JPH01198253A - Manufacture of electric compressor - Google Patents

Abstract

PURPOSE:To improve plane accuracy, and to equalize an air gap by abutting a frame body against a stator core constituted by impregnating a gaps between silicon steel plates having a central hole for a shaft and an inserting hole for a bolt with varnish and fastening the plates and a frame body with the bolt. CONSTITUTION:A motor section 3 and a compressor section 4 are housed into a closed case 2, thus constituting an electric compressor. The motor section 3 is composed of a stator core 5, in which a plurality of silicon steel plates 5a are laminated, a hole 6 is formed at the center and a hole 7 for a bolt is shaped to an edge section, and a rotor 9 fitted to a shaft 8. The compressor 4 is attached to a frame body 12 having a bearing section 10 and mounting leg sections 11. Gaps between the silicon steel plates 5a are impregnated with varnish, the stator core 5 is pushed by a jig not shown, varnish is wiped off, and baking treatment is executed and a coil 15 is wound. The bolt 14 is inserted into the hole 7, and screwed into a tapped hole 13 for the mounting leg section 11. Accordingly, the flatness of the stator core 5 and the frame bodies 11 is improved, and air gaps are equalized, thus acquiring a device noises from which are reduced.

Description

DETAILED DESCRIPTION OF THE INVENTION (a) Field of Industrial Application The present invention relates to a method of manufacturing an electric compressor used in refrigerators, air conditioners, etc.

(B) Conventional technology As disclosed in Japanese Patent Publication No. 62-30311, etc., this type of electric compressor has traditionally been made of laminated silicon steel plates with a hole in the center for housing the rotor and a hole in the edge. A stator core having bolt insertion holes formed in four places and a frame body to which the compressor section is attached are tightened and fixed by bolts inserted into the bolt insertion holes and screwed into threaded holes in the mounting legs of the frame body. It was composed of

However, according to the above configuration, each of the silicon steel plates has a thickness of 0.
Since it is formed by press punching of a flank material that is a thin plate of about 51'1IT1, each silicon steel plate itself has a slight distortion, and this distortion creates a gap between each silicon steel plate. For this reason, not only is the tightening force of the bolts used to eliminate the gap, but also the plane accuracy of the end face of the stator core deteriorates, and when the stator core and the frame are fixed, the There is a problem in that the air gap tends to become non-uniform, resulting in failure to start the motor. In addition, the stator core is prone to slight vibrations due to the gaps between the silicon steel plates mentioned above, and the compressor! There was a problem that the A sound was promoted.

(c) Problems to be Solved by the Invention Therefore, conventionally, as disclosed in Japanese Patent Publication No. 62-45779, the outer periphery of the bolt insertion hole of the stator core is partially pressurized in the stacking direction to tighten the bolt. There are those that prevent the force from decreasing, and those that solidify the stator core by penetrating the gaps between the silicon steel plates with varnish, as disclosed in Japanese Patent Publication No. 47-48323. The flatness accuracy of the end face of the stator core could not be improved as much as desired, and motor starting failures still occurred due to non-uniformity of the air gap.

The present invention has been developed in view of these points, and it not only improves the tightening torque of bolts, but also improves the flatness accuracy of the end face of the stator core (in particular, the contact surface of the frame), thereby reducing the air gap size. It is an object of the present invention to provide a method for manufacturing an electric compressor that achieves uniformity, prevents minute vibrations of the core, has good starting characteristics, and has low noise.

(d) Means for Solving the Problems The present invention provides a stator core in which silicon steel plates are laminated and a rotor housing hole is formed in the center and bolt insertion holes are formed in the edge.
The stator core includes a frame fixed to the core by bolts that are inserted into the bolt insertion holes from one end surface side and screwed into screw holes in the mounting legs, and a compressor section that is attached to the frame. The stator core is formed by impregnating the gaps between the steel plates with a fixing agent such as varnish, and then applying pressure in the stacking direction to the end surface that the mounting legs of the frame come into contact with.

(E) Function The method for manufacturing an electric compressor of the present invention prevents minute vibrations of the stator core by impregnating the gap between each silicon steel plate of the stator core with a fixing agent such as varnish to harden the core. In addition, by filling the space between each silicon steel plate with a bonding agent and applying pressure in the stacking direction to the end face of the core that the mounting leg of the frame comes into contact with, the pressing force is applied by the elastic action of the bonding agent. The pressure can be applied to the entire pressure surface of the silicon steel plate, improving the flatness accuracy of the end face of the stator core where the frame comes into contact, and making the air gap dimension uniform when the core and frame are fixed, making it possible to start the electric motor. This can reduce defects. Further, since the stator core is firmly solidified by both the binding agent and the pressing force in the direction of stack W1 after treatment with the binding agent, there is no reduction in bolt tightening torque.

(f) Example Embodiments of the present invention will be described below based on the drawings.

Reference numeral 1 denotes an electric compressor which houses a motor part 3 and a compressor part 4 driven by the motor part in a sealed case 2. The electric motor section 3 includes a stator core 5 which is made by laminating a plurality of silicon steel plates 5a and has a hole 6 in the center and bolt insertion holes 7 at the edges, and a stator core 5 that can be accommodated in the hole 6 of this core and fitted onto a rotating shaft 8. It consists of a rotor 9. The compressor section 4 includes a piston and a cylinder (not shown), and is mounted on a frame 12 having a bearing section 10 and a mounting leg section 11. The frame body 12 and the stator core 5 are connected by bolts 14 inserted into the bolt insertion holes 7 from the lower end side of the cores and screwed into the screw holes 13 of the mounting legs 11. Here, the stator core 5 is made by laminating a plurality of silicon steel plates 5a and clamping them into a predetermined shape by caulking, welding, etc., and then immersing them in a varnish bath (not shown). As a result, the gaps between the silicon steel plates 5a of the stator core 5 can be impregnated with varnish, and then the varnish is removed, wiped off, and baked (heated in a drying oven at 145 to 155°C for 5 to 6 hours. The varnish is cured and the stator core is solidified. After coils 15 such as main windings and auxiliary windings are wound around the varnished stator core 5, the coils are also solidified into a predetermined shape by dropwise impregnation with varnish. Stator core 5 formed in this way
is then subjected to pressing as shown in FIG.

That is, the lower guide block 1 having three presser parts 16
7 and a donut-shaped presser portion 18.
9, the stator core 5 is pressurized in the stacking direction with a force of about 25 t×1 second. Here, on the upper end surface A of the stator core 5 (the lower surface when pressurizing), the contact surface 5b with the mounting leg part 16 including the outer periphery of the two adjacent bolt insertion holes 7, and both contact surfaces are opposed. Pressing is carried out so that the surface 5d of the lower end surface B (the upper surface when pressing) of the core is pressurized so that the surface 5c located in the position is pressurized intensively. Process. Then, the stator core 5 and the frame body 12 are connected to the bolts 1 so that the contact surface 5b and the bottom surface of the mounting leg portion 11 are in contact with each other.
4, it is firmly fixed.

In the method for manufacturing a compressor, the stator core 5 is clamped and then the gaps between the silicon steel plates 5a are impregnated with varnish and hardened, so that slight vibrations of the core can be prevented. In addition, since the stator core 5 is partially pressurized after filling the gap between each silicon steel plate 5a with 7 varnish, the pressurized surfaces 5c and 5d including the contact surface 5b are pressurized by the elastic action of the varnish. The pressure can be spread over the entire pressurizing surface, the bias of the pressurizing force within the pressurizing surface can be corrected, the planar accuracy of the contact surface 5b can be significantly improved, and the air gap size of the electric motor section 3 can be reduced. It can be made uniform.

Furthermore, since the stator core 5 is solidified by both the varnish and the partial pressure applied after the varnish, as described above,
Bolt tightening torque does not decrease due to gaps between silicon steel plates.

(G) Effects of the Invention As described above, according to the present invention, it is possible to significantly improve the planar accuracy of the contact surface of the stator core with the frame, and to make the air gap dimension uniform. It is possible to provide an electric compressor that can reduce minute vibrations, has good starting characteristics, and has low noise.

[Brief explanation of the drawing]

FIG. 1 is a longitudinal sectional view of an electric compressor showing an embodiment of the present invention;
Figure 2 is an exploded sectional view of the stator core and frame, Figures 3 and 4 are sectional views and perspective views showing the stator core press working method, Figure 5 is a sectional view of the main parts of the stator core, and Figure 6 is the press The top view of the stator core during processing, and FIG. 7 are also bottom views. 5... Stator core, 5a... Silicon steel plate,
5b... Contact surface, 6... Hole, 7... Bolt insertion hole, 11... Mounting leg, 12... Frame, 14... Bolt.

Claims (1)

[Claims] (1) A stator core made of laminated silicon steel plates with a hole for storing the rotor in the center and bolt holes in the edges, and a screw in the mounting leg that is inserted into the bolt hole from one end of the stator core. The stator core includes a frame fixed to the core by bolts screwed into holes, and a compressor section attached to this frame, and the stator core is made by impregnating gaps between steel plates with a fixing agent such as varnish. . A method of manufacturing an electric compressor, characterized in that the frame is formed by applying pressure in the stacking direction to an end surface in contact with the mounting legs of the frame.