JP5413850B2 - Refrigerant compressor - Google Patents

Description

  The present invention relates to a refrigerant compressor used in a vehicle air conditioner system, and more particularly to a cooling structure for lubricating oil.

  In the refrigerant compressor, lubricating oil is mixed in the refrigerant that is sucked and discharged. However, if the oil circulation rate (OCR) to the air conditioner system increases, the heat exchange is hindered, resulting in a decrease in cooling performance. Therefore, it is required to reduce the oil circulation rate.

  For this reason, the circulating oil contained in the discharged refrigerant is separated and returned, but the oil separated from the high-temperature discharged refrigerant is at a high temperature, and if it is returned as it is, the viscosity decreases, so the lubrication performance decreases. To do. Therefore, it is required to cool the separated oil.

  In the compressor described in Patent Document 1, an auxiliary head is attached to a cylinder head in which a suction chamber and a discharge chamber are formed so as to extend in the axial direction, and an oil storage chamber (oil reservoir chamber) is provided in the auxiliary head. And the separated oil is temporarily stored in the oil storage chamber. The oil storage chamber is adjacent to the suction chamber so that the oil in the oil storage chamber is cooled by the low-temperature suction refrigerant.

JP 58-131380 A

However, the compressor described in Patent Document 1 has the following problems.
In the cylinder head, a discharge chamber is disposed at the center thereof, and a suction chamber is disposed so as to surround the periphery of the cylinder head. Therefore, the area adjacent to the suction chamber is narrower than the oil storage space of the oil storage chamber, and the oil storage When the amount increases, the oil cannot be cooled effectively.
Further, if the oil storage chamber is disposed adjacent to the suction chamber of the cylinder head, the cylinder head is extended in the axial direction as a whole, and the size of the compressor in the axial direction increases, which is not preferable.

  In view of such a situation, it is an object of the present invention to provide a refrigerant compressor that can effectively cool oil in an oil storage chamber with a simple structure and can suppress an increase in the size of the compressor in the axial direction. .

  A refrigerant compressor according to the present invention includes a cylinder block having a plurality of parallel cylinder bores around an axis, a cylinder head disposed on one end side of the cylinder block via a valve plate, and the other end side of the cylinder block The piston is inserted into the cylinder bore and reciprocates, compresses the refrigerant sucked from the suction chamber on the cylinder head side and discharges it to the discharge chamber on the cylinder head side, and lubricating oil from the refrigerant discharged to the discharge chamber And an oil recirculation mechanism for separating the oil and returning it to the compressor lubrication section.

  Here, the cylinder head includes therein the suction chamber, the discharge chamber, a suction passage for introducing a refrigerant sucked from an external refrigerant circuit into the suction chamber, and a refrigerant discharged into the discharge chamber. And a discharge passage leading out toward the external refrigerant circuit. The suction chamber is disposed on the radial center portion side of the cylinder head, and the discharge chamber is annularly disposed on the outer side of the cylinder head in the radial direction so as to surround the suction chamber.

  The oil recirculation mechanism has an oil storage chamber for storing the separated oil. The oil storage chamber includes a cylindrical portion that extends in the radial direction integrally with the cylinder head and has an open end on the outer surface of the cylinder head, and a closing member that closes the open end. And the said cylindrical part is set as the structure which has a bulging part which bulges in the said suction chamber side.

  According to the present invention, the high-temperature oil in the oil storage chamber is effectively cooled by the low-temperature suction refrigerant due to the presence of the bulging portion toward the suction chamber, and the decrease in the viscosity of the oil can be suppressed. Moreover, since the suction chamber is disposed on the center side of the cylinder head, it is easy to dispose the oil storage chamber adjacent to the suction chamber and bulging.

  Further, by expanding the oil storage chamber to the suction chamber side, it is possible to suppress an increase in the size of the compressor by bringing the oil storage chamber to the suction chamber side.

Sectional drawing of the refrigerant compressor (especially variable capacity compressor) which shows one Embodiment of this invention View of cylinder head viewed from the end face on the valve plate side Sectional view of oil storage chamber (cross-sectional view taken along line AA in FIG. 2) Cross section of separation chamber Sectional drawing of the principal part of the refrigerant compressor which shows other embodiment of this invention.

Hereinafter, embodiments of the present invention will be described in detail.
FIG. 1 is a sectional view of a refrigerant compressor (particularly a variable capacity compressor) showing an embodiment of the present invention. 2 is a view of the cylinder head as viewed from the end surface on the valve plate side, FIG. 3 is a cross-sectional view of the oil storage chamber (A-A cross-sectional view of FIG. 2), and FIG. 4 is a cross-sectional view of the separation chamber.

First, the basic configuration of the variable capacity compressor will be described.
The variable capacity compressor 100 includes a cylinder block 101 having a plurality of parallel cylinder bores 101a around an axis, a front housing 102 provided at one end of the cylinder block 101, and a valve plate (valve / port) at the other end of the cylinder block 101. And a cylinder head (rear housing) 104 provided via a forming body 103. These are fastened together with a fastening bolt 140 via a gasket (not shown) to form a compressor housing.

  A drive shaft 106 is provided at the center of the cylinder block 101 and the front housing 102 across a crank chamber 105 formed therebetween, and a swash plate 107 is disposed around the drive shaft 106. The swash plate 107 is coupled to the rotor 108 fixed to the drive shaft 106 via a connecting portion 109, and the inclination angle can be changed along the drive shaft 106. A coil spring 110 is mounted between the rotor 108 and the swash plate 107 to urge the swash plate 107 toward the minimum tilt angle, and the tilt angle of the swash plate 107 is increased on the opposite side of the swash plate 107. A coil spring 111 that is biased toward the direction to be mounted is mounted.

  One end of the drive shaft 106 extends through the boss portion 102a protruding to the outside of the front housing 102 and extends to the outside, and is connected to an electromagnetic clutch (not shown). A shaft seal device 112 is inserted between the drive shaft 106 and the boss portion 102a to shut off the inside and the outside of the front housing 102. The drive shaft 106 is supported by bearings 113, 114, 115, and 116 in the radial direction and the thrust direction, and power from an external drive source is transmitted via an electromagnetic clutch so as to be rotatable.

  In the cylinder bore 101a of the cylinder block 101, a single-headed piston 117 is inserted and arranged so as to be able to reciprocate with the head facing the cylinder head 104 side. A U-shaped recess 117 a is formed at the end opposite to the head of the piston 117, and the outer periphery of the swash plate 107 is accommodated in the recess 117 a, and the piston 117 is connected to the piston 117 via a pair of front and rear shoes 118. The swash plate 107 is configured to be interlocked with each other. Accordingly, the piston 117 can reciprocate in the cylinder bore 101a by the rotation of the drive shaft 106.

  A suction chamber 119 and a discharge chamber 120 are defined in the cylinder head 104, and the suction chamber 119 is disposed on the radial center of the cylinder head 104 (on the extension of the axis of the drive shaft 106). Is arranged in an annular shape so as to surround the suction chamber 119 outside the cylinder head 104 in the radial direction.

  The valve seat 103 includes a suction port 103a that communicates the cylinder bore 101a (compression chamber by the piston 117) and the suction chamber 119 on the cylinder head 104 side, a cylinder bore 101a (compression chamber by the piston 117), and a discharge chamber on the cylinder head 104 side. A discharge port 103b communicating with 120 is formed, and a one-way valve (not shown) is provided for each of the suction port 103a and the discharge port 103b.

  The cylinder head 104 is also formed with a suction passage 104a for introducing the refrigerant sucked from the external refrigerant circuit into the suction chamber 119 and a discharge passage 104b for leading the refrigerant discharged into the discharge chamber 120 toward the external refrigerant circuit. Has been. Accordingly, the suction chamber 119 is connected to the air conditioner system side via the suction passage 104a, and the discharge chamber 120 is connected to the air conditioner system side via the discharge passage 104b.

In this variable capacity compressor 100, the rotation of the drive shaft 106 is converted into the reciprocating motion of the piston 117 by the swash plate 107 as a conversion mechanism, and the refrigerant is sucked / discharged. The discharge capacity can be changed by changing the stroke, and the inclination angle of the swash plate 107 is changed by the pressure in the crank chamber 105.
That is, the tilt angle of the swash plate 107 changes due to the moment caused by the pressure difference across all the pistons 117, so that the tilt angle of the swash plate 107 can be arbitrarily controlled by the pressure in the crank chamber 105.

For this control, the cylinder head 104 is provided with a capacity control valve 200. The capacity control valve 200 adjusts the amount of discharge gas introduced into the crank chamber 105 by changing the opening of the air supply passage 121 that connects the discharge chamber 120 and the crank chamber 105.
In addition, the refrigerant in the crank chamber 105 enters the suction chamber 119 via a clearance between the outer periphery of the drive shaft 106 and the bearings 115 and 116, a space 122, and an extraction passage that passes through the orifice 103c formed in the valve plate 103. Flowing.

  Therefore, the pressure in the crank chamber 105 is changed by adjusting the opening degree of the capacity control valve 200, and thereby the inclination angle of the swash plate 107 is changed, so that the discharge capacity can be changed. Note that the pressure of the suction chamber 119 is guided to the capacity control valve 200 through the communication passage 123, and the capacity control valve 200 introduces the discharge gas into the crank chamber 105 so that the pressure of the suction chamber 119 maintains a predetermined pressure. The amount is adjusted.

Next, an oil recirculation mechanism that separates the lubricating oil from the discharged refrigerant and returns it to the compressor lubricating portion will be described.
The oil recirculation mechanism includes an oil separation portion that separates oil from the discharged refrigerant, an oil storage chamber that stores the separated oil, and an oil return passage that returns the oil from the oil storage chamber to the suction side (low pressure region). Is done.

  The discharge passage 104b is arranged in an upper region of the cylinder head 104, and has an upward lead-out hole 104b1 connected to an external refrigerant circuit. The discharge passage 104b is positioned below the lead-out hole 104b1 and has a cylindrical shape formed larger in diameter than the lead-out hole 104b1. The separation chamber 104b2, the separation pipe 130 protruding into the separation chamber 104b2 and press-fitted and fixed in the outlet hole 104b1, and extending substantially perpendicular to the axis of the separation chamber 104b2 and opening along the inner wall of the separation chamber 104b2, and the separation chamber 104b2 And an introduction hole 104b3 communicating with the discharge chamber 120.

  Accordingly, the gaseous refrigerant containing the oil discharged from the cylinder bore 101a into the discharge chamber 120 flows into the separation chamber 104b2 from the introduction hole 104b3, separates the oil while turning around the separation pipe 130, and gas The refrigerant is discharged into the external refrigerant circuit through the inside of the separation pipe 130 and the outlet hole 104b1. The introduction hole 104b3, the separation chamber 104b2, and the separation pipe 130 constitute an oil separation unit that separates oil from the discharged refrigerant.

An oil storage chamber 132 is provided to store the oil separated by the oil separation unit.
The oil storage chamber 132 includes a cylindrical portion that extends in the radial direction integrally with the cylinder head 104 and has an open end on the outer surface of the cylinder head, and a closing member 134 that closes the open end. Specifically, the oil storage chamber (tubular portion) 132 passes through the center of the suction chamber 119 and extends in a substantially cylindrical shape in the radial direction of the cylinder head 104 so as to cross the suction chamber 119 obliquely. The open end has an open end toward the outer side and the lower side, and the open end is closed by a closing member 134. And the oil storage chamber 132 is formed so that an opening cross-sectional area increases as it goes to the open end, and the oil storage space is expanded in the lower region.

The oil storage chamber 132 also has a bulging portion 132a that bulges into the suction chamber 119 in order to cool the stored oil.
The oil storage chamber 132 is disposed so as to cross the suction chamber 119 obliquely so as to intersect the center of the suction chamber 119, that is, the extension line of the axis of the drive shaft 106, so that the cylinder head 104 is moved from the direction of FIG. When viewed, most of the region from the lower region to the upper region of the oil storage chamber 132 bulges into the suction chamber 119. 3 is a cross section of the oil storage chamber 132 (AA cross section in FIG. 2). The axial center of the oil storage chamber 132 formed in a substantially cylindrical shape swells into the suction chamber 119. More than half of the peripheral wall faces the suction chamber 119.

Therefore, the high temperature oil stored in the oil storage chamber 132 is effectively cooled by the low temperature refrigerant in the suction chamber 119.
In addition, by expanding the oil storage chamber 132 into the cylinder head 104, an increase in the size of the variable capacity compressor 100 due to the provision of the oil storage chamber 132 can be suppressed. Can be limited.

  The opening end of the separation chamber 104b2 is directly open in the region facing the closing member 134 of the oil storage chamber 132, and the oil separated in the separation chamber 104b2 falls directly into the oil storage chamber 132 and is stored. ing. That is, the opening end of the separation chamber 104b2 serves as an oil inflow hole into the oil storage chamber 132.

On the other hand, in order to return the oil separated and stored in the oil storage chamber 132, the lower region of the oil storage chamber 132 communicates with the suction chamber 119 through an oil return passage and an orifice 136 serving as a pressure reducing means.
Accordingly, the high-temperature oil separated in the separation chamber 104b2 is stored in the oil storage chamber 132, cooled by the low-temperature refrigerant in the suction chamber 119 by the bulging portion 132a, and the orifice due to the pressure difference between the oil storage chamber 132 and the suction chamber 119. It is refluxed to the suction chamber 119 via 136. The recirculated oil is sucked into the cylinder bore 101 a and lubricates the variable capacity compressor 100.

  2 and 3, the suction passage 104a extends in the radial direction of the cylinder head 104, and an imaginary line extending the suction passage 104a into the suction chamber 119 intersects the bulging portion 132a. It is arranged. Therefore, the main flow of the refrigerant flowing into the suction chamber 119 from the suction passage 104a directly collides with the bulging portion 132a, so that the oil stored in the oil storage chamber 132 is cooled more effectively.

  According to the present embodiment, the oil storage chamber 132 is integrally formed with the cylinder head 104 in the radial direction and has a cylindrical portion having an open end on the outer surface of the cylinder head, and a closing member 134 that closes the open end. The cylindrical portion has a bulging portion 132a that bulges into the suction chamber 119, so that the hot oil in the oil storage chamber 132 is effectively cooled by the low-temperature sucked refrigerant, and the viscosity of the oil While being able to suppress a fall, the physique increase of a compressor can be suppressed.

  In addition, according to the present embodiment, the bulging portion 132a includes at least the lower region of the oil storage chamber 132, so that the oil returned to the suction side (low pressure region) can be cooled regardless of the oil storage amount.

  Further, according to the present embodiment, the oil storage chamber 132, that is, the cylindrical portion thereof, is formed so that the opening cross-sectional area gradually increases toward the open end, and the open end opens downward. Thus, even when the amount of storage is small, the oil always accumulates, and the lower region that bulges toward the suction chamber 119 is enlarged in space, so that the oil returned to the suction side can be reliably cooled.

  Further, according to the present embodiment, the oil storage chamber 132 is disposed so that the bulging portion 132a intersects the axis of the cylinder head 104 (extension line of the axis of the drive shaft 106), whereby the bulging portion 132a. Since the oil storage chamber 132 is disposed so as to pass through the vicinity of the center of the suction chamber 119, the area that swells to the suction chamber 119 increases, and the cooling effect increases.

  Further, according to the present embodiment, since the oil storage chamber 132 is disposed so as to cross the suction chamber 119, the cooling area can be further increased, and the high-temperature oil can be cooled more effectively.

  In addition, according to the present embodiment, heat exchange is promoted by arranging the suction passage 104a so that a virtual line extending the suction passage 104a into the suction chamber 119 intersects the bulging portion 132a. The oil is effectively cooled.

  On the other hand, when the lubricating oil is cooled by the suction refrigerant, the temperature of the suction refrigerant rises conversely. However, since the amount of the lubricating oil to be cooled is limited, the temperature rise of the suction refrigerant is slight, and this causes an inconvenience. The benefits of cooling the lubricating oil are much greater than the benefits.

Next, another embodiment of the present invention will be described with reference to FIG.
FIG. 5 is a cross-sectional view of an essential part of a refrigerant compressor showing another embodiment of the present invention. The same elements as those in FIG. 1 are denoted by the same reference numerals, description thereof is omitted, and different elements will be described.

  The cylindrical oil storage chamber 132 is composed of a large-diameter lower region and a small-diameter upper region, the bulging portion 132a is composed of a lower region 132a1 and an upper region 132a2, and the bulging portion 132a2 in the upper region of the oil storage chamber 132 is a lower portion. The bulge volume from the bulge portion 132a1 in the region to the suction chamber 119 is small.

  As a result, the oil stored in the lower region returned to the suction chamber 119 is effectively cooled, and the upper region has a smaller bulge volume than the lower region. Heat exchange by the refrigerant is suppressed, and the intake refrigerant can be prevented from being unnecessarily heated.

  The oil storage chamber 132 may be tapered from the separation chamber 104b2 side to the lower region to adjust the bulge volume. Further, the oil storage chamber 132 may be inclined to adjust the bulge volume. Further, the upper region may not be bulged.

  According to this embodiment, the oil storage chamber 132 expands toward the lower region, and the oil stored in the lower region returning to the low pressure region is effectively cooled, and the upper region of the oil storage chamber 132 is increased. Does not swell into the suction chamber 119 or has a smaller bulge volume than the lower region, so that the swelled portion in the upper region is restrained from heat exchange by the sucked refrigerant, and the sucked refrigerant is heated unnecessarily. Can be suppressed.

The illustrated embodiments are merely examples of the present invention, and the present invention is not limited to those directly described by the described embodiments, and various improvements and modifications made by those skilled in the art within the scope of the claims. Needless to say, it encompasses changes.
For example, in the embodiment, the oil separation unit is a centrifugal separation method using the separation pipe 130, but the separation pipe 130 may not be provided. Also, other oil separation methods such as a collision separation method may be used, or the oil storage chamber 132 may be communicated with a region in the discharge chamber 120 where oil is likely to stop.

Further, in the embodiment, the oil storage chamber 132 is disposed so as to be inclined so that the open end is on the lower side. However, the present invention is not necessarily limited to this, and for example, the open end may be directly beside.
Further, in the embodiment, the oil storage chamber 132 is configured by a cylindrical cylindrical portion, but the cylindrical portion may be a rectangular tube shape such as a substantially square shape.
In addition, a protruding portion that protrudes into the suction chamber 119 may be provided in the suction passage 104a, and in this way, the oil can be more effectively cooled by the suction refrigerant flow.

  In the embodiment, as the oil return passage, the oil storage chamber 132 and the suction chamber 119 communicate with each other via the orifice 136. However, a valve may be arranged instead of the orifice, It is good also as a structure which connects the crank chamber 105.

  In the embodiment, the refrigerant compressor is a variable capacity compressor, but may be a fixed capacity compressor. Moreover, it is good also as a clutchless compressor without an electromagnetic clutch, or a compressor driven with a motor.

100 Variable displacement compressor 101 Cylinder block 101a Cylinder bore 102 Front housing 102a Boss portion 103 Valve plate 103a Suction port 103b Discharge port 103c Orifice 104 Cylinder head 104a Suction passage 104b Discharge passage 104b1 Lead-out hole 104b2 Separation chamber 104b3 Inlet hole 105 Crank chamber 106 Drive Shaft 107 Swash plate 108 Rotor 109 Coupling portion 110, 111 Coil spring 112 Shaft seal device 113, 114, 115, 116 Bearing 117 Piston 117a Recess 118 Shoe 119 Suction chamber 120 Discharge chamber 121 Air supply passage 122 Space 123 Communication passage 130 Separation pipe 132 oil storage chamber 132a bulging portion 134 closing member 136 orifice 140 fastening bolt 200 capacity control valve

Claims (6)

A cylinder block having a plurality of parallel cylinder bores around an axis;
A cylinder head disposed on one end side of the cylinder block via a valve plate;
A piston that is inserted into the cylinder bore from the other end side of the cylinder block and reciprocates, compresses the refrigerant sucked from the suction chamber on the cylinder head side, and discharges it to the discharge chamber on the cylinder head side;
An oil recirculation mechanism that separates the lubricating oil from the refrigerant discharged into the discharge chamber and returns it to the compressor lubricating portion;
A refrigerant compressor comprising:
The cylinder head includes therein the suction chamber, the discharge chamber, a suction passage for introducing the refrigerant sucked from an external refrigerant circuit into the suction chamber, and the refrigerant discharged into the discharge chamber as an external refrigerant circuit. A discharge passage leading out toward
The suction chamber is disposed on the radial center portion side of the cylinder head, and the discharge chamber is disposed in an annular shape so as to surround the suction chamber on the outer side in the radial direction of the cylinder head,
The oil recirculation mechanism has an oil storage chamber for storing separated oil,
The oil storage chamber is composed of a cylindrical portion that extends in the radial direction integrally with the cylinder head and has an open end on the outer surface of the cylinder head, and a closing member that closes the open end,
The refrigerant compressor according to claim 1, wherein the tubular portion has a bulging portion that bulges toward the suction chamber.   The refrigerant compressor according to claim 1, wherein the bulging portion includes at least a lower region of the oil storage chamber.   The refrigerant compressor according to claim 2, wherein the oil storage chamber is disposed so that the bulging portion intersects an axis of the cylinder head.   4. The refrigerant compressor according to claim 3, wherein the oil storage chamber is disposed so as to cross the suction chamber.   5. The suction passage according to claim 1, wherein the suction passage is disposed so that a virtual line extending the suction passage into the suction chamber intersects the bulging portion. The refrigerant compressor described in 1.   The refrigerant compressor according to claim 2, wherein the upper region of the oil storage chamber does not bulge toward the suction chamber or has a smaller bulge volume than the lower region.