JPS637152A - Manufacture of pole piece - Google Patents

Abstract

PURPOSE:To rapidly and accurately form a pole piece for a long period by lubricating it after a blanking step for forming a blank, then continuously executing a bending step, a forming step, a piercing step and an ironing step. CONSTITUTION:A pole piece manufacturing apparatus consists of a pressing machine l for executing a blanking step, and a transfer pressing machine 2. A lubricating unit 9 for executing lubricating step is provided between the machines 1 and 3. The machine 2 has a first metal mold 3 for executing bending step, a second metal mold 4 for executing a forming step, a third metal mold 5 for executing a piercing step, and a fourth metal mold 6 for executing an ironing step arranged in this order, and feeding means 7 and inverting means 8 for feeding a blank 100 are provided.

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to a method of manufacturing a pole piece of a claw-shaped rotor used in an alternating current generator or the like.

[Background technology and its problems]

In dielectric alternating current optical TJs, machines, etc. for automobiles, those having a structure using the iron core of a claw-shaped rotor, so-called pole pieces, are widely used.

This pole piece generally has a fuselage inner surface 11 and a fuselage outer surface 12 with high flatness and parallelism as shown in FIGS. 8 and 9.
A body 10 having a body 10 is provided with a plurality of (six in FIG. 8) claw parts 20 integrally formed therein, and a center hole in the center of the body 10 for inserting a rotating shaft or for mounting a joint. 16 are configured. Also, pole piece 4
The body 10 of 00 has a coil mounting bobbin (not shown) for positioning it. Ji18.18 is provided. Note that 21 and 22 are the inner and outer surfaces of the claw portion 20, 23 and 23 are the side surfaces of the claw, and 24 are the upper surface of the claw tip portion 25. Further, 14 is a body 10 on the proximal end side of the claw portion 20.
This is the part of the song.

In view of its purpose and function, such a pole piece 400 has a high hole diameter of the center hole 16, perpendicularity and flatness of the inner and outer surfaces 11 and 12 of the body with respect to the center hole 16, as well as the inner and outer diameter dimensions of the claw portion 20. Dimensional accuracy is required. In particular, since the pole piece 400 is installed as a rotating body in an automobile or the like, the claw portion 2 is designed to facilitate centering and assembly, to facilitate adjustment, and to eliminate rotational eccentricity and causes of vibration.
The inner and outer diameters of 0 and the center hole 16 must be highly accurate and have a circular diameter.

Therefore, in the past, iron ingots were formed by hot forging or cold forging, or by plastic working by bending and cold forming. However, in the case of hot forging, many mechanical cutting processes must be added, which not only requires a large burden of time and labor, but also has the problem of occurrence of cracks due to the mechanical cutting. In particular, the center hole 1 is adjusted to the inner and outer diameters of the claw portion 20 and the reciprocal circle while ensuring the accuracy of the predetermined hole diameter.
Due to the shape of the pole piece 400, machining the pole piece 6 required a large number of man-hours.

In addition, 1. Cold forging from an iron ingot requires a large number of steps, requires a large press, and increases equipment costs.

Next, although bending and cold forming have the advantage of not requiring mechanical cutting, the intermediate product must be annealed and lubricated at various points between the bending process and the cold-open forming process, making these interventions difficult. This has disadvantages in that it is uneconomical and difficult to automate because it reduces production efficiency and requires the installation of a press machine or the like for each process. In addition, if these are omitted, the press machine etc. will become large because the material must be formed all at once from work-hardened material by bending, the life of the mold will be short and it cannot be used for a long time, and depressions will remain in the claws etc. It had many drawbacks such as poor product accuracy. Furthermore, it is extremely difficult to achieve a predetermined precision in the reciprocity of the center hole 16 and the claw portion during the air forming process, etc. due to problems with the degree of processing.

[Purpose of the invention]

An object of the present invention is to provide a method for manufacturing a pole piece that is advantageous in equipment economy and allows rapid and highly accurate processing over a long period of time.

[Means and effects for solving the problems] The present invention has the following features:
In order to eliminate the above conventional problems, we focused on the unique shape of the pole piece and applied lubrication treatment after the blanking process to form the material (blank), and then performed the bending process, forming process, piercing process, and ioning process. This is done continuously. For this reason, a blanking process in which a material of a predetermined shape is punched out from raw materials,
A lubrication treatment step in which a lubricant is applied to the material, a bending step in which the material after the lubrication treatment is bent to preform the body and the claw portion, and the dimensions of the preformed claw portion are formed into predetermined dimensions. The forming process, the piercing process in which the center hole is machined to the specified size based on the diameter of the claw part formed to the specified size, the ironing process on the outer surface of the claw, and the sizing process to obtain flatness of the inner and outer surfaces of the body. and an ioning step in which processing is performed within the same stroke, and the bending step, forming step, piercing step, and ioning step are continuously processed to achieve the above object.

In the method for manufacturing a pole piece configured in this way, first, a blanking process is performed to punch out a material with a certain shape that takes into consideration the shape of the pole piece (final product) and the subsequent processing method.
The material is thoroughly lubricated. Next, there is a bending process in which the lubricated material is preformed by bending the body and the claw part, a forming process in which the preformed claw part is finished to a predetermined size, and a center hole is formed based on the diameter of the claw part. The piercing process for finishing the nail, and the ioning process for ironing the outer surface of the nail and sizing process for obtaining parallelism and flatness of the inner and outer surfaces of the body within the same stroke are performed continuously in this order.

Therefore, if lubrication treatment is performed after the blanking process, there is no need to perform lubrication treatment between subsequent processes, so it is only necessary to install two press machines, one for the blanking process and one for the subsequent bending process, etc. (Simple equipment,
It is economically advantageous and it is easy to make your own VJ. In addition, after the bending process, multi-stage plastic processing is performed that is optimal for the unique shape of the pole piece, so there is no need to perform extrusion processing with excessive force, and the stress concentration on the mold is reduced, so the mold etc. can be lengthened. Can be used stably for a period of time. Furthermore, by performing a piercing process at a suitable location, the center hole is finished to have the same inner and outer diameters as the claw portion and a predetermined dimension. In this way, highly accurate pole pieces can be manufactured with good production efficiency.

〔Example〕

A method for manufacturing a pole piece according to the present invention will be explained in detail with reference to the drawings.

The manufacturing method of this embodiment is carried out by the pole piece manufacturing apparatus shown in FIG. 1, which is composed of a press machine 1 for carrying out a blanking process and a so-called transfer press machine 2. Between the two press machines 1 and 3 is a lubrication treatment device 9 that carries out the lubrication treatment process.
is provided. And transfer press machine 2
is a first mold 3 for carrying out the bending process;
A second mold 4 for performing a forming process, a third mold 5 for performing a piercing process, and a fourth mold 6 for performing an ionizing process are arranged in this order, and the material 20 is
0, etc., and a reversing means 8. Here, the flow of the material 200, etc. is indicated by arrows A, B, and C in FIG.

It is assumed that the materials are transferred in the order of D, and the material 200 is the raw material 1.
An intermediate form formed from 00 until it is finished into the final product, the pole piece 400 shown in FIGS. 8 and 9, will be referred to as an intermediate product 300. In addition, supply means other than the above-mentioned transfer means 7.7,
Conveyance/transfer means, take-out means, etc. are not shown.

Pole piece 4 carried out in such a manufacturing device
The manufacturing method of 00 will be explained below for each step.

(Blanking process) A flat plate-shaped raw material 100 is supplied to the press machine 1 from the direction of the arrow shown in FIG. Here, the press machine 1 has a shape that satisfies the dimensions of the pole piece 400 (Fig. 6 (
A)) The raw material 100 is continuously punched out to form the raw material 200.

In this embodiment, in this process, the pilot hole 1 of the center hole 16 is
5 is to be molded. In this way, the blanking process is performed. Material 200 is pole piece 4
When commercialized as 00, the force claw part 20 in which the pilot hole 15 of the center hole 16 for inserting a rotating shaft or mounting a joint is provided still remains in the same flat plate shape as the body 10. Note that the prepared hole 15 is used as a guide hole in the subsequent bending process.

(Lubrication Treatment Step) The material 200 is conveyed in the direction of arrow B shown in the first recess and returned in the direction of C. Here, the lubrication treatment process is carried out by the lubrication treatment device 9.
It will be carried out in This example includes degreasing, water washing, pickling, etc. before and after neutralization treatment, etc., and is soaked in Bonderite (trade name) aqueous solution to form a solid that retains the lubricant on the entire surface of the material 200. This is a lubrication treatment in which a lubricant is attached to the lubrication-retaining layer by proactively forming a lubrication-retaining layer, such as a zinc phosphate film, which is a typical example because it is easy to process and has a small coefficient of friction. It is said that

(Bending process) In this bending process, the material 200 is transferred to the transfer press I! It is set in the first mold 3 of the machine 2 and subjected to bending and ironing in one stroke to preform a plurality of claw parts 20, 20, . . . that stand up from the body 10. The first mold 3 includes a die 30° anvil 31. which forms the lower mold as shown in FIG. counter punch 3
4. Consists of a punch 32 forming an upper mold and a round shaft-shaped mandrel 33 for inserting into the pilot hole 15 to position the material 200. Therefore, in this bending process, the inner and outer diameters formed by the inner claw surface 21 and the outer claw surface 22 are regulated by the outer diameter of the punch 32 and the inner diameter of the die 30. This is a struggle to press and form an intermediate product 300 having the shape shown in FIG. 6(B).

In this way, in the bending process, each nail side 2
3.23. As is clear from the shapes of the punch 32 and die 30 shown in FIG. 2, the upper surface 24 of the claw and the curved portion 14 are bent and ironed in a free state. Intermediate product from O thickness 11n1 300
The pushing force of the punch 32 can be made relatively small even if the wall thickness of the claw tip 24 is 3.4 mm, making it possible to downsize the press machine and extend the life of the first mold 30. .

Here, the features of the present invention will be confirmed.

In the above-mentioned bending process, since the amount of straining is large, the work hardening of the claw portions 20 is particularly severe.

Therefore, it can be seen that it is sufficient to anneal the preformed intermediate product 300. However, with annealing, the material
It becomes impossible to continuously perform plastic working from zero to the final product, pole piece 400, which significantly reduces productivity. If further annealing is performed, the intermediate product 300 must be subjected to a re-lubrication process similar to the lubrication process performed after the blanking process. This not only further reduces the productivity but also increases the time and economic burden of the relubrication process, and requires additional means of transport to the relubrication process. This leads to a situation where a separate press machine must be added to the previous press machine, and the disadvantage and inconvenience cannot be resolved.

Therefore, it is conceivable to provide one forming process in which the intermediate product 300 after the bending process is finished into the pole piece 400 at once without annealing and relubrication treatment. However, if such a manufacturing method is used, the press machine for carrying out this forming process will require an extremely large pushing force and driving force due to the unique shape of the pole piece 400, so it is necessary to avoid increasing the size of the equipment. Moreover, the mold etc. will fail in an extremely short period of time. Furthermore, the claw part 2
Recesses occur on each of the outer surfaces 22 and 22 of 0, and predetermined dimensional accuracy cannot be established. Therefore, the problem remains that mechanical cutting still has to be performed in the end, resulting in high costs.

Here, the present invention analyzes the interrelationship between the unique form of the pole piece 400, production efficiency, and product accuracy, and as a result of many tests and studies, the bending process is followed by a forming process, a piercing process, and an ionizing process. Moreover, it is characterized in that these steps can be performed continuously.

Note that further subdividing the forming process, piercing process, and forming process into four or more processes not only complicates the selection of each mold specification, but also makes the equipment as a whole uneconomical.

(Forming process) The forming process consists of each claw side surface 23, 23, the claw top surface 24, and the curved part 14, which have been made free in the bending process.
Shaping of the claw portion 2o to bring the shape closer to a predetermined dimension, shaping of the body 1o to increase parallelism and flatness between the inner surface 11 and the outer surface 12 of the body, and forming grooves 1B, 1 in the body 1o for positioning the bobbin.
This is the step of providing B. The desired intermediate product 300 is shown in Figure 6 (
As shown in C). This forming step is then performed in a second mold 4 (see FIG. 3). Intermediate product 3
00 is transferred from the first mold 3 by the transfer means 7, 7, and its posture is reversed by the reversing means 8 so that the claw portion 20 faces downward in the figure.

Here, the forming process of the forming process will be explained with reference to FIG. There is a large gap S at a location corresponding to the claw side surface 23, 23 and the claw inner surface 21. intermediate state (
In B), the claw tips 2 and 5 are in contact with the die 40, but the inner surface 11 of the body 10 is not yet in contact with the upper end surface of the counter punch 44, leaving a gap C. therefore,
In the final state of (C), even if the flatness of the inner and outer surfaces 11°12 of the fuselage is increased and the curvature of the curved portion 14 is made smaller, the gap between the die 40 and the claw portion 20 that occurs in the intermediate state g (B) and the claw The recess Q generated on the outer surface 22 of the claw of the portion 20 remains. In particular, the cross-sectional view CD shown along arrow line D-D in FIG. 4(A)
) When the claw portion 20 has a chamfered portion 28, as shown in (E), which is a cross section equivalent to that shown in FIG.

In this way, in the forming step in the present invention,
Recognizing work hardening in the bending process, downsizing equipment, increasing flexibility in selecting various dimensions of equipment components, intermediate products 3
In order to avoid stress concentration on the 00 molding die 4 and reduce the pushing force, the above-mentioned gaps are allowed to remain.

(Piercing process) The piercing process is carried out using the third mold 5, and is to form a center hole 16 with a predetermined size, which has a larger diameter than the diameter of the pilot hole 15 formed in the previous blanking process. Therefore, since the pilot hole 15 has already been provided, a kind of escape section can be used, so that the center hole 16 can be formed with high accuracy with a relatively small force.

The third mold 5 is not shown because it has almost the same structure as the second mold 4 except that the outer diameter of the punch is equal to the inner diameter of the center hole 16 (no mandrel is required).

Therefore, the intermediate product 30 formed in the forming process
The center hole 16 is completed with high accuracy and removability based on the inner and outer diameter dimensions of the claw portion 20 of No. 0.

This eliminates the need for mechanical cutting later. Note that the intermediate product 300 after processing in this step is the same as that shown in FIG. 6(C) except for the dimensional accuracy of the center hole 16.

(Ioning process) The forming process is to obtain the final product, ie, the pole piece 400, from the intermediate product 300. The intermediate product 300 transferred from the third mold 5 by the transfer means 7.7 is transferred to the fourth mold 6. Finish molding is performed on the inner and outer surfaces 11 and 12 of the fuselage 10.
The parallelism and flatness of the nails are further improved, and the outer surface of the claw
This eliminates deterioration in the shape of the claw portion 20 due to work hardening that remains due to the ironing process in step 2 and no subsequent annealing, and completes the overall dimensional accuracy to a predetermined level.

Therefore, as shown in FIG. 5(A), the fourth mold 6 has an inner diameter smaller than the outer diameter of the claw portion 20 of the intermediate product 300 formed in the preceding forming process and piercing process. The straight land portion L (β=
Approach angle α (12 to 18 @
) and its intermediate product 300
The counter punch 64 has a round shape with the same inner diameter and the same taper angle as the inner diameter of the claw part 20, and the upper end surface 65 is flat. It is composed of a mandrel 63 etc. with a diameter. Therefore, the intermediate product 300 is set on the die 60 (see FIG. 5(A)), and the punch 62 is
to size the fuselage 10 by pushing it into the die 60 (same as (
See B).

At this time, the flatness of the upper and lower surfaces 11 and 12 of the intermediate product 300 and the dimensional accuracy of the center hole 16 are significantly improved. Thereafter, the outer diameter of the claw portion can be ironed using the inner diameter Dr of the die 50 while being non-knocked out using the counter punch 64. In this case, since the stress state is such that the outer surface 22 of the claw is released and pulled out, the shape such as the degree of taper of the outer surface 22 of the claw is improved to a predetermined accuracy without changing the outer diameter of the claw portion 20. , it is possible to finish the pole piece 400 (see FIG. 6(D)) with predetermined dimensions.

Therefore, according to this embodiment, the blanking process is carried out by the press machine 1, and the bending process to the ionizing process are carried out by the transfer press 2, so unlike the conventional method, a press machine etc. must be provided for each process. The disadvantages are eliminated and the equipment can be made smaller and more economical. Further, since the bending process and the like after the lubricant treatment process can be performed continuously, automation as a whole can be achieved.

In addition, since the bending process is divided into a forming process, a piercing process, and an ironing process, the pushing force of each mold 4, 5, 6 does not have to be excessive. In addition, since the degree of processing is adapted to the unique shape, precision, etc. of the pole piece 400, it is possible to produce products with high precision and predetermined dimensions. Furthermore, even if work hardening occurs during the bending process, buckling phenomena caused by this can be avoided, and the claw portion 20
Since the unevenness remaining on the outer periphery can be effectively removed, high-precision machining is guaranteed from this point as well.

In addition, the degree of processing of the bending process, forming process, piercing process, and ioning process is determined based on the dimensions of the material 200 and the pole piece 400, their accuracy, etc. Compared to the equipment specifications (dimensions of various parts, pushing force, etc.) for molds and the like used to carry out one forming process were strict, the equipment can have a large degree of leeway. In addition, it has the excellent effect that it is not necessary to perform annealing or relubrication treatment after the blanking process.

In the forming process, the pawl portion 20 is formed using the second mold 4 shown in FIG. can be done at the same time.

The piercing process involves the nail part 2 finished in the forming process.
Since only the dimensions of the center hole 16 are accurately finished based on the form of 0, it is possible to establish a precise diameter dimension that is compatible with the claw portion 20. Therefore, an excellent effect is achieved in that there is no need to perform the window processing work by mechanical cutting, which has conventionally been considered the most difficult due to the unique and special shape of the pole piece.

The ionizing process is carried out by the fourth mold 6 shown in FIG. 5, and the intermediate product 3 is placed in the die 50 of the fourth mold 6.
Since the straight land part is provided with an inner diameter smaller than the outer diameter dimension Dr of the claw part 20 of 00, the body 1
In addition to the sizing process to obtain zero flatness and parallelism, the outer surface 22 of the claw is ironed within one stroke, making it possible to avoid deterioration of the shape of the claw part 20 due to work hardening during the bending process, etc., and improve the final product. The dimensional accuracy of the barrel pole piece 400 can be stably maintained over a long period of time.

In addition, in the above embodiment, the pole piece 400 is the eighth,
Although the device has the same six claws as shown in FIG. 9, the claw portions, shapes, etc. are not limited to those of the above embodiment.

In addition, in the above embodiment, the pilot hole 15 of the center hole 16 was provided in the blanking process, but the point is that it is sufficient if the center hole 16 can be machined to a predetermined size in the piercing process. Finishing may be performed using strokes. That is, the third mold 5 in this case includes a piercing punch 52, a piercing die 51, and an intermediate product 30, as shown in FIG.
The stripper 53 is inserted into the ring 50 prior to the piercing punch 52 by means of a spring or the like and guides the intermediate product 300 and the piercing punch 52. Therefore, after positioning the intermediate product 300 transferred from the second mold 4 by the transfer means 7.7 using the ring 50 and the stripper 53, finishing punching is performed using the pierce punch 52 and the pierce die 51, thereby forming the center hole 16. can be finished to specified dimensions.

In this way, the piercing process is performed. According to the third mold 5 shown in FIG. 7, the shear surface of the center hole 16 is 90
% or more.

In addition, when machining the center hole in one stroke in the piercing process, the first mold 3 (
(see FIG. 2), the mandrel 33 is not necessary and the intermediate product 300 may be centered using the guide portion 35 of the die 30.

The second mold 4 may also be formed in the same manner. However, when the pilot hole 15 of the center hole 16 is provided in the blanking process as in the above embodiment, the intermediate product 300 can be centered relatively easily.

〔Effect of the invention〕

The present invention has the advantage of being able to provide a method for manufacturing a pole piece that is advantageous in equipment economy and can be processed quickly and with high precision over a long period of time.

[Brief explanation of drawings]

FIG. 1 is a conceptual diagram of a manufacturing apparatus suitable for carrying out the pole piece manufacturing method according to the present invention, and FIG. 2 is a side sectional view of a first mold for carrying out the bending process.
Figure 3 also shows the second stage for carrying out the forming process.
FIG. 4 is an explanatory view showing the progress of the forming process, etc.; FIG. 5 is a partially omitted side sectional view of the fourth mold corresponding to the progress of the ionizing process; FIG. 6 is an external view of the material etc. that changes in each process, and FIG. 7 is a side sectional view of a third mold according to another embodiment.
FIG. 8 is a plan view of the pole piece as a final product, and FIG. 9 is a side sectional view corresponding to the arrow line ■-■ in FIG. 1...Press@, Castle, 2...Transfables i
t+f・3...first mold, 4...second mold,
5... Third mold, 6... Fourth mold, 7... Transfer means, 8... Reversing means, 9... Lubrication processing device, 1
0... fuselage, 11... fuselage inner surface, 12... fuselage outer surface, 16... center hole, 18... groove, 20...
Claw portion, 22...Claw outer surface, 100...Raw material, 20
0...Material, 300...Intermediate product, 400...Pole piece.

Claims (5)

[Claims] (1) A blanking process in which a material of a predetermined shape is punched from raw materials, a lubrication treatment process in which a lubricant is applied to the material, and bending in which the body and claw portion are preformed by bending the material after the lubrication treatment. a forming process in which the dimensions of the preformed claw are shaped to a predetermined size; a piercing process in which the center hole is machined to a predetermined size based on the diameter of the claw formed to the predetermined size; and a piercing process in which the outer surface of the claw is The bending process, forming process, piercing process, and ioning process are continuously processed, consisting of an ioning process in which rolling process and sizing process to obtain flatness of the inner and outer surfaces of the body, etc. are performed within the same stroke. A method for manufacturing pole pieces characterized by the following. (2) In claim 1, the forming step is performed in an attitude in which the direction of the intermediate product is reversed so that the direction of the claw portion is opposite between the bending step and the forming step. A method for manufacturing pole pieces. (3) In claim 1 or 2,
Manufacture of a pole piece in which the ionizing step is processed using a mold having a straight land portion whose inner diameter is 0.3 to 0.8 mm smaller than the outer diameter of the intermediate product processed in the forming step. Method. (4) The method for manufacturing a pole piece according to any one of claims 1 to 3, wherein the forming step also forms a groove for positioning a coil attachment bobbin in the body at the same time. (5) The method for manufacturing a pole piece according to any one of claims 1 to 4, wherein the blanking step simultaneously forms a pilot hole for the center hole.