JPH0246319A - Insulating coupling for rotating electric machine shaft - Google Patents

Abstract

PURPOSE:To increase a transfer torque for a coupling device of a revolving electric machine by arranging the thickness of an insulating cylinder that is in a region of shrinkage fit between an external cylinder and an internal cylinder differred in a direction of a joint axis. CONSTITUTION:An insulating cylinder 4 is arranged between an external cylinder 1 and an internal cylinder 3 of an insulating coupling in order to be electrically insulating. After the insulating cylinder 4 is baked on a periphery of the internal cylinder 3, it is peripheral-processed, and the external cylinder 1 is shrunk and fitted thereto, and then, the coupling is shrunk and fitted to an axis of a revolving electric machine. The thickness of the insulating cylinder in a portion A, a side of internal circumference of the external cylinder 1 of low contractive rigidity is defined thinner as t2<t1, compared to a portion B of intensive rigidity. The shrinkage fit surface pressure of portion A is increased, and the surface pressure of the portions A and B becomes almost the same as a result. In this way, the increase in a transfer torque can be achieved.

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to an insulating coupling having a shaft insulating function for a rotating electric machine, and particularly to a coupling structure suitable for transmitting excessive shaft torque.

[Conventional technology]

Conventionally, the so-called "container" has an electrical insulation function.

Insulating couplings can be made by placing insulating plates on the mating surfaces of the couplings and using insulating bolts, or by making the coupling into three parts: an inner body, an intermediate body, and an outer body. There was a method in which the insulating material was used, and the connection was made with bolts through a flange provided on the outer body.

(Mechanical Engineering Handbook (edited by the Japan Society of Mechanical Engineers) “Elements of Machines” P7
-61 Fig. 103) [Problems to be Solved by the Invention] In the conventional insulating coupling, the outer cylinder has a flange for bolting to the mating joint, which causes uneven thickness of the cylinder. Another problem is that the shrinkage rigidity during shrink fit is non-uniform, which causes differences in the strength and weakness of the surface pressure on the shrink fit surface.

In this case, in order to obtain the overall required transmission torque, it is necessary to take measures such as increasing the shrink fit interference or increasing the dimensions of the coupling to increase the area of the shrink fit part. This has been an obstacle in determining coupling dimensions.

The purpose of the present invention is to eliminate the uneven strength of the surface pressure due to the difference in rigidity due to the difference in the thickness of the outer cylinder, and to increase the transmitted torque by equalizing the surface pressure to the same level as the strong surface pressure section. It is in.

[Means to solve the problem]

The above object is achieved by changing the thickness of the insulating cylinder disposed between the outer cylinder and the inner cylinder of the coupling.

[Effect]

The insulating cylinder of the insulating case ring is inserted between the outer cylinder and the inner cylinder, and is compressed by the tightening allowance.If the thickness of the insulating cylinder is made thinner, the thickness of the insulating cylinder itself will be reduced at the same tightening allowance. The amount of directional compression is also reduced.

In other words, the reduction in thickness increases the reaction force against compression of the insulator, which acts to increase the contact pressure during shrink fitting.

[Example] An example of the present invention will be described below with reference to FIGS. 1 and 2. In FIG. 1, 1 is an outer cylinder of an insulating coupling, 2 is a bolt hole for connection with a coupling partner, 3 is an inner cylinder of the same, 4 is an insulating cylinder, 5 is an inner circumferential surface of the inner cylinder, and Each figure shows the shrink fit surface with the rotating electric machine shaft.

In this insulated coupling, the parts that transmit shaft torque are the rotary electric machine shaft and the inner circumferential shrink-fit surface of the coupling, between the inner cylinder and the insulating cylinder, between the insulating cylinder and the outer cylinder, and the coupling bolt of the outer cylinder. The assembly method is usually performed in the following order: after baking the insulator onto the outer periphery of the inner cylinder, processing the outer periphery, shrink-fitting the outer cylinder to it, and then shrink-fitting the coupling to the shaft of the rotating electrical machine. It is true.

The magnitude of the transmitted torque is proportional to the magnitude of the surface pressure of the shrink fit portion. In addition, the distribution of surface pressure depends on the shrinkage rigidity of the shrink-fitted body, and since the stiffness of portions A and B of the coupling outer cylinder 1 is A<B, the surface pressure after shrink-fitting is It goes without saying that if the thickness of 4 is uniform, the surface pressure of portion A will be smaller than that of portion B.

Therefore, the possible transmission torque at the coupling shrink fit surface is A
This is the sum of the 8-part transmission torque and the 8-part transmission torque, and it has been difficult to obtain a uniform and high-level transmission torque in the shrink-fit area.

According to this embodiment, the thickness of the insulating cylinder on the inner circumferential side of the outer cylinder of part A, which has low shrinkage rigidity, is made thinner than that of part B, which has higher rigidity, such that t2<tl. The surface pressure increases, and as a result, the surface pressures at portions A and B become approximately equal, resulting in a uniform-high level surface pressure characteristic as shown in FIG.

〔Effect of the invention〕

According to the present invention, high transmission torque characteristics can be ensured without increasing the overall dimensions of the insulating coupling, so it is possible to provide a rotating electric machine with high resistance to transient shaft torque.

[Brief explanation of the drawing]

FIG. 1 is a sectional view of an insulating coupling according to an embodiment of the present invention, FIG. 2 is a surface pressure distribution diagram on the shrink fit surface of FIG. 1, and FIG. 3 is a sectional view of a conventional insulating coupling. FIG. 4 is a surface pressure distribution surface of the shrink-fit surface shown in FIG. 1... Coupling outer cylinder, 2... Coupling bolt hole, 3... Coupling inner cylinder, 4... Insulating cylinder, 5
...Inner peripheral surface of the inner cylinder of the coupling, 6...Axle of the rotating electric machine. factor diagram

Claims (1)

[Scope of Claims] 1. Consisting of an outer cylinder and an inner cylinder, an insulating cylinder for electrical insulation is arranged between the outer cylinder and the inner cylinder, and after they are shrink-fitted to each other, the rotary electric machine In a shaft coupling device for a rotating electric machine, which is attached to a shaft and the mating shaft coupling is a shaft coupling device for a rotating electrical machine in which torque is transmitted by bolts arranged on a flange of the outer cylinder, the shrink fit range between the outer cylinder and the inner cylinder. An insulating coupling for a shaft of a rotating electrical machine, characterized in that the thickness of the insulating cylinders is arranged to vary in the direction of the joint shaft.