JPS61248925A - Brake device of rotary electric machine - Google Patents

Abstract

PURPOSE:To optimize slide pressure distribution and prevent the roughening, breakage, and abnormal abrasion of a brake shoe by constituting the brake shoe with its center position displaced from the support center position of a piston toward the rear side in the rotating direction of a brake ring. CONSTITUTION:A brake shoe 1 is formed so that the center Cp of the piston 4 of a cylinder 3 operated via the air pressure is displaced by (e) from the center Cb of the effective length lo in the sliding direction of the brake shoe 1 toward the rear side in the rotating direction of a brake ring 6. Thereby, slide pressure distribution is high at the front side in relation to the rotating direction and is gradually decreased at the rear side, thus the slide pressure at the rear side is suppressed. Accordingly, smooth braking without roughening, breakage, and abnormal abrasion of the brake shoe 1 can be performed even at a high speed.

Description

DETAILED DESCRIPTION OF THE INVENTION [Technical Field of the Invention] The present invention relates to Jl friction brake devices such as vertical water turbine power generators, and particularly relates to brake devices equipped with flat brake shoes.

[Technical background of the invention and its problems] A vertical water turbine generator is equipped with a brake device for braking the rotor.

This brake device has a plurality of fixed side seams arranged in parallel that face the lower end surface of a general C-rotor.

A flat plate plate is provided on the upper part of the cylinder part, and the rotor is braked by frictional force using the pressure of fluid such as air or oil.

To explain this with reference to FIG. 4, the central part of a flat brake shoe support 2 that supports the entire lower surface of the flat brake shoe 1 is inserted into a cylinder 3 and supported by an optical piston 4, and compressed air is supplied separately. Pressurized air is introduced from the device through the intake port 3a of the cylinder to push the piston 4 upward.

Reference numeral 5 indicates a restoring mechanism using the elasticity of a spring, and reference numeral 6 indicates a brake ring provided on the rotor.

However, such conventional brake devices have had problems in braking at high circumferential speeds. In other words, as water turbine generators increase in speed and capacity, the installation position of the brake device increases the circumferential speed, and the thrust bearings operate at low speeds. As a result, as shown in the braking pressure distribution C shown in Fig. Split part 6a of the mental brake ring
As a result, it has become difficult to achieve smooth braking, such as damage to the brake ring or brake ring, damage to the brake shoe, or abnormal wear of the brake shoe.

[Object of the Invention] An object of the present invention is to provide a brake device for a rotating electrical machine that can suppress the pressure on the rear side in the rotational direction of the brake shoe and perform smooth high-speed braking.

[Summary of the Invention] In order to achieve the above objects, the present invention (-) provides a rotor brake ring, a flat brake shoe that makes sliding contact with the brake ring, and a flat brake shoe that supports the brake shoe. In a brake device for a rotating electrical machine, which includes a support, a piston that supports a limited position on the lower surface of the brake shoe support, and a cylinder into which the piston is inserted, the center position of the brake shoe is determined. is shifted from the support center position of the piston to the rear side (-) in the rotational direction C of the brake ring, thereby suppressing the pressure on the rear side of the brake shoe.

[Embodiments of the invention] An embodiment of the present invention will be described below with reference to drawing ζ2.

FIG. 1 shows the brake device. In FIG. 1C, the same reference numerals are given to the apparatus shown in FIG.

To explain using each symbol added to this figure, CP indicates the center line of the piston 4, that is, the support center position of the brake shoe 1, and Cb indicates the center line of the effective length tQ of the brake shoe 1 in the sliding direction.

Here, the positional relationship between Op and Cb is such that Cb is on the rear side (deviated by a distance e) with respect to the rotational direction of the brake ring 6 compared to Cp I.

The sliding pressure distribution of the brake device configured in this way is the second
Added to the figure. As is clear from this figure, the rotation of the brake ring 6 of the C-brake shoe 1 has a distribution that is high in the front and gradually decreases toward the rear in one direction. In other words, the distribution state is completely opposite to that shown in FIG. Therefore, the sliding pressure on the rear side where rough damage and chipping are likely to occur is suppressed, thereby preventing defects and achieving smooth C: braking.

The above-mentioned deviation t- has an appropriate range. Fig. 3 C. Experiment showing the relationship between the ratio of the effective length tQ of the shoe to the distance t from the support center cP of the piston including the deviation ite to the rear end of the shoe, the braking friction coefficient f, and the temperature of the sliding surface. This is the result. As is clear from this figure, C ut/l (, is 0.53
~0.62. Preferably, it is 0.57 (if set to -, good results can be obtained.

"Effects of the Invention" According to the present invention, the support positional relationship between the brake shoe and the piston of the brake device is configured such that the center position of the brake shoe is shifted rearward from the support center position of the piston with respect to the rotational direction of the brake ring. Therefore, the sliding pressure on the rear side is suppressed and smooth braking is possible even at high circumferential speeds.

[Brief explanation of drawings]

FIG. 1 is a sectional view of a brake device showing an embodiment of the present invention, FIG. 2 is a sliding pressure distribution diagram of the brake device of FIG. 1, and FIG. 3 is for explaining the effects of the brake device of the present invention. FIG. 4 is a sectional view of a conventional brake device. 1... Brake shoe 2... Brake shoe support 3... Cylinder 4... Piston 6... Brake ring agent Patent attorney Noriyuki Chika (1 person) Figure 1 Figure 3

Claims (1)

[Claims] A brake ring of a rotor, a flat brake shoe in sliding contact with the brake ring, a flat brake shoe support that supports the brake shoe, and a piston that supports a limited position on the lower surface of the brake shoe support.
In a brake device for a rotating electrical machine including a cylinder into which the piston is inserted, the center position of the brake shoe is shifted rearward from the support center position of the piston with respect to the rotational direction of the brake ring. A brake device for a rotating electrical machine, characterized in that the sliding contact pressure distribution is gradually decreased from the front side to the rear side with respect to the rotational direction of a brake ring.