Compressor safety valve

Abstract

[Problem] To provide a compressor safety valve that regulates an exhaust gas jetting direction by attaching a cover to a valve body through an elastic body, and thereby eliminates the inconvenience of exhaust gas jetting out from a gap in the cover, and that is easy to assemble without the need of using a complex-shaped elastic body, nor requiring orientation when mounting the elastic body. [Solution] A compressor safety valve comprises: a columnar valve body 2 including an internal passage 5 for circulating exhaust gas, a second end portion 9 at which an outlet 8 of the internal passage 5 is open, and a fitting portion 10 formed on an outer peripheral surface; a cover 3 including leg portions 31a to 31d that fit with the fitting portion 10 of the valve body 2, and a shielding portion 32 that faces the second end portion 9; and an O-ring 4 that is interposed between the second end portion 9 of the valve body 2 and the shielding portion 32 of the cover 3 so as to surround the outlet 8. The shielding portion 32 has a groove portion 33 formed from a location facing the inside of the O-ring 4 to an outer edge of the shielding portion 32. This groove portion 33 provides communication between the inside and outside of the O-ring 4, and regulates the exhaust gas jetting direction.

Description

【Technical Field】 【0001】 The present invention relates to a safety valve for a compressor used in a refrigeration cycle of a vehicle or the like. 【Background Art】 【0002】 In the engine room of a vehicle, a compressor used in a refrigeration cycle for an air conditioner is disposed. This compressor includes a safety valve. This safety valve releases the exhaust gas containing lubricating oil and refrigerant gas to the outside when the pressure inside the compressor abnormally rises. For example, in the compressor 100 shown in FIG. 10, the safety valve 1 is installed on the side of the cylinder head 100a with the jet outlet facing the pulley 100b side, and when the pressure inside the compressor abnormally rises, the high-pressure exhaust gas from inside the compressor is ejected forward (pulley side) of the compressor. 【0003】 However, when the lubricating oil in the exhaust gas ejected from the safety valve 1 is sprayed onto the high-temperature components in the engine room, there is a concern about the risk of smoking or ignition. Further, as shown in FIG. 9, when the exhaust gas is ejected toward the pulley that holds the drive belt for transmitting power from the engine, the lubricating oil in the exhaust gas causes the drive belt and the electromagnetic clutch to slip. Therefore, there is a concern about the inconvenience of preventing power transmission to the auxiliary machines including the compressor. 【0004】 Therefore, in order to avoid the inconvenience that the exhaust gas ejected from the valve body is ejected in an unintended direction, a safety valve as shown in Patent Document 1 has been considered. As shown in Figure 11, this comprises a cover 102 that is detachably attached to the valve body 101, and an elastic body 103 that covers the discharge hole 101a of the valve body 101, is in close contact with the valve body 101, and is sandwiched between the valve body 101 and the cover 102 in a compressed state. A groove 104 is formed on the contact surface of the elastic body 103 that is in close contact with the valve body 101, from the portion facing the discharge hole 101a to the outer edge. The groove 104 and the surface of the valve body 101 that covers the groove 104 provide a discharge gas passage 105 that ejects the exhaust gas discharged from the discharge hole 101a toward the outer edge where the groove 104 opens. 【0005】 Here, as shown in Figure 11(c), the cover 102 is formed from a plate material having a hexagonal shielding portion 102a and legs 102b and 102c that project radially from five sides of the shielding portion 102a, excluding one side corresponding to the outer edge where the groove 104 of the elastic body 103 opens. Each leg 102b and 102c is manufactured by bending them at approximately right angles along each side of the shielding portion 102a. A locking claw 102d formed on the leg 102b is designed to lock onto a locking projection 101b of the valve body 101. 【0006】 Therefore, gaps (slits) are formed between adjacent legs in the circumferential direction of the cover, extending from the shielding portion. However, since an elastic body 103 with a groove 104 formed from the portion facing the discharge hole 101a to the outer edge is interposed between the cover 102 and the valve body 101, the exhaust gas discharged from the discharge hole 101a is ejected only from the outer edge portion where the groove 104 of the elastic body 103 is open. Therefore, it is possible to avoid the inconvenience of the gas being ejected in an unintended direction through the aforementioned gaps (slits). [Prior art documents] [Patent Documents] 【0007】 [Patent Document 1] Japanese Patent Application Publication No. 9-166081 [Overview of the Initiative] [Problems that the invention aims to solve] 【0008】 However, conventionally, a groove 104 forming the discharge gas passage 105 was formed in an elastic body 103 sandwiched between the shielding portion 102a of the cover 102 and the end face of the valve body 101. This resulted in a complex shape for the elastic body, raising concerns about increased manufacturing costs. Furthermore, when attaching the cover 102 to the valve body 101, the orientation of the outer edge where the groove 104 of the elastic body 103 opens must be aligned with the portion of the cover 102 that does not have legs. This requires careful attention to the assembly direction of the elastic body, making the assembly process of the safety valve complicated. 【0009】 This invention has been made in view of the above circumstances, and its main objective is to provide a safety valve for a compressor that eliminates the inconvenience of exhaust gas being ejected from gaps even when gaps are formed in the cover, does not require the use of elastic bodies with complex shapes, and furthermore, does not require any orientation of the elastic body during assembly, making it easy to assemble. [Means for solving the problem] 【0010】 To achieve the above objectives, the safety valve for the compressor according to the present invention firstly A safety valve for a compressor that discharges exhaust gas to the outside when the internal pressure of the compressor rises above a predetermined pressure, A columnar valve body comprising an internal passage through which exhaust gas flows, a first end with an open inlet for the internal passage, a second end with an open outlet for the internal passage, and a fitting portion formed on its outer surface, A cover comprising a leg portion that fits into the fitting portion of the valve body and a shielding portion that faces the second end, The valve comprises an annular elastic body sandwiched between the second end of the valve body and the shielding portion of the cover, so as to surround the outlet, The shielding portion extends from the part facing the inside of the elastic body to the outer edge of the shielding portion. The second end was bulged out so as to move away from it. A groove is formed 、 The groove is configured to form a passage between itself and the valve body for guiding the exhaust gas to the outside. It is characterized by the fact that... 【0011】 Therefore, an elastic body is sandwiched between the second end and the shielding portion so as to surround the outlet of the internal passage of the valve body. A groove is formed in the shielding portion from the part facing the inside of the elastic body to the outer edge, so that the inside and outside of the elastic body are in communication through this groove, and a discharge passage is formed for the exhaust gas discharged from the outlet to be ejected to the outside. For this reason, the elastic body sandwiched between the second end and the shielding portion does not need to have a complex shape as long as it is an annular shape that surrounds the outlet. 【0012】 Furthermore, since an annular elastic body is sandwiched between the second end of the valve body and the shielding portion so as to surround the outlet, even if a gap is formed between the legs on the radially outer side of the elastic body or between the shielding portion and the legs, there is no inconvenience of exhaust gas leaking from anywhere other than the groove. Furthermore, if the elastic body is an annular shape, the groove can connect the inner and outer parts of the elastic body of the shielding portion, regardless of where the part facing the groove is located in the circumferential direction. Therefore, since the inner and outer parts of the elastic body are connected only by the groove formed in the shielding portion, there is no directionality required for assembling the elastic body, making assembly easier. 【0013】 Herein, secondly, preferably, the safety valve of the compressor described in the first, wherein the elastic body is in close contact with the contact surface of the second end of the valve body over its entire circumference, and is in close contact with the shielding portion of the cover, except for the portion facing the groove. Even when gaps (slits) are provided between adjacent legs, or when a gap is formed between a leg and a shielding portion, the elastic body is in close contact with the shielding portion except for the portion where the contact surface of the second end of the valve body faces the groove. Therefore, exhaust gas is ejected only from the groove, eliminating the inconvenience of exhaust gas leaking through the gaps (slits). 【0014】 Thirdly, preferably, the safety valve of the compressor described in the first or second, wherein the elastic body can be of any shape as long as it is annular, but it is preferable to use a versatile elastic body such as an O-ring. By using O-rings as elastic bodies, there is no need to perform any special processing on the elastic bodies, and since there is no directional requirement for assembling the elastic bodies, assembly becomes easier. 【0015】 Fourth, preferably, in the safety valve of the compressor described in the first to third, a boss portion having an outer diameter smaller than the inner diameter of the elastic body is formed protruding from the contact surface of the valve body, and the elastic body is arranged around the boss portion provided on the contact surface of the valve body. With this configuration, the elastic body is positioned around the boss portion, making it easy and reliable to position the elastic body. Furthermore, when high-pressure exhaust gas is blown out from the outlet, the problem of the elastic body being pulled out through the radial opening due to the pressure of the high-pressure exhaust gas is eliminated. 【0016】 Furthermore, fifthly, preferably in the safety valve of the compressor described in the first to third, the cover may have a radial opening formed adjacent to the groove on the outer edge of the shielding portion, and a restricting portion for restricting the radial movement of the elastic body may be provided in the radial opening. Even if a boss portion is not formed on the contact surface of the valve body, and a radial opening wider than the outer diameter of the elastic body is formed in the cover, a restricting portion is provided in the radial opening to restrict the radial movement of the elastic body. This makes it possible to avoid the inconvenience of the elastic body shifting radially and escaping through the radial opening when high-pressure exhaust gas is blown out from the outlet. 【0017】 Herein, sixth, preferably the safety valve of the compressor described in fifth, wherein the width of the radial opening is formed to be narrower than the outer diameter of the elastic body by the regulating portion. Herein, seventh, preferably the safety valve of the compressor described in sixth, the regulating portion may be formed by a protruding piece projecting radially from the leg portion to the opening. According to such a configuration, the width of the radial opening is narrowed by the restricting portion, so that when the high-pressure exhaust gas blows out from the discharge hole, it is possible to prevent the inconvenience that the elastic body is displaced in the radial direction and escapes from the radial opening. 【0018】 Further, eighthly, preferably a safety valve of the compressor according to the sixth description, wherein the restricting portion may be formed by a leg portion adjacent to the radial opening. That is, the movement of the elastic body in the radial direction may be restricted by making the distance between the leg portions on both sides of the radial opening smaller than the outer diameter of the elastic body. According to such a configuration, since the restricting portion is formed by the leg portion, there is no need to add a new configuration for restricting the radial movement of the elastic body. 【0019】 In addition, ninthly, preferably a safety valve of the compressor according to the first to seventh descriptions, wherein a plurality of leg portions are formed in the circumferential direction of the shielding portion, and each of the leg portions may be integrally formed on the outer edge of the shielding portion. Further, tenthly, preferably a safety valve of the compressor according to the first to seventh descriptions, wherein a plurality of leg portions are formed in the circumferential direction of the shielding portion, one of the leg portions is integrally formed on the outer edge of the shielding portion, and starting from this leg portion, the other leg portions are connected along the circumferential direction of the shielding portion so that all the leg portions are integrally formed. 【Advantages of the Invention】 【0020】 As described above, according to the safety valve of the compressor according to the present invention, an annular elastic body is sandwiched between the second end portion and the shielding portion so as to surround the outlet of the internal passage of the valve body, and a groove portion is formed from the portion facing the inside of the elastic body of the shielding portion to the outer edge to form a discharge passage for the exhaust gas. Therefore, the exhaust gas is not ejected from the gaps or slits formed between the leg portions of the cover or between the shielding plate and the leg portions. In addition, there is no need to use an elastic body with a complicated shape, and during assembly, it is only necessary to adjust the opening position of the groove portion so as to obtain a desired injection direction and then attach the cover. Therefore, the assembly can be easily performed. [Brief explanation of the drawing] 【0021】 [Figure 1] Figure 1 shows a first embodiment of a compressor safety valve according to the present invention, where (a) is a front view thereof, and (b) is a view from direction A. (b) is a side view of the safety valve of (a) from direction B. (c) is a perspective view from an intermediate angle between (a) and (b). [Figure 2] Figure 2 is an exploded perspective view of the safety valve of the compressor according to the first embodiment. [Figure 3] Figure 3 is a cross-sectional view of the safety valve of the compressor according to the first embodiment, where (a) is a cross-sectional view along the line AA-AA in Figure 1(b), and (b) is a cross-sectional view of the safety valve in Figure 1(a) along the line BB-BB. [Figure 4] Figure 4(a) shows the end face of the second end of the valve body, Figure 4(b) shows the state in which an annular elastic body (O-ring) is arranged around the boss portion of the end face of the second end of the valve body, Figure 4(c) shows the inside of the cover, and Figure 4(d) shows the state in which an annular elastic body (O-ring) is arranged inside the cover. [Figure 5] Figure 5(a) is a perspective view of an example of a cover seen from the opposite side of the radial opening, and Figure 5(b) is a perspective view of another example of a cover seen from the opposite side of the radial opening. [Figure 6] Figure 6 shows a second embodiment of the compressor safety valve according to the present invention, where (a) is a front view thereof, and (b) is a view from direction C. (b) is a side view of the safety valve of (a) from direction D. (c) is a perspective view from an intermediate angle between (a) and (b). [Figure 7] Figure 7 is an exploded perspective view of the safety valve of the compressor according to the second embodiment. [Figure 8] Figure 8 is a cross-sectional view of the safety valve of a compressor according to the second embodiment, where (a) is a cross-sectional view along the CC-CC line in Figure 6(b), and (b) is a cross-sectional view along the DD-DD line in Figure 6(a). [Figure 9]Figure 9 shows another example of the cover, where (a) is its top view, (b) is its rear view, (c) is its front view, (d) is its right side view, (e) is its bottom view, and (f) is its perspective view. [Figure 10] Figure 10 shows an example of a compressor with a safety valve installed. [Figure 11] Figure 11 shows a conventional safety valve, where (a) is a perspective view thereof, (b) is a cross-sectional view along the EE-EE line in (a), (c) is an unfolded view of the cover, and (d) is a perspective view of the elastic body. [Best Mode for Carrying Out the Invention] 【0022】 Embodiments of the present invention will be described below with reference to the accompanying drawings. 【0023】 Figures 1 to 3 show a first embodiment of the safety valve 1 according to the present invention. The safety valve 1 comprises a valve body 2 fixed to the compressor housing by screws, a cover 3 attached to the gas outlet end of the valve body 2 (the tip of the valve body protruding from the compressor housing), and an O-ring 4, which is an annular elastic body interposed between the valve body 2 and the cover 3. 【0024】 The valve body 2 is formed in a columnar shape and has an internal passage 5 formed axially on its axis for circulating exhaust gas, a first end 7 through which the inlet 6 of the internal passage 5 opens, a threaded portion 21 on the outer circumferential surface of the first end 7 that screws into the housing, a second end 9 through which the outlet 8 of the internal passage 5 opens, and a fitting portion 10 formed on the outer circumferential surface of the second end 9. 【0025】 Furthermore, a valve body housing space 11 is formed inside the valve body 2, midway through the internal passage 5. The valve body housing space 11 houses a valve body 13 that is axially displaceable and opens and closes an inlet passage 12 connecting the discharge chamber of the compressor (not shown) and the valve body housing space 11, a biasing member 14 consisting of a compression spring that biases the valve body 13 in the direction of closing the inlet passage 12, and a cover (spring receiver) 15 provided at the outlet 8 to close the valve body housing space 11 and to receive the biasing member (compression spring) 14 positioned between the valve body 13 and the outlet 8. The inner diameter of the outlet 8 is larger than that of the valve body housing space 11, and the cover (spring receiver) 15 is fitted into the outlet 8 to close the valve body housing space 11. An outlet passage 16 is formed in the center of the cover (spring receiver) 15, connecting the valve body housing space 11 and the outside of the valve body 2. 【0026】 The fitting portion 10 is constructed by forming an annular groove 18 in the approximate center of the side surface of the head 17 of the valve body 2, which is formed in a hexagonal cross-section with a predetermined width in the axial direction from the second end 9. In other words, the fitting portion 10 has an annular groove 18 formed in the approximate center of the outer circumferential surface of the head 17 in the axial direction, having an inner diameter smaller than the distance between the axis of the valve body 2 and the outer surface of the head 17, and the outflow side surface of this annular groove 18, which is approximately perpendicular to the axis, serves as a locking surface 18a, enabling the claws 311a to 311d of the legs 31a to 31d of the cover 3, which will be described later, to engage and lock in the axial direction. 【0027】 Furthermore, as shown in Figures 4(a) and 4(b), an annular boss portion 19 centered on the axis and projecting in the axial direction is integrally formed on the second end portion 9, and a contact surface 9a for contacting the O-ring 4 is formed around the entire circumference of this boss portion 19. This O-ring 4 is a well-known material made of an elastic material such as nitrile rubber, silicone rubber, EPDM, or soft resin. 【0028】 The inner diameter of this boss portion 19 is formed to be larger than the inner diameter of the valve body housing space 11, and is formed to be approximately equal to the outer diameter of the cover 15. Furthermore, the outer diameter of the boss portion 19 is formed to be approximately equal to the inner diameter of the O-ring 4. Therefore, when the O-ring 4 is fitted around the boss portion 19, the O-ring 4 is positioned and prevented from moving radially. 【0029】 The cover 3, described below, is attached to the second end 9 of the valve body 2 via an O-ring 4. The cover 3 is formed by processing a plate-shaped metal material. As shown in Figures 4(c), (d) and 5(a), the cover 3 has leg portions 31a, 31b, 31c, and 31d that fit into the fitting portion 10 of the valve body 2, and a shielding portion 32 that faces the second end portion 9 in the axial direction. 【0030】 The shielding portion 32 is formed in a roughly hexagonal shape to match the cross-sectional shape of the head 17 of the valve body 2. The legs 31a, 31b, 31c, and 31d are formed by bending each of the four sides of the outer periphery of the shielding portion 32, excluding two adjacent sides. That is, legs 31a to 31d are provided on each of the four sides of the outer periphery of the shielding portion 32, extending radially outward, and these legs 31a to 31d are formed by bending them at roughly right angles to the shielding portion 32. As a result, gaps (slits) S are formed between adjacent legs in the circumferential direction that are formed by bending (between leg 31a and leg 31b, between leg 31b and leg 31c, and between leg 31c and leg 31d). Furthermore, at the tip of each leg portion 31a to 31d, claw portions 311a to 311d are formed such that they can be locked onto the locking surface 18a of the annular groove 18, causing the tip of the leg portion to curve inward. The length of the legs 31a to 31d (the distance between the shielding portion 32 and the tip of the claw portion) is set to such a length that the claw portions 311a to 311d of the legs 31a to 31d are locked to the fitting portion (locking surface 18a of the annular groove 18) when the O-ring 4 is interposed between the shielding portion 32 and the valve body 2 and compressed. 【0031】 Furthermore, the shielding portion 32 has a radially extending groove 33 that is recessed from the part facing the inside of the O-ring 4 to the outer edge of the shielding portion 32. That is, the groove 33 is formed by bulging a part of the shielding portion 32 away from the second end 9, from the middle of the shielding portion 32 to two sides of the outer edge of the shielding portion 32 where the legs 31a to 31d are not provided. Consequently, a radial opening 34 without legs is formed on the outer circumferential surface of the cover 3 over a central angle range of approximately 120 degrees, and this radial opening 34 is formed to overlap with the groove 33. The width between the pair of radially opposing legs of the cover 3 (the distance between leg 31a and leg 31d) is formed to be approximately equal to the outer diameter of the O-ring 4, and the width of the groove 33 is smaller than the width between the pair of radially opposing legs and is formed to be approximately equal to the inner diameter of the O-ring 4. 【0032】 Therefore, a U-shaped contact surface 3a is formed around the groove 33 of the shielding portion 32 of the cover 3, that is, between the groove 33 and the respective legs 31a to 31d, to which the O-ring 4 abuts (see Figure 4(c)), so that the O-ring 4 does not abut the cover 3 within a range of approximately 120 degrees in central angle. Furthermore, the radial opening 34 is formed by not providing legs on two adjacent sides of the shielding portion 32, so it is formed to have a width approximately equal to the distance between a pair of radially opposing legs, that is, a width approximately equal to the outer diameter of the O-ring 4. 【0033】 Therefore, when the O-ring 4 is placed around the boss portion 19 of the second end portion 9 of the valve body 2, and the cover 3 is assembled to the second end portion of the valve body 2 from the axial direction, the O-ring 4 is held in close contact between the contact surface 9a around the boss portion 19 of the second end portion 9 and the U-shaped contact surface 3a around the groove portion 33 of the cover 3. When the claw portions 311a to 322d of the legs 31a to 31d are engaged with the locking surface 18a of the annular groove 18 which is the fitting portion 10, and the cover 3 is fitted onto the head portion 17 of the valve body 2, the O-ring 4 is compressed and held in place between the second end portion 9 of the valve body 2 and the shielding portion 32. 【0034】 Furthermore, a gas discharge passage 36 is formed by the gap between the groove 33 formed in the shielding portion 32 and the end face of the second end portion 9 and the O-ring 4, which connects the inside and outside of the O-ring 4. Therefore, when the internal pressure of the compressor becomes abnormally high, the valve body 13 of the safety valve 1 lifts, and high-pressure exhaust gas is discharged from the outlet 8 (outlet side passage 16) through the valve body housing space 11. As shown in Figures 3(b) and 4(d), the discharged exhaust gas collides with the shielding part 32, changes direction by 90 degrees, flows along the groove 33, and is ejected outside the compressor through the gap between the O-ring 4 and the groove 33, via the groove 33 and the radial opening 34. 【0035】 Therefore, according to the above configuration, the gap (slit) S between each leg is located radially outward from the O-ring 4. Consequently, since the space between the shielding portion 32 and the second end portion 9 is sealed by the O-ring 4 inside the gap (slit) S between the legs, exhaust gas is not guided into the gap (slit) S between the legs, and the inconvenience of exhaust gas being ejected from the gap (slit) S can be avoided. Furthermore, since a general-purpose annular elastic body such as an O-ring 4 can be used as the elastic body interposed between the valve body 2 and the cover 3, there is no need to use an elastic body with a complex shape, and it is possible to avoid the complexity and increased manufacturing costs associated with molding the elastic body. Furthermore, by setting the opening direction of the groove 33 and radial opening 34 of the cover 3 to any desired direction, the direction of ejection of the high-pressure exhaust gas can be set to any desired direction, making it possible to easily assemble the product to achieve the desired ejection direction during assembly. 【0036】 Furthermore, in the above example, a boss portion 19 is provided at the second end 9 of the valve body 2, and an O-ring 4 is arranged around it. This makes it possible to avoid the inconvenience of the O-ring 4 moving radially and coming out of the radial opening 34 when the safety valve 1 is activated and high-pressure exhaust gas is ejected from the outlet passage 16, changes direction, and is discharged along the groove portion 33. 【0037】 In the above example, as shown in Figure 5(a), the legs 31a, 31b, 31c, and 31d extending radially outward from each of the four sides of the shielding portion 32 are bent at approximately 90 degrees relative to the shielding portion 32, thereby integrally forming multiple legs 31a to 31d on the outer edge of the shielding portion 32. In addition to the above example, as shown in Figure 5(b), in the case of multiple legs 31a to 31d formed in the circumferential direction of the shielding portion 32, only one of the legs 31a may be integrally formed extending radially outward from the outer edge of the shielding portion 32, and the other legs 31b, 31c, and 31d may be connected along the circumferential direction of the shielding portion 32 starting from this leg 31a, thereby integrally forming all the legs 31a to 31d. 【0038】 Figures 6 to 8 show a second embodiment of the compressor's safety valve 1. In this example, the valve body 2 differs from the configuration in Figures 1 to 3 in that a boss portion 19 is not formed on the second end portion 9. 【0039】 In this example, as shown in Figure 5(b), the cover 3 has only one leg portion, a leg portion 31a, which extends radially outward from the outer edge of the shielding portion 32, and the other legs portions 31b, 31c, and 31d are connected along the circumferential direction of the shielding portion 32, with this leg portion 31a as the starting point, so that all the legs 31a to 31d are formed integrally. However, restricting portions 35a and 35b are provided in the radial opening 34 to restrict the radial movement of the O-ring 4. These restricting portions 35a and 35b are formed by protruding pieces extending from the leg portions 31a and 31d into the radial opening 34, and the effective width of the radial opening 34 (the width between the restricting portions 35a and 35b) is formed to be substantially narrower than the outer diameter of the O-ring 4. In this example, we have shown a case where one of the multiple leg portions 31a to 31d connected along the circumferential direction is formed integrally with the shielding portion 32, but any of the other leg portions 31b, 31c, or 31d may also be formed integrally with the shielding portion 32. Other components are the same as in the first embodiment, so the same reference numerals are used for the same parts and their descriptions are omitted. 【0040】 Therefore, in the second embodiment, since the valve body 2 does not have a boss portion 19 that restricts the radial movement of the O-ring 4, if there are no restricting portions 35a and 35b, there is a concern that the O-ring 4 will move radially due to the high-pressure gas ejected from the outlet 8 and be pushed out from the radial opening 34. However, since the restricting portions 35a and 35b are provided protruding from the legs 31a and 31d into the radial opening 34, and the width of the radial opening 34 is made narrower than the outer diameter of the O-ring 4 (the width between the restricting portions 35a and 35b is made smaller than the outer diameter of the O-ring 4), it is possible to avoid the inconvenience of the O-ring 4 being pushed out from the radial opening 34. 【0041】 Furthermore, even in a configuration where multiple legs are integrally formed on the outer edge of the shielding portion 32 by bending the legs 31a, 31b, 31c, and 31d extending radially outward from each of the four sides of the shielding portion 32 at approximately 90 degrees relative to the shielding portion 32, as shown in Figure 5(a), the restricting portions 35a and 35b can be formed by projecting them from the legs 31a and 31d into the radial opening 34. 【0042】 Therefore, in this configuration as well, similar to the above embodiment, when the internal pressure of the compressor becomes abnormally high, the valve body 13 of the safety valve 1 lifts, and the high-pressure exhaust gas is discharged from the outlet 8 (outlet side passage 16) through the valve body housing space 11, the discharged exhaust gas collides with the shielding portion 32, its direction is changed by 90 degrees, it flows along the groove portion 33, and is released from the safety valve 1 through the gap between the O-ring 4 and the groove portion 33. 【0043】 A gap (slit) S is formed between the legs 31b to 31d of the cover 3 and the shielding portion 32, but this gap is located radially outward from the O-ring 4. Therefore, the space between the shielding portion 32 of the cover 3 and the second end portion 9 of the valve body 2 is sealed by the O-ring 4 in front of the gap (slit) S, making it possible to avoid the inconvenience of exhaust gas being ejected from the gap (slit) S. Furthermore, since a general-purpose elastic material such as an O-ring 4 is used as the elastic body interposed between the valve body 2 and the cover 3, there is no need to use an elastic body with a complex shape, thus avoiding the complexity and cost increase associated with the molding of the elastic body. Furthermore, by setting the opening direction of the groove 33 and radial opening 34 of the cover 3 to any desired direction, the direction of ejection of the high-pressure exhaust gas can be arbitrarily changed, making it possible to easily assemble the product to achieve the desired ejection direction during assembly. 【0044】 In the above embodiment, an example was described in which an O-ring 4 was used as the annular elastic body. However, other shapes of elastic bodies may be used as long as they are sandwiched between the second end 9 of the valve body 2 and the shielding portion 32 of the cover 3, making close contact with the end face of the second end of the valve body 2 over its entire circumference, and making close contact with the shielding portion 32 of the cover 3 except for the portion facing the groove portion 33. Furthermore, although the above-described configuration explains an example in which cover 3 is formed by processing a metal plate, it is possible to obtain the same effects by forming a similar cover from a resin material. 【0045】 Furthermore, in the above-described configuration, an example was shown in which, in a cover 3 having a shielding portion 32 that is approximately hexagonal in plan view, legs are not provided on two adjacent sides of the shielding portion 32, a radial opening 34 is formed on the outer circumferential surface of the cover 3 over a central angle range of approximately 120 degrees, and the groove portion 33 is extended to the two outer edges of the shielding portion 32 where the legs 31a to 31d are not provided (see Figures 4(c), (d), etc.). However, as shown in Figure 9, a leg may be not provided on only one side of the shielding portion 32 of the cover 3, a radial opening 34 is formed on the outer circumferential surface of the cover 3 over a central angle range of approximately 60 degrees, and the groove portion 33 is extended to the outer edge of this shielding portion 32 where the leg portion is not provided. 【0046】 The cover 3 shown in Figure 9 illustrates an example in which multiple legs 31a to 31e are integrally formed on the outer edge of the shielding portion 32 by bending the legs 31a, 31b, 31c, 31d, and 31e, which extend radially outward from each of the five sides of the shielding portion 32, at approximately 90 degrees relative to the shielding portion 32. However, similar to the configuration in Figure 5(b), it is also possible to integrally form all of the legs 31a to 31e by forming only one of the multiple legs 31a to 31e provided in the circumferential direction of the shielding portion 32 integrally on the outer edge of the shielding portion 32, and then connecting the other legs along the circumferential direction of the shielding portion 32 starting from that leg. 【0047】 In this example of cover 3, the opening width of the groove 33 and the radial opening 34 is narrower than that of the cover 3 shown in Figures 1 to 8, making it possible to give more directionality to the exhaust gas ejection. Also, in this example, when the O-ring 4 is sandwiched between the valve body 2 and the cover 3, the width of the radial opening 34 becomes smaller than the outer diameter of the O-ring 4, so there is no need to separately provide members to form the restricting parts 35a and 35b as shown in Figures 6 and 7, and the legs 31a and 31e on both sides of the radial opening 34 can function as restricting parts 35c and 35d. 【0048】 In Figure 9, the cover 3 is shown as an example in which the shielding portion 32 is hexagonal to match the cross-sectional shape of the head 17 of the valve body 2. However, the sides of the shielding portion 32 do not need to be equal (it does not need to be a regular hexagon). The sides adjacent to the sides where no legs are formed may be made relatively longer, so that the parts where the grooves 33 and radial openings 34 open are relatively far from the center of the cover 3. In such a configuration, it is possible to further improve the directivity of the direction in which the exhaust gas is ejected. [Explanation of symbols] 【0049】 1. Safety valve 2 Valve body 3 Cover 4 O-rings 5 Internal passage 6 Inlet 7 First end 8 Outlet 9 Second end 10 Fitting part 19 Boss Section 31a,31b,31c,31d,31e Legs 32 Shielding part 33 Groove 34 Radial opening 35a,35b,35c,35d Regulation Department

Claims

[Claim 1] A safety valve (1) for a compressor that discharges exhaust gas to the outside when the internal pressure of the compressor (100) rises above a predetermined pressure, A columnar valve body (2) comprises an internal passage (5) through which exhaust gas flows, a first end (7) with an inlet (6) of the internal passage (5) open, a second end (9) with an outlet (8) of the internal passage (5) open, and a fitting portion (10) formed on its outer circumferential surface. A cover (3) having legs (31a, 31b, 31c, 31d) that fit into the fitting portion (10) of the valve body (2) and a shielding portion (32) that faces the second end portion (9), The valve comprises an annular elastic body sandwiched between the second end (9) of the valve body (2) and the shielding portion (32) of the cover (3) so as to surround the outlet (8), The shielding portion (32) has a groove (33) that bulges out from the portion facing the inside of the elastic body to the outer edge of the shielding portion (32) so as to move away from the second end. The groove (33) is configured to form a passage between it and the valve body (2) for guiding the exhaust gas to the outside. A safety valve for a compressor characterized by the following features. [Claim 2] The safety valve for a compressor according to claim 1, characterized in that the elastic body is in close contact with the contact surface (9a) of the second end (9) of the valve body (2) over its entire circumference, and is in close contact with the shielding portion (32) of the cover (3) except for the portion facing the groove portion (33). [Claim 3] The safety valve for a compressor according to claim 1 or 2, characterized in that the elastic body is an O-ring (4). [Claim 4] A boss portion (19) having an outer diameter smaller than the inner diameter of the elastic body is formed on the contact surface (9a) of the valve body (2) protruding from the second end portion (9). The safety valve for a compressor according to claim 1, characterized in that the elastic body is arranged around the boss portion (19) provided at the second end portion (9) of the valve body (2). [Claim 5] The safety valve for a compressor according to claim 1, characterized in that the cover (3) has a radial opening (34) formed on the outer edge of the shielding portion (32) adjacent to the groove portion (33), and is provided with restricting portions (35a, 35b, 35c, 35d) for restricting the radial movement of the elastic body. [Claim 6] The safety valve for a compressor according to claim 5, characterized in that the width of the radial opening (34) is formed to be narrower than the outer diameter of the elastic body by the regulating portions (35a, 35b, 35c, 35d). [Claim 7] The safety valve for a compressor according to claim 6, characterized in that the regulating portion (35a, 35b) is formed by a protruding piece that extends from the leg portion (31a, 31d) to the radial opening (34). [Claim 8] The safety valve for a compressor according to claim 6, characterized in that the regulating portion (35c, 35d) is formed by leg portions (31a, 31e) adjacent to the radial opening. [Claim 9] The safety valve for a compressor according to claim 1, characterized in that the legs (31a, 31b, 31c, 31d, 31e) are formed in a plurality in the circumferential direction of the shielding portion (32), and each of the legs (31a, 31b, 31c, 31d, 31e) is integrally formed with the outer edge of the shielding portion (32). [Claim 10] The safety valve for a compressor according to claim 1, characterized in that the legs (31a, 31b, 31c, 31d, 31e) are formed in a plurality in the circumferential direction of the shielding portion (32), one of which leg (31a) is integrally formed with the outer edge of the shielding portion (32), and the other legs (31b, 31c, 31d) are connected along the circumferential direction of the shielding portion (32) starting from this leg (31a), so that all of the legs (31a, 31b, 31c, 31d, 31e) are integrally formed.

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