JPH0218686Y2 - - Google Patents

Description

[Detailed Description of the Invention] This invention relates to a short circuit device for a wound induction motor.

FIG. 1 is a side view showing a conventional short-circuit device for a wound induction motor, and FIG. 2 is a perspective view showing the support frame of FIG. 1. 1 and 2, the shorting ring 1 is provided with a plurality of contacts 24 at one end,
It is composed of a cylindrical portion 101 and a pair of collar portions 102 and 103 attached to both ends of the cylindrical portion 101. The shaft 2 is inserted through the cylindrical portion 101 and supports the shorting ring 1 so as to be slidable in the direction of arrow A. The slip ring 3 is attached to one end of the shaft 2, has a brush 22 in contact with its outer periphery, and has a plurality of contacts 2 provided facing the contacts 24.
It has 3. The adapter 11 houses a short circuit device, and has an upper frame 401 fixed to its upper part with bolts 12, and a support member 10 fixed to its lower part with bolts (not shown). Further, a crankshaft 21 is supported by the adapter 11, a handle 20 is attached to the outside, and a short-circuit crank 9 is attached to the inside. The support frame 4 has a lower frame 40 as shown in FIG.
2 and both side frames 403, 404, and both side frames 403, 404 are connected to a pair of pins 5.
It is rotatably supported in the direction B by the upper frame 401 by a and 5b. A pair of bearings 6a, 6b
are supported rotatably in the D direction on the inner surfaces of both side frames 403 and 404, and the pair of collar portions 1 of the shorting ring 1
It is slidably engaged with either side of 02 or 103. The middle part of the lever 7 is the lower frame 4 of the support frame 4.
It is fixed at 02. first and second rollers 8a,
8b is rotatably attached to both ends of the lever 7. The short-circuit crank 9 has a spiral groove 901 that is screwed into the first roller 8a, and is configured to be rotatable together with the handle 20. The support member 10 rotatably supports the second roller 8b.

The crankshaft 21 is arranged on the center line of the bearings 6a, 6b, and the groove 10a of the support member 10 is also formed in the axial direction (direction A) on the same center line. Furthermore, since the widthwise center of the upper frame 401 and the widthwise center of the lever 7 are located on the same center line, the rollers 8a and 8b are configured to always move on the same center line when the support frame 4 moves. has been done.

A secondary resistor (not shown) connected between the brushes 22 is provided outside the wound induction motor. One end of each phase ring of the slip ring 3 is connected to the rotor winding, and the other end is connected to the contactor 23 of each phase. The plurality of contacts 24 are short-circuited to each other.

When starting a wound induction motor, the shorting ring 1 is separated from the slip ring 3 as shown by the chain line in Figure 1, and the secondary current flows through the secondary resistor via the brush 22, and the motor starts. . After starting, when the motor reaches the rated speed, bring the shorting ring 1 closer to the slip ring 3 side, and connect both contacts 2 which are far apart.
3 and 24 are brought into contact to short-circuit the current flowing through the secondary resistor via both contacts 23 and 24. Thereafter, the electric motor is operated at the rated speed in this state. When stopping the motor, separate the shorting ring 1 from the slip ring 3 side.

Next, the operation of the shorting device will be explained in detail. Now, when the handle 20 is rotated in one direction, the short-circuit crank 9 is rotated in the same direction, and the first roller 8a screwed into the spiral groove 901 is rotated by the bearing 6a.
6b on the center line in the right direction in FIG.
It rotates counterclockwise around a and 5b. Therefore, the pair of bearings 6a and 6b
The short-circuiting ring 1 is slid to the right as shown by the solid line in FIG. 1, and both contacts 23 and 24 are brought into contact with each other to short-circuit the secondary circuit. Next, when the short circuit crank 9 is rotated in the other direction, the first roller 8a moves to the left in FIG. 1, and the support frame 4 moves clockwise around the pair of pins 5a and 5b shown in FIG. Rotate to. Therefore, the pair of bearings 6a and 6b abut against the collar 102, and the shorting ring 1 is slid to the left as shown by the dashed line in FIG. 1 to separate the contacts 23 and 24 from each other. Make the secondary current flow through the external secondary resistor.

Since the conventional device is configured as described above, when the short-circuit crank 9 rotates, the first roller 8a does not contact the wall surface of the spiral groove 901 perpendicularly, but contacts it diagonally, so that A Receives a component force other than the direction,
Even if the second roller 8b restricts the movement on the center line of the bearings 6a, 6b, the first roller 8b
When a receives the above component force, the first roller 8
A twisting force acts on the lever 7 and the lower frame 402 of the support frame 4, which are coupled to the lever 7a. Due to this torsional force, the entire support frame 4 is twisted, and the pair of bearings 6
Only one of a and 6b is slidably engaged with either side of the brim portions 102 and 103 of the shorting ring 1, and the other is not slidably engaged, and an unbalanced force is applied to the shaft 2. There was a drawback that the space between the shorting rings 1 was mechanically restricted.

In such a case, if the support frame 4 is rotatable in the C direction, the pair of bearings 6a and 6b will be balanced and come into contact with the brim of the shorting ring 1, which will eliminate this drawback. The one in Figure 2 does not have this kind of structure.

This invention was made in order to eliminate the drawbacks of the above-mentioned conventional ones. An embodiment of this invention will be described below with reference to the drawings.

FIG. 3 is a perspective view showing an embodiment of the main parts used in the short circuit device according to the invention. In the figure, the first
The same parts as in FIG. 1 and FIG. 2 are given the same reference numerals. Note that the support frame 4 shown in FIGS. 1 and 2 will be referred to as an inner frame 4. In the figure, the fixed frame 13
1 is fixed to an adapter 11 with a bolt 12.

The outer frame 13 includes an outer lower frame 132 and outer both side frames 13
3,134, and the outer lower frame 1
An intermediate portion of the lever 7 is fixed to the lever 32 on the center line of the bearings 6a and 6b. Also,
The outer lower frame 132 has a pin 15 on the opposite side of the lever 7.
is fixed perpendicularly to the lever 7. Outer frame 1
3 is supported by the fixed frame 131 by pins 16a and 16b so as to be rotatable in the B direction. For this reason,
When the outer frame 13 rotates, the rollers 8a, 8b and pin 1
5 moves in the direction A while drawing an arc on the same center line.

The fixed frame 131 is provided with a bolt/nut 14 for position adjustment and support on the center line of the bearings 6a, 6b.
is attached, and due to this play, the upper frame 401 can rotate slightly in the direction C using G as a fulcrum.

The inner frame 4 includes an inner lower frame 402 and inner both side frames 403,
404. Upper frame 40
1 is provided with pins 5a and 5b, and the inner frame 4 is rotatable in the direction B using the pins as fulcrums. The inner lower frame 402 is supported at one point so that it can move in the C direction using the pin 15 as a fulcrum, and therefore the inner frame 4 and the upper frame 401 are connected to the pin 15 and the bolt
The nut 14 is supported at two support points G and rotated in the C direction. Also, the bearings 6a and 6b are connected to the inner side frames 40 as in FIG.
3,404.

Next, the operation will be explained with reference to FIG. 3 and FIG. Now, when the short circuit crank 9 is rotated in one direction by rotation of the handle 20, the first roller 8a moves to the right in FIG.
It rotates counterclockwise in FIG. 1 about a and 16b. Due to this rotation, the inner frame 4 also
5, the shorting ring 1 rotates counterclockwise in FIG.
Slide it to the right as shown by the solid line in Figure 1,
Both contacts 23 and 24 are brought into contact to short-circuit the secondary circuit.

Next, when the short circuit crank 9 is rotated in the other direction, the first roller 8a moves to the left in FIG. 1, and the outer frame 13 moves clockwise in FIG. 1 around the pair of pins 16a and 16b. Rotate. Due to this rotation, the inner frame 4 also connects the pair of pins 5 via the pins 15.
a and 5b in the clockwise direction in FIG. 1, and as in FIGS. 1 and 2, slide the shorting ring 1 to the left as shown by the dashed line in FIG. The terminals 23 and 24 are separated to open the external secondary resistor.

In this embodiment, the inner frame 4 and the upper frame 401 are connected by a pair of pins 5a and 5b, and the inner frame 4
and upper frame 401, outer frame 13, and fixed frame 131
Since it is rotatably supported in the C direction by a pin 15 and a bolt/nut 14 located on the center line of the bearings 6a and 6b, the first roller 8a moves into the spiral groove when the short-circuit crank 9 rotates. The torsional force based on the component force in directions other than the A direction received from 901 is only received by the outer frame 13 and is not transmitted to the inner frame 4. Therefore, both bearings 6a and 6b can contact the collar of the shorting ring 1 in a free state, and there is no mechanical restraint between the shaft 2 and the shorting ring 1 as in the conventional case, and the shorting ring 1 can be moved smoothly.

As described above, according to this invention, the inner frame, which is the source of moving the short circuit ring by the rotation of the short circuit crank, and the upper frame connected thereto, are connected to the bearing 6a by the outer frame 13 and the fixed frame 131. , 6b so that it can move freely at two points on a straight line passing on the center line of the short-circuit ring, the pair of bearings that move the short-circuit ring do not biasly contact the short-circuit ring, and the short-circuit ring can be moved smoothly.

[Brief explanation of the drawing]

Fig. 1 is a side sectional view showing a conventional short-circuit device for a wound induction motor, Fig. 2 is a perspective view showing the main part of Fig. 1, and Fig. 3 is an implementation of the main part of the short-circuit device according to this invention. It is a perspective view showing an example. In the figure, 1 is a short circuit ring, 101 is a cylindrical part,
102 and 103 are a pair of brim parts, 2 is a shaft, 4 is an inner frame, 401 is an upper frame, 402 is an inner lower frame, 403,
404 is an inner side frame, 5a and 5b are a pair of pins,
6a and 6b are a pair of bearings, 7 is a lever, 8
a, 8b are first and second rollers, 9 is a short circuit crank, 901 is a spiral groove, 10 is a support member, 10a is a groove, 11 is an adapter, 12 is a bolt, 13 is an outer frame, 131 is a fixed frame, 132 is the outer lower frame, 13
3, 134 are outer side frames, 14 is a bolt/nut, 15 is a pin, 16a, 16b is a pair of pins,
20 is a handle, 21 is a crankshaft, 22 is a brush, and 23 and 24 are contacts. Note that the same reference numerals in the figures indicate the same or corresponding parts.

Claims (1)

[Scope of utility model registration request] A short-circuiting ring that is capable of short-circuiting a secondary circuit of a wound-wound induction motor and that is composed of a cylindrical part and a pair of collar parts attached to both ends of the cylindrical part, and that short-circuits or opens the secondary circuit. ,
A shaft that is inserted through the cylindrical portion and slidably supports the short circuit ring, a fixed frame fixed to the adapter, an upper frame rotatably supported at one point on the fixed frame, an inner lower frame and inner both side frames. A pair of bearings are integrally formed with the inner side frames, the inner side frames are rotatably supported by the upper frame via pins, and the bearings are slidably engaged with the collar portion. An inner frame supported by both side frames, an outer lower frame supporting the inner lower frame at one point so as to be rotatable in the same direction as the upper frame via a pin, and the outer both sides frames, and an outer frame in which both outer side frames are rotatably supported by the fixed frame via pins in the same direction as the rotational direction of the inner both side frames; a lever having an intermediate portion fixed to the outer lower frame; first and second rollers attached to both ends of the lever; a short-circuit crank that has a spiral groove that screws into the first roller and is rotatably supported by the adapter; and a short-circuit crank that is fixed to the adapter. A short-circuit device for a wound induction motor, comprising a supporting member rotatably supporting the second roller.