by flow path cross-section E, with the label of flow path cross-section E omitted.

[0092] In the valve core 61, the pressures of the control fluid Pb and the ejected fluid Pd act on the large-diameter main body 61a, while the pressure of the suction fluid Ps acts on the small-diameter main body 61b.

[0093] The effective pressure-bearing surface of the valve core 61, which acts as the back pressure-bearing surface, is approximately the same as the portion of the flow path section A1 of the valve seat 65 located on the outer side of the flow path section E of the connecting passage 67, where the conical surface 66 contacts the valve core 61 when it is seated on the valve seat 65. Hereinafter, the effective pressure-bearing surface of the valve core 61 acting on the pressure of the control fluid Pb will be referred to as "effective pressure-bearing surface (A1-E)".

[0094] The effective pressure-bearing surface of the valve core 61, which is the high-pressure pressure-bearing surface, acting on the pressure of the ejected fluid Pd, is approximately the same as the portion of the flow path section A1 of the valve seat 65 located on the outer side of the section B1, which is larger than the small-diameter main body portion 61b. Hereinafter, the effective pressure-bearing surface of the valve core 61 acting on the pressure of the ejected fluid Pd will be referred to as "effective pressure-bearing surface (A1-B1)".

[0095] The effective pressure-bearing surface of the valve core 61, which is the low-pressure pressure-bearing surface, is approximately the same as the portion of the cross section B1 of the small-diameter main body 61b located on the outer side compared to the flow path cross section E of the connecting passage 67. Hereinafter, the effective pressure-bearing surface of the valve core 61, which is the pressure of the suction fluid Ps, will be referred to as "effective pressure-bearing surface (B1-E)".

[0096] The helical spring 62 is a compression spring, configured such that its right end fits into the recess 61c of the valve core 61 and its left end fits into the recess 9b of the cover member 9. The force of the helical spring 62 can be adjusted by changing the position of the cover member 9 relative to the housing 60.

[0097] Next, the opening and closing operation of the back pressure control valve V1 will be explained. In the housing 60, the suction fluid Ps flows into the low-pressure space S1, the ejection fluid Pd flows into the high-pressure space S2, and the control fluid Pb flows into the back pressure space S3.

[0098] The force (F) generated by the pressure of the fluid Ps drawn into the valve core 61 acting on the effective pressure-bearing surface (B1-E) Ps1 =Ps×(B1-E)) and the force (F) generated by the pressure of the ejected fluid Pd acting on the effective pressure surface (A1-B1). Pd1 =Pd×(A1-B1))Press to the left along the axis (i.e., with left as positive, force F1=F Ps1 +F Pd1 Acting on valve core 61).

[0099] Furthermore, the force (F) generated by the pressure of the controlled fluid Pb acting on the effective pressure-bearing surface (A1-E) of the valve core 61 is... Pb1 =Pb×(A1-E))and the force of the helical spring 62 (F b1 Pressing the force to the right (i.e., with right as positive, force F2 = F) axially to the right. Pb1 +F b1 Acting on valve core 61).

[0100] If force F1 is less than or equal to force F2, then valve core 61 moves axially to the right, such as... Figure 3 As shown, it sits on valve seat 65 (F1≤F2). That is, valve 70 is in the closed state, in other words, in the closed state.

[0101] When force F1 exceeds force F2, valve core 61 moves axially to the left (F1 > F2). That is, as Figure 2 As shown, valve 70 is in the open state, or in other words, in the unopened state. Furthermore, the farther the conical surface 66 of valve core 61 is from valve seat 65, the greater the opening degree of valve 70.

[0102] With valve 70 open, the ejected fluid Pd flowing from high-pressure space S2 into valve 70 is depressurized according to the opening degree of valve 70 and supplied to back-pressure space S3 as control fluid Pb. Valve 70 is a so-called DB valve.

[0103] Furthermore, the lubricating oil separated by the oil separator 6, together with the refrigerant, is supplied to the back pressure space S3 through valve 70.

[0104] The control fluid Pb and lubricating oil flowing into the back pressure space S3 through valve 70 are split into a portion through the through hole 9a and a portion through the connecting passage 67.

[0105] The control fluid Pb and lubricating oil are supplied to the back pressure chamber 50 through the through hole 9a. This increases the pressure of the control fluid Pb in the back pressure chamber 50 and prevents the lubricating oil in the back pressure chamber 50 from drying up or becoming excessively reduced (hereinafter referred to as drying up).

[0106] Furthermore, the control fluid Pb flowing into the connecting passage 67 is depressurized through a throttling effect and supplied to the low-pressure space S1 as the suction fluid Ps. This prevents the pressure of the control fluid Pb from rising excessively.

[0107] Furthermore, the lubricating oil flowing into the connecting passage 67, together with the refrigerant, is supplied to the low-pressure space S1 through the connecting passage 67. This prevents the lubricating oil from drying out in the low-pressure chamber 20.

[0108] When the pressure of the control fluid Pb tends to be excessive and valve 70 is closed, it is possible to prevent the control fluid Pb from being supplied to the back pressure space S3 via valve 70. On the other hand, a portion of the control fluid Pb flows into the low pressure space S1 through the connecting passage 67. As a result, the pressure of the control fluid Pb gradually decreases over time.

[0109] Furthermore, even when valve 70 is closed, lubricating oil can still be supplied to the low-pressure chamber 20 along with the refrigerant through the connecting passage 67.

[0110] As explained above, the back pressure control valve V1 of this embodiment is provided with a connection path 67 that connects the back pressure space S3 and the low pressure space S1. Therefore, the scroll compressor C can be adjusted by using the back pressure control valve V1, which has been adjusted according to the desired specifications. That is, no machining is required on the scroll compressor C side, thus the adjustment of the scroll compressor C can be performed easily.

[0111] Furthermore, inside the back pressure control valve V1, lubricating oil can be supplied from the back pressure space S3 to the low pressure space S1 via the connecting passage 67. Therefore, compared to a structure where lubricating oil is supplied to the low pressure chamber 20 after passing through the back pressure chamber 50, the path of the lubricating oil to reach the low pressure chamber 20 after separation by the oil separator 6 can be shortened. As a result, lubricating oil depletion in the low pressure chamber 20 can be prevented.

[0112] Furthermore, the back pressure space S3 and the low pressure space S1 are always connected via the connecting passage 67, so lubricating oil can be supplied from the back pressure space S3 to the low pressure space S1 regardless of the opening or closing state of the valve 70. Therefore, compared with Embodiment 4 described later (see...), Figure 11 Compared to a structure where a valve 470 is provided between the back pressure space S43 and the low pressure space S41, this structure can more reliably prevent the lubricating oil from drying out in the low pressure chamber 20.

[0113] In addition, in this embodiment, valve 70 is described as a normally closed DB valve, but it can also be a normally open DB valve by employing a force-applying unit that acts in the opening direction.

[0114] Furthermore, since the connecting path 67 is a passageway through the valve core 61, the connecting path 67 can be formed without machining the scroll compressor C.

[0115] Furthermore, since the connecting path 67 is formed in a straight line, it is consistent with the connecting path 267c, which is formed in an L-shape in cross-section in Embodiment 2 described later (see Figure 2). Figure 5 The following embodiment 6 is formed as a U-shaped connecting path 667a (see reference). Figure 17 Compared to other methods, it can reduce flow path resistance.

[0116] Furthermore, since the connecting passage 67 is formed on the axis of the valve core 61, the control fluid Pb or the suction fluid Ps acts evenly on the effective pressure surface (A1-E) and the effective pressure surface (B1-E), so the valve core 61 is not easy to tilt relative to the housing 60.

[0117] Furthermore, the back pressure control valve V1 uses the force (F) generated by the pressure of the ejected fluid Pd. Pd1 ) and the force (F) generated by the pressure of the inhaled fluid Ps. Ps1 The sum of ) and the force (F) generated by the pressure of the control fluid Pb Pb1 The force (F) of the coil spring 62 and the force of the coil spring 62 b1 The valve opening is adjusted by the total balance of the pressure in the high-pressure chamber 30 and the low-pressure chamber 20, so that the valve opening can be smoothly changed according to the pressure changes in the high-pressure chamber 30 and the low-pressure chamber 20, and the pressure in the back pressure chamber 50 can be adjusted immediately.

[0118] Furthermore, the effective pressure-bearing surface (B1-E) affected by the pressure of the intake fluid Ps is larger than the effective pressure-bearing surface (A1-B1) affected by the pressure of the ejected fluid Pd ((B1-E) > (A1-B1)). Therefore, the back pressure control valve V1 can suppress the influence of the ejected fluid Pd pressure, which is relatively higher than the intake fluid Ps pressure, while relatively increasing the influence of the intake fluid Ps pressure. As a result, it can suppress the valve core 61 from moving rapidly due to the rapid pressure change of the ejected fluid Pd.

[0119] Furthermore, the effective pressure-bearing surface (A1-E) affected by the pressure of the control fluid Pb is larger than the effective pressure-bearing surface (A1-B1) affected by the pressure of the ejected fluid Pd ((A1-E) > (A1-B1)). Therefore, the back pressure control valve V1 can suppress the influence of the ejected fluid Pd, which has a relatively higher pressure than the control fluid Pb, while relatively increasing the influence of the control fluid Pb. As a result, it can suppress the rapid movement of the valve core 61 due to the rapid pressure change of the ejected fluid Pd.

[0120] Furthermore, in this embodiment, the case where the connecting path 67 is formed as a straight line has been described, but it can also be formed as an L-shaped connecting path 267c as in Embodiment 2 described later (see...). Figure 5 The following embodiment 6 is formed as a U-shaped connecting path 667a (see reference). Figure 17 In a similar manner, the shape of the connecting path can be appropriately altered.

[0121] Furthermore, the case where the connecting path 67 is formed on the axis of the valve core 61 has been explained, but it can also be formed at a position away from the axis of the valve core 61, or it can be inclined relative to the axis of the valve core 61, or multiple paths can be formed.

[0122] Furthermore, in this embodiment, the structure in which the valve core 61 forms a connecting passage 67 has been described, but reference can also be made to the modified example 1-1 shown. Figure 4 The housing 60A has a connecting passage 67A, and a valve core 61A without a connecting passage is used. Alternatively, the housing 60A with the connecting passage 67A and the valve core 61A with the connecting passage 67A can be used together.

[0123] More specifically, the connecting path 67A extends axially and in a straight line through the shell 60A, covering the sides of the low-pressure space S1 and the walls of the back-pressure space S3.

[0124] The force acting on valve core 61A is described below. The effective pressure-bearing surface of valve core 61A, which is the back pressure-bearing surface, is A1, which is acted upon by the pressure of control fluid Pb.

[0125] The effective pressure-bearing surface of the valve core 61A, which is the high-pressure pressure-bearing surface, is (A1-B1) when the pressure of the ejected fluid Pd acts on it.

[0126] The effective pressure-bearing surface of the valve core 61A, which is the low-pressure pressure-bearing surface, is B1, which is acted upon by the pressure of the suction fluid Ps.

[0127] The force (F) generated when the valve core 61A is subjected to the pressure of the ejected fluid Pd on the effective pressure-bearing surface (A1-B1) Pd1 =Pd×(A1-B1)) and the force (F) generated by the pressure of the inhaled fluid Ps acting on the effective pressure-bearing surface B1. Ps11 =Ps×B1) Press to the left along the axis (i.e., with left as positive, force F) 11 =F Ps11 +F Pd1 Acting on valve core 61).

[0128] Furthermore, the force (F) generated by the pressure of the controlled fluid Pb acting on the effective pressure-bearing surface A1 of the valve core 61A is... Pb11 =Pb×A1) and the force of the helical spring 62 (F) b1 Press the force F to the right (i.e., with right as positive, force F) along the axis. 12 =F Pb11 +F b1 Acting on valve core 61).

[0129] Even with this structure, it is possible to form the connecting path 67A without processing the scroll compressor C.

[0130] Furthermore, by forming a connecting passage 67A in the housing 60A and omitting the connecting passage of the valve core 61A, it is easier to balance the forces generated by the fluid pressure acting on each pressure-bearing surface of the valve core 61A. That is, it is easier to make the valve core 61A move more stably.

[0131] Furthermore, when the connecting path is formed in the housing, its shape is not limited to a straight line and can be appropriately modified. For example, it can also be a connecting path 267Ab formed as an L-shaped cross-section with up-and-down flipping, as in the modified example 2-1 of Embodiment 2 described later (see reference). Figure 6 That kind of shape.

[0132] Furthermore, when connecting paths are formed within the housing, their quantity and configuration can be appropriately changed.

[0133] Example 2

[0134] Next, refer to Figures 5-7 The valve of Example 2 will be described. Furthermore, repeated structural descriptions identical to those of Example 1 will be omitted.

[0135] like Figure 5As shown, the back pressure control valve V2 in this embodiment 2 is normally closed and mainly consists of a housing 260, a valve core 261, and a pressure-sensitive element 262.

[0136] The housing 260 is divided into two low-pressure spaces S21 and S21' that communicate with the low-pressure chamber 20, a high-pressure space S22 that communicates with the high-pressure chamber 30, and a back-pressure space S23 that communicates with the back-pressure chamber 50. Alternatively, the housing 260 may be divided into at least a portion of the low-pressure spaces S21 and S21', the high-pressure space S22, and the back-pressure space S23.

[0137] The housing 260 is composed of a first cylindrical segment 263 and a second cylindrical segment 264.

[0138] A dividing wall 263e is formed on the axial left side of the first dividing body 263. The dividing wall 263e has a valve hole 263a and a valve seat 265. The valve seat 265 and the tapered surface 266 of the valve core 261 together constitute a valve 270 for opening and closing control of the flow path 268 between the valve seat 265 and the tapered surface 266.

[0139] A dividing wall portion 263f is formed at the right end of the first dividing body 263, and the dividing wall portion 263f has a through hole 263g.

[0140] The space sandwiched between the partitioned walls 263e and 263f in the axial direction is the high-pressure space S22. The high-pressure space S22 is connected to the high-pressure chamber 30 via a connecting hole 263d formed in the first partition 263.

[0141] Furthermore, the space to the right of the dividing wall portion 263f is a low-pressure space S21' where the suction fluid Ps flows in. Specifically, the other low-pressure space S21' is divided by the dividing wall portion 263f and the recessed portion of the back pressure control valve V2 provided on the fixed scroll plate 41.

[0142] The first segment 263 has an annular protrusion 263c protruding to the left in the axial direction. The annular protrusion 263c is fitted and fixed to the annular stepped portion 264b, which is provided at the right end opening of the second segment 264.

[0143] A dividing wall portion 264a is formed at the axial center of the second dividing body 264, and the dividing wall portion 264a has a through hole 264d.

[0144] The space enclosed by the dividing wall portion 264a of the second dividing body 264 and the dividing wall portion 263e of the first dividing body 263 is a back pressure space S23. The back pressure space S23 communicates with the back pressure chamber 50 via a connecting hole 264c formed in the second dividing body 264.

[0145] A cover component 209 is screwed onto the inner circumferential surface of the left end opening of the second segment 264 in a sealed manner.

[0146] The space sandwiched axially by the dividing wall 264a of the second dividing body 264 and the cover member 209 is a low-pressure space S21. The low-pressure space S21 communicates with the low-pressure chamber 20 via a connecting hole 264e formed in the second dividing body 264.

[0147] A pressure-sensitive element 262 is disposed between the cover component 209 and the valve core 261.

[0148] The pressure-sensitive element 262 consists of a corrugated metal main body 262a and a closing part 262b that closes the opening at the axial right end of the main body 262a. The pressure-sensitive element 262 is a bellows that maintains an internal vacuum. The main body 262a also functions as a force-applying unit, applying force to the valve core 261 in the closing direction. Alternatively, a compression spring, serving as a force-applying unit, can be separately disposed between the cover member 209 and the closing part 262b. The opening at the axial left end of the main body 262a is closed by the cover member 209.

[0149] The closing portion 262b has a recess 262e and a connecting passage 267a. The recess 262e is recessed to the left axially from the right end face of the closing portion 262b and opens to the right axially.

[0150] The connecting passage 267a is formed in an L-shaped cross-section, extending from the outer periphery of the closure 262b to the inner diameter side, and extending approximately perpendicularly to the right side of the radial center and axial direction of the closure 262b. The connecting passage 267a communicates with the low-pressure space S21 and the recess 262e.

[0151] The valve core 261 has a large-diameter main body portion 261a, a medium-diameter main body portion 261b extending axially to the left from the large-diameter main body portion 261a, a small-diameter main body portion 261c protruding axially to the left from the medium-diameter main body portion 261b, and an extension shaft portion 261d extending axially to the right from the large-diameter main body portion 261a.

[0152] The large-diameter main body 261a has a tapered surface 266 that narrows to the right along the axial direction. The large-diameter main body 261a is disposed in the back pressure space S23.

[0153] The middle diameter main body 261b is disposed in the back pressure space S23.

[0154] The small-diameter main body portion 261c is inserted through the through hole 264d from the back pressure space S23 side, and the end portion of the small-diameter main body portion 261c is sealed and fitted into the recess 262e of the closing portion 262b within the low pressure space S21. Alternatively, the small-diameter main body portion 261c may not be sealed, but may be fitted into the recess 262e of the closing portion 262b with a gap.

[0155] The gap between the inner circumferential surface of the dividing wall portion 264a constituting the through hole 264d and the outer circumferential surface of the small-diameter main body portion 261c is extremely small, so the refrigerant hardly moves between the back pressure space S23 and the low pressure space S21 through this gap. Furthermore, the inner circumferential surface of the dividing wall portion 264a and the outer circumferential surface of the small-diameter main body portion 261c are smooth surfaces with the same diameter throughout the entire axial range, and the two surfaces can slide relative to each other.

[0156] The extension shaft portion 261d is inserted through the through hole 263g. The diameter of the extension shaft portion 261d is larger than the diameter of the middle diameter main body portion 261b.

[0157] The gap between the inner circumferential surface of the dividing wall portion 263f constituting the through hole 263g and the outer circumferential surface of the extending shaft portion 261d is extremely small, so the refrigerant hardly moves between the high-pressure space S22 and the low-pressure space S21' through this gap. Furthermore, the inner circumferential surface of the dividing wall portion 263f and the outer circumferential surface of the extending shaft portion 261d are smooth surfaces with the same diameter throughout the entire axial range, and the two surfaces can slide relative to each other.

[0158] Furthermore, the valve core 261 has connecting passages 267b and 267c.

[0159] The connecting passage 267b is formed in an L-shape with its cross-section flipped left and right, extending axially to the right from the left end of the small diameter main body 261c, and extending approximately perpendicularly to the outer diameter side on the left side of the middle diameter main body 261b. The connecting passage 267b is formed to always communicate with the back pressure space S23 within the movement range of the valve core 261.

[0160] Furthermore, the connecting path 267b is also connected to the recess 262e of the pressure-sensitive body 262. That is, the connecting path 267b is connected to the connecting path 267a of the pressure-sensitive body 262.

[0161] The connecting path 267c is formed in an L-shaped cross section, extending from the right end face of the extension shaft portion 261d toward the left side of the axial direction, and extending approximately perpendicularly to the outer diameter side at the axial center of the middle diameter main body portion 261b.

[0162] The connecting path 267c is configured to always be connected to the low-pressure space S21' and the back-pressure space S23 within the movement range of the valve core 261.

[0163] In valve core 261, the pressures of control fluid Pb and ejected fluid Pd act on the large-diameter main body 261a, the pressure of control fluid Pb acts on the medium-diameter main body 261b, and the pressure of suction fluid Ps acts on the extension shaft 261d.

[0164] The effective pressure-bearing surface of the valve core 261, which acts as the back pressure-bearing surface, is approximately the same as the area of ​​the valve seat 265 where the conical surface 266 contacts the valve seat 265 when it is seated. This area is the portion of the flow path section A2 of the valve seat 265 that is further outward than the flow path section E of the connecting passage 267c (A2-E), minus the portion of the small-diameter main body section C2 that is further outward than the flow path section E of the connecting passage 267b (C2-E). Hereinafter, the effective pressure-bearing surface of the valve core 261, which acts as the back pressure-bearing surface, is referred to as "effective pressure-bearing surface (A2-C2)".

[0165] The effective pressure-bearing surface of the valve core 261, which is acted upon by the pressure of the ejected fluid Pd, is approximately the same as the area (A2-B2) obtained by subtracting the portion (A2-E) of the flow path section A2 of the valve seat 265 that is located outside the flow path section E of the connecting passage 267c from the portion (A2-E) of the section B2 of the extended shaft portion 261d that is located outside the flow path section E of the connecting passage 267c. Hereinafter, the effective pressure-bearing surface of the valve core 261 acted upon by the pressure of the ejected fluid Pd will be referred to as "effective pressure-bearing surface (A2-B2)".

[0166] The cross section B2 of the extended shaft portion 261d is larger and wider in diameter than the cross section C2 of the small-diameter body portion 261c (B2 > C2). As a result, the effective pressure-bearing surface (A2-C2) is larger than the effective pressure-bearing surface (A2-B2) ((A2-C2) > (A2-B2)).

[0167] The effective pressure-bearing surface of the valve core 261, which is the low-pressure pressure-bearing surface, acting on the pressure of the intake fluid Ps, is approximately the same as the portion (B2-E) of the cross section B2 of the extended shaft portion 261d that is located on the outer side compared to the flow path cross section E of the connecting passage 267c. Hereinafter, the effective pressure-bearing surface of the valve core 261 acting on the pressure of the intake fluid Ps will be referred to as "effective pressure-bearing surface (B2-E)".

[0168] Furthermore, regardless of the opening or closing state of valve 270, the closed portion 262b of pressure-sensitive body 262 is always positioned axially to the left, away from the dividing wall portion 264a. That is, the pressure of the suction fluid Ps in the low-pressure space S21 always acts on pressure-sensitive body 262 axially to the left.

[0169] The effective pressure-bearing surface of the pressure-sensitive body 262, which is the low-pressure receiving surface, is approximately the same as the area (D2-C2) obtained by subtracting the portion (D2-E) of the cross-section C2 of the small-diameter main body 261c that is the portion (D2-E) of the effective pressure-bearing surface D2 of the pressure-sensitive body 262 that is located outside the flow path cross-section E of the connecting passage 267a. Hereinafter, the effective pressure-bearing surface of the pressure-sensitive body 262, which is the portion (D2-E) of the small-diameter main body 261c that is located outside the connecting passage 267b.

[0170] Furthermore, in this specification, the interior of the pressure-sensitive body 262 is a vacuum as described above, and therefore it is considered that the interior of the pressure-sensitive body 262 is not affected.

[0171] Next, the opening and closing operation of the back pressure control valve V2 will be explained. In the housing 260, the suction fluid Ps flows into the low-pressure spaces S21 and S21', the ejection fluid Pd flows into the high-pressure space S22, and the control fluid Pb flows into the back pressure space S23.

[0172] The force (F) generated by the pressure of the fluid Ps drawn into the valve core 261 acting on the effective pressure-bearing surface (B2-E) Ps21 =Ps×(B2-E)), the force (F) generated by the pressure of the ejected fluid Pd acting on the effective pressure-bearing surface (A2-B2). Pd2 =Pd×(A2-B2))and the force (F) generated by the pressure of the inhaled fluid Ps acting on the effective pressure-bearing surface (D2-C2). Ps22 =Ps×(D2-C2))Press to the left along the axis (i.e., with left as positive, force F 21 =F Ps21 +F Pd2 +F Ps22 Acting on valve core 261).

[0173] Furthermore, the force (F) generated by the pressure of the controlled fluid Pb acting on the effective pressure-bearing surface (A2-C2) of the valve core 261 is... Pb2 =Pb×(A2-C2))and the force of pressure-sensitive body 262 (F) b2 Press the force F to the right (i.e., with right as positive, force F) along the axis. 22 =F Pb2 +F b2 Acting on valve core 261).

[0174] If force F 21 For force F 22 Then, the valve core 261 moves axially to the right and sits on the valve seat 265 (F). 21 ≤F 22 That is, valve 270 becomes closed. Furthermore, in pressure-sensitive body 262, while the main body 262a extends, the closing part 262b moves axially to the right as an integral part of valve core 261.

[0175] When force F 21 Exceeding force F 22 At that time, valve core 261 moves axially to the left (F 21 >F 22That is, valve 270 is in the open state. The farther the conical surface 266 of valve core 261 is from valve seat 265, the greater the opening degree of valve 270. Furthermore, the closing portion 262b of pressure-sensitive body 262 moves axially to the left as integrally with valve core 261 while contracting the main body portion 262a.

[0176] With valve 270 open, the ejected fluid Pd flowing from high-pressure space S22 into valve 270 is depressurized according to the opening degree of valve 270 and supplied to back pressure space S23 as control fluid Pb.

[0177] The control fluid Pb flowing into the back pressure space S23 through valve 270 is divided into a portion through the connecting hole 264c, a portion through connecting paths 267a and 267b, and a portion through connecting path 267c.

[0178] The control fluid Pb is supplied to the back pressure chamber 50 through the connecting hole 264c. This allows the pressure of the control fluid Pb in the back pressure chamber 50 to be increased.

[0179] Furthermore, the control fluid Pb flowing into connecting passages 267a and 267b is depressurized through a throttling effect and provided as suction fluid Ps to the low-pressure space S21 on one side. Similarly, the control fluid Pb flowing into connecting passage 267c is depressurized through a throttling effect and provided as suction fluid Ps to the low-pressure space S21' on the other side.

[0180] With valve 270 closed, the control fluid Pb is prevented from being supplied to the back pressure space S23. On the other hand, a portion of the control fluid Pb flows not only into one low-pressure space S21 through connecting passages 267a and 267b, but also into the other low-pressure space S21' through connecting passage 267c. As a result, the pressure of the control fluid Pb can be reduced in a shorter time than in Embodiment 1 described above.

[0181] As explained above, the back pressure control valve V2 of this embodiment is provided with connecting passages 267a and 267b that connect the back pressure space S23 to one low-pressure space S21, and a connecting passage 267c that connects the back pressure space S23 to the other low-pressure space S21'. Therefore, the scroll compressor C can be adjusted by using the back pressure control valve V2, which has been adjusted according to the desired specifications. That is, no machining is required on the scroll compressor C side, thus the adjustment of the scroll compressor C can be performed easily.

[0182] Furthermore, in the back pressure control valve V2, low-pressure spaces S21 and S21' are located at both axial ends of the housing 260, and the pressure of the suction fluid Ps acts on the valve core 261 and the pressure-sensitive element 262, respectively. As a result, the back pressure control valve V2 makes it easier for the valve core 261 to move away from the valve seat 265.

[0183] Furthermore, it is sufficient to form at least one of the connecting paths 267a, 267b and 267c.

[0184] Furthermore, in this embodiment, the structure in which the valve core 261 forms connecting passages 267b, 267a and connecting passage 267c has been described, but the modified example 2-1 can also be referred to. Figure 6 The housing 260A forms connecting paths 267Aa and 267Ab, while the valve core 261A and pressure-sensitive body 262A, which do not form connecting paths, are used.

[0185] More specifically, the connecting path 267Aa axially penetrates the portion of the dividing wall 264Aa of the second dividing body 264A that is closer to the outer diameter than the through hole 264d. The connecting path 267Aa is connected to the back pressure space S23 and one of the low pressure spaces S21.

[0186] The connecting path 267Ab extends axially to the left from the right end of the peripheral wall of the first partition 263A, and extends axially to the left at the axial center of the partition wall 263Ae in an inwardly inclined manner. The connecting path 267Ab is formed at a position that is out of phase with the connecting hole 263d in the circumferential direction. The connecting path 267Ab communicates with the back pressure space S23 and the low pressure space S21' on the other side.

[0187] The force acting on valve core 261A is explained below. The effective pressure-bearing surface of valve core 261A, which is the back pressure-bearing surface, is (A2-C2) when the pressure of control fluid Pb acts on it.

[0188] The effective pressure-bearing surface of valve core 261A, which is the high-pressure pressure-bearing surface, is (A2-B2) when the pressure of the ejected fluid Pd acts on it.

[0189] The effective pressure-receiving surface of the valve core 261A, which is the low-pressure receiving surface, is B2, which is acted upon by the pressure of the intake fluid Ps. Furthermore, the effective pressure-receiving surface of the pressure-sensitive element 262A, which is the low-pressure receiving surface, is (D2-C2).

[0190] The force (F) generated by the pressure of the ejected fluid Pd acting on the effective pressure-bearing surface (A2-B2) of the valve core 261A Pd2 =Pd×(A2-B2),The force (F) generated by the pressure of the inhaled fluid Ps acting on the effective pressure-bearing surface (D2-C2) Ps22 =Ps×(D2-C2))and the force (F) generated by the pressure of the inhaled fluid Ps acting on the effective pressure-bearing surface B2. Ps23 =Ps×B2) Press to the left along the axis (i.e., with left as positive, force F) 23 =F Pd2 +F Ps22 +FPs23 acts on valve core 61).

[0191] Furthermore, the force (F) generated by the pressure of the controlled fluid Pb acting on the effective pressure-bearing surface (A2-C2) of the valve core 261A is... Pb2 =Pb×(A2-C2))and the force of pressure-sensitive body 262 (F) b2 Press the force F to the right (i.e., with right as positive, force F) along the axis. 22 =F Pb2 +F b2 (Action applied to valve core 261A).

[0192] Furthermore, reference can also be made to another variation, 2-2. Figure 7 A gap is provided between the second segment 264B of the housing 260B and the valve core 261A, and this gap serves as a connecting path 267B that is always connected to the adjacent back pressure space S23 and one of the low pressure spaces S21. The flow path cross-section of the connecting path 267B is preferably a flow path cross-section having the same throttling effect as the connecting path described in Embodiment 1, etc. Alternatively, the housing 260B, the pressure-sensitive element 262 having the connecting path 267a, and the valve core 261 having the connecting paths 267b and 267c can be used together.

[0193] More specifically, the diameter of the through hole 264Bd of the second segment 264B, i.e., the inner diameter of the dividing wall portion 264Ba, is slightly larger than the diameter of the small-diameter main body portion 261c of the valve core 261A. This ensures a radial clearance between the inner circumferential surface of the dividing wall portion 264Ba and the outer circumferential surface of the small-diameter main body portion 261Ac.

[0194] Furthermore, the force acting on the valve core 261A is approximately the same as that in the aforementioned modified example 2-1.

[0195] If such a structure is used, then the connecting path 267B can be easily constructed without processing the scroll compressor C.

[0196] Furthermore, the connecting passage 267B can be easily constructed without the need for machining such as creating a connecting passage through the housing 260B or valve core 261A.

[0197] Furthermore, the valve core 261A is fixed to the pressure-sensitive body 262A and moves while sliding in contact with the dividing wall portion 263f, thus preventing the valve core 261A from tilting relative to the housing 260B. This allows for a more reliable connection of the communication path 267B.

[0198] Furthermore, the case where the diameter of the through hole 264Bd is slightly larger than the diameter of the small-diameter main body 261c has been described, but it is not limited to this. For structures that ensure clearance, appropriate modifications can be made. For example, the connecting path 367B, as described later in Modification 3-2 of Embodiment 3 (refer to...) Figure 10In this way, a communication path is formed between the housing and the valve core by forming a groove that opens toward the other side and communicates with the low-pressure space S21 and the back-pressure space S23 respectively in at least one of the small-diameter main body portion of the valve core and the dividing wall portion of the second dividing body.

[0199] Example 3

[0200] Next, refer to Figures 8-10 The valve of Example 3 will be described. Furthermore, repeated structural descriptions identical to those in Example 1 will be omitted.

[0201] like Figure 8 As shown, the back pressure control valve V3 in this embodiment 3 is normally closed and mainly consists of a housing 360, a pressure-sensitive body 361 having a sealing part 361b as a valve core, a helical spring 362, a pressure driving body 371 as a valve core, and a disc spring 372 as a force-applying unit that applies force to the pressure driving body 371 in the opening direction.

[0202] The housing 360 has a low-pressure space S31 communicating with the low-pressure chamber 20, a high-pressure space S32 communicating with the high-pressure chamber 30, and a back-pressure space S33 communicating with the back-pressure chamber 50. Alternatively, the housing 360 may be divided into at least a portion of the low-pressure space S31, the high-pressure space S32, and the back-pressure space S33.

[0203] The housing 360 is composed of a first cylindrical segment 363 and a second cylindrical segment 364.

[0204] A dividing wall portion 363e is formed at the axial center of the first dividing body 363. The dividing wall portion 363e has a valve hole 363a and a valve seat 365. The valve seat 365 and the curved surface 366 of the pressure-sensitive body 361 together constitute a valve 370 for controlling the opening and closing of the flow path 368 between the valve seat 365 and the curved surface 366.

[0205] A cover component 369 with a through hole 369a is screwed onto the opening at the right end of the first segment 363.

[0206] In the first partition 363, in the space where the partition wall 363e and the cover member 369 are sandwiched in the axial direction, a pressure drive body 371 and a disc spring 372 are arranged sequentially from the left side.

[0207] The pressure drive body 371 has a cylindrical large-diameter main body 371a and a small-diameter main body 371b that protrudes axially to the left from the center of the left end face of the large-diameter main body 371a.

[0208] The large-diameter main body 371a has an annular groove 371c that is recessed from the axial center of the outer peripheral surface of the large-diameter main body 371a toward the inner diameter side and opens on the outer diameter side.

[0209] An O-ring 373, serving as a sealing unit, is disposed in the annular groove 371c. The O-ring 373 allows axial movement of the pressure drive body 371 and seals the pressure drive body 371 with the peripheral wall of the first segment 363.

[0210] The large-diameter main body 371a and O-ring 373 divide the space sandwiched between the dividing wall 363e and the cover part 369 in the axial direction into a back pressure space S33 and a low pressure space S31.

[0211] The back pressure space S33 is the space on the left side of the large-diameter main body 371a, i.e. the dividing wall 363e side, and is connected to the back pressure chamber 50 through the connecting hole 363d formed in the first dividing body 363.

[0212] The low-pressure space S31 is the space on the right side of the large-diameter main body 371a, i.e., the cover member 369 side, and is connected to the low-pressure chamber 20 through the through hole 369a.

[0213] Furthermore, the large-diameter main body 371a has an axially extending connecting passage 367 formed on the outer diameter side compared to the small-diameter main body 371b. The connecting passage 367 is connected to the back pressure space S33 and the low pressure space S31.

[0214] The left end face of the main body 371b of the small diameter is a flat surface.

[0215] The disc spring 372 is arranged in a compressed state between the large-diameter main body 371a of the pressure drive body 371 and the cover member 369 in the axial direction.

[0216] A second segment 364 is embedded and fixed in the opening on the left side of the first segment 363.

[0217] A dividing wall portion 364a is formed at the left end of the second dividing body 364, and the dividing wall portion 364a has a through hole 364d.

[0218] The space sandwiched axially by the dividing wall portion 364a of the second dividing body 364 and the dividing wall portion 363e of the first dividing body 363 is the high-pressure space S32. The high-pressure space S32 is connected to the high-pressure chamber 30 via a connecting hole 364e formed in the second dividing body 364.

[0219] The cover component 309 is screwed into the through hole 364d and installed in a sealed manner on the dividing wall portion 364a.

[0220] The pressure-sensitive element 361 consists of a main body 361a and a sealing part 361b that serves as a valve core. The pressure-sensitive element 361 is a bellows whose interior is kept under vacuum. The pressure-sensitive element 361 can hardly generate any force, but it can also be a structure that generates a force in the closing direction of the valve 370. If it is such a structure, the helical spring 362 can be omitted.

[0221] The closure portion 361b has a circular plate portion 361c that extends outward in diameter. A helical spring 362, which is inserted into the main body portion 361a, is disposed in a compressed state between the circular plate portion 361c and the dividing wall portion 364a of the second dividing body 364.

[0222] Furthermore, a hemispherical protrusion protruding axially to the right is formed at the center of the right end face of the circular plate portion 361c. The end face of this protrusion is a spherical curved surface 366.

[0223] The curved surface 366 of the pressure-sensitive body 361 and the left end face of the small-diameter main body 371b of the pressure driving body 371 are kept in abutting state by means of the force of the helical spring 362 and the disc spring 372.

[0224] The pressures of the control fluid Pb and the ejected fluid Pd act on the pressure-sensitive body 361.

[0225] The effective pressure-bearing surface of the pressure-sensitive body 361, which acts as the back pressure-bearing surface, is approximately the same as the portion of the flow path section A3 of the valve seat 365 where the curved surface 366 contacts the small-diameter main body portion 371b of the pressure drive body 371, located on the outer diameter side of the part where it abuts the curved surface 366 when seated on the valve seat 365. Since the contact between the curved surface 366 and the left end face of the small-diameter main body portion 371b is a point contact, it is considered not to affect the effective pressure-bearing surface. Hereinafter, the effective pressure-bearing surface of the pressure-sensitive body 361 acting on the pressure of the control fluid Pb will be referred to as "effective pressure-bearing surface A3".

[0226] The effective pressure-bearing surface of the pressure-sensitive element 361, which is the high-pressure receiving surface, is approximately the same as the portion of the effective pressure-bearing surface D3 of the pressure-sensitive element 361 located on the outer side of the flow path section A3 of the valve seat 365. Hereinafter, the effective pressure-bearing surface of the pressure-sensitive element 361, which is the pressure of the ejected fluid Pd, will be referred to as "effective pressure-bearing surface (D3-A3)".

[0227] The pressures of the control fluid Pb and the intake fluid Ps act on the pressure drive body 371.

[0228] The effective pressure-bearing surface of the pressure-driven body 371, which acts as the back pressure-bearing surface, is approximately the same as the portion (B3-E) of the cross-section B3 of the large-diameter main body 371a that is located on the outer side compared to the flow path cross-section E of the connecting passage 367. Hereinafter, the effective pressure-bearing surface of the pressure-driven body 371, which acts as the back pressure-bearing surface, will be referred to as "effective pressure-bearing surface B3b".

[0229] The effective pressure-bearing surface of the pressure-driven body 371, which is a low-pressure pressure-bearing surface, is approximately the same as the portion (B3-E) of the cross-section B3 of the large-diameter main body 371a that is located on the outer side of the flow path cross-section E of the connecting passage 367. Hereinafter, the effective pressure-bearing surface of the pressure-driven body 371, which is acted upon by the pressure of the suction fluid Ps, will be referred to as "effective pressure-bearing surface B3s".

[0230] Next, the opening and closing operation of the back pressure control valve V3 will be explained. In the housing 360, the suction fluid Ps flows into the low-pressure space S31, the ejection fluid Pd flows into the high-pressure space S32, and the control fluid Pb flows into the back pressure space S33.

[0231] The pressure-sensitive body 361's closed portion 361b is subjected to the pressure of the controlled fluid Pb, resulting in a force (F) on the effective pressure-bearing surface A3. Pb31 =Pb×A3), the force (F) generated by the pressure of the ejected fluid Pd acting on the effective pressure-bearing surface (D3-A3). Pd3 =Pd×(D3-A3)), the force (F) generated by the pressure of the inhaled fluid Ps acting on the effective pressure-bearing surface B3s. Ps3 =Ps×B3s) and the force of the disc spring 372 (F) b32 Press the force F to the left along the axis (i.e., with left as positive, force F) 31 =F Pb31 +F Pd3 +F Ps3 +F b32 Acting on pressure-sensitive body 361).

[0232] Furthermore, the pressure of the closed portion 361b of the pressure-sensitive body 361 is applied to the effective pressure-bearing surface B3b by the pressure of the controlled fluid Pb, generating a force (F). Pb32 =Pb×B3b) and the force of the helical spring 362 (F) b31 Press the force F to the right (i.e., with right as positive, force F) along the axis. 32 =F Pb32 +F b31 Acting on pressure-sensitive body 361).

[0233] If force F 31 For force F 32 Next, in the pressure-sensitive body 361, while the main body 361a extends, the sealing part 361b moves axially to the right and sits on the valve seat 365 (F). 31 ≤F 32 That is, valve 370 becomes closed. Furthermore, pressure actuator 371 and pressure-sensitive element 361 move axially to the right as a unit.

[0234] When force F 31 Exceeding force F 32At that time, the closed portion 262b of the pressure-sensitive body 361 moves axially to the left while the main body portion 361a contracts (F 31 >F 32 That is, valve 370 becomes open. Furthermore, the farther the curved surface 366 of the pressure-sensitive body 361 is from the valve seat 365, the greater the opening degree of valve 370. Also, the pressure drive body 371 and the pressure-sensitive body 361 move axially to the left as a unit.

[0235] With valve 370 open, the ejected fluid Pd flowing from high-pressure space S32 into valve 370 is depressurized according to the opening degree of valve 370 and supplied to back pressure space S33 as control fluid Pb.

[0236] The control fluid Pb flowing into the back pressure space S33 through valve 370 is split into a portion through the connecting hole 363d and a portion through the connecting path 367.

[0237] The control fluid Pb is supplied to the back pressure chamber 50 through the connecting hole 363d. This allows the pressure of the control fluid Pb in the back pressure chamber 50 to be increased.

[0238] Furthermore, the control fluid Pb flowing into the connecting path 367 is depressurized by the throttling effect and provided to the low-pressure space S31 as the suction fluid Ps.

[0239] With valve 370 closed, the supply of control fluid Pb to the back pressure space S33 is prevented. On the other hand, a portion of the control fluid Pb flows into the low pressure space S31 through the connecting passage 367. As a result, the pressure of the control fluid Pb gradually decreases over time.

[0240] As explained above, the back pressure control valve V3 of this embodiment is provided with a connection path 367 that connects the back pressure space S33 and the low pressure space S31. Therefore, the scroll compressor C can be adjusted by using the back pressure control valve V3, which has been adjusted according to the desired specifications. That is, no machining is required on the scroll compressor C side, so the adjustment of the scroll compressor C can be performed easily.

[0241] Furthermore, the low-pressure space S31 into which the suction fluid Ps flows is positioned opposite to the high-pressure space S32 into which the control fluid Pb flows, relative to the back-pressure space S33 into which the ejected fluid Pd flows. This facilitates the formation of the effective pressure-bearing surface B3s and the effective pressure-bearing surface (D3-A3) in a manner that reduces the influence of the pressure of the ejected fluid Pd, which has a relatively higher pressure compared to the suction fluid Ps, while increasing the influence of the pressure of the suction fluid Ps. Specifically, the area design of the effective pressure-bearing surface D3 of the pressure-sensitive element 361, the flow path cross-section A3 of the valve seat 365, and the cross-section B3 of the pressure drive element 371 in this embodiment is readily feasible.

[0242] Furthermore, due to the force (F) of the disc spring 372 b32 The pressure is applied to the pressure-sensitive element 361 in an axial direction to the left via the pressure actuator 371. This makes it easy to move the pressure-sensitive element 361 in the valve opening direction and to adjust the valve opening using the disc spring 372.

[0243] Furthermore, since the curved surface 366 of the closed portion 361b of the pressure-sensitive body 361 abuts against the left end face of the pressure driving body 371, even when the pressure driving body 371 tilts relative to the axis of the pressure-sensitive body 361 and presses the pressure-sensitive body 361 at an angle relative to the axis of the pressure-sensitive body 361, it is easy to move along the axis of the pressure-sensitive body 361.

[0244] Furthermore, the pressure-driven body 371 is aligned with the axis of the first segment 363 by means of the elastic force of the O-ring 373. Thus, it is easy to move the pressure-sensitive body 361 along its axis.

[0245] Furthermore, in this embodiment, the structure in which the pressure drive body 371 has a connecting passage 367 has been described, but reference can also be made to the modified example 3-1 shown. Figure 9 The housing 360A has a connecting passage 367A, and the pressure actuator 371A does not have a connecting passage.

[0246] More specifically, the connecting passage 367A extends axially through the connecting hole 363d and the connecting groove 363g, penetrating the peripheral wall of the first segment 363A. The connecting groove 363g is recessed to the left axially from the right end of the peripheral wall of the first segment 363A and opens to the right axially and radially to both sides. The connecting groove 363g communicates with the low-pressure space S31.

[0247] The forces acting on the pressure-sensitive body 361 will now be described. The effective pressure-bearing surface of the pressure-sensitive body 361, acting as the back pressure-bearing surface, is A3, which is acted upon by the pressure of the control fluid Pb. The effective pressure-bearing surface of the pressure-driven body 371A, acting as the back pressure-bearing surface, is B3, which is acted upon by the pressure of the suction fluid Pb. Hereinafter, the effective pressure-bearing surface of the pressure-driven body 371A, acting as the pressure of the suction fluid Pb, will be referred to as "effective pressure-bearing surface B3B".

[0248] The effective pressure-bearing surface of the pressure-sensitive body 361, which is acted upon by the pressure of the ejected fluid Pd, is (D3-A3).

[0249] The effective pressure-bearing surface of the pressure drive body 371A, which is a low-pressure pressure-bearing surface, is B3 when the pressure of the intake fluid Ps acts on it. Hereinafter, the effective pressure-bearing surface of the pressure drive body 371A when the pressure of the intake fluid Ps acts on it will be referred to as "effective pressure-bearing surface B3S".

[0250] The force (F) generated when the pressure-sensitive body 361 is subjected to the pressure of the ejected fluid Pd on the effective pressure-bearing surface (D3-A3) Pd3 =Pd×(D3-A3)), the force (F) generated by the pressure of the control fluid Pb acting on the effective pressure surface A3. Pb31 =Pb×A3), the force (F) generated by the pressure of the inhaled fluid Ps acting on the effective pressure-bearing surface B3S. Ps33 =Ps×B3S) and the force of the disc spring 372 (F) b32 Press the force F to the left along the axis (i.e., with left as positive, force F) 33 =F Pd3 +F Pb31 +F Ps33 +F b32 Acting on pressure-sensitive body 361).

[0251] Furthermore, the pressure sensor 361 is subjected to the pressure of the controlled fluid Pb, which acts on the effective pressure-bearing surface B3B, generating a force (F). Pb34 =Pb×B3B) and the force of the helical spring 362 (F) b31 Press the force F to the right (i.e., with right as positive, force F) along the axis. 34 =F Pb34 +F b31 Acting on pressure-sensitive body 361).

[0252] Furthermore, reference can also be made to the modified example 3-2 shown. Figure 10 The large-diameter main body 371Ba of the pressure drive body 371B omits the annular groove 371c and forms a groove-shaped connecting passage 367B that extends in a straight line.

[0253] More specifically, the connecting passage 367B is recessed from the outer periphery of the large-diameter main body 371Ba towards the inner diameter side, and opens towards the outer diameter side and on both axial sides. In other words, the connecting passage 367B extends axially through the outer diameter side end edge of the large-diameter main body 371Ba. The connecting passage 367B communicates with the back pressure space S33 and the low pressure space S31.

[0254] Furthermore, the outer peripheral surface of the large-diameter main body 371Ba and the inner peripheral surface of the first segment 363 are smooth surfaces with the same diameter throughout the entire axial range, and the two surfaces can slide relative to each other.

[0255] With such a structure, since the outer peripheral surface of the large-diameter main body 371Ba of the pressure drive body 371B moves while sliding in contact with the inner peripheral surface of the first partition 363, although a connecting path 367B is formed between the first partition 363 and the pressure drive body 371B, it is also possible to prevent the pressure drive body 371B from tilting relative to the first partition 363.

[0256] In addition, the force acting on the pressure-sensitive body 361 is roughly the same as that in the aforementioned Example 3.

[0257] Even with such a structure, as described above, since the curved surface 366 of the pressure-sensitive body 361 abuts against the left end face of the small-diameter main body portion 371b of the pressure drive body 371B, it is easy to move along the axis of the pressure-sensitive body 361.

[0258] Alternatively, the connecting path 267B can also be as described in the modified example 2-2 of embodiment 2 above (refer to...). Figure 7 In this way, the gap between the first segment and the pressure driving body is used as a connecting path.

[0259] Example 4

[0260] Next, refer to Figures 11-14 The valve of Example 4 will be described. Furthermore, structural descriptions identical to those in Example 1 will be omitted.

[0261] like Figure 11 As shown, the back pressure control valve V4 in this embodiment 4 is normally open and mainly consists of a housing 460, a valve core 461, and a pressure-sensitive element 462.

[0262] The housing 460 is divided into two low-pressure spaces S41 and S41' communicating with the low-pressure chamber 20, a high-pressure space S42 communicating with the high-pressure chamber 30, and a back-pressure space S43 communicating with the back-pressure chamber 50. Alternatively, the housing 460 may be divided into at least a portion of the low-pressure spaces S41 and S41', the high-pressure space S42, and the back-pressure space S43.

[0263] The housing 460 is composed of a first cylindrical segment 463 and a second cylindrical segment 464.

[0264] A dividing wall portion 463e is formed at the left end of the first dividing body 463, and the dividing wall portion 463e has a through hole 463a.

[0265] A dividing wall portion 463f is formed at the right end of the first dividing body 463, and the dividing wall portion 463f has a through hole 463g.

[0266] The space sandwiched between the partitioned walls 463e and 463f in the axial direction is the high-pressure space S42. The high-pressure space S42 is connected to the high-pressure chamber 30 via a connecting hole 463d formed in the first partition 463.

[0267] Furthermore, the space to the right of the dividing wall portion 463f is a low-pressure space S41' on the other side where the suction fluid Ps flows in. Specifically, the other low-pressure space S41' is divided by the dividing wall portion 463f and the recessed portion of the back pressure control valve V4 provided on the fixed scroll plate 41.

[0268] Furthermore, the dividing wall portion 463e is embedded and fixed within the annular step portion 464b, which is located at the right end opening of the second dividing body 464.

[0269] A dividing wall 464a is formed at the axial center of the second dividing body 464. The dividing wall 464a has a valve hole 464d and a valve seat 465. The valve seat 465 and the tapered surface 466 of the valve core 461 together constitute a valve 470 for opening and closing control of the flow path 468 between the valve seat 465 and the tapered surface 466.

[0270] The space sandwiched between the dividing wall portion 464a of the second dividing body 464 and the dividing wall portion 463e of the first dividing body 463 is a back pressure space S43. The back pressure space S43 communicates with the back pressure chamber 50 through a connecting hole 464c formed in the second dividing body 464.

[0271] A cover component 409 is screwed onto the inner circumferential surface of the left end opening of the second segment 464 in a sealed manner.

[0272] The space sandwiched axially by the dividing wall 464a of the second dividing body 464 and the cover member 409 is a low-pressure space S41. The low-pressure space S41 communicates with the low-pressure chamber 20 via a connecting hole 464e formed in the second dividing body 464.

[0273] A pressure-sensitive element 462 is disposed between the cover component 409 and the valve core 461.

[0274] The pressure-sensitive element 462 consists of a main body 462a and a sealing part 462b. The pressure-sensitive element 462 is a bellows that maintains an internal vacuum. The pressure-sensitive element 462 also functions as a force-applying unit, applying force to the valve core 461 in the opening direction.

[0275] The valve core 461 has a large-diameter main body portion 461a, a medium-diameter main body portion 461b extending axially to the left from the large-diameter main body portion 461a, a small-diameter main body portion 461c protruding further axially to the left from the medium-diameter main body portion 461b with a smaller diameter, and an extension shaft portion 461d extending axially to the right from the large-diameter main body portion 461a.

[0276] The large-diameter main body 461a is inserted through the through hole 463a of the first segment 463.

[0277] The gap between the inner circumferential surface of the dividing wall portion 463e constituting the through hole 463a and the outer circumferential surface of the large-diameter main body portion 461a is extremely small, so the refrigerant hardly moves between the high-pressure space S42 and the back-pressure space S43 through this gap. Furthermore, the inner circumferential surface of the dividing wall portion 463e and the outer circumferential surface of the large-diameter main body portion 461a are smooth surfaces with the same diameter throughout the entire axial range, and the two surfaces can slide relative to each other.

[0278] The intermediate diameter main body 461b has a tapered surface 466 that narrows to the left of the axial direction. The intermediate diameter main body 461b is disposed in the back pressure space S43.

[0279] The small-diameter main body 461c is inserted through the back pressure space S43 side into the valve hole 464d. The end of the small-diameter main body 461c is fitted and connected to the recess 462e formed in the closure part 462b in the low pressure space S41.

[0280] The extension shaft portion 461d is inserted through the through hole 463g. The diameter of the extension shaft portion 461d is larger than the diameter of the middle diameter main body portion 461b.

[0281] The gap between the inner circumferential surface of the dividing wall portion 463f constituting the through hole 463g and the outer circumferential surface of the extending shaft portion 461d is extremely small, so the refrigerant hardly moves between the high-pressure space S42 and the low-pressure space S41' through this gap. Furthermore, the inner circumferential surface of the dividing wall portion 463f and the outer circumferential surface of the extending shaft portion 461d are smooth surfaces with the same diameter throughout the entire axial range, and the two surfaces can slide relative to each other.

[0282] Furthermore, the valve core 461 has a connecting passage 467.

[0283] The cross-sectional shape of the connecting path 467 is formed as an L-shape that flips up and down and flips left and right. The connecting path 467 extends from the left end face of the large diameter main body 461a toward the right side of the axial direction, and extends approximately vertically toward the outer diameter side at a position on the left side of the extension shaft 461d, which is closer to the center of the axial direction.

[0284] The connecting path 467 is configured to always be connected to the high-pressure space S42 and the back-pressure space S43 within the movement range of the valve core 461.

[0285] In the valve core 461, the pressures of the control fluid Pb and the ejected fluid Pd act on the large-diameter main body 461a, the pressures of the control fluid Pb and the suction fluid Ps act on the medium-diameter main body 461b, and the pressure of the suction fluid Ps acts on the extension shaft 461d.

[0286] The effective pressure-bearing surface of the valve core 461, which acts as the back pressure-bearing surface, is approximately the same as the area of ​​the valve seat 465 (C4-A4-E) obtained by subtracting the portion of the flow path cross-section A4 of the valve seat 465 in which the conical surface 466 contacts the valve seat 465 when it is seated on the valve seat 465, which is the portion of the large-diameter main body 461a that is located on the outer side of the flow path cross-section E of the connecting passage 467. Hereinafter, the effective pressure-bearing surface of the valve core 461, which acts as the back pressure-bearing surface, will be referred to as "effective pressure-bearing surface (C4-A4-E)".

[0287] The effective pressure-bearing surface of the valve core 461, which is acted upon by the pressure of the ejected fluid Pd, is approximately the same as the area (C4-B4-E) obtained by subtracting the cross-section B4 of the extension shaft portion 461d from the portion (C4-E) of the cross-section C4 of the large-diameter main body portion 461a that is located on the outer side of the flow path cross-section E of the connecting passage 467. Hereinafter, the effective pressure-bearing surface of the valve core 461 acted upon by the pressure of the ejected fluid Pd will be referred to as "effective pressure-bearing surface (C4-B4-E)".

[0288] The cross section B4 of the extended shaft portion 461d is larger in diameter and wider than the flow path cross section A4 of the valve seat 465 (B4 > A4). As a result, the effective pressure-bearing surface (C4-A4-E) is larger than the effective pressure-bearing surface (C4-B4-E) ((C4-A4-E) > (C4-B4-E)).

[0289] The effective pressure-bearing surface of the valve core 461, which is the low-pressure pressure-bearing surface, is approximately the same as the cross-section B4 of the extended shaft portion 461d, where the pressure of the intake fluid Ps acts. Hereinafter, the effective pressure-bearing surface of the valve core 461, where the pressure of the intake fluid Ps acts, will be referred to as "effective pressure-bearing surface B4".

[0290] Furthermore, regardless of the opening or closing state of valve 470, the closed portion 462b of pressure-sensitive element 462 is always positioned axially to the left, away from the dividing wall portion 464a. That is, the pressure of the suction fluid Ps in the low-pressure space S41 always acts on pressure-sensitive element 462 axially to the left.

[0291] The effective pressure-bearing surface of the pressure-sensitive element 462, which is the low-pressure pressure-bearing surface, is approximately the same as the portion of the effective pressure-bearing surface D4 of the pressure-sensitive element 462 located on the outer side compared to the flow path section A4 of the valve seat 465. Hereinafter, the effective pressure-bearing surface of the pressure-sensitive element 462, which is the pressure of the drawn-in fluid Ps, will be referred to as "effective pressure-bearing surface (D4-A4)".

[0292] Next, the opening and closing operation of the back pressure control valve V4 will be explained. In the housing 460, the suction fluid Ps flows into the low-pressure spaces S41 and S41', the ejection fluid Pd flows into the high-pressure space S42, and the control fluid Pb flows into the back pressure space S43.

[0293] The force (F) generated by the pressure of the fluid Ps drawn into the valve core 461 acting on the effective pressure-bearing surface B4 Ps41 =Ps×B4), the force (F) generated by the pressure of the ejected fluid Pd acting on the effective pressure-bearing surface (C4-B4-E). Pd4 =Pd×(C4-B4-E)) and the force (F) generated by the pressure of the inhaled fluid Ps acting on the effective pressure-bearing surface (D4-A4). Ps42 =Ps×(D4-A4))Press to the left along the axis (i.e., with left as positive, force F41 =F Ps41 +F Pd4 +F Ps42 (Action applied to valve core 461).

[0294] Furthermore, the force (F) generated by the pressure of the controlled fluid Pb acting on the effective pressure-bearing surface (C4-A4-E) of the valve core 461 is... Pb4 =Pb×(C4-A4-E)) and the force of the pressure-sensitive body 462 (F) b4 Press the force F to the right (i.e., with right as positive, force F) along the axis. 42 =F Pb4 +F b4 (Action applied to valve core 461).

[0295] If force F 41 For force F 42 If the above is true, then valve core 461 will move axially to the left, as follows: Figure 12 As shown, it sits on valve seat 465 (F) 41 ≥F 42 That is, valve 470 becomes closed. Furthermore, the closing portion 462b of pressure-sensitive body 462 moves axially to the left as integrally with valve core 461 while the main body portion 462a contracts.

[0296] If force F 41 Below force F 42 Then the valve core 461 moves axially to the right (F 41 <F 42 That is, such as Figure 11 As shown, valve 470 is in the open state. Furthermore, the farther the conical surface 466 of valve core 461 is from valve seat 465, the greater the opening degree of valve 470. Also, in pressure-sensitive body 462, while the main body portion 462a extends, the sealing portion 462b moves axially to the right integrally with valve core 461.

[0297] Regardless of the opening or closing state of valve 470, the ejected fluid Pd flowing from high-pressure space S42 into connecting path 467 is depressurized by throttling and supplied to back-pressure space S43 as control fluid Pb.

[0298] Furthermore, the lubricating oil separated by the oil separator 6, together with the refrigerant, is supplied to the back pressure space S43 through the connecting passage 467.

[0299] With valve 470 open, the control fluid Pb and lubricating oil flowing into the back pressure space S43 through the connecting passage 467 are split into a portion flowing through the connecting hole 464c and a portion flowing through valve 470.

[0300] The control fluid Pb and lubricating oil are supplied to the back pressure chamber 50 through the connecting hole 464c. This increases the pressure of the control fluid Pb in the back pressure chamber 50 and prevents the lubricating oil in the back pressure chamber 50 from drying out.

[0301] Furthermore, the control fluid Pb flowing into valve 470 is depressurized according to the opening degree of valve 470 and provided as suction fluid Ps to a low-pressure space S41. Valve 470 is a so-called BS valve. This prevents excessive pressure rise of the control fluid Pb.

[0302] Furthermore, the lubricating oil flowing into valve 470, along with the refrigerant, is supplied to the low-pressure space S41 through valve 470. This prevents the lubricating oil from drying out in the low-pressure chamber 20.

[0303] When the pressure of the control fluid Pb tends to be insufficient and valve 470 is closed, it is possible to prevent the control fluid Pb from being supplied to the low-pressure space S41 as the intake fluid Ps. On the other hand, the ejected fluid Pd flows into the back-pressure space S43 through the connecting passage 467. As a result, the pressure of the control fluid Pb gradually increases over time.

[0304] As explained above, the back pressure control valve V4 of this embodiment is provided with a connection path 467 that connects the high pressure space S42 and the back pressure space S43. Therefore, the scroll compressor C can be adjusted by using the back pressure control valve V4, which has been adjusted according to the desired specifications. That is, no machining is required on the scroll compressor C side, thus the adjustment of the scroll compressor C can be performed easily.

[0305] Furthermore, within the back pressure control valve V4, lubricating oil can be supplied from the back pressure space S43 to the low pressure space S41 via valve 470. Therefore, compared to a structure that supplies lubricating oil after passing through the back pressure chamber 50 to the low pressure chamber 20, the path of the lubricating oil to the low pressure chamber 20 after separation by the oil separator 6 can be shortened. As a result, lubricating oil depletion in the low pressure chamber 20 can be prevented.

[0306] Furthermore, since the high-pressure space S42 and the back-pressure space S43 are always connected via the connecting passage 467, lubricating oil can be supplied from the high-pressure space S42 to the back-pressure space S43 regardless of the opening or closing state of the valve 470. Therefore, compared to the structure in Embodiment 1 where a valve 70 is provided between the high-pressure space S2 and the back-pressure space S3, it is possible to prevent the lubricating oil in the back-pressure chamber 50 from drying up.

[0307] In addition, in this embodiment, valve 470 is described as a normally open BS valve, but it can also be a normally closed BS valve by employing a force-applying unit that acts in the closing direction.

[0308] Furthermore, since the connecting path 467 is a passageway through the valve core 461, the connecting path 467 can be formed without machining the scroll compressor C.

[0309] Furthermore, the back pressure control valve V4 uses the force (F) generated by the pressure of the ejected fluid Pd. Pd4 ) and the force (F) generated by the pressure of the inhaled fluid Ps. Ps41 +F Ps42 The sum of ) and the force (F) generated by the pressure of the control fluid Pb Pb4 The force (F) of the pressure-sensitive body 462 and the pressure-sensitive body 462 b4 The valve opening is adjusted by balancing the total pressure of the high-pressure chamber 30 and the low-pressure chamber 20, so that the valve opening can be smoothly changed according to the pressure changes of the high-pressure chamber 30 and the low-pressure chamber 20, thereby immediately adjusting the pressure of the back pressure chamber 50.

[0310] Furthermore, in the back pressure control valve V4, the effective pressure-bearing surface B4 affected by the pressure of the intake fluid Ps is larger than the effective pressure-bearing surface (C4-B4-E) affected by the pressure of the ejected fluid Pd (B4 > (C4-B4-E)). Therefore, it is possible to suppress the influence of the ejected fluid Pd pressure, which is relatively higher than the intake fluid Ps pressure, while ensuring that the influence of the intake fluid Ps pressure is relatively large. As a result, it is possible to suppress the rapid movement of the valve core 461 due to the rapid pressure change of the ejected fluid Pd.

[0311] Furthermore, in the back pressure control valve V4, the effective pressure-bearing surface (C4-A4-E) affected by the pressure of the control fluid Pb is larger than the effective pressure-bearing surface (C4-B4-E) affected by the pressure of the ejected fluid Pd ((C4-A4-E) > (C4-B4-E)). Therefore, it is possible to suppress the influence of the ejected fluid Pd pressure, which is relatively higher than that of the control fluid Pb, while ensuring that the influence of the control fluid Pb pressure is relatively large. As a result, it is possible to suppress the rapid movement of the valve core 461 due to the rapid pressure change of the ejected fluid Pd.

[0312] Furthermore, in the back pressure control valve V4, low-pressure spaces S41 and S41' are located at both axial ends of the housing 460, and the pressure of the suction fluid Ps acts on the valve core 461 and the pressure-sensitive element 462, respectively. As a result, the back pressure control valve V4 facilitates the valve core 461 to sit on the valve seat 465.

[0313] Furthermore, in this embodiment, the structure in which the valve core 461 forms a connecting passage 467 has been described, but the modified example 4-1 can also be referred to. Figure 13 The housing 460A has a connecting passage 467A, and the valve core 461A does not have a connecting passage.

[0314] More specifically, the connecting passage 467A axially penetrates the portion of the dividing wall 463Ae of the first dividing body 463A that is closer to the outer diameter than the through hole 463a. The connecting passage 467A is connected to the high-pressure space S42 and the back-pressure space S43.

[0315] The force acting on valve core 461A is explained below. The effective pressure-bearing surface of valve core 461A, which is the back pressure-bearing surface, is (C4-A4) when the pressure of control fluid Pb acts on it.

[0316] The effective pressure-bearing surface of the valve core 461A, which is the high-pressure pressure-bearing surface, is (C4-B4) when the pressure of the ejected fluid Pd acts on it.

[0317] The effective pressure-receiving surface of the valve core 461A, which is the low-pressure receiving surface, is B4, which is acted upon by the pressure of the intake fluid Ps. Furthermore, the effective pressure-receiving surface of the pressure-sensitive element 462, which is the low-pressure receiving surface, is (D4-A4).

[0318] The force (F) generated by the pressure of the fluid Ps drawn into the valve core 461A acting on the effective pressure-bearing surface B4. Ps41 =Ps×B4), the force (F) generated by the pressure of the ejected fluid Pd acting on the effective pressure-bearing surface (C4-B4). Pd41 =Pd×(C4-B4)) and the force (F) generated by the pressure of the inhaled fluid Ps acting on the effective pressure-bearing surface (D4-A4). Ps42 =Ps×(D4-A4))Press to the left along the axis (i.e., with left as positive, force F 43 =F Ps41 +F Pd41 +F Ps42 (Action applied to valve core 461).

[0319] Furthermore, the force (F) generated by the pressure of the controlled fluid Pb acting on the effective pressure-bearing surface (C4-A4) of the valve core 461A is... Pb41 =Pb×(C4-A4))and the force of pressure-sensitive body 462 (F b4 Press the force F to the right (i.e., with right as positive, force F) along the axis. 44 =F Pb41 +F b4 (Action applied to valve core 461).

[0320] Even with this structure, it is possible to form the connecting path 467A without processing the scroll compressor C.

[0321] Furthermore, reference can also be made to the modified example 4-2 shown. Figure 14 A gap is provided between the first segment 463B of the housing 460B and the valve core 461A, and this gap serves as a connecting path 467B that is always connected to the adjacent high pressure space S42 and back pressure space S43.

[0322] More specifically, the diameter of the through hole 463Ba of the first segment 463B, i.e., the inner diameter of the dividing wall portion 463Be, is slightly larger than the diameter of the large-diameter main body portion 461Aa of the valve core 461A. This ensures a radial clearance between the inner circumferential surface of the dividing wall portion 463Be and the outer circumferential surface of the large-diameter main body portion 461Aa.

[0323] In addition, the force acting on the valve core 461A is roughly the same as that in the aforementioned modified example 4-1.

[0324] With such a structure, the connecting path 467B can be easily constructed without modifying the scroll compressor C.

[0325] Furthermore, the connecting path 467B can be easily constructed without the need for machining such as setting a connecting path through the housing 460B and the valve core 461A.

[0326] Example 5

[0327] Next, refer to Figure 15 , Figure 16 The valve of Example 5 will be described. Furthermore, repeated structural descriptions identical to those of Example 1 will be omitted.

[0328] like Figure 15 As shown, the back pressure control valve V5 in this embodiment 5 is normally open and mainly consists of a housing 560, a valve core 561, and a helical spring 562 that applies force to the valve core 561 in the opening direction.

[0329] The housing 560 is divided into a low-pressure space S51 communicating with the low-pressure chamber 20, a high-pressure space S52 communicating with the high-pressure chamber 30, and a back-pressure space S53 communicating with the back-pressure chamber 50. Alternatively, the housing 560 may be divided into at least a portion of the low-pressure space S51, the high-pressure space S52, and the back-pressure space S53.

[0330] The shell 560 is composed of a cylindrical first segment 563 and a cylindrical second segment 564.

[0331] A dividing wall portion 563f is formed on the right side of the first dividing body 563, and the dividing wall portion 563f has a through hole 563g.

[0332] The space to the right of the dividing wall portion 563f is the high-pressure space S52 into which the ejected fluid Pd flows. Specifically, the high-pressure space S52 is divided by the dividing wall portion 563f and the recessed area where the back pressure control valve V5 is installed on the fixed scroll plate 41.

[0333] The first segment 563 is embedded and fixed in the right end opening of the second segment 564.

[0334] A dividing wall portion 564a is formed at the axial center of the second dividing body 564. The dividing wall portion 564a has a valve hole 564d and a valve seat 565. The valve seat 565 and the tapered surface 566 of the valve core 561 together constitute a valve 570 for controlling the opening and closing of the flow path 568 between the valve seat 565 and the tapered surface 566.

[0335] The space sandwiched between the dividing wall portion 564a of the second dividing body 564 and the dividing wall portion 563f of the first dividing body 563 is a low-pressure space S51. The low-pressure space S51 communicates with the low-pressure chamber 20 through a communication hole 564e formed in the second dividing body 564.

[0336] A cover member 509 with a through hole 509a is screwed onto the inner circumferential surface of the left end opening of the second partition 564. The space sandwiched between the dividing wall portion 564a of the second partition 564 and the cover member 509 is a back pressure space S53. The back pressure space S53 communicates with the back pressure chamber 50 via the through hole 509a.

[0337] The valve core 561 has a large-diameter main body portion 561a and an extension shaft portion 561b extending axially to the right from the large-diameter main body portion 561a.

[0338] The large-diameter main body 561a is disposed in the low-pressure space S51. The large-diameter main body 561a is formed with a tapered surface 566 that narrows to the left in the axial direction.

[0339] Furthermore, regardless of the opening or closing state of valve 570, the large-diameter main body 561a is positioned axially to the left, away from the dividing wall 563f. That is, the pressure of the suction fluid Ps in the low-pressure space S51 always acts on the large-diameter main body 561a axially to the left.

[0340] The extended shaft portion 561b is inserted through the through hole 563g.

[0341] The gap between the inner circumferential surface of the dividing wall portion 563f constituting the through hole 563g and the outer circumferential surface of the extending shaft portion 561b is extremely small, so the refrigerant hardly moves between the high-pressure space S52 and the low-pressure space S51 through this gap. Furthermore, the inner circumferential surface of the dividing wall portion 563f and the outer circumferential surface of the extending shaft portion 561b are smooth surfaces with the same diameter throughout the entire axial range, and the two surfaces can slide relative to each other.

[0342] Furthermore, the valve core 561 has a straight connecting passage 567 extending along its axis. The connecting passage 567 connects the high-pressure space S52 with the back-pressure space S53.

[0343] In the valve core 561, the pressures of the control fluid Pb and the suction fluid Ps act on the large-diameter main body 561a, and the pressure of the ejected fluid Pd acts on the extension shaft 561b.

[0344] The effective pressure-bearing surface of the valve core 561, which acts as the back pressure-bearing surface, is approximately the same as the portion (A5-E) of the flow path cross section A5 of the valve seat 565 that contacts the conical surface 566 when it is seated on the valve seat 565, as it is located on the outside of the flow path cross section E of the connecting passage 567. Hereinafter, the effective pressure-bearing surface of the valve core 561 acting on the pressure of the control fluid Pb will be referred to as "effective pressure-bearing surface (A5-E)".

[0345] The effective pressure-bearing surface of the valve core 561, which is the low-pressure pressure-bearing surface, acting under the pressure of the intake fluid Ps is approximately the same as the area (A5-B5) obtained by subtracting the portion (A5-E) of the section B5 of the extension shaft portion 561b that is further outward than the section E of the connecting passage 567 from the portion (A5-E) of the flow path section A5 of the valve seat 565. Hereinafter, the effective pressure-bearing surface of the valve core 561 acting under the pressure of the intake fluid Ps will be referred to as "effective pressure-bearing surface (A5-B5)".

[0346] The effective pressure-bearing surface of the valve core 561, which is the high-pressure pressure-bearing surface, acting under the pressure of the ejected fluid Pd, is approximately the same as the portion (B5-E) of the cross section B5 of the extended shaft portion 561b that is located on the outer side compared to the flow path cross section E of the connecting passage 567. Hereinafter, the effective pressure-bearing surface of the valve core 561 acting under the pressure of the ejected fluid Pd will be referred to as "effective pressure-bearing surface (B5-E)".

[0347] The helical spring 562 is disposed in a compressed state between the cover part 509 and the large-diameter main body 561a of the valve core 561.

[0348] Next, the opening and closing operation of the back pressure control valve V5 will be explained. In the housing 560, the suction fluid Ps flows into the low-pressure space S51, the ejection fluid Pd flows into the high-pressure space S52, and the control fluid Pb flows into the back pressure space S53.

[0349] The force (F) generated by the pressure of the fluid Ps drawn into the valve core 561 acting on the effective pressure-bearing surface (A5-B5) Ps5 =Ps×(A5-B5)) and the force (F) generated by the pressure of the ejected fluid Pd acting on the effective pressure surface (B5-E). Pd5 =Pd×(B5-E))Press to the left along the axis (i.e., with left as positive, force F 51 =F Ps5 +F Pd5 Acting on valve core 561).

[0350] Furthermore, the force (F) generated by the pressure of the controlled fluid Pb acting on the effective pressure-bearing surface (A5-E) of the valve core 561 is... Pb5=Pb×(A5-E))and the force of the helical spring 562 (F b5 Press the force F to the right (i.e., with right as positive, force F) along the axis. 52 =F Pb5 +F b5 Acting on valve core 561).

[0351] If force F 51 For force F 52 The valve core 561 then moves axially to the left and sits on the valve seat 565 (F). 51 ≥F 52 That is, valve 570 becomes closed.

[0352] When force F 51 Below force F 52 At that time, valve core 561 moves axially to the right (F 51 <F 52 That is, valve 570 is in the open state. Furthermore, the farther the conical surface 566 of valve core 561 is from valve seat 565, the greater the opening degree of valve 570.

[0353] Regardless of the opening or closing state of valve 570, the ejected fluid Pd flowing from high-pressure space S52 into connecting path 567 is depressurized by throttling and supplied to back-pressure space S53 as control fluid Pb.

[0354] With valve 570 open, the control fluid Pb flowing into the back pressure space S53 through the connecting passage 567 is split into a portion that flows through the through hole 509a and a portion that flows through valve 570.

[0355] The control fluid Pb is supplied to the back pressure chamber 50 through the through hole 509a. This allows the pressure of the control fluid Pb in the back pressure chamber 50 to be increased.

[0356] Furthermore, the control fluid Pb flowing into valve 570 is depressurized according to the opening degree of valve 570 and provided to the low-pressure space S51 as suction fluid Ps.

[0357] When the pressure of the control fluid Pb tends to be insufficient and valve 570 is closed, it is possible to prevent the control fluid Pb from being supplied to the low-pressure space S51 as the intake fluid Ps. On the other hand, the ejected fluid Pd flows into the back-pressure space S53 through the connecting passage 567. As a result, the pressure of the control fluid Pb gradually increases over time.

[0358] As explained above, the back pressure control valve V5 of this embodiment is provided with a connection path 567 that connects the high pressure space S52 and the back pressure space S53. Therefore, the scroll compressor C can be adjusted by using the back pressure control valve V5, which has been adjusted according to the desired specifications. That is, no machining is required on the scroll compressor C side, thus the adjustment of the scroll compressor C can be performed easily.

[0359] Furthermore, in this embodiment, the structure in which the valve core 561 forms a connecting passage 567 has been described, but the modified example 5-1 can also be referred to. Figure 16 The housing 560A has connecting passages 567Aa and 567Ab, and the valve core 561A does not have connecting passages.

[0360] More specifically, the left end face of the peripheral wall 563Ab of the first segment 563A is pressed into the dividing wall portion 564Aa of the second segment 564A in a sealed manner while being embedded and fixed within the second segment 564A. Furthermore, the seal between the peripheral wall 563Ab and the dividing wall portion 564Aa is not limited to pressing; it can also be achieved using sealing components such as packing seals, and can be modified as appropriate.

[0361] Furthermore, a radially penetrating connecting hole 563Ad is formed on the peripheral wall 563Ab. The connecting hole 563Ad communicates with the connecting hole 564e of the low-pressure space S51 and the second partition 564A.

[0362] Furthermore, an axially extending connecting passage 567Aa is formed on the peripheral wall 563Ab. The connecting passage 567Aa is formed at a position that is different in phase from the connecting hole 563Ad in the circumferential direction. The connecting passage 567Aa is connected to the high-pressure space S52.

[0363] The second segment 564A has a connecting path 567Ab. The connecting path 567Ab extends from the right end face of the dividing wall 564Aa toward the left, and extends axially to the left at the axial center of the dividing wall 564Aa in an inwardly inclined manner. The connecting path 567Ab communicates with the connecting path 567Aa of the first segment 563A and the back pressure space S53.

[0364] The force acting on valve core 561A is described below. The effective pressure-bearing surface of valve core 561A, which acts as the back pressure-bearing surface, is A5, which is the pressure of the control fluid Pb.

[0365] The effective pressure-bearing surface of the valve core 561A, which is the high-pressure pressure-bearing surface, is B5, which is acted upon by the pressure of the ejected fluid Pd.

[0366] The effective pressure-bearing surface of valve core 561A, which is the low-pressure pressure-bearing surface, is (A5-B5) when the pressure of the suction fluid Ps acts on it.

[0367] The force (F) generated when the pressure of the fluid Ps drawn into the valve core 561A acts on the effective pressure-bearing surface (A5-B5) Ps5 =Ps×(A5-B5)) and the force (F) generated by the pressure of the ejected fluid Pd acting on the effective pressure surface B5. Pd51 =Pd×B5) Press to the left along the axis (i.e., with left as positive, force F) 53 =F Ps5 +F Pd51 Acting on valve core 561).

[0368] Furthermore, the force (F) generated by the pressure of the controlled fluid Pb acting on the effective pressure-bearing surface A5 of the valve core 561 is... Pb51 =Pb×A5) and the force of the helical spring 562 (F) b5 Press the force F to the right (i.e., with right as positive, force F) along the axis. 54 =F Pb51 +F b5 Acting on valve core 561).

[0369] Example 6

[0370] Next, refer to Figures 17-19 The valve of Example 6 will be described. Furthermore, repeated structural descriptions identical to those of Example 1 described above will be omitted.

[0371] like Figure 17 As shown, the back pressure control valve V6 in this embodiment 6 is normally open and mainly consists of a housing 660, a valve core 661, and a pressure-sensitive element 662.

[0372] The housing 660 is divided into a low-pressure space S61 communicating with the low-pressure chamber 20, two high-pressure spaces S62 and S62' communicating with the high-pressure chamber 30, and a back-pressure space S63 communicating with the back-pressure chamber 50. Alternatively, the housing 660 may be divided into at least a portion of the low-pressure space S61, the high-pressure spaces S62 and S62', and the back-pressure space S63.

[0373] The shell 660 is composed of a first cylindrical segment 663 and a second cylindrical segment 664.

[0374] A dividing wall portion 663f is formed at the right end of the first dividing body 663, and the dividing wall portion 663f has a through hole 663g.

[0375] The space on the axial right side of the dividing wall 663f is the high-pressure space S62' into which the ejected fluid Pd flows. Specifically, the high-pressure space S62' is divided by the dividing wall 663f and the recessed area where the back pressure control valve V6 is installed on the fixed scroll plate 41.

[0376] The second segment 664 has an annular protrusion 664b protruding axially to the right. The annular protrusion 664b is embedded and fixed in the left opening of the first segment 663.

[0377] In the second segment 664, a valve hole 664a is defined by a peripheral wall 664c that is continuous with the inner diameter side of the left end of the annular protrusion 664b. The corner of the inner diameter side of the right end of the peripheral wall 664c is the valve seat 665. The valve seat 665 and the tapered surface 666 of the valve core 661 together constitute a valve 670 that controls the opening and closing of the flow path 668 between the valve seat 665 and the tapered surface 666.

[0378] The space sandwiched between the peripheral wall 664c of the second partition 664 and the dividing wall 663f of the first partition 663 is a low-pressure space S61. The low-pressure space S61 is connected to the low-pressure chamber 20 via a connecting hole 663d formed in the first partition 663.

[0379] A dividing wall 664f is formed at the axial center of the second dividing body 664, and the dividing wall 664f has a through hole 664g.

[0380] The space enclosed by the dividing wall 664f and the peripheral wall 664c is a back pressure space S63 for controlling the inflow of fluid Pb. The back pressure space S63 is connected to the back pressure chamber 50 via a connecting hole 664e formed in the second dividing body 664.

[0381] A cover component 609 is screwed onto the inner circumferential surface of the left end opening in the second segment 664 in a sealed manner.

[0382] The space sandwiched between the dividing wall 664f of the second dividing body 664 and the cover member 609 is a high-pressure space S62. The high-pressure space S62 is connected to the high-pressure chamber 30 via a connecting hole 664h formed in the second dividing body 664.

[0383] A pressure-sensitive element 662 is disposed between the cover component 609 and the valve core 661.

[0384] The pressure-sensitive element 662 consists of a main body 662a and a sealing part 662b. The pressure-sensitive element 662 is a bellows with an internal vacuum. The pressure-sensitive element 662 also functions as a force-applying unit, applying force to the valve core 661 in the opening direction.

[0385] The valve core 661 has: a large-diameter body portion 661a having a tapered surface 666; a medium-diameter body portion 661b extending axially to the left from the large-diameter body portion 661a; a small-diameter body portion 661c protruding further axially to the left from the medium-diameter body portion 661b; and an extension shaft portion 661d extending axially to the right from the large-diameter body portion 661a.

[0386] The large-diameter main body 661a is disposed in the low-pressure space S61. The large-diameter main body 661a is formed with a tapered surface 666 that narrows to the left in the axial direction.

[0387] Furthermore, regardless of the opening or closing state of valve 670, the large-diameter main body 661a is positioned axially to the left, away from the dividing wall 663f. That is, the pressure of the suction fluid Ps in the low-pressure space S61 always acts on the large-diameter main body 661a axially to the left.

[0388] The middle diameter main body 661b is inserted through the through hole 664g from the back pressure space S63 side.

[0389] The gap between the inner circumferential surface of the dividing wall portion 664f constituting the through hole 664g and the outer circumferential surface of the intermediate diameter main body portion 661b is extremely small, so the refrigerant hardly moves between the high-pressure space S62 and the back-pressure space S63 through this gap. Furthermore, the inner circumferential surface of the dividing wall portion 664f and the outer circumferential surface of the intermediate diameter main body portion 661b are smooth surfaces with the same diameter throughout the entire axial range, and the two surfaces can slide relative to each other.

[0390] The small-diameter main body 661c is fitted and connected to the recess 662e formed in the closed part 662b within the low-pressure space S61.

[0391] The extended shaft portion 661d is inserted through the through hole 663g. The diameter of the extended shaft portion 661d is larger than the diameter of the intermediate diameter main body portion 661b.

[0392] The gap between the inner circumferential surface of the dividing wall portion 663f constituting the through hole 663g and the outer circumferential surface of the extending shaft portion 661d is extremely small, so the refrigerant hardly moves between the high-pressure space S62' and the low-pressure space S61 through this gap. Furthermore, the inner circumferential surface of the dividing wall portion 663f and the outer circumferential surface of the extending shaft portion 661d are smooth surfaces with the same diameter throughout the entire axial range, and the two surfaces can slide relative to each other.

[0393] Furthermore, the valve core 661 has connecting passages 667a and 667b.

[0394] The connecting path 667a is formed in the shape of a U-shaped cross section, extending from the left side of the outer peripheral surface of the middle diameter main body 661b to the inner diameter side, extending approximately vertically to the right side at the radial center of the middle diameter main body 661b, and further extending approximately vertically to the outer diameter side at the axial center of the middle diameter main body 661b.

[0395] The connecting path 667a is configured to always be connected to one of the high-pressure space S62 and the back-pressure space S63 within the movement range of the valve core 661.

[0396] Additionally, regarding the connecting path 667a, it can be formed by creating a connecting path that extends in a straight line from the left end face of the small-diameter main body portion 661c of the valve core 661 toward the axial right side. After connecting this connecting path with each connecting path extending radially, the left side of the connecting path extending in a straight line is closed. Alternatively, it can be formed during valve core manufacturing using an additional processing device, more specifically, a 3D printer as an example. As long as it can be formed, the method can be appropriately modified.

[0397] The connecting path 667b is formed in an L-shaped cross section, extending from the right end face of the extension shaft portion 661d toward the left side of the axial direction, and extending approximately vertically toward the outer diameter side on the right side of the middle diameter main body portion 661b.

[0398] The connecting path 667b is configured to always be connected to the high-pressure space S62' and the back-pressure space S63 of the other party within the range of movement of the valve core 661.

[0399] In the valve core 661, the pressures of the control fluid Pb and the suction fluid Ps act on the large-diameter main body 661a, and the pressure of the ejected fluid Pd acts on the extension shaft 661d.

[0400] The effective pressure-bearing surface of the valve core 661, which acts as the back pressure-bearing surface, is approximately the same as the area of ​​the valve seat 665 in the position where the conical surface 666 contacts the valve seat 665 when it is seated. This area is the portion of the valve seat 665 located on the outer side of the flow path section A6 (A6-E) of the connecting passage 667b, minus the portion of the middle diameter main body portion 661b located on the outer side of the flow path section E of the connecting passage 667a (C6-E). Hereinafter, the effective pressure-bearing surface of the valve core 661 acting on the pressure of the control fluid Pb will be referred to as "effective pressure-bearing surface (A6-C6)".

[0401] The effective pressure-bearing surface of the valve core 661, which is the high-pressure pressure-bearing surface, acting under the pressure of the ejected fluid Pd, is approximately the same as the portion (B6-E) of the cross section B6 of the extended shaft portion 661d that is located on the outer side compared to the flow path cross section E of the connecting passage 667b. Hereinafter, the effective pressure-bearing surface of the valve core 661 acting under the pressure of the ejected fluid Pd will be referred to as "effective pressure-bearing surface (B6-E)".

[0402] The effective pressure-bearing surface of the valve core 661, which is the low-pressure pressure-bearing surface, acting under the pressure of the intake fluid Ps is approximately the same as the area (A6-B6) obtained by subtracting the portion (B6-E) of the section B6 of the extended shaft portion 661d that is located outside the flow path section E of the connecting passage 667b from the portion (A6-E) of the flow path section A6 of the valve seat 665 located outside the flow path section E of the connecting passage 667b. Hereinafter, the effective pressure-bearing surface of the valve core 661 acting under the pressure of the intake fluid Ps will be referred to as "effective pressure-bearing surface (A6-B6)".

[0403] The cross-section B6 of the extended shaft portion 661d is larger and wider in diameter than the cross-section C6 of the small-diameter main body portion 661c (B6 > C6). As a result, the effective pressure-bearing surface (A6-C6) is larger than the effective pressure-bearing surface (A6-B6) ((A6-C6) > (A6-B6)).

[0404] Furthermore, regardless of the opening or closing state of valve 670, the closed portion 662b of pressure-sensitive body 662 is always positioned axially to the left, away from the dividing wall portion 664f. That is, the pressure of the ejected fluid Pd within one of the high-pressure spaces S62 always acts on pressure-sensitive body 662 axially to the left.

[0405] The effective pressure-bearing surface of the pressure-sensitive body 662, which is the high-pressure receiving surface, is approximately the same as the area obtained by subtracting the portion of the cross-section C6 of the middle diameter main body 661b located on the outer side of the flow path cross-section E of the connecting passage 667a (C6-C6+E) from the effective pressure-bearing surface D6 of the pressure-sensitive body 662. Hereinafter, the effective pressure-bearing surface of the pressure-sensitive body 662, which is the pressure-bearing surface of the pressure-sensitive body 662 acting on the pressure of the ejected fluid Pd, will be referred to as "effective pressure-bearing surface (D6-C6+E)".

[0406] Next, the opening and closing operation of the back pressure control valve V6 will be explained. In the housing 660, the suction fluid Ps flows into the low-pressure space S61, the ejection fluid Pd flows into the high-pressure spaces S62 and S62', and the control fluid Pb flows into the back pressure space S63.

[0407] The force (F) generated by the pressure of the fluid Ps drawn into the valve core 661 acting on the effective pressure-bearing surface (A6-B6) Ps6 =Ps×(A6-B6)), the force (F) generated by the pressure of the ejected fluid Pd acting on the effective pressure-bearing surface (B6-E). Pd61 =Pd×(B6-E))and the force (F) generated by the pressure of the ejected fluid Pd acting on the effective pressure-bearing surface (D6-C6+E). Pd62 =Pd×(D6-C6+E))Press to the left along the axis (i.e., with left as positive, force F 61 =F Ps6 +F Pd61 +FPd62 (Action applied to valve core 661).

[0408] Furthermore, the force (F) generated by the pressure of the controlled fluid Pb acting on the effective pressure-bearing surface (A6-C6) of the valve core 661 is... Pb6 =Pb×(A6-C6))and the force of pressure-sensitive body 662 (F b6 Press the force F to the right (i.e., with right as positive, force F) along the axis. 62 =F Pb6 +F b6 (Action applied to valve core 661).

[0409] If force F 61 For force F 62 The valve core 661 then moves axially to the left and sits on the valve seat 665 (F). 61 ≥F 62 That is, valve 670 becomes closed. Furthermore, the closing portion 662b of pressure-sensitive body 662 moves axially to the left as integrally with valve core 661 while the main body portion 662a contracts.

[0410] When force F 61 Below force F 62 At that time, valve core 661 moves axially to the right (F 61 <F 62 That is, valve 670 is in the open state. Furthermore, the farther the conical surface 666 of valve core 661 is from valve seat 665, the greater the opening degree of valve 670. Also, in pressure-sensitive body 662, while the main body 662a extends, the sealing portion 662b moves axially to the right integrally with valve core 661.

[0411] Regardless of the opening or closing state of valve 670, the ejected fluid Pd flowing from the high-pressure space S62 into the connecting passage 667a is depressurized by the throttling effect and supplied to the back pressure space S63 as control fluid Pb.

[0412] Similarly, the ejected fluid Pd flowing from the high-pressure space S62' into the connecting path 667b is depressurized by throttling and supplied to the back pressure space S63 as control fluid Pb.

[0413] With valve 670 open, the control fluid Pb flowing into the back pressure space S63 through connecting passages 667a and 667b is split into a portion flowing through connecting hole 664e and a portion flowing through valve 670.

[0414] The control fluid Pb is supplied to the back pressure chamber 50 through the connecting hole 664e. This allows the pressure of the control fluid Pb in the back pressure chamber 50 to be increased.

[0415] Furthermore, the control fluid Pb flowing into valve 670 is depressurized according to the opening degree of valve 670 and provided to the low-pressure space S61 as suction fluid Ps.

[0416] When the pressure of the control fluid Pb tends to be insufficient and valve 670 is closed, it is possible to prevent the control fluid Pb from being supplied to the low-pressure space S61 as the intake fluid Ps. On the other hand, the ejected fluid Pd flows not only from one high-pressure space S62 into the back-pressure space S63 through the connecting passage 667a, but also from the other high-pressure space S62' into the back-pressure space S63 through the connecting passage 667b. As a result, the pressure of the control fluid Pb can be increased in a shorter time than in the aforementioned embodiment 4.

[0417] As explained above, the back pressure control valve V6 of this embodiment is provided with a connecting passage 667a that connects one high-pressure space S62 to the back pressure space S63 and a connecting passage 667b that connects the other high-pressure space S62' to the back pressure space S63. Therefore, the scroll compressor C can be adjusted by using the back pressure control valve V6, which has been adjusted according to the desired specifications. That is, no machining is required on the scroll compressor C side, thus the adjustment of the scroll compressor C can be performed easily.

[0418] Furthermore, in the back pressure control valve V6, high-pressure spaces S62 and S62' are located at both axial ends of the housing 660, and the pressure of the ejected fluid Pd acts on the valve core 661 and the pressure-sensitive element 662, respectively. As a result, the back pressure control valve V6 facilitates the valve core 661 to sit on the valve seat 665.

[0419] Furthermore, in this embodiment, the structure in which the valve core 661 forms connecting passages 667a and 667b has been described, but the modified example 6-1 can also be referred to. Figure 18 The housing 660A has connecting passages 667Aa, 667Ab, and 667Ac, while the valve core 661A does not have connecting passages.

[0420] More specifically, the connecting path 667Aa axially penetrates the portion of the dividing wall 664Af of the second dividing body 664A that is closer to the outer diameter than the through hole 664g. The connecting path 667Aa is connected to one of the high-pressure spaces S62 and the back-pressure space S63.

[0421] The right end face of the annular protrusion 664Ab of the second segment 664A is pressed into the dividing wall 663Af of the first segment 663A in a sealed manner while it is embedded and fixed in the first segment 663A.

[0422] In addition, the seal between the annular protrusion 664Ab and the dividing wall portion 663Af is not limited to compression sealing; it can also be achieved using sealing components such as packing seals, and can be modified as appropriate.

[0423] Furthermore, the annular protrusion 664Ab is formed with a radially penetrating connecting hole 664Ad. The connecting hole 664Ad communicates with the connecting hole 663d of the first segment 663A.

[0424] The connecting path 667Ab extends axially through the portion of the dividing wall 663Af of the first dividing body 663A that is closer to the outer diameter than the through hole 663g. The connecting path 667Ab is formed at a position that is out of phase with the connecting hole 663d in the circumferential direction. The connecting path 667Ab communicates with the high-pressure space S62' on the other side.

[0425] The connecting path 667Ac extends axially to the left from the right end face of the annular protrusion 664Ab of the second segment 664A. The connecting path 667Ac communicates with the connecting path 667Ab and the connecting hole 664Ae of the first segment 663A.

[0426] The force acting on valve core 661A is described below. The effective pressure-bearing surface of valve core 661A, which is the back pressure-bearing surface, is (A6-C6) when the pressure of control fluid Pb acts on it.

[0427] The effective pressure-receiving surface of the valve core 661A, which is the high-pressure receiving surface, is B6, which is acted upon by the pressure of the ejected fluid Pd. Furthermore, the effective pressure-receiving surface of the pressure-sensitive element 662, which is the high-pressure receiving surface, is (D6-C6), which is acted upon by the pressure of the ejected fluid Pd.

[0428] The effective pressure-bearing surface of the valve core 661A, which is the low-pressure pressure-bearing surface, is (A6-B6) when the pressure of the suction fluid Ps acts on it.

[0429] The force (F) generated by the pressure of the fluid Ps drawn into the valve core 661A acting on the effective pressure-bearing surface (A6-B6) Ps6 =Ps×(A6-B6)), the force (F) generated by the pressure of the ejected fluid Pd acting on the effective pressure-bearing surface B6. Pd63 =Pd×B6) and the force (F) generated by the pressure of the ejected fluid Pd acting on the effective pressure-bearing surface (D6-C6). Pd64 =Pd×(D6-C6))Press to the left along the axis (i.e., with left as positive, force F 63 =F Ps6 +F Pd63 +F Pd64 (Action applied to valve core 661).

[0430] Furthermore, the force (F) generated by the pressure of the controlled fluid Pb acting on the effective pressure-bearing surface (A6-C6) of the valve core 661A is... Pb6 =Pb×(A6-C6))and the force of pressure-sensitive body 662 (F b6 Press the force F to the right (i.e., with right as positive, force F) along the axis. 62=F Pb6 +F b6 (Action applied to valve core 661).

[0431] Furthermore, reference can also be made to the modified example 6-2 shown. Figure 19 A gap is provided between the second segment 664B of the housing 660B and the valve core 661A, and this gap serves as a connecting path 667B that is always connected to the high pressure space S62 and the back pressure space S63 of the adjacent one.

[0432] More specifically, the diameter of the through hole 664Bg of the second segment 664B, i.e. the inner diameter of the dividing wall portion 664Bf, is slightly larger than the diameter of the middle diameter of the main body portion 661Ab of the valve core 661A.

[0433] In addition, the force acting on the valve core 661A is roughly the same as that in the aforementioned modified example 6-1.

[0434] The embodiments of the present invention have been described above with reference to the accompanying drawings. However, the specific structure is not limited to these embodiments, and changes and additions that do not depart from the spirit of the present invention are also included in the present invention.

[0435] For example, in the aforementioned embodiments 1 to 6, a structure was described in which the valve core sits on the valve seat and the valve is closed, i.e., the flow path becomes closed. However, it is not limited to this. It can also be a structure in which the valve core does not sit on the valve seat during the maximum or minimum stroke of the valve core, as long as the valve opening degree is variable.

[0436] Furthermore, in the aforementioned embodiments 1 to 6, the structure in which the force-applying unit is a helical spring or a bellows was described, but it is not limited to this; it can also be a helical wave spring or a leaf spring, and can be modified appropriately. In addition, the structure in which the force-applying unit is a compression spring and functions as a pressing spring was described, but it is not limited to this; it can also be a tension spring. Furthermore, the force-applying unit can also be omitted.

[0437] Furthermore, in the aforementioned embodiments 1 to 6, the back pressure connection was described in the case where only a back pressure connection equipped with a valve was provided, but it is not limited to this. A back pressure connection that connects the high-pressure chamber and the back pressure chamber can also be provided separately. Throttling orifices and valves can also be provided on the separately provided back pressure connection.

[0438] Furthermore, in the aforementioned embodiments 1 to 6, the description focused on a case where only a pressure relief port connecting the valve to the low-pressure chamber was provided. However, this is not the only possibility; a pressure relief port connecting the back-pressure chamber to the low-pressure chamber may also be provided. A throttling orifice or valve may also be provided at the additional pressure relief port.

[0439] Furthermore, in the aforementioned embodiments 1 to 6, the valve of the scroll compressor used in air conditioning systems for automobiles and the like was described, but it is not limited thereto; the valve can also be used to control various working fluids.

[0440] Furthermore, in the aforementioned embodiments 1 to 6, examples of back pressure control valves were described, but for example, it could also be an expansion valve configured between the condenser and evaporator in an air conditioning system, or a capacity control valve assembled in a variable capacity compressor in an air conditioning system.

[0441] Furthermore, the intake fluid, the ejection fluid, and the control fluid can be any of the following states: gas, liquid, or a mixture of gas and liquid.

[0442] Label Explanation

[0443] 60, 60A: Housing; 61, 161, 61A: Valve core; 62: Helical spring (force application unit); 65: Valve seat; 67, 167, 67A: Connecting path; 68: Passage; 260, 260A, 260B: Housing; 261, 261A: Valve core; 262, 262A: Pressure-sensitive element (valve core, force application unit); 265: Valve seat; 267a~267c, 267Aa, 267Ab, 267B: Connecting path; 268: Passage; 360, 360A: Housing; 361: Pressure-sensitive element; 361b: Sealing part (valve core); 362: Helical spring (force application unit); 365: Valve seat; 367, 367A, 367B: Connecting path; 368: Passage; 371, 371A, 371B: Pressure actuator; 372: Disc spring (force application unit); 460, 460A, 460B: Housing; 461, 461A: Valve core; 462: Pressure-sensitive element (force application unit); 465: Valve seat; 467, 467A, 467B: Connecting path; 468: Passage; 560, 560A: Housing; 561, 561A: Valve core; 562: Helical spring (force application unit); 565: Valve seat; 567, 567Aa, 567Ab: Connecting path; 56 8: Passage; 660, 660A, 660B: Housing; 661, 661A: Valve core; 662: Pressure-sensitive element (force application unit); 665: Valve seat; 667a, 667b: Connecting path; 667Aa, 667Ab, 667Ac: Connecting path; 667B: Connecting path; 668: Passage; A1-B1, A2-B2, D3-A3, C4-B4-E, C4-B4, B5-E, B5, B6-E, D6-C6+E, B6, D6-C6: Effective pressure-bearing surface (high-pressure pressure-bearing surface); A1-E, A1, A2-C2, A3, B3b, B3B, C4 -A4-E, C4-A4, A5-E, A5, A6-C6: Effective pressure-bearing surface (back pressure-bearing surface); B1-E, B1, B2-E, D2-C2, B2, B3s, B3S, B4, D4-A4, A5-B5, A6-B6: Effective pressure-bearing surface (low pressure-bearing surface); S1, S21, S21', S31, S41, S41', S51, S61: Low pressure space; S2, S22, S32, S42, S52, S62, S62': High pressure space; S3, S23, S33, S43, S53, S63: Back pressure space; V1~V6: Back pressure control valve.

Claims

1. A valve having: A housing having a high-pressure space for the inflow of high-pressure fluid, a back-pressure space for the inflow of back-pressure fluid, a low-pressure space for the inflow of low-pressure fluid, and a passageway disposed between the high-pressure space and the back-pressure space; and The valve core has a high-pressure receiving surface located in the high-pressure space, a back-pressure receiving surface located in the back-pressure space, and a low-pressure receiving surface located in the low-pressure space. This valve core controls the opening degree of the passage. in, The valve is provided with a connection path that connects the back pressure space and the low pressure space.

2. The valve according to claim 1, wherein, The connecting path is a passageway that runs through the valve core.

3. The valve according to claim 1, wherein, The connecting path is a passageway that runs through the housing.

4. The valve according to claim 1, wherein, The back pressure space is arranged adjacent to the low pressure space. The connecting passage is located between the housing and the valve core.

5. The valve according to claim 4, wherein, The connecting path is the radial gap between the housing and the valve core, and it is always connected to the back pressure space and the low pressure space.

6. A valve having: A housing having a high-pressure space for the inflow of high-pressure fluid, a back-pressure space for the inflow of back-pressure fluid, a low-pressure space for the inflow of low-pressure fluid, and a passage disposed between the back-pressure space and the low-pressure space; and The valve core has a high-pressure receiving surface located in the high-pressure space, a back-pressure receiving surface located in the back-pressure space, and a low-pressure receiving surface located in the low-pressure space. This valve core controls the opening degree of the passage. in, The valve is provided with a connecting passage that connects the high-pressure space and the back-pressure space.

7. The valve according to claim 6, wherein, The connecting path is a passageway that runs through the housing.

8. The valve according to claim 6, wherein, The connecting path is a passageway that runs through the valve core.

9. The valve according to claim 6, wherein, The high-pressure space and the back-pressure space are arranged adjacent to each other. The connecting passage is located between the housing and the valve core.

10. The valve according to claim 9, wherein, The connecting path is the radial gap between the housing and the valve core, and it is always connected to the high-pressure space and the back-pressure space.

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