Piston compressor, particularly hermetically enclosed refrigerant compressor
The invention relates to a piston compressor, particularly a hermetically enclosed refrigerant compressor, with a crank drive, having a crank shaft with an eccentric crank pin and an oil channel arrangement, and a connecting rod with a first piston-side connecting rod eye and a second pin-side connecting rod eye, said eyes having between them a connecting rod shank with a longitudinal channel, which opens into the connecting rod eyes. In this compressor, it is endeavoured to improve the lubricating conditions. For this purpose a bearing element is arranged between the crank pin and the second connecting rod eye, which is unrotatably connected with the second connecting rod eye under formation of an oil channel, the longitudinal channel communicating with the oil channel and a control arrangement being provided, which ensures a communication between the oil channel and the oil channel arrangement at least once per rotation of the crank pin.
1. A hermetically enclosed refrigerant compressor comprising:
a compressor block having a bore extending therethrough;
a crank shaft positioned for rotation in the bore, the crank shaft defining an eccentric crank pin at one end thereof;
the crank shaft and crank pin cooperating to define an oil channel arrangement;
a connecting rod attached at one end to a bearing element such that there is no relative motion between the bearing element and the connecting rod, the connecting rod having a passage extending therethrough and in communication with a channel formed by the cooperation of the connecting rod and the bearing element, the bearing element being formed as a single piece having a substantially cylindrical shape and the channel extending completely around a circumference of the bearing element;
the crank pin extending into the bearing element and being positioned for rotation relative thereto; and
a control arrangement providing communication between the channel and the oil channel arrangement, at least once per revolution of the crank pin.
2. A compressor according to claim 1 , wherein the control arrangement comprises at least one radial bore in the bearing element, which bore overlaps an oil source upon a rotation of the crank pin.
3. A compressor according to claim 2 , wherein the oil source is formed by an opening in the crank pin and forming part of the oil channel arrangement.
4. A compressor according to claim 3 , wherein the crank pin defines an oil pocket in a area proximate the opening forming part of the oil channel arrangement.
5. A compressor according to claim 2 , wherein the passage defines an opening into the channel and the radial bore is offset in a circumferential direction relative to the opening.
6. A compressor according to claim 1 , wherein the connecting rod includes a first connecting rod eye opposite the end attached to the bearing element, the connecting rod eye surrounding a piston bolt having a lubrication channel that overlaps the passage at least once during a revolution of the crank pin, the control arrangement establishing the communication between the passage and the channel.
7. A compressor according to claim 1 , wherein the control arrangement establishes the communication during a suction phase of the compressor.
8. A compressor according to claim 1 , wherein the control arrangement further establishes the communication when a compression phase of the compressor begins.
9. A compressor according to claim 8 , wherein the bearing element defines two radial bores arranged at a predetermined distance relative to each other and to the opening of the passage.
10. A compressor according to claim 1 , wherein the connecting rod defines a rod eye positioned over the bearing element, wherein at least one of the bearing element and the rod eye includes an alignment mark for aligning said bearing element with said rod eye.