Compressor

Abstract

A piston (18) in this compressor (1) partitions the interior space of a cylinder (17) into a compression chamber (21) and an inlet chamber (22). The piston (18) has formed therein a connection channel (19A) that connects between the compression chamber (21) and the inlet chamber (22). An inlet valve (23) opens and closes an opening (19A1) of the connection channel (19A). The inlet valve (23) is formed in a plate-like shape, and comprises: a fixation part (23A) which is fixed to the piston (18); a blocking part (23B) which covers the opening (19A1); and a spring part (23C) which connects between the fixation part (23A) and the blocking part (23B). Of the piston (18), a spring part-opposing portion (19B) that opposes the spring part (23C) of the inlet valve (23) is dented deeper than a blocking part-opposing portion (19C) that opposes the blocking part (23B) of the inlet valve (23).

Description

[Technical field]

[0001] The present disclosure relates, for example, to compressors for generating compressed air. [Background technology]

[0002] For example, Patent Documents 1 and 2 disclose a compressor that draws air from the crank chamber into a compression chamber through a communication passage formed in the piston. In this case, the piston is provided with a plate-shaped valve (suction valve) for opening and closing the opening of the communication passage. [Prior art documents] [Patent documents]

[0003] [Patent Document 1] Japanese Patent Application Publication No. 07-208368 [Patent Document 2] JP 2017-106397 A Summary of the Invention

[0004] For example, even if the piston diameter (cylinder diameter) of the compressor is reduced, in order to ensure the air volume and pressure, it is necessary to increase the opening (port diameter) of the communication passage and the lift amount of the plate-shaped valve (suction valve). On the other hand, if the opening of the communication passage is increased, the area of ​​the blocking part for blocking the opening increases in the entire valve. This makes it difficult to secure the spring part for increasing the lift amount, and there is a possibility that it becomes difficult to secure the lift amount.

[0005] An object of one embodiment of the present invention is to provide a compressor that can achieve both "increasing the opening of the piston communication passage" and "increasing the lift amount of the suction valve".

[0006] One embodiment of the present invention relates to a piston that divides a cylinder into a first chamber and a second chamber and that reciprocates, a communication passage formed in the piston that communicates between the first chamber and the second chamber, an opening at one end of the communication passage and provided on one side surface of the piston facing the first chamber, and a suction valve that opens and closes the opening, the suction valve being plate-shaped and having a fixed portion fixed to the center of the one side surface, a blocking portion on one radial side of the fixed portion, and a spring portion on the other radial side of the fixed portion, a spring portion facing portion on the one side surface that faces the spring portion being recessed more than a blocking portion facing portion that faces the blocking portion, and the spring portion has The bearing includes a straight portion extending radially outward from the fixed portion, a first bent portion formed in a U-shape from one end side of the straight portion toward the radially inward, and a second bent portion formed in a U-shape from the other end side of the first bent portion toward the radially outward. It is a compressor that uses

[0007] According to one embodiment of the present invention, it is possible to achieve both "increasing the opening of the piston communication passage" and "increasing the lift amount of the intake valve". [Brief description of the drawings]

[0008] [Figure 1] 1 is a vertical cross-sectional view showing a linear motor type compressor according to an embodiment. [Diagram 2] FIG. 2 is an exploded perspective view showing a piston, an intake valve, etc. [Diagram 3] FIG. [Figure 4] FIG. 2 is a perspective view showing a state in which the intake valve is attached to the piston. [Diagram 5] 1 is an explanatory diagram showing, in an exaggerated manner, a state in which a spring portion of the suction valve is elastically deformed (a state in which a closing portion is separated from an opening of a communication passage of the piston). FIG. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0009] Hereinafter, a compressor according to an embodiment will be described with reference to the accompanying drawings, taking as an example a case where the compressor is configured as a linear motor type compressor. In this embodiment, the linear motor type compressor is attached to a vehicle body as a part of an air suspension system of a four-wheeled automobile.

[0010] In Fig. 1, the linear motor type compressor 1 is configured as an air compressor. The compressor 1 can be used, for example, as a compressor (normal compressor) that draws in and compresses the atmosphere, and / or as a compressor (booster compressor) that draws in compressed air (compressed air) from a tank or the like and further compresses it. The compressor 1 includes a linear motor 2 that serves as a driving source, and a compression section 16 having a cylinder 17 and a piston 18. The linear motor 2 reciprocates the mover 5 in the length direction (left and right direction in Fig. 1) by passing a current through a coil (not shown) of the armature 4, thereby reciprocating the piston 18 of the compression section 16 in the same direction.

[0011] The linear motor 2 is attached to, for example, the body (not shown) of a vehicle (automobile) together with the compression unit 16. The linear motor 2 is configured to include a casing 3 forming an outer shell, and an armature 4, a mover 5, a support member 6, and a spring 7 arranged in the casing 3. The casing 3 of the linear motor 2 is formed as a hollow container. Specifically, the casing 3 is configured to include a cylindrical case main body 3A with both axial ends open, a cylinder side partition wall portion 3B closing the cylinder 17 side (for example, the left side in FIG. 1) which is one axial side, and an inverter side partition wall portion 3C closing the inverter 15 side (for example, the right side in FIG. 1) which is the other axial side. The casing 3 accommodates the armature 4, the mover 5, the support member 6, and the spring 7.

[0012] The armature 4 and the mover 5 generate magnetic attractive and repulsive forces between them when electricity is applied to the armature 4. This drives the flat-plate mover 5 to repeatedly reciprocate in the length direction (= the axial direction of the cylinder 17) within the casing 3 between the pair of armatures 4. The spring 7 is formed, for example, of a compression coil spring, and constantly biases the mover 5 toward one side (the cylinder 17 side) in the length direction of the casing 3. The spring 7 is elastically flexibly deformed to expand and contract as the mover 5 reciprocates.

[0013] A casing 3 of the linear motor 2 houses a motor including an armature 4 and a mover 5. Of these, the mover 5 protrudes from the casing 3 toward the inside of a cylinder 17 of a compression section 16. The mover 5 has an output shaft 8 that reciprocates when driven by the linear motor 2. A piston 18 is provided on the protruding end side of the output shaft 8. The output shaft 8 corresponds to a piston rod.

[0014] The piston 18 side of the output shaft 8 is a piston support portion 10 that supports the piston 18. That is, the piston 18 side of the output shaft 8 is composed of a rod portion 9 extending in the axial direction and a piston support portion 10 connected to the rod portion 9. The rod portion 9 of the output shaft 8 is supported by the cylinder side partition portion 3B via a sliding bearing 11 so as to be displaceable in the axial direction. The piston support portion 10 is attached to the tip of the rod portion 9. That is, the piston support portion 10 is provided on the tip side (piston 18 side) of the rod portion 9. In this case, the piston support portion 10 is formed in a disk shape having an outer diameter smaller than that of a lip ring 20 that constitutes the piston 18.

[0015] As shown in FIG. 2, the piston support part 10 includes a cylindrical central part 10A, a ring part 10B located on the outer diameter side of the central part 10A, and a plurality of (for example, three) connecting parts 10C located between the central part 10A and the ring part 10B and connecting them. The connecting parts 10C adjacent to each other in the circumferential direction form an air passage 12 connected to the communication passage 19A of the piston 18. As a result, the piston support part 10 includes the air passage 12 that communicates the communication passage 19A of the piston 18 with the suction chamber 22 of the compression part 16. The central part 10A of the piston support part 10 is provided with a female thread 10D into which the mounting screw 13 is screwed. The piston 18 (i.e., the piston body 19 and the lip ring 20) and the suction valve 23 are attached to the piston support part 10 by the mounting screw 13.

[0016] 1, a cylindrical inverter case 14 with a bottom is provided on the other side in the longitudinal direction of the casing 3, i.e., on the opposite side to the compression section 16. An inverter 15 that controls the driving of the linear motor 2 is provided inside the inverter case 14. The inverter 15 is configured to include, for example, a power transistor that generates a high voltage for energizing the armature 4, etc.

[0017] The compression section 16 of the linear motor type compressor 1 is provided, for example, sandwiched between the linear motor 2 and an air dryer 28. The compression section 16 includes a cylinder 17, a piston 18, a suction valve 23, a discharge valve 24, and a cylinder head 25. The compression section 16 compresses air (or already compressed air) in the cylinder 17 by the piston 18 reciprocating in the axial direction together with the mover 5 of the linear motor 2, thereby generating compressed air (or further compressed air).

[0018] The cylinder 17 is formed in a cylindrical shape with a bottom using a metal material such as aluminum. The cylinder 17 includes a cylindrical tube portion 17A and a bottom portion 17B that closes one end side (for example, the left side in FIG. 1) of the tube portion 17A. The bottom portion 17B is provided with a discharge hole 17C penetrating the bottom portion 17B. The cylinder 17 is attached to the cylinder side partition wall portion 3B of the casing 3. That is, the cylinder side partition wall portion 3B is provided with an attachment tube portion 3D that protrudes toward the cylinder 17 side and into which the tube portion 17A of the cylinder 17 is fitted. The cylinder 17 is attached to the casing 3 by being sandwiched between the cylinder side partition wall portion 3B and the cylinder head 25 in a state where the cylinder 17 is fitted into the attachment tube portion 3D of the cylinder side partition wall portion 3B.

[0019] A piston 18 is accommodated inside the cylinder 17 so as to be able to reciprocate (slide). The piston 18 is connected to the mover 5 of the linear motor 2. As a result, the piston 18 is provided inside the cylinder 17 so as to be able to slide in the length direction of the linear motor 2 (casing 3) (i.e., the axial direction of the cylinder 17, which is the left-right direction in FIG. 1). That is, the piston 18 reciprocates inside the cylinder 17 in conjunction with the reciprocating movement of the mover 5. In this way, the piston 18 is arranged on the same axis as the moving direction of the mover 5 of the linear motor 2.

[0020] The piston 18 is inserted into the cylinder 17 so as to be capable of reciprocating motion. The piston 18 divides the inside of the cylinder 17 into a compression chamber 21 and a suction chamber 22. The piston 18 is provided with a communication passage 19A that communicates the suction chamber 22 with the compression chamber 21, and a suction valve 23 that covers the communication passage 19A in an openable and closable manner. In this case, the piston 18 includes a piston body 19 in which the communication passage 19A is provided, and a lip ring 20 provided on the outer periphery of the piston body 19. An insertion hole 19E through which the mounting screw 13 is inserted is provided in the center of the piston body 19. The lip ring 20 seals between the piston 18 and the cylinder 17. The lip ring 20 is formed as a seal member having an L-shaped cross section and made of, for example, a resin material having wear resistance and self-lubricating properties.

[0021] The compression chamber 21 is formed as a cylindrical space surrounded by the tubular portion 17A, the bottom portion 17B, and the piston 18 of the cylinder 17. The suction chamber 22, also called an intake chamber, is formed as a cylindrical space surrounded by the tubular portion 17A of the cylinder 17, the cylinder side partition wall portion 3B of the casing 3, the piston 18, and the rod portion 9 of the output shaft 8. External air (or compressed air) flows into the suction chamber 22 via a suction port 3E provided in the cylinder side partition wall portion 3B of the casing 3.

[0022] Suction valve 23, also called an intake valve, is provided on the compression chamber 21 side of piston 18. That is, suction valve 23 is formed in a plate shape and attached to piston 18. Suction valve 23 includes fixed portion 23A fixed to piston 18, closing portion 23B that covers opening 19A1 of communication passage 19A of piston 18 in an openable and closable manner, and spring portion 23C that elastically deforms to tilt closing portion 23B in a direction away from opening 19A1 of communication passage 19A.

[0023] The suction valve 23 opens (opens) the communication passage 19A of the piston 18 during the suction stroke of the compression section 16 (piston 18), thereby communicating the suction chamber 22 in the cylinder 17 with the compression chamber 21. During the compression stroke of the compression section 16 (piston 18), the suction valve 23 closes (closes) the communication passage 19A of the piston 18, thereby isolating communication between the compression chamber 21 in the cylinder 17 and the suction chamber 22.

[0024] 1, the discharge valve 24 is provided between the bottom 17B of the cylinder 17 and the cylinder head 25. The discharge valve 24 covers one end of the cylinder 17 (more specifically, the discharge hole 17C of the bottom 17B of the cylinder 17) in an openable and closable manner. The discharge valve 24 is composed of, for example, a base 24A sandwiched between the bottom 17B of the cylinder 17 and the cylinder head 25, a notch 24B having a semicircular annular shape, and a closing portion 24C located inside the notch 24B and covering the discharge hole 17C in an openable and closable manner.

[0025] The discharge valve 24 (closing portion 24C) closes the discharge hole 17C during the suction stroke of the compression section 16 to block communication between the compression chamber 21 in the cylinder 17 and the discharge chamber 26 in the cylinder head 25. The discharge valve 24 (closing portion 24C) opens the discharge hole 17C during the compression stroke of the compression section 16 to communicate between the compression chamber 21 in the cylinder 17 and the discharge chamber 26 in the cylinder head 25.

[0026] The cylinder head 25 is attached to one end side of the cylinder 17 (for example, the left end side in FIG. 1) so as to cover the bottom part 17B of the cylinder 17. The cylinder head 25 is formed in a cylindrical shape with a bottom. A discharge chamber 26 is formed between the cylinder head 25 and the bottom part 17B of the cylinder 17. The cylinder head 25 is provided on the air dryer 28 side as a discharge part from which compressed air is discharged. In this case, a plurality of fasteners 27 are provided between the cylinder head 25 and the casing 3 (cylinder side partition part 3B) of the linear motor 2 to connect and fix the two together.

[0027] The fixing device 27 is disposed radially outside the cylinder 17 with a circumferential gap therebetween between the cylinder head 25 and the casing 3 (cylinder side partition wall portion 3B) of the linear motor 2. The fixing device 27 holds the cylinder 17 between the cylinder head 25 and the casing 3 (cylinder side partition wall portion 3B) of the linear motor 2. The cylinder head 25 is provided with a discharge port 25A that communicates with the air dryer 28. The discharge port 25A communicates between the discharge chamber 26 and the air dryer 28.

[0028] The air dryer 28 is attached to one end side of the cylinder head 25 (for example, the left end side in FIG. 1). That is, the air dryer 28 is provided on the opposite side of the linear motor 2 across the compression section 16. The inside of the air dryer 28 is filled with a desiccant. The air dryer 28 brings the desiccant into contact with the compressed air discharged from the compression section 16, so that the desiccant absorbs moisture in the compressed air and dries the air.

[0029] However, in order to ensure the air volume and pressure even if the piston diameter (cylinder diameter) of the compressor is reduced, it is necessary to increase the opening (port diameter) of the communication passage and the lift amount of the plate-shaped valve (suction valve, intake valve). On the other hand, for example, if the opening of the communication passage is increased, the area of ​​the blocking part for blocking the opening increases in the entire valve. This makes it difficult to secure the spring part for increasing the lift amount, and there is a possibility that it becomes difficult to secure the lift amount.

[0030] That is, when a suction valve (intake valve) is provided on a piston in a compressor, a plate-like suction valve constitutes the "portion that blocks the opening (blocking portion)" and the "portion that determines the stroke (spring portion)." In this case, if the piston diameter is reduced to reduce the load at high pressure, it may become difficult to simultaneously "secure the area of ​​the opening (port diameter)" and "secure the spring portion to increase the lift amount."

[0031] Therefore, in this embodiment, the center of the suction valve 23 is fixed to the piston 18 as the fixed portion 23A. At the same time, one radial side of the center (fixed portion 23A) is made into a blocking portion 23B that covers the opening 19A1 of the communication passage 19A in an openable and closable manner, and the area of ​​the opening 19A1 blocked by the blocking portion 23B is ensured. In addition, the other radial side of the center (fixed portion 23A) is made into a spring portion 23C. And, a relief step is provided on the seat surface of the spring portion 23C (the portion 19B facing the spring portion of the piston 18).

[0032] Furthermore, the spring portion 23C is provided with bent portions 23C1, 23C2, and 23C3 to reduce the spring constant. As a result, in this embodiment, the opening 19A1 of the communication passage 19A of the piston 18 can be enlarged, and the lift amount of the intake valve 23 (the amount that the closing portion 23B moves away from the opening 19A1) can be increased. These points will be described below.

[0033] As shown in FIG. 1 to FIG. 5, the compressor 1 of this embodiment has a piston 18, a communication passage 19A, an opening 19A1, and a suction valve 23. The piston 18 divides the inside of the cylinder 17 into a compression chamber 21 serving as a first chamber and a suction chamber 22 serving as a second chamber. The piston 18 reciprocates inside the cylinder 17. The communication passage 19A is formed in the piston 18. More specifically, the communication passage 19A is provided in a piston body 19 constituting the piston 18 as a through hole penetrating the piston body 19 in the axial direction. The communication passage 19A communicates with the suction chamber 22 via the ventilation passage 12 of the piston support portion 10. As a result, the communication passage 19A communicates between the compression chamber 21 and the suction chamber 22.

[0034] The opening 19A1 is one end of the communication passage 19A, and is provided on one side surface of the piston 18 on the compression chamber 21 side (for example, the left side surface in FIG. 1, the upper side surface in FIG. 2). As shown in FIG. 2, the opening 19A1 is formed in an arc shape extending from the first end E1 to the second end E2 along the outer diameter (outer peripheral edge) of one side surface of the piston 18. The angle of the opening 19A1 formed by the first end E1, the second end E2, and the center O of the one side surface is greater than 180 degrees. That is, the opening 19A1 is located on the outer diameter side of the circular piston 18 (piston main body 19) and is formed in an arc shape extending circumferentially by more than 180 degrees.

[0035] Suction valve 23 opens and closes opening 19A1 of communication passage 19A of piston 18 (piston body 19). As shown in FIG. 2, suction valve 23 is plate-shaped. More specifically, suction valve 23 is substantially disk-shaped. Suction valve 23 has fixed portion 23A, closing portion 23B, and spring portion 23C. Fixed portion 23A is fixed to the center of one side surface (surface on the compression chamber 21 side) of piston 18. For this purpose, fixed portion 23A is provided with mounting hole 23A1 through which mounting screw 13 is inserted.

[0036] The blocking portion 23B is disposed on one radial side of the fixed portion 23A (for example, the right side in the left-right direction in Figs. 2 and 4, and the upper side in the up-down direction in Fig. 3). In this case, the blocking portion 23B is disposed at a position corresponding to the opening 19A1 of the communication passage 19A of the piston 18 (piston body 19). The blocking portion 23B is a portion that covers the opening 19A1 of the piston 18 in an openable and closable manner, and extends in the circumferential direction by more than 180 degrees like the opening 19A1 of the piston 18. The spring portion 23C is disposed on the other radial side of the fixed portion 23A (for example, the left side in the left-right direction in Figs. 2 and 4, and the lower side in the up-down direction in Fig. 3). The spring portion 23C is provided on the radial opposite side of the blocking portion 23B across the fixed portion 23A. The spring portion 23C has at least two bent portions, more specifically, three bent portions 23C1, 23C2, and 23C3.

[0037] That is, the spring portion 23C includes a straight portion 23C4 extending radially outward from the fixed portion 23A, a first bent portion 23C1, 23C1 that is bent back approximately 180° in a U-shape from one end side (the outer diameter side of the suction valve 23) of the straight portion 23C4 radially inward, a second bent portion 23C2, 23C2 that is bent back approximately 180° in a U-shape from the other end side (the inner diameter side of the suction valve 23) of the first bent portion 23C1, 23C1 radially outward, and a third bent portion 23C3, 23C3 that is bent approximately 90° in the circumferential direction from one end side (the outer diameter side of the suction valve 23) of the second bent portion 23C2, 23C2 and connected to the blocking portion 23B.

[0038] Such spring portion 23C elastically deforms as shown in Fig. 5, thereby tilting closing portion 23B in a direction away from opening 19A1 of piston 18. Note that Fig. 5 shows an exaggerated view of the state in which spring portion 23C of suction valve 23 is elastically deformed (i.e., the state in which closing portion 23B is away from opening 19A1 of piston 18 (piston main body 19)).

[0039] Furthermore, a positioning recess 23C5 is provided on the outer circumferential edge of suction valve 23 at a position corresponding to spring portion 23C (more specifically, at a position corresponding to one end side of straight portion 23C4). Positioning recess 23C5 is formed as a notch recessed radially inward from the outer circumferential edge of suction valve 23. Positioning recess 23C5 engages with rotation restriction portion 19D provided on piston 18 (piston body 19).

[0040] On the other hand, one side surface of the piston 18 (piston body 19), i.e., the surface on the compression chamber 21 side (the surface on the suction valve 23 side), serves as a seat surface for the suction valve 23. This seat surface has a spring portion facing portion 19B facing the spring portion 23C of the suction valve 23, and a closing portion facing portion 19C facing the closing portion 23B of the suction valve 23. The communication passage 19A of the piston 18 (piston body 19) opens to the closing portion facing portion 19C. And, the spring portion facing portion 19B of one side surface of the piston 18 (piston body 19) is recessed from the closing portion facing portion 19C. In other words, the spring portion facing portion 19B serves as a step surface (relief surface) recessed with respect to the closing portion facing portion 19C. Therefore, as shown in Figure 5, when the spring portion 23C elastically deforms, the suction valve 23 enters into the spring portion opposing portion 19B, which is located lower than the occlusion portion opposing portion 19C, thereby allowing the occlusion portion 23B to be tilted in a direction significantly away from the opening 19A1 of the piston 18.

[0041] 2 and 4, the spring portion facing portion 19B is formed with a rotation restricting portion 19D that restricts the rotation of the suction valve 23. The rotation restricting portion 19D is provided on the outer diameter side of the spring portion facing portion 19B at a position corresponding to the positioning recess 23C5 of the suction valve 23. The rotation restricting portion 19D restricts the rotation of the suction valve 23 by engaging with the positioning recess 23C5 of the suction valve 23. That is, the suction valve 23 can be positioned in the rotational direction relative to the piston 18 (piston main body 19) by the engagement between the positioning recess 23C5 of the suction valve 23 and the rotation restricting portion 19D of the piston 18 (piston main body 19).

[0042] Thus, according to this embodiment, the cylinder 17 is provided with a piston 18 that divides the cylinder 17 into a compression chamber 21 serving as a first chamber and a suction chamber 22 serving as a second chamber and that reciprocates within the cylinder 17. The piston 18 is provided with a communication passage 19A that communicates the compression chamber 21 with the suction chamber 22. The piston 18 is also provided with a suction valve 23 that opens and closes the communication passage 19A. As shown in FIG. 1, the compression chamber 21 is provided with a discharge valve 24, and the compression chamber 21 is connected to a discharge port 25A via the discharge valve 24. The suction chamber 22 is connected to a suction port 3E, also called an intake port.

[0043] 2, suction valve 23 has fixed portion 23A, which is the center portion, fixed to one side surface (seat surface) of piston 18 (piston body 19) by mounting screw 13. A communication passage 19A leading to suction chamber 22 below piston 18 is opened on one radial side of one side surface of piston 18 (piston body 19). In addition, a spring portion facing portion 19B, which serves as a relief step so as not to interfere with the operation (elastic deformation) of spring portion 23C when suction valve 23 is opened, is provided on the other radial side of one side surface of piston 18 (piston body 19), i.e., on the radial opposite side to opening 19A1 of communication passage 19A.

[0044] The spring portion facing portion 19B is recessed in a direction away from the suction valve 23 more than the blocking portion facing portion 19C. In addition, the spring portion facing portion 19B is provided with a rotation restricting portion 19D that restricts the rotation of the suction valve 23 and protrudes from the spring portion facing portion 19B. As shown in FIG. 3, the suction valve 23 has a fixed portion 23A in the center, a blocking portion 23B that is provided on one radial side of the fixed portion 23A and closes the opening 19A1 of the communication passage 19A, and a spring portion 23C that is provided on the other radial side of the fixed portion 23A and connects the fixed portion 23A and the blocking portion 23B. The spring portion 23C is provided with bent portions 23C1, 23C2, and 23C3.

[0045] The linear motor type compressor 1 according to this embodiment has the above-mentioned configuration, and its operation will now be described.

[0046] First, when a current is supplied (energized) to the coils (not shown) of the armature 4 of the linear motor 2, the mover 5 receives a thrust in the axial direction. At this time, magnetic attractive and repulsive forces are generated between the armature 4 and the mover 5 due to the current passing through each coil (not shown) of the armature 4, and as a result, the flat mover 5 repeats reciprocating motion in the length direction (axial direction) within the casing 3 between the pair of armatures 4.

[0047] The thrust caused by the reciprocating motion of the mover 5 is transmitted to the piston 18 in the cylinder 17 constituting the compression section 16. The piston 18 repeatedly reciprocates in the axial direction in the cylinder 17 to perform compression operation. That is, during the suction stroke in which the piston 18 moves toward the suction chamber 22, the pressure in the compression chamber 21 decreases and the suction valve 23 opens. As a result, air (or compressed air) is sucked in from the suction port 3E, and the air (or compressed air) on the suction chamber 22 side flows to the compression chamber 21 side through the air passage 12 of the piston support section 10 and the communication passage 19A of the piston 18.

[0048] Next, during the compression stroke in which piston 18 moves toward compression chamber 21, suction valve 23 closes. This causes the pressure in compression chamber 21 to rise, discharge valve 24 opens, and compressed air is discharged to discharge port 25A via discharge chamber 26. The compressed air discharged from discharge port 25A is dried, for example, by air dryer 28, and then supplied into the air chamber of the vehicle's air suspension.

[0049] When the suction valve 23 opens, the bent portion 23C3 of the spring portion 23C elastically deforms toward the seat surface as shown in Fig. 5. On the seat surface side of the piston 18 (piston body 19), the spring portion facing portion 19B, which serves as a relief step, is provided recessed from the blocking portion facing portion 19C. Therefore, the operation (elastic deformation) of the spring portion 23C is not hindered, and the lift amount of the suction valve 23 can be increased.

[0050] In addition, since the spring portion 23C is provided with the bent portions 23C1, 23C2, and 23C3, even if the spring portion 23C is less than half the seat surface, the length of the spring portion 23C (i.e., the connection length from the fixed portion 23A to the blocking portion 23B) can be increased and the spring constant can be reduced. As a result, the passage area of ​​the communication passage 19A can be secured and the suction resistance can be reduced.

[0051] As described above, according to the present embodiment, the piston 18 includes the spring portion facing portion 19B facing the spring portion 23C of the suction valve 23, and the blocking portion facing portion 19C facing the blocking portion 23B of the suction valve 23. In addition, the spring portion facing portion 19B is recessed from the blocking portion facing portion 19C. Therefore, when the spring portion 23C of the suction valve 23 elastically deforms and the blocking portion 23B moves away from the opening 19A1 of the communication passage 19A, the spring portion 23C enters (depresses) into the spring portion facing portion 19B, which is recessed from the blocking portion facing portion 19C. This makes it easier for the blocking portion 23B to tilt in a direction away from the opening 19A1.

[0052] Therefore, even if the opening 19A1 of the communication passage 19A of the piston 18 is enlarged, the amount by which the blocking portion 23B of the suction valve 23 moves away from the opening 19A1 (the lift amount) can be increased. As a result, it is possible to both "enlarge the opening 19A1 of the communication passage 19A of the piston 18" and "increase the lift amount of the suction valve 23." Therefore, even if the diameter of the piston 18 of the compressor 1 is reduced, the opening 19A1 of the communication passage 19A of the piston 18 can be enlarged and the lift amount of the suction valve 23 can be increased, so that in addition to reducing the load at high pressure, the air volume and pressure can be secured.

[0053] According to this embodiment, the opening 19A1 of the communication passage 19A of the piston 18 extends more than 180 degrees along the outer diameter (outer peripheral edge) of the piston 18. This allows the opening 19A1 of the communication passage 19A to be large, thereby improving the efficiency of the compressor 1.

[0054] According to this embodiment, the spring portion 23C of the suction valve 23 has at least two bent portions, more specifically, three bent portions 23C1, 23C2, and 23C3. Therefore, the length of the spring portion 23C (the connection length from the fixed portion 23A to the closing portion 23B) can be secured, and the spring constant can be reduced. This allows the lift amount to be increased, and the amount of discharged air to be secured.

[0055] According to this embodiment, a rotation restricting portion 19D that restricts the rotation of the suction valve 23 is formed on the spring portion opposing portion 19B of the piston 18. Therefore, when the suction valve 23 is attached to the piston 18, the suction valve 23 can be positioned by the rotation restricting portion 19D. This makes it possible to easily attach the suction valve 23 to the piston 18.

[0056] In the embodiment, the spring portion 23C of the suction valve 23 is configured to have three bent portions 23C1, 23C2, and 23C3. However, the present invention is not limited to this, and the number of bent portions of the spring portion may be one or two, or four or more.

[0057] In the embodiment, the opening 19A1 of the communication passage 19A is an arc-shaped opening that extends more than 180 degrees in the circumferential direction. However, the present invention is not limited to this, and the opening of the communication passage may be an arc-shaped opening of 180 degrees or less. Furthermore, the opening is not limited to an arc-shaped opening, and may have a shape other than an arc-shaped opening, such as a fan-shaped, polygonal, or linear shape. Furthermore, the configuration may include multiple communication passages or multiple openings.

[0058] In the embodiment, the piston 18 of the compression section 16 is an oscillating piston that is directly connected to the output shaft 8 (rod section 9) that serves as a piston rod. However, the present invention is not limited to this, and the piston may be a normal piston that is connected to a piston rod via a piston pin.

[0059] In the embodiment, a linear motor type compressor 1 in which the compression section 16 is driven by a linear motor 2 has been described as an example. However, the present invention is not limited to this, and for example, a configuration in which the compression section (piston) is driven (reciprocated) using a driving source other than a linear motor may be used. That is, the compressor may be a compressor in which a piston reciprocates. In addition, the compressor may be used as a compressor (normal compressor) that draws in and compresses the atmosphere, or as a compressor (booster compressor) that draws in compressed air (compressed air) from a tank or the like and further compresses it. Furthermore, the compressor may compress gas other than air.

[0060] In the embodiment, the compressor 1 is mounted on a vehicle. In this case, the compressor 1 may be applied to a closed-type air suspension system that can store compressed air in a tank. Also, the compressor 1 may be applied to an open-type air suspension system that does not use a tank for storing compressed air (i.e., a system that exhausts compressed air to the outside), for example.

[0061] In the embodiment, the compressor 1 is described as being mounted on a vehicle. However, the present invention is not limited to this, and may be mounted on various machines that require a compressor. That is, the compressor may be mounted on various machines other than a vehicle. The compressor may also be used alone.

[0062] In the embodiment, an example has been described in which the central axis of the linear motor 2, the central axis of the compression unit 16, and the central axis of the air dryer 28 are arranged so as to coincide with each other. However, this is not limiting, and for example, the central axis of the compression unit and the central axis of the air dryer are not excluded from being arranged at positions offset from the central axis of the linear motor. In addition, the central axis of the linear motor and the central axis of the air dryer may be offset from the central axis of the compression unit, or the central axis of the linear motor and the central axis of the compression unit may be offset from the central axis of the air dryer.

[0063] According to the embodiment described above, the piston includes a spring portion facing portion that faces the spring portion of the suction valve, and a blocking portion facing portion that faces the blocking portion of the suction valve. In addition, the spring portion facing portion is recessed more than the blocking portion facing portion. Therefore, when the spring portion of the suction valve elastically deforms and the blocking portion moves away from the opening of the communication passage, the spring portion enters (lowers) into the spring portion facing portion that is recessed more than the blocking portion facing portion, so that the blocking portion can be easily tilted in the direction away from the opening. This allows the amount by which the blocking portion of the suction valve moves away from the opening (lift amount) to be increased even if the opening of the communication passage of the piston is increased. As a result, it is possible to achieve both "increasing the opening of the communication passage of the piston" and "increasing the lift amount of the suction valve". Therefore, even if the piston diameter of the compressor is reduced, the opening of the communication passage of the piston can be increased and the lift amount of the suction valve can be increased, so that the load at high pressure can be reduced and the air volume and pressure can be secured.

[0064] According to the embodiment, the opening of the communication passage of the piston extends more than 180 degrees along the outer diameter (outer peripheral edge) of the piston, which allows the opening of the communication passage to be made larger, thereby improving the efficiency of the compressor.

[0065] According to the embodiment, the spring portion of the suction valve has at least two bent portions. This allows the length of the spring portion to be secured and the spring constant to be reduced. This allows the lift amount to be increased and the amount of discharged air to be secured.

[0066] According to the embodiment, the rotation restricting portion that restricts the rotation of the suction valve is formed on the portion of the piston facing the spring portion. Therefore, when the suction valve is attached to the piston, the rotation restricting portion can position the suction valve. This makes it possible to facilitate the work of attaching the suction valve to the piston. [Explanation of symbols]

[0067] 1: compressor, 2: linear motor, 17: cylinder, 18: piston, 19A: communication passage, 19B: spring portion facing portion, 19C: blocking portion facing portion, 19D: rotation restriction portion, 19A1: opening, 21: compression chamber (first chamber), 22: suction chamber (second chamber), 23: suction valve, 23A: fixed portion, 23B: blocking portion, 23C: spring portion, 23C1, 23C2, 23C3: bent portion, E1: first end, E2: second end, O: center

Claims

1. a piston that divides the inside of a cylinder into a first chamber and a second chamber and reciprocates; a communication passage formed in the piston, the communication passage connecting the first chamber and the second chamber; an opening at one end of the communication passage, the opening being provided on one side surface of the piston on the first chamber side; a suction valve for opening and closing the opening, The suction valve is plate-shaped, A fixing portion fixed to the center of the one side surface; A blocking portion on one radial side of the fixing portion; a spring portion on the other radial side of the fixed portion, a spring portion facing portion of the one side surface facing the spring portion is recessed more than a blocking portion facing portion facing the blocking portion, The spring portion includes a straight portion extending radially outward from the fixed portion, a first bent portion formed in a U-shape from one end side of the straight portion extending radially inward, and a second bent portion formed in a U-shape from the other end side of the first bent portion extending radially outward.

2. The opening is formed in an arc shape extending from a first end to a second end along an outer diameter of the one side surface, The compressor according to claim 1 , wherein an angle formed between the first end, the second end and a center of the one side surface is greater than 180 degrees.

3. The compressor according to claim 1 , wherein the spring portion facing portion of the one side surface is formed with a rotation restricting portion that restricts rotation of the suction valve.

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