JP2016017478A - Compressor - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a compressor capable of actualizing easy and reliable connection of a suction pipe to a casing, and still suppressing an increase in the pressure loss resulting from a sharp change in the flowing direction of fluid in a low pressure chamber.SOLUTION: A compressor (10) includes a suction pipe (15) passing through a casing (11) in the radial direction toward the center axis of a trunk part (12) of the casing (11) and fixed to the casing (11). In cylinders (51, 51a, 51b), suction ports (72, 72a, 72b) are formed which are communicated with the suction pipe (15), the outflow ends of which open to a cylinder chamber (55), and which have axial centers inclined to the axial center of the suction pipe (15) in the peripheral direction while extending toward the opposite side to a partition part (62), respectively.SELECTED DRAWING: Figure 3

Description

    The present invention relates to a compressor provided with a compression mechanism for compressing fluid, and relates to measures for reducing pressure loss of fluid sucked into a cylinder chamber.

    Conventionally, a compressor including a compression mechanism for compressing a fluid is known. For example, a compressor described in Patent Document 1 includes a casing having a cylindrical body, an electric motor fixed in the casing, a piston that is driven by the electric motor to perform a swinging motion, and a cylinder that houses the piston. And a swinging piston type compression mechanism. In the compression mechanism of Patent Document 1, the outer peripheral surface of the piston is formed in a non-circular shape, and the inner peripheral surface of the cylinder chamber in the cylinder is determined based on the envelope of the outer peripheral surface of the piston. A blade (partition) that divides the cylinder chamber into a high-pressure chamber and a low-pressure chamber is connected to the outer peripheral surface of the piston.

    In this compressor, when the drive shaft is rotationally driven by the electric motor, the piston performs a swinging motion in the cylinder chamber. Accordingly, the piston rotates (turns) in the cylinder chamber while forming a line contact (seal point) with the inner peripheral surface of the cylinder chamber. A suction port that communicates with the cylinder chamber is formed in the cylinder, and a suction pipe is connected to the suction port. When the volume of the low pressure chamber gradually increases with the rotation of the piston, fluid is sucked into the low pressure chamber from the suction port. When the piston further rotates from this state and the seal point passes through the suction port, the space that has been the low pressure chamber so far is blocked from the suction port, and becomes a high pressure chamber for compressing the fluid. When the piston further rotates from this state, the volume of the high pressure chamber gradually decreases, and the fluid in the high pressure chamber is compressed. Thus, when the pressure of the fluid in the high pressure chamber exceeds a predetermined value, the discharge valve is opened, and the fluid compressed to a high pressure is discharged to the outside of the compression mechanism.

JP 2011-241804 A

    By the way, the above-described compressor has a structure in which the suction pipe is passed through the casing body and the suction pipe is connected to the suction port. Here, it is preferable that the suction pipe penetrates the casing in the radial direction toward the central axis of the body portion of the casing. If the suction pipe is tilted and inserted into the casing with respect to the radial line connecting the outer peripheral surface of the casing body and the central axis, it becomes difficult to join the casing and the suction pipe (for example, brazing), which reduces the processing cost. This is because an increase or breakage of the connecting portion (for example, brazing crack) is likely to occur.

    On the other hand, in order to solve such a problem, if the suction pipe is configured to penetrate in the radial direction toward the central axis of the body portion of the casing, the position of the suction port to which the suction pipe is connected is restricted. Problems arise.

    Specifically, due to such restrictions, the outlet of the suction port in the cylinder is relatively close to the blade (partition) (for example, the imaginary line passing through the center of the drive shaft and the swing center of the blade and the shaft of the suction port). When the narrow angle with the center is relatively small), the fluid that has flowed into the low-pressure chamber so as to collide with the outer peripheral surface of the piston from the suction port is then along the outer peripheral surface of the piston or the inner peripheral surface of the cylinder chamber. Change the direction of flow rapidly. For this reason, in the low pressure chamber, there arises a problem that the pressure loss increases due to such a sudden change in the flow direction of the fluid.

    The present invention has been made in view of such a point, and an object of the present invention is to easily and reliably connect the suction pipe to the casing, and to reduce pressure loss caused by a sudden change in the flow direction of fluid in the low pressure chamber. It is providing the compressor which can suppress an increase.

    A first invention includes a casing (11) having a cylindrical body (12), an electric motor (20) fixed to an inner peripheral surface of the body (12) of the casing (11), and the electric motor ( 20), a piston (60, 60a, 60b), a cylinder (51, 51a, 51b) in which a cylinder chamber (55) for accommodating the piston (60, 60a, 60b) is formed; 51, 51 a, 51 b) for a compressor provided with a compression mechanism (50) having a partition part (62) that partitions a low pressure chamber (55 a) and a high pressure chamber (55 b), and the casing (11) The cylinder (51, 51a, 51b) includes a suction pipe (15) that passes through the casing (11) in a radial direction toward the central axis of the body (12) of the cylinder and is fixed to the casing (11). The outflow end communicates with the suction pipe (15) and opens to the cylinder chamber (55), and faces toward the opposite side of the partition (62) with respect to the axial center of the suction pipe (15). Suction port having inclined axis in a circumferential direction (72, 72a, 72b), characterized in that is formed.

    In the first invention, in the first invention, the piston (60, 60a, 60b) driven by the electric motor (20) is rotationally driven in the cylinder chamber (55), so that the volume of the low pressure chamber (55a) is increased. As the pressure increases, the volume of the high pressure chamber (55b) decreases, and the fluid is compressed by the compression mechanism (50).

    The suction pipe (15) penetrates the casing (11) in the radial direction toward the central axis of the body (12) of the casing (11). For this reason, joining of a casing (11) and a suction pipe (15) is performed easily and reliably. On the other hand, as described above, the outlet of the suction port (72, 72a, 72b) is positioned relatively far from the partition (62), and the flow direction of the fluid in the low pressure chamber (55a) changes as described above. Will become bigger.

    On the other hand, in the present invention, the shaft centers of the suction ports (72, 72a, 72b) are inclined in the circumferential direction toward the partition portion (62) with respect to the shaft center of the suction pipe (15). As a result, the fluid flowing into the low pressure chamber (55a) from the suction port (72, 72a, 72b) is low pressure along the outer peripheral surface of the piston (60, 60a, 60b) or the inner peripheral surface of the cylinder chamber (55). Flows through chamber (55a). Therefore, the change in the flow direction of the fluid in the low pressure chamber (55a) can be reduced.

    According to a second invention, in the first invention, the cylinder (51, 51a, 51b) is formed with a connection port (81, 81a, 81b) through which the suction pipe (15) is inserted, and the suction port (72, 72a, 72b) communicates with the outflow end of the connection port (81, 81a, 81b), and the axis of the suction port (72, 72a, 72b) is connected to the connection port (81, 81a, 81b). ) In the circumferential direction toward the opposite side of the partition part (62).

    In the second invention, the axial center of the connection port (81, 81a, 81b) to which the suction pipe (15) is connected is defined by the partition (62) with respect to the axial center of the suction port (72, 72a, 72b). It is inclined in the circumferential direction toward the opposite side. Thereby, the outflow port of a suction port (72, 72a, 72b) leaves | separates from a partition part (62).

    According to a third invention, in the second invention, the cylinder (51, 51a, 51b) includes a cylinder body (70, 70a, 70b) in which the suction port (72, 72a, 72b) is formed, and the cylinder It has a connection member (80) attached to the main body (70, 70a, 70b) and formed with the connection port (81, 81a, 81b).

    The cylinder (51, 51a, 51b) of the third invention is provided with a cylinder body (70, 70a, 70b) and a connecting member (80) which are configured separately from each other. The connection member (80) is formed with a connection port (81, 81a, 81b) to which the suction pipe (15) is connected, and the cylinder body (70, 70a, 70b) has a suction port (72, 72a, 72b). ) Is formed. Thereby, the axis of the suction port (72, 72a, 72b) can be easily tilted with respect to the axis of the connection port (81, 81a, 81b).

    In a fourth aspect based on the third aspect, the connection member (80) has an inflow end connected to the connection port (81, 81a, 81b) and an outflow end connected to the suction port (72, 72a, 72b). ) And a bent port portion (83) bent so as to be coaxial with the suction port (72, 72a, 72b) with respect to the axis of the connection port (81, 81a, 81b). It is characterized by being.

    In the fourth invention, in the fourth invention, a bending port portion (83) for tilting the axis between the suction pipe (15) and the suction ports (72, 72a, 72b) is formed in the connection member (80). Is done.

    In a fifth aspect based on the third aspect, the cylinder body (70, 70a, 70b) has an inflow end connected to the connection port (81, 81a, 81b) and an outflow end connected to the suction port (72 72a, 72b) and a bent port portion (73) bent to be coaxial with the suction port (72, 72a, 72b) with respect to the axial center of the connection port (81, 81a, 81b) Is formed.

    In the fifth invention, the bending port portion (73) for inclining the axis between the suction pipe (15) and the suction port (72, 72a, 72b) is formed in the cylinder body (70, 70a, 70b). .

  According to a sixth invention, in any one of the second to fifth inventions, the connection port (81, 81a, 81b) has an inner diameter of the connection port (81, 81a, 81b). 72a, 72b) is configured to be larger than the inner diameter.

    In the sixth invention, since the inner diameter of the connection port (81, 81a, 81b) is larger than the inner diameter of the suction port (72, 72a, 72b), the suction pipe (15) having a relatively large diameter is connected to the connection port (81 81a, 81b), the thickness of the cylinder (51, 51a, 51b) can be reduced.

    In a seventh aspect based on the sixth aspect, the length of the connection port (81, 81a, 81b) is L, the inner diameter of the connection port (81, 81a, 81b) is D, and the suction port (72, 72a 72b) where d is the inner diameter of the connection port (81, 81a, 81b) and α is the inclination angle of the suction port (72, 72a, 72b) with respect to the axis of the connection port (81, 81a, 81b). 51b) is characterized in that it is configured to satisfy the relational expression D ≧ (d / cos α) + (L × tan α).

    In the seventh invention, by satisfying the above relational expression, the connection ports (81, 81a, 81b) having the inner diameter D and the length L are formed without breaking, and further the suction ports (72, 72a, 72b) can be formed inside the cylinder (51, 51a, 51b).

      According to an eighth invention, in any one of the first to seventh inventions, an inner peripheral shape of the suction port (72, 72a, 72b) is flat in a thickness direction of the cylinder (51, 51a, 51b). It is characterized by being formed in an elliptical shape.

    In the eighth invention, the inner peripheral shape of the suction port (72, 72a, 72b) is formed in an elliptical shape that is flat in the thickness direction of the cylinder (51, 51a, 51b). For this reason, even if it is the structure where the thickness of a cylinder (51,51a, 51b) is comparatively small, the flow-path cross-sectional area of a suction port (72,72a, 72b) is securable.

    According to a ninth invention, in any one of the first, second, and fourth to eighth inventions, the piston (60, 60a, 60b) has an outer peripheral surface formed in a non-circular shape, and performs a swinging motion. The cylinder (51, 51a, 51b) is configured such that the inner peripheral surface of the cylinder chamber (55) has an envelope of the outer peripheral surface of the piston (60, 60a, 60b) that performs the swing motion. The partition portion (62) is configured by a blade (62) connected to the outer peripheral surface of the piston (60, 60a, 60b).

    In the ninth invention, the outer peripheral surface of the piston (60, 60a, 60b) and the inner peripheral surface of the cylinder chamber (55) are formed in a non-circular shape, and the piston (60, 60a, 60b) is formed in the cylinder chamber (55). Oscillate along That is, the compression mechanism (50) is configured as a non-circular swinging piston type.

    In a tenth aspect based on the third aspect, the piston (60, 60a, 60b) has a non-circular outer peripheral surface and is configured to perform a swinging motion. The cylinder (51, 51a, 51b) is configured such that the inner peripheral surface of the cylinder chamber (55) has a non-circular shape based on an envelope of the outer peripheral surface of the piston (60, 60a, 60b) that performs the swinging motion. (62) is composed of a blade (62) connected to the outer peripheral surface of the piston (60, 60a, 60b), and the cylinder body (70, 70a, 70b) is composed of the cylinder body (70, 70a, 70b). The axial length of the connecting member (80) is smaller than the axial length of the cylinder body (70, 70a, 70b), and the connecting port (81, 81a, 81b) , 81a, 81b) is configured to be larger than the inner diameter of the suction port (72, 72a, 72b).

    In the tenth invention, the compression mechanism (50) is configured as a non-circular swinging piston type. In the non-circular oscillating piston type compression mechanism (50), the piston (60, 60a, 60b) and the cylinder (51, 51a, 51b) are formed relatively wide, while the piston (60, 60a, 60b) ) And cylinders (51, 51a, 51b) have a relatively small axial length (thickness). For this reason, the inner diameter of the suction port (72, 72a, 72b) formed in the cylinder body (70, 70a, 70b) is also relatively small, and it is difficult to connect the suction pipe (15) having a relatively large outer diameter. On the other hand, in the present invention, the axial length of the cylinder body (70, 70a, 70b) in the connecting member (80) separate from the cylinder body (70, 70a, 70b) is determined by the cylinder body (70, 70a). , 70b). And the internal diameter of the connection port (81, 81a, 81b) formed in the connection member (80) is made larger than the suction port (72, 72a, 72b). Therefore, the suction pipe (15) having a relatively large outer diameter can be connected to the connection member (80), and the cylinder body (70, 70a, 70b) has a relatively thin cylinder (51, 51a). , 51b), a relatively small-diameter suction port (72, 72a, 72b) can be formed.

    According to the first invention, the axis of the suction port (72, 72a, 72b) is inclined toward the partition (62) with respect to the axis of the suction pipe (15). It is possible to suppress a change in the flow direction of the fluid flowing into 55a). As a result, the fluid can smoothly flow into the low pressure chamber (55a), and an increase in pressure loss in the low pressure chamber (55a) can be avoided.

    Further, since the suction pipe (15) is configured to penetrate in the radial direction toward the axial center of the casing (11), the suction pipe (15) can be easily connected to the casing (11). Therefore, the processing cost can be reduced. Further, it is possible to prevent the connection portion between the suction pipe (15) and the casing (11) from being damaged, and to improve the reliability of the compressor.

    According to the second invention, the connection port (81, 81a, 81b) to which the suction pipe (15) is connected is inclined with respect to the suction port (72, 72a, 72b). The effect of this can be achieved.

    In the third invention, the cylinder (51, 51a, 51b) has a cylinder body (70, 70a, 70b) having a suction port (72, 72a, 72b) and a connection having a connection port (81, 81a, 81b). Since it is configured separately from the member (80), the axes of both ports (72, 81) can be easily tilted.

    According to the sixth aspect of the invention, the suction pipe (15) having a relatively large outer diameter or inner diameter can be used, and the pressure loss can be reduced.

    According to the seventh invention, the suction ports (72, 72a, 72b) having the inner diameter d are connected to the cylinders (51, 51a, 72b) without breaking the shape of the connection ports (81, 81a, 81b) having the inner diameter D and the length L. 51b) can be vacated inside.

    According to the eighth aspect of the invention, even if the cylinder (51, 51a, 51b) has a relatively small thickness, the flow passage cross-sectional area of the suction port (72, 72a, 72b) can be secured, and the pressure loss can be reduced. Can be reduced.

    According to the ninth invention, in the compressor using the non-circular rocking piston type compression mechanism (50), the effects of the first, second and fourth to eighth inventions described above are exhibited. Can do.

    According to the tenth aspect of the present invention, the suction port (72, 72a, 72b) having a small inner diameter is used while connecting the relatively outer diameter pipe to the connection port (81, 81a, 81b) of the connection member (80). The axial length (thickness) of the cylinder body (70, 70a, 70b) can be reduced.

FIG. 1 is a longitudinal sectional view of a compressor according to an embodiment. FIG. 2 is an enlarged longitudinal sectional view of a main part of the compression mechanism and the drive shaft according to the embodiment. 3 is a cross-sectional view taken along the line XX of FIG. FIG. 4 is a configuration diagram schematically showing the dimensions and relative positional relationship between the connection port and the suction port. FIG. 5 is a view corresponding to FIG. 3 for explaining the operation of the compressor. FIG. 5 (A) shows a state where the piston is located near the top dead center, and FIG. FIG. 5C shows a state immediately after being shut off from the suction port, FIG. 5C shows a state where the piston is located near the bottom dead center, and FIG. 5D shows a state where the piston is located near the rotation angle 270. Is. FIG. 6 is a view corresponding to FIG. 2 of a compressor according to a modification. FIG. 7 is an enlarged perspective view of a main part of a compression mechanism according to a modification. FIG. 8 is a diagram corresponding to FIG. 3 of the first example according to another embodiment. FIG. 9 is a front view of the vicinity of the suction port as viewed from the inside of the cylinder chamber. FIG. 10 is a diagram corresponding to FIG. 3 of the second example according to another embodiment.

    Hereinafter, embodiments of the present invention will be described in detail with reference to the drawings. The following embodiments are essentially preferable examples, and are not intended to limit the scope of the present invention, its application, or its use.

<Overall configuration of compressor>
FIG. 1 is a longitudinal sectional view of a compressor (10) according to the present embodiment. The compressor (10) according to the present embodiment is a hermetically sealed oscillating piston type compressor. The compressor (10) is connected to a refrigerant circuit (not shown) filled with a refrigerant. In the refrigerant circuit, a vapor compression refrigeration cycle is performed. That is, in the refrigerant circuit, the refrigerant compressed by the compressor (10) is condensed by the condenser, depressurized by the expansion valve, evaporated by the evaporator, and sucked into the compressor (10).

    The compressor (10) includes a casing (11), an electric motor (20) accommodated in the casing (11), a drive shaft (30) connected to the electric motor (20), and the drive shaft (30). And a driven compression mechanism (50).

<casing>
The casing (11) is a vertically long cylindrical sealed container. The casing (11) has a trunk (12), a lower end plate (13), and an upper end plate (14). The trunk portion (12) is formed in a cylindrical shape extending vertically, and both ends in the axial direction are open. The lower end plate (13) is fixed to the lower end of the body (12). The upper end plate (14) is fixed to the upper end of the body (12).

    A suction pipe (15) is fixed through the lower portion of the body (12). A discharge pipe (16) passes through and is fixed to the upper end plate (14). A terminal (17) for supplying electric power to the electric motor (20) is attached to the upper end plate (14).

    An oil reservoir (18) is formed at the bottom of the casing (11). The oil reservoir (18) is constituted by the lower end plate (13) and the lower inner wall of the body (12). Lubricating oil (refrigeration machine oil) for lubricating the sliding parts of the compression mechanism (50) and the drive shaft (30) is stored in the oil storage part (18).

    The inside of the casing (11) is filled with the high-pressure refrigerant compressed by the compression mechanism (50). That is, the compressor (10) has a so-called high-pressure dome shape in which the internal pressure of the casing (11) is substantially equal to the pressure of the high-pressure refrigerant.

<Electric motor>
The electric motor (20) is disposed above the compression mechanism (50). The electric motor (20) has a stator (21) and a rotor (22). The stator (21) is fixed to the inner peripheral surface of the body (12) of the casing (11). The rotor (22) penetrates the interior of the stator (21) in the vertical direction. A drive shaft (30) is fixed inside the shaft center of the rotor (22). When the electric motor (20) is energized, the drive shaft (30) is rotationally driven together with the rotor (22).

<Drive shaft>
The drive shaft (30) is located on the axial center (one-dot chain line C1 in FIG. 1) of the body (12) of the casing (11). The drive shaft (30) is rotatably supported by bearings (41, 42, 43) (details will be described later) of the compression mechanism (50).

    The drive shaft (30) has a main shaft (31), a crank shaft (32), and a sub shaft (33) in order from the upper side to the lower side. The upper part of the main shaft (31) is fixed to the rotor (22) of the electric motor (20). The crankshaft (32) is connected to the lower end of the main shaft (31). The countershaft (33) is connected to the lower end of the crankshaft (32). The axis (C1 in FIG. 1) of the main shaft (31) and the sub shaft (33) coincide. The axis C2 of the crankshaft (32) is eccentric by a predetermined amount with respect to the axis C1 of the main shaft (31) and the sub shaft (33). The outer diameter of the crankshaft (32) is larger than the outer diameters of the main shaft (31) and the sub shaft (33).

    The upper part of the main shaft (31) is fixed to the rotor (22) of the electric motor (20). The lower part of the main shaft (31) is located inside the main shaft side through hole (52c) of the front head (52). An intermediate portion in the axial direction of the main shaft (31) is rotatably supported by the upper main bearing (41). The lower part of the main shaft (31) is rotatably supported by the lower main bearing (42). The upper part of the countershaft (33) is located inside the countershaft side through hole (53a) of the rear head (53). An intermediate portion of the auxiliary shaft (33) in the axial direction is rotatably supported by the auxiliary bearing (43).

    As shown in FIG. 2, the drive shaft (30) includes an oil supply mechanism (34) for supplying oil around the crankshaft (32). The oil supply mechanism (34) includes an oil pump (35) attached to the lower end of the auxiliary shaft (33), a main flow path (36) extending along the center of the drive shaft (30), and the main flow path ( 36) and three branch channels (37, 38, 39) branching radially outward.

    The oil pump (35) conveys the oil accumulated in the oil reservoir (18) to the main channel (36). As the oil pump (35), various pumps such as a differential pressure type, a centrifugal type, and a positive displacement type can be adopted. The main channel (36) has an inflow end connected to the oil pump (35), and guides the lubricating oil conveyed by the oil pump (35) upward.

    The three branch channels (37, 38, 39) are a lower branch channel (37), an intermediate branch channel (38), and an upper branch channel in order from the lower side to the upper side of the drive shaft (30). (39). The lower branch channel (37) is formed inside the upper end portion of the auxiliary shaft (33). The inflow end of the lower branch flow path (37) is connected to the main flow path (36), and the outflow end of the lower branch flow path (37) is open toward the sub bearing (43). The intermediate branch channel (38) is formed inside the crankshaft (32). The inflow end of the lower branch flow path (37) is connected to the main flow path (36), and the outflow end of the lower branch flow path (37) is the inner peripheral surface side of the piston (60) (strictly, the annular metal (59) Of the inner peripheral surface side). The upper branch channel (39) is formed inside the lower end of the main shaft (31). The inflow end of the upper branch flow path (39) is connected to the main flow path (36), and the outflow end of the upper branch flow path (39) is open toward the lower main bearing (42).

<Compression mechanism>
As shown in FIG.1 and FIG.2, the compression mechanism (50) is arrange | positioned under the electric motor (20). The compression mechanism (50) is configured as a non-circular swinging piston type. The compression mechanism (50) includes a cylinder (51), a front head (52), and a rear head (53). In the compression mechanism (50), the front head (52) is stacked on the upper end (one axial end) of the cylinder (51), and the rear head (53) is disposed on the lower end (other axial end) of the cylinder (51). Laminated. The cylinder (51), the front head (52), and the rear head (53) are integrated via a fastening member (not shown). The front head (52) and the rear head (53) constitute a head member.

    The cylinder (51) is fixed to the inner peripheral surface of the lower portion of the body (12) of the casing (11). The cylinder (51) has a flat and substantially annular cylinder body (70) and a connecting member (80) attached to the outer peripheral surface of the cylinder body (70).

    A cylindrical cylinder chamber (55) is formed at the center of the cylinder body (70). As shown in FIGS. 1 and 3, the cylinder body (70) is formed with a suction port (72) extending in the radial direction. A connection port (81) to which the outflow part of the suction pipe (15) is connected is formed in the connection member (80). The suction pipe (15) communicates with the cylinder chamber (55) via the connection port (81) and the suction port (72).

    The front head (52) is disposed above the cylinder (51) so as to cover the internal space of the cylinder (51). The front head (52) includes a flat annular plate portion (52a) stacked on the cylinder (51) and a cylindrical projecting portion (52b) projecting upward from the radial center of the annular plate portion (52a). Have. The front head (52) is formed with a discharge port (57) passing through the annular plate portion (52a) in the axial direction (see FIG. 3). The inflow end of the discharge port (57) communicates with the cylinder chamber (55) (high pressure chamber (55b)). A reed valve (not shown) is provided at the outflow end of the discharge port (57).

    In the front head (52), a main shaft side through hole (52c) through which the main shaft (31) passes is formed at the center of the annular plate portion (52a) and the cylindrical protrusion (52b). An upper main bearing (41) is formed on the inner peripheral surface of the upper end portion of the main shaft side through hole (52c). A lower main bearing (42) is formed below the main shaft side through hole (52c).

    The rear head (53) is disposed below the cylinder (51) so as to cover the internal space of the cylinder (51). At the center in the radial direction of the rear head (53), a sub-shaft side through-hole (53a) through which the sub-shaft (33) passes is formed. A sub bearing (43) is formed on the inner peripheral surface of the sub shaft side through hole (53a).

    As shown in FIG. 3, the compression mechanism (50) of the present embodiment constitutes a so-called non-circular oscillating piston type compression mechanism. Specifically, the compression mechanism (50) includes an annular metal (59), a piston (60), a bush (61), and a blade (62). The piston (60) is accommodated in the cylinder chamber (55).

    The annular metal (59) is formed of a cylindrical metal member fixed inside the piston (60) by press fitting or the like. The annular metal (59) is externally fitted to the crankshaft (32) so that the inner peripheral surface thereof is in sliding contact with the outer peripheral surface of the crankshaft (32). The annular metal (59) has a higher hardness than the piston (60).

    The crankshaft (32) is fitted inside the piston (60) via an annular metal (59). The piston (60) of this embodiment has a non-circular outer peripheral surface. Specifically, on the outer peripheral surface of the piston (60), the portions on both sides sandwiching the virtual vertical plane (P in FIG. 3) passing through the longitudinal center line of the blade (62) bulge outward in the radial direction. It is formed in such a substantially elliptical shape or a substantially egg shape.

    On the other hand, the inner peripheral surface shape of the cylinder chamber (55) of the cylinder (51) is formed in a non-circular shape corresponding to the outer peripheral surface shape of the piston (60). That is, the inner peripheral surface shape of the cylinder chamber (55) is formed in a non-circular shape such that the portions on both sides of the virtual vertical plane P passing through the blade (62) bulge outward in the radial direction. . That is, the inner peripheral surface shape of the cylinder chamber (55) is formed in a non-circular shape based on the envelope of the outer peripheral surface of the piston (60) that performs the swinging motion.

    A substantially circular bush groove (63) is formed in the cylinder (51) at a position adjacent to the cylinder chamber (55). A pair of substantially semicircular bushes (61, 61) are fitted in the bush groove (63). The pair of bushes (61, 61) are arranged in the bush groove (63) so that the flat surfaces thereof face each other. The pair of bushes (61, 61) is configured to swing around the axis of the bush groove (63).

    The blade (62) is formed in a rectangular parallelepiped shape or a plate shape extending radially outward. The base end of the blade (62) is connected to the outer peripheral surface of the piston (60). The blade (62) is accommodated in a blade groove (64) formed between the pair of bushes (61, 61) so as to advance and retreat.

    The blade (62) constitutes a partition that divides the cylinder chamber (55) into a low pressure chamber (55a) and a high pressure chamber (55b). The low pressure chamber (55a) is a space on the right side of the blade (62) in FIG. 3 and communicates with the suction port (72). The high pressure chamber (55b) is a space on the left side of the blade (62) in FIG. 3, and communicates with the discharge port (57).

<Detailed structure of cylinder and suction pipe and surrounding area>
As shown in FIG. 3, the suction pipe (15) passes through the body (12) of the casing (11) in the radial direction and is fixed to the casing (11). The suction pipe (15) is configured such that the axis C3 of the suction pipe (15) passes through the center of the trunk (12) (axial center C1 of the drive shaft). That is, the axis C3 of the suction pipe (15) is orthogonal to the horizontal tangent to the outer peripheral surface of the body (12) of the casing (11). Thereby, the suction pipe (15) can be easily brazed to the casing (11), and the mounting strength of the suction pipe (15) and the casing (11) is improved.

    Further, in the suction pipe (15) of the present embodiment, the large-diameter portion (15a), the reduced-diameter portion (15b), and the small-diameter portion (15c) are successively arranged from the upstream side to the downstream side of the refrigerant flow. Configured. The inner diameter of the large diameter portion (15a) is larger than the inner diameter of the small diameter portion (15c), and the outer diameter of the large diameter portion (15a) is smaller than the outer diameter of the small diameter portion (15c). The reduced diameter portion (15b) is formed in a tapered shape that gradually reduces its outer diameter and inner diameter toward the downstream side.

      As shown in FIG. 3, a planar flat portion (71) is formed in the vicinity of the outflow portion of the suction pipe (15) on the outer peripheral surface of the cylinder body (70). A connecting member (80) is attached to the flat portion (71) via a fastening member (not shown).

    The connecting member (80) includes a flat plate portion (80a) in contact with the flat portion (71) and an inner peripheral surface of the body portion (12) of the casing (11) from an intermediate portion of the substrate portion (80a). And a connecting portion main body (80b) protruding toward the front. The connection portion main body (80b) is formed in a substantially rectangular parallelepiped shape. The radially outer surface of the connection portion main body (80b) forms an arc surface along the inner peripheral surface of the trunk portion (12).

    A connection port (81), a relay port (82), and an outflow port (83) are successively formed on the connection member (80) in order from the radially outer side to the inner side of the cylinder (51). ing. The cross-sectional shapes of the suction port (72), the relay port (82), and the outflow port (83) are circular.

    The inner diameter of the connection port (81) is approximately equal to the outer diameter of the small diameter portion (15c) of the suction pipe (15). The small diameter portion (15c) of the suction pipe (15) is connected to the connection port (81). The relay port (82) is formed in a tapered shape that gradually reduces its inner diameter toward the downstream side. The outflow port (83) has a bent port portion whose axis C4 bends in the circumferential direction (rotation direction of the piston (60)) toward the opposite side of the blade (62) with respect to the axis C3 of the suction pipe (15). Is configured.

    The suction port (72) communicates with the suction pipe and has an outflow end opened to the cylinder chamber (55). The cross-sectional shape of the flow path of the suction port (72) is circular. The suction port (72) has an axial center C4 coaxial with the outflow port (83). That is, the axial center C4 of the suction port (72) is circumferentially directed toward the opposite side of the blade (62) with respect to the axial center C3 of the suction pipe (15) (that is, the axial center C3 of the connection port (81)). It is inclined in the direction of rotation of the piston (60).

    The relationship between the connection port (81) and the suction port (72) will be described in more detail with reference to the schematic diagram of FIG. In the present embodiment, the inner diameter D of the connection port (81) is larger than the inner diameter d of the suction port (72). Here, the cylinder (51) has the following relational expression so that the suction port (72) with the inner diameter d can be formed so as not to break the shape of the connection port (81) with the inner diameter D and the axial length L. It is configured to satisfy.

    First, the length D1 shown in FIG. 4 is expressed by the following equation.

D1 = d / cos α (1)
Here, α is an inclination angle between the axis C3 of the connection port (81) and the axis C4 of the suction port (72).

    Moreover, the length D2 shown in FIG. 4 is represented by the following formula.

D2 = L × tan α (2)
For this reason, in order to form the connection port (81) without breaking the inner diameter D and the length L,
D ≧ D1 + D2 = (d / cos α) + (L × tan α) (3) may be satisfied. As a result, in the cylinder (51), it is possible to form a cylindrical suction port (72) having an inner diameter d while forming a cylindrical connection port (81) having an inner diameter D and a length L.

−Operation of compressor−
The basic operation of the compressor (10) will be described with reference to FIGS. When electric power is supplied from the terminal (17) to the electric motor (20), the electric motor (20) is operated, and the drive shaft (30) is rotationally driven. Then, the crankshaft (32) of the drive shaft (30) rotates eccentrically, and the piston (60) performs a swinging motion along with this.

    In the compression mechanism (50), the outer peripheral surface of the piston (60) is in line contact with the inner peripheral surface of the cylinder chamber (55) via the oil film to form a seal portion. When the piston (60) oscillates in the cylinder chamber (55), the seal portion between the piston (60) and the cylinder (51) (for example, point a, point b, point c, point d in FIG. 5). However, it is displaced along the inner peripheral surface of the cylinder chamber (55), and the volumes of the low pressure chamber (55a) and the high pressure chamber (55b) change. At this time, the blade (62) moves back and forth in the blade groove (64) with the swinging motion of the piston (60), and swings about the axis of the bush groove (63).

    When the volume of the low pressure chamber (55a) gradually increases with the swinging motion of the piston (60) (FIG. 5 (A) → FIG. 5 (B) → FIG. 5 (C) → FIG. 5 (D)), the suction pipe The fluid (refrigerant) flowing through (15) is drawn into the low pressure chamber (55a) from the suction port (72). Next, when the low pressure chamber (55a) is blocked from the suction port (72) (state of FIG. 5B), the blocked space constitutes the high pressure chamber (55b). Next, when the volume of the high pressure chamber (55b) gradually decreases (FIG. 5B → FIG. 5C → FIG. 5D), the internal pressure of the high pressure chamber (55b) increases. When the internal pressure of the high pressure chamber (55b) exceeds a predetermined pressure, the reed valve of the discharge port (57) is opened, and the refrigerant in the high pressure chamber (55b) passes through the discharge port (57) to the outside of the compression mechanism (50). leak. This high-pressure refrigerant flows upward in the internal space of the casing (11) and passes through a core cut (not shown) of the electric motor (20). The high-pressure refrigerant that has flowed out of the electric motor (20) is sent from the discharge pipe (16) to the refrigerant circuit.

<Lubrication oil supply operation>
When the drive shaft (30) is rotationally driven during the operation of the compressor (10), the oil accumulated in the oil reservoir (18) is conveyed to the main flow path (36) (see FIG. 2). This oil flows upward in the main flow path (36) of the drive shaft (30).

    The oil in the main channel (36) is divided into each branch channel (37, 38, 39). Specifically, the oil branched into the lower branch flow path (37) is supplied to the sliding portion of the auxiliary bearing (43) and used for lubrication of the sliding portion. The oil branched into the upper branch flow path (39) is supplied to the sliding portion of the lower main bearing (42) and used for lubrication of the sliding portion.

    The oil divided into the intermediate branch channel (38) is supplied to the sliding part between the inner peripheral surface of the annular metal (59) and the outer peripheral surface of the crankshaft (32) and used for lubrication of the sliding part. Is done. This oil further flows into the gap between the axial end surfaces of the piston (60) (upper and lower end surfaces of the piston (60)) and the head members (front head (52) and rear head (53). , An oil film seal is formed in the gap between the piston (60) and the head member (51, 53), and this oil flows radially outward in the gap and flows out into the cylinder chamber (55). 60) is used for oil film sealing and lubrication at the contact portion between the cylinder (51) and discharged from the discharge port (57) to the outside of the compression mechanism (50) together with the refrigerant.

-Action and effect of suction port-
In the compressor (10) of the present embodiment, as shown in FIG. 3, the suction pipe is arranged such that the axis C3 of the suction pipe (15) passes through the central axis C1 of the body (12) of the casing (11). (15) penetrates the casing (11) in the radial direction. As a result, as described above, the brazing process between the suction pipe (15) and the casing (11) is facilitated, and due to the brazing crack between the suction pipe (15) and the casing (11). It is also possible to avoid damage to the connecting part.

      On the other hand, the suction pipe (15) is penetrated in the radial direction toward the central axis C1 of the casing (11) in this way, and the axis C3 of the suction pipe (15) and the axis C4 of the suction port (72) are coaxial. If it comprises, the outflow port of a suction port (72) will be located comparatively near with respect to a braid | blade (62) thru | or bush (61). As a result, during the operation of the compressor (10) described above, the flow direction of the refrigerant flowing inward in the radial direction from the suction port (72) toward the low pressure chamber (55a) rapidly changes in the circumferential direction. End up. As a result, there arises a problem that the pressure loss of the refrigerant flowing into the low pressure chamber (55a) is increased.

    Therefore, in the present embodiment, as shown in FIG. 3, the axis C4 of the suction port (72) is bent to the opposite side of the blade (62) by the inclination angle α with respect to the axis C3 of the suction pipe (15). Yes. For this reason, in the compression mechanism (50), the angle at which the flow of the refrigerant flowing into the low pressure chamber (55a) from the suction port (72) changes is smaller than that of the configuration of the comparative example described above. Therefore, for example, as shown in FIGS. 5C and 5D, this refrigerant smoothly flows in the circumferential direction in the low-pressure chamber (55a), so that an increase in pressure loss can be avoided.

    In the present embodiment, a non-circular oscillating piston type compression mechanism (50) is used. In this compression mechanism (50), the piston (60) and the cylinder (51) are likely to expand horizontally, and their thickness is relatively reduced accordingly. Therefore, it is difficult to directly connect the suction pipe (15) having a relatively large diameter to the suction port (72) of the cylinder (51). On the other hand, in this embodiment, the cylinder (51) is separated into the cylinder body (70) and the connection member (80), and the height of the connection member (80) (the connection member in the axial direction of the cylinder (51)). (Length of (80)) is larger than the height of the cylinder body (70) (length in the axial direction of the cylinder (51)). The connection member (80) is formed with a connection port (81) having a larger inner diameter than the suction port (72). Accordingly, the suction pipe (15) having a relatively large diameter can be communicated with the suction port (72) while suppressing the height of the cylinder (51) to a necessary minimum.

    Furthermore, in this embodiment, the cylinder (51) is configured to satisfy the above expression (3) (see FIG. 4). As a result, in the cylinder (51), it is possible to form a cylindrical suction port (72) having an inner diameter d while forming a cylindrical connection port (81) having an inner diameter D and a length L. As a result, in the cylinder (51), a relatively large-diameter suction pipe (15) can be connected with the insertion allowance L, and the suction port (72) is inclined by α with respect to the suction pipe (15). Can be obtained.

<< Modification of Embodiment >>
The compression mechanism (50) according to the embodiment includes a one-cylinder compression mechanism (50) having one cylinder (51) and one piston (60). However, as shown in FIG. 6, the compression mechanism (50) includes a plurality (two in this example) of cylinders (51a, 51b) and a plurality (two in this example) of pistons (60a, 60b). And a multi-cylinder compression mechanism (50).

    Specifically, in the compression mechanism (50) according to the modification, the front head (52), the first cylinder (51a), the annular middle plate (58), and the second cylinder (51b) are sequentially arranged from the upper side to the lower side. ), A rear head (53) is laminated. The first piston (60a) is accommodated in the cylinder chamber (55) of the first cylinder (51a), and the second piston (60b) is accommodated in the cylinder chamber (55) of the second cylinder (51b). Yes. A first crankshaft (32a) is fitted into the first piston (60a) via a first annular metal (59a), and a second piston (60b) is interposed via a second annular metal (59b). The second crankshaft (32b) is fitted inside. A bush (61), a blade (62), a bush groove (63), and a blade groove (64) are provided inside the first cylinder (51a) and the second cylinder (51b) in the same manner as in the above embodiment. (See FIG. 3).

    As shown in FIGS. 6 and 7, in this modification, the connection member (80) is shared by both the first cylinder (51a) and the second cylinder (51b). That is, the connecting member (80) is a vertically long connecting portion main body (80b) straddling both the cylinder main body (70a) of the first cylinder (51a) and the cylinder main body (70b) of the second cylinder (51b). have. A first connection port (81a) to which the first suction pipe (15) is connected is formed in the upper part of the connection part body (80b), and a second suction pipe is formed in the lower part of the connection part body (80b). A second connection port (81b) to which (15) is connected is formed. Each suction pipe (15) penetrates the trunk portion (12) of the casing (11) in the radial direction toward the central axis C1 of the trunk portion (12) of the casing (11).

    The cylinder body (70a) of the first cylinder (51a) has an axis C4 inclined to the opposite side of the blade (62) with respect to the axis C3 of the first suction pipe (15), as in the above embodiment. A first suction port (72a) is formed. The cylinder body (70b) of the second cylinder (51b) has an axis C4 inclined to the opposite side of the blade (62) with respect to the axis C3 of the second suction pipe (15), as in the above embodiment. A second suction port (72b) is formed.

    Therefore, also in this modified example, the joining process between the casing (11) and each suction pipe (15) can be facilitated, the connection strength can be improved, and the pressure loss of the refrigerant flowing into the low pressure chamber (55a) can be reduced. .

<< Other Embodiments >>
About the said embodiment, it is good also as the following structures.

    In the above embodiment, the outflow port (83) constituting the bending port portion is formed inside the connection member (80), and the angles of the axes of the suction pipe (15) and the suction port (72) are shifted. . However, as shown in FIG. 8, for example, a bent port portion (inflow port (73)) is formed inside the cylinder body (70), and is coaxial with the inflow port (73) at the downstream end of the inflow port (73). The suction port (72) may be connected to shift the angle between the axes of the suction pipe (15) and the suction port (72).

    In addition, the suction port (72) of the above embodiment has a circular channel cross-sectional shape. However, for example, as shown in FIG. 9, the shape of the outflow end of the suction port (72) may be formed in an elliptical shape that is flat in the thickness direction of the cylinder (51). As a result, the flow passage cross-sectional area of the suction port (72) can be made relatively large while the height of the cylinder (51) is kept relatively small.

    In the compression mechanism (50) according to the above-described embodiment, the outer peripheral surface of the piston (60) is expanded radially outwardly on both sides of the virtual vertical plane P passing through the blade (62) in the longitudinal direction. It has a non-circular shape as shown (see FIG. 3). However, for example, as shown in FIG. 10, the outer peripheral surface of the piston (60) is such that one of the parts on both sides sandwiching the virtual vertical plane P (the right part in FIG. 10) bulges outward in the radial direction. It may be a non-circular shape that is substantially arc-shaped. Also in this case, the inner peripheral surface of the cylinder chamber (55) is formed in a non-circular shape based on the envelope of the outer peripheral surface of the piston (60).

    In the compression mechanism (50) according to the above embodiment, the outer peripheral surface of the piston (60) does not necessarily have to be non-circular, and may be a perfect circle. In this case, the compression mechanism (50) may be a circular oscillating piston type (swing type) in which a perfect circular piston (60) is connected to a blade (62) as a partitioning part to perform an oscillating motion. Good. In addition, the compression mechanism (50) has a rod-like or plate-like vane (partition part) whose tip is in sliding contact with the outer peripheral surface of the annular piston (60), and the piston (60) is located outside the crankshaft (32). A rotary vane type (rolling piston type) that performs an eccentric rotational motion while rotating may be used.

    As described above, the present invention relates to a compressor provided with a compression mechanism for compressing fluid, and is particularly useful for reducing pressure loss of fluid sucked into a cylinder chamber.

10 Compressor
11 Casing
12 Torso
15 Suction tube
20 Electric motor
50 Compression mechanism
51 cylinders
51a First cylinder (cylinder)
51b Second cylinder (cylinder)
60 pistons
60a 1st piston (piston)
60b 2nd piston (piston)
62 Blade (partition)
70 Cylinder body
70a Cylinder body
70b Cylinder body
72 Suction port
72a First suction port (suction port)
72b Second suction port (suction port)
73 Inflow port (bending port)
80 Connecting material
81 Connection port
81a First connection port (connection port)
81b Second connection port (connection port
83 Outflow port (bending port)

Claims (10)

A casing (11) having a cylindrical body (12);
An electric motor (20) fixed to the inner peripheral surface of the body (12) of the casing (11);
A piston (60, 60a, 60b) driven by the electric motor (20), and a cylinder (51, 51a, 51b) in which a cylinder chamber (55) for accommodating the piston (60, 60a, 60b) is formed; A compressor comprising a compression mechanism (50) having a partition (62) that partitions the cylinder (51, 51a, 51b) into a low pressure chamber (55a) and a high pressure chamber (55b),
The casing (11) includes a suction pipe (15) that passes through the casing (11) in the radial direction toward the central axis of the body (12) of the casing (11) and is fixed to the casing (11).
The cylinder (51, 51a, 51b) has an outflow end that communicates with the suction pipe (15) and opens into the cylinder chamber (55), and the partition portion (with respect to the axis of the suction pipe (15)). 62) A compressor characterized in that a suction port (72, 72a, 72b) having an axis inclined in the circumferential direction toward the opposite side of 62) is formed. In claim 1,
The cylinder (51, 51a, 51b) is formed with a connection port (81, 81a, 81b) through which the suction pipe (15) is inserted.
The suction port (72, 72a, 72b) communicates with the outflow end of the connection port (81, 81a, 81b), and the axis of the suction port (72, 72a, 72b) is connected to the connection port (81, 81a, 81b) a compressor characterized in that it is inclined in the circumferential direction toward the opposite side of the partition (62). In claim 2,
The cylinder (51,51a, 51b)
A cylinder body (70, 70a, 70b) in which the suction port (72, 72a, 72b) is formed;
A compressor having a connection member (80) attached to the cylinder body (70, 70a, 70b) and forming the connection port (81, 81a, 81b). In claim 3,
The connection member (80) has an inflow end connected to the connection port (81, 81a, 81b), an outflow end connected to the suction port (72, 72a, 72b), and the connection port (81, 81. A compressor characterized in that a bent port portion (83) bent so as to be coaxial with the suction port (72, 72a, 72b) with respect to the axial center of 81a, 81b) is formed. In claim 3,
The cylinder body (70, 70a, 70b) has an inflow end connected to the connection port (81, 81a, 81b) and an outflow end connected to the suction port (72, 72a, 72b). A compressor having a bent port portion (73) bent so as to be coaxial with the suction port (72, 72a, 72b) with respect to an axis of the port (81, 81a, 81b) . In any one of Claims 2 thru | or 5,
The connection port (81, 81a, 81b) is configured such that the inner diameter of the connection port (81, 81a, 81b) is larger than the inner diameter of the suction port (72, 72a, 72b). Compressor. In claim 6,
The length of the connection port (81, 81a, 81b) is L, the inner diameter of the connection port (81, 81a, 81b) is D, the inner diameter of the suction port (72, 72a, 72b) is d, and the connection port ( 81,81a, 81b) If the inclination angle of the axis of the suction port (72,72a, 72b) with respect to the axis is α,
The cylinder (51, 51a, 51b) is configured to satisfy a relational expression of D ≧ (d / cos α) + (L × tan α). In any one of Claims 1 thru | or 7,
The compressor characterized in that the inner peripheral shape of the suction port (72, 72a, 72b) is formed in an elliptical shape that is flat in the thickness direction of the cylinder (51, 51a, 51b). In any one of Claims 1, 2, 4-8,
The piston (60, 60a, 60b) has a non-circular outer peripheral surface and is configured to perform a swinging motion.
The cylinder (51, 51a, 51b) has a non-circular shape in which the inner peripheral surface of the cylinder chamber (55) is based on the envelope of the outer peripheral surface of the piston (60, 60a, 60b) that performs the swing motion. Composed of
The said partition part (62) is comprised with the braid | blade (62) connected with the outer peripheral surface of the said piston (60, 60a, 60b). The compressor characterized by the above-mentioned. In claim 3,
The piston (60, 60a, 60b) has a non-circular outer peripheral surface and is configured to perform a swinging motion.
The cylinder (51, 51a, 51b) has a non-circular shape in which the inner peripheral surface of the cylinder chamber (55) is based on the envelope of the outer peripheral surface of the piston (60, 60a, 60b) that performs the swing motion. Composed of
The partition part (62) is composed of a blade (62) connected to the outer peripheral surface of the piston (60, 60a, 60b),
The cylinder main body (70, 70a, 70b) has an axial length of the cylinder main body (70, 70a, 70b) which is the axial length of the cylinder main body (70, 70a, 70b) in the connecting member (80). Smaller than
The connection port (81, 81a, 81b) is configured such that the inner diameter of the connection port (81, 81a, 81b) is larger than the inner diameter of the suction port (72, 72a, 72b). Compressor.

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