WO2007013406A1

WO2007013406A1 - Piston type compressor

Info

Publication number: WO2007013406A1
Application number: PCT/JP2006/314587
Authority: WO
Inventors: Akinobu Kanai; Masaki Ota; Akihito Yamanouchi; Osamu Nakayama; Yoshio Taneda; Masaya Sakamoto
Original assignee: Kabushiki Kaisha Toyota Jidoshokki
Priority date: 2005-07-25
Filing date: 2006-07-24
Publication date: 2007-02-01
Also published as: US20080193304A1

Abstract

A piston type compressor wherein each of the intake ports (43) of a cylinder block (11) comprises a narrow passage (50) on the top dead center side and a wide passage (51) on the bottom dead center side. The intake communication passage (45) of a rotary valve (41) is passed through the first trailing edge (50b) of the narrow passage (50) before passed through the second trailing edge (51b) of the wide passage (51). The high-pressure groove (47) of a residual gas bypass groove (46) faces only the narrow passage (50) of the intake port (43A) when it communicates with the intake port (43A) corresponding to a high-pressure side compression chamber (26). The width (Tc) of the rotary valve (41) between the first trailing edge (50b) and the second leading edge (51a) of the wide passage (51) in the rotating direction is smaller than the seal width (W) of a seal area (S) portion between the high-pressure groove (47) and the outlet (45b) of the intake communication passage (45). As a result, a compression efficiency can be increased by suppressing the intake loss amount of gases into the compression chamber while advancing the intake start timing of the gases into the compression chamber.

Description

Specification

Piston compressor

Technical field

[0001] The present invention relates to a piston compressor using a rotary valve. More specifically, the present invention relates to a piston-type compressor having a configuration in which the gas remaining in the high-pressure side compression chamber after completion of discharge is bypassed to the low-pressure side compression chamber.

Background art

In the piston compressor disclosed in Patent Document 1, the piston is reciprocated by each cylinder bore as the rotating shaft rotates. As a result, the gas is sucked into the compression chamber from the suction pressure region through the rotary valve, the gas is compressed in the compression chamber, and the gas is discharged from the compression chamber. The suction communication path of the rotary valve that rotates synchronously with the rotary shaft sequentially connects the conduction path extending from each compression chamber to the suction pressure region in the suction stroke. The suction communication passage extends in an elongated shape along the axial direction of the rotary valve and has a constant width.

[0003] Further, the outer peripheral surface of the rotary valve has a residual gas bypass groove that communicates the conduction path corresponding to the high-pressure side compression chamber after completion of the discharge with the conduction path corresponding to the low-pressure side compression chamber. The gas that remains without being discharged in the compression chamber after completion of discharge, that is, residual gas, is bypassed or recovered to the compression chamber on the low-pressure side through the high-pressure side conduction path, the residual gas bypass groove, and the low-pressure side conduction path. Therefore, gas re-expansion during the suction stroke of the compression chamber is reduced. As a result, the gas in the suction pressure region can be reliably sucked into the compression chamber, and the volumetric efficiency of the piston compressor can be improved.

[0004] In the piston type compressor, it is necessary to prevent a gas path from the high-pressure opening of the residual gas bypass groove to the suction communication passage of the rotary valve through the conduction path of the cylinder block. For this reason, the outer peripheral surface of the rotary valve facing the conduction path of the cylinder block has a seal region. The seal region closes the conduction path of the cylinder block between the high-pressure opening of the residual gas bypass groove and the suction communication passage of the single valve.

11 and 12 are exploded views in which the outer peripheral surface 100a of the rotary valve 100 is developed in a planar shape. The cylinder block conduction path 101 is connected to the outer peripheral surface 100a of the rotary valve 100. It corresponds. As shown in FIG. 11, a seal region S is provided on the outer peripheral surface 100a of the rotary valve 100. The seal region S requires an area between the high-pressure opening 103a of the residual gas bypass groove 103 and the opening 102a of the rotary valve suction communication path 102 so that the opening 101a of the cylinder block conduction path 101 can be closed.

However, as the area of the seal region S increases, the seal width W between the high-pressure opening 103a and the suction communication path 102 along the rotation direction of the rotary valve 100 increases. In other words, the high-pressure opening 103 a moves away from the opening 102 a of the suction communication path 102. Then, the time from the timing when the opening 101a of the cylinder block conduction path 101 starts to communicate with the high-pressure opening 103a to the timing when the opening 101a of the conduction path 101 starts to communicate with the opening 102a of the suction communication path 102 of the rotary valve. Increase. This increase in time difference means that the time from when the gas in the compression chamber on the high pressure side is recovered until the gas is sucked into the compression chamber is increased. As a result, the gas suction start timing into the compression chamber is delayed. As a result, the amount of gas sucked into the compression chamber decreases and the compression efficiency decreases.

Accordingly, as shown in FIG. 12, it is conceivable to reduce the area of the seal region S, that is, to reduce the seal width W. Accordingly, from the timing when the opening 101a of the conduction path 101 of the cylinder block starts to communicate with the high-pressure opening 103a to the timing when the opening 101a of the conduction path 101 starts to communicate with the opening 102a of the suction communication path 102 of the rotary valve. It is conceivable to reduce the time difference.

Therefore, the seal region S needs to close the opening 101a of the cylinder block conduction path 101. Therefore, simply reducing the seal area S will reduce the opening 101a force S of the conduction path 101. If the opening 101a is small, the loss of gas suction into the compression chamber increases, which is not preferable because the compression efficiency decreases.

Patent Document 1: JP 2004-239210 A

Disclosure of the invention

[0008] An object of the present invention is to provide a piston type compressor capable of improving the compression efficiency by suppressing the suction loss of the gas into the compression chamber while advancing the gas suction start timing into the compression chamber. is there.

[0009] According to one aspect of the present invention, a rotating shaft and a plurality of the rotating shafts arranged around the rotating shaft. There is provided a piston type compressor including a cylinder block having a number of cylinder bores, a piston accommodated in each cylinder bore, and a rotary valve that rotates in synchronization with the rotary shaft. The piston defines a compression chamber within the cylinder bore. The cylinder block has a plurality of suction ports that communicate the suction pressure regions with the compression chambers. The piston is reciprocated between a bottom dead center that maximizes the volume of the compression chamber and a top dead center that minimizes the volume of the compression chamber, whereby the suction pressure via the rotary valve is increased. Gas is sucked into the compression chamber from a region, gas is compressed in the compression chamber, and gas is discharged from the compression chamber. The rotary valve has a suction communication passage and a residual gas bypass passage. As the rotary valve rotates, the suction communication passage sequentially connects each suction port to the suction pressure region. The residual gas bypass passage connects the suction port corresponding to the high-pressure side compression chamber after completion of the discharge to the suction port corresponding to the low-pressure side compression chamber. The portion of the outer peripheral surface of the rotary valve that faces the opening of the suction port constitutes a seal region that prevents the residual gas bypass passage from communicating with the suction communication passage through the opening of the suction port.

Each of the suction ports has a narrow passage on the top dead center side and a wide passage on the bottom dead center side. With respect to the rotation direction of the rotary valve, the width of the opening of the narrow passage facing the outer peripheral surface of the rotary valve is smaller than the width of the opening of the wide passage. The opening of the narrow passage has a first leading edge through which the suction communication passage of the rotating rotary valve passes first, and a first trailing edge through which it passes thereafter. The opening of the wide passage has a second leading edge through which the suction communication passage of the rotating rotary valve passes first, and a second trailing edge through which it passes thereafter. The suction communication path passes through the first trailing edge before the second trailing edge. The residual gas bypass passage has a high pressure opening. The high pressure opening faces only the narrow passage of the suction port when communicating with the suction port corresponding to the compression chamber on the high pressure side. The narrow passage is arranged so as to communicate with a compression chamber defined by a piston located at the top dead center. Regarding the rotational direction of the rotary valve, the width between the first trailing edge and the second leading edge is determined by the dimension of the portion of the seal region between the high-pressure opening and the opening of the suction communication passage. Is also small. Immediately after the narrow passage is blocked by the seal region, the opening of the suction communication passage communicates with the wide passage. It is.

[0011] Each suction port may have a wide passage on the top dead center side and a narrow passage on the bottom dead center side.

. The wide passage may be connected to the narrow passage.

Brief Description of Drawings

FIG. 1 is a longitudinal sectional view showing a piston compressor according to a first embodiment that embodies the present invention.

FIG. 2 is a sectional view taken along line 11 in FIG.

FIG. 3 is a diagram showing the outer peripheral surface of the rotary valve in FIG.

FIG. 4 is a development view showing a state in which the narrow passage in FIG. 3 is blocked by a seal region.

FIG. 5 is a development view showing a state where the suction port communicates with the suction communication passage.

FIG. 6 is a diagram showing an outer peripheral surface of a rotary valve according to a second embodiment of the present invention developed in a planar shape.

FIG. 7 is a diagram showing an outer peripheral surface of a rotary valve according to a third embodiment of the present invention developed in a planar shape.

FIG. 8 is a development view showing another example of the intake port.

FIG. 9 is a development view showing another example of the intake port.

FIG. 10 is a development view showing another example of the intake port.

FIG. 11 is a developed view of a rotary valve showing the background art.

FIG. 12 is a developed view of a rotary valve showing the background art with a reduced seal area.

BEST MODE FOR CARRYING OUT THE INVENTION

Hereinafter, a first embodiment embodying the present invention will be described with reference to FIGS. In the following description, in the “up”, “down”, “front”, and “rear” of the piston compressor 10, the direction of the arrow Y1 shown in FIG. 1 is the vertical direction, and the direction of the arrow Y2 is the front-back direction.

As shown in FIG. 1, a piston compressor 10 includes a cylinder block 11, a front housing 12 joined to the front end of the cylinder block 11, and a rear housing joined to the rear end of the cylinder block 11. 13 and. A valve assembly 14 is disposed between the cylinder block 11 and the rear housing 13. The cylinder block 11, the front housing 12, the rear housing 13 and the valve assembly 14 are fastened and fixed to each other by a plurality of through bolts B. Figure 1 shows only one bolt B. Cylinder block 11 The front housing 12 and the rear housing 13 constitute a housing for the piston compressor 10.

A crank chamber 17 is defined in a region surrounded by the front housing 12 and the cylinder block 11 in the housing. A rotating shaft 19 is rotatably supported by the cylinder block 11 and the front housing 12. A rotating shaft 19 is disposed in the crank chamber 17. The rotary shaft 19 is operatively connected to an external drive source, for example, an engine E via a power transmission mechanism PT, and is rotated by receiving power supply from the external drive source E. The rotary shaft 19 is passed through shaft holes 20 and 21 penetrating the cylinder block 11 and the front housing 12.

The front end of the rotary shaft 19 is supported by the front housing 12 via a radial bearing 22 provided in the shaft hole 20 of the front housing 12. A lip seal type shaft seal device 23 is disposed between the front housing 12 and the rotary shaft 19. The shaft sealing device 23 prevents leakage of refrigerant gas from the crank chamber 17 along the rotary shaft 19. In the crank chamber 17, a lug plate 16 is fixed on the rotary shaft 19 so as to be rotatable. A thrust bearing 18 is disposed between the lug plate 16 and the front housing 12.

A swash plate 24 is accommodated in the crank chamber 17. The swash plate 24 is supported so as to be slidable on the rotary shaft 19 and to change the inclination angle with respect to the central axis L1 of the rotary shaft 19. A hinge mechanism 25 is disposed between the lug plate 16 and the swash plate 24. The swash plate 24 can be rotated synchronously with the lug plate 16 and the rotary shaft 19 by the hinge connection with the lug plate 16 via the hinge mechanism 25 and the support of the rotary shaft 19. Further, the swash plate 24 can tilt with respect to the rotary shaft 19 while being slid in the axial direction of the rotary shaft 19, that is, in the direction of the central axis L 1.

As shown in FIG. 2, the cylinder block 11 has a plurality of cylinder bores 11 a in this embodiment arranged around the rotary shaft 19. Each cylinder bore 11a accommodates a single-headed piston 31 so as to be able to reciprocate. The piston 31 is slidably anchored to the peripheral portion of the swash plate 24 via a pair of front and rear shoes 30. The rotation of the swash plate 24 accompanying the rotation of the rotary shaft 19 is changed to the reciprocating motion of the piston 31 via the shoe 30. Replaced.

[0019] The front and rear openings of the cylinder bore 11a are closed by a valve assembly 14 and a piston 31, respectively. In the cylinder bore 11a, a compression chamber 26 whose volume changes according to the reciprocating motion of the piston 31 is defined. In the rear housing 13, a suction passage 28 and a discharge chamber 29 are defined as suction pressure regions. The suction passage 28 is formed in the central portion of the rear housing 13. The discharge chamber 29 is formed so as to surround the outer periphery of the suction passage 28. The valve assembly 14 includes a discharge port 32 that communicates the compression chamber 26 with the discharge chamber 29 and a discharge valve 33 that opens and closes the discharge port 32.

Next, the rotary valve 41 and the residual gas bin passage will be described.

[0021] The cylinder block 11 is formed with a valve housing chamber 42 at the center surrounded by the cylinder bore 11a. A rotary valve 41 is rotatably accommodated in the valve accommodating chamber 42. A plurality of suction ports 43 formed in the cylinder block 11 communicate the valve housing chambers 42 with the respective compression chambers 26. Only one inlet port 43 is shown in FIG. The rotary valve 41 is made of an aluminum-based metal material and has a cylindrical shape. The rear end of the rotary shaft 19 is disposed in the valve storage chamber 42. The front end of the rotary valve 41 is press-fitted into the press-fit recess 19 a at the rear end of the rotary shaft 19.

[0022] The outer peripheral surface 41a of the rotary valve 41 and the peripheral surface 42a of the valve storage chamber 42 constitute a sliding bearing surface for rotatably supporting the rotary valve 41 in the valve storage chamber 42. A rear end of the rotary shaft 19 is rotatably supported by the cylinder block 11 via a rotary valve 41. The central axis L2 of the rotary valve 41 is located on the same axis as the central axis L1 of the rotary shaft 19. That is, the rotary valve 41 and the rotary shaft 19 are integrated to form a single axis. The rotary valve 41 is rotated in synchronization with the rotation of the rotary shaft 19, that is, the reciprocating motion of the piston 31.

The rotary valve 41 has an in-cylinder space 44. The in-cylinder space 44 communicates with the suction passage 28 through a through hole 14 a formed in the valve assembly 14. As shown in FIG. 2, the outer peripheral surface 41a of the rotary valve 41 extends from the in-cylinder space 44 to the peripheral wall of the rotary valve 41. A suction communication passage 45 extending up to is provided. That is, the inlet 45 a of the suction communication passage 45 opens into the in-cylinder space 44, and the outlet 45 b of the suction communication passage 45 opens on the outer peripheral surface 41 a of the rotary valve 41. Due to the rotation of the rotary valve 41 accompanying the rotation of the rotary shaft 19, the outlet 45 b of the suction communication passage 45 communicates intermittently with the opening of the suction port 43 of the cylinder block 11, that is, the inlet 43 a. In other words, the suction communication passage 45 allows the in-cylinder space 44 serving as a suction pressure region to sequentially communicate with the inlet 43a of the suction port 43 extending from each compression chamber 26 in synchronization with the rotation of the rotary valve 41.

[0024] The outlet 45b of the suction communication passage 45 of the rotary valve 41 communicates with the inlet 43a of the suction port 43 of the cylinder block 11 when the piston 31 shifts to the suction stroke. Then, the refrigerant gas in the suction passage 28 is compressed through the through hole 14a of the valve assembly 14, the cylinder space 44 of the rotary valve 41, the suction communication passage 45, and the suction port 43 of the cylinder block 11 in the same order. Inhaled into chamber 26.

In the suction stroke, the position of the piston 31 that maximizes the volume of the compression chamber 26 is defined as the bottom dead center of the piston 31. At the end of the suction stroke of the piston 31, that is, when the piston 31 is located at the bottom dead center, the outlet 45b of the suction communication passage 45 of the rotary valve 41 extends from the inlet 43a of the suction port 43 of the cylinder block 11 in the circumferential direction. It is completely off. That is, the suction of the refrigerant gas into the compression chamber 26 is also stopped in the in-cylinder space 44 force. Thereafter, when the piston 31 is shifted to the compression process and the discharge stroke, the outer peripheral surface 41a of the rotary valve 41 holds the space between the in-cylinder space 44 and the compression chamber 26 in a closed state. For this reason, the compression of the refrigerant gas and the discharge of the compressed gas into the discharge chamber 29 are not hindered. In the compression process and the discharge stroke, the position of the piston 31 that minimizes the volume of the compression chamber 26 is defined as the top dead center of the piston 31. When the piston 31 is at the top dead center, there is a so-called top clearance between the piston 31 and the valve assembly 14 in the cylinder bore 1 la. In the top clearance, there is residual gas remaining in the compression chamber 26 that cannot be completely discharged.

FIG. 3 is a diagram in which the outer peripheral surface 41a of the rotary valve 41 is developed in a planar shape. The suction port 43 of the cylinder block 11 is opposed to the outer peripheral surface 41a of the rotary valve 41. 3 to 5, the direction of arrow Y3 shown in FIG. 3 is the rotational direction of the rotary valve 41, that is, the circumferential direction. The rotary valve 41 proceeds to the left in FIG. Arrow Y4 The direction indicates the axial direction of the rotary valve 41, that is, the direction of the central axis L2.

As shown in FIG. 3, a residual gas bypass groove 46 constituting a residual gas bypass passage is formed on the outer peripheral surface 41a of the rotary valve 41. The residual gas bypass groove 46 has a high pressure groove 47, a low pressure groove 48, and a communication groove 49. The high pressure groove 47 extends in the direction of the central axis L2 of the rotary valve 41, that is, in the direction of the arrow Y4, and functions as a high pressure opening. The low-pressure groove 48 also extends in the direction of the central axis L2. The communication groove 49 extends in the circumferential direction of the rotary valve 41, that is, in the direction of the arrow Y 3, and communicates the top dead center side end of the high pressure groove 47 with that of the low pressure groove 48. That is, the communication groove 49 communicates the rear end of the high-pressure groove 47 in the piston compressor 10 with the low-pressure groove 48.

[0028] The high pressure groove 47 communicates with the suction port 43 (43A) corresponding to the compression chamber 26 on the high pressure side immediately after the end of discharge so as to communicate with the outer peripheral surface 41a of the rotary valve 41 in advance of the low pressure groove 48. Is arranged. For this reason, the high-pressure groove 47 communicates with the top clearance of the cylinder bore 11 a through the suction port 43 of the cylinder block 11. Further, the low pressure groove 48 is arranged on the outer peripheral surface 41a of the rotary valve 41 so as to face the suction port 43 (43B) corresponding to the compression chamber 26 immediately after completion of the suction, which is the compression chamber 26 on the low pressure side! .

The outer peripheral surface 41 a of the rotary valve 41 has a seal region S between the high pressure groove 47 and the suction communication path 45 of the rotary valve 41. The seal region S prevents a gas path from the high pressure groove 47 of the residual gas bypass groove 46 to the outlet 45b of the suction communication passage 45 of the rotary valve 41 through the inlet 43a of the suction port 43 of the cylinder block 11. The seal region S faces the inlet 43a of the suction port 43 on the outer peripheral surface 41a of the inlet valve 41, and makes the high-pressure groove 47 non-communication with respect to the outlet 45b of the suction communication passage 45. Residual refrigerant gas remaining in the compression chamber 26 immediately after the discharge is completed cannot be discharged into the suction port 43 (43A) of the cylinder block 11, the high pressure groove 47, the communication groove 49, the low pressure groove 48, and the cylinder port of the rotary valve 41. Via the suction port 43 (43B) of the rack 11 in the same order, it is bypassed, that is, recovered into the compression chamber 26 immediately after the end of the suction.

As shown by a two-dot chain line in FIG. 3, each suction port 43 formed in the cylinder block 11 has an opening facing the outer peripheral surface 41a of the rotary valve 41, that is, an inlet 43a. It has a shape with different opening widths Ta and Tb. Suction port 43 is connected to narrow passage 50 A wide passage 51 is provided. The narrow passage 50 is provided on the top dead center side in the direction of the central axis L2 of the rotary valve 41, and the wide passage 51 is provided on the bottom dead center side. That is, the suction port 43 has a top dead center side passage on the top dead center side and a bottom dead center side passage on the bottom dead center side. In the first embodiment, the top dead center side passage is the narrow passage 50 and the bottom dead center side passage is the wide passage 51.

[0031] The narrow passage 50 has a constant first opening width Ta in the circumferential direction of the rotary valve 41, and extends in the direction of the central axis L2. The wide passage 51 has a constant second opening width Tb in the circumferential direction and extends in the direction of the central axis L2. At the inlet 43a of the suction port 43, the first opening width Ta of the narrow passage 50 is set smaller than the second opening width Tb of the wide passage 51 (Ta <Tb).

[0032] The first opening width Ta of the narrow passage 50 is set to be smaller than the interval between the high-pressure groove 47 and the suction communication passage 45 in the circumferential direction, that is, the seal width W in a part of the seal region S. (W> Ta). On the other hand, the second opening width Tb of the wide passage 51 is set to be larger than the seal width W (W く Tb). At the inlet 43a of the suction port 43, the boundary between the narrow passage 50 and the wide passage 51 is formed in a step shape. When the rotary valve 41 rotates, the high-pressure groove 47 is configured to pass the top dead center side, that is, the lower side of FIG. For this reason, when the rotary valve 41 rotates, the high-pressure groove 47 is configured not to communicate with the wide-width passage 51 that can communicate with the narrow passage 50.

[0033] The narrow passage 50 has a first leading edge 50a and a first trailing edge 50b opposite to the first leading edge 50a with respect to the rotational direction of the rotary valve 41. When the rotary valve 41 rotates, the suction communication path 45 first passes through the first leading edge 50a and then passes through the first trailing edge 50b. Similarly, the wide passage 51 has a second leading edge 51a and a second trailing edge 5 lb on the opposite side with respect to the rotational direction of the rotary valve 41. During the rotation of the rotary valve 41, the suction communication passage 45 first passes through the second leading edge 5 la and then passes through the second trailing edge 5 lb. The first leading edge 50a side with respect to the first trailing edge 50b is called the leading side, and the opposite is called the trailing side. The second leading edge 51a side with respect to the second trailing edge 51b is called the leading side, and the opposite side is called the trailing side.

[0034] Along the rotational direction of the rotary valve 41, from the first trailing edge 50b of the narrow passage 50, the width The third opening width Tc to the second leading end edge 51a of the wide passage 51 is set to be slightly smaller than the seal width W of the seal region S. Therefore, immediately after the high-pressure groove 47 passes through the narrow passage 50, the outlet 45 b of the suction communication passage 45 communicates with the wide passage 51.

FIG. 3 shows a time point when the compression chamber 26 corresponding to the suction port 43A is immediately after the end of the discharge, and the piston 31 in the compression chamber 26 on the high pressure side is at the top dead center. At this time, the high-pressure groove 47 passes through the top dead center side with respect to the wide passage 51. That is, the high pressure groove 47 communicates only with the narrow passage 50 at the inlet 43 a of the suction port 43, and does not communicate with the wide passage 51. The wide passage 51 at the inlet 43 a of the suction port 43 is blocked by the seal region S. The residual refrigerant gas remaining in the top clearance without being discharged in the compression chamber 26 is the suction port 43A of the cylinder block 11, the high pressure groove 47 of the rotary valve 41, the communication groove 49, the low pressure groove 48, and the suction port of the cylinder block 11. Via 43B in the same order, it is bypassed, that is, recovered to the compression chamber 26 immediately after the end of the suction. For this reason, the re-expansion of the residual gas is reduced when the compression chamber 26 corresponding to the suction port 43A performs the suction stroke. Therefore, the refrigerant gas in the in-cylinder space 44 can be reliably sucked into the compression chamber 26, and the volumetric efficiency of the piston compressor 10 can be improved.

Thereafter, as shown in FIG. 4, when the rotary valve 41 rotates and the high-pressure groove 47 passes through the narrow passage 50, the narrow passage 50 at the inlet 43a of the suction port 43 becomes the seal region S. It is blocked by. At this time, the wide passage 51 at the inlet 43a of the suction port 43 is already closed by the seal region S. For this reason, the narrow passage 50 and the wide passage 51, that is, the inlet 43 a whole force sealing region S of the suction port 43 is blocked. Therefore, the seal region S prevents a gas path that leads to the inlet 43a of the suction port 43 between the high-pressure groove 47 and the outlet 45b of the suction communication passage 45.

When the rotary valve 41 is slightly rotated from the state shown in FIG. 4, the outlet 45 b of the suction communication passage 45 is connected to the wide passage 51. That is, immediately after the high-pressure groove 47 passes through the narrow passage 50, in other words, immediately after the high-pressure groove 47 is disconnected from the inlet 43a of the suction port 43A, the outlet 45b force of the suction communication passage 45 is sucked into the suction port. It communicates with 43A entrance 43a. FIG. 5 shows a state in which the rotary valve 41 further rotates and both the narrow passage 50 and the wide passage 51 communicate with the suction communication passage 45 of the rotary valve 41. After that, the rotary valve 41 When rotated, the entire inlet 43a of the suction port 43A, that is, the entire narrow passage 50 and the wide passage 51 communicates with the outlet 45b of the suction communication passage 45. The refrigerant gas in the suction passage 28 passes through the through hole 14a of the valve assembly 14, the in-cylinder space 44 of the rotary valve 41, the suction communication passage 45, and the suction port 43A of the cylinder block 11 in the same order, and the compression chamber 26 Inhaled.

[0038] The first embodiment has the following advantages.

(1) The inlet 43a of the suction port 43 has a narrow passage 50 on the top dead center side and a wide passage 51 on the bottom dead center side. That is, the width Ta on the top dead center side of the inlet 43a of the suction port 43 along the rotational direction, that is, the circumferential direction of the rotary valve 41 is set smaller than the width Tb on the bottom dead center side. The high pressure groove 47 is configured to communicate with only the narrow passage 50 when the rotary valve 41 rotates. Since the width Ta of the opening of the narrow passage 50 is smaller than the width Tb of the opening of the wide passage 51, the seal width W of the seal region S for gas path prevention can be reduced. Therefore, the dimension between the high pressure groove 47 and the outlet 45b of the suction communication passage 45 of the rotary valve 41 can be reduced. As a result, from the timing when the high pressure groove 47 of the rotary valve 41 starts to communicate with the suction port 43A of the cylinder block 11 through the narrow passage 50, the suction communication passage 45 of the rotary valve 41 becomes wider with the suction port 43A of the cylinder block 11. The time difference until the start of communication at 51 can be reduced. That is, the time from the recovery of the gas remaining in the high-pressure side compression chamber 26 corresponding to the suction port 43A until the refrigerant gas is sucked into the compression chamber 26, that is, the suction start timing of the compression chamber 26 is reduced. can do.

[0040] In order to prevent a gas path from the high-pressure groove 47 to the suction communication passage 45, the seal region S only needs to close the narrow passage 50. Therefore, the suction port 43 can have a wide passage 51 in addition to the narrow passage 50. For this reason, even if the seal width W of the seal region S is set small in order to advance the start timing of the refrigerant gas suction into the compression chamber 26, an increase in the refrigerant gas suction loss is suppressed. As a result, it is possible to improve the compression efficiency by suppressing the amount of gas suction loss while speeding up the start of the suction of the refrigerant gas into the compression chamber 26.

(2) The narrow passage 50 is connected to the wide passage 51 at the inlet 43 a of the suction port 43.

For this reason, for example, compared with the case where the narrow passage 50 is partitioned from the wide passage 51, the amount of refrigerant gas sucked into the compression chamber 26 from the inlet 43a of the suction port 43 can be increased. (3) As shown in FIG. 3, when the piston 31 is located at the top dead center, the narrow passage 50 at the inlet 43a of the suction port 43 is directly communicated with the compression chamber 26. Therefore, when the high-pressure groove 47 communicates with the narrow passage 50, the residual gas in the compression chamber 26 is quickly collected in the high-pressure groove 47. Therefore, the residual gas can be reliably recovered. As a result, the remaining gas re-expansion during the suction stroke is reduced, and the refrigerant gas is reliably sucked into the compression chamber 26. Therefore, the volumetric efficiency of the piston compressor 10 can be improved.

[0043] Next, a piston compressor according to a second embodiment embodying the present invention will be described with reference to FIG. Note that the second embodiment has a configuration in which only the suction port 43 is changed in the piston type compressor 10 of the first embodiment, and therefore, duplicate description of the same parts is omitted.

[0044] As shown in FIG. 6, in the inlet 43a of the suction port 43 of the second embodiment, the narrow passage 50 is formed to be biased toward the leading side in the rotational direction of the rotary valve 41 with respect to the wide passage 51. It is. In other words, the narrow passage 50 is arranged to be biased toward the second leading edge 51a with respect to the wide passage 51. In the second embodiment, the first leading edge 50a of the narrow passage 50 is located on the same straight line as the second leading edge 51a of the wide passage 51. The first opening width Ta of the narrow passage 50 and the second opening width Tb of the wide passage 51 of the second embodiment are set to be the same as those of the first embodiment.

[0045] The seal width W of the seal region S between the high-pressure groove 47 and the suction communication passage 45 is set to be slightly larger than the third opening width Tc. The third opening width Tc, which is the dimension from the first trailing edge 50b of the narrow passage 50 to the second leading edge 51a of the wide passage 51, is the first width of the narrow passage 50 in the second embodiment. Equal to the dimension from the trailing edge 50b to the first leading edge 50a (Ta = Tc). Thus, the seal width W of the seal region S in the second embodiment is set to be smaller than that in the first embodiment.

[0046] The second embodiment further has the following advantages.

[0047] (4) As shown in FIG. 6, the narrow passage 50 of the second embodiment is arranged closer to the first leading edge 50a of the wide passage 51 than the first embodiment. Has been. The seal width W of the second embodiment is set smaller than that of the first embodiment. Therefore, the dimension between the high pressure groove 47 and the outlet 45b of the suction communication passage 45 can be further reduced. That As a result, from the timing when the high pressure groove 47 of the rotary valve 41 starts to communicate with the narrow passage 50 of the cylinder block 11 to the timing when the suction communication passage 45 of the rotary valve 41 starts to communicate with the suction port 43 of the cylinder block 11. Time can be further reduced. As a result, the amount of gas suction loss into the compression chamber 26 can be reduced.

[0048] Next, a piston compressor according to a third embodiment of the present invention will be described with reference to FIG. In the third embodiment, in the first embodiment, the positional relationship between the narrow passage 50 and the wide passage 51 is reversed between the top dead center side and the bottom dead center side so that the suction port 43 and the residual gas bypass groove 46 The positional relationship is reversed between the top dead center side and the bottom dead center side. For the same part, duplicate explanation is omitted.

[0049] As shown in FIG. 7, on the outer peripheral surface 41a of the rotary valve 41, the high pressure groove 47 and the low pressure groove 48 of the residual gas bypass groove 46 are connected to the suction port 43 with respect to the central axis L2 direction of the rotary valve 41. It is provided on the bottom dead center side. That is, the high-pressure groove 47 as a high-pressure opening is disposed on the front side of the piston compressor 10 with respect to the suction port 43. The communication groove 49 of the residual gas bypass groove 46 communicates the end of the high pressure groove 47 and the low pressure groove 48 on the bottom dead center side. That is, the communication groove 49 communicates the front end portions of the high-pressure groove 47 and the low-pressure groove 48 in the piston-type compressor 10.

[0050] As shown by a two-dot chain line in FIG. 7, the inlet 43a of each suction port 43 formed in the cylinder block 11 has two kinds of opening widths Ta and Tb in the circumferential direction. That is, the opening of the suction port 43 facing the outer peripheral surface 41a of the rotary valve 41 has two types of opening widths Ta and Tb. The inlet 43a of the suction port 43 has the narrow passage 50 on the bottom dead center side and the wide passage 51 on the top dead center side in the direction of the central axis L2 of the rotary valve 41. The narrow passage 50 has a first opening width Ta having a constant dimension in the circumferential direction of the rotary valve 41, and extends in the direction of the central axis L2. The wide passage 51 extends in the direction of the central axis L2 with a second opening width Tb having a constant dimension in the circumferential direction.

[0051] The first opening width Ta of the narrow passage 50 is set smaller than the seal width W of the seal region S (W> Ta). The second opening width Tb of the wide passage 51 is set to be larger than the seal width W of the seal region S (W <Tb). The narrow passage 50 is connected to the wide passage 51 at the inlet 43 a of the suction port 43. The boundary between narrow passage 50 and wide passage 51 is It is formed in a step shape. When the rotary valve 41 rotates, the high-pressure groove 47 is disposed so as to pass through the bottom dead center side with respect to the wide passage 51, that is, above the upper side in FIG. Therefore, when the single valve 41 rotates, the high-pressure groove 47 communicates with the narrow passage 50 but does not communicate with the wide passage 51.

[0052] The third opening width Tc along the circumferential direction from the first trailing edge 50b of the narrow passage 50 to the second leading edge 51a of the wide passage 51 is the seal width W of the seal region S. It is set slightly smaller than. Therefore, immediately after the high pressure groove 47 passes through the narrow passage 50, the outlet 45 b of the suction communication passage 45 communicates with the wide passage 51. In the compression chamber 26 immediately after the end of the discharge with the piston 31 at the top dead center, a wide passage 51 arranged directly below the bottom dead center in FIG.

[0053] The third embodiment further has the following advantages.

(5) The wide passage 51 is formed on the top dead center side with respect to the narrow passage 50 in the direction of the central axis L2 of the rotary valve 41. Therefore, compared with the case of the first embodiment, in the third embodiment, the suction port 43 of the cylinder block 11 communicated with the suction communication passage 45 of the rotary valve 41 at the start of the suction of the refrigerant gas into the compression chamber 26. The area can be increased. Therefore, the amount of gas sucked into the compression chamber 26 can be increased. In the first embodiment, the narrow passage 50 is formed on the top dead center side of the wide passage 51, and the first leading edge 50a of the narrow passage 50 is more than the second leading edge 51a of the wide passage 51. Was also formed on the trailing side.

[0055] The above embodiments may be modified as follows! /.

[0056] As shown in FIG. 8, in each embodiment, the narrow passage 50 may be composed of a plurality of small passage caps separated from each other. The first opening width Ta of the narrow passage 50 is a dimension between the first leading edge 50a of the most preceding small passage and the first trailing edge 50b of the most trailing small passage. . Since the first leading edge 50a and the second leading edge 51a are on the same line, Ta = Tc. The third opening width Tc may be set to be smaller than the seal width W between the high pressure groove 47 and the suction communication passage 45.

As shown in FIG. 9, in the first and second embodiments, the narrow passage 50 may be formed in a pair of long holes. That is, the shape of the narrow passage 50 is not limited to the shape of the first to third embodiments, and may be, for example, an elliptical hole shape or a round hole shape. As shown in FIG. 9, the narrow passage 50 may be separated from the wide passage 51. For example, the narrow passage 50 includes two long hole-like small passages extending in the circumferential direction of the rotary valve 41. The first leading edge 50a is the most leading edge of the plurality of small passages, and the first trailing edge 50b is the most trailing edge of the plurality of small passages. The third opening width Tc of the narrow passage 50 is a dimension between the second leading edge 51a of the wide passage 51 and the first trailing edge 50b of the narrow passage 50. The third opening width Tc only needs to be smaller than the seal width W between the high pressure groove 47 and the suction communication path 45.

As shown in FIG. 10, the opening width, that is, the circumferential dimension of the wide passage 51 may be reduced as the narrow passage 50 is approached. In the case of FIG. 10, the second leading edge 5 la and the second trailing edge 51b of the wide passage 51 are formed of a portion where the opening width of the wide passage 51 is maximum, that is, an end on the bottom dead center side.

In the third embodiment, the narrow passage 50 may be formed so as to be biased toward the leading side in the rotational direction of the rotary valve 41 with respect to the wide passage 51, that is, closer to the second leading edge 5 la. The first leading edge 50a of the narrow passage 50 may be positioned on the same straight line as the second leading edge 51a of the wide passage 51.

[0061] In each embodiment, the shape of the outlet of the suction port 43 and the shape of the passage inside the suction port 43 are arbitrary if the suction port 43 includes the narrow passage 50 and the wide passage 51 in the inlet 43a. You may change to

[0062] In each of the embodiments, the narrow passage 50 is not limited as long as the first trailing edge 50b of the narrow passage 50 is positioned ahead of the second trailing edge 51b of the wide passage 51. It may be biased toward the trailing side with respect to the wide passage 51.

[0063] The present invention may be applied to a double-headed piston compressor.

Claims

The scope of the claims

A rotating shaft (19), a cylinder block (11) having a plurality of cylinder bores (11a) arranged around the rotating shaft (19), and a piston (31) accommodated in each cylinder bore (11a), A piston type compressor comprising a rotary valve (41) that rotates synchronously with the rotary shaft (19),

The piston (31) defines a compression chamber (26) in the cylinder bore (11a), and the cylinder block (11) has a plurality of suction ports that respectively connect the suction pressure region (28) to the compression chamber (26). And a piston (31) between a bottom dead center that maximizes the volume of the compression chamber (26) and a top dead center that minimizes the volume of the compression chamber (26). By being reciprocated, the suction of the gas from the suction pressure region (28) to the compression chamber (26) through the single valve (41), the compression of the gas in the compression chamber (26), In addition, gas is discharged from the compression chamber (26),

The rotary valve (41) has a suction communication passage (45) and a residual gas bin passage (46). When the rotary valve (41) rotates, the suction communication passage (45) is connected to each suction port. (43) is sequentially communicated to the suction pressure region (28), and the residual gas bypass passage (46) connects the suction port (43A) corresponding to the high-pressure side compression chamber (26) after the end of discharge to the low-pressure side. The portion of the outer peripheral surface (41a) of the rotary valve (41) that communicates with the suction port (43B) corresponding to the compression chamber (26) and faces the opening (43a) of the suction port (43) In comparison with a piston type compressor that constitutes a seal region (S) that prevents the gas bypass passage (46) from communicating with the suction communication passage (45) through the opening (43a) of the suction port (43). Each of the suction ports (43) has a narrow passage (50) on the top dead center side and a wide passage (51) on the bottom dead center side, and the rotary valve The opening width (Ta) of the narrow passage (50) facing the outer peripheral surface (41a) of the rotary valve (41) with respect to the rotational direction of the hub (41) is the width of the opening of the wide passage (51). Smaller than (Tb)

The opening of the narrow passage (50) includes a first leading edge (50a) through which the suction communication passage (45) of the rotating rotary valve (41) passes first, and a first following passage through which the passage follows. And the opening of the wide passage (51) has a second leading edge (51a) through which the suction communication passage (45) of the rotating rotary valve (41) passes first, and thereafter With a second trailing edge (51b) passing through Have

The suction communication passage (45) passes through the first trailing edge (50b) before the second trailing edge (51b),

The residual gas bypass passage (46) has a high pressure opening (47), and the high pressure opening (47) is connected to the suction port (43A) corresponding to the compression chamber (26) on the high pressure side. (4 3A) facing only the narrow passage (50),

The narrow passage (50) is arranged so as to be able to communicate with a compression chamber (26) defined by a piston (31) located at the top dead center,

With respect to the rotational direction of the rotary valve (41), the width (Tc) between the first trailing edge (50b) and the second leading edge (51a) is the same as the high pressure opening (47) and the suction channel. Immediately after the narrow passage (50) is closed by the sealing region (S), which is smaller than the dimension (W) of the portion of the sealing region (S) between the opening (45b) of the passage (45). Further, an opening (45b) of the suction communication passage (45) communicates with the wide passage (51).

[2] The piston compressor according to claim 1, wherein the wide passage (51) is connected to the narrow passage (50).

[3] The piston type compressor according to claim 1 or 2, wherein the narrow passage (50) is arranged so as to be biased toward the second leading edge (51b) with respect to the wide passage (51).

4. The piston type compressor according to claim 3, wherein the first leading edge (50a) and the second leading edge (51a) are located on the same straight line.

[5] A rotating shaft (19), a cylinder block (11) having a plurality of cylinder bores (11a) arranged around the rotating shaft (19), and a piston (3 1) accommodated in each cylinder bore (11a) ) And a rotary valve (41) that rotates synchronously with the rotary shaft (19),

The piston (31) defines a compression chamber (26) in the cylinder bore (11a), and the cylinder block (11) has a plurality of suction ports that respectively connect the suction pressure region (28) to the compression chamber (26). And a piston (31) between a bottom dead center that maximizes the volume of the compression chamber (26) and a top dead center that minimizes the volume of the compression chamber (26). By being reciprocated, the gas from the suction pressure region (28) through the inlet valve (41) to the compression chamber (26) is transferred. Inhalation, gas compression in the compression chamber (26), and gas discharge from the compression chamber (26) are performed,

The rotary valve (41) has a suction communication passage (45) and a residual gas bin passage (46). When the rotary valve (41) rotates, the suction communication passage (45) is connected to each suction port. (43) is sequentially communicated to the suction pressure region (28), and the residual gas bypass passage (46) connects the suction port (43A) corresponding to the high-pressure side compression chamber (26) after the end of discharge to the low-pressure side. The portion of the outer peripheral surface (41a) of the rotary valve (41) that communicates with the suction port (43B) corresponding to the compression chamber (26) and faces the opening (43a) of the suction port (43) In comparison with a piston type compressor that constitutes a seal region (S) that prevents the gas bypass passage (46) from communicating with the suction communication passage (45) through the opening (43a) of the suction port (43). Each of the suction ports (43) has a wide passage (51) on the top dead center side and a narrow passage (50) on the bottom dead center side, and the rotary valve The opening width (Ta) of the narrow passage (50) facing the outer peripheral surface (41a) of the rotary valve (41) with respect to the rotational direction of the hub (41) is the width of the opening of the wide passage (51). Smaller than (Tb)

The opening of the narrow passage (50) includes a first leading edge (50a) through which the suction communication passage (45) of the rotating rotary valve (41) passes first, and a first following passage through which the passage follows. And the opening of the wide passage (51) has a second leading edge (51a) through which the suction communication passage (45) of the rotating rotary valve (41) passes first, and thereafter And a second trailing edge (51b) passing through

The residual gas bypass passage (46) has a high-pressure opening (47), and the high-pressure opening (47) is connected to the suction port (43A) corresponding to the compression chamber (26) on the high-pressure side. Facing only the narrow passage (50) of the port (43A),

The wide passage (51) is connected to the narrow passage (50), and the wide passage (51) communicates with the compression chamber (26) defined by the piston (31) located at the top dead center. Arranged as possible,

Regarding the rotational direction of the rotary valve (41), the first trailing edge (50b) and the second tip The width (Tc) between the row end edge (51a) is the dimension of the portion of the seal region (S) between the high-pressure opening (47) and the opening (45b) of the suction communication passage (45) ( Immediately after the narrow passage (50) is closed by the seal region (S), the opening (45b) of the suction communication passage (45) communicates with the wide passage (51). A piston type compressor characterized by that.

6. The piston type compressor according to claim 5, wherein the narrow passage (50) is arranged to be biased toward the second leading edge (51b) with respect to the wide passage (51).

The piston type compressor according to claim 6, wherein the first leading edge (50a) and the second leading edge (51a) are located on the same straight line.