JPH0275777A - Piston device assembly method for compressor - Google Patents

Abstract

PURPOSE:To simplify an assembly work by a method wherein a piston can be coupled to a crank pin through a simple work in which a spring member intended to be inserted in the pore of a connecting rod is inserted in the pore of the connecting rod as the spring member is engaged with a cylinder body engaged with a crank pin. CONSTITUTION:During assembly of a piston device, a crank shaft 5 is first inserted in a bearing part 8 of a motor case 6. Meanwhile, a piston 15 pivotally supported to a connecting rod 14 is inserted in a cylinder 9. In this case, a spring member 16 is mounted in a pore 19 of the connecting rod 14. After the end part of the connecting rod 14 is pressed in a hole 17 of a cylinder body 12 engaged with a crank pin 13, the spring member 16 is engaged with an engaging groove 18 of the cylinder body 12 to intercouple the connecting rod 14 and the cylinder body 12. This completes assembly of a piston device. In this case, the stroke of the piston is decided by means of the depth of a hole 17 of the cylinder body 12, and a top size is regulated through tuning of the insertion depth of the connecting rod 14.

Description

DETAILED DESCRIPTION OF THE INVENTION (a) Field of Industrial Application The present invention relates to a method for assembling a piston device of a compressor used in refrigerators, freezer showcases, and the like.

(B) Prior Art Conventionally, a piston device for this type of compressor, that is, a compressor equipped with a motor case in which a cylinder is integrally formed, has been disclosed, for example, in Japanese Patent Publication No. 51-21165. The inner diameter of the cylindrical body to be inserted into the crank pin is made larger than the outer diameter of the pin, and while the crank pin is set in a predetermined position in the motor case, with the piston inserted into the cylinder, The cylindrical body was loosely fitted onto the crank pin by tilting a connecting rod supported by the cylinder, and then a cylindrical spacer was filled between the cylindrical body and the crank pin.

(c) Problems to be Solved by the Invention However, according to the above configuration, a cylindrical spacer is required when connecting the cylindrical body and the rank pin. The crank pin had to be made smaller in diameter, which led to problems such as an increase in the size of the compressor and deformation due to reduced strength of the crank pin, causing play.

In addition, as a structure that does not cause such problems, for example,
As disclosed in Japanese Utility Model Publication No. 56-20548, there is a structure in which a cylindrical body is divided into two parts, but in this case, there is a problem that the assembly work is complicated because it requires bolts, etc. .

The present invention has been made in view of the above points, and provides a method for assembling a piston device of a compressor with good performance and good assembly workability without increasing the size of the compressor or reducing the strength of the crank pin. The purpose is to provide

(d) Means for Solving the Problems The present invention is characterized in that a compressor section and an electric motor section for driving the compressor section are housed in a sealed case, and both these sections are connected by a crankshaft, and the electric motor section A cylinder constituting the compressor section is integrally formed with a motor case fixed to the motor case, and a piston that reciprocates within this cylinder and a crank pin of a crankshaft are connected to a cylindrical body fitted into the pin and this cylindrical body. In the case where the cylindrical body and the connecting rod are separated, a hole is formed on one side of the cylindrical body and an engagement groove is formed on the other side, and an engaging groove is formed on the other side of the cylindrical body, and an engaging groove is formed on the other side of the cylindrical body. After inserting the piston with the connecting rod into the cylinder, inserting the piston into the cylinder, inserting the cylinder into the crank pin, and inserting the end of the connecting rod into the hole in the cylinder,
The connecting rod and the cylindrical body are connected by a spring member whose abdomen is engaged with the engagement groove of the cylindrical body and whose tip end is inserted into the pore of the connecting rod.

(E) Function The method for assembling a piston device for a compressor of the present invention connects the piston and crank pin by a simple operation of engaging the spring member with the engagement groove of the cylindrical body and inserting it into the pore of the connecting rod. This not only simplifies the assembly work, but also
It is possible to make the cylindrical body as small as possible and to make the crank pin as large in diameter as possible, making it possible to downsize the compressor and reduce backlash. Moreover, according to this method, by appropriately changing the position of the connecting rod's pore and the depth of insertion into the hole of the cylindrical body, the stroke can be easily changed, and it is possible to correspond to compressors of different capacities.

(f) Example Embodiments of the present invention will be described below with reference to the drawings.

Reference numeral 1 designates a hermetic compressor in which a compressor section 3 and an electric motor section 4 for driving the compressor section 3 are housed in a closed case 2, and these both sections 3.4 are connected by a crankshaft 5. Reference numeral 6 denotes a motor case fixed to the electric motor section 4. This motor case has a mounting leg 7 to the electric motor section 4 and a crankshaft 5.
The bearing portion 8 and cylinder 9 are integrally formed. 10 is a piston device constituting the compressor section 3, which has a sphere 1 at one end.
A connecting rod 1 has a cylindrical body 12 fixed to the other end by a spring member 16 and is fitted into a crank pin 13 of a crankshaft 5.
4, and a piston 15 that is connected to the sphere 11 by a ball joint system and reciprocates within the cylinder. Here, a hole 17 is provided on one side of the cylindrical body 12, an engagement groove 18 is provided on the other side, and a small hole 19 is provided on the end of the connecting rod 14. 20 is the crankshaft 5
It is a balancer formed in the shape of a shaft and has a thrust bearing surface on the lower surface.

Next, a method for assembling the piston device will be explained.

First, as shown in FIG.
Insert the crankshaft 5 into the On the other hand, the piston 15 with the connecting rod 14 pivotally supported is inserted into the cylinder 9. At this time, the spring member 16 is attached to the small hole 19 of the connecting rod 14.

After the end of the connecting rod 14 is press-fitted into the hole 17 of the cylindrical body 12 as shown in FIG.
The connecting rod 14 and the cylindrical body 12 are connected by fitting into the engaging groove 18 of the connecting rod 14 and the cylindrical body 12. The piston device is thus assembled. Here, the stroke of the piston is determined by the depth of the hole 17 in the cylindrical body 12, and the top dimension is adjusted by finely adjusting the insertion depth of the connecting rod 14. Incidentally, when a large capacity change is required, it is convenient to provide a plurality of pores in the connecting rod 14 in advance.

A method for assembling such a piston device is to assemble the spring member 16.
While inserting the tip of the connecting rod into the small hole 19 of the connecting rod 14 (in this embodiment, it is inserted in advance), the abdomen is inserted into the engagement groove 1 of the cylindrical body 12.
The piston 15 and crank pin 13 can be connected by the simple operation of engaging the piston 15 with the cylinder 9, which not only simplifies the assembly work but also requires conventional spacers etc. even if the motor case 6 is integrally formed with the cylinder 9. Therefore, the cylindrical body 12 is made as small as possible and the crank pin 13 is made as small as possible.
This allows the compressor to be made as large in diameter as possible, making it possible to reduce the size and weight of the compressor and reduce backlash. Also,
According to this method, the stroke of the piston 15 can be changed simply by appropriately changing the position of the fine hole 19 of the connecting rod 14 and the insertion depth into the hole 17 of the cylindrical body 12, so that it can be easily applied to compressors of different capacities. I can handle it.

(G) Effects of the Invention As described above, according to the compressor piston device assembly method of the present invention, even a motor case having an integral cylinder can be assembled without using a spacer as in the conventional case. In addition to simplifying assembly work,
By forming the crank pin with a large diameter and a small cylindrical body, a compressor with good performance can be provided by preventing rattling due to reduced strength of the crank pin and increasing the size of the piston device. In addition, compressors with different capacities can be easily handled.

[Brief explanation of the drawing]

FIG. 1 is a vertical cross-sectional view of a hermetic compressor showing an embodiment of the present invention, FIG. 2 is a vertical cross-sectional view of a piston device, FIG. 3 is a cross-sectional view of the main part of the piston device, FIG. 5 is an exploded sectional view showing a method of assembling the piston device. 5... Crankshaft, 6... Motor case, 9...
・Cylinder, 12... Cylindrical body, 13... Crank pin, 14... Connecting rod, 15... Piston, 16...
・Spring member, 17... Hole, 18... Engagement groove, 19.
··pore. 11 (Figure 2 Figure 3

Claims (1)

[Claims] 1. A compressor unit and an electric motor unit that drives the compressor unit are housed in a sealed case, and these two units are connected by a crankshaft, and the compressor unit is configured in a motor case fixed to the electric motor unit. A piston that reciprocates within this cylinder and a crank pin of a crankshaft are connected by a cylindrical body fitted into the pin and a connecting rod connected to this cylindrical body. In,
The cylindrical body and the connecting rod are separated, a hole is provided on one side of the cylindrical body, an engagement groove is provided on the other side, and a small hole is provided at the end of the connecting rod, and the piston with the connecting rod attached thereto is provided. After inserting the connecting rod into the cylinder and fitting the cylindrical body into the crank pin, and further inserting the end of the connecting rod into the hole of the cylindrical body, the abdomen is engaged with the engagement groove of the cylindrical body, and the tip of the connecting rod is inserted into the cylinder. A method for assembling a piston device for a compressor, characterized in that a connecting rod and a cylindrical body are connected by a spring member whose portion is inserted into a pore of the connecting rod.