JPS6239528B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a method for manufacturing a molded winding in which an axial end of a low-voltage laminated winding formed by winding a conductor is coated and solidified with a resin.

In general, in a stratified winding in which a conductor such as a strip is wound together with an interlayer insulator that protrudes in the axial direction from the conductor, the end of the winding tends to be a weak point against the axial mechanical force when a transformer is short-circuited. It is well known that the ends of the wire are filled with synthetic resin or the like to improve mechanical and electrical strength.

In this case, inner and outer leads that are in contact with the innermost layer of the winding and the inner leads led out from the layer, and the outermost layer of the winding and the outer leads led out from the layer, and that protrude further in the axial direction than the interlayer insulator. It has already been proposed to provide two guide tubes and use the two guide tubes as molds to cast resin onto the axial ends of the winding.

FIG. 1 is a plan view of a stratified winding. The innermost layer and the outermost layer of a stratified winding 3 are formed by overlapping a strip conductor 1 and a wider interlayer insulator 2 and winding them multiple times. Leads 4 and 5 are led out. A guide tube 6 is provided in contact with the inside of the winding 3 and the lead 4, and a guide tube 7 is provided in contact with the outside of the winding 3 and the lead 5.

The width of leads 4 and 5 is narrower than the width of conductor 1;
Therefore, in order to make the current density almost equal to that of the conductor 1, the thickness is increased, so that gaps 8, 8', 9, 9' is generated. In particular, the gaps 8 and 9 on the side not connected to the conductor are large.

In FIG. 2, which shows a cross section along the line A-A in FIG. 1,
The same reference numeral indicates the same thing as the previous one or something that has the same effect. The same applies below.

The axial end of the winding 3 is filled with resin 10 as described above. The conventional method for filling this type of resin is to first close the gaps 8, 8', 9, and 9' to prevent the resin from leaking, and then pour the resin in the container between the guide tubes 6 and 7 from above. do. After the resin has solidified, usually after 3 to 4 hours have elapsed, the winding 3 is turned upside down and the resin is cast onto the other end of the winding in the same manner as described above.

For this reason, the conventional casting method requires a lot of man-hours,
There were drawbacks such as the long manufacturing period and the need to work with the winding former in place, resulting in a poor turnover rate of the winding former.

SUMMARY OF THE INVENTION An object of the present invention is to provide a method for manufacturing a molded winding wire, which eliminates the above-mentioned drawbacks, requires fewer man-hours, shortens the manufacturing period, and allows a good rotation rate of the winding form.

In order to achieve this objective, in the present invention, resin is poured into the upper and lower ends of the winding in the gap 8,
8', 9, and 9' are arranged along the leads and open at the lower end of the winding, and at the same time, a resin-casting pipe is placed approximately in the center of the width of the winding, protruding from the lower end of the winding. A barrier is rolled up so that its tip is in contact with the bottom plate of the injection mold which is in contact with the lower ends of both guide tubes 6 and 7, and this barrier is spaced at a symmetrical position with respect to the opening of the resin casting pipe and the center of the winding. Roll it up and place it like this, and then press-fit the resin from the resin casting pipe.

The resin flowing out from the opening at the lower end of the winding is divided into two directions along the barrier in the space below the winding partitioned by the barrier, and flows upward through the gap. The resin flows in two directions along the barrier, and flows while expelling air to the gap between the opening and the barrier, which is located symmetrically with respect to the center of the winding, flows out from this gap, and is split in two directions again. , is pushed up to the top of the winding through the lateral gaps of the leads.

FIG. 3 is a diagram for explaining the present invention, in which the winding 3
Inner and outer guide tubes 6 and 7 provided across the
The lower end of is placed tightly on the bottom plate 31 via the packing 32. Then, a casting pipe 33 made of an insulator, the upper part of which is directly connected to a casting device (not shown), is inserted into one of the gaps on the side of the lead, and its lower end is used as a casting opening near the bottom of the winding. Press in.

The casting resin 10 is first filled into the lower end of the winding, then passes through the gap on the side of the lead, reaches the upper end of the winding, and is cast in the required amount. After the resin has solidified, the casting pipe 33 is filled.
is cut off at the surface of the resin 10.

Therefore, there is no need to cast the resin in two parts as in the past, and there is no need to close the gaps on the sides of the lead.
There is no need to wait for the resin to solidify or turn the winding wire upside down, which not only greatly reduces the number of man-hours, but also has the advantage of shortening the manufacturing period and improving the turnover rate of the winding form.

In this case, it is fine if the inner and outer leads come out from opposite sides to the center of the winding, but special consideration is required if the inner and outer leads come out from the same side of the winding, as is generally the case. It is.

That is, a small amount of air between the protrusions of the lower interlayer insulator 2 of the winding is pushed by the water head of the resin and escapes upward through the minute gap between the conductor 1 and the interlayer insulator 2. However, a considerable amount of air is forced into the lower end of the winding on the opposite side of the casting pipe by the resin from the casting spout, and the resin cannot escape from the tiny gap between the conductor and the interlayer insulator, preventing the resin from being cast and fills the cavity. may occur.

FIGS. 4 and 5 show an embodiment according to the present invention which also compensates for this drawback, in which a barrier 41 is wound around the lower end of the winding approximately in the center of the winding width for approximately one circumference. The lower ends of the guide tubes 6 and 7 are projected so as to come into close contact with the bottom plate when the lower portions thereof are placed on the bottom plate 31, and a gap portion 51 is formed on the barrier at a position symmetrical to the casting hole with respect to the center of the winding. Leave it open.

The resin from the casting pipe 33 flows along the barrier 41 to one side of the lower end of the winding (inner diameter side in the figure) as shown by the arrow, moves to the other side of the winding width from the gap 51, and flows into the casting pipe. 33, the lower end of the winding is filled. In other words, the air at the lower end of the winding is pushed by the resin and pushed out along the barrier 41, leading to the lead 5.
Since it escapes upward from the side gaps 9, 9', there is no risk of creating the above-mentioned cavity. In FIG. 5, the casting pipe 33 is placed on the side of the inner lead, but the above-mentioned effect will be the same even if it is placed on the side of the outer lead. According to the present invention, it is possible to manufacture a molded winding wire with fewer man-hours and a shorter manufacturing period than in the past, and with a good rotation rate of the winding form. In addition, according to the present invention, compared to filling the resin by pouring it from the top of the winding in the atmosphere, the path in contact with the air is shorter, so air is not drawn into the resin and a homogeneous casting resin can be obtained. Since the gaps between the sides of the leads 4 and 5 and the windings 3 and guide tubes 6 and 7 are filled with resin, there is an advantage that the leads are securely fixed.

[Brief explanation of the drawing]

FIG. 1 is a partial plan view of a mold winding, FIG. 2 is a vertical sectional view, FIG. 3 is a vertical sectional view for explaining the present invention, and FIG. 4 is a partial plan view of a mold winding according to an embodiment of the present invention. 5 is a plan view of the molded winding of FIG. 4; FIG. 1... Conductor, 2... Interlayer insulator, 3... Winding wire,
4, 5...Lead, 6,7...Guide tube, 10...
...resin, 31...bottom plate, 33, 63...casting pipe, 41...barrier, 61...casting port.

Claims (1)

[Claims] 1. Providing inner and outer guide tubes that are in contact with the inner and outer radial surfaces of the stratified winding from which leads are led out in the axial direction along the winding surface from the ends and the leads and that protrude from both end surfaces of the winding, After placing the lower ends of both guide cylinders containing the wires tightly on the bottom plate, resin is press-fitted through the casting hole that opens near the lower end of the winding, and the resin is poured from the lower end of the winding to the sides of the lead. Manufacture of molded winding in which resin is pushed up to the upper end of the winding through the gap formed between the winding and the side of the lead and the guide tube, and then hardened to cover both ends of the winding with resin. In the method, a resin-casting pipe is disposed in the gap along the lead and opens at the lower end of the winding, and at approximately the center of the width of the winding, the pipe protrudes beyond the lower end of the winding and its tip touches the bottom plate. A method for manufacturing a molded winding, characterized in that a barrier is wound in contact with the center of the winding at a position symmetrical to the opening of the resin casting pipe at a distance, and resin is press-fitted from the resin casting pipe.