JP7795685B2 - Scroll-type fluid machinery - Google Patents

Description

The present invention relates to a scroll-type fluid machine.

Patent Document 1 discloses a scroll compressor, which is a type of scroll-type fluid machine. This scroll compressor includes a fixed scroll, an orbiting scroll, and a drive shaft that rotates the orbiting scroll relative to the fixed scroll. The fixed scroll has an end plate, a spiral wrap erected on one surface of the end plate, and suction and discharge holes drilled in the end plate. The orbiting scroll has an end plate and a spiral wrap erected on one surface of the end plate so as to face the fixed scroll.

The suction hole of the fixed scroll is positioned in the range of the winding direction of the wrap of the orbiting scroll that is outermost of the wrap of the fixed scroll between the first confinement start position (more specifically, the position where the winding end of the wrap of the orbiting scroll contacts the wrap of the fixed scroll) and the second confinement start position (more specifically, the position where the winding end of the wrap of the fixed scroll contacts the wrap of the orbiting scroll).

Multiple first working chambers are formed between the inner circumferential side of the orbiting scroll wrap and the outer circumferential side of the fixed scroll wrap, and a first suction passage is formed on the outermost circumferential side of the orbiting scroll wrap. As the orbiting scroll wrap moves, the first working chambers move in the winding direction of the wrap and sequentially perform the suction process, compression process, and discharge process. During the suction process, the first working chamber draws in gas through the suction hole of the fixed scroll and the first suction passage. During the compression process, the first working chamber compresses the gas. During the discharge process, the first working chamber discharges compressed gas through the discharge hole of the fixed scroll.

Multiple second working chambers are formed between the inner circumferential side of the fixed scroll wrap and the outer circumferential side of the orbiting scroll wrap, and a second suction passage is formed on the outermost circumferential side of the orbiting scroll wrap. As the orbiting scroll wrap moves, the second working chambers move in the winding direction of the wrap and sequentially perform the suction process, compression process, and discharge process. During the suction process, the second working chamber draws in gas through the suction hole of the fixed scroll and the second suction passage. During the compression process, the second working chamber compresses the gas. During the discharge process, the second working chamber discharges compressed gas through the discharge hole of the fixed scroll.

As the orbiting scroll wrap moves, the cross-sectional area of the second suction passage increases, but the cross-sectional area of the first suction passage decreases. Therefore, in Patent Document 1, grooves are formed in the non-sliding area of the end plate of the fixed scroll to expand the cross-sectional area of the first suction passage. This reduces suction loss.

Japanese Patent Application Laid-Open No. 2008-185020

In Patent Document 1, grooves are formed in the non-sliding area of the end plate of the fixed scroll to increase the cross-sectional area of the first suction passage, thereby attempting to reduce suction loss, but there are limits to how much reduction can be achieved.

The present invention was made in consideration of the above, and one of its objectives is to reduce suction losses.

The present invention includes a plurality of means for solving the above-mentioned problems, and one example thereof is a scroll-type fluid machine including a fixed scroll having an end plate, a spiral wrap erected on one surface of the end plate, and an inlet hole drilled in the end plate, an orbiting scroll having an end plate and a spiral wrap erected on one surface of the end plate so as to face the fixed scroll, and a drive shaft for orbiting the orbiting scroll relative to the fixed scroll, wherein the inlet hole of the fixed scroll has a first confinement start position where a winding end end of the wrap of the orbiting scroll contacts the wrap of the fixed scroll and a second confinement start position where a winding end end of the wrap of the fixed scroll contacts the wrap of the orbiting scroll. Between the start position and the start position, the wrap of the orbiting scroll is positioned within a range in the winding direction of the wrap that is outermost relative to the wrap of the fixed scroll, and is intermittently in direct communication with a working chamber formed between the inner side of the wrap of the orbiting scroll and the outer side of the wrap of the fixed scroll, and the suction hole of the fixed scroll has an opening that opens to one surface of the end plate of the fixed scroll, and when the crank angle of the drive shaft is in a first range, the entire opening is in communication with the working chamber via an suction passage, and when the crank angle of the drive shaft is in a second range, a part of the opening is in direct communication with the working chamber and the other part of the opening is in communication with the working chamber via the suction passage.

According to the present invention, suction losses can be reduced.

Further issues, configurations, and effects other than those mentioned above will become clear from the explanation below.

1 is a side view illustrating a structure of a scroll compressor according to an embodiment of the present invention. 1 is an axial cross-sectional view illustrating the structure of a scroll compressor according to an embodiment of the present invention. 3 is a radial cross-sectional view taken along the line III-III in FIG. 2, showing the case where the crank angle of the drive shaft is 0 degrees. 3 is a radial cross-sectional view taken along the line III-III in FIG. 2, showing the case where the crank angle of the drive shaft is 90 degrees. 3 is a radial cross-sectional view taken along the line III-III in FIG. 2, showing the case where the crank angle of the drive shaft is 180 degrees. 3 is a radial cross-sectional view taken along the line III-III in FIG. 2, showing the case where the crank angle of the drive shaft is 270 degrees. FIG. 3D is a partially enlarged cross-sectional view of a portion IV of FIG. FIG. 5 corresponds to FIG. 4 and is a diagram for explaining the positional relationship between the suction hole of the fixed scroll and the tip seal of the orbiting scroll. FIG. 10 is a partially enlarged cross-sectional view of a first modified example to which the present invention is applied. FIG. 10 is a partially enlarged cross-sectional view of a second modified example to which the present invention is applied.

One embodiment of the present invention will be described using Figures 1 to 5.

Figure 1 is a side view showing the structure of a scroll compressor in this embodiment. Figure 2 is an axial cross-sectional view showing the structure of a scroll compressor in this embodiment. Figures 3A to 3D are radial cross-sectional views taken along arrows III-III in Figure 2, showing the cases where the crank angle of the drive shaft is 0 degrees, 90 degrees, 180 degrees, and 270 degrees, respectively. Figure 4 is a partially enlarged cross-sectional view of portion IV in Figure 3D. Figure 5 corresponds to Figure 4 and is a diagram for explaining the relationship between the suction hole of the fixed scroll and the tip seal of the orbiting scroll.

The scroll compressor of this embodiment comprises a casing 10, a fixed scroll 11, an orbiting scroll 12, a drive shaft 13, a cooling fan 14, and a duct 15. The fixed scroll 11 is connected to the open side of the casing 10 (the right side in Figures 1 and 2). The orbiting scroll 12 is housed within the casing 10. The drive shaft 13 is rotatably supported by a bearing 16 within the casing 10. The cooling fan 14 rotates together with the drive shaft 13 to generate cooling air. The duct 15, only a portion of which is shown, guides the cooling air generated by the cooling fan 14.

The fixed scroll 11 has a substantially circular end plate 17, a spiral wrap 18 erected on one surface of the end plate 17 (the left surface in Figure 2), an intake hole 19 drilled in the end plate 17 and extending in a direction perpendicular to the surface of the end plate 17 (left-right direction in Figure 2), and a discharge hole 20 drilled in the end plate 17 and extending in a direction perpendicular to the surface of the end plate 17. An intake filter 21 is connected to the intake hole 19 of the fixed scroll 11, and a discharge pipe 22 is connected to the discharge hole 20 of the fixed scroll 11.

The fixed scroll 11 further has multiple cooling fins 23 erected on the opposite surface of the end plate 17 (the surface on the right side in Figure 2) and a cover 24 attached to the tip side of the cooling fins 23. Cooling air from the duct 15 flows through the flow path formed by the cooling fins 23 and the cover 24. This cools the fixed scroll 11.

The orbiting scroll 12 has a substantially circular end plate 25, a spiral wrap 26 erected on one surface of the end plate 25 (the right surface in Figure 2) facing the fixed scroll 11, a plurality of cooling fins 27 erected on the opposite surface of the end plate 25 (the left surface in Figure 2), and a plate 28 attached to the tip side of the cooling fins 27. Cooling air from the duct 15 flows through the flow path formed by the cooling fins 27 and the plate 28. This cools the orbiting scroll 12.

The wrap 26 of the orbiting scroll 12 and the wrap 18 of the fixed scroll 11 are arranged symmetrically. A groove 29 (see Figure 5) is formed on the tip side of the wrap 26 of the orbiting scroll 12, and a tip seal (sliding member) 30 (see Figure 5) is inserted into the groove 29, with the tip seal 30 coming into contact with the end plate 17 of the fixed scroll 11. Similarly, a groove is formed on the tip side of the wrap 18 of the fixed scroll 11, and a tip seal is inserted into this groove, with the tip seal coming into contact with the end plate 25 of the orbiting scroll 12. This improves the sealing of the working chamber, which will be described later.

A crank portion 31 is provided on one end of the drive shaft 13 (the right side in Figures 1 and 2). The center O2 of the crank portion 31 of the drive shaft 13 is eccentric from the center O1 of the drive shaft 13 and is connected to the boss portion of the plate 28 of the orbiting scroll 12 via an orbiting bearing 32.

The other end of the drive shaft 13 (left side in Figures 1 and 2) protrudes outside the casing 10 and is provided with a pulley 33. A belt (not shown) is stretched between the pulley (not shown) and the pulley 33, which is provided on the rotating shaft (not shown) of the electric motor. This transmits the rotational force of the electric motor, causing the drive shaft 13 to rotate and the orbiting scroll 12 to orbit relative to the fixed scroll 11. A rotation prevention mechanism is provided within the casing 10 to prevent the orbiting scroll 12 from rotating on its own axis.

The crank angle of the drive shaft 13 is the rotation angle of the straight line connecting the aforementioned centers O1 and O2, and as shown in Figure 3A, the angle at which the winding end of the wrap 26 of the orbiting scroll 12 contacts the wrap 18 of the fixed scroll 11 and the winding end of the wrap 18 of the fixed scroll 11 contacts the wrap 26 of the orbiting scroll 12 is taken as the reference angle (0 degrees).

The suction hole 19 of the fixed scroll 11 is located between the first confinement start position A (specifically, the position where the winding end of the wrap 26 of the orbiting scroll 12 contacts the wrap 18 of the fixed scroll 11) and the second confinement start position B (specifically, the position where the winding end of the wrap 18 of the fixed scroll 11 contacts the wrap 26 of the orbiting scroll 12) shown in FIG. 3A, in the range of the winding direction of the wrap 18 (in other words, the range of the circumferential direction of the drive shaft 13) where the wrap 26 of the orbiting scroll 12 is located outermost from the wrap 18 of the fixed scroll 11. In this embodiment, the suction hole 19 of the fixed scroll 11 is located at a position in the winding direction of the wrap 18 (in other words, a position in the circumferential direction of the drive shaft 13) that is midway between the first confinement start position A and the second confinement start position B.

A plurality of first working chambers 34 are formed between the inner side of the wrap 26 of the orbiting scroll 12 (more specifically, the inner surface CD shown in Figure 3B) and the outer side of the wrap 18 of the fixed scroll 11 (more specifically, the outer surface FG shown in Figure 3B), and a first suction flow path 35 is formed on the outermost side of the wrap 26 of the orbiting scroll 12.

As the wrap 26 of the orbiting scroll 12 moves, the first working chamber 34 moves in the winding direction of the wrap 26, sequentially performing the suction process, compression process, and discharge process. More specifically, for example, when the crank angle of the drive shaft 13 is between 0 and 360 degrees (in other words, during one rotation of the drive shaft 13), the suction process is performed, in which gas (e.g., air) is drawn in through the suction filter 21, the suction hole 19 of the fixed scroll 11, and the first suction passage 35. When the crank angle of the drive shaft 13 is between 360 and 1170 degrees (in other words, by the time the drive shaft 13 has rotated three times and the crank angle of the drive shaft 13 reaches 90 degrees), the compression process is performed, in which gas is compressed (pressurized). When the crank angle of the drive shaft 13 is 1170 degrees or greater, the discharge process is performed, in which compressed gas is discharged through the discharge hole 20 of the fixed scroll 11 and the discharge pipe 22.

A plurality of second working chambers 36 are formed between the inner side of the wrap 18 of the fixed scroll 11 (more specifically, the inner surface HG shown in Figure 3B) and the outer side of the wrap 26 of the orbiting scroll 12 (more specifically, the outer surface ED shown in Figure 3B), and a second suction flow path 37 is formed on the outermost side of the wrap 26 of the orbiting scroll 12.

As the wrap 26 of the orbiting scroll 12 moves, the second working chamber 36 moves in the winding direction of the wrap 26, sequentially performing the suction process, compression process, and discharge process. More specifically, for example, when the crank angle of the drive shaft 13 is between 0 and 360 degrees (in other words, during one rotation of the drive shaft 13), the suction process is performed, in which gas is drawn in through the suction filter 21, the suction hole 19 of the fixed scroll 11, and the second suction passage 37. When the crank angle of the drive shaft 13 is between 360 and 1170 degrees (in other words, by the time the drive shaft 13 has rotated three times and the crank angle of the drive shaft 13 reaches 90 degrees), the compression process is performed, in which gas is compressed. When the crank angle of the drive shaft 13 is 1170 degrees or greater, the discharge process is performed, in which compressed gas is discharged through the discharge hole 20 of the fixed scroll 11 and the discharge pipe 22.

As the wrap 26 of the orbiting scroll 12 moves, the cross-sectional area of the second suction passage 37 increases, while the cross-sectional area of the first suction passage 35 decreases. Therefore, a feature of this embodiment is that the suction hole 19 of the fixed scroll 11 intermittently communicates directly with the first working chamber 34 during the suction process. More specifically, the suction hole 19 of the fixed scroll 11 has an opening 19a that opens to one surface of the end plate 17, and the opening 19a partially overlaps with the range of movement of the wrap 26 of the orbiting scroll 12. In other words, the opening 19a of the suction hole 19 of the fixed scroll 11 partially overlaps with the range of movement of the first working chamber 34 during the suction process.

When the crank angle of the drive shaft 13 is within a first range (e.g., 0 to 225 degrees and 315 to 360 degrees), the opening 19a of the suction hole 19 of the fixed scroll 11 does not overlap with the first working chamber 34 during the suction process. Therefore, the suction hole 19 of the fixed scroll 11 communicates with the first working chamber 34 during the suction process through the entire opening 19a via the first suction flow path 35.

On the other hand, for example, when the crank angle of the drive shaft 13 is in the second range (e.g., 225 to 315 degrees), a portion of the opening 19a of the suction hole 19 of the fixed scroll 11 (the radially inner portion of the drive shaft 13) overlaps with the first working chamber 34 during the suction process, while the other portion (the radially outer portion of the drive shaft 13) does not overlap with the first working chamber 34 during the suction process. Therefore, the suction hole 19 of the fixed scroll 11 is directly connected to the first working chamber 34 during the suction process through a portion of the opening 19a, and is connected to the first working chamber 34 during the suction process through the other portion of the opening 19a via the first suction flow path 35. This reduces suction loss compared to when the suction hole 19 of the fixed scroll 11 does not directly communicate with the first working chamber 34 during the suction process.

In addition, in this embodiment, the suction hole 19 of the fixed scroll 11 does not overlap with the end of the tip seal 30 inserted into the groove 29 of the wrap 26 of the orbiting scroll 12 at the end of the winding (the outer end in the winding direction), but instead overlaps intermittently with other parts of the tip seal 30 (see Figure 5). Therefore, unlike when the suction hole 19 of the fixed scroll 11 overlaps with the end of the tip seal 30, it is possible to prevent the tip seal 30 from falling off from the groove 29 of the wrap 26.

In the above embodiment, the opening 19a of the suction hole 19 of the fixed scroll 11 is described as being trapezoidal in shape, but this is not limited to this. For example, as in the first modified example shown in Figure 6, the opening 19a of the suction hole 19 of the fixed scroll 11 may be comb-shaped, branching in the winding direction of the wrap. In this modified example, the area where the tip seal 30 inserted into the groove 29 of the wrap 26 of the orbiting scroll 12 overlaps with the opening 19a is reduced, further preventing the tip seal 30 from falling off from the groove 29 of the wrap 26.

In addition, in the above embodiment, the suction hole 19 of the fixed scroll 11 has one opening 19a that opens to one surface of the end plate 17, but this is not limited to this. For example, as in the second modified example shown in Figure 7, the suction hole 19 of the fixed scroll 11 may have multiple openings 19b, 19c that open to one surface of the end plate 17 and are separated from each other.

In this modified example, when the crank angle of the drive shaft 13 is within a first range (e.g., 0 to 225 degrees and 315 to 360 degrees), the openings 19b and 19c of the suction hole 19 of the fixed scroll 11 do not overlap with the first working chamber 34 during the suction process. Therefore, the suction hole 19 of the fixed scroll 11 communicates with the first working chamber 34 during the suction process from the openings 19b and 19c via the first suction flow path 35.

On the other hand, for example, when the crank angle of the drive shaft 13 is in the second range (e.g., 225 to 315 degrees), opening 19b of the suction hole 19 of the fixed scroll 11 overlaps with the first working chamber 34 during the suction process, while opening 19c does not overlap with the first working chamber 34 during the suction process. Therefore, the suction hole 19 of the fixed scroll 11 is directly connected to the first working chamber 34 during the suction process through opening 19b, and is also connected to the first working chamber 34 during the suction process through opening 19c via the first suction flow path 35. This reduces suction loss compared to when the suction hole 19 of the fixed scroll 11 does not directly communicate with the first working chamber 34 during the suction process.

In addition, in this modified example, the area where the chip seal 30 inserted into the groove 29 of the wrap 26 of the orbiting scroll 12 overlaps with the openings 19b and 19c is reduced, further preventing the chip seal 30 from falling off from the groove 29 of the wrap 26.

Note that while the above description has been given using an example of the present invention being applied to a scroll compressor, which is one type of scroll fluid machine, this is not limited to this. The present invention may also be applied to other scroll fluid machines (specifically, scroll vacuum pumps, scroll expanders, etc.).

11... Fixed scroll, 12... Orbiting scroll, 13... Drive shaft, 17... End plate, 18... Wrap, 19... Suction hole, 19a, 19b, 19c... Openings, 25... End plate, 26... Wrap, 29... Groove, 30... Tip seal, 34... First working chamber, 35... First suction flow passage

Claims (4)

a fixed scroll having an end plate, a spiral wrap standing on one surface of the end plate, and an intake hole drilled in the end plate;
an end plate; and an orbiting scroll having a spiral wrap erected on one surface of the end plate so as to face the fixed scroll;
a drive shaft for rotating the orbiting scroll relative to the fixed scroll,
the suction hole of the fixed scroll is disposed in a range in the winding direction of the wrap of the orbiting scroll that is on the outermost side of the wrap of the fixed scroll, between a first confinement start position where the winding end of the wrap of the orbiting scroll contacts the wrap of the fixed scroll and a second confinement start position where the winding end of the wrap of the fixed scroll contacts the wrap of the orbiting scroll, and is in direct intermittent communication with a working chamber formed between the inner peripheral side of the wrap of the orbiting scroll and the outer peripheral side of the wrap of the fixed scroll ,
The suction hole of the fixed scroll has an opening that opens to one surface of the end plate of the fixed scroll, and when the crank angle of the drive shaft is in a first range, the entire opening is connected to the working chamber via a suction passage, and when the crank angle of the drive shaft is in a second range, a part of the opening is connected directly to the working chamber and another part of the opening is connected to the working chamber via the suction passage . The scroll type fluid machine according to claim 1 ,
The scroll-type fluid machine, wherein the opening has a comb shape that branches in the winding direction of the wrap. a fixed scroll having an end plate, a spiral wrap standing on one surface of the end plate, and an intake hole drilled in the end plate;
an end plate; and an orbiting scroll having a spiral wrap erected on one surface of the end plate so as to face the fixed scroll;
a drive shaft for rotating the orbiting scroll relative to the fixed scroll,
the suction hole of the fixed scroll is disposed in a range in the winding direction of the wrap of the orbiting scroll that is on the outermost side of the wrap of the fixed scroll, between a first confinement start position where the winding end of the wrap of the orbiting scroll contacts the wrap of the fixed scroll and a second confinement start position where the winding end of the wrap of the fixed scroll contacts the wrap of the orbiting scroll, and is in direct intermittent communication with a working chamber formed between the inner peripheral side of the wrap of the orbiting scroll and the outer peripheral side of the wrap of the fixed scroll,
The suction hole of the fixed scroll has a first opening and a second opening that open to one surface of the end plate of the fixed scroll and are separated from each other, and when the crank angle of the drive shaft is in a first range, the first opening and the second opening communicate with the working chamber via a suction passage, and when the crank angle of the drive shaft is in a second range, the first opening communicates directly with the working chamber and the second opening communicates with the working chamber via the suction passage. a fixed scroll having an end plate, a spiral wrap standing on one surface of the end plate, and an intake hole drilled in the end plate;
an end plate; and an orbiting scroll having a spiral wrap erected on one surface of the end plate so as to face the fixed scroll;
a drive shaft for rotating the orbiting scroll relative to the fixed scroll,
the suction hole of the fixed scroll is disposed in a range in the winding direction of the wrap of the orbiting scroll that is on the outermost side of the wrap of the fixed scroll, between a first confinement start position where the winding end of the wrap of the orbiting scroll contacts the wrap of the fixed scroll and a second confinement start position where the winding end of the wrap of the fixed scroll contacts the wrap of the orbiting scroll, and is in direct intermittent communication with a working chamber formed between the inner peripheral side of the wrap of the orbiting scroll and the outer peripheral side of the wrap of the fixed scroll,
The orbiting scroll further includes a sliding member inserted into a groove formed on a tip side of the wrap,
A scroll-type fluid machine, characterized in that the suction hole of the fixed scroll does not overlap with an end of the sliding member, but intermittently overlaps with other portions of the sliding member.