The present disclosure relates generally to swash plate type compressors; and more specifically, to fixed displacement swash plate type compressors.
BACKGROUND
Generally, mechanical devices such as boilers, pumps, compressors, fans and so forth are used around the world on a daily basis. For example, pumps are used for transporting liquids between different locations and compressors are used for pressurizing (or increasing a pressure) fluids. Such compressors may find an application within cooling systems such as air-conditioners, refrigerators and so forth, for pressurizing a refrigerant flowing through the cooling systems. Recently, a need for improvement of compressors has increased manifold, owing to new uses and applications thereof. For example, an increasing number of automobiles these days are being pre-installed with air-conditioners, and so forth that employ compressors therein.
It will be appreciated that the cooling systems used within automobiles such as cars, vans, trucks and so forth are associated with a different set of design constraints as compared to cooling systems used within stationary structures such as homes, offices, hospitals and so forth. Firstly, the cooling systems used within automobiles are required to have a compact form-factor such that more space within the automobiles can be dedicated for passengers, luggage and other equipment. Secondly, such cooling systems are required to be lightweight to reduce a load on the automobiles. Moreover, the cooling systems should require less operating power, less frequent servicing and/or repair and should be associated with reliable, efficient and long-term operation. Consequently, the compressors used within such

cooling systems are required to have a compact form-factor and should be lightweight and efficient.
Thus, the compressors used within automobile cooling systems are being manufactured with lesser components and reduced operating spaces (or clearance) between components thereof. However, such a design constraint associated with use of lesser components may lead to elimination of lubrication arrangements within the compressors. Furthermore, the reduced operating spaces between the components of the compressors that may be devoid of lubrication arrangements, can give rise to various problems. For example, friction between moving components of the compressor may increase, thereby causing wear and tear of the components. Such an increase in friction may cause generation and build-up of heat between the components, thereby, further causing damage to the compressor. It will be appreciated that such wear and tear, and damage to the compressor may ultimately lead to breakdown of the cooling system.
Therefore, in light of the foregoing discussion, there exist various problems associated with compressors used in automobile cooling systems.
SUMMARY
The present disclosure seeks to provide an improved fixed displacement swash plate type compressor comprising a plurality of lubrication channels.
According to a first aspect, an embodiment of the present disclosure provides a fixed displacement swash plate type compressor comprising:
- a cylinder block comprising a plurality of cylindrical bores arranged radially along the cylinder block;

- a piston coupled to each of the plurality of cylindrical bores, wherein the pistons are operable to reciprocate in response to movement of the swash plate;
- a shaft bore arranged at a centre of the cylinder block, wherein the shaft bore is operable to receive a driveshaft therein;
- a plurality of semi-cylindrical lubrication channels disposed along a circumference of the shaft bore, and
- at least one bush bearing arranged along the driveshaft, wherein the at least one bush bearing comprises an annular groove in fluidic communication with the plurality of semi-cylindrical lubrication channels;
wherein the plurality of semi-cylindrical lubrication channels allows flow of a lubricant therein, to provide lubrication between the driveshaft and the shaft bore,
and wherein the annular groove of the bush bearing allows flow of the lubricant to or from the plurality of semi-cylindrical lubrication channels, to provide lubrication between the driveshaft and the bush bearing.
The present disclosure seeks to provide the fixed displacement swash plate type compressor that comprises lubrication channels, wherein lubricant flowing through the lubrication channels enables to reduce friction and temperature between the driveshaft and shaft bore, thus, providing reliable and efficient operation of the compressor and increases an operating life thereof.
It will be appreciated that features of the present disclosure are susceptible to being combined in various combinations without departing from the scope of the present disclosure as defined by the appended claims.

DESCRIPTION OF THE DRAWINGS
The summary above, as well as the following detailed description of illustrative embodiments, is better understood when read in conjunction with the appended drawings. For the purpose of illustrating the present disclosure, exemplary constructions of the disclosure are shown in the drawings. However, the present disclosure is not limited to specific methods and instrumentalities disclosed herein. Moreover, those in the art will understand that the drawings are not to scale. Wherever possible, like elements have been indicated by identical numbers.
Embodiments of the present disclosure will now be described, by way of example only, with reference to the following diagrams wherein:
FIGs. 1 to 3 are schematic illustrations of a fixed displacement swash plate type compressor, in accordance with various embodiments of the present disclosure;
FIG. 4 is a perspective view of a cylinder block (such as the cylinder block of FIG. 1) and a bush bearing (such as the bush bearings of FIG. 1), in accordance with an embodiment of the present disclosure;
FIG. 5 is a perspective view of a cylinder block (such as the cylinder block of FIG. 2) and the bush bearing of FIG. 2, in accordance with an embodiment of the present disclosure;
FIG. 6 is an exploded view of the cylinder block and the bush bearing of FIG. 3, in accordance with an embodiment of the present disclosure; and
FIG. 7 is an exploded view of the cylinder block and the bush bearing of FIG. 5, in accordance with an embodiment of the present disclosure.

In the accompanying drawings, an underlined number is employed to
represent an item over which the underlined number is positioned or an
item to which the underlined number is adjacent. A non-underlined
number relates to an item identified by a line linking the non-underlined
number to the item. When a number is non-underlined and
accompanied by an associated arrow, the non-underlined number is used to identify a general item at which the arrow is pointing.
DESCRIPTION OF EMBODIMENTS
In overview, embodiments of the present disclosure are concerned with fixed displacement swash plate type compressors with lubrication channels.
Referring to FIG. 1, there is shown a schematic illustration of a fixed displacement swash plate type compressor 10, in accordance with an embodiment of the present disclosure. The fixed displacement swash plate type compressor 10 can be used in an air-conditioning system, such as in an automobile air-conditioning system, for pressurising a refrigerant flowing there through. In such an instance, the refrigerant is allowed to flow into the fixed displacement swash plate type compressor 10 via a suction port 12. Subsequently, the refrigerant is pressurized during operation of the fixed displacement swash plate type compressor 10 and the high-pressure refrigerant is allowed to flow out of the fixed displacement swash plate type compressor 10 via a discharge port (not shown).
The fixed displacement swash plate type compressor 10 comprises a
swash plate 14, cylinder block 30A-B comprising a plurality of
cylindrical bores (shown in FIG. 4) arranged radially along the cylinder
block 30A-B. The swash plate 14 is a disc having a predefined
thickness that is arranged in an inclined configuration in a swash chamber 16 of the fixed displacement swash plate type compressor 10.
6

It will be appreciated that, during operation of the fixed displacement swash plate type compressor 10, the swash plate 14 is operable to rotate such that a point along an external surface thereof generates an inclined circle about an axis of rotation of the swash plate 14. Furthermore, cylinder block 30A-B comprises the plurality of cylindrical bores. Each of the plurality of cylindrical bores is a through-hole having a fixed diameter that is made through the cylinder block 30A-B. Furthermore, each cylindrical bore is arranged at a fixed distance from the axis of rotation of the swash plate 14.
The fixed displacement swash plate type compressor 10 comprises a piston 18A-B coupled to each of the plurality of cylindrical bores, wherein the pistons 18A-B are operable to reciprocate in response to movement of the swash plate 14. The plurality of pistons 18A-B is coupled to each of the plurality of cylindrical bores such that, during the inclined rotation of the swash plate 14, each piston 18A-B reciprocates between a bottom dead centre (BDC) and a top dead centre (TDC) of the cylinder block 30A-B. For example, the piston 18A coupled to a first side of the swash plate 14 is positioned at a bottom dead centre (BDC) of the cylinder block 30A prior to commencement of rotation of the swash plate 14. Subsequently, upon rotation of the swash plate 14, the first side of the swash plate 14 is raised such that the piston 18A is positioned at a top dead centre (TDC) of the cylinder block 30A. Similarly, the piston 18B coupled to a second side of the swash plate 14 is positioned at a top dead centre (TDC) of the cylinder block 30B prior to commencement of rotation of the swash plate 14. Subsequently, upon rotation of the swash plate 14, the second side of the swash plate 14 is lowered such that the piston 18B is positioned at the bottom dead centre (BDC) of the cylinder block 30B. It will be appreciated that all other pistons occupy intermediate positions between the top dead centre (TDC) and the bottom dead centre (BDC)
7

of the cylinder block 30A-B prior to commencement and after
completion of a single rotation of the swash plate 14.
Furthermore, during operation of the fixed displacement swash plate type compressor 10, the inclined rotation of the swash plate 14 about the axis of rotation thereof causes each piston to reciprocate between the top dead centre (TDC) and the bottom dead centre (BDC). The reciprocating movement allows a compression action to be provided by each of the pistons 18A-B, wherein the compression action can be employed to pressurize a refrigerant flowing through the fixed displacement swash plate type compressor 10.
The fixed displacement swash plate type compressor 10 comprises a shaft bore 20 arranged at a centre of the swash plate 14 and cylinder block 30A-B, wherein the shaft bore 20 is operable to receive a driveshaft 22 therein. The shaft bore 20 is a through-hole made at a centre (along the axis of rotation) of the swash plate 14, cylinder block 30A-B. The shaft bore 20 is operable to receive the driveshaft 22 therein. Furthermore, the driveshaft 22 is a solid, cylindrical component that is fixedly coupled to the swash plate 14 via the shaft bore 20. The driveshaft 22 supports the swash plate 14 thereon. It will be appreciated that a diameter of the shaft bore 20 will correspond to a diameter of the driveshaft 22. Furthermore, in operation of the fixed displacement swash plate type compressor 10, the driveshaft 22 is made to rotate by providing torque thereto, such as, by an external source (for example, a belt driven by engine pulley). Consequently, the swash plate 14 that is fixedly coupled to the driveshaft 22 is made to rotate. Consequently, the pistons 18A-B coupled to each of the plurality of cylindrical bores of the cylinder block 30A-B reciprocate. Thus, the rotation of the driveshaft 22 at the centre of the swash plate 14 enables pressurization (or compression) of the refrigerant by the fixed displacement swash plate type compressor 10. However, such a
8

rotation of the driveshaft 22 within the shaft bore 20 may generate friction between an inner surface of the shaft bore 20 and an external surface of the driveshaft 22. In such an instance, to reduce such friction between the driveshaft 22 and the shaft bore 20, lubrication is required to be provided between the corresponding surfaces thereof.
The fixed displacement swash plate type compressor 10 comprises a plurality of semi-cylindrical lubrication channels (shown in FIG. 4) disposed along a circumference of the shaft bore 20. The plurality of semi-cylindrical lubrication channels are elongate grooves having a substantially semi-circular cross-section, such as, a cross-section associated with an area within a range of 35 to 70% of an area of a circle having a predetermined diameter. Furthermore, the plurality of semi-cylindrical lubrication channels is disposed vertically along the internal circumference shaft bore 20 (when viewed along the shaft bore 20), wherein each semi-cylindrical lubrication channel is equidistant from adjacent semi-cylindrical lubrication channels. In one example, the fixed displacement swash plate type compressor 10 comprises one or more, semi-cylindrical lubrication channels disposed along the circumference of the shaft bore 20. The plurality of semi-cylindrical lubrication channels allows flow of a lubricant therein, to provide lubrication between the driveshaft 22 and the shaft bore 20. In operation of the fixed displacement swash plate type compressor 10, a lubricant, such as oil, is allowed to flow in a direction parallel to the driveshaft 22 into each of the plurality of semi-cylindrical lubrication channels. Furthermore, during rotation of the driveshaft 22 within the shaft bore 20, the lubricant flowing within each of the plurality of semi-cylindrical lubrication channels is operable to contact the internal surface of the shaft bore 20 and the external surface of the driveshaft 22 respectively, thereby, reducing friction generated there between (due to rotation of the driveshaft 22). Furthermore, such a flow of the lubricant enables to reduce heat generated due to friction between the
9

driveshaft 22 and the shaft bore 20 and/or the between the driveshaft 22 and surrounding space within the fixed displacement swash plate type compressor 10. Thus, the plurality of semi-cylindrical lubrication channels enables to reduce the friction as well as temperature within the fixed displacement swash plate type compressor 10, thereby, minimizing damage associated therewith. Consequently, an operating life of the fixed displacement swash plate type compressor 10 is increased.
The fixed displacement swash plate type compressor 10 comprises at least one bush bearing 24A-B arranged along the driveshaft 22, wherein the at least one cylinder block 30A-B comprises an annular groove 26A-B respectively in fluidic communication with the plurality of semi-cylindrical lubrication channels. For example, the bush bearing 24Awith annular groove 26A is arranged along the driveshaft 22; and the bush bearing 24Bwith the annular groove 26B is arranged along the driveshaft 22. The bush bearings 24A-B are fabricated as hollow, cylindrical components having an internal diameter substantially same (to within 1%) as the external diameter of the driveshaft 22. Furthermore, the bush bearings 24A-B are operable to support the rotating driveshaft 22 (such as, radial loads produced by rotation of the driveshaft 22) and reduce a friction between the driveshaft 22 and the shaft bore 20 above and below the swash plate 14, during operation of the fixed displacement swash plate type compressor 10.
Furthermore, the cylinder block 30A-B comprise the annular grooves 26A-B respectively implemented as grooves extending from an internal surface of each of the cylinder block 30A-B, along a circumference thereof. Optionally, a size of the annular groove 26A-B of the cylinder block 30A-B is dependent upon a size of the bush bearing 24A-B. It will be appreciated that a surface of the annular groove 26A-B facing the driveshaft 22 will be coplanar with an internal surface of the bush
10

bearing 24A-B respectively. However, a depth of the annular groove 26A-B can vary, such as, depending on an amount of lubricant that is required to reduce the friction between the bush bearings 24A-B and the driveshaft 22. In such an instance, the depth of the annular groove 26A-B can be increased with an increase in the amount of the lubricant and/or rotational speed of the driveshaft 22 during operation of the fixed displacement swash plate type compressor 10. For example, the annular grooves 26A-B can be associated with a depth that is same as the thickness of the bush bearings 24A-B. Alternatively, as shown, the annular grooves 26A-B can be associated with a depth more than the thickness of the bush bearings 24A-B.
Optionally, a position of the annular groove 26A-B of the cylinder block
30A-B is dependent upon at least one of: a number of the semi-
cylindrical lubrication channels, and/or a cross sectional area of each
semi-cylindrical channel of the plurality of semi-cylindrical channels. It
will be appreciated that with an increase in rotational speed of the
driveshaft 22, an increased number of the semi-cylindrical lubrication
channels will be required to reduce friction and temperature between
the driveshaft 22 and the shaft bore 20. Such an increase in the
number of the semi-cylindrical lubrication channels will increase a
quantity of flow of the lubricant to the annular grooves 26A-B. In such
an instance, the annular grooves 26A-B can be positioned farther away
from the end of the plurality of semi-cylindrical lubrication channels to
enable reliable catchment of the high amount of lubricant by the
annular grooves 26A-B. Conversely, if the number of the semi-
cylindrical lubrication channels is less, the annular grooves 26A-B of the cylinder block 30A-B respectively can be positioned closer towards the end of the plurality of semi-cylindrical lubrication channels. For example, if there are 8 semi-cylindrical lubrication channels, the annular grooves 26A-B can be positioned closer to the end of the semi-cylindrical lubrication channels as compared to when there are 12 (or
11

more) semi-cylindrical lubricant channels along the shaft bore 20.
Similarly, with an increase in the cross-sectional area of each semi-
cylindrical channel, the quantity of flow of the lubricant to the annular
grooves 26A-B will increase. Consequently, to provide reliable
catchment of the high amount of lubricant by the annular grooves 26A-B, the annular grooves 26A-B are placed farther away from the end of the plurality of semi-cylindrical lubrication channels. For example, when the cross-sectional area of each semi-cylindrical channel is 1 mm2, the annular grooves 26A-B are placed farther away from the end of the plurality of semi-cylindrical lubrication channels as compared to when the cross sectional area is 0.5 mm2.
The annular grooves 26A-B of the cylinder block 30A-B respectively allow flow of the lubricant to or from the plurality of semi-cylindrical lubrication channels, to provide lubrication between the driveshaft 22 and the bush bearings 24A-B. In operation of the fixed displacement swash plate type compressor 10, the lubricant flows from a top of the fixed displacement swash plate type compressor 10 (when viewed along the shaft bore 20) and along the direction of the driveshaft 22. Subsequently, the lubricant is operable to flow into the annular groove 26A of the cylinder block 30A, wherein the lubricant is temporarily stored. Furthermore, the lubricant within the annular groove 26A reduces friction and temperature between the rotating driveshaft 22 and the bush bearing 24A. Thereafter, as the annular groove 26A is in fluidic communication with the plurality of semi-cylindrical lubrication channels, the lubricant flows into the plurality of semi-cylindrical lubrication channels wherein the lubricant reduces friction and temperature between the driveshaft 22 and the portion of the shaft bore 20 corresponding to the swash plate 14.
Subsequently, as the plurality of semi-cylindrical lubrication channels is in fluidic communication with the annular groove 26B of the cylinder
12

block 30B, the lubricant flows into the annular groove 26B from the
plurality of semi-cylindrical lubrication channels. The lubricant within
the annular groove 26B reduces friction and temperature between the
rotating driveshaft 22 and the bush bearing 24B. Thus, it will be
appreciated that the flow of the lubricant reduces the friction and
temperature between the rotating driveshaft 22 and various
components of the fixed displacement swash plate type compressor 10.
Thus, the flow of the lubricant increases efficiency, reliability and
longevity of the fixed displacement swash plate type compressor 10
(and consequently, the refrigerant system wherein the fixed
displacement swash plate type compressor 10 is implemented). Furthermore, the flow of the lubricant removes contaminants like solidified lubricant, dust, sludge and so forth that may get collected on the driveshaft 22 during operation of the fixed displacement swash plate type compressor 10, thereby, reducing breakdown and requirement of frequent servicing of the fixed displacement swash plate type compressor 10. Therefore, the efficiency, reliability and longevity of the fixed displacement swash plate type compressor 10 (and consequently, the refrigerant system wherein the fixed displacement swash plate type compressor 10 is incorporated) are further improved.
Optionally, the fixed displacement swash plate type compressor 10 further comprises a thrust bearing 28A-B arranged along each side of the swash plate 14. For example, as shown, the thrust bearing 28A is arranged above the swash plate 14 in between the bush bearing 24A and the swash plate 14; and the thrust bearing 28B is arranged below the swash plate 14 in between the swash plate 14and the bush bearing 24B. In such an example, the thrust bearings 28A-B reduce axial loads produced by rotation of the driveshaft 22. Moreover, in operation, lubricant from the annular groove 26A-B is operable to flow into the plurality of semi-cylindrical lubrication channels via the thrust bearing 28A-B. In such an instance, the lubricant flowing between the thrust
13

bearing 28A-B and the driveshaft 22 reduces friction and temperature there between. Thus, the reduction in friction and temperature between the thrust bearings 28A-B and the rotating driveshaft 22 due to flow of the lubricant there between further enables efficient and reliable operation of the fixed displacement swash plate type compressor 10, while increasing the operating life thereof. More optionally, the thrust bearings 28A-B can comprise one or more radial and/or axial lubrication passages for flow of the lubricant there through.
Referring to FIG. 2, there is shown a schematic illustration of the fixed displacement swash plate type compressor 10, in accordance with another embodiment of the present disclosure. The fixed displacement swash plate type compressor 10 comprises lubrication grooves 40A-B (shown in FIG. 5) disposed along the circumference of the shaft bore 20. For example, the lubrication grooves 40A-B can be implemented to have a semi-circular cross-section, a rectangular cross-section, and so forth. Furthermore, the lubrication grooves 40A-B can extend helically along the inner circumference of the shaft bore 20, such that a length of each of the lubrication grooves 40A-B between distal ends thereof corresponds to a length of the at least one bush bearing 24A-B arranged along the driveshaft 22.
Referring to FIG. 3, there is shown a schematic illustration of the fixed displacement swash plate type compressor 10, in accordance with yet another embodiment of the present disclosure. The fixed displacement swash plate type compressor 10 comprises vertical lubrication pockets 42A-B disposed along the circumference of the shaft bore 20. For example, the vertical lubrication pockets 42A-B can be semi-cylindrical lubrication pockets disposed vertically along the shaft bore 20, such that the lubrication pockets 42A-B allow flow of lubricant along the shaft bore 20. Such vertical lubrication pockets 42A-B enable convenient flow of lubricant into, and out of the annular grooves 26A-B
14

of the bush bearings 24A-B respectively. As shown, the lubrication pockets 42A-B are arranged collinearly with a gap there between. Alternatively, the lubrication pockets 42A-B can be arranged without the gap, such that the lubrication pockets 42A-B form a single lubrication pocket extending along a length of the shaft bore 20.
Referring to FIG. 4, there is shown a perspective view of a cylinder block 30 (such as the cylinder block 30A-B of FIG. 1) and a bush bearing 32 (such as the bush bearings 24A-B of FIG. 1), in accordance with an embodiment of the present disclosure. As shown, cylinder block 30 comprises a plurality of cylindrical bores 34A-C arranged radially along the cylinder block 30. Furthermore, the cylinder block 30 comprises a shaft bore 36 wherein a plurality of semi-cylindrical lubrication channels 38A-B is disposed along a circumference of the shaft bore 36. Furthermore, the bush bearing 32 is arranged such that a central axis of the bush bearing 32 coincides with an axis of rotation of the cylinder block 30.
Referring to FIG. 5, there is shown a perspective view of a cylinder block 30 (such as the cylinder block 30A-B of FIG. 2) and the bush bearing 32, in accordance with an embodiment of the present disclosure. The cylinder block 30 comprises a shaft bore 44, wherein the shaft bore 44 comprises a lubrication grooves 46 disposed helically along a circumference of the shaft bore 44.
Referring to FIG. 6, there is shown an exploded view of the cylinder block 30 and the bush bearing 32 of FIG. 4, in accordance with an embodiment of the present disclosure.
Referring to FIG. 7, there is shown an exploded view of the cylinder block 30 and the bush bearing 32 of FIG. 5, in accordance with an embodiment of the present disclosure.
15

The fixed displacement swash plate type compressor comprises the
plurality of semi-cylindrical lubrication channels disposed along the
circumference of the shaft bore. The plurality of semi-cylindrical
lubrication channels are used to provide flow of a lubricant between the
driveshaft and the shaft bore. It will be appreciated that such a flow of
the lubricant reduces friction and temperature between the rotating
driveshaft and the shaft bore, thereby preventing damage to the
driveshaft and the shaft bore. Such a prevention of damage to the
driveshaft and the shaft bore enables efficient and reliable operation of
the fixed displacement swash plate type compressor. Furthermore,
providing the flow of the lubricant by using the plurality of semi-
cylindrical lubrication channels eliminates a requirement of a lubrication
arrangement to be implemented within the fixed displacement swash
plate type compressor, thus reducing a weight, size and manufacturing
cost thereof. Moreover, the fixed displacement swash plate type
compressor comprises the at least one bush bearing having the annular
groove, in fluidic communication with the plurality of semi-cylindrical
lubrication channels. It will be appreciated that using the bush bearing
allows simple, convenient and cost-effective reduction in radial loads on
the driveshaft due to rotation thereof. Furthermore, the lubricant
allowed to flow into the annular groove of the at least one cylinder block reduces friction and temperature between the bush bearing and the rotating driveshaft, thereby, reducing damage, requirement of frequent servicing and/or replacement. Therefore, the flow of lubricant between the driveshaft and the bush bearing by using the annular groove further increases reliability, efficiency and longevity of the fixed displacement swash plate type compressor. Thus, the fixed displacement swash plate type compressor enables reliable and efficient pressurization of the refrigerant flowing through automobile cooling systems implementing the fixed displacement swash plate type compressor therein, while
16

substantially overcoming problems associated with conventional compressors used in automobile cooling systems.
Modifications to embodiments of the invention described in the foregoing are possible without departing from the scope of the invention as defined by the accompanying claims. Expressions such as "including", "comprising", "incorporating", "consisting of", "have", "is" used to describe and claim the present invention are intended to be construed in a non-exclusive manner, namely allowing for items, components or elements not explicitly described also to be present. Reference to the singular is also to be construed to relate to the plural. Numerals included within parentheses in the accompanying claims are intended to assist understanding of the claims and should not be construed in any way to limit subject matter claimed by these claims.

We Claim:

A fixed displacement swash plate type compressor comprising:
- a cylinder block comprising a plurality of cylindrical bores arranged radially along the cylinder block;
- a piston coupled to each of the plurality of cylindrical bores, wherein the pistons are operable to reciprocate in response to movement of the swash plate;
- a shaft bore arranged at a centre of the swash plate, and cylinder blocks wherein the shaft bore is operable to receive a driveshaft therein;
- a plurality of semi-cylindrical lubrication channels disposed along a circumference of the shaft bore, and
- at least one bush bearing arranged along the driveshaft, wherein the at least one cylinder block comprises an annular groove in fluidic communication with the plurality of semi-cylindrical lubrication channels;
wherein the plurality of semi-cylindrical lubrication channels allows flow of a lubricant therein, to provide lubrication between the driveshaft and the shaft bore,
and wherein the annular groove of the cylinder block allows flow of the lubricant to or from the plurality of semi-cylindrical lubrication channels, to provide lubrication between the driveshaft and the bush bearing.
2. A fixed displacement swash plate type compressor as claimed in
claim 1, wherein the pistons are coupled to the plurality of cylindrical
bores.

3. A fixed displacement swash plate type compressor as claimed in claim 2, wherein a position of the annular groove of the cylinder block is dependent upon at least one of: a number of the semi-cylindrical lubrication channels, and/or a cross sectional area of each semi-cylindrical channel of the plurality of semi-cylindrical channels.
4. A fixed displacement swash plate type compressor as claimed in claim 2, wherein a size of the annular groove of the cylinder block is dependent upon a size of the bush bearing.
5. A fixed displacement swash plate type compressor as claimed in claim 1, wherein the plurality of semi-cylindrical lubrication channels is in fluidic communication with a lubricant source.