JP2015063895A - Pulsation pressure reducing device in refrigeration cycle - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a pulsation pressure reducing device in a refrigeration cycle capable of being applied to a refrigerant passage included by a compressor and refrigerant piping of an external refrigerant circuit connected to the refrigerant passage, in addition to being capable of reducing pulsation pressure of the refrigerant passage.SOLUTION: In a pulsation pressure reducing device in a refrigeration cycle for circulating a refrigerant in a refrigerant passage, a flow divider 60 is provided for dividing the flow of the refrigerant and passing it in the refrigerant passage. The flow divider 60 has a flow dividing plate 62 for dividing the refrigerant passage into a first flow passage F1 and a second flow passage F2 from an inlet formed on an upstream side to an outlet formed on a downstream side. By the flow dividing plate 62, a flow passage cross sectional area of the first flow passage F1 increases from the inlet toward the outlet, and a flow passage cross sectional area of the second flow passage F2 decreases from the inlet toward the outlet. The flow passage cross sectional area of the outlet of the second flow passage F2 is set to be smaller than the flow passage cross sectional area of the outlet of the first flow passage F1.

Description

  The present invention relates to a pulsation pressure reducing device in a refrigeration cycle, and more particularly to a pulsation pressure reducing device in a refrigeration cycle provided with a flow divider for diverting and passing a refrigerant flowing through a refrigerant flow path.

As a conventional technique related to a pulsation pressure reducing device in a refrigeration cycle, for example, a compressor having a pulsation pressure reducing structure disclosed in Patent Document 1 is known.
In the compressor disclosed in Patent Document 1, the discharge chamber and the discharge pipe line are communicated with each other via two discharge ports spaced apart from each other.
The refrigerant flow discharged from the two discharge ports has a phase difference in pulsation pressure, and the pulsation pressure in which the phase difference has occurred is dispersed and discharged into the discharge pipe to suppress an increase in the refrigerant discharge pulsation pressure. Yes.

As another related art, for example, a hermetic compressor disclosed in Patent Document 2 can be cited.
In the hermetic compressor disclosed in Patent Document 2, three connection pipe passages having different lengths and different cross-sectional areas are provided upstream of the suction hole.
In this hermetic compressor, since the connecting pipe passage does not always have a constant natural frequency mode, the generation of noise caused by abnormal vibration of the refrigerant gas and a sudden deterioration in performance are prevented.

Japanese Patent Laid-Open No. 2003-13848 JP-A-4-191479

However, in the compressor disclosed in Patent Document 1, since the discharge chamber and the discharge pipe are communicated with each other via two discharge ports spaced apart from each other, the shape of the compressor housing becomes a special shape. There is a problem.
Further, in the compressor disclosed in Patent Document 1, the configuration for reducing the pulsation pressure can be applied only to the refrigerant flow path in the compressor, and cannot be applied to the refrigerant piping of the external refrigerant circuit.
On the other hand, since the compressor disclosed in Patent Document 2 is a connecting pipe passage having three different lengths and different cross-sectional areas, it cannot be applied to the refrigerant flow path of the compressor with limited space. .
Further, since the piping of the connecting pipe passage itself has a special structure, there is a problem that the manufacturing cost is increased and the assembling work takes time.

  The present invention has been made in view of the above problems, and an object of the present invention is to reduce the pulsation pressure of the refrigerant flow path, as well as the refrigerant passage provided in the compressor and the refrigerant of the external refrigerant circuit connected to the refrigerant passage. It is in providing the pulsation pressure reduction apparatus in the refrigerating cycle applicable to piping.

  In order to solve the above-mentioned problems, the present invention is a pulsation pressure reducing device in a refrigeration cycle in which a refrigerant is circulated in a refrigerant flow path, and is provided with a flow divider that divides and passes the refrigerant in the refrigerant flow path. The flow divider includes a flow dividing plate that divides the refrigerant flow path into a first flow path and a second flow path from an inlet formed on the upstream side to an outlet formed on the downstream side. The channel cross-sectional area of the first channel increases from the inlet toward the outlet, the channel cross-sectional area of the second channel decreases from the inlet toward the outlet, and the second channel The channel cross-sectional area of the outlet of the first channel is set smaller than the channel cross-sectional area of the outlet of the first channel.

In the present invention, the refrigerant passing through the refrigerant flow path passes through the flow divider. However, in the flow divider, the refrigerant is divided into the refrigerant passing through the first flow path and the refrigerant passing through the second flow path.
The channel cross-sectional area of the first channel increases from the inlet to the outlet, the channel cross-sectional area of the second channel decreases from the inlet to the outlet, and the channel cross-sectional area of the outlet of the second channel is It is set smaller than the channel cross-sectional area at the outlet of the first channel.
For this reason, the speed and pressure of the refrigerant passing through the first flow path and the refrigerant passing through the second flow path are different from each other, and as a result, the pulsation pressure is reduced.
According to the present invention, it is possible to reduce the pulsation pressure in the refrigerant flow path simply by providing the flow divider in the refrigerant flow path.

In the pulsation pressure reducing device in the refrigeration cycle, the flow dividing plate may have a plurality of through holes that communicate the first flow path and the second flow path.
In this case, due to the pressure difference between the first flow path and the second flow path, a part of the refrigerant passing through the second flow path flows to the first flow path through the plurality of through holes.
At this time, when the refrigerant passes through the through hole, a vortex is generated in the vicinity of the through hole of the first flow path.
The generation of vortices consumes the fluid energy of the refrigerant, thereby helping to reduce the pulsating pressure.

Further, in the pulsation pressure reducing device in the refrigeration cycle, the flow divider is formed in a cylindrical shape, a part functions as the flow dividing plate, and the remaining part is formed as a wall body having an arcuate cross section. It is good also as a structure attached to the surrounding wall of a road.
In this case, if the flow divider is press-fitted into the refrigerant flow path, the flow divider is fitted into the refrigerant flow path by a wall having an arcuate cross section, so that the flow divider can be easily installed in the refrigerant flow path.

Further, in the pulsation pressure reducing device in the refrigeration cycle, the flow dividing plate may have an inlet side end portion in which a plate thickness is set smaller from the downstream side toward the upstream side.
In this case, since the resistance due to the flow dividing plate on the inlet side of the flow divider is reduced, the pressure loss of the refrigerant passing through the flow divider can be suppressed.

In the pulsation pressure reducing device in the refrigeration cycle, the refrigeration cycle may include a compressor, and the flow divider may be provided in a refrigerant flow path in the compressor.
In this case, since the flow divider is provided in the refrigerant flow path in the compressor, the pulsation pressure in the refrigerant flow path in the compressor can be reduced.

Further, in the pulsation pressure reducing device in the refrigerant flow path, the refrigerant flow path is formed in the housing of the compressor, and is a suction passage through which refrigerant before compression and a discharge passage through which compressed refrigerant passes, The flow divider may be provided in at least one of the suction passage and the discharge passage.
In this case, the pulsation pressure in at least one of the suction passage and the discharge passage can be reduced only by providing it in at least one of the suction passage and the discharge passage in the compressor.

In the pulsation pressure reducing device in the refrigerant flow path, the flow divider may be provided in a refrigerant pipe of the refrigeration cycle.
In this case, the pulsation pressure in the refrigerant pipe of the refrigeration cycle can be reduced only by providing the flow divider in the refrigerant pipe of the refrigeration cycle.

  According to the present invention, it is possible to provide a pulsation pressure reducing device in a refrigeration cycle that can be applied to a refrigerant passage of a compressor and a refrigerant pipe of an external refrigerant circuit connected to the refrigerant passage, in addition to being able to reduce the pulsation pressure of the refrigerant passage. Can do.

It is a longitudinal section showing an outline of a compressor concerning a 1st embodiment. (A) is an enlarged vertical sectional view showing an enlarged main part of the compressor, (b) is an AA arrow view in (a), (c) is an exploded view of the shunt and the connecting member It is a perspective view. It is explanatory drawing which shows typically the flow of the refrigerant | coolant in a shunt. It is a longitudinal cross-sectional view which expands and shows the principal part of the compressor which concerns on 2nd Embodiment. It is a longitudinal cross-sectional view which expands and shows the principal part of the external refrigerant | coolant piping which concerns on 3rd Embodiment. It is a longitudinal cross-sectional view which expands and shows the principal part of the external refrigerant | coolant piping which concerns on 4th Embodiment. (A) is an expanded longitudinal cross-sectional view which expands and shows the principal part of the compressor which concerns on 5th Embodiment, (b) is a perspective view of a shunt. (A) is a longitudinal sectional view showing a flow dividing plate according to another example 1, and (b) is a vertical sectional view showing a flow dividing plate according to another example 2.

(First embodiment)
Hereinafter, a pulsation pressure reducing device (hereinafter referred to as “pulsation pressure reducing device”) in the refrigeration cycle according to the first embodiment will be described with reference to the drawings.
The present embodiment is an example of a pulsation pressure reducing device in which a shunt is provided in a discharge passage of a variable displacement swash plate compressor (hereinafter referred to as “compressor”).

A compressor 10 shown in FIG. 1 is a compressor for vehicle air conditioning mounted on a vehicle.
In the compressor 10 shown in FIG. 1, a front housing 12 is joined to the front end of the cylinder block 11, and a rear housing 13 is joined to the rear end of the cylinder block 11.
The cylinder block 11, the front housing 12 and the rear housing 13 are connected to each other by a plurality of through bolts (only one is shown in FIG. 1) 14.
The cylinder block 11 is formed with bolt through holes (not shown) through which the through bolts 14 are inserted, and the front housing 12 is formed with bolt through holes 15.
A bolt hole (not shown) having a female screw is formed in the rear housing 13, and a male screw portion of a through bolt 14 is screwed into the bolt hole.
The cylinder block 11, the front housing 12 and the rear housing 13 are made of an aluminum-based metal material and constitute the entire housing of the compressor 10.

A control pressure chamber 16 is formed in the front housing 12 by joining the front housing 12 and the cylinder block 11.
A shaft hole 17 is formed in the cylinder block 11.
A drive shaft 18 is inserted through the shaft hole 17, and the drive shaft 18 is rotatably supported by the cylinder block 11 via a radial bearing 19.
A shaft hole 20 is formed in the front housing 12, and a drive shaft 18 is inserted through the shaft hole 20.
The drive shaft 18 is rotatably supported by the front housing 12 via a radial bearing 21.

A shaft sealing device 22 is provided in the shaft hole 20, and a lip seal mainly made of a rubber material is used for the shaft sealing device 22.
The shaft seal device 22 has a function of preventing leakage of refrigerant gas and lubricating oil from the shaft hole 20.
The drive shaft 18 is operatively connected to an engine 23 as an external drive source mounted on the vehicle, and receives a power transmission from the engine 23 to obtain a rotational drive force.
The compressor 10 of this embodiment employs a configuration in which the power of the engine 23 is always transmitted to the drive shaft 18 via a power transmission mechanism, and is a clutchless type compressor 10.
Although the clutchless type compressor 10 is used in the present embodiment, a compressor that receives power transmission from an external drive source via a clutch may be used.

A rotation support 24 is fixed to the drive shaft 18, and the rotation support 24 can rotate integrally with the drive shaft 18.
A thrust bearing 25 that receives a load in the axial direction of the drive shaft 18 is interposed between the rotary support 24 and the inner wall surface of the front housing 12.
The swash plate 26 is supported by the drive shaft 18 so as to be tiltable in the axial direction of the drive shaft 18 and to be slidable in the axial direction with respect to the drive shaft 18.
A hinge mechanism 27 is interposed between the rotary support 24 and the swash plate 26.
The hinge mechanism 27 allows the swash plate 26 to tilt with respect to the rotary support 24 and connects the drive shaft 18 to the swash plate 26 so that torque can be transmitted.

The cylinder block 11 is formed with a plurality of cylinder bores 28 (only one is shown in FIG. 1).
A single-headed piston 29 is accommodated in each cylinder bore 28 so as to be capable of reciprocating.
Each piston 29 is anchored to the outer periphery of the swash plate 26 via a shoe 30.
Between the cylinder block 11 and the rear housing 13, a suction valve forming plate 31, a valve plate 32, a discharge valve forming plate 33 and a retainer forming plate 34 are interposed.

A suction valve forming plate 31, a valve plate 32, a discharge valve forming plate 33 and a retainer forming plate 34 are interposed between the cylinder block 11 and the rear housing 13, so that a suction chamber 35 is provided inside the rear housing 13. The discharge chamber 36 is partitioned.
The suction chamber 35 is formed on the center side of the rear housing 13, and the discharge chamber 36 is formed around the suction chamber 35 in the rear housing 13.
As shown in FIG. 1, a partition wall 37 formed in the rear housing 13 separates the suction chamber 35 and the discharge chamber 36.

The valve plate 32 is formed with a suction port 38 that communicates the suction chamber 35 and the cylinder bore 28, and a discharge port 39 that communicates the discharge chamber 36 and the cylinder bore 28.
The suction port 38 and the discharge port 39 are respectively formed corresponding to the number of cylinder bores 28.
The suction valve forming plate 31 is formed with suction valves 40 that open and close the suction ports 38, and the suction valves 40 are formed corresponding to the number of suction ports 38.
The discharge valve forming plate 33 is formed with discharge valves 41 for opening and closing the discharge ports 39, and the discharge valves 41 are formed corresponding to the number of discharge ports 39.
The suction valve 40 and the discharge valve 41 are lead type on-off valves that can be bent by elastic deformation.
The retainer forming plate 34 includes a plurality of retainers 43 corresponding to the number of discharge valves 41.
The retainer 43 regulates the curvature of the discharge valve 41 and regulates the maximum opening degree of the discharge valve 41.

As shown in FIG. 1, the rear housing 13 is formed with a suction port 45 connected to the external refrigerant circuit 44, and the suction port 45 and the suction chamber 35 are communicated by a suction passage 46.
A discharge port 47 connected to the external refrigerant circuit 44 is formed in the rear housing 13, and the discharge port 47 and the discharge chamber 36 are communicated by a discharge passage 48.
In the present embodiment, the external refrigerant circuit 44 and the compressor 10 constitute a refrigerant flow path in the refrigeration cycle.
Therefore, the external refrigerant circuit 44 constitutes a part of the refrigerant flow path in the refrigerant cycle.
Further, the suction passage 46 and the discharge passage 48 of the compressor 10 constitute a part of the refrigerant flow path in the refrigerant cycle.

The pulsation pressure reducing device according to the present embodiment includes a compressor 10, an external refrigerant circuit 44 connected to the discharge port 47 and the suction port 45 of the compressor 10, and a shunt 60 described later.
For example, carbon dioxide or chlorofluorocarbon is used as the refrigerant.
The external refrigerant circuit 44 includes a condenser 51, a receiver tank 52, an expansion valve 53, and an evaporator 54 in order from the discharge port 47 side.

By the way, the cylinder block 11 is formed with an extraction passage 55 that allows the control pressure chamber 16 and the suction chamber 35 to communicate with each other.
The extraction passage 55 is a passage for discharging the refrigerant in the control pressure chamber 16 to the suction chamber 35.
An air supply passage 56 that communicates the discharge chamber 36 and the control pressure chamber 16 is formed across the cylinder block 11 and the rear housing 13.
The air supply passage 56 is a passage for supplying a part of the refrigerant in the discharge chamber 36 to the control pressure chamber 16.
In the rear housing 13, a capacity control valve 57 is disposed midway in the air supply passage 56.

By adjusting the opening of the capacity control valve 57, the amount of high-pressure refrigerant introduced into the control pressure chamber 16 via the air supply passage 56 and the refrigerant derived from the control pressure chamber 16 via the extraction passage 55 The balance with the derived amount is controlled, and the internal pressure of the control pressure chamber 16 is determined.
In accordance with the internal pressure in the control pressure chamber 16, the difference from the internal pressure in the cylinder bore 28 via the piston 29 is changed, and the tilt angle of the swash plate 26 is changed.
As a result, the compressor 10 can change the stroke of the piston 29, that is, the discharge capacity of the refrigerant gas.
The inclination angle of the swash plate 26 is an angle between the plane perpendicular to the axial direction of the drive shaft 18 and the swash plate 26.

For example, when the internal pressure of the control pressure chamber 16 decreases, the inclination angle of the swash plate 26 increases and the discharge capacity of the compressor 10 increases.
A swash plate 26 shown by a two-dot chain line in FIG. 1 shows a state of the maximum inclination in contact with the rotary support 24.
Conversely, when the internal pressure of the control pressure chamber 16 increases, the inclination angle of the swash plate 26 decreases and the discharge capacity of the compressor 10 decreases.
A swash plate 26 shown by a solid line in FIG. 1 shows a state of a minimum inclination angle.

Incidentally, in the present embodiment, a cylindrical flow divider 60 is provided in the vicinity of the middle of the discharge passage 48 of the compressor 10.
The flow divider 60 divides the refrigerant flow in the discharge passage 48 to form a divided flow.
The flow divider 60 of the present embodiment is fixed to the rear housing 13 by press-fitting into the discharge passage 48 and is formed of the same aluminum-based metal material as the rear housing 13.
As shown in FIGS. 2A to 2C, the flow divider 60 includes a half-cylindrical curved wall body 61 that is in contact with the rear housing 13, and a flow dividing plate 62 that is connected to the curved wall body 61. It has.
The curved wall body 61 has a curved surface along the peripheral wall of the discharge passage 48 as a refrigerant flow path, and the flow divider 60 is fitted to the peripheral wall of the discharge passage 48 by the curved wall body 61.
That is, the flow divider 60 is formed in a cylindrical shape, part of which functions as a flow dividing plate 62, and the remaining curved wall body 61 is formed as a wall body having an arc cross section and is attached to the peripheral wall of the discharge passage 48. ing.

The flow dividing plate 62 divides the refrigerant flow path in the discharge passage 48 into the first flow path F1 and the second flow path F2 from the inlet formed on the upstream side to the outlet formed on the downstream side.
In the present embodiment, the flow path inside the flow divider 60 is a first flow path F1, and the flow path defined by the flow divider 60 and the rear housing 13 is a second flow path F2.
The flow dividing plate 62 is inclined with respect to the flow direction of the refrigerant in the discharge passage 48. Therefore, the flow path cross-sectional area of the first flow path F1 increases from the inlet toward the outlet, and the second flow path F2 The cross-sectional area of the flow path decreases as it goes from the inlet to the outlet.
In the present embodiment, the channel cross-sectional area at the inlet of the first channel F1 and the channel cross-sectional area at the inlet of the second channel F2 are set to be substantially the same.
The channel cross-sectional area at the outlet of the second channel F2 is set smaller than the channel cross-sectional area at the outlet of the first channel F1.
The purpose of decreasing the flow path cross-sectional area of the first flow path F1 from the inlet to the outlet and decreasing from the flow path cross-sectional area of the second flow path F2 toward the outlet is the purpose of the first flow path F1 and the second flow. The purpose is to generate a flow rate difference and a pressure difference of the refrigerant at the outlet of the path F2.

As shown in FIGS. 2 (a) and 2 (b), the flow dividing plate 62 of the present embodiment is formed with a large number of through holes 63 that communicate the first flow path F1 and the second flow path F2. .
A large number of through holes 63 formed in the flow dividing plate 62 allow a part of the refrigerant passing through the second flow path F2 to move to the first flow path F1.
In FIG. 3, the flow of the refrigerant is indicated by an arrow, but a part of the refrigerant passing through the second flow path F2 passes through a large number of through holes 63 to generate a vortex V in the vicinity of the through holes 63 in the first flow path F1. The generation of the vortex V is reduced by consuming pulsating pressure energy.
Although the through hole 63 is a circular hole, the diameter and number of the through holes 63 are determined by various conditions so that the vortex V can be generated to the extent that excessive pressure loss does not occur in the discharge passage 48. The
Since the pressure between the vicinity of the middle of the flow dividing plate 62 and the outlet in the second flow path F2 is higher than the pressure between the inlet and the vicinity of the middle, most of the large number of through holes 63 are near the middle of the flow dividing plate 62. It is formed so as to be distributed on the downstream side.
In the present embodiment, the through hole 63 is a circular hole, but it may be a hole other than a circle.

In the present embodiment, tubular connection members 64 are respectively provided adjacent to the flow divider 60 at the upstream inlet and the downstream outlet of the flow divider 60.
The connection member 64 is a member for reducing the resistance of the refrigerant flow by the flow divider 60.
The connection member 64 is formed of the same aluminum metal material as that of the flow divider 60.
One end face of the connection member 64 is in contact with the end face of the curved wall body 61 of the flow divider 60, thereby reducing the resistance of the refrigerant flow by the end face of the curved wall body 61.
Moreover, as shown in FIG.2 (c), the connection member 64 is formed with the opening 65 along the longitudinal direction of the connection member 64, and the opening 65 is located on the second flow path F2 side.
By adjusting and setting the width of the opening 65, the flow path cross-sectional area of the inlet of the second flow path F2 is adjusted.
The upstream and downstream connection members 64 are formed to have the same flow path cross-sectional area.
An annular groove 66 is formed on the inner wall surface of the rear housing 13 that forms the discharge passage 48, and a retaining ring 67 is attached to the annular groove 66.
The retaining ring 67 is a member that prevents the downstream connection member 64 from coming out of the discharge passage 48.

Next, the operation of the pulsation pressure reducing device according to this embodiment will be described.
When the compressor 10 is operated, the drive shaft 18 rotates, and the rotational motion of the drive shaft 18 is converted into a reciprocating motion of the piston 29 via the hinge mechanism 27 and the shoe 30.
As the piston 29 moves from the top dead center position to the bottom dead center position, the refrigerant accommodated in the suction chamber 35 through the suction passage 46 through which the refrigerant before compression passes, passes through the suction port 38 by opening the suction valve 40. Sucked into the cylinder bore 28.
The refrigerant gas sucked into the cylinder bore 28 through the suction port 38 is compressed to a predetermined pressure (discharge pressure) by the movement of the piston 29 from the bottom dead center position to the top dead center position.
Then, the refrigerant compressed to the discharge pressure is discharged to the discharge chamber 36 through the discharge port 39 by opening the discharge valve 41.
The refrigerant compressed in each of the plurality of cylinder bores 28 is discharged into the discharge chamber 36, but the timing of the reciprocating movement of the piston 29 accommodated in each cylinder bore 28 is different.
For this reason, the discharge timing of the refrigerant from each cylinder bore 28 to the discharge chamber 36 is different, and the high-pressure refrigerant is sequentially discharged from the discharge chamber 36 to generate pulsation.

The refrigerant with pulsating pressure discharged into the discharge chamber 36 flows from the discharge chamber 36 through the discharge passage 48.
The refrigerant flowing through the discharge passage 48 reaches the flow divider 60 through the connection member 64.
As shown in FIG. 3, the refrigerant that has reached the flow divider 60 flows through the first flow path F <b> 1 inside the flow divider 60 by the flow dividing plate 62 and the second flow path F <b> 2 that is outside the flow divider 60. Is diverted to the flow of refrigerant through
The channel cross-sectional areas of the inlets of the first channel F1 and the second channel F2 are substantially the same, but the channel cross-sectional area of the first channel F1 increases from the inlet to the outlet, while the second flow The channel cross-sectional area of the path F2 decreases from the inlet toward the outlet.
Since the flow path cross-sectional area of the first flow path F1 increases toward the downstream side, the flow rate of the refrigerant in the first flow path F1 decreases toward the downstream side, and the pressure in the first flow path F1 decreases to the downstream side. It goes down as it goes to.
On the other hand, since the cross-sectional area of the second flow path F2 decreases toward the downstream side, the flow rate of the refrigerant in the second flow path F2 increases toward the downstream side, and the pressure in the second flow path F2 Increases toward the downstream side.

Since the pressure in the first flow path F1 decreases toward the downstream side and the pressure in the second flow path F2 increases toward the downstream side, the pressure difference between the first flow path F1 and the second flow path F2 is increased. It becomes larger toward the downstream side.
For this reason, a part of the refrigerant passing through the second flow path F2 flows from the second flow path F2 to the first flow path F1 through the flow dividing plate 62.
As the refrigerant flows from the second flow path F2 to the first flow path F1, a vortex V is generated in the vicinity of the through hole 63 of the first flow path F1.
Since the vortex V is generated by consuming the energy of the refrigerant flow, the pulsation pressure of the refrigerant is reduced by the generation of the vortex V.

The flow rate of the refrigerant at the outlet of the second flow path F2 is larger than the flow speed at the outlet of the first flow path F1.
At the outlet of the flow divider 60, the refrigerant flow in the first flow path F1 and the flow of the refrigerant in the second flow path F2 that have caused a difference in speed are combined to reduce the pulsation pressure of the refrigerant.
The refrigerant whose pulsation pressure is reduced by the flow divider 60 is discharged to the external refrigerant circuit 44 and flows through the external refrigerant circuit 44.

The pulsation pressure reducing device of this embodiment has the following effects.
(1) The refrigerant passing through the discharge passage 48 passes through the flow divider 60, and is divided into the refrigerant that passes through the first flow path F1 and the refrigerant that passes through the second flow path F2. The channel cross-sectional area of the first channel F1 increases from the inlet to the outlet, the channel cross-sectional area of the second channel F2 decreases from the inlet to the outlet, and the channel cross-sectional area of the second channel F2 Is set smaller than the channel cross-sectional area at the outlet of the first channel F1. For this reason, the speed and pressure of the refrigerant passing through the first flow path F1 and the second flow path F2 are different from each other, and the flow of the refrigerant passing through the first flow path F1 and the second flow path F2 are different from each other in speed and pressure. Since the refrigerant flows that pass through merge, the pulsation pressure is reduced. The pulsation pressure of the refrigerant after passing through the flow divider 60 can be reduced only by providing the flow divider 60 in the discharge passage 48.

(2) Since the flow dividing plate 62 has a plurality of through holes 63, a part of the refrigerant passing through the second flow path F2 passes due to the pressure difference between the first flow path F1 and the second flow path F2. It flows to the first flow path F1 through the hole 63. At this time, when the refrigerant passes through the through hole 63, a vortex V is generated in the vicinity of the through hole 63 of the first flow path F1. Since the generation of the vortex V consumes the fluid energy of the refrigerant, the pulsation pressure can be reduced.
(3) Since the curved wall body 61 and the flow dividing plate 62 are the flow divider 60 integrally formed, the flow divider 60 can be installed in the discharge passage 48 by press fitting, and the flow divider 60 can be installed in the compressor 10. Easy. Further, the flow divider 60 can be accommodated inside the compressor 10, and a space for installing the flow divider 60 outside the compressor 10 or in the external refrigerant circuit 44 is not required.
(4) Since the connection members 64 are respectively provided at the inlet and the outlet of the flow divider 60, a part of the end face of the flow divider 60 is covered by the connection member 64, and the resistance of the refrigerant flow by the flow divider 60 can be reduced. . Further, by providing the opening 65 formed in the connection member 64, the flow path cross-sectional area of the second flow path F2 can be adjusted.

(Second Embodiment)
Next, the pulsation pressure reducing device according to the second embodiment will be described.
This embodiment is different from the first embodiment in that a through hole is not provided in a flow dividing plate included in the flow divider.
In the present embodiment, for the same configuration as that of the first embodiment, the description of the first embodiment is used and a common code is used.

As shown in FIG. 4, the flow divider 70 according to the present embodiment includes a semicircular cylindrical curved wall body 71 that is in contact with the rear housing 13, and a flow dividing plate 72 that is connected to the curved wall body 71. .
The curved wall body 71 has the same shape as the curved wall body 61 of the first embodiment.
A part of the flow divider 70 functions as a flow dividing plate 72, and the remaining curved wall body 71 is formed as a wall body having an arc cross section and is attached to the peripheral wall of the discharge passage 48.
The flow dividing plate 72 divides the refrigerant flow path in the discharge passage 48 into a first flow path F1 and a second flow path F2 from the upstream inlet to the downstream outlet to form a divided flow.
In the present embodiment, the flow path inside the flow divider 70 is a first flow path F1, and the flow path defined by the flow divider 70 and the rear housing 13 is a second flow path F2.
The flow dividing plate 72 is inclined with respect to the flow path direction of the refrigerant in the discharge passage 48. Therefore, the flow path cross-sectional area of the first flow path F1 increases from the inlet toward the outlet, and the second flow path F2 The channel cross-sectional area decreases from the inlet toward the outlet.
The flow dividing plate 72 of the present embodiment is not provided with a through hole, and the first flow path F1 and the second flow path F2 are completely separated.

In the present embodiment, the refrigerant reaching the flow divider 70 passes through the first flow path F1 inside the flow divider 70 by the flow dividing plate 72 and the second flow path F2 outside the flow divider 70. Divided into the flow of refrigerant.
The refrigerant flow rate in the first flow path F1 decreases as it goes downstream, the pressure in the first flow path F1 decreases as it goes downstream, and the refrigerant flow speed in the second flow path F2 increases as it goes downstream. However, the pressure in the second flow path F2 increases toward the downstream side.
The flow rate of the refrigerant at the outlet of the second flow path F2 is larger than the flow speed at the outlet of the first flow path F1.
By causing the refrigerant flow rate difference and pressure difference at the outlets of the first flow path F1 and the second flow path F2 to differ from each other, the pulsation pressures in the first flow path F1 and the second flow path F2 are different from each other, Further, the phase of the pulsation pressure is different. At the outlet of the flow divider 70, the refrigerant flow in the first flow path F1 and the refrigerant flow in the second flow path F2, which have generated a speed difference, join together, thereby pulsating the refrigerant. The pressure is reduced.
The refrigerant whose pulsation is reduced by the flow divider 70 is discharged to the external refrigerant circuit 44 and flows through the external refrigerant circuit 44.

In this embodiment, there exists an effect equivalent to the effect (1), (3), (4) of 1st Embodiment.
Further, since the through hole is not provided in the flow dividing plate 72, the first flow path F1 and the second flow path F2 can be completely separated, and pressure loss due to the vortex of the refrigerant passing through the through hole occurs. There is no.
Furthermore, compared with the flow divider 60 of the first embodiment, the flow divider 70 of the present embodiment does not need to form a through hole in the flow dividing plate 72, and the flow divider 70 can be easily manufactured because no through hole is formed. It becomes.

(Third embodiment)
Next, a pulsation pressure reducing device according to a third embodiment will be described.
The present embodiment is an example in which the flow divider is not a compressor but is provided in a refrigerant pipe having a discharge pressure of an external refrigerant circuit.
The external refrigerant circuit is a part of the refrigerant flow path in the refrigerant cycle, and the refrigerant pipe of the discharge pressure of the external refrigerant circuit corresponds to the refrigerant pipe of the refrigeration cycle.
In the present embodiment, for the same configuration as that of the first embodiment, the description of the first embodiment is used and a common code is used.

As shown in FIG. 5, the external refrigerant circuit 44 has a discharge side pipe 81 as a refrigerant pipe that connects between the compressor 10 and the condenser 51.
The discharge side pipe 81 passes the refrigerant having the discharge pressure discharged from the discharge port 47 of the compressor 10.
The compressor 10 of this embodiment is the compressor 10 as a part of the refrigerant flow path in the same refrigerant cycle as that of the first embodiment, but the flow divider 60 is not provided in the discharge passage 48 of the compressor 10. .
Connected to the discharge side pipe 81 is a metal pipe body 82 having a larger diameter than the diameter of the discharge side pipe 81.
The pipe body 82 is for passing a refrigerant, corresponds to a refrigerant pipe of a refrigeration cycle, has a sufficient length, and a tubular flow divider 83 is accommodated in the pipe body 82.
The flow divider 83 is for dividing the flow of the refrigerant in the tube body 82 to form a divided flow.
The current divider 83 of this embodiment is formed of the same metal material as the tube body 82.
The flow divider 83 includes a half-cylindrical curved wall body 84 that comes into contact with the peripheral wall of the tube body 82, and a flow dividing plate 85 connected to the curved wall body 84.
A part of the flow divider 83 functions as a flow dividing plate 85, and the remaining curved wall body 84 is formed as a wall body having an arc cross section and is attached to the peripheral wall of the tube body 82.

The flow dividing plate 85 divides the flow path of the refrigerant in the tubular body 82 into a first flow path F1 and a second flow path F2 from the upstream inlet to the downstream outlet.
In the present embodiment, the flow path inside the flow divider 83 is a first flow path F1, and the flow path defined by the flow divider 83 and the tube body 82 is a second flow path F2.
In the present embodiment, as compared with the first embodiment, the flow divider 83 can be made sufficiently longer than the refrigerant passage inside the compressor 10 by arranging the flow divider 83 in the external refrigerant circuit 44.
For this reason, the flow dividing plate 85 is inclined with respect to the flow path direction of the refrigerant of the tube body 82. However, compared with the first embodiment, the flow dividing plate 85 is sufficiently long and the inclination angle of the flow dividing plate 85 is small. .
The channel cross-sectional area of the first channel F1 increases as it goes from the inlet to the outlet, and the channel cross-sectional area of the second channel F2 decreases as it goes from the inlet to the outlet.
In the present embodiment, the channel cross-sectional area at the inlet of the first channel F1 and the channel cross-sectional area at the inlet of the second channel F2 are set to be substantially the same.
The channel cross-sectional area at the outlet of the second channel F2 is set smaller than the channel cross-sectional area at the outlet of the first channel F1.
The purpose of decreasing the flow path cross-sectional area of the first flow path F1 from the inlet to the outlet and decreasing from the flow path cross-sectional area of the second flow path F2 toward the outlet is the purpose of the first flow path F1 and the second flow. The purpose is to generate a flow rate difference and a pressure difference of the refrigerant at the outlet of the path F2.

In this embodiment, since the flow dividing plate 85 is long enough, the 1st flow path F1 and the 2nd flow path F2 are set long compared with 1st Embodiment.
As the first flow path F1 and the second flow path F2 become longer, the flow rate difference and pressure difference of the refrigerant at the outlets of the first flow path F1 and the second flow path F2 may be generated while suppressing the pressure loss of the refrigerant. it can.

In the present embodiment, the tubular connection member 64 is provided on the downstream side of the flow divider 83, but the connection member 64 is not provided on the upstream side of the flow divider 83.
The connection member 64 is made of the same metal material as that of the flow divider 83.
One end face of the connecting member 64 is in contact with the end face of the curved wall 84 of the flow divider 83.
The opening 65 of the connection member 64 is located on the second flow path F2 side.
An annular groove 86 is formed in the inner wall near the outlet of the tube body 82 in the circumferential direction, and a retaining ring 67 is attached to the annular groove 86.
The retaining ring 67 is a member that comes into contact with the other end surface of the connection member 64 and prevents the connection member 64 from coming out of the tube body 82.

In the present embodiment, the pulsation pressure reducing device is provided with a flow divider 83 in a pipe body 82 connected to the discharge side pipe 81 in the external refrigerant circuit 44.
According to the present embodiment, the refrigerant passing through the discharge side pipe 81 passes through the flow divider 83 provided in the pipe body 82, and the flow divider 83 passes through the refrigerant that passes through the first flow path F <b> 1 and the second flow path F <b> 2. Is diverted to the refrigerant.
The cross-sectional area of the first flow path F1 increases from the inlet toward the outlet, the cross-sectional area of the second flow path F2 decreases from the inlet to the outlet, and the flow path at the outlet of the second flow path F2. The cross-sectional area is set smaller than the cross-sectional area of the outlet of the first flow path F1.
For this reason, the speed and pressure of the refrigerant passing through the first flow path F1 and the second flow path F2 are different from each other, and the flow of the refrigerant passing through the first flow path F1 and the second flow path F2 are different from each other in speed and pressure. Since the refrigerant flows that pass through merge, the pulsation pressure is reduced.
Since the flow divider 83 is provided in the external refrigerant circuit 44 without providing the flow divider in the compressor 10, the length of the flow divider 83 can be increased.
Further, by sufficiently increasing the length of the flow divider 83, the flow rate difference and pressure difference of the refrigerant at the outlets of the first flow path F1 and the second flow path F2 are generated while suppressing the pressure loss of the refrigerant. Can do.

(Fourth embodiment)
Next, a pulsation pressure reducing device according to a fourth embodiment will be described.
This embodiment is an example in which two shunts are provided in a pipe body as a refrigerant pipe of a refrigeration cycle.
In the present embodiment, the description of the first and third embodiments is used for the configuration common to the first and third embodiments, and the reference numerals are used in common.

As shown in FIG. 6, inside the pipe body 82, a flow divider 60 (60 </ b> A) disposed on the upstream side, and a downstream flow divider 60 (60 </ b> B) disposed on the downstream side of the upstream flow divider 60. Is provided.
The upstream flow divider 60A and the downstream flow divider 60B have the same structure.
Connection members 64 are disposed at the upstream inlet of the flow divider 60A and the downstream outlet of the flow divider 60B in the pipe 82, respectively.
A connecting member 87 is provided between the upstream flow divider 60A and the downstream flow divider 60B.
The connecting member 87 has the same structure as the connecting member 64 except that the length is longer than that of the connecting member 64, and the opening 88 of the connecting member 87 is located on the second flow path F2 side.
In the present embodiment, the refrigerant is divided in the pipe 82 by the upstream flow divider 60A, merged once in the connection member 87 after the flow division, and then branched by the downstream flow divider 60B after the merge.
Therefore, according to this embodiment, the pulsation pressure of the refrigerant | coolant which passes along refrigerant | coolant piping can be reduced in steps by combining several diverter 60A, 60B.

(Fifth embodiment)
Next, a pulsation pressure reducing device according to a fifth embodiment will be described.
The present embodiment is an example in which the structure of the flow divider is different from that of the flow divider of the first embodiment, and no connection member is provided.
In the present embodiment, the description of the first embodiment is used for the configuration common to the first embodiment, and the reference numerals are used in common.

A diverter 90 according to this embodiment shown in FIG. 7A and FIG. 7B is not a cylindrical structure, but is an annular body 91 that can be inserted into the discharge passage 48 of the compressor 10, and is fixed to the annular body 91. The divided flow plate 92 is provided.
A part of the flow divider 90 functions as a flow dividing plate 92, and the remaining annular body 91 is formed as a wall body having an arc cross section and is attached to the peripheral wall of the discharge passage 48.
The annular body 91 corresponds to the curved wall body 61 of the first embodiment, but the length of the annular body 91 in the flow direction is significantly smaller than the length of the curved wall body 61 in the flow direction.
That is, the annular body 91 has a small surface area in contact with the refrigerant, and further reduces the resistance of the refrigerant flow.

In the state where the flow divider 90 is mounted in the discharge passage 48, the end portion 94 of the flow dividing plate 92 fixed to the annular body 91 is located at the downstream outlet, and the end portion 93 opposite to the flow dividing plate 92 is the upstream side. Located at the entrance.
The end portion 93 of the flow dividing plate 92 is set to have a smaller plate thickness toward the front end (upstream side), and has a shape that reduces resistance to the flow of the refrigerant.
The flow dividing plate 92 forms a first flow path F1 and a second flow path F2 inside the discharge passage 48.
In the present embodiment, the width of the end portion 93 of the flow dividing plate 92 is set slightly smaller than the diameter of the discharge passage 48.
The end portion 93 of the flow dividing plate 92 is supported by the peripheral wall of the discharge passage 48, and divides the discharge passage 48 into two so that the cross-sectional areas of the inlets of the first flow path F1 and the second flow path F are the same.
In the present embodiment, the flow dividing plate 92 is formed with a large number of through holes 95 communicating the first flow path F1 and the second flow path F2.
Most of the large number of through holes 95 are formed so as to be distributed downstream from the middle of the flow dividing plate 92.
The downstream end of the annular body 91 abuts against a retaining ring 67 provided in the discharge passage 48 to prevent the flow divider 90 from coming out of the discharge passage 48.

According to the flow divider 90 of the present embodiment, a decrease in compression efficiency due to the flow divider 90 can be suppressed.
In particular, in this embodiment, the end portion 93 on the inlet side of the flow dividing plate 92 is set to have a smaller thickness toward the front end, so that the resistance of the refrigerant flow by the end portion 93 on the inlet side of the flow dividing plate 92 is reduced. can do.
Moreover, in this embodiment, since a connection member is not provided, the number of parts of a pulsation pressure reduction apparatus can be reduced.

  The above embodiment shows an embodiment of the present invention, and the present invention is not limited to the above embodiment, and various modifications can be made within the scope of the invention as described below. Is possible.

In the above embodiment, the flow divider is provided in the discharge passage and the refrigerant pipe on the discharge side of the external refrigerant circuit. However, the flow divider may be provided in the suction pipe and the refrigerant pipe on the suction side of the external refrigerant circuit. . In this case, the pulsation pressure of the refrigerant during suction can be reduced. Further, for example, it is not hindered to provide a flow divider in each of the discharge passage and the suction passage.
In the above embodiment, the flow dividing plate included in the flow divider is a flow dividing plate that is formed by inclining a flat plate, but the flow dividing plate is not limited to a flat plate. For example, the current divider 110 shown in FIG. 8A or the current divider 120 shown in FIG. In another example 1 shown in FIG. 8A, the flow dividing plate 111 of the flow divider 110 is a curved plate. A through hole 112 is formed in the flow dividing plate 111. Moreover, in the flow divider 120 of another example 2 shown in FIG. 8B, the flow dividing plate 121 has a combination of a plurality of planes. A through hole 122 is formed in the flow dividing plate 121.
In the above embodiment, the cross-sectional areas of the first flow path and the second flow path at the inlet of the flow divider are substantially the same, but this is not restrictive. For example, the flow channel cross-sectional area of the first flow channel may be set smaller than the flow channel cross-sectional area of the second flow channel, or conversely larger. The flow path cross-sectional areas of the first flow path and the second flow path need only be set so that a flow rate difference and a pressure difference of the refrigerant are generated at the outlets of the first flow path F1 and the second flow path F2.
In the above embodiment, the material of the shunt is the same metal material as the material of the rear housing of the compressor and the material of the pipe body in the external refrigerant circuit, but is not limited thereto. The material of the shunt may be a material that approximates the thermal expansion coefficient of the material of the rear housing or the tube material in the external refrigerant circuit.
In the fourth embodiment described above, the two shunts are provided in the tube body, but this is not restrictive. For example, the first embodiment and the third embodiment may be combined so that the flow divider in the discharge passage is an upstream flow divider and the flow divider in the external refrigerant circuit is a downstream flow divider. Further, the number of flow dividers is not limited to two, and three or more may be provided depending on conditions. In this case, the reduction of the pulsation pressure can be adjusted by adjusting the number of shunts provided. Moreover, the freedom degree of the position which installs a shunt can be improved by providing a some shunt.
In the above embodiment, the swash plate type variable capacity compressor as a compressor has been described, but the type of the compressor is not particularly limited. For example, a scroll compressor or a vane compressor may be used. Further, the compressor is not limited to a compressor for vehicle air conditioning.

DESCRIPTION OF SYMBOLS 10 Compressor 11 Cylinder block 12 Front housing 13 Rear housing 16 Control pressure chamber 18 Drive shaft 24 Rotating support 26 Swash plate 27 Hinge mechanism 28 Cylinder bore 29 Piston 35 Suction chamber 36 Discharge chamber 44 External refrigerant circuit 46 Suction passage 48 Discharge passage 57 Capacity control valve 60 (60A, 60B), 70, 83, 90, 110, 120 Flow divider 62, 72, 85, 92, 111, 121 Flow dividing plate 63, 95, 121, 122 Through hole 64, 87 Connection member 81 Discharge Side piping 82 Tube F1 First flow path F2 Second flow path

Claims (7)

A pulsation pressure reducing device in a refrigeration cycle for circulating a refrigerant in a refrigerant flow path,
The refrigerant flow path is provided with a flow divider that diverts and passes the refrigerant,
The flow divider includes a flow dividing plate that divides the refrigerant flow path into a first flow path and a second flow path from an inlet formed on the upstream side to an outlet formed on the downstream side.
The channel cross-sectional area of the first channel increases from the inlet toward the outlet,
The channel cross-sectional area of the second channel decreases from the inlet toward the outlet,
The apparatus for reducing pulsation pressure in a refrigeration cycle, wherein a cross-sectional area of the outlet of the second flow path is set smaller than a cross-sectional area of the outlet of the first flow path.   2. The pulsation pressure reducing device in a refrigeration cycle according to claim 1, wherein the flow dividing plate has a plurality of through holes communicating the first flow path and the second flow path.   The flow divider is formed in a cylindrical shape, a part functions as the flow dividing plate, and the remaining portion is formed as a wall body having an arcuate cross section and is attached to the peripheral wall of the refrigerant flow path. The pulsation pressure reducing device in the refrigeration cycle according to claim 1 or 2.   The pulsating pressure reduction in the refrigeration cycle according to any one of claims 1 to 3, wherein the flow dividing plate has an inlet side end portion whose thickness is set to decrease from the downstream side toward the upstream side. apparatus.   The pulsation pressure reducing device for a refrigeration cycle according to any one of claims 1 to 4, wherein the refrigeration cycle includes a compressor, and the flow divider is provided in a refrigerant flow path in the compressor. . The refrigerant flow path is formed in a housing of the compressor, and is a suction passage through which refrigerant before compression passes and a discharge passage through which compressed refrigerant passes.
The pulsating pressure reducing device in a refrigeration cycle according to claim 5, wherein the flow divider is provided in at least one of the suction passage and the discharge passage.   The pulsation pressure reducing device for a refrigeration cycle according to any one of claims 1 to 4, wherein the flow divider is provided in a refrigerant pipe of the refrigeration cycle.

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