JPH04237891A - Motor driven compressor - Google Patents

Abstract

PURPOSE:To form a balance weight with one type balance weight plate and to adjust the balance in an easy manner by making up the balance weight plate with a balance adjusting part. CONSTITUTION:Plural pieces of balance adjusting parts 53 made cuttable as surrounded by intermitting slits 52 are formed in a balance weight plate 51 consisting of a circular sheet. Each balance adjusting part 53 is cut off for weight adjustment, so that weight adjustment takes place only cutting the balance adjusting parts 53. Accordingly, when a balance value ascribable to a balance weight 5 is varied to some extent, this weight adjustment is easily performable. In this connection, the balance weight plate 51 is formable all with the same die, and fine adjustment for this balance weight 5 is also simple.

Description

[Detailed description of the invention]

0001

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an electric compressor having a motor and a compression element housed in a sealed casing, and a balance weight provided at the end of the rotor of the motor.

0002

[Prior Art] Conventionally, as a balance weight provided in this type of electric compressor, for example, Japanese Patent Application Laid-Open No. 63-28250
As described in the above publication and shown in FIG. 5, a balance weight C, which is made by laminating a plurality of balance weight plates C1 made of arc-shaped thin plates, is attached to an end ring B provided at the end of the rotor A of the motor. The rotational balance of the rotor A and the rotational balance of the drive shaft are maintained appropriately.

0003

[Problems to be Solved by the Invention] However, in the electric compressor, the shape and mass of the eccentric rotating portion of the compression element are determined according to the set compression capacity of the compressor, and then the drive shaft A predetermined number of the balance weights C are attached in order to cancel out the centrifugal force generated in the eccentric rotating portion and the couple generated in the drive shaft due to this centrifugal force during rotation of the drive shaft. Therefore, when adjusting the amount of the balance weight C according to the centrifugal force, the adjustment amount can only be adjusted by the weight of each balance weight plate C1, so the adjustment is made for each balance weight plate C1. Therefore, it was not possible to adjust the balance to the optimum amount. In addition, in order to adjust the amount to the optimum amount, it is possible to prepare multiple types of the balance weight plates C1 with different plate thicknesses, or prepare multiple types of balance weights with different shapes, and change the combination thereof. It is conceivable that the number of types of the balance weight plates C1 increases, which causes problems such as higher manufacturing costs and more complicated parts management.

The present invention has been made in view of the above problems, and an object of the present invention is to form a balance weight plate having a balance adjustment part, and to stack one type of balance weight plates to obtain a desired balance weight. An object of the present invention is to provide an electric compressor that can easily adjust its mass to an optimum amount while forming a compressor. Another purpose is to provide an electric compressor that can reduce the shift of the center of gravity of the balance weight even if an adjustment section is provided on the balance weight plate; another purpose is to finely adjust the balance in stages. Our goal is to provide an electric compressor that can.

[0005]

[Means for Solving the Problems] In order to achieve the above object, the present invention includes a motor 2 and a compression element 3 inside a sealed casing 1, and a balance weight 5 at the end of the rotor 22 of the motor 2. In an electric compressor equipped with
The balance weight 5 is formed by laminating a plurality of balance weight plates 51 made of arc-shaped thin plates, and
The balance weight plate 51 is surrounded by intermittent slits 52 and has a plurality of balance adjustment parts 53 that can be cut out.
was formed.

[0006] Furthermore, the balance adjustment portions 53 of the balance weight plate 51 are disposed in the arcuate length direction of the balance weight plate 51, and the balance adjustment portions 53 are arranged at the intermediate portion in the longitudinal direction and at the intermediate portion. However, it is preferable to provide them at symmetrical positions.

Further, the balance weight plate 51 is provided with three balance adjustment parts 53 having different cutout areas, and the weight when all the sizes of these adjustment parts 53 are cut out is 50% of the total weight of the balance weight plate 51. It is preferable that the size of each of the balance adjustment parts 53 is such that the weight reduction when cut out is in five stages of 10 to 50%.

[0008]

[Function] Balance weight plate 51 made of arc-shaped thin plate
When forming the balance weight 5 by laminating a plurality of sheets, a plurality of balance adjustment parts 53 surrounded by intermittent slits 52 and made cuttable were formed on the balance weight plate 51. By adjusting the mass with 53, the movement by the balance weight 5 can be adjusted, such as when the diameter of the eccentric shaft portion of the drive shaft changes and the capacity of the cylinder chamber of the compressor changes, or when the length of the drive shaft changes. When the target and static balance change, the mass of the balance weight 5 can be adjusted only by the balance adjustment section 53 without having to provide many types of the balance weight plates 51. 51
While all can be formed using the same mold, the mass can be adjusted by simply cutting out the adjustment portion 53, and the balance weight 5 can also be adjusted easily.

[0009] Further, the balance adjusting portions 53 of the balance weight plate 51 are arranged in the arcuate length direction of the balance weight plate 51, and the balance adjusting portions 53 are arranged at the intermediate portion in the longitudinal direction and at the intermediate portion. On the other hand, by providing the balance weights 5 at symmetrical positions, even if the balance adjustment section 53 is removed, the shift in the center of gravity of the balance weight 5 can be reduced.

Furthermore, the balance adjustment section 53 has a size such that the weight when all the balance adjustment sections 53 are cut out is 50% of the total weight of the balance weight plate 51, and each of the balance adjustment sections 53. By forming the size of the balance weight plate 51 in five steps from 10 to 50% in weight reduction when cut, the number of balance weight plates 51 to be used and the balance adjustment portion 53 cut out can be adjusted. By combining them, you can fine-tune the balance in stages.

[0011]

[Example] The hermetic compressor shown in Fig. 4 has an oil reservoir 1a at the bottom.
A motor 2 is installed in the upper part of a sealed casing 1 having a
A compression element 3 consisting of a cylinder 31 and a front head 32 and a rear head 33 arranged above and below the cylinder 31 is disposed below the motor 2, and this compression element 3 extends from the rotor 22. It is designed to be rotated by a drive shaft 4.

The motor 2 includes a stator 21 that is integrally fixed to the inner wall of the casing 1, and a stator 21 that is integrally fixed to the inner wall of the casing 1.
The rotor 22 is rotatably disposed inside the rotor 22 through a predetermined air gap G, and the drive shaft 4 is attached to the end surface 23a of the end ring 23 at both the upper and lower ends of the rotor
An arcuate balance weight 5 is provided to protrude from the eccentric shaft portion 41 to balance the rotation.

Further, the cylinder 31 is equipped with a roller 34 that is eccentrically rotated by the eccentric shaft portion 41 of the drive shaft 4, and a muffler having a discharge port 36 is provided on the upper side of the front head 32. 35, and with the drive shaft 4 inserted into the roller 34, it is rotatably supported by the front and rear heads 32, 33, respectively.

In this manner, the refrigerant gas sucked into the cylinder 31 is compressed by the roller 34 by the rotation of the drive shaft 4 caused by the motor 2, and the compressed refrigerant gas is transferred to the cylinder 31. The muffler 35 is discharged into the muffler 35.
The discharged gas is discharged from the discharge port 36 into the primary space 6 formed between the motor 2 and the compression element 3, and the discharged gas is discharged into the air between the stator 21 and the rotor 22 in the motor 2. Through the gap G and the core cut H between the stator 21 and the inner wall of the casing 1, the motor 2 is guided to a secondary space 7 formed on the upper side of the motor 2, and from this secondary space 7 the He is trying to discharge it to the outside of the casing via the external discharge pipe 8 provided in the casing 1.

In the electric compressor described above, the balance weight 5 is formed by laminating a plurality of balance weight plates 51 made of arc-shaped thin plates along the end surface 23a of the end ring 23 as shown in FIG. At the same time, as shown in an enlarged view in FIG. In addition to being arranged in the length direction, these adjustment parts 53 are provided at the longitudinally intermediate portion and at positions symmetrical with respect to the intermediate portion. Furthermore, the size of the cutout area of these balance adjustment parts 53 is such that the weight when all of them are cut out is 50% of the total weight of the balance weight plate 51, and the size of each of the balance adjustment parts 53 is The size is set so that the weight loss when cut is divided into five levels ranging from 10% to 50%.

Specifically, for example, the balance weight 5 on the upper side of the rotor 22 will be explained. The balance weight plate 51 shown in FIGS. 1 to 3 is a thin plate having a semicircular arc shape. The balance weight 5 is formed by laminating five plates, and each balance weight plate 51 is formed by punching out a thin plate using a press, and when punched out from this thin plate, the whole becomes circular, and is interrupted by supporting parts 52a. At the same time, the slit 52 is formed, and the balance adjusting portion 53, which can be cut out, is formed inside the circular slit 52. That is, this balance adjustment part 53 forms a first balance adjustment part 53a having a size corresponding to 10% of the total weight at the middle part of the balance weight plate 51 in the arc length direction,
A second balance adjustment part 53b and a third balance adjustment part 53 having a size corresponding to 20% of the total weight in the arc length direction are located in bilaterally symmetrical positions with respect to the first balance adjustment part 53a.
The support portion 52a of the slit 52 forming the first, second, and third balance adjustment portions 53a, 53b, and 53c is cut to form the balance adjustment portions 53a, 53b, and 53c. When you cut out all the
The weight of the balance weight plate 51 is set to be 50% of the total weight.

Therefore, according to the balance adjustment section 53 formed as described above, as shown in Table 1, by selecting the balance adjustment section 53 to be cut out, the total weight can be adjusted to 10, 20, 30, 40, This means that it can be reduced to 5 stages of 50%.

In Table 1, the weight of the single balance weight plate 51 is 10g, the weight of the first balance adjustment section 53a is 1g, and the weight of the second and third balance adjustment sections 53b, 53 is 1g.
The weight of c is 2g.

In this way, one balance weight plate 5
1 can reduce weight by 10-50%,
For example, by using two balance weight plates 51, the weight of the balance weight 5 can be adjusted within the range of 1 g to 10 g in units of 1 g, and the weight of the balance weight 5 can be adjusted within the range of 1 g to 10 g. It can be adjusted.

[0020]

[Table 1]

That is, the balance weight plate 5 weighing 10 g
When forming the balance weight 5 of 50 g by stacking five sheets of 1.1, two of the balance weight plates 51 are used to form the first balance adjustment part 53a of 1 g.
and 2g of the second and third balance adjustment sections 53b and 5.
When adjusting the mass using four 3c, Table 2
As shown in the figure, it can be adjusted in units of 1 g. In addition, the numbers in Table 2 are for each balance adjusting section 53a, 53b, 5.
It represents the cut weight of 3c.

[0022]

[Table 2]

Note that 54 is a mounting hole for mounting the balance weight 5 to the end ring 23.

[0024] Thus, when forming the balance weight 5 by laminating a plurality of balance weight plates 51 made of arc-shaped thin plates, the balance weight plates 51 are surrounded by intermittent slits 52 and can be cut out. By forming a plurality of balance adjustment parts 53, it is possible to prevent the case where the diameter of the eccentric shaft part 41 of the drive shaft 4 changes and the capacity of the cylinder chamber of the compressor changes, or the length of the drive shaft 4 changes. When the dynamic and static balance changes such as when the balance amount by the balance weight 5 changes, the balance can be adjusted by simply cutting out the balance adjustment part 53 without having to provide many types of balance weight plates 51. weight 5
The mass can be adjusted. Therefore, all of the balance weight plates 51 can be formed using the same mold, and the balance weight 5 can also be easily adjusted by simply cutting out the adjustment portion 53.

Moreover, the balance adjustment portions 53 of the balance weight plate 51 are arranged in the arcuate length direction of the balance weight plate 51, and the balance adjustment portions 53 are arranged at the intermediate portion in the longitudinal direction and at the intermediate portion. On the other hand, by providing the balance adjustment parts 53 at symmetrical positions, it is possible to reduce the deviation of the center of gravity of the balance weight 5 even if the balance adjustment parts 53 are cut out. The weight when cut is 50% of the total weight of the balance weight plate 51, and each of the balance adjustment parts 53a, 53b,
The weight reduction when cutting out the size of 53c is 10 ~
The first balance adjustment section 53a and the second and third balance adjustment sections 53b have different sizes so as to have five levels of 50%.
, 53c, the balance adjustment parts 53a, 53b, 53c can perform stepwise and fine mass adjustment.

Therefore, the dynamic and static balance may change if the diameter of the eccentric shaft portion 41 of the drive shaft 4 changes and the capacity of the cylinder chamber of the compressor changes, or if the length of the drive shaft 4 changes. When the amount of balance by the balance weight 5 changes, the balance weight 5 of a predetermined mass can be formed with one type of balance weight plate 51 by simply cutting out the balance adjustment part 53, and yet,
It is possible to finely adjust the amount of balance within the weight range of one balance weight plate 51.

In the above-described embodiment, adjustment was performed using only two balance weight plates 51, but in order to further reduce the influence of positional deviation of the moment of the balance weight 5, two or more balance weight plates 51 are used. The balance amount may be adjusted using the weight plate 51.

Further, the balance adjustment sections 53 may all be formed to have the same size, or three or more may be formed. However, in order to reduce the influence on the position of the moment of the balance weight 5, the number of the balance adjustment parts 53 is preferably formed symmetrically with respect to the center of the balance weight plate 51 in the arc length direction. preferable.

[0029]

Effects of the Invention As explained above, in the electric compressor of the present invention, the balance weight plate 51 made of an arc-shaped thin plate
When forming the balance weight 5 by laminating a plurality of sheets, a plurality of balance adjustment parts 53 surrounded by intermittent slits 52 and made cuttable were formed on the balance weight plate 51. 53, the diameter of the eccentric shaft portion 41 of the drive shaft 4 changes and the capacity of the cylinder chamber of the compressor changes, or the length of the drive shaft 4 changes. When the static balance changes and the amount of balance by the balance weight 5 changes, the weight can be adjusted by simply cutting out the balance adjustment part 53 without providing many types of balance weight plates 51. Therefore, while the balance weight plates 51 can all be formed using the same mold, the balance weight 5 can also be easily adjusted by cutting out the adjustment portion 53.

Moreover, the balance adjustment portions 53 of the balance weight plate 51 are arranged in the arc length direction of the balance weight plate 51, and the balance adjustment portions 53 are arranged at the intermediate portion in the longitudinal direction and at the intermediate portion. On the other hand, by providing the balance weights 5 at symmetrical positions, even if the balance adjustment section 53 is removed, the shift in the center of gravity of the balance weight 5 can be reduced.

Furthermore, the balance adjustment section 53 is sized so that the weight when all the balance adjustment sections 53 are cut out is 50% of the total weight of the balance weight plate 51, and each of the balance adjustment sections 53 and ... were formed so that the weight reduction when cut out is in five stages of 10 to 50%. You can make fine adjustments step by step.

[Brief explanation of the drawing]

FIG. 1 is a perspective view showing a balance weight of an electric compressor of the present invention.

FIG. 2 is an enlarged plan view of the main part of FIG. 1;

FIG. 3 is a plan view of the rotor of the electric compressor of the present invention.

FIG. 4 is a longitudinal sectional view showing the overall structure of the electric compressor of the present invention.

FIG. 5 is an explanatory diagram showing a conventional example.

[Explanation of symbols]

1 Sealed casing 2 Motor 22 Rotor 3 Compression element 5 Balance weight 51 Balance weight board 52 slit 53 Balance adjustment section

Claims (3)

[Claims] 1. An electric compressor in which a motor 2 and a compression element 3 are housed in a sealed casing 1, and a balance weight 5 is provided at an end of a rotor 22 of the motor 2, wherein the balance weight 5 is arranged in an arc shape. The balance weight plate 51 is formed by laminating a plurality of balance weight plates 51 made of thin plates, and the balance weight plate 51 is surrounded by intermittent slits 52 and has a plurality of balance adjustment parts 53 that can be cut out. Characteristic electric compressor. 2. A balance adjustment section 53 of a balance weight plate 51 is disposed in the arc length direction of the balance weight plate 51, and the balance adjustment section 53 is arranged between the longitudinal intermediate section and the intermediate section. The electric compressor according to claim 1, wherein the electric compressor is provided at symmetrical positions. 3. A balance weight plate 51 is provided with three balance adjustment parts 53 having different cutout areas, and the weight when all the sizes of these adjustment parts 53 are cut out is 50% of the total weight of the balance weight plate 51. The size of
The electric compressor according to claim 1 or claim 2, wherein the size of each of the balance adjusting portions 53 is such that the weight reduction when cut out is in five stages of 10 to 50%.