JP4232705B2 - Swing compressor - Google Patents

Description

  The present invention relates to a swing compressor used in a refrigeration apparatus or the like, and particularly relates to a structure of a portion corresponding to a discharge port at a discharge end position of a piston.

Conventionally, as a swing compressor, for example, as disclosed in Patent Document 1, a cylinder having a cylinder chamber in which a suction port and a discharge port are opened, and a cylinder chamber are disposed on both sides in the axial direction of the cylinder. A side housing, an annular piston disposed in the cylinder chamber and having an inner peripheral portion rotatably fitted to an eccentric shaft portion of the drive shaft, and a projectingly coupled outer peripheral portion of the piston, A blade that divides the cylinder chamber into a low-pressure chamber that communicates with the suction port and a high-pressure chamber that communicates with the discharge port; and a swingable opening provided in a hole formed in the cylinder facing the cylinder chamber. And a swinging bush that supports the swinging and reciprocating movement of the side, and as the drive shaft rotates, the piston is revolved in the cylinder chamber with the swinging bush as a fulcrum through the blade. The per revolution of the piston to compress the fluid, such as refrigerant gas sucked from the suction port those to be discharged from the discharge outlet are known. The suction port and the discharge port are both formed in the cylinder and open to the cylinder chamber in a direction perpendicular to the axial direction. The hole of the swing bush is provided so as to face the cylinder chamber at the compression end position for each revolution of the piston when the cylinder chamber is divided into a low pressure chamber and a high pressure chamber by a blade.
JP-A-6-147164

  However, in the above-described conventional one, the hole of the swing bush is provided in the cylinder at the compression end position for each revolution of the piston. Therefore, in order to prevent the strength of the cylinder from being lowered, discharge is performed at a position away from the hole. It is necessary to open the outlet to the cylinder. However, if the discharge port is away from the compression end position (near the hole) for each revolution of the piston, the discharge start angle of the discharge valve becomes faster, and after the discharge valve is closed, the piston revolves to the compression end position. There is a risk that the invalid power of the swing compressor will be greatly increased, and there is a concern that the efficiency of the swing compressor will deteriorate.

  The present invention has been made in view of such a point, and an object of the present invention is to make the discharge port as close as possible to the compression end position of the piston so that it can be opened so that the discharge start angle of the discharge valve can be achieved. Is to reduce the reactive power of the piston to increase the efficiency of the swing compressor.

In order to achieve the above object, the solution provided by the invention of claim 1 includes a cylinder (6) having a cylinder chamber (6a) in which a suction port (21) and a discharge port (22) are opened, 6) side housings (7), (8) arranged so as to close the cylinder chamber (6a) on both sides in the axial direction and having the discharge port (22) formed on at least one of the axial sides. An annular piston (9) disposed in the cylinder chamber (6a) and having an inner peripheral portion rotatably fitted to an eccentric shaft portion (5a) of the drive shaft (5), and the piston (9 ) And a blade (31) dividing the cylinder chamber (6a) into a low pressure chamber (34) leading to the suction port (21) and a high pressure chamber (35) leading to the discharge port (22). And a bush hole (24) having a circular cross section and penetrating the cylinder (6) in the axial direction and a part thereof facing the cylinder chamber (6a) and opening to form an opening (24a), Cylinder (6) The drive shaft (5) is provided with a swing bush (32) provided swingably in the bush hole (24) and supporting the projecting tip side of the blade (31) so as to be swingable and reciprocating. With the rotation of the piston (9), the piston (9) revolves in the cylinder chamber (6a) with the swing bush (32) as a fulcrum through the blade (31), and each time the piston (9) revolves, the suction port (21 ) Is assumed to be a swing compressor (1) configured to compress the fluid sucked from) and discharge it from the discharge port (22). The discharge port (22) has a portion of the cylinder (6) that protrudes toward the opening (24a) and a swing bush (32) that slides against the portion of the cylinder (6). 6) is provided so as to overlap when viewed from the axial direction, and the portion overlapping the cylinder (6) occupies a larger area ratio than the portion overlapping the swing bush (32), Further, the discharge port (22) is provided at a position that does not overlap the blade (31) when viewed from the axial direction of the cylinder (6), and the cylinder (6) that overlaps the discharge port (22). ) And the swing bush (32), only the cylinder (6) is provided with a notch (51), and the notch (51) is located at the compression end position of the piston (9) and the high pressure chamber (35). Is formed by cutting out the cylinder surface on the discharge port (22) side so that it communicates with the discharge port (22). That.

  Thus, according to the first aspect of the present invention, the discharge port (22) has the piston (9) formed by a notch formed by cutting the surface of the cylinder (6) in the overlap portion with the discharge port (22) of the cylinder (6). Open as close to the compression end position as possible. Therefore, the fluid in the high pressure chamber (35) is smoothly discharged from the discharge port (22) along the notch even when the piston (9) approaches the compression end position, and the discharge port is opened in the cylinder. There is no need to separate the discharge port from the swing bushing hole that opens to the piston compression end position as in the case of the pump, and the discharge port (22) is as close as possible to the compression end position of the piston (9). It becomes possible to delay the discharge start angle of (23), and the reactive power of the piston (9) that revolves the piston (9) to the compression end position after the discharge valve (23) is closed is reduced. Moreover, since the notch is provided in the overlap portion with the discharge port (22) of the cylinder (6), the outer peripheral portion of the swing bush (32) on the low pressure chamber (34) side of the blade (31) and its The load acting on the swinging bush (32) from the high pressure chamber (35) side is received without trouble by the part of the cylinder (6) facing the outer periphery, and the swinging bush (32) Swing can be performed smoothly.

  The solution provided by the invention according to claim 3 is the invention according to claim 1, wherein the notch is formed so as to expand toward the discharge port (22).

  According to a fourth aspect of the present invention, there is provided a solution provided in the first or second aspect of the present invention, wherein the discharge port (22) has an area of a portion overlapping the cylinder (6) as the swing bush (32 ) And an area that overlaps the area of 4 to 9 times.

  As described above, according to the swing compressor of the present invention, the cutout portion is provided in the overlap portion of the cylinder surface on the discharge port side that overlaps the discharge port (22) at a large ratio in terms of area. As close as possible to the piston compression end position, the discharge start angle of the discharge valve is delayed, the reactive power of the piston after the discharge valve is closed is reduced, and the efficiency of the swing compressor can be improved. . In addition, the load from the high-pressure chamber side is received without trouble by the outer peripheral part of the low-pressure chamber side and the opposed part of the cylinder from the blade of the swinging bush, and the swinging of the swinging bush is smoothly performed without adversely affecting the notch. It can be carried out.

  Embodiments and reference techniques of the present invention will be described below with reference to the drawings.

  FIG. 4 shows the overall configuration of the swing compressor according to Reference Technology 1. The swing compressor (1) has a motor (3) disposed on the inner upper portion of a hermetic casing (2) and the motor. A compression element (4) is disposed on the lower side of (3), and the compression element (4) is rotationally driven by a drive shaft (5) extending from the motor (3). The compression element (4) is disposed in contact with the cylinder (6) having a cylinder chamber (6a) therein and the upper and lower open portions of the cylinder (6), and closes the upper and lower open portions. A head (7), a rear head (8), and a piston (9) rotatably disposed in the cylinder chamber (6a) are provided on bearings provided in the heads (7), (8). The lower side of the drive shaft (5) is supported by a bearing.

  Further, as shown in FIG. 3, the inner peripheral wall of the cylinder chamber (6a) is formed in a substantially circular cross section, and the piston (9) is formed in an annular shape. The shaft portion (5a) is rotatably fitted. The shaft center of the eccentric shaft portion (5a) is offset by a predetermined amount from the center point of the drive shaft (5), and the piston (9) does not rotate when the drive shaft (5) rotates. It revolves along the outer peripheral wall while being in contact with or close to the outer peripheral wall of the cylinder chamber (6a). An oil supply passage (10) that opens to the bottom oil sump (2a) in the casing (2) is provided on the center side of the drive shaft (5). The oil supply passage (10) is provided with a pump element (11) on the inlet side, and in the sliding contact surface between the eccentric shaft portion (5a) and the piston (9), that is, in the cylinder chamber (6a). The outlet is opened, and the lubricating oil pumped up from the bottom oil sump (2a) by the pump element (11) is supplied from the intermediate outlet into the cylinder chamber (6a) through the oil supply passage (10). Yes.

  Further, the cylinder (6) is provided with a suction port (21) that opens to the outer peripheral wall of the cylinder chamber (6a), and the suction port (21) is connected to the suction pipe (2b) from the outside of the sealed casing (2). ) Is connected. Further, as shown in FIG. 2, the front head (7) and the rear head (8) are provided with circular discharge ports (22), (22) respectively opened on the upper and lower walls of the cylinder chamber (6a). Each discharge port (22) is provided with a discharge valve (23) that opens when the pressure in the cylinder chamber (6a) (more specifically, a high pressure chamber (35) to be described later in detail) exceeds a predetermined value. . Each discharge valve (23) includes a valve body (23a) for opening and closing the discharge port (22), and a valve presser (23b) for restricting opening of the valve body (23a) by a predetermined amount or more by contact. It becomes. Further, a cylindrical bush hole (24) penetrating in the axial direction is formed in the cylinder (6) at a position between the suction port (21) and each discharge port (22), and the bush hole (24) And an opening (24a) that opens to face the cylinder chamber (6a) at a part of the circumference. In FIG. 4, (2c) is an external discharge pipe connected to the upper part of the hermetic casing (2).

  The piston (9) is integrally provided with a blade (31) extending in a radial direction from the outer peripheral surface thereof. The blade (31) is formed integrally with the piston (9), or is formed of separate members and is configured by connecting the two with a concave-convex fitting structure or an adhesive. The protruding tip side of the blade (31) is inserted into the bush hole (24), while the bush hole (24) has a pair of swing bushes (32), (32 ) Are slidably disposed, and both the oscillating bushes (32), (32) are disposed in the bush hole (24) while the blade (31) is sandwiched between the projecting tips. The blade is allowed to move forward and backward and swings in the bush hole (24) integrally with the blade (31). The blade (31) is connected to the low pressure chamber (34) leading to the suction port (21) through the cylinder chamber (6a) between the inner peripheral surface of the cylinder (6) and the outer peripheral surface of the piston (9). It is divided into a high-pressure chamber (35) that leads to the outlet (22), and in this state the cylinder chamber (so that the piston (9) swings with the swing bush (32) as a fulcrum via the blade (31). It is configured to revolve along the outer peripheral wall of 6a) and to compress the fluid such as the refrigerant gas sucked from the suction port (21) and discharge from each discharge port (22) at each revolution. In addition, a through hole (36) that penetrates both heads (7), (8) and the cylinder (6) is formed in the vicinity of each discharge port (22), and the lower side is formed through this through hole (36). The fluid discharged from the discharge port (22) is guided upward, that is, above the compression element (4). In this case, the bush hole (24) defines the cylinder chamber (6a) by dividing the cylinder chamber (6a) into the low pressure chamber (34) and the high pressure chamber (35) by the blade (31), and the compression end position for each revolution of the piston (9). And is provided so as to face the cylinder chamber (6a).

  As shown in FIG. 1, each of the discharge ports (22) has a semicircular portion of which the outer peripheral portion of the swing bush (32) on the high pressure chamber (35) side than the blade (31) and the upper and lower portions of the outer peripheral portion. It is provided so that it may overlap with the peripheral part (part) of the cylinder (6) facing the position when viewed from the axial direction of the cylinder (6). The swing bush (32) overlaps with each discharge port (22) at both the upper and lower positions of the outer periphery and the overlap portion with each discharge port (22) at both the upper and lower positions of the cylinder (6) And the upper and lower positions of the swinging bush (32) on the outer periphery of the swinging bush (32) so that the high pressure chamber (35) communicates with each discharge port (22) at the compression end position of the piston (9). The cylinder (6) is provided with a pair of upper and lower cutouts (41) and (41) each cut out from the vertical position of the peripheral edge (the cylinder (6) surface). Each notch (41) has a semi-conical shape in which the circumferential surface straddling between the two overlapping portions becomes wider toward the discharge port (22).

  Further, in this reference technique 1, an overlap portion with the discharge port (22) at both the upper and lower positions of the swing bush (32) on the high pressure chamber (35) side of the blade (31) and the cylinder (6) Among the overlapping portions with the discharge port (22) at both the upper and lower positions of the peripheral portion of the cylinder, the overlapping portion of the cylinder (6) occupies a larger area ratio (for example, a ratio of 80 to 90%). That is, the area of the overlap portion between the cylinder (6) and the discharge port (22) is, for example, 4 to 9 times the area of the overlap portion between the swing bush (32) and the discharge port (22).

  Therefore, in the above reference technique 1, the discharge port (22) is overlapped with the discharge port (22) at both the upper and lower positions of the swing bush (32) and at both the upper and lower positions of the cylinder (6). An opening is made as close as possible to the compression end position of the piston (9) by notches (41), (41) provided across the overlap portion with the discharge port (22). Therefore, the fluid in the high pressure chamber (35) is smoothly discharged from the discharge port (22) along the notch (41) even when the piston (9) approaches the compression end position, and is discharged to the cylinder. There is no need to separate the discharge port from the hole of the swinging bush that opens to the compression end position of the piston unlike the one that opens the outlet, and the discharge port (22) that is as close as possible to the compression end position of the piston (9) The discharge start angle of the discharge valve (23) can be delayed, and the reactive power of the piston (9) that revolves the piston (9) to the compression end position after the discharge valve (23) is closed is reduced. Therefore, the efficiency of the swing compressor (1) can be increased.

  Moreover, the notch (41) has an overlapping portion with the discharge port (22) at both the upper and lower positions of the swing bush (32) on the high pressure chamber (35) side of the blade (31) and the cylinder (6). Since it is provided in the overlapping part with the discharge port (22) at both the upper and lower positions of the peripheral part, the outer peripheral part of the swing bush (32) on the low pressure chamber (34) side than the blade (31) and the outer peripheral part thereof The load acting on the oscillating bushes (32), (32) from the high pressure chamber (35) side is received without any trouble by the peripheral edge of the opposing cylinder (6), and adverse effects are caused by the notches (41), (41). The swinging bush (32) can be smoothly swung without any trouble.

  Embodiments of the present invention will be described. In the above reference technique 1, the notches (41) and (41) are over-exposed with the discharge port (22) at both the upper and lower positions of the swinging bush (32) on the high pressure chamber (35) side of the blade (31). The wrap portion and the cylinder (6) were provided across the overlap portion with the discharge port (22) at both the upper and lower positions of the peripheral portion. On the other hand, in this embodiment, as shown in FIG. 5, the high pressure chamber (35) is discharged at the compression end position of the piston (9) only on the overlapping portion at both the upper and lower positions of the periphery of the cylinder (6). A pair of upper and lower notches (51) (only one is shown in the figure) is provided so that the upper and lower positions of the peripheral edge of the cylinder (6) are cut into a substantially semiconical shape so as to communicate with the outlet (22). Thus, the fluid in the high pressure chamber (35) can be smoothly discharged from the discharge port (22) along the cutout portion (51) of the overlap portion with the discharge port (22) of the cylinder (6). In addition, it is possible to simplify the manufacturing operation of the cutout portion (51) without making the cutout portion for the overlap portion of the swing bush (32), and to reduce the manufacturing cost.

  Next, the reference technique 2 will be described with reference to FIGS. In this reference technique 2, the position where the notch is provided is changed.

  That is, in the present reference technique, as shown in FIGS. 6 and 7, each of the discharge ports (22) has a semicircular portion thereof at the compression end position of the piston (9) with respect to the outer peripheral portion of the piston (9). The cylinder (6) is provided so as to overlap when viewed from the axial direction. The high pressure chamber (35) is connected to each discharge port (22) at the compression end position of the piston (9) at the overlap portion with each discharge port (22) at both the upper and lower positions of the piston (9). A pair of upper and lower notches (61) and (61) are provided so that both the upper and lower positions of the outer periphery of the piston (9) are cut into a semiconical shape so as to communicate with each other. The rest of the configuration excluding the notch (61) is the same as in the case of the reference technique 1, and the same parts are denoted by the same reference numerals and detailed description thereof is omitted.

  Therefore, in this embodiment, the discharge port (22) is at the compression end position of the piston (9) as much as possible by the notches (61), (61) of the overlap portion at both the upper and lower positions of the outer periphery of the piston (9). It becomes possible to delay the discharge start angle of the discharge valve (23), and the high pressure chamber (35) is discharged at the discharge end position of the piston (9) by the notches (61), (61). 22), the discharge of the fluid from the high pressure chamber (35) when the discharge valve (23) is fully closed can be performed efficiently, and the reactive power of the piston (9) is effectively reduced, and the swing compressor (1 ) Can be made more efficient.

  Next, Reference Technique 3 will be described with reference to FIGS. In this reference technique 3, the position where the notch is provided and the shape of the notch are changed.

  That is, in the present reference technique, as shown in FIGS. 8 and 9, each discharge port (22) is provided with a swing bush on the high pressure chamber (35) side of the blade (31) at the compression end position of the piston (9). (32) and the outer periphery of the cylinder (6) facing the outer periphery and the outer periphery of the piston (9) are provided so as to overlap when viewed from the axial direction of the cylinder (6). . The swing bush (32) overlaps with the discharge port (22) at both the upper and lower positions of the outer periphery and the cylinder (6) overlaps with the discharge port (22) at both the upper and lower positions of the peripheral portion and the piston. The overlap portion with the discharge port (22) at both the upper and lower positions of the outer peripheral portion includes each overlap portion so that the high pressure chamber (35) communicates with the discharge port (22) at the compression end position of the piston (9). A pair of upper and lower notches (71) in which the rocking bush (32) and the cylinder (6) both upper and lower positions of the rocking bush (32) and both positions of the piston outer periphery and upper and lower positions are cut into a conical shape across the span. (71) is provided. The rest of the configuration except for the notch (71) is the same as in the above embodiment, and the same parts are denoted by the same reference numerals and detailed description thereof is omitted.

  Therefore, in this embodiment, the overlap portion at both the upper and lower positions of the swing bush (32), the overlap portion at both the upper and lower positions of the cylinder (6), and the overlap at both the upper and lower positions of the piston (9) Each discharge port (22) is brought as close as possible to the compression end position of the piston (9) by the notches (71) and (71) straddling the lap portions, respectively, and the discharge start angle of the discharge valve (23) is increased. The fluid in the high-pressure chamber (35) is allowed to be delayed along the notches (71) and (71) on both the overlapping parts of the swing bush (32) and the cylinder (6). (22) is discharged smoothly, and at the compression end position of the piston (9), the discharge valve (23) is closed along the notches (71), (71) on the overlap part side of the piston (9). Efficiently discharges when turning off, and the reactive power of the piston (9) is more effectively reduced, further improving the efficiency of the swing compressor (1) Door can be.

  Each of the above reference techniques includes other various modifications. For example, in the reference technique 3 described above, notches (71) and (71) are provided over the overlapping portions of the swing bush (32), the cylinder (6) and the piston (9). When the overlap part of the cylinder occupies a larger proportion of the area of the overlap part with the outlet and the overlap part with the discharge port of the swinging bush, the overlap at both the upper and lower positions of the cylinder peripheral part It may be a pair of upper and lower cutouts that are cut out in a substantially conical shape so as to straddle only the overlap portions at both the upper and lower positions of the portion and the piston outer peripheral portion.

  In the above-described embodiment and reference technique, each discharge port (22) is formed in the front head (7) and the rear head (8), respectively, but the discharge port may be formed only in the front head.

  As described above, the present invention is useful for a swing compressor.

It is a cross-sectional top view of the compression end position vicinity of the piston cut | disconnected by the notch part vicinity which concerns on the reference technique 1. FIG. It is a vertical side view of the vicinity of the compression end position of the piston cut in the vicinity of the notch. It is the cross-sectional top view of the compression element similarly cut | disconnected near eccentric shaft part. It is a vertical side view of a swing compressor. FIG. 2 is a view corresponding to FIG. 1 according to the embodiment of the present invention. FIG. 3 is a view corresponding to FIG. Similarly, FIG. FIG. 3 is a view corresponding to FIG. Similarly, FIG.

Explanation of symbols

(1) Swing compressor
(5) Drive shaft
(5a) Eccentric shaft
(6) Cylinder
(6a) Cylinder chamber
(9) Piston
(10) Oil supply passage
(21) Suction port
(22) Discharge port
(24) Bush hole
(31) Blade
(32) Swing bush
(34) Low pressure chamber
(35) High pressure chamber
(41), (51), (61), (71) Notch

Claims (3)

A cylinder (6) having a cylinder chamber (6a) in which the suction port (21) and the discharge port (22) are opened; and
Side housings (7) arranged so as to close the cylinder chamber (6a) on both sides in the axial direction of the cylinder (6) and having the discharge port (22) formed on at least one of the both sides in the axial direction. (8) and
An annular piston (9) disposed in the cylinder chamber (6a) and having an inner peripheral portion rotatably fitted to an eccentric shaft portion (5a) of the drive shaft (5);
The cylinder (6a) is coupled to the outer peripheral portion of the piston (9) in a projecting manner, and is divided into a low pressure chamber (34) leading to the suction port (21) and a high pressure chamber (35) leading to the discharge port (22). Blade (31) to
A bush hole (24) having a circular cross section and penetrating the cylinder (6) in the axial direction, and a part thereof facing the cylinder chamber (6a) and opening to form an opening (24a);
A swinging bush (32) provided swingably in the bushing hole (24) of the cylinder (6) and supporting the protruding tip side of the blade (31) so as to be swingable and reciprocating;
As the drive shaft (5) rotates, the piston (9) revolves in the cylinder chamber (6a) with the swing bush (32) as a fulcrum through the blade (31). In the swing compressor (1) configured to compress the fluid sucked from the suction port (21) and discharge the fluid from the discharge port (22),
The discharge port (22) has a cylinder (6) with respect to a portion of the cylinder (6) protruding toward the opening (24a) and the swinging bush (32) sliding with the portion. The portion that overlaps the cylinder (6) occupies a larger area ratio than the portion that overlaps the swing bush (32),
Further, the discharge port (22) is provided at a position that does not overlap the blade (31) when viewed from the axial direction of the cylinder (6),
A notch (51) is provided only in the cylinder (6) of the cylinder (6) and the swing bush (32) that overlaps the discharge port (22),
The notch (51) is formed by notching the cylinder surface on the discharge port (22) side so that the high pressure chamber (35) communicates with the discharge port (22) at the compression end position of the piston (9). A swing compressor characterized by that. The swing compressor according to claim 1, wherein
The swing compressor is characterized in that the notch is formed so as to expand toward the discharge port (22) side. In the swing compressor according to claim 1 or 2,
The discharge port (22) is formed at a position where the area of the portion overlapping the cylinder (6) is not less than 4 times and not more than 9 times the area of the portion overlapping the swing bush (32). Swing compressor characterized by

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