JP4540508B2 - Fluid machinery - Google Patents

Description

  The present invention relates to a fluid machine, and more particularly to a fluid machine that includes a scroll-type compression unit and a non-scroll type expansion device and is suitable for a vehicle air conditioning system.

  In recent years, in order to improve vehicle fuel efficiency, vehicle air conditioning systems and fuel cell systems have been required to reduce power, and in order to meet this demand, fluid machines have been developed in which a compression unit and an expansion unit are integrated and interlocked with each other. ing. When this type of fluid machine is applied to a vehicle air conditioning system or a fuel cell system, the power consumed by the entire system is reduced by operating the compression unit using the power recovered by the expansion unit as auxiliary power. (For example, refer to Patent Document 1 and Patent Document 2).

Also, if a waste heat recovery cycle (Rankine cycle) is adopted in the vehicle air conditioning system and an expansion unit is applied to the waste heat recovery cycle, the compression unit of the refrigeration cycle can be operated with the power obtained by the expansion unit. The power consumption of the vehicle air conditioning system can be reduced (see, for example, Patent Document 3).
On the other hand, a scroll type compressor applied to a vehicle air conditioning system includes a compressor provided with a capacity changing means (see, for example, Patent Document 4). The variable capacity means has a return path extending from the discharge chamber of the compressor to the suction chamber and a control valve capable of opening and closing the return path, and opens the control valve to return the discharge chamber to the suction chamber. A part of the refrigerant is recirculated through the passage, thereby suppressing an increase in the refrigerant circulation amount due to an increase in the engine speed.
JP 2004-301456 A JP 2001-355588 JP 2004-293310 A JP-A-2-204694

  By the way, since the scroll compressor is superior in terms of quietness and miniaturization as compared with a reciprocating compressor, the demand for the scroll compressor is increasing. However, the above-described fluid machine of Patent Document 2 has a complicated configuration in which the movable scroll is supported by two rotating shafts arranged on both sides in the radial direction even if the compression unit is a scroll type. Is difficult.

  On the other hand, in the scroll compressor of Patent Document 4 described above, since the refrigerant that has become hot due to compression is recirculated as it is, the temperature of the compression chamber rises as the refrigerant recirculation amount increases. Since overheating of the compression chamber causes a decrease in the durability of the fluid machine, this compressor has to limit the refrigerant recirculation amount, and as a result, the variable range of the refrigerant recirculation amount by the capacity varying means is narrow. Therefore, in this compressor, the increase in the refrigerant circulation amount due to the increase in the engine speed cannot be sufficiently suppressed.

The present invention has been made based on the above circumstances, and one of its purposes is to provide an expansion device with a simple configuration in addition to a scroll-type compression unit, which can reduce power consumption and is compact. The object is to provide a fluid machine suitable for production.
Another object of the present invention is to provide a fluid machine having a capacity variable means having a wide variable range and having excellent durability.

In order to achieve the above object, according to the present invention, the housing has a fixed and movable spiral wall provided in the housing and cooperating with each other to form a compression chamber. includes a scroll type compression unit suction hole is provided in communication with the chamber, an expansion device disposed between the compressor unit and the housing, a supply path and discharge path of the working fluid to the expansion device, The expansion device includes an inner peripheral wall that surrounds the outer side of the compression unit, an outer peripheral wall that is provided surrounding the inner peripheral wall, and that rotates relative to the inner peripheral wall in conjunction with the operation of the compression unit; A movable vane capable of partitioning a space between the outer peripheral wall and the inner peripheral wall in the circumferential direction and forming an expansion chamber whose volume increases or decreases with the relative swirl movement between the peripheral walls, and the movable vane. A synchronous switching means for opening and closing the supply path in synchronization with the formed the expansion chamber volume changes in, that open the return path and the return path of the working fluid extending across the suction hole from the discharge hole of the compression chamber And a variable capacity means that can return a part of the working fluid discharged from the discharge hole to the suction hole through the return path, and the expansion chamber has the supply path and the discharge path. In addition , a fluid machine is provided in which the reflux path is formed (claim 1).

As a preferred aspect, the inner peripheral wall is provided integrally with one of the spiral walls ( Claim 2 ).

As a preferred aspect, the capacity control valve is provided in the supply path ( Claim 3 ).
As a preferred embodiment, the expansion device further comprises a biasing means for biasing the movable vanes in the protruding direction on the basis of the pressure difference between said expansion chamber and said supply path (Claim 4).
As a preferred aspect, the movable vane has an end surface that comes into sliding contact with an end wall of the expansion chamber in association with the relative swiveling motion, and the supply path is a recess provided in the end surface of the movable vane. And a pocket formed in the end wall of the expansion chamber, the pocket intermittently traversing the recess of the movable vane with the relative swiveling motion to constitute the synchronous opening and closing means. It is formed in the area | region of an end wall ( Claim 5 ).

As a preferred aspect, the inner peripheral wall and the outer peripheral wall have a height different from the height of the spiral wall ( claim 6 ).

In the fluid machine according to the first to sixth aspects of the present invention, the expansion chamber is formed with a simple configuration using the inner peripheral wall, the outer peripheral wall, and the movable vane outside the scroll type compression unit having the compression chamber. Therefore, these fluid machines are suitable for miniaturization.
And in these fluid machines, the volume of the expansion chamber increases or decreases with the relative swirling motion of the inner peripheral wall and the outer peripheral wall, that is, in conjunction with the operation of the compression unit, but the high-pressure refrigerant introduced into the expansion chamber is A turning force is applied to the peripheral wall in a direction that increases the volume of the expansion chamber. Since the direction of the turning force is the same as the turning direction of the movable scroll, it becomes auxiliary power for operating the movable scroll, that is, the compression unit. Therefore, according to these fluid machines, the compression unit can obtain auxiliary power from the expansion device and can reduce power.

Especially, since the working fluid is recirculated by capacity changing means is a low temperature and expanded in the expansion chamber, together with an increase in the temperature of the working fluid supplied to the compression chamber is prevented, the compression chamber expansion chamber outside It is cooled by. Therefore, even if the amount of recirculation of the working fluid is large, the compression chamber is not overheated, and the capacity variable means can recirculate a larger amount of the working fluid, and the variable range is widened. Further, since the overheating of the compression chamber is prevented, the durability of the fluid machine is not lowered.

According to the fluid machine of claim 2 , when the inner peripheral wall of the expansion device is cooled by the expanded low-temperature working fluid, the spiral wall of the compression unit integrated with the inner peripheral wall is efficiently cooled. Chamber overheating is more reliably prevented.
According to the fluid machine of the third aspect , when the displacement control valve is closed, the supply of the working fluid to the expansion chamber is shut off, and the pressure of the working fluid in the expansion chamber passes through the discharge path through the suction hole of the compression chamber. Is equal to the pressure of the working fluid. Therefore, when the capacity control valve is closed, the high-pressure working fluid does not stay in the expansion chamber, and the working fluid in the expansion chamber becomes a load to prevent the operation of the compression unit from being hindered.

According to the fluid machine of claim 4 , since the urging means urges the movable vane due to the pressure difference between the expansion chamber and the supply path, the number of parts can be reduced. Productivity can be improved and prices can be reduced.
According to the fluid machine of the fifth aspect , since the synchronous opening / closing means of the supply path is configured by the pocket of the end wall of the expansion chamber and the recess of the movable vane, it is easy to synchronize the opening / closing timing with the increase / decrease of the volume of the expansion chamber. In addition, since a separate member is not required, the number of parts can be reduced, thereby improving productivity and reducing costs.

According to the fluid machine of claim 6 , the ratio of the expansion chamber capacity to the compression chamber capacity can be easily changed by adjusting the ratio of the height of the inner peripheral wall and the outer peripheral wall to the height of the spiral wall. The optimal volume ratio can be obtained according to the application.

FIG. 1 shows an outline of a refrigeration cycle constituting a vehicle air conditioning system, and the refrigeration cycle has a circulation passage 2 through which a refrigerant circulates. A fluid machine 4, a condenser 6, a receiver 8, an expansion valve 10, and an evaporator 12 of one embodiment as a variable capacity compressor are sequentially inserted in the circulation flow path 2 of the refrigeration cycle.
As shown in FIG. 2, the housing 14 of the fluid machine 4 includes a drive casing 16 and a compression casing 18, and the casings 16 and 18 are coupled to each other via a connecting bolt (not shown).

  A drive shaft 20 is disposed in the drive casing 16, one end of the drive shaft 20 located on the compression casing 18 side is formed as a large-diameter end 22, and the other end of the drive shaft 20 is the drive casing 16. Protruding from. The drive shaft 20 is rotatably supported by the drive casing 16 via a needle bearing 26 and a ball bearing 28, but the needle bearing 26 is disposed between the large diameter end portion 22 and the drive casing 16. A lip seal 30 is attached to an intermediate portion of the drive shaft 20 extending between the needle bearing 26 and the ball bearing 28, and the lip seal 30 partitions the inside of the drive casing 16 in an airtight manner.

  A drive pulley 34 is rotatably supported on the outside of the drive casing 16 via a bearing 32, and a drive belt 40 is looped between the drive pulley 34 and a vehicle engine 38. The drive pulley 34 constitutes a drive side unit of the electromagnetic clutch 36, while the driven side unit of the electromagnetic clutch 36 is attached to the other end portion of the drive shaft 20. Therefore, when the electromagnetic clutch 36 is turned on while the engine 38 is being driven, the drive shaft 20 rotates integrally with the drive pulley 34.

In the fluid machine 4, a scroll type compression unit 40 is accommodated in the compression casing 18, and an expansion device 41 is provided between the peripheral wall 18 a of the compression casing 18 and the compression unit 40.
More specifically, the compression unit 40 includes a movable scroll 42 and a fixed scroll 44. The movable and fixed scrolls 42, 44 are substrates 42a, 44a and spirals integrally formed on the front surfaces of the substrates 42a, 44a, respectively. And walls 42b and 44b. A boss 46 projects integrally from the back surface of a substrate 42 a (hereinafter also referred to as a movable substrate) of the movable scroll 42, and an eccentric bush 50 is attached to the inside of the boss 46 via a needle bearing 48.

  The large-diameter end 22 of the drive shaft 20 and the eccentric bush 50 are connected via a crank pin 52, and the rotation of the drive shaft 20 is movable scroll through the needle bearing 48, the eccentric bush 50 and the crank pin 52. 42 is converted into a turning motion. A ball-type orbiting thrust bearing 54 having a function of preventing the rotation of the movable scroll 42 is disposed between the movable substrate 42 a and the drive casing 16, and a counterweight 56 is attached to the eccentric bush 50.

  Here, as shown in FIG. 3, the movable substrate 42a has a circular shape, and a peripheral wall constituting the expansion device 41 (hereinafter referred to as an outer peripheral wall, denoted by reference numeral 42c) is formed on the front surface of the movable substrate 42a. Has been. The outer peripheral wall 42c protrudes from the outer peripheral edge of the movable substrate 42a in the axial direction to surround the spiral wall 42b, and the distal end surfaces of the outer peripheral wall 42c and the spiral wall 42b are located within a reference plane parallel to the movable substrate 42a. A pocket 58 that is recessed in the shape of a long hole is formed at a predetermined position on the front surface of the movable substrate 42a.

  The fixed scroll 44 is fixed in the compression casing 18 via a plurality of fixing bolts (not shown). As shown in FIG. 4, the substrate 44a (hereinafter also referred to as a fixed substrate) of the fixed scroll 44 is also circular. Make. A thick portion 44d is formed integrally with the spiral wall 44b on the front surface of the fixed substrate 44a, and the tip surfaces of the spiral wall 44b and the thick portion 44d are located in a reference plane parallel to the fixed substrate 44a. The outer peripheral surfaces of the spiral wall 44b and the thick portion 44d are cylindrical, and form a peripheral wall (hereinafter referred to as an inner peripheral wall, denoted by reference numeral 44c) that surrounds the spiral wall 44b.

The inner peripheral wall 44c also constitutes the expansion device 41, and the inner peripheral wall 44c is formed coaxially with respect to the fixed substrate 44a. The outer diameter of the inner peripheral wall 44c is smaller than the inner diameter of the outer peripheral wall 42c of the movable scroll 42, and the inner peripheral wall 44c is surrounded by the outer peripheral wall 42c (see FIG. 2).
Here, the movable substrate 42a is decentered by a distance substantially equal to the turning radius R of the movable scroll 42 with respect to the fixed substrate 44a, and the difference between the outer diameter of the inner peripheral wall 44c and the inner diameter of the outer peripheral wall 42c is It is approximately equal to twice the radius R. Therefore, the inner peripheral wall 44c is slidably contacted with the outer peripheral wall 42c at one place when viewed from the inner side in the circumferential direction, and a crescent-shaped space is defined between the inner peripheral wall 44c and the outer peripheral wall 42c. The crescent-shaped space moves around the inner peripheral wall 44c as the outer peripheral wall 42c rotates relative to the inner peripheral wall 44c as the movable scroll 42 rotates.

  Further, the outer diameter of the fixed substrate 44a is larger than the outer diameter of the outer peripheral wall 42c of the movable scroll 42 by a size approximately equal to twice the turning radius R, and the heights of the inner peripheral wall 44c and the outer peripheral wall 42c are Are equal to each other (see FIG. 2). For this reason, when the crescent-shaped space moves around the inner peripheral wall 44c, the tip surfaces of the inner peripheral wall 44c and the outer peripheral wall 42c are always in sliding contact with the front surface of the movable substrate 42a or the fixed substrate 44a. That is, when viewed in the axial direction of the inner peripheral wall 44c and the outer peripheral wall 42c, both ends of the crescent-shaped space are always closed by the movable substrate 42a and the fixed substrate 44a.

  A spiral space is defined between the spiral walls 44b of the fixed scroll 44. The outer end of the spiral space is closed by a thick portion 44d. When viewed in the spiral direction, the spiral wall 42b of the movable scroll 42 is shorter than the spiral wall 44b of the fixed scroll 44 by a length corresponding to a central angle of 180 °, and the spiral wall 42b of the movable scroll 42 is located in the spiral space. Be placed.

  Under this arrangement, the spiral walls 42b and 44b are in sliding contact with each other locally, and the tip surfaces of the spiral walls 42b and 44b are in sliding contact with the substrates 42a and 44a of the other scrolls 42 and 44, respectively. Therefore, by this arrangement, a compression chamber 60 is formed between the spiral walls 42b and 44b (see FIG. 2), and the volume and position of the compression chamber 60 change with the orbiting movement of the movable scroll 42. Through the process, the refrigerant suction, compression and discharge steps are executed.

Note that the outer end of the spiral space has a semi-cylindrical shape having a slightly larger curvature radius than the turning radius R of the movable scroll 42 so as to allow the outer end of the spiral wall 42b of the movable scroll 42 to turn.
An axial groove 62 is formed on the outer peripheral surface of the thick portion 44d of the fixed scroll 44, and the axial groove 62 extends in the axial direction of the fixed substrate 44a from the fixed substrate 44a to the tip surface of the spiral wall 44b.

  Further, a straight vane groove 64 is formed in the thick portion 44d, and the inner end of the vane groove 64 is located in the vicinity of the outer end of the spiral space. The outer end of the vane groove 64 opens to the outer peripheral surface of the thick portion 44d, that is, the inner peripheral wall 44c, and the side end thereof opens to the distal end surface of the thick portion 44d. The opening end of the vane groove 64 opened in the inner peripheral wall 44c is located in the vicinity of the axial groove 62 when viewed in the circumferential direction of the inner peripheral wall 44c, and immediately after the axial groove 62 when viewed in the turning direction of the movable scroll 42. positioned.

  A movable vane 66 having a flat shape as shown in FIG. 5 is disposed in the vane groove 64 so as to protrude toward the outer peripheral wall 42c. The movable vane 66 has a length, a width and a height of the vane groove 64. Each have substantially the same length, thickness and height. Therefore, both side surfaces of the movable vane 66 positioned on both sides in the thickness direction are in sliding contact with both side surfaces of the vane groove 64, and both end surfaces of the movable vane 66 positioned on both sides in the height direction are in sliding contact with the fixed substrate 44a or the movable substrate 42a. .

  The distal end surface of the movable vane 66 is rounded, and the curvature of the distal end surface matches the curvature of the inner peripheral wall 44c. When the sliding contact position between the inner peripheral wall 44c and the outer peripheral wall 42c matches the outer end position of the vane groove 64, the movable vane 66 is positioned at the rest position. When the movable vane 66 is in the rest position, the distal end surface of the movable vane 66 is positioned at the opening end of the vane groove 64 opened in the inner peripheral wall 44c and closes the opening end.

  Further, when the movable vane 66 protrudes from the opening end of the vane groove 64 toward the outer peripheral wall 42c and a part of the front end surface of the movable vane 66 is in sliding contact with the outer peripheral wall 42c, that is, the movable vane 66 is in the operating position. At this time, the crescent-shaped space between the inner peripheral wall 44 c and the outer peripheral wall 42 c is divided in the circumferential direction by the movable vane 66. In other words, the crescent-shaped space is divided into a front region located in front of the movable vane 66 and a rear region located in the rear as viewed in the turning direction of the movable scroll 42.

Each of the front region and the rear region of the crescent-shaped space forms an expansion chamber 68, and the volume and position of these expansion chambers 68 are changed with respect to the movable vane 66 by the orbiting movement of the movable scroll 42. It changes by moving relatively. Through this changing process, the expansion chamber 68 performs a refrigerant introduction, expansion and discharge process.
In the fluid machine 4, a suction chamber 70 and a discharge chamber 72 are formed between the above-described compression unit 40 and the end wall 18 b of the compression casing 18.

More specifically, a cylindrical portion 74 protruding in the axial direction from the outer peripheral edge thereof is integrally formed on the back surface of the fixed substrate 44 a, and the tip of the cylindrical portion 74 is formed on the inner peripheral surface of the peripheral wall 18 a of the compression casing 18. The annular step surface is in airtight contact (see FIG. 2).
Further, on the back surface of the fixed substrate 44a and on the end wall 18b of the compression casing 18, protrusions 76a and 76b projecting to the other side are formed, respectively, and the protrusions 76a and 76b protrude with their ends being airtight. The partition wall 76 is formed by being put together. The partition wall 76 avoids the central portion of the fixed substrate 44 a and crosses the back surface thereof, and partitions the space between the fixed substrate 44 a and the end wall 18 b into the suction chamber 70 and the discharge chamber 72.

A radial hole 74 a is formed in a portion of the cylindrical portion 74 surrounding the suction chamber 70, and the suction chamber 70 is connected to the inside of the drive casing 16 through the radial hole 74 a.
As shown in FIG. 6, the fixed scroll 44 has a discharge hole 78 that penetrates substantially the center of the fixed substrate 44 a and allows the compression chamber 60 and the discharge chamber 72 to communicate with each other. Opened and closed. The discharge valve 80 is composed of a reed valve body (not shown) and a stopper plate 82 that regulates the opening degree of the reed valve body. Both the reed valve body and the stopper plate 82 are attached to the fixed substrate 44a via a mounting screw 84. It has been.

Further, the fixed scroll 44 has a suction hole 86 that penetrates the fixed substrate 44a and allows the suction chamber 70 and the compression chamber 60 to communicate with each other. The suction hole 86 opens in front of the fixed substrate 44a in the vicinity of the outer end of the spiral space defined between the spiral walls 44b (see FIG. 4).
As shown in FIG. 7, a block 88 is integrally provided in the vicinity of the end wall 18b outside the peripheral wall 18a of the compression casing 18, and the compression casing 18 penetrates the block 88 and the peripheral wall 18a. A suction port 90 and a discharge port 92 are formed. The suction port 90 has an inner end that opens into the suction chamber 70, and an outer end that is connected to the return path of the circulation channel 2. The discharge port 92 has an inner end that opens to the discharge chamber 72, and an outer end that is connected to the forward path of the circulation channel 2.

  The fluid machine 4 includes a refrigerant supply / discharge path for the expansion device 41. In the fluid machine 4, the refrigerant supply / discharge path for the expansion device 41 and the expansion device 41 is connected from the discharge chamber 72 to the suction chamber 70. It also serves as a refrigerant recirculation path 94 extending over (see FIG. 1). The fluid machine 4 includes a capacity control valve 96 that can open and close the reflux path 94, and the reflux path 94 and the capacity control valve 96 can change the amount of refrigerant sent from the discharge port 92 to the circulation channel 2. Means.

More specifically, as the casing of the capacity control valve 96, a bulging portion 98 is integrally formed on the end wall 18b of the compression casing 18, and the bulging portion 98 has a columnar shape parallel to the end wall 18b (FIGS. 2 and 2). 7). The bulging portion 98 extends over both sides of the ridge 76 b, and one end of the bulging portion 98 is connected to the block 88 via the peripheral wall 18 a of the compression casing 18.
The series of blocks 88, the peripheral wall 18 a, and the bulging portion 98 are formed with a cylindrical hole 100 having an open end opened on the outer surface of the block 88, and the inner end surface of the hole 100 is in addition to the bulging portion 98. Located near the edge. The opening end of the hole 100 on the block 88 side is hermetically closed by the press-fitted plug 102, and the inner end wall of the plug 102 divides the valve chamber 104 between the inner end surface of the hole 100.

An inlet hole 106 that connects the valve chamber 104 and the discharge chamber 72 is formed in the bulging portion 98 as an input port of the capacity control valve 96, and the inlet hole 106 is an opening that opens to the inner peripheral surface of the valve chamber 104. Has an edge. A piston 108 as a valve body is disposed in the valve chamber 104 so as to reciprocate between a closed position and an open position, and the piston 108 has an outer peripheral surface that is in sliding contact with the inner peripheral surface of the valve chamber 104.
When the piston 108 is in a closed position separated from the plug 102, the open end of the inlet hole 106 is blocked by the outer peripheral surface of the piston 108. On the other hand, when the piston 108 is in the open position in contact with the plug 102, the opening end of the inlet hole 106 is opened, and the discharge chamber 72 and the valve chamber 104 communicate with each other through the inlet hole 106.

In order to apply a driving force for reciprocating movement to the piston 108, the region of the valve chamber 104 on the plug 102 side is passed through an orifice filter 112 fixed to a through hole 110 connecting the discharge chamber 72 and the hole 100. It always communicates with the discharge chamber 72.
The orifice filter 112 includes an orifice tube having an extremely fine internal flow path and a resin filter member surrounding one end of the orifice tube. The filter member protrudes into the discharge chamber 72, and the pressure in the discharge chamber 72 is transmitted to the region of the valve chamber 104 on the plug 102 side through the internal flow path of the orifice tube in a state where dust and the like are removed by the filter member.

  A compression coil spring 114 serving as a valve spring is disposed between the piston 108 and the inner end surface of the hole 100, and the compression coil spring 114 urges the piston 108 toward the plug 102. As shown in FIGS. 8 and 9, the piston 108 has hollow portions opened at both end faces, and the end of the hollow portion on the plug 102 side is a normally closed ball valve incorporated in the piston 108. It is opened and closed by 116.

When the ball valve 116 is closed, the pressure in the discharge chamber 72 is applied to the end face of the piston 108 on the plug 102 side through the orifice filter 112, and the piston 108 overcomes the urging force of the compression coil spring 114 from the plug 102. Positioned in a spaced apart closed position.
On the other hand, the ball valve 116 opens when the pressure in the suction chamber 70, that is, the pressure in the hollow portion becomes lower than a predetermined value. When the ball valve 116 is open, the pressure in the valve chamber 104 passes through the hollow portion on both sides of the piston 108. The piston 108 is moved from the closed position to the open position by the urging force of the compression coil spring 114. When the piston 108 is in the open position, the opening end of the inlet hole 106 is opened, whereby the discharge chamber 72 and the valve chamber 104 communicate with each other through the inlet hole 106.

The ball valve 116 opens once and then closes when the pressure in the hollow portion of the piston 108 increases. When the ball valve 116 is closed and the pressure difference between the valve chambers 104 on both sides of the piston 108 overcomes the biasing force of the compression coil spring 114, the piston 108 moves from the open position and is positioned at the closed position.
More specifically, the ball valve 116 has a bellows 118 disposed in the hollow portion of the piston 108, and one end of the bellows 118 is fixed in the hollow portion. A compression coil spring is accommodated in the bellows 118, and the bellows 118 can extend in the axial direction of the piston 108 when the biasing force of the compression coil spring overcomes the pressure of the hollow portion.

  A ball as a valve body is attached to the other end of the bellows 118, and the ball is located in the end of the hollow portion on the plug 102 side. A spherical seat is formed at the end of the hollow portion of the piston 108 so as to protrude radially inward from the inner peripheral surface, and the ball closes the hollow portion by sitting on the spherical seat from the outside. When the pressure in the hollow portion of the piston 108 falls below a predetermined pressure and the bellows 118 extends, a lift amount corresponding to the extension amount is applied to the ball, and the ball valve 116 is thereby opened.

In the vicinity of the other end of the bulging portion 98, an outlet hole 120 having one end opened in the end wall of the valve chamber 104 is formed as an output port of the capacity control valve 96. The outlet hole 120 is connected to a communication hole 122 formed in the fixed substrate 44a, and the communication hole 122 opens near the inner end of the vane groove 64 on the front surface of the fixed substrate 44a (see FIG. 2).
Here, as shown in FIGS. 4 and 5, the movable vane 66 described above has a stepped surface 124 extending in the height direction on one side surface located in front of the movable scroll 42 in the turning direction. A rear end portion on the rear end side with respect to the step surface 124 is formed thin. Accordingly, there is a space between the inner end of the vane groove 64 and the stepped surface 124 of the movable vane 66 even when the movable vane 66 is positioned at the rest position, even if the movable vane 66 is at the rest position. When a refrigerant having a pressure higher than that in the crescent-shaped space flows into this space, the movable vane 66 is biased toward the outer peripheral wall 42c by the pressure of the refrigerant applied to the step surface 124. That is, the step surface 124 functions as a pressure receiving surface for the refrigerant pressure.

  Further, the movable vane 66 is formed with a notch 126 at a tip portion on the tip side of the step surface 124. The notch 126 opens on the other side surface of the movable vane 66 and is slidably contacted with the movable substrate 42a. An opening is also formed on the side end surface of the vane 66. Although the opening of the cutout 126 on the movable substrate 42a partly coincides with the pocket 58 of the movable scroll 42 as the movable scroll 42 turns, the void near the inner end of the vane groove 64 is also movable. It can be periodically and partially matched to the pocket 58 of the scroll 42. That is, the pocket 58 of the movable scroll 42 crosses the void near the inner end of the vane groove 64 and the notch 126 simultaneously and intermittently with the turning motion of the movable scroll 42. The space near the inner end and the notch 126 communicate periodically.

  At the time of this communication, if the notch 126 protrudes from the vane groove 64 and opens to the rear region of the crescent-shaped space, that is, the expansion chamber 68, the space between the communication hole 122 and the expansion chamber 68 is the inner end of the vane groove 64. It communicates through a nearby space, the notch 126 of the movable vane 66 and the pocket 58 of the movable scroll 42. That is, these voids, the notch 126 and the pocket 58 together with the inlet hole 106, the valve chamber 104, the outlet hole 120 and the communication hole 122 of the capacity control valve 96, the refrigerant supply path from the discharge chamber 72 to the expansion chamber 68. Is forming.

The fixed substrate 44 a is formed with a discharge hole 128 that communicates between the axial groove 62 and the suction chamber 70. The axial groove 62 and the discharge hole 128 serve to transfer the refrigerant from the expansion chamber 68 to the suction chamber 70. A discharge route is formed.
Hereinafter, the operation of the fluid machine 4 described above will be described.
When the fluid machine 4 is supplied with power from the engine 38 and the movable scroll 42 is swung with respect to the fixed scroll 44, the compression chamber 60 increases and decreases in volume and the discharge hole 78 as shown in FIG. Thus, a series of processes of suction, compression, and discharge are performed on the low-temperature and low-pressure gaseous refrigerant sucked into the suction chamber 70 from the return path of the circulation flow path 2. The high-temperature and high-pressure gaseous refrigerant discharged from the compression chamber 60 to the discharge chamber 72 through this process is sent to the forward path of the circulation flow path 2, whereby the refrigerant circulates in the circulation flow path 2.

  As shown in FIG. 1, the high-temperature and high-pressure gaseous refrigerant is cooled by air in the condenser 6 and condensed, and then the gas phase components and moisture are removed by the receiver 8 to become a low-temperature and high-pressure liquid refrigerant. Thereafter, the liquid refrigerant becomes a low-temperature and low-pressure wet refrigerant through the expansion valve 10, and the wet refrigerant evaporates in the evaporator 12 to become a low-temperature and low-pressure gaseous refrigerant. Here, if a fan (not shown) generates a wind from the evaporator 12 toward the vehicle interior, the cool air deprived of vaporization heat by the evaporator 12 is supplied to the vehicle interior, thereby adjusting the temperature in the vehicle interior. The

The low-temperature and low-pressure gaseous refrigerant in the evaporator 12 is sucked into the fluid machine 4 through the return path of the circulation flow path 2, and the above-described refrigeration cycle is repeated.
The fluid machine 4 includes a variable capacity means for adjusting the circulating flow rate of the refrigerant. The variable capacity means operates as follows.
When the rotational speed of the engine 38 increases and the flow rate of the refrigerant sent from the discharge port 92 of the fluid machine 4 to the forward path of the circulation flow path 2 increases, the refrigerant pressure (low pressure) in the evaporator 12 decreases. When the refrigerant pressure in the hollow portion of the suction chamber 70 and the piston 108 falls below a predetermined value due to the lowering of the low pressure, the ball valve 116 built in the capacity control valve 96 is opened by the extension of the bellows 118, and the piston 108 is closed. Move from position to open position.

  While the piston 108 is in the open position, a part of the high-temperature and high-pressure gaseous refrigerant in the discharge chamber 72 is near the inner end of the vane groove 64 through the inlet hole 106, the valve chamber 104, the outlet hole 120, and the communication hole 122. Supplied to the void. The refrigerant pressure in the void is applied to the step surface 124 of the movable vane 66, and the movable vane 66 is moved from the rest position to the operating position based on the pressure difference between the pressure applied to the step surface 124 and the pressure applied to the tip surface of the movable vane 66. It is energized towards.

  If the outer peripheral wall 42c is separated from the opening end of the vane groove 64 opened in the inner peripheral wall 44c in a state where the movable vane 66 is biased, the movable vane 66 protrudes toward the outer peripheral wall 42c, and the front end surface of the movable vane 66 A part of the slidably contacts the outer peripheral wall 42c (FIG. 10 (1)). That is, at the same time that the movable vane 66 protrudes from the vane groove 64, an expansion chamber 68 is formed behind the movable vane 66 when viewed in the turning direction of the movable scroll 42.

  Although the volume of the expansion chamber 68 increases and decreases with the turning motion of the movable scroll 42, that is, the outer peripheral wall 42c and approaches the axial groove 62, the vane is in the initial stage of the volume increase process of the expansion chamber 68. The space in the vicinity of the inner end of the groove 64 and the expansion chamber 68 communicate with each other through the pocket 58 and the cutout portion 126 of the movable vane 66, whereby the refrigerant in the space is introduced into the expansion chamber 68 (FIG. 10 (1)). ) To (3)).

The refrigerant introduced into the expansion chamber 68 expands from the middle stage to the latter stage of the volume increasing process of the expansion chamber 68 (FIGS. 10 (4) to (7)). In the decreasing process, the gas is discharged to the suction chamber 70 through the axial groove 62 and the discharge hole 128 communicating with the expansion chamber 68 (FIGS. 10 (8) to (7)).
Therefore, according to this capacity varying means, a part of the refrigerant in the discharge chamber 72 is recirculated to the suction chamber 70 through the expansion chamber 68, and thus the flow rate of the refrigerant sent to the outgoing path of the circulation flow path 2 is reduced. At this time, the gaseous refrigerant which has expanded in the expansion chamber 68 to a low temperature and low pressure is recirculated to the suction chamber 70.

  On the other hand, when the rotation speed of the engine 38 is low and the pressure in the hollow portion of the piston 108 is higher than a predetermined value, the capacity control valve 96 is closed, so that a void near the inner end of the vane groove 64 and a crescent shape are formed. There is no difference in pressure between the two spaces, and the urging force does not act on the movable vane 66. Accordingly, in this case, as shown in FIGS. 11 (1) to (8), the crescent-shaped space is not partitioned in the circumferential direction by the movable vane 66, and the inner peripheral wall 44c is accompanied by the turning motion of the movable scroll 42. Move around. That is, the expansion chamber 68 is not formed while the supply path of the working fluid to the expansion chamber 68 is closed.

In order to explain the relative positional relationship between the pocket 58 of the movable substrate 42a, the space near the inner end of the vane groove 64, and the notch 126 of the movable vane 66, the movable substrate 42a in FIGS. The pocket 58 is indicated by a solid line.
According to the fluid machine 4 described above, the expansion chamber 68 is formed outside the scroll-type compression unit 40 having the compression chamber 60 with a simple configuration using the inner peripheral wall 44c, the outer peripheral wall 42c, and the movable vane 66. . Therefore, this fluid machine 4 is suitable for downsizing.

  In the fluid machine 4, the volume of the expansion chamber 68 increases or decreases with the relative turning motion of the inner peripheral wall 44 c and the outer peripheral wall 42 c, that is, in conjunction with the operation of the compression unit 40. The refrigerant is introduced at the beginning of the volume increasing process. The high-pressure refrigerant introduced into the expansion chamber 68 gives a turning force to the outer peripheral wall 42c in the direction of increasing the volume of the expansion chamber 68 from the middle to the end of the volume increasing process.

  Since the direction of this turning force is the same as the turning direction of the movable scroll 42, it becomes auxiliary power for operating the movable scroll 42, that is, the compression unit 40. Therefore, if the refrigerant is expanded in the expansion chamber 68 to increase the volume of the expansion chamber 68, the compression unit 40 can obtain auxiliary power from the expansion device 41, and the power supplied from the engine 38 can be reduced. In other words, the load on the engine 38 can be reduced.

  Further, in this fluid machine 4, the refrigerant recirculated by the capacity varying means expands in the expansion chamber 68 and becomes a low temperature, so that the temperature of the refrigerant supplied to the compression chamber 60 is prevented from rising, and the compression chamber 60 Is cooled by the outer expansion chamber 68. Therefore, even if the refrigerant recirculation amount is large, the compression chamber 60 is not overheated, and the capacity variable means can recirculate a larger amount of working fluid, and the variable range is widened. Further, since the overheating of the compression chamber 60 is prevented, the durability of the fluid machine 4 is not lowered.

Further, according to the fluid machine 4, the inner peripheral wall 44c of the expansion device 41 is cooled by the expanded low-temperature refrigerant, so that the spiral wall 44b of the fixed scroll 44 of the compression unit 40 integrated with the inner peripheral wall 44c is formed. Since it cools efficiently, overheating of the compression chamber 60 is prevented more reliably.
In the fluid machine 4, since the capacity control valve 96 is provided in the refrigerant supply path to the expansion chamber 68, the supply of the refrigerant to the expansion chamber 68 is shut off when the capacity control valve 96 is closed, and the expansion is performed. The pressure of the refrigerant in the chamber 68 becomes equal to the pressure of the refrigerant in the suction chamber 70 through the axial groove 62 and the discharge hole 128. Therefore, according to the fluid machine 4, when the capacity control valve 96 is closed, the high-pressure refrigerant does not stay in the expansion chamber 68, and the refrigerant in the expansion chamber 68 serves as a load to operate the compression unit 40. Is prevented from being disturbed.

  The present invention is not limited to the above-described embodiment, and various modifications are possible. For example, in the case of the embodiment, the inner peripheral wall 44c of the expansion device 41 is integrated with the spiral wall 44b of the fixed scroll 44. Although provided, the inner peripheral wall 44c only needs to surround the spiral wall 44b, and may be separate from the spiral wall 44b. However, if the inner peripheral wall 44c is provided integrally with the spiral wall 44b of the fixed scroll 44 as in the fluid machine 4, the inner peripheral wall 44c is cooled by the expanded low-temperature refrigerant. Since the spiral wall 44b that is integrated with the cooling chamber 44 is efficiently cooled, overheating of the compression chamber 60 is more reliably prevented.

  In one embodiment, the inner peripheral wall 44c of the expansion device 41 is provided integrally with the spiral wall 44b of the fixed scroll 44, and the outer peripheral wall 42c is provided integrally with the substrate 42a of the movable scroll 42. The outer peripheral wall may be provided integrally with the fixed substrate 44a. Further, the inner peripheral wall may be provided integrally with the movable substrate 42 a and the outer peripheral wall may be provided integrally with the peripheral wall 18 a of the compression casing 18.

  In one embodiment, the movable vane 66 is disposed so as to be able to protrude from the inner peripheral wall 44c toward the outer peripheral wall 42c. However, the movable vane is disposed so as to be able to protrude from the outer peripheral wall 42c toward the inner peripheral wall 44c. May be. However, in order to do so, it is necessary to form the vane groove on the outer peripheral wall 42c, leading to an increase in the size of the fluid machine. Thus, like the fluid machine 4, the vane groove 64 is formed in the inner peripheral wall 44c, and The movable vane 66 is preferably disposed so as to protrude from the inner peripheral wall 44c toward the outer peripheral wall 42c.

  In one embodiment, as an urging means for projecting the movable vane 66 from the vane groove 64, the communication hole 122 opens near the inner end of the vane groove 64, and a high pressure is formed in a space near the inner end of the vane groove 64. However, a compression coil spring that urges the movable vane 66 in the protruding direction may be disposed between the inner end of the vane groove 64 and the rear end of the movable vane 66. However, if the movable vane 66 is energized by the pressure difference between the expansion chamber 68 and the space near the inner end of the vane groove 64, that is, the supply path, the number of parts is reduced because a compression coil spring is not required. Therefore, productivity improvement and price reduction of the fluid machine 4 can be achieved.

In one embodiment, the ratio of the capacity of the expansion chamber 68 to the capacity of the compression chamber 60 can be easily changed by adjusting the ratio of the height of the inner peripheral wall 44c and the outer peripheral wall 42c to the height of the spiral walls 42b, 44b. Is possible.
In one embodiment, the opening end of the communication hole 122 is opened in the vane groove 64, and the expansion chamber 68 is formed by a space near the inner end of the vane groove 64, the pocket 58 of the movable substrate 42 a and the notch 126 of the movable vane 66. By forming a part of the supply path of the refrigerant with respect to the space and utilizing the swiveling movement of the pocket 58 with respect to the void and the notch 126, the supply path is opened in synchronization with the initial stage of the volume increasing process of the expansion chamber 68. However, the means for synchronously opening and closing the supply path is not limited, and an encoder and an electromagnetic control valve may be used in combination. In this case, the communication hole may be directly opened in the expansion chamber 68.

  However, if the supply path synchronous opening / closing means is constituted by the pocket 58 of the movable substrate 42a and the cutout portion 126 of the movable vane 66 as in one embodiment, it is easy to synchronize the opening / closing timing to the initial stage of the volume increasing process. In addition, since a separate member is not required, the number of parts can be reduced, thereby improving the productivity of the fluid machine 4 and reducing the price. Further, by changing the shape, size, position, and the like of the pocket 58, the rear end of the movable vane 66, and the notch 126, the introduction start timing and the introduction end timing of the refrigerant into the expansion chamber 68 can be easily adjusted. Therefore, the expansion rate in the expansion chamber 68 can be changed.

FIG. 12 shows a movable vane 130 according to a modified example. The movable vane 130 extends in the height direction of the movable vane 130 instead of the notch 126, and has a bottom with an opening at a side end surface that is in sliding contact with the movable substrate 42a. It has a hole 132 and a lateral hole 134 extending in the length direction of the movable vane 130 between the bottomed hole 132 and the stepped surface 124.
FIG. 13 is a view for explaining the operation of the fluid machine 4 to which the modified circular pocket 136 is applied together with the movable vane 130. In the case of the embodiment, the space near the inner end of the vane groove 64 and the notch 126 of the movable vane 66 are periodically communicated by the pocket 58 of the movable substrate 42a. The opening end of the bottomed hole 132 of the vane 130 and the expansion chamber 68 communicate with each other through the pocket 136. In FIG. 13, the pocket 136 of the movable substrate 42a is shown by a solid line in order to explain the relative positional relationship between the pocket 136 of the movable substrate 42a and the open end of the bottomed hole 132 of the movable vane 66.

In the case of one embodiment, the expansion device 41 and the refrigerant supply / discharge path to the expansion device 41 constitute the reflux path 94 of the fluid machine 4, but the expansion device 41 and the supply / discharge thereof as in the reference example shown in FIG. separating the path from the return path 94, it is also possible to use an expansion device 41 in place of the bulging expansion valve 10. For this purpose, the compression casing 18 may be provided with an introduction port and a discharge port for directly connecting the supply / discharge path of the expansion device 41 and the circulation flow path 2. In this case, the pressure energy of the refrigerant is used as auxiliary power for the compression unit 40 via the expansion device 41, so that power consumption of the fluid machine 4 can be reduced. In this case, the fluid machine 4 may be provided with a capacity varying means separately from the expansion device 41.

When the compression casing 18 is provided with an introduction port and a discharge port for the expansion device 41, the expansion device 41 of the fluid machine 4 is replaced with a waste heat recovery cycle of the cooling system of the engine 38 as in the reference example shown in FIG. You may apply to. This waste heat recovery cycle (Rankine cycle) can be installed in the vehicle together with the refrigeration cycle.
The waste heat recovery cycle has a cooling water circulation passage 138 through which the circulating cooling water recirculates, and the cooling water circulation passage 138 is inserted with a cooling water pump 140, an engine 38, an expansion device 41, and a radiator 142 sequentially. The cooling water pump 140 sucks and compresses cooling water in a low-temperature and low-pressure liquid state from the return path of the cooling water circulation channel 138, and sends the cooling water in a low-temperature and high-pressure liquid state to the forward path. The cooling water delivered from the cooling water pump 140 is heated by the engine 38 to be in a high-temperature and high-pressure gas state, and then expanded in the expansion device 41 to be in a low-temperature and low-pressure gas state. To condense. The condensed cooling water is sucked into the cooling water pump 140, and the above-described cycle is repeated. In this case, the heat energy of the waste heat generated in the engine 38 is used as auxiliary power for the compression unit 40 via the expansion device 41, so that power consumption of the fluid machine 4 can be reduced.

  Finally, it goes without saying that the fluid machine of the present invention can be applied to various working fluids such as water and refrigerant.

It is a figure which shows the outline of the refrigerating cycle of the vehicle air conditioning system to which the fluid machine of one Example is applied. It is a longitudinal cross-sectional view of the fluid machine of one Example. It is a front view of the movable scroll of the fluid machine of FIG. It is a front view which shows the fixed scroll of the fluid machine of FIG. 2 with a movable vane. It is a perspective view of the movable vane of the fluid machine of FIG. It is a rear view which shows the fixed scroll of FIG. 4 with a discharge valve. FIG. 3 is a transverse sectional view of the fluid machine taken along line VII-VII in FIG. 2. It is the figure which showed a part of refrigeration cycle of FIG. 1 with the longitudinal cross-section of the capacity | capacitance control valve of the fluid machine of a closed state. It is the figure which showed a part of refrigeration cycle of FIG. 1 with the longitudinal cross-section of the capacity | capacitance control valve of the fluid machine of an open state. It is a figure for demonstrating operation | movement of a compression unit and an expansion apparatus when a capacity | capacitance control valve is in an open state. It is a figure for demonstrating operation | movement of a compression unit and an expansion apparatus when a capacity | capacitance control valve exists in a closed state. It is a perspective view of the movable vane of a modification. It is a figure for demonstrating operation | movement of the compression unit and expansion apparatus in the fluid machine to which the movable vane and pocket of a modification are applied. It is a figure which shows the outline of the refrigerating cycle of the vehicle air conditioning system to which the fluid machine which is a reference example is applied. It is a figure which shows the outline of the refrigerating cycle of the vehicle air conditioning system which applied the fluid machine which is a reference example, and the waste heat recovery cycle of an engine cooling system.

Explanation of symbols

4 Fluid Machine 14 Housing 40 Compression Unit 41 Expansion Device 58 Pocket 42 Movable Scroll 42a Movable Scroll Substrate 42b Movable Scroll Spiral Wall 42c Peripheral Wall 44 Fixed Scroll 44a Fixed Scroll Substrate 44b Fixed Scroll Spiral Wall 44c Inner Perimeter Wall 58 Pocket ( Supply route)
60 Compression chamber 64 Vane groove 66 Vane 68 Expansion chamber 104 Valve chamber (supply path)
106 Inlet hole (supply path)
120 outlet hole (supply path)
122 communication hole (supply route)
126 Notch (supply path)

Claims (6)

A housing;
A scroll-type compression unit provided in the housing, having a fixed and movable spiral wall which cooperates with each other to form a compression chamber, and provided with a suction hole communicating with the compression chamber on an end surface of the unit;
An expansion device provided between the housing and the compression unit ;
A working fluid supply path and a discharge path for the expansion device;
The inflator is
An inner peripheral wall surrounding the outside of the compression unit;
An outer peripheral wall provided around the inner peripheral wall and pivoting relative to the inner peripheral wall in conjunction with the operation of the compression unit;
A movable vane capable of partitioning a space between the outer peripheral wall and the inner peripheral wall in the circumferential direction and forming an expansion chamber whose volume increases or decreases with the relative swirl movement between the peripheral walls;
Synchronous opening and closing means for opening and closing the supply path in synchronization with the volume increase and decrease of the expansion chamber formed by the movable vane ;
A working fluid recirculation path extending from the discharge hole of the compression chamber to the suction hole, and a capacity control valve capable of opening and closing the recirculation path, and a part of the working fluid discharged from the discharge hole to the recirculation path Through the capacity variable means that can be recirculated to the suction hole through,
The fluid machine , wherein the expansion chamber forms the reflux path together with the supply path and the discharge path . The fluid machine according to claim 1, wherein the inner peripheral wall is provided integrally with one of the spiral walls. The displacement control valve includes a fluid machine according to claim 1 or 2, characterized in that provided in the supply path. The expansion device according to claim 1 to 3, characterized in that further comprising a biasing means for biasing the movable vanes in the protruding direction on the basis of the pressure difference between the supply path and the expansion chamber The fluid machine according to any one of the above. The movable vane has an end surface that is slidably contacted with an end wall of the expansion chamber in association with the relative swiveling motion,
The supply path is
A recess provided in the end face of the movable vane;
A pocket formed in the end wall of the expansion chamber,
The said pocket is formed in the area | region of the said end wall which crosses the said dent of the said movable vane intermittently with the said relative turning motion so that the said synchronous opening / closing means may be comprised. 5. The fluid machine according to any one of 4 . The inner wall and the outer peripheral wall, the fluid machine according to any one of claims 1 to 5, characterized in that has a height different from the height of the spiral wall.

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