Fig. 1 is a vertical cross-sectional view of a compressor of embodiment 1 according to the present invention, Fig. 2 is a top cross-sectional view of the compressor of the same embodiment, and Fig. 3 is an exploded perspective view of a component attached to an open end portion of a cylinder in the same embodiment.
Further, Fig. 4 is an elevational view of a suction muffler in the same embodiment, Fig. 5 is a vertical cross-sectional view of the suction muffler in the same embodiment, Fig. 6 is a cross-sectional view taken along line 6A-6A of Fig. 4, Fig. 7 is an elevational view of a valve plate viewed from a side of the suction muffler in the same embodiment, Fig. 8 is an elevational view of the valve plate viewed from a side of the cylinder in the same embodiment, and Fig. 9 is a cross-sectional view taken along line 9A-9A of Fig. 7.
As shown in Fig. 1 and Fig. 2, hermetic container 101 contains lubricant oil 102 and compression element 105 driven by electrical motor 104 therein.
Compression element 105 is provided with cylinder 107 that defines compression chamber 106, piston 108, shaft 109, con rod 110, valve plate 112 that seals an end of cylinder 107 and is provided with suction hole 111, suction lead 114 that opens and closes suction hole 111, suction muffler 116, and cylinder head 118 that defines a discharge space (not shown).
Piston 108 is reciprocatingly slidably housed within cylinder 107, and connected to shaft 109 by con rod 110.
A lower tip end of shaft 109 is soaked in lubricant oil 102, and an oil feeding mechanism (not shown) for feeding lubricant oil 102 to each sliding portion of compression element 105 is provided.
Next, a structure of suction muffler 116 is described with reference to Fig. 1 through Fig. 6.
Suction muffler 116 is made of a resin such as PBT, and is provided with suction hole 119, muffling space 120, and communicating tube 122. Communicating tube 122 includes communicating tube outlet 124 that is communicated with suction hole 111, and is positioned so as to extend along center axis 140 that lies vertically with respect to center axis 126 of suction hole 111.
Communicating tube outlet 124 is provided with protrusion 128 that protrudes toward a direction in which the refrigerant gas flows (direction along center axis 140) with respect to a projection of suction hole 111, in a direction of center axis 126 of suction hole 111.
Next, valve plate 112 will be described with reference to Fig. 7 through Fig. 9.
Valve plate 112 is made of material such as sintered metal, for example, and includes inhalation pathway 132 that is directed toward suction hole 111 from an end of communicating tube outlet 124 of valve plate 112. Inhalation pathway 132 is provided for valve plate 112 at a position facing toward protrusion 128 of suction muffler 116.
Further, inhalation pathway 132 is defined by inclination 143 and curvature 130 as a circular arc whose radius is about 2 mm.
Further, suction hole 111 in a planar shape is noncircular, and communicating tube outlet 124 of suction muffler 116 has substantially the same shape as suction hole 111, other than protrusion 128, in the projection along axial core 126 of suction hole 111. Specifically, suction hole 111 in the planar shape here defines an opening that is noncircular and enclosed by a plurality of circular arcs. Further, as shown from Fig. 7 through Fig. 9, the noncircular shape of the opening of suction hole 111 in valve plate 112 has a predetermined length and is substantially the same shape along the direction of axial core 126.
Further, a long side of suction hole 111 in the planar shape is about 14 mm, which is longer than 8 mm, an opening length vertical to a direction in which communicating tube 122 of suction muffler 116 extends. Accordingly, the opening length becomes longer when the refrigerant gas is suctioned from communicating tube outlet 124 to suction hole 111 through communicating tube 122.
Further, protrusion 128 of suction muffler 116 protrudes toward the direction in which the refrigerant gas flows, defines a circular arc whose radius is about 4 mm in the projection along center axis 126 of suction hole 111.
Further, cross-section 141 of an opening portion of protrusion 128 in a plane vertical to the direction in which communicating tube 122 of suction muffler 116 extends is substantially quadrangular with about 8 mm square, which is almost the same as cross-section 142 of communicating tube 122.
Further, second inhalation pathway 136 defined by second curvature 134, which is a circular arc whose radius is about 2 mm, is provided on an opposite side of protrusion 128 with respect to suction hole 111.
An operation and behavior of the compressor configured as described above will be described with reference to Fig. 1 through Fig. 9.
Shaft 109 is driven rotary when power is supplied to electrical motor 104. Then, the rotary motion of shaft 109 moves piston 108 reciprocatingly via con rod 110, and the refrigerant gas is suctioned and compressed in compression chamber 106.
At this time, the refrigerant gas from a refrigerating circuit (not shown) is first released in hermetic container 101, and then suctioned into suction muffler 116 through suction hole 119.
The refrigerant gas suctioned into suction muffler 116 is then, after released into muffling space 120, suctioned into cylinder 107 through communicating tube 122 and suction hole 111. The refrigerant gas suctioned into cylinder 107 is compressed by piston 108, and discharged back into the external cooling circuit (not shown) via the discharge space (not shown) of cylinder head 118.
Here, communicating tube outlet 124 that is communicated with suction hole 111 is provided with protrusion 128, and inhalation pathway 132 that directs the refrigerant gas to suction hole 111 is provided for valve plate 112 that faces toward protrusion 128. By this, the refrigerant gas that first flows into protrusion 128 and is then directed to suction hole 111 without directly flowing into suction hole 111 is prevented from being diffused by protrusion 128. In this manner, the refrigerant gas is directed smoothly into suction hole 111, thereby reducing a suction resistance of the flow of the refrigerant gas.
In addition, inhalation pathway 132 is provided with curvature 130 that is directed toward suction hole 111 from an end face of valve plate 112 on a side of communicating tube outlet 124. By this, the refrigerant gas flows smoothly preventing separation of the flow, and flows smoothly through inhalation pathway 132 along curvature 130 toward suction hole 111. Therefore, as it is possible to reduce the suction resistance of the flow of the refrigerant gas, a suction mass of the refrigerant per unit time (refrigerant circulation volume) increases and consequently the workload per unit time increases. Thus, a compressor with high efficiency can be realized.
Further, making the shape of suction hole 111 noncircular can reduce a circumferential stress as a tensile stress produced, during compression operation, at a portion of suction lead 114 that is in contact with suction hole 111. With this, it is possible to reduce damages such as a crack in suction lead 114, and a compressor with high reliability can be realized.
Further, by making the shape of communicating tube outlet 124 substantially the same as the shape of suction hole 111, there is no suction resistance that inhibits the flow of the refrigerant gas from communicating tube outlet 124 to suction hole 111 other than protrusion 128, and the flow of the refrigerant gas does not stagnate. With this, in addition to the effects of the increases in the refrigerant circulation volume and workload per unit time, a high efficiency compressor with a smooth refrigerant gas flow from communicating tube 122 to suction hole 111 can be realized.
Further, making the opening length of suction hole 111 longer than the opening length vertical to the direction in which communicating tube 122 of suction muffler 116 extends increases a space through which the refrigerant gas flows from communicating tube 122 to suction hole 111 smoothly. With this, the flow resistance of the refrigerant gas that is suctioned can be still reduced.
Further, protrusion 128 of suction muffler 116 protrudes toward the direction in which the refrigerant gas flows, defining the circular arc in the projection along center axis 126 of suction hole 111. With this, it is possible to prevent a secondary flow from being produced at protrusion 128 where the refrigerant gas flows quickly, and the flow of the refrigerant gas flows increasingly toward suction hole 111 without being inhibited.
In addition, cross-section 141 of an opening portion of protrusion 128 along a plane vertical to the direction in which communicating tube 122 of suction muffler 116 extends is substantially the same as cross-section 142 of communicating tube 122. With this, a flow resistance that inhibits the flow of the refrigerant gas to protrusion 128 is not present from communicating tube 122 to communicating tube outlet 124, and the flow does not stagnant. Therefore, production of the secondary flow of the refrigerant gas can be reduced, and the refrigerant gas flows smoothly toward communicating tube outlet 124.
Further, valve plate 112 is provided with second inhalation pathway 136 defined by second curvature 134 and second inclination 145, on an opposite side of inhalation pathway 132 with respect to suction hole 111. With this, the flow of the refrigerant gas from communicating tube outlet 124 to suction hole 111 smoothly moves, suppressing the separation at second inhalation pathway 136. Therefore, the flow resistance of the refrigerant gas can be reduced, and the refrigerant gas toward suction hole 111 flows more smoothly, thereby a compressor with higher efficiency can be realized.
In the above description, the case in which second inhalation pathway 136 is defined by second curvature 134 and second inclination 145 is explained. However, second inhalation pathway 136 can be defined by only one of second curvature 134 and second inclination 145.
Specifically, the compressor according to the present invention includes a hermetic container that contains lubricant oil therein; an electrical motor; and a compression element that is driven by the electrical motor and compresses refrigerant gas, the electrical motor and the compression element being housed within the hermetic container. The compression element includes a cylinder that defines a compression chamber; a valve plate that seals an end of the cylinder and is provided with a suction hole; a suction lead that opens and closes the suction hole; a suction muffler that defines a muffling space and is provided with a communicating tube; and a cylinder head. Further, the communicating tube is provided with a communicating tube outlet that is communicated with the suction hole, and being disposed so as to extend in a vertical direction to the center axis of the suction hole.
The compressor according to the present invention may be configured such that the communicating tube outlet is provided with a protrusion that protrudes toward a direction in which the refrigerant gas flows rather than a direction of the suction hole in a projection along a direction of the axial core of the suction hole, and the valve plate facing toward the protrusion is provided with a inhalation pathway that directs the refrigerant gas to the suction hole, thereby reducing a flow resistance of the refrigerant gas.
With such a configuration, it is possible to prevent the flow of the refrigerant gas from being diffused at the protrusion at which the refrigerant gas flows quickly and changes its direction. Further, as the refrigerant gas is allowed to flow smoothly from the protrusion to the suction hole, it is possible to reduce the loss related to the flow of the suctioned refrigerant gas. With this, the suction mass of the refrigerant per unit time (refrigerant circulation volume) increases and consequently the workload per unit time increases. Thus, a compressor with high efficiency can be realized.
Further, the inhalation pathway can be defined by one of an inclination and a curvature that is directed toward the suction hole from an end of the valve plate on a side of the communicating tube outlet.
With such a configuration, in addition to the advantages of suppressing the separation of the flow in the inhalation pathway, the increased refrigerant circulation volume, and the increased workload per unit time, it is further possible to reduce the flow resistance of the refrigerant gas from the communicating tube outlet to the suction hole. With this, the refrigerant gas flows more smoothly toward the suction hole, thereby a compressor with higher efficiency can be realized.
Further, the shape of the suction hole may be noncircular, and the shape of the communicating tube outlet may be substantially the same as the shape of the suction hole, other than the protrusion in the projection along the direction of the center axis of the suction hole.
As described above, making the shape of the suction hole noncircular can reduce the circumferential stress as the tensile stress produced, during compression operation, at the portion of the suction lead that is in contact with the suction hole. Accordingly, in addition to the advantages of the increased refrigerant circulation volume and the increased workload per unit time, it is further possible to reduce damages such as a crack in the suction lead, and a compressor with high reliability can be realized.
Further, by making the shape of the communicating tube outlet substantially the same as the suction hole, there is no flow resistance that inhibits the flow of the refrigerant gas from the communicating tube outlet to the suction hole other than the protrusion, and the flow of the refrigerant gas does not stagnant.
With this, in addition to the advantages of the increased refrigerant circulation volume and the increased workload per unit time, it is further possible to allow the refrigerant gas to flow more smoothly from the communicating tube to the suction hole, and a compressor with high efficiency can be realized.
Further, an opening length of the suction hole may be longer than an opening length vertical to the direction along which the communicating tube extends.
With such a configuration, the space through which the refrigerant gas flows from the communicating tube to the suction hole smoothly increases. With this, in addition to the above-described advantages, it is further possible to reduce the flow resistance of the refrigerant gas that is further suctioned, and a compressor with high efficiency can be realized.
Further, the shape of the protrusion may be circular. With such a configuration, it is possible to reduce the production of the secondary flow such as the diffusion of the flow of the refrigerant gas at the protrusion at which the refrigerant gas flows quickly and changes its direction. With this, in addition to the above-described advantages, it is further possible to allow the refrigerant directed to the suction hole to flow more smoothly and to reduce the flow resistance of the suctioned refrigerant gas, thereby a compressor with high efficiency can be realized.
Further, a cross-sectional shape of the opening portion of the protrusion along a plane vertical to the direction along which the communicating tube extends may be substantially the same as the cross-sectional shape of the communicating tube.
With such a configuration, a cross-sectional area of the refrigerant gas flow does not vary from the communicating tube to the protrusion of the communicating tube, and accordingly, the flow resistance of the refrigerant gas does not increase. With this, in addition to the above-described advantages, it is possible to prevent the flow of the refrigerant gas toward the communicating tube outlet from being diffused, and a compressor with higher efficiency can be realized.
Further, the compressor according to the present invention may be configured such that the valve plate is provided, at a portion opposite to the protrusion with respect to the suction hole, with a second inhalation pathway directing the refrigerant gas to the suction hole, and the second inhalation pathway is defined by one of a second inclination and a second curvature that is directed toward the suction hole from an end of the valve plate on a side of the communicating tube outlet.
With such a configuration, the refrigerant gas flows smoothly from the communicating tube outlet to the suction hole through the second inhalation pathway, preventing the flow of the refrigerant gas from being separated. With this, in addition to the above-described advantages, it is possible to further reduce the flow resistance of the refrigerant gas, and to allow the refrigerant gas to flow more smoothly toward the suction hole, thereby a compressor with higher efficiency can be realized.