JPH0130094B2 - - Google Patents

Description

[Detailed description of the invention] The present invention relates to an eddy current electric dynamometer.

Figure 1 shows the cross-sectional structure of a conventional disk-shaped eddy current electric dynamometer. Shaft 1 connected to the part to be measured
Inductor (rotor) 102 attached to 01
Inner ring 1, which is sandwiched between both sides with a gap between
03 are attached to bracket 106 by spacing ring 104 and bolt 105, respectively.
Two brackets 106 are connected to both sides of yoke 107 with bolts 108. A coil 109 is located inside the yoke 107. 110 is a bearing support that is connected to the bracket 106 and is swingably supported; 111 is a swing bearing; 112 is a bearing support; and 113 is a water channel formed inside the inner ring 103.

By the way, in such a dynamometer, the bracket 106, yoke 107, and inner ring 103 are separate bodies, and because they are connected by bolts, there are many joint surfaces between the members, which act as air gaps and prevent the flow of magnetic flux. Furthermore, due to stacking errors due to the large number of bonding surfaces, it is difficult to achieve precision in the minute gap between the surface of the inductor 102 and the inner ring 103. Furthermore, since the inner ring 103 has a structure that only stops both the inner and outer edges thereof, the surface of the inner ring 103 is heated due to the passage of magnetic flux, and the inner ring 1
There is also a possibility that the center portion of the inner ring 103 may bulge and deform due to the magnetic attraction force acting on the inner ring 103. In this case, a situation such as leakage of cooling water may occur.

The present invention aims to improve the strength and accuracy of an eddy current electric dynamometer in order to eliminate the above-mentioned drawbacks. In order to achieve this object, the present invention has a structure in which a yoke is provided surrounding an inductor attached to a shaft to which a part to be measured is connected, and the yoke is rotatably supported with respect to the shaft. The present invention is characterized in that an inner ring having a water channel is formed integrally with the yoke so as to be close to a side surface of the inductor, and a coil is further disposed within the yoke on the outside of the inductor in the radial direction.

Hereinafter, one embodiment of the present invention will be described in detail with reference to the drawings.

FIG. 2 shows a half cross-sectional structure of one embodiment.

An inductor (rotor) 2 is attached to a shaft 1 to which a part to be measured (drive source, etc.) is connected, and a first yoke 3 and a second yoke 4, which are integrated, are attached to the shaft 1 surrounding this inductor 2. It is rotatably supported. The first yoke 3 and the second yoke 4 both have an annular shape and are integrally formed by casting. 1st yoke 3
An inner ring 3a having a water channel 5 therein is integrally formed therein, and a coil accommodating portion 3b having an L-shaped cross section for accommodating the coil 6 is formed on the outer peripheral side of the inner ring 3a. Similarly, the second yoke 4 is also integrally formed with an inner ring 4a having a water channel 5 therein, and a coil accommodating portion 4b is formed on the outer peripheral side of the inner ring 4a. A bonding surface 8 corresponding to the coil accommodating portion bonding surface 7 of the first yoke 3 is formed in the coil accommodating portion 4b. In addition,
The shape of the water channel 5 may be various, such as concentric or radial. First yoke 3 and second yoke 4
The joint surfaces 7 and 8 are joined together by a bolt 9. In addition, the inner rings 3a and 3b of each yoke 3 and 4 are located on the outer side near the inner side.
It is connected to a bearing support 10 which is positioned at a predetermined position relative to the inductor 2 and is swingable, and the surfaces (inside surfaces) of the inner rings 3a and 4a are close to the surface of the inductor 2. 11 is a bearing provided between the shaft 1 and the bearing support 10, 12 is a fixed pedestal, and 13 is a swing bearing. Inner ring 3 of each yoke 3, 4
A lid 15 having a water channel 14 for supplying and discharging cooling water to and from the water channel 5 is provided on the outside of a and 4a.

In this embodiment, the integrated yoke is divided at the intersection of the cylindrical part and the disc part, making both parts asymmetrical, but the division may be made anywhere; for example, by dividing the yoke at the center of the cylindrical part, both parts can be separated. It is also possible to have a symmetrical shape and flange connection at the joint. When the yoke is symmetrical, there is an advantage that only one type of mold is required.

As mentioned above, the eddy current type electric dynamometer of the present invention is made by integrating the conventional inner ring and bracket, or in addition to the yoke part to form two yokes, and joining these together, so that manufacturing is easy. It is easy to use, has significantly improved strength, and can prevent heating due to the passage of magnetic flux and deformation due to magnetic attraction. In addition, due to the reduction in the number of parts, the number of joint surfaces is reduced, and the air gap caused by the joint surfaces is eliminated, which improves the flow of magnetic flux and improves surface processing.
There is less bolt hole machining and manufacturing costs can be reduced. Reducing the number of joint surfaces also eliminates stacking errors and improves assembly accuracy. For example, it is possible to easily set a minute gap between the inductor and the inner ring. Furthermore, since the inner ring part can be integrally cast, it is also possible to make the heat generating part thinner and enhance the cooling effect.

[Brief explanation of drawings]

FIG. 1 is a half sectional view of a conventional eddy current electric dynamometer, and FIG. 2 is a half sectional view of an embodiment of an eddy current electric dynamometer according to the present invention. In the drawings, 1 is a shaft, 2 is an inductor, 3 is a first yoke, 4 is a second yoke, 3a, 4a are inner rings, 3b, 4b are coil housing parts, 5 is a waterway, 7,
8 is a joint surface, and 10 is a bearing support.

Claims (1)

[Claims] 1 A yoke is provided surrounding an inductor attached to a shaft to which the part to be measured is connected, the yoke is rotatably supported with respect to the shaft, and an inner ring having a water channel inside is placed close to the side of the inductor. An eddy current type electric dynamometer, characterized in that the eddy current electric dynamometer is formed integrally with the yoke, and further includes a coil disposed within the yoke radially outside of the inductor.