Method of manufacturing a crank shaft for a hermetic reciprocal compressor
First Claim
1. A crank shaft for a hermetic reciprocal compressor, wherein the crank shaft includes a main shaft connected with a rotor of the hermetic reciprocal compressor;
- and a crank portion eccentric to a predetermined degree with respect to the main shaft connected with a connecting rod, and the main shaft and the crank portion being joined to each other through laser welding, after the main shaft is formed as a hollow pipe, and the crank portion is formed by sinter molding.
1 Assignment
0 Petitions
Accused Products
Abstract
A method of manufacturing a crank shaft for a hermetic reciprocal compressor including the steps of providing a main shaft and a crank portion eccentric for a predetermined degree from the main shaft that are separately formed. The main shaft and the crank portion are joined through laser welding. The main shaft is a hollow pipe and the crank portion is made by sintering. The main shaft and the crank portion are connected, and an end portion of the main shaft is inserted into an annular groove formed at a main shaft connection side of the crank portion. Accordingly, the main shaft is a drawn steel pipe, and the crank portion is formed by sintering, thus the crank shaft becomes lighter and no post-process is needed. Therefore, the manufacturing process is remarkably reduced, and the crank shaft manufactured at a lower production cost.
-
Citations
11 Claims
-
1. A crank shaft for a hermetic reciprocal compressor,
wherein the crank shaft includes a main shaft connected with a rotor of the hermetic reciprocal compressor; - and
a crank portion eccentric to a predetermined degree with respect to the main shaft connected with a connecting rod, and the main shaft and the crank portion being joined to each other through laser welding, after the main shaft is formed as a hollow pipe, and the crank portion is formed by sinter molding. - View Dependent Claims (2, 3, 4, 5)
- and
-
6. A method for manufacturing a crank shaft for a hermetic reciprocal compressor, comprising the steps of:
-
providing a crank shaft including a main shaft for connection with a rotor of the hermetic reciprocal compressor; and
connecting a connecting rod to a crank portion of the crank shaft so as to be eccentric to a predetermined degree with respect to the main shaft, forming the main shaft as a hollow pipe;
and forming the crank portion by sinter molding; and
laser welding the main shaft and the crank portion. - View Dependent Claims (7, 8, 9, 10)
-
-
11. A method of manufacturing a crank shaft for a hermetic reciprocal compressor having a main shaft and a crank portion eccentric to a predetermined degree from the main shaft, comprising the steps of:
-
preparing the main shaft by drawing and cutting a carbon steel hollow pipe of a predetermined length, and forming at least one oil passage in the hollow carbon steel pipe;
preparing the crank portion by forming a molded product having an eccentric shaft and a weight balancer by sintering a metallic alloy powder, forming at least one oil passage in the molded product, and forming an annular groove in one side of the molded product at a predetermined depth;
connecting the main shaft and the crank portion by inserting an end portion of the main shaft into the annular groove of the crank portion;
joining the main shaft and the crank portion by laser welding the main shaft to the crank portion where the two intersect;
forming an oxide coating for increasing corrosion and abrasion resistance of the joined crank shaft; and
final clean cutting.
-
Specification