Molding method of bar wire with S bend at end part

Abstract

The invention relates to the technical field of generator manufacturing, in particular to a forming method for a wire rod wire with an S bend at the end. The invention aims to solve the difficulty caused by the S-bend special molded line at the end part of the bar in the lead molding process, and ensure the accuracy of the molded line and the size of the lead, thereby ensuring the performance of the bar. According to the method, the S-bend in the rising direction is formed, other molded lines on the outer side of the S-bend are formed, insulation wrapping can be carried out after the coil subjected to gelling and shaping is simply chamfered and cleaned, the wire produced through the method has the good molded lines, the good section size and the good geometric size, and the electrical performance of a wire bar subjected to insulation wrapping and pressing is effectively guaranteed.

Description

Technical Field

[0001] The present application relates to the field of generator manufacturing, and more specifically, to a method for forming a wire rod conductor with an S-bend at the end. Background Art

[0002] Variable speed pumped storage units are considered to be a promising development direction because they can effectively solve the problems of low efficiency of constant speed units when running at low heads, severe vibration wear and cavitation of the units, but the design of the rotor coil with an S-bend between the slot and the straight corner brings great difficulties to the forming of the wire rods and conductors. Summary of the invention

[0003] In view of the above problems, the present application proposes a method for forming a wire rod conductor with an S-bend at the end to solve the above problems; the operation is feasible, the forming line is accurate, and it can be used for mass production. Specifically, it is completed according to the following steps:

[0004] S1. Forming S-bend in the ascending direction: Design and manufacture the corresponding S-bend forming mold according to the product drawing requirements, wrap the demoulding material and tightening material around the outer side of the wire end that has been straight-lined and gelled, put the wire into the mold, align the center of the wire groove with the center of the groove on the mold, and use a special handle with an axis to bend the coil so that the coil is close to the forming axis at the corresponding corner of the mold to create the arc required by the drawing, and form the two arcs of the S-bend from the center of the coil to the outside.

[0005] S2. Form the remaining profile lines on the outside of the S-bend: After the S-bend is formed, replace the end forming die designed and manufactured according to the profile line, use the forming handle to rotate the corners of the S-bend and the rest of the outside along the forming axis, so that the coil is formed according to the mold profile line, and the forming is carried out in sequence from the inside to the outside;

[0006] S3, Gelatinization correction: Considering the metal rebound and the error caused by manual operation, the formed coil is placed in a hot pressing mold. The coil is pressurized by the mold during the coil pressing process to correct the deviation in the forming process.

[0007] The beneficial effects of the present invention are as follows: the coil forming profile is accurate, and the electrical properties of the entire wire rod after insulation are effectively guaranteed. BRIEF DESCRIPTION OF THE DRAWINGS

[0008] In order to more clearly illustrate the technical solutions in the embodiments of the present application, the drawings required for use in the description of the embodiments will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present application. For those skilled in the art, other drawings can be obtained based on these drawings without paying any creative work.

[0009] Figure 1A schematic diagram of the structure of an S-bend forming mold provided in an embodiment of the present application is shown;

[0010] Figure 2 A schematic diagram of an end forming die provided in an embodiment of the present application is shown;

[0011] Figure 3 A schematic diagram of a hot pressing mold provided in an embodiment of the present application is shown;

[0012] Figure 4 A schematic diagram of a wire rod with an S-bend at the end manufactured in an embodiment of the present application is shown;

[0013] Explanation of marks in the figure: 1-special handle, 101-molded restraining rod, 102-handle shaft, 103-bearing, 201-molded shaft close to the wire rod groove, 202-molded shaft away from the wire rod groove, 3-clamp, 4-side iron, 5-handle, 6-molded shaft. DETAILED DESCRIPTION

[0014] In order to enable those skilled in the art to better understand the solution of the present application, the technical solution in the embodiments of the present application will be clearly and completely described below in conjunction with the drawings in the embodiments of the present application.

[0015] A method for forming a wire rod conductor with an S-bend at the end is specifically completed by the following steps:

[0016] S1. S-bend in the direction of forming elevation: Design and manufacture according to the requirements of the product drawings. Figure 1 The S-bend forming mold shown in the figure wraps the demoulding material and the tightening material around the outer side of the end of the wire that has been straightly gelled, moves the wire so that the center of the wire groove is aligned with the center of the groove on the mold, and then uses a special handle 1 with an axis to bend the coil so that the coil is close to the forming axis 201 at the corresponding corner of the mold, thereby producing the arc required by the drawing, and forming the two arcs of the S-bend in sequence from the center of the coil to the outside.

[0017] S2. The remaining lines on the outside of the S-bend: After the S-bend is formed, replace Figure 2 The end forming die shown in the figure, open all the clamps 3 on the die, remove the side iron 4 on the die, align the center of the groove on the conductor with the center of the groove on the end forming die, and then clamp the straight part of the wire rod with the straight part of the die with the clamp in the straight area, and respectively form the two ends of the wire rod formed in S1, first use the forming handle 5 to bend the straight corner outside the coil S bend at one end of the wire rod to make it rotate along the forming axis 6 to produce a straight corner of the wire rod close to the groove, then manually press the area between the coil straight corner and the lead corner with the die, and then use the same wrench bend method as the straight corner to form the lead corner, so that the forming of one end of the wire rod is completed, and the forming method of the other end is the same;

[0018] S3, glue correction: Considering the springback of metal materials and the error caused by manual operation, the wire after S2 is placed as follows Figure 3 The hot pressing mold shown in the figure has the mold lines of the hot pressing mold cavity processed according to the mold lines and dimensions of the drawing. The deviation existing in the forming process is corrected by using the mold to heat and pressurize the coil during the coil pressing process (the coil is indirectly pressurized by pressurizing the outer side of the mold with a hydraulic press). At the same time, the insulating material clamped in the end of the wire rod before forming is heated. The heating method adopts a method of passing alternating current through the wire rod to generate eddy current in the mold, thereby causing the mold to heat up and heat the insulating material in the wire rod to solidify it.

[0019] In S1, before molding, it is necessary to wrap the mold release material polytetrafluoroethylene film halfway around the outside of the area to be molded to prevent the glue in the insulating material from melting and flowing out when S3 is heated, so that the wire will stick to the mold after solidification and cannot be removed from the mold.

[0020] After the coil area to be formed is wrapped with demoulding material, the outer side needs to be wrapped with a tightening material - a white cloth tape during the forming process to prevent the multi-turn strands from loosening during the forming process.

[0021] When forming the S-bend area in S1, when the formed S-bend is close to the 1 / 4 arc of the center of the wire rod, the forming shaft 201 close to the wire rod groove is used, and the forming shaft 202 on the tool used for forming the S-bend away from the wire rod groove needs to be removed to avoid interference during the forming process. After the first arc is formed, the forming shaft 202 is installed again when forming the second arc to serve as a forming reference.

[0022] When forming the S-bend in S1, the bending forming operation of the coil is completed by a forming handle with a forming restraining rod 101. The handle is connected to the forming shaft through a handle shaft 102 and can rotate around the axis of the forming shaft 201, so that the restraining wire is bent according to the shape line of the forming shaft 201 when the handle is turned.

[0023] The forming binding rod is provided with a bearing 103, which is used to avoid the direct sliding friction between the forming rod binding rod 101 and the tightening material wrapped with the wire rod during the forming process to generate a large resistance, thereby playing a role in reducing the resistance.

[0024] When forming the remaining profiles on the outside of the S-bend in S2, they are formed sequentially from the center of the coil to both ends to avoid forming the profiles at both ends first, which causes the expanded length of the wire reserved in the center to be inconsistent with the actual length, resulting in differences in the final profiles.

[0025] In S2, when forming the remaining profiles on the outside of the S-bend, an L-shaped limiting partition is sandwiched between the forming restraining rod bearing on the forming handle and the wire rod to ensure that the surface of the wire rod is flat after forming.

[0026] During the S3 gelling and correction process, the order of pressurization should be to first apply pressure to the large surface of the coil in the direction of the cross-section perpendicular to the center line, and then to apply pressure to the small surface of the coil, so as to avoid the problem of uneven coil surface; in the direction of the total length of the wire rod, pressurize from the center to both ends in sequence to avoid the situation where the mold is not in the theoretical position and the two ends are pressurized first, resulting in end limitation, and then pressurizing the center area of ​​the coil. The mold reserved in the center area is too long to be expanded, resulting in the inability to pressurize to the theoretical size.

[0027] The present invention is only an exemplary description of the present invention and does not limit its protection scope. Those skilled in the art may also make partial changes thereto, which are within the protection scope of the present invention as long as they do not exceed the spirit of the present invention.

Claims

1. A method for forming a wire rod conductor with an S-bend at the end, characterized in that , including the following steps: S1. Forming an S-bend in the ascending direction: Design and manufacture the corresponding S-bend forming mold according to the requirements of the product drawings, wrap the demoulding material and the tightening material around the outer side of the end of the wire that has been straightly gelled, put the wire into the mold, move the wire so that the center of the wire groove is aligned with the center of the groove on the mold, and then use a special handle with an axis to bend the coil so that the coil is close to the forming axis at the corresponding corner of the mold to produce the arc required by the drawing, and form two arcs of the S-bend from the center of the coil to the outside in sequence; S2. Form the remaining profiles on the outside of the S-bend: After the S-bend is formed, replace the end forming die, align the center of the groove on the conductor with the center of the groove on the die, and clamp the straight part of the wire rod with the straight part of the die with a clamp. Form the two ends of the wire rod formed in S1 separately. First, use a forming handle to bend the straight corner on the outside of the S-bend of the coil at one end of the wire rod to rotate it along the forming axis to create a straight corner of the wire rod close to the groove. Then, manually press the area between the straight corner of the coil and the lead corner with the die. Then, use the same wrench-bending method as the straight corner to form the lead corner. At this point, the forming of one end of the wire rod is completed, and the forming method of the other end is the same. S3, Gelatinization correction: Correct the deviation in the forming process, and heat the insulating material clamped in the end of the wire rod before forming. The heating method is to pass alternating current through the wire rod to generate eddy current in the mold, thereby causing the mold to heat up and heat the insulating material in the wire rod to solidify it.

2. A method for forming a wire rod conductor with an S-bend at the end according to claim 1, characterized in that: Said S1, before molding, wraps the outer side of the area to be molded with a polytetrafluoroethylene film of demoulding material.

3. A method for forming a wire rod conductor with an S-bend at the end according to claim 2, characterized in that: In the above S1, after the demoulding material is wrapped with the polytetrafluoroethylene film, the outer side of the demoulding material also needs to be wrapped with the white cloth tape used as the tightening material in the molding process.

4. A method for forming a wire rod conductor with an S-bend at the end according to claim 1, characterized in that: When forming the S-bend area in S1, when the formed S-bend is close to the 1 / 4 arc of the center of the wire rod, the forming shaft on the tool used to form the S-bend away from the wire rod groove needs to be removed. After the first arc is formed, the forming shaft is installed again when forming the second arc to serve as a forming reference.

5. The method for forming a wire rod conductor with an S-bend at the end according to claim 1, characterized in that: In S1, when forming the S-bend, the bending forming operation of the coil is completed by a forming handle with a forming restraining rod, and the forming handle is connected to the forming shaft by an axle pin and rotates around the forming shaft.

6. A method for forming a wire rod conductor with an S-bend at the end according to claim 5, characterized in that: In S1, a bearing is mounted on the molded restraining rod.

7. A method for forming a wire rod conductor with an S-bend at the end according to claim 1, characterized in that: In the above-mentioned S2, when forming the remaining profile lines outside the S-bend, they are formed sequentially from the center of the coil to both ends.

8. The method for forming a wire rod conductor with an S-bend at the end according to claim 1, characterized in that: In S2, when forming the remaining profiles on the outer side of the S-bend, an L-shaped limiting partition is sandwiched between the forming binding rod bearing on the forming handle and the wire rod.

9. A method for forming a wire rod conductor with an S-bend at the end according to claim 1, characterized in that: In S3, the order of pressurization during the gelation correction process is to first apply pressure to the large surface of the coil and then to the small surface of the coil in the direction of the cross section perpendicular to the center line; and to apply pressure from the center to both ends in the direction of the total length of the wire rod.

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