JPS6062847A - Grounding device of rotary machine - Google Patents

Abstract

PURPOSE:To providing a low contacting resistance equivalent to a silver brush and a current capacity equivalent to a carbon brush by engaging a conductor rod with a stud formed on a stationary frame of a rotary machine, mounting a slide contact piece at one end of the rod, and winding a spring on the stud. CONSTITUTION:A conductor rod 2 is loosely engaged with a stud 4a formed on a stationary frame 4 of a rotor. A slide contact piece 3 which is slidably contacted with a rotor shaft is mounted on one end of the rod 2. A spring 2b is wound on the stud 4a, and the both ends of the spring 2b are engaged with the rod 2 and the frame 4, respectively. A flat steel lead may be, for example, used for the piece 3.

Description

DETAILED DESCRIPTION OF THE INVENTION [Technical Field of the Invention] The present invention relates to a grounding device for preventing shaft voltage generated in a rotor of a rotating machine.

[Technical background of the invention and its problems]

Generally, in a rotating machine such as a rotating electric machine, a rotor/biaxial voltage is generated due to friction or the like. If this voltage is high, the oil film on the bearing that supports the rotor will break, causing damage to the bearing. For this reason, a grounding brush is usually provided on the rotor surface to suppress the shaft voltage. Conventionally, a silver brush or a carbon brush has been used as this grounding device. Silver brushes have low contact resistance but low current capacity.
On the other hand, the Toriki-Bon brush had the advantage and disadvantage of high contact resistance.

[Purpose of the invention]

An object of the present invention is to provide a grounding device for a rotating machine that has a contact resistance as low as a silver brush and a current capacity as high as a carbon brush.

[Summary of the invention]

In order to achieve the above object, the grounding device for a rotating electric machine of the present invention has a mounting hole in the center, and a conductor rod that is loosely fitted into the stand bifurcated from the fixed frame C of the rotating machine by the mounting hole. A sliding contact piece attached to one end of the conductor rod and slidingly contacting the rotor shaft; a frame wrapped around the stand and having both ends fixed to the conductor rod; and a spring hooked to the rotor shaft. Aim for good sliding contact with.

[Embodiments of the invention]

An embodiment of the present invention will be described below with reference to the drawings.

Fig. 1 shows a rotor grounding device according to the present invention (2), in which (1) shows the rotor shaft, and (2) shows a conductor rod for grounding the rotor shaft (1), and the tip thereof shows the rotor grounding device. Installed sliding contact piece (3
) Ground from In. (4) is an outer frame for attaching the conductor rod (2), and this may also be used as a bearing outer frame or the like.

The conductor rod (2) also has a mounting tube (2c) for attaching it to the outer frame (4), and a spring (2b) for pressing the sliding contact piece (3) against the rotor shaft (11). The other end is equipped with an insulating handshake (2e) covered with an insulating cover.The straight part of the conductor rod (2) is also equipped with a cable (5) to connect the grounding current to the outside. Let it flow.

Furthermore, the surface of the stud (4B) to which the conductor rod (2) of the outer frame (4) is attached is covered with an insulator. Stud (4
Insert a split pin etc. into the tip of a).

In the grounding device for a rotating machine constructed in this way, the sliding contact piece (3) for the contact part to the rotor shaft (1) can be made of, for example, pure flat copper steel. It is possible to use something that has a contact resistance as low as a brush and a current capacity as high as a carbon brush. In addition, when inspecting or replacing, grasp the insulated handshake (2e) and pull up the spring (2b) for pressing.
a) It can be easily removed by pulling it out. In addition, this inspection and replacement work can be performed while the rotary machine is in operation, since the insulation is sufficient.

〔Effect of the invention〕

As described above, according to the present invention, the silver brush 11. It has the advantages of both carbon brushes and can be easily maintained, inspected, and replaced even during operation.

[Brief explanation of drawings]

Fig. 1 is a sectional view showing a rotor grounding device according to an embodiment of the present invention, Fig. 2 is an enlarged view of the main part of Fig. 1, Fig. 3 is a perspective view of a conductor bar, and Fig. 4 is an outer frame. FIG. 1...Rotor shaft, 2...Conductor rod, 2b...Spring, 2C...Mounting tube, 2d...S) 7 par, 2e...
...Insulated handshake, 2f...Cable, 3...Sliding piece, 4...Outer frame, 4a-Stud, 5...Cable. Agent Patent Attorney Noriyuki Chika (and 1 other person) Figure 1 2 / / Figure 4 Figure 2 Figure 3

Claims (1)

[Claims] There is a mounting hole in the center of the stand provided on the fixed frame of the rotating machine. What is claimed is: 1. A grounding device for a rotating machine, comprising a spring that is wound around the stand and has both ends hooked to the conductor rod and the fixed frame.