High magnetic yoke jaw pole blank forging new process

Abstract

The present application relates to high magnetic yoke jaw pole blank forging technical field, and disclose high magnetic yoke jaw pole blank forging new process, S1, blank preheating;S2, upsetting preforming press, the preforming die is used to the blank after heating preforming press processing;S3, upsetting finish forging press, the finish forging die is used to preforming blank finish forging press processing;S4, red cutting edge, in preforming process through conventional crank press on the columnar blank is formed by preliminary forging preforming blank, after finish forging process, the preforming blank is forged into finish forging blank gradually by using large tonnage friction press, the overall forming stretch of blank is reduced, with smaller machining allowance, can reduce the consumption of materials, realizes the process optimization, reduces the use of large tonnage press in the process of forging, reduces the process equipment requirement and purchase cost, and can save the operation of equipment labor consumption, further reduces the processing cost of workpiece.

Description

Technical Field

[0001] This invention relates to the field of high magnetic yoke claw pole blank forging technology, specifically a new forging process for high magnetic yoke claw pole blanks. Background Technology

[0002] The high magnetic yoke claw pole is a core component in the rotor assembly of an alternator. Its main function is to convert the axial magnetic field generated by the excitation coil in the rotor into a radial magnetic field, so that the rotor can obtain an alternating magnetic field distributed in three dimensions in space when it rotates. This alternating magnetic field generates an alternating current relative to the stator. The high magnetic yoke claw pole is an important component of the magnetic pole of an automotive alternator. It is generally made of ferromagnetic material. Due to its special shape, it is currently commonly made of cast steel and needs to be processed by forging.

[0003] To reduce processing steps, traditional high-magnetic-yoke claw pole blank forging processes often employ large-stroke forging. For example, in an existing high-magnetic-yoke claw pole blank forging process, the forging process includes two steps: pre-forging and precision forging. Due to the need for large-stroke forging and stretching, a 1600-ton friction press is used in the pre-forging and a 1000-ton friction press in the precision forging. Because the single stretching stroke is large, the stress on the blank is relatively high. As the stroke increases, the amount of blank required also increases. Since the volume of the finished product is fixed, a lot of scrap needs to be removed during the trimming process, resulting in material waste. Furthermore, the stretching process requires the participation of large-tonnage presses, which places high demands on the processing equipment, increases the purchase cost of the equipment, and is not conducive to reducing production costs. Summary of the Invention

[0004] The purpose of this invention is to provide a new forging process for high magnetic yoke claw pole blanks to solve the problems mentioned in the background art.

[0005] To achieve the above objectives, the present invention provides the following technical solution: a new process for forging high magnetic yoke claw pole blanks, comprising the following steps:

[0006] S1. Preheating of the blank: The blank is heated to a specific temperature using an intermediate frequency furnace.

[0007] S2. Upsetting blank pre-forging: The heated blank is pre-forged using a pre-forging die. The heated blank is placed into the pre-forging die, and the forging pressure is provided by a crank press to pre-forge the blank to form a pre-forged blank.

[0008] S3. Upsetting blank precision forging: Precision forging of pre-forged blank using precision forging die. The pre-forged blank is placed into the precision forging die, and the forging pressure is provided by the friction press to perform precision forging of the pre-forged blank to form a precision forged blank.

[0009] S4. Red edge trimming: The precision forging blank is placed in the trimming die, and the trimming driving force is provided by the crank press to trim the precision forging blank.

[0010] Preferably, in S1, the blank is a cylindrical blank, and the preheating temperature of the blank is 975℃-1025℃.

[0011] Preferably, in S2, the pre-forging die includes an upper pre-forging die and a lower pre-forging die, the lower pre-forging die being fixed on the upper part of the horizontal platform, and the upper pre-forging die being installed on the drive end of the crank press.

[0012] Preferably, the top side of the pre-forging lower die is provided with a protruding pre-forging forming groove. The preheated blank is placed between the pre-forging upper die and the pre-forging lower die. The lower part of the blank is fitted with the protruding precision forging forming groove. The pre-forging upper die is driven by a crank press to forge and form the blank. The pressure provided by the crank press is 195-200 tons.

[0013] Preferably, in S2, the upper part of the pre-forged blank is provided with an upsetting head seat, and the lower part of the pre-forged blank is provided with an upsetting protrusion.

[0014] Preferably, in S3, the temperature of the pre-forged blank is maintained at 150℃-155℃ during forging. The precision forging die includes a precision forging upper die and a precision forging lower die. The precision forging lower die is fixed on the upper part of the horizontal platform, and the precision forging upper die is installed on the drive end of the friction press.

[0015] Preferably, the upper forging die has a headstock forming groove at the bottom center, the lower forging die has a protruding forging forming groove at the top center, the protruding forging forming groove has a headstock forming groove at the top opening side, and the lower headstock forming groove has vertical claw forming grooves evenly distributed at the bottom periphery.

[0016] Preferably, the pre-forged blank is placed between the upper and lower precision forging dies, and the upsetting protrusion at the bottom of the pre-forged blank is fitted into the inner side of the forming groove on the headstock.

[0017] Preferably, the upper part of the forged blank is provided with a magnetic yoke head seat, the magnetic yoke head seat is uniformly provided with magnetic yoke vertical claws on its circumferential side, a circular central hole is provided at the top center of the magnetic yoke head seat, and a magnetic yoke protrusion is provided at the lower part of the magnetic yoke head seat. The upper forging die performs secondary forging of the pre-forged blank under the drive of a friction press. The pressure provided by the friction press is 1600-1605 tons. During forging, the runout of the upper and lower forging dies is ≤0.4, and the misalignment of the magnetic yoke vertical claws is ≤0.3.

[0018] Preferably, in S4, the crank press provides a pressure of 155-160 tons to the trimming die.

[0019] Compared with the prior art, the present invention, employing the above technical solution, has the following technical effects:

[0020] 1. This invention adopts a segmented forging forming process, which involves forging the blank in stages. In the pre-forging process, a conventional crank press is used to pre-forge the cylindrical blank into an upsetting pre-forged blank. Then, in the precision forging process, a high-tonnage friction press is used to forge the pre-forged blank into a precision forged blank, which is gradually forged and stretched to form the blank. This avoids excessive stretching of the blank and reduces the overall forming stretch of the blank. The blank usage is smaller, and there is a smaller machining allowance, which can reduce material consumption.

[0021] 2. Process optimization has been achieved. Only the precision forging process of the blank is used with a large-tonnage friction press. The rest of the processing can be completed by conventional punch press. The use of large-tonnage presses is reduced in the forging process, which reduces the requirements and purchase costs of the processing equipment and saves the processing cost of the workpiece.

[0022] 3. Large-tonnage presses require multiple operators. However, the reduced equipment requirements save on manual labor costs, reduce manpower consumption in the processing flow, save on labor costs, and further reduce the processing cost of the workpiece. Attached Figure Description

[0023] To more clearly illustrate the technical solutions in the embodiments of this application or the prior art, the drawings used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments of this application. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0024] Figure 1 This is a schematic diagram of the upper structure of the pre-forging die of the present invention;

[0025] Figure 2 This is a schematic diagram of the lower structure of the pre-forging die of the present invention;

[0026] Figure 3 This is a schematic diagram of the cross-sectional structure of the pre-forging die of the present invention;

[0027] Figure 4 This is a schematic diagram of the three-dimensional structure of the pre-forged blank of the present invention;

[0028] Figure 5 This is a schematic diagram of the upper structure of the precision forging die of the present invention;

[0029] Figure 6 This is a schematic diagram of the lower structure of the precision forging die of the present invention;

[0030] Figure 7This is a schematic diagram of the cross-sectional structure of the precision forging die of the present invention.

[0031] Figure 8 This is a schematic diagram of the precision forging blank structure of the present invention;

[0032] Figure 9 This is a schematic diagram of the forging curve of the present invention;

[0033] Figure 10 This is a schematic diagram of the stress distribution of the present invention.

[0034] Explanation of reference numerals in the attached drawings: 11. Upper pre-forging die; 12. Lower pre-forging die; 121. Pre-forging forming groove for protruding post; 13. Pre-forging blank; 131. Upsetting head seat; 132. Upsetting protruding post; 21. Upper precision forging die; 211. Upper forming groove on the head seat; 22. Lower precision forging die; 221. Precision forging forming groove for protruding post; 222. Vertical claw forming groove; 223. Lower forming groove on the head seat; 23. Precision forging blank; 231. Magnetic yoke head seat; 232. Circular central hole; 233. Vertical claw of magnetic yoke; 234. Magnetic yoke protruding post. Detailed Implementation

[0035] The technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0036] It should be noted that the structures, proportions, sizes, etc., shown in the accompanying drawings of this specification are only for the purpose of assisting those skilled in the art in understanding and reading the content disclosed in the specification, and are not intended to limit the conditions under which this application can be implemented. Therefore, they have no substantial technical significance. Any modifications to the structure, changes in the proportions, or adjustments to the size should still fall within the scope of the technical content disclosed in this application, provided that they do not affect the effects and purposes that this application can produce.

[0037] Example

[0038] Please see Figure 1-10 This invention provides a technical solution: a new process for forging high magnetic yoke claw pole blanks, comprising the following steps:

[0039] S1. Preheating of the blank: A blank of a specific length is cut. The blank is a cylindrical blank. Before forging, the blank is heated in an induction furnace. The blank is placed inside the induction furnace and heated to a specific temperature. The induction furnace is used to heat the blank to 1000℃, so that the blank has good plasticity.

[0040] S2. Upsetting pre-forging: The heated blank is pre-forged using a pre-forging die. The pre-forging die includes an upper pre-forging die 11 and a lower pre-forging die 12. The lower pre-forging die 12 is fixed on the upper part of the horizontal platform as a fixed die, and the upper pre-forging die 11 is installed on the drive end of the crank press as a lower pressing die. To facilitate the installation and positioning of the blank and the forging of the blank, a protruding pre-forging forming groove 121 is provided in the middle of the top side of the lower pre-forging die 12, as shown in the attached figure. Figure 3 As shown, the pre-forging forming groove 121 of the protruding column is a tapered cylindrical groove, wider at the top and narrower at the bottom, which facilitates the forging and forming of the blank. The preheated blank is placed between the upper pre-forging die 11 and the lower pre-forging die 12. The lower part of the blank is fitted with the upper part of the precision forging forming groove 221 of the protruding column, realizing the installation and positioning of the blank. Then, the upper pre-forging die 11 forges and forms the blank under the drive of the crank press. The crank press provides a pressure of 200 tons. The upper pre-forging die 11 and the lower pre-forging die 12 are closed by the forging pressure provided by the crank press. The pre-forging die 11 and the lower pre-forging die 12 are used to pre-forge the blank to form the pre-forged blank 13, as shown in the attached figure. Figure 4 As shown, under the pressure of the upper pre-forging die 11, the upper part of the pre-forging blank 13 forms an upsetting head seat 131, and under the action of the upper protrusion pre-forging forming groove 121 of the lower pre-forging die 12, an upsetting protrusion 132 is formed on the lower part of the pre-forging blank 13, thus completing the pre-forging process of the blank.

[0041] S3. Precision forging of the pre-forged blank: The pre-forged blank 13 is precision forged using a precision forging die. The pre-forged blank 13 is removed from the pre-forging die and placed back into the medium-frequency furnace. During forging, the temperature of the pre-forged blank 13 is maintained at 150℃. The pre-forged blank 13 is then placed into the precision forging die, which includes an upper precision forging die 21 and a lower precision forging die 22. The lower precision forging die 22 is fixed to the upper part of the horizontal platform as a fixing die. To facilitate the installation and positioning of the pre-forged blank 13, the lower precision forging die 22... A protruding column precision forging groove 221 is provided in the middle of the top side of the pre-forged blank 13. The pre-forged blank 13 is placed between the upper precision forging die 21 and the lower precision forging die 22. The upsetting protruding column 132 at the bottom of the pre-forged blank 13 is fitted into the inner side of the forming groove 211 on the head seat to realize the fitting and positioning of the pre-forged blank 13. In order to facilitate the forging and forming of the pre-forged blank 13, a lower forming groove 223 on the top opening side of the protruding column precision forging groove 221 is provided. Vertical claw forming grooves 222 are evenly provided on the bottom of the periphery of the lower forming groove 223.

[0042] The upper forging die 21 is installed at the drive end of the friction press as a lower pressing die. To facilitate the forging of the pre-forged blank 13, a forming groove 211 on the headstock is provided in the middle of the bottom side of the upper forging die 21. The friction press provides forging pressure to perform precision forging of the pre-forged blank 13 to form the precision forged blank 23. The pressure provided by the friction press is 1600 tons. During forging, the runout of the upper forging die 21 and the lower forging die 22 is ≤0.4, and the misalignment of the magnetic yoke vertical claw 233 is ≤0.3. (See attached diagram) Figure 8 As shown, the upper part of the formed precision forged blank 23 is provided with a magnetic yoke head seat 231, the magnetic yoke head seat 231 is uniformly provided with magnetic yoke vertical claws 233 on the circumferential side, a circular central hole 232 is provided at the top center of the magnetic yoke head seat 231, and a magnetic yoke protrusion 234 is provided at the lower part of the magnetic yoke head seat 231.

[0043] S4. Red-edge trimming: The precision forging blank 23 is placed in the trimming die. A crank press provides the trimming driving force, with a pressure of 160 tons applied to the trimming die. This trims the excess material on the sides of the precision forging blank 23, completing the workpiece processing. The blank is forged in stages. In the pre-forging process, a conventional crank press is used to initially forge the cylindrical blank into a upset pre-forging blank 13. Then, in the precision forging process, a high-tonnage friction press is used to forge the pre-forging blank 13 into the precision forging blank 23, gradually forging and stretching it as shown in the attached diagram. Figure 9 and attached Figure 10 As shown, the stretching stroke is reduced, the precision forging force of the new process is 407 tons, and the maximum stress point of the blank is 397 MPa at the column mouth of the magnetic yoke. This avoids excessive stretching of the blank, reduces the amount of blank used, has a smaller machining allowance, and reduces material consumption.

[0044] In summary, this invention employs a segmented forging process, where the blank is forged in stages. In the pre-forging process, a conventional crank press is used to initially forge the cylindrical blank into a upset pre-forged blank 13. Then, in the precision forging process, a high-tonnage friction press is used to forge the pre-forged blank 13 into a precision forged blank 23 through gradual forging and stretching. This avoids excessive stretching of the blank and reduces the overall stretching amount, resulting in less blank material consumption and a smaller machining allowance. Furthermore, it optimizes the process, using a high-tonnage friction press only in the precision forging process, while the remaining processes can be completed using conventional punch presses. This reduces the use of high-tonnage presses during forging, lowering the requirements and purchase costs of processing equipment, saving on workpiece processing costs. Moreover, the reduced equipment requirements save on manual operation, further reducing labor costs and ultimately lowering workpiece processing costs.

[0045] The embodiments of the present invention have been described in detail above with reference to the accompanying drawings. It should be noted that implementations not illustrated or described in the drawings or the main text of the specification are forms known to those skilled in the art and are not described in detail. Furthermore, the definitions of the components described above are not limited to the various specific structures, shapes, or methods mentioned in the embodiments, and those skilled in the art can easily modify or substitute them.

[0046] The specific embodiments described above further illustrate the purpose, technical solution, and beneficial effects of the present invention. It should be understood that the above descriptions are merely specific embodiments of the present invention and are not intended to limit the present invention. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of the present invention should be included within the protection scope of the present invention.

Claims

1. A new forging process for high magnetic yoke claw pole blanks, characterized in that, Includes the following steps: S1. Preheating of blank: The cylindrical blank is heated to 975℃-1025℃ using an intermediate frequency furnace; S2. Upsetting pre-forging: The heated cylindrical blank is pre-forged using a pre-forging die. The heated cylindrical blank is placed into the pre-forging die, and a forging pressure of 195-200 tons is provided by a crank press to pre-forge the cylindrical blank to form a pre-forged blank (13). The upper part of the pre-forged blank (13) is provided with an upsetting head seat (131), and the lower part of the pre-forged blank (13) is provided with an upsetting protrusion (132). S3. Precision forging of the pre-forged blank (13): The pre-forged blank (13) is precision forged using a precision forging die. The pre-forged blank (13) is placed into the precision forging die, and a forging pressure of 1600-1605 tons is provided by a friction press to precision forge the pre-forged blank (13) to form a precision forged blank (23). The precision forging die includes a precision forging upper die (21) and a precision forging lower die (22). The bottom side of the precision forging upper die (21) is provided with a headstock forming groove (211), and the top side of the precision forging lower die (22) is provided with a protruding column precision forging forming groove (221). The top opening side of the precision forging groove (221) of the protruding column is provided with a head seat lower forming groove (223), and the bottom of the lower forming groove (223) of the head seat is uniformly provided with vertical claw forming grooves (222). The upper part of the precision forging blank (23) is provided with a magnetic yoke head seat (231), and the circumferential side of the magnetic yoke head seat (231) is uniformly provided with magnetic yoke vertical claws (233). The center of the top side of the magnetic yoke head seat (231) is provided with a circular central hole (232), and the lower part of the magnetic yoke head seat (231) is provided with a magnetic yoke protruding column (234). S4. Red edge trimming: Place the precision forging blank (23) into the edge trimming die, and use a crank press to provide a trimming driving force of 155-160 tons to trim the precision forging blank (23).

2. The new forging process for high magnetic yoke claw pole blanks according to claim 1, characterized in that: In S2, the pre-forging die includes an upper pre-forging die (11) and a lower pre-forging die (12). The lower pre-forging die (12) is fixed on the upper part of the horizontal platform, and the upper pre-forging die (11) is installed on the drive end of the crank press.

3. The new forging process for high magnetic yoke claw pole blanks according to claim 2, characterized in that: The top side of the pre-forging lower die (12) is provided with a protruding pre-forging forming groove (121). The preheated blank is placed between the pre-forging upper die (11) and the pre-forging lower die (12). The protruding pre-forging forming groove (121) is a conical columnar groove. The pre-forging upper die (11) forges the columnar blank under the drive of the crank press.

4. The new forging process for high magnetic yoke claw pole blanks according to claim 3, characterized in that: In S3, the lower forging die (22) is fixed on the upper part of the horizontal platform, and the upper forging die (21) is installed on the drive end of the friction press.

5. The new forging process for high magnetic yoke claw pole blanks according to claim 4, characterized in that: In S3, the pre-forged blank (13) is placed between the upper forging die (21) and the lower forging die (22), and the upsetting protrusion (132) at the bottom of the pre-forged blank (13) is fitted into the inner side of the protrusion forging groove (221).

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