JPH10159718A - Reciprocating piston compressor - Google Patents

Abstract

PROBLEM TO BE SOLVED: To easily machine and assemble with high accuracy a divided connecting rod of a reciprocating piston compressor used for a home refrigerator and to prevent a decrease in efficiency and an increase in noise and vibration caused by an increase in rotational load produced by that the axis of the large end hole skews the axis of the small end hole. SOLUTION: A locking projection 61 of a small end part 50 whose tip end is shaped like a semi-sphere or a cone is fitted in a fixing groove 63 of a large end part 52 whose bottom end is orthogonal to a large end hole 53 and is shaped like a semi-sphere or a cone and a locking pin 65 is inserted into a fixing hole 55 and a locking hole 59 to form a connecting rod 19, which can eliminate the condition that the axis of the large end hole 53 skews the axis of the small end hole 51 and produce the stable movement of the connecting rod 19.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a relatively small reciprocating piston compressor used in a home refrigerator or the like.

[0002]

2. Description of the Related Art In recent years, reciprocating piston compressors have been downsized,
Various improvements have been made from the viewpoint of simplifying assembly. There are also high demands from the market for higher efficiency and lower noise.

A conventional reciprocating piston compressor is disclosed in Japanese Patent Application Laid-Open No. 4-164174 and Japanese Patent Publication No. 5-84837.

A conventional reciprocating piston compressor disclosed in Japanese Patent Publication No. 5-84837 will be described below with reference to FIGS. 16, 17 and 18.

FIG. 16 is a longitudinal sectional view of a conventional reciprocating piston compressor, FIG. 17 is an enlarged view of FIG. 16, and an exploded view of a connecting rod and a piston before assembling the reciprocating piston compressor, and FIG. FIG. 3 is an exploded plan view of a large end and a small end.

In FIGS. 16, 17 and 18, the motor / compressor unit 1 is supported in a housing 3 by a spring 2. The crankcase 4 serves as a support for mounting the stator 5 of the motor, and includes a bearing 6 for supporting a crankshaft 7 connecting the rotor 8 of the motor. The crankcase 4 has a cylinder 9 in which a piston 10 reciprocates. An eccentric shaft 11 is provided at an upper end of the crankshaft 7. A valve plate 17 and a cylinder head 18 which can be manufactured by a known method are attached to the cylinder 9 at the end of the cylinder 9 and on the side opposite to the crankshaft 7.
The connecting rod 19 is composed of a small end 20 and a large end 30,
The piston 10 and the eccentric shaft 11 of the crankshaft 7 are connected.

The small end 20 of the connecting rod 19 comprises a small end hole 21 and a long first projection 22 extending radially from the small end hole 21. The first projection 22 defines an arm portion of the connecting rod 19. The small end hole 21 is connected to the piston 10 by the piston pin 15.

The large end 30 of the connecting rod 19 is
3, a large end hole 31 having a short second protrusion 32 extending in the radial direction, and the large end hole 31 into which the eccentric shaft 11 of the crankshaft 7 is inserted.

The groove 33 of the large end hole 31 is
Opposing and parallel surfaces 34 formed inside the
And two internal second end faces 35 formed in a V-shape, and a vertical depression 36 is provided at the top of the second end face 35. A surface 24 and two V-shaped first end surfaces 25 are formed at the end 27 of the first protrusion 22.
The end faces 25 are configured to completely contact the second end faces 35 of the grooves 33, respectively.

The operation of the conventional reciprocating piston compressor configured as described above will be described below.

With the crankshaft 7 inserted into the bearing 6 of the crankcase 4, the large end hole 31 of the large end 30 of the connecting rod 19 is inserted into the eccentric shaft 11, and the piston pin is inserted into the small end hole 21. The piston 10 and the small end portion 20 connected by inserting the piston 15 are inserted from the counter crankshaft of the cylinder 9.

Thereafter, the end 27 of the first projection 22 of the small end 20 is fitted into the groove 33 of the second projection 32 of the large end 30, and the surface 24, the first end face 25 of the first projection 22 and The surface 34 of the groove 33 of the first protrusion 32 and the second end surface 35 are respectively brought into contact with each other and fixed by a method such as welding. The connecting rod 19 to which the large end 30 and the small end 20 are fixed is connected to the crankshaft 7.
Is converted into reciprocating motion of the piston 10 to transmit a force, thereby compressing the gas in the cylinder 9.

[0013]

However, in the above-mentioned conventional structure, the joining of the small end 20 and the large end 30 of the connecting rod 19 is performed by fitting the end 27 into the groove 33. Face 24, first end face 25 and groove 33
The surface 34 and the second end surface 35 need to be subjected to very high-precision surface finishing, and have a drawback that processing is difficult.

Further, the above-mentioned conventional construction is such that the axis of the hole of the large end hole 31 is parallel to the surface 34 of the groove 33 and the second end surface 35, or the axis of the small end hole 21 and the end of the end 27. If the plane 24 and the first end face 25 are slightly out of parallel with each other, the axes of the large end hole section 31 and the small end hole section 21 of the connecting rod 19 are twisted, and when a force is applied in the vertical direction, there is no defined end face. The fixing of the direction becomes very unstable, and the connecting rod 19 twists on the crankshaft 7 and the piston pin 15 to increase the rotational load of the compressor, resulting in increased noise or vibration and reduced efficiency. .

The present invention solves the conventional problems.
An object of the present invention is to provide a reciprocating piston compressor having high accuracy, easy processing and assembly, high efficiency, low noise and low vibration.

Further, the above-mentioned conventional structure is different from the connecting rod 19 shown in FIG.
The lubrication of the joint between the small end 20 and the large end 30 depends on the mist-like oil in the housing 3, and there is no active lubrication, resulting in a decrease in reliability due to metal wear at the joint. was there.

Another object of the present invention is to positively lubricate the joint of the connecting rod 19 to improve reliability.

[0018]

In order to achieve this object, the present invention provides a small end portion connected to a piston by a small end hole by a piston pin, and a small end portion connected to an eccentric shaft of a crankshaft by a large end hole. A reciprocating piston compressor including a connecting rod having a large end, wherein the large end of the connecting rod has a cylindrical circular hole and a protrusion having a fixing hole communicating with the circular hole, and the circular hole has a bottom shape. It is hemispherical or substantially conical, and is provided at a depth that does not penetrate the large end hole from the end surface of the projection toward the center of the large end hole, and the small end has a cylindrical rod portion that is long in the radial direction. The rod portion has a locking hole at the end and a locking portion having a hemispherical or substantially conical shape at the end. The locking portion is loosely fitted or lightly press-fitted into the circular hole portion of the projection. By inserting the locking pin through the fixing hole and the locking hole, the locking portion and the circular hole are locked, The small end hole and big end of the small end of the Nroddo arrangement of geometric axis of the large end hole is to keep on the same plane.

As a result, processing and assembly of the reciprocating piston compressor can be performed with high accuracy, and high efficiency, low noise and low vibration can be achieved.

Further, a flat portion is provided in the cylindrical locking portion of the rod portion and the cylindrical hole portion of the projection.

As a result, the reciprocating piston compressor can be easily assembled, the behavior of the locking portion around the axis can be regulated, the connecting rod behavior can be stabilized, and the efficiency can be prevented from being lowered and noise and vibration can be prevented from increasing.

Further, an oil hole for communicating the top of the circular hole with the large end hole is provided, and the oil hole is communicated with the oil groove of the eccentric shaft of the crankshaft.

As a result, active lubrication can be performed at the joint between the small end and the large end of the connecting rod, metal wear can be reduced, and the reliability of the reciprocating piston compressor can be improved.

Further, a locking groove is provided in a cylindrical locking portion of the rod portion and a fixing groove is provided in a flat portion of the projection portion, and the locking portion of the rod portion is loosely fitted or lightly pressed into a circular hole portion of the projection portion. At the same time, the locking portion and the circular hole portion are locked by fitting the fixing plate by communicating with the locking groove from the fixing groove, and the small end hole at the small end portion and the large end hole at the large end portion of the connecting rod. Are maintained on the same plane.

As a result, the small end and the large end of the connecting rod can be firmly fixed to each other, the connecting rod behavior can be stabilized, and a reduction in efficiency and an increase in noise and vibration can be prevented.

Further, a holding portion having an auxiliary flat portion to be joined to the end surface portion of the projection portion when fitted to the circular hole portion is provided between the rod portion and the locking portion.

As a result, the assemblability is improved, the load acting on the auxiliary plane portion and the end surface portion is reduced, the behavior of the connecting rod is stabilized, and a reduction in efficiency, noise and vibration can be prevented.

Also, a second locking projection having a locking end surface parallel to the cylindrical axis of the small end hole is provided between the rod portion and the locking portion, and the large end projection is provided on the large end projection. The fixed end face parallel to the cylindrical axis direction is provided, and when the small end and the large end are connected, the locking end face and the fixed end face are joined to define the fitting position of the small end and the large end.

As a result, it is possible to assemble with high accuracy, to stabilize the behavior of the connecting rod, and to prevent a decrease in efficiency and an increase in noise and vibration.

[0030]

DESCRIPTION OF THE PREFERRED EMBODIMENTS The present invention comprises a connecting rod having a small end connected to a piston by a small end hole by a piston pin, and a large end connected to an eccentric shaft of a crankshaft by a large end hole. A reciprocating piston compressor, in which a large end of a connecting rod has a cylindrical hole and a protrusion having a fixing hole communicating therewith, and the hole has a hemispherical or substantially conical bottom shape. , From the end face of the projection to the center of the large end hole at a depth that does not penetrate the large end hole, the small end has a cylindrical rod portion that is long in the radial direction, and the rod portion is an end portion. The locking hole and the tip constitute a hemispherical or substantially conical locking part,
The locking portion is loosely fitted or lightly press-fitted into the circular hole portion of the protrusion, and the locking portion and the circular hole portion are locked by inserting the locking pin through communication between the fixing hole and the locking hole, The arrangement of the geometric axes of the small end hole at the small end of the connecting rod and the large end hole at the large end is maintained on the same plane.

When a load is applied to the connecting rod from all directions during operation of the compressor, the tip of the hemispherical or substantially conical locking portion at the small end is replaced with the hemispherical shape of the circular hole at the large end. Alternatively, surface contact occurs at the substantially conical bottom surface, and the load is dispersed, so that concentrated load at the edge portion or the like is not received. Also, when connecting the large end to the small end, the tip of the locking portion of the large end has a hemispherical or substantially conical shape, and has no edge portion so that the circular hole of the small end can be easily formed. Can be fitted into Furthermore, when the locking pin is inserted into the locking hole at the small end and the fixing hole at the large end, and the two are connected, the locking pin is self-flexible so that the small pin at the small end and the large end are connected. The small end of the large end hole of the portion absorbs a slight deflection of the axis, and the small end hole and the large end hole are self-corrected so that their axes coincide with each other, thereby stabilizing the operation. Further, since the rod portion at the small end and the circular hole at the large end are cylindrical, high-precision machining can be easily performed.

This prevents an increase in rotational load due to twisting or twisting during assembly or operation of the compressor.

Further, a flat portion is provided in the cylindrical locking portion of the rod portion and the cylindrical hole portion of the projection.

When the locking portion at the small end is fitted into the circular hole at the large end, the flat portion of the locking portion and the flat portion of the circular hole are fitted and positioned. The fixing hole of the stop hole and the circular hole almost match, making it easy to assemble without aligning the hole when inserting the locking pin, and preventing the locking part from moving around the axis. Thus, the behavior of the connecting rod is stabilized.

Further, an oil hole for communicating the top of the circular hole with the large end hole is provided, and the oil hole is communicated with the oil groove of the eccentric shaft of the crankshaft.

During the operation of the compressor, oil is actively supplied to the small-end locking portion and the large-end circular hole, thereby reducing wear due to metal contact.

Further, a locking groove is provided in the cylindrical locking portion of the rod portion and a fixing groove is provided in the flat portion of the projection portion, and the locking portion of the rod portion is loosely fitted or lightly pressed into the circular hole portion of the projection portion. At the same time, the locking portion and the circular hole portion are locked by fitting the fixing plate by communicating with the locking groove from the fixing groove, and the small end hole at the small end portion and the large end hole at the large end portion of the connecting rod. Are maintained on the same plane.

Since the large end and the small end are firmly fixed by the fixing plate, the behavior of the connecting rod is stabilized.

Further, a holding portion having an auxiliary flat portion to be joined to the end surface portion of the projection portion at the time of fitting with the circular hole portion is provided between the rod portion and the locking portion.

Then, the margin for fitting the locking portion into the circular hole is defined, the assemblability is improved, and the load applied to the joint surface between the end surface and the auxiliary flat portion is dispersed, so that the connecting rod behavior is stabilized. It will be.

Further, a second locking projection having a locking end surface parallel to the cylindrical axis direction of the small end hole is provided between the rod portion and the locking portion, and the large end projection is provided on the large end projection. The fixed end face parallel to the cylindrical axis direction is provided, and when the small end and the large end are connected, the locking end face and the fixed end face are joined to define the fitting position of the small end and the large end.

When fitting the locking portion into the circular hole,
By joining the locking end face and the fixed end face, the position around the axis of the locking part cylindrical shape and the fitting allowance are specified, and there is no need to finely adjust the hole position when inserting the locking pin into the locking hole and the fixing hole. In addition, the assembling can be easily performed, and since the locking end face and the fixed end face are fixed around the axis of the locking portion of the connecting rod and in the left-right direction, the connecting rod behavior is stabilized.

[0043]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of a reciprocating piston compressor according to the present invention will be described below with reference to the drawings. The same components as those in the related art are denoted by the same reference numerals, and detailed description is omitted.

(Embodiment 1) FIG. 1 is a longitudinal sectional view of a reciprocating piston compressor according to Embodiment 1 of the present invention. FIG. 2 shows FIG.
3 is an exploded view of a connecting rod and a piston before assembling a reciprocating piston compressor, FIG. 3 is a plan view of the connecting rod of FIG. 1 before assembling, and FIG. FIG.

In FIG. 1, reference numeral 19 denotes a connecting rod, one end of which is connected to the piston 10 by a piston 15 which is loosely fitted in the small end hole 51 of the small end 50, and the other end of which is the large end hole 5 of the large end 52.
At 3, the crankshaft 7 is loosely fitted and connected to the eccentric shaft 11.

In FIG. 2, the piston 10, the piston pin 15 and the small end 50 are connected to the counter crankshaft 7 of the cylinder 9.
The large end 52 of the connecting rod 19 is inserted into the eccentric shaft 11 of the crankshaft 7 from above vertically.

The large end 52 of the connecting rod 19 has a circular hole 54 in the circumferential direction and a projection 56 having a fixing hole 55 passing through the circular hole 54. The circular hole 54 is
It is perpendicular to the large end hole 53 and is machined to a depth that does not penetrate the large end hole 53 from the end face 57 of the projection 56. The small end portion 50 has a rod portion 58 perpendicular to the small end hole 51 extending in the circumferential direction, and has a locking portion 60 having a locking hole 59 at the tip.

In FIGS. 3 and 4, reference numeral 61 denotes a leading end of the locking portion 60, which is a locking projection formed into a hemispherical or substantially conical shape. Reference numeral 62 denotes a locking top of the locking projection 61, which is rounded. Reference numeral 63 denotes a fixing groove formed into a hemispherical or substantially conical shape of the circular hole 54, and reference numeral 64 denotes a groove top of the fixing groove.

After the locking portion 60 is inserted into the circular hole 54, the locking pin 65 is inserted into the locking hole 59 of the locking portion 60 of the small end 50 from the fixing hole 55 of the projection 56 of the large end 52. By doing so, the small end 50 and the large end 52 of the connecting rod 19 are connected and fixed.

The operation of the above configuration will be described below. The locking portion 60, which is a connecting portion of the small end portion 50 of the circular hole portion 54, has a cylindrical shape, so that processing is simple and dimensional accuracy is easily obtained.

When the engaging portion 60 is loosely fitted or lightly press-fitted into the circular hole portion 54, the engaging projection 62, which is the tip of the engaging portion 60, is provided.
Is hemispherical or substantially conical, so that it can be smoothly fitted into the circular hole 54.

Since both the locking portion 60 and the circular hole 54 are cylindrical, they can be slightly swung around the cylindrical axis, and the cylindrical shafts of the small end hole 51 and the large end hole 53 are twisted during assembly. It is no longer difficult to enter.

After fitting the locking portion 60 into the circular hole portion 54, the locking top portion 62 is rounded, so that the locking top portion 62 is fitted while leaving a slight clearance with the groove top portion 64. At this time, a small amount of assembling oil is retained in the clearance.

Next, when the locking pin 65 is inserted into the locking hole 59 and the fixing hole 55, the locking pin 65 is slightly deformed by its own deformation and is slightly twisted when fitted.
And the torsion of the cylindrical shaft of the large end hole 53 is corrected in the same axial direction, and the locking portion 60 is fixed to the circular hole portion 54.

Further, when the cylindrical shaft of the small end hole 51 and the large end hole 53 is twisted during the operation of the compressor due to a compression load or the like, the locking pin 65 is slightly deformed by the load and the compressor is deformed. Stabilizes where mechanical balance is good.

Further, since the connecting rod 19 converts the rotational behavior into the translational behavior, during operation of the compressor, the large end 52 is moved to the small end 50 via the locking portion 60 as shown in FIG. Forces in all directions, such as front and rear, left and right, and slightly, up and down as shown in FIG. 4 act on the locking portion 60 and the circular hole 54. At this time, since the tip of the locking portion 60 is processed into a hemispherical shape or a substantially conical shape, a surface facing in all directions is formed. Therefore, the cylindrical shafts of the small end portion 50 and the large end portion 52 are stabilized in the same direction during the operation of the compressor, and the rotational force of the crankshaft 7 is almost completely eliminated at the locking portion 60. 15 can be transmitted.

As described above, in the reciprocating piston compressor of this embodiment, the large end 52 of the connecting rod 19 is
4 and a protrusion 56 having a fixing hole 55 communicating therewith. The bottom of the circular hole 54 is a hemispherical or substantially conical shape, and the center of the large end hole 53 extends from the end face 57 of the protrusion 56. The small end 50 is provided at a depth that does not penetrate the large end hole 53.
Has a cylindrical rod portion 58 that is long in the radial direction. The rod portion 58 has a locking hole 59 at the end and a locking portion 60 having a hemispherical or substantially conical shape at the tip. The locking portion 60 and the circular hole 54 are inserted by loosely fitting or lightly press-fitting the portion 60 into the circular hole 54 of the protrusion 56 and inserting the locking pin 65 through the fixing hole 55 and the locking hole 59. And the geometric axes of the small end hole 51 of the small end portion 50 of the connecting rod 19 and the large end hole 53 of the large end portion 52 are maintained on the same plane. Is easy and the small end hole 5
1 and the large end hole 53, the rotational load increases due to the torsion of the cylindrical shaft, the efficiency decreases, and the small end hole 51 and the piston pin 1
5, the large end hole 53 and the eccentric shaft 11, the locking portion 60 and the circular hole portion 5.
It is possible to prevent an increase in noise and vibration due to abnormal prying such as No. 4.

(Embodiment 2) FIG. 5 is a plan view of a connecting rod of a reciprocating piston compressor according to Embodiment 2 of the present invention before assembling, and FIG. 6 is a large end portion A before assembling viewed from the arrow A in FIG. Arrow view. FIG. 7 is a partial longitudinal sectional view when the connecting rod is assembled.
The same components as those in the first embodiment are denoted by the same reference numerals, and detailed description is omitted.

In FIGS. 5, 6 and 7, reference numeral 70 denotes a fixed plane portion provided in the cylindrical axis direction of the cylindrical hole portion 54 of the large end portion 52. Since the fixing groove 63 is the fixing flat part 70, it is machined so that the diameter of one step is smaller than the cylindrical diameter of the circular hole 54. Reference numeral 71 denotes a locking flat portion provided in the cylindrical axis direction of the cylindrical locking portion 60 of the small end portion 50. Fixed groove 6
3, the locking projection 61 is the locking flat portion 71,
It is machined so that the diameter of one step is smaller than the cylindrical diameter of the locking portion 60.

The operation of the above configuration will be described below. When fitting the locking portion 60 into the circular hole portion 54,
The locking flat portion 71 and the fixing flat portion 70 serve as a kind of positioning guider, and the locking hole 59 and the fixing hole 55, which have been slightly displaced at the same time as the fitting, are accurately aligned, and the locking pin 65 can be easily fixed. Can be inserted.

Further, the behavior of the engaging portion 60 around the axis is regulated by the joining of the engaging flat surface 70 and the fixed flat surface 71, and the behavior of the connecting rod 19 is stabilized.

As described above, in the reciprocating piston compressor of this embodiment, the locking end face portion 71 is provided on the cylindrical locking portion 60 of the rod portion 58, and is fixed to the cylindrical hole portion 54 of the projection portion 56. Since the flat portion 70 is provided, the connecting rod 19
At the time of assembling, the position of the locking hole 59 and the fixing hole 55 are accurately matched at the same time when the locking portion 60 is fitted into the circular hole portion 54, the locking pin 65 can be easily inserted, and the assembly can be facilitated.

Further, the behavior around the axis of the locking portion 60 is regulated, and the behavior of the connecting rod can be stabilized.

In this embodiment, the locking flat portion 71
The fixing flat portion 70 is provided with the fixing hole 5.
5, the same effect can be obtained regardless of where these flat portions are located around the cylindrical shape.

(Embodiment 3) FIG. 8 is a partial longitudinal sectional view of a connecting rod and an eccentric shaft during a suction stroke of a reciprocating piston compressor according to a third embodiment of the present invention, and FIG. 9 is a connecting rod and an eccentric shaft during a compression stroke. 3 is a partial vertical sectional view of FIG. The same components as those in the first embodiment are denoted by the same reference numerals, and detailed description is omitted.

8 and 9, reference numeral 75 denotes the crankshaft 7.
A first oil supply hole provided in the eccentric shaft 11 communicates with a second oil supply hole 76 provided in the eccentric shaft 11. The second oil supply hole 76 is opened at the upper end face of the eccentric shaft 11, and a horizontal oil hole 77 is provided in the radial direction from the middle of the second oil supply hole 76 and communicates with the oil groove 78 on the outer periphery of the eccentric shaft 11. ing. Horizontal oil hole 77 and oil groove 7
Reference numeral 8 is directed toward the axial center of the crankshaft 7. 79
Is a communication oil hole communicating from the groove top 64 of the fixed groove 63 to the large end hole 53.

The operation of the above configuration will be described below. The points shown in FIGS. 8 and 9 represent oil particles,
Arrows indicate the flow of oil.

During the suction stroke of the compressor, the lubricating oil (not shown) accumulated at the bottom of the housing 3 due to the centrifugal pump action of the first oil supply hole 75 of the crankshaft 7 with the rotation of the compressor. It is pushed up to the second oil supply hole 76. Then, due to the centrifugal force caused by the rotation of the eccentric shaft 11, the oil particles are guided from the second oil supply hole 76 to the oil groove 78 provided on the outer periphery of the eccentric shaft 11 via the horizontal oil hole 77. Some oil particles are discharged from above the eccentric shaft 11 into the housing 3.

Therefore, during the suction stroke of the compressor as shown in FIG. 8, since the oil groove 78 is located in the axial direction of the crankshaft 7, the oil groove 78 and the large end 52
Communicates with the communication oil hole 79 provided at the bottom. Further, the small end 50 is pulled toward the crankshaft 7 side, and the large end 52 is pulled toward the crankshaft 7 side. As a result, a slight gap is generated between the locking projection 61 and the fixing groove 63, and the oil particles that have reached the oil groove 78 by centrifugal force pass through the communication oil hole 79 without losing their inertia. It is guided to a slight gap between the locking projection 61 and the fixing groove 63.

In the compression stroke as shown in FIG. 9, the oil groove 78 and the communication oil hole 79 do not communicate with each other, and the small end 5
0, the locking protrusion 61 and the fixing groove 63
Will push each other. As a result, the oil particles guided to the gap during the suction stroke are pressed, flow backward through the locking pin 65 or the communication oil hole 79 from the slight gap, and are discharged into the housing 3 from the upper and lower portions of the eccentric shaft 11. . The oil particles guided to the oil groove 78 through the horizontal oil hole 77 are supplied as lubricating oil for the large end hole 53 and the eccentric shaft 11.

Thus, the lubricating oil is evenly supplied to the locking projections 61 and the fixing grooves 63 which are the connecting portions of the connecting rod 19, and the lubricating oil circulates, thereby acting as a cooling effect around the connecting portions. In addition, sliding loss can be reduced, and wear due to metal contact can be prevented.

As described above, the reciprocating piston compressor of this embodiment is provided with the communication oil hole 79 communicating with the large end hole 53 and the groove top 64 of the fixed groove 63, and with the oil groove 78 of the eccentric shaft 11. Since the communication oil hole 79 is made to communicate, the lubricating oil can be actively supplied to the locking projection 61 and the fixing groove 63 which are the connecting portions of the connecting rod 19. Thereby, it is possible to prevent an increase in sliding loss and wear due to metal contact.

In this embodiment, the oil groove 78 and the communication oil hole 79 communicate with each other during the suction stroke. However, the oil groove 78 and the communication oil hole 79 may communicate with each other during the other strokes or at all times, and the same effect can be obtained.

(Embodiment 4) FIG. 10 shows Embodiment 4 of the present invention.
FIG. 11 is a partial vertical cross-sectional view of the reciprocating piston compressor before assembling the connecting rod of FIG. The same components as those in the first embodiment are denoted by the same reference numerals, and detailed description is omitted.

In FIGS. 10 and 11, reference numeral 80 denotes the small end portion 5.
Locking groove 80 provided on the outer circumference of the cylindrical locking portion 60
Reference numeral 81 denotes a fixing groove provided on the projection 56 of the large end 52. The fixing groove 81 partially communicates with the circular hole 54. Reference numeral 82 denotes a fixing plate for fixing the locking portion 60 to the circular hole portion 54. The front end of the fixing plate 82 has a key portion forming a key projection.

The operation of the above configuration will be described below. When the locking portion 60 is fitted into the circular hole 54, the locking groove 80 and the fixing groove 81 overlap. Then, fixation plate 8
2 is inserted from the fixing groove 81 to the locking groove 80, and the key 83, which is the tip of the fixing plate 82, is fitted into the end face of the projection 56. As a result, the locking portion 60 is
4 and pressed against the bottom.

As a result, most of the load received by the locking projection 61 and the fixing groove 63 is received by the fixing plate 82, and the connection of the connecting rod 19 can be strengthened.
The connecting rod behavior becomes stable.

As described above, the reciprocating piston compressor of the present embodiment has the locking groove 80 on the outer periphery of the locking portion 60 of the small end 50,
A fixing groove 81 communicating with the circular hole portion 54 is provided in the projecting portion 56 of the large end portion 52, and after the locking portion 60 is fitted into the circular hole portion 54,
A fixing plate 82 having a key portion 83 at the tip is fitted from the fixing groove 81 to the locking groove 80 so as to communicate with the small end 50 and the large end 5.
2, the locking portion 60 is firmly fixed to the circular hole portion 54, and the connecting rod 1 is connected during the operation of the compressor.
Most of the load acting on 9 is supported by the fixed plate 82, and the connecting rod behavior can be stabilized.

(Embodiment 5) FIG. 12 shows Embodiment 5 of the present invention.
FIG. 13 is a partial longitudinal sectional view of the reciprocating piston compressor before assembling the connecting rod of FIG. The same components as those in the first embodiment are denoted by the same reference numerals, and detailed description is omitted.

In FIGS. 12 and 13, reference numeral 85 denotes a large end portion.
The rod portion 58 of the small end portion 50 having the auxiliary flat portion 86 having a plane opposite to the plane of the end surface portion 57 of the second protrusion 56.
And a holding portion provided between the locking portion 60 and the holding portion 60.

The operation of the above configuration will be described below. When the locking portion 60 is fitted into the circular hole portion 54, the auxiliary flat portion 86 is joined to the end face portion 57. Thereby, the fitting allowance can be defined in the circular hole portion 54 of the locking portion 60,
The connecting pin 19 can be assembled by simply inserting the locking pin 65 into the locking hole 59 and the fixing hole 55.

Further, the load received during the compression stroke of the compressor can be received by the auxiliary flat portion 86, and the behavior of the connecting rod 19 can be stabilized.

As described above, the reciprocating piston compressor according to the present embodiment has the projection 56 between the locking portion 60 and the rod portion 58.
By providing a holding portion 85 having an auxiliary plane portion 86 facing the end surface portion 57 of the locking portion 60, the circular hole portion 5 of the locking portion 60 is provided.
4 can be specified, and the connecting rod 19 can be easily formed.
Can be assembled, and the behavior of the connecting rod 19 can be stabilized by receiving the load during the compression stroke on the auxiliary plane portion.

In this embodiment, the locking projection 61 and the fixing groove 63 are provided. However, the same effect can be obtained without this.

(Embodiment 6) FIG. 14 shows Embodiment 6 of the present invention.
14 is a plan view of the reciprocating piston compressor before assembling the connecting rod, and FIG. 15 is a partial longitudinal sectional view of the connecting rod of FIG. The same components as those in the first embodiment are denoted by the same reference numerals, and detailed description is omitted.

In FIGS. 14 and 15, reference numeral 90 denotes the small end hole 5.
A second locking projection provided between the rod portion 58 and the locking portion 60 having a locking end surface 91 provided in parallel with the first cylindrical axis, and a large 92 opposed to the locking end surface 91. End hole 53
Is a fixed end surface of the protrusion 56 provided in parallel with the cylindrical axis of FIG.

The operation of the above configuration will be described below. When the locking portion 60 is fitted into the circular hole portion 54, the locking end surface 91 and the fixed end surface 92 are joined, and the locking portion 60
Since the fitting allowance and the position in the left and right direction are specified,
The positions of the locking hole 59 and the fixing hole 55 are accurately matched. Thus, the locking pin 65 can be easily inserted into the locking hole 59 and the fixing hole 55, so that the connecting rod 19 can be easily assembled.

Further, the second locking projection 91 prevents the small end 50 and the large end 52 from being displaced around the axis of the locking portion 60 or in the left-right direction during operation of the compressor. 19
Can be strengthened, and the behavior of the connecting rod 19 can be stabilized.

As described above, the reciprocating piston compressor of this embodiment has the second locking projection between the locking portion 60 and the rod portion 58, which has the locking end surface 91 parallel to the cylindrical axis of the small end hole 51. By providing a fixed end surface 92 parallel to the cylindrical axis of the large end hole 53 facing the large end hole 53 on the projection 56, the engagement end surface 91 is formed when the engagement portion 60 and the circular hole 54 are fitted. And the fixing end face 92 are joined, the locking hole 59 and the fixing hole 55 can be accurately matched, and the assembling can be performed easily. Further, the locking portion 6 between the small end portion 50 and the large end portion 52
The fixation around the axis of 0 and the left and right direction can be strengthened,
The behavior of the connecting rod 19 can be stabilized.

In this embodiment, the locking projection 61 and the fixing groove 63 are provided, but the same effect can be obtained without this.

[0091]

As described above, the present invention has a small end connected to a piston by a small end hole by a piston pin, and a large end connected to an eccentric shaft of a crankshaft by a large end hole. A reciprocating piston compressor including a connecting rod, wherein a large end of the connecting rod has a cylindrical hole and a projection having a fixing hole communicating therewith, and the hole has a hemispherical or substantially circular bottom shape. It is a weight, and is provided at a depth that does not penetrate the large end hole from the end surface of the projection to the center of the large end hole, and the small end has a cylindrical rod portion that is long in the radial direction. Constitutes a locking hole at the end and a locking portion with a hemispherical or substantially conical shape at the end. The locking portion is loosely fitted or lightly press-fitted into the circular hole of the projection, and the fixing hole and By connecting the locking hole and inserting the locking pin, the locking part and the circular hole are locked,
By maintaining the geometric axes of the small end hole at the small end of the connecting rod and the large end hole at the large end on the same plane, machining and assembly with high precision can be easily performed, and It is possible to prevent twisting of the large end hole and twisting with the fitted object, thereby preventing a reduction in efficiency due to an increase in rotational load and an increase in noise and vibration.

Further, by providing the cylindrical locking portion of the rod portion and the cylindrical portion of the projection with a flat portion, positioning when the locking portion is fitted into the hole can be performed. The assembling of the connecting rod can be performed with high accuracy, and the rotation of the locking portion around the axis is fixed, so that a reduction in efficiency due to an increase in the rotational load and an increase in noise and vibration can be prevented.

Also, an oil hole is provided for communicating the top of the circular hole with the large end hole, and the oil hole is communicated with the oil groove of the eccentric shaft of the crankshaft, so that the engaging portion and the circular hole are positively connected. Lubrication can be performed, abrasion due to metal contact can be prevented, and reliability can be improved.

Further, a locking groove is provided in the cylindrical locking portion of the rod portion, and a fixing groove is provided in the flat portion of the projection, and the locking portion of the rod portion is loosely fitted or lightly pressed into the circular hole of the projection. At the same time, the locking portion and the circular hole portion are locked by fitting the fixing plate by communicating with the locking groove from the fixing groove, and the small end hole at the small end portion and the large end hole at the large end portion of the connecting rod. By maintaining the geometric axis arrangement on the same plane, the connection between the locking portion and the circular hole portion can be firmly performed by the fixing plate, and the behavior of the connecting rod can be stabilized. As a result, it is possible to reduce a decrease in efficiency and an increase in noise and vibration due to an increase in the rotational load of the compressor due to loose connection and the like.

Further, by providing between the rod portion and the locking portion, a holding portion having an auxiliary flat portion that is joined to the end surface portion of the projection portion at the time of fitting with the circular hole portion, so that the locking portion and the circular portion are provided. The holes can be efficiently connected, and the load acting on the auxiliary plane portion and the end surface portion during compression can be dispersed, so that the behavior of the connecting rod can be stabilized. As a result, it is possible to prevent a decrease in efficiency and an increase in noise and vibration due to an increase in the rotational load of the compressor.

Also, a second locking projection having a locking end surface parallel to the cylindrical axis of the small end hole is provided between the rod portion and the locking portion, and the large end projection is provided on the large end projection. By providing a fixed end face parallel to the cylindrical axis direction of, the locking end face and the fixed end face are joined at the time of connecting the small end and the large end, and the fitting position of the small end and the large end is defined, thereby achieving accuracy. The engaging portion and the circular hole can be connected well, and assemblability is improved, and the connecting portion of the connecting rod is prevented from being displaced around the axis and in the left-right direction, and the behavior of the connecting rod is stabilized. As a result, it is possible to prevent a decrease in efficiency and an increase in noise and vibration due to an increase in rotational load.

[Brief description of the drawings]

FIG. 1 is a longitudinal sectional view of a first embodiment of a reciprocating piston compressor according to the present invention.

FIG. 2 is an exploded view of a connecting rod and a piston before assembling a reciprocating piston compressor of the reciprocating piston of the reciprocating piston compressor of the embodiment.

FIG. 3 is a plan view of the reciprocating piston compressor of the embodiment before a connecting rod is assembled.

FIG. 4 is a partial longitudinal sectional view of the reciprocating piston compressor according to the embodiment when the connecting rod is assembled.

FIG. 5 is a plan view of a reciprocating piston compressor according to a second embodiment of the present invention before a connecting rod is assembled.

FIG. 6 is a view of a large end portion A before assembling of a connecting rod according to a second embodiment of the reciprocating piston compressor of the present invention.

FIG. 7 is a partial longitudinal sectional view of a reciprocating piston compressor according to a second embodiment of the present invention when a connecting rod is assembled.

FIG. 8 is a partial longitudinal sectional view of a connecting rod and an eccentric shaft during a suction stroke of a reciprocating piston compressor according to a third embodiment of the present invention.

FIG. 9 is a partial longitudinal sectional view of a connecting rod and an eccentric shaft during a compression stroke of a reciprocating piston compressor according to a third embodiment of the present invention.

FIG. 10 is a plan view of a reciprocating piston compressor according to a fourth embodiment of the present invention before assembling a connecting rod.

FIG. 11 is a partial longitudinal sectional view of a reciprocating piston compressor according to a fourth embodiment of the present invention when assembling a connecting rod.

FIG. 12 is a plan view of a reciprocating piston compressor according to a fifth embodiment of the present invention before a connecting rod is assembled.

FIG. 13 is a partial longitudinal sectional view of a reciprocating piston compressor according to a fifth embodiment of the present invention when a connecting rod is assembled.

FIG. 14 is a plan view of a reciprocating piston compressor according to a sixth embodiment of the present invention before a connecting rod is assembled.

FIG. 15 is a partial longitudinal sectional view of the reciprocating piston compressor according to the present invention when assembling the connecting rod of the sixth embodiment.

FIG. 16 is a longitudinal sectional view of a conventional reciprocating piston compressor.

FIG. 17 is an exploded view of a connecting rod and a piston before assembling a conventional reciprocating piston compressor.

FIG. 18 is an exploded plan view of a large end and a small end of a connecting rod of a conventional reciprocating piston compressor.

[Explanation of symbols]

 Reference Signs List 3 housing 7 crankshaft 10 piston 11 eccentric shaft 15 piston pin 19 connecting rod 50 small end 51 small end hole 52 large end 53 large end hole 54 circular hole 55 fixing hole 56 projection 57 end face 58 rod 59 Stop hole 60 Locking portion 61 Locking projection 63 Locking groove 65 Locking pin 70 Fixing flat portion 71 Locking flat portion 75 First oil supply hole 76 Second oil supply hole 77 Side oil hole 78 Oil groove 79 Communication oil hole 80 Lock Groove 81 Fixing groove 82 Fixing plate 83 Key part 85 Holding part 86 Auxiliary flat part 90 Second locking protrusion 91 Locking end face 92 Fixed end face

Claims (6)

[Claims] 1. A reciprocating piston compressor comprising a connecting rod having a small end connected to a piston by a small end hole by a piston pin and a large end connected to an eccentric shaft of a crankshaft by a large end hole. The large end of the connecting rod has a cylindrical hole and a protrusion having a fixing hole communicating therewith, and the hole has a hemispherical or substantially conical bottom shape, and an end surface of the protrusion. From the center of the large end hole to a depth that does not penetrate the large end hole, the small end portion has a cylindrical rod portion that is long in the radial direction, and the rod portion has a locking hole and a tip Constitutes a hemispherical or substantially conical locking portion. The locking portion is loosely fitted or lightly press-fitted into the circular hole portion of the projection, and the locking pin communicates with the fixing hole to form a locking pin. By inserting the rod, the locking portion and the circular hole are locked, and the number of the small end hole at the small end and the large end hole at the large end of the connecting rod is adjusted. A reciprocating piston compressor characterized by maintaining the arrangement of geometric axes on the same plane. 2. The reciprocating piston compressor according to claim 1, wherein a flat portion is provided in the cylindrical locking portion of the rod portion and the cylindrical hole portion of the projection. 3. The reciprocating piston according to claim 1, wherein an oil hole is provided for communicating between the top of the circular hole and the large end hole, and the oil hole communicates with the oil groove of the eccentric shaft of the crankshaft. Compressor. 4. A locking groove in a cylindrical locking portion of a rod portion,
A fixing groove is provided on the flat surface of the projection, and the locking portion of the rod portion is loosely fitted or lightly press-fitted into the circular hole of the projection, and the fixed plate is fitted by communicating from the fixing groove to the locking groove. The locking portion and the circular hole portion are locked to maintain the geometric axes of the small end hole at the small end of the connecting rod and the large end hole at the large end on the same plane. Item 2. A reciprocating piston compressor according to Item 1. 5. A holding portion having an auxiliary flat portion that joins with an end surface portion of a projection when fitted to a circular hole portion is provided between the rod portion and the locking portion. A reciprocating piston compressor as described. 6. A second locking projection having a locking end surface parallel to the cylindrical axis of the small end hole is provided between the rod portion and the locking portion, and a large end hole is provided in the large end projection. The fixed end face parallel to the cylindrical axis direction is provided, and when the small end and the large end are connected, the locking end face and the fixed end face are joined to define the fitting position of the small end and the large end. The reciprocating piston compressor according to claim 1, wherein