JPH0220345B2 - - Google Patents

Description

[Detailed Description of the Invention] [Industrial Application Field] The present invention relates to a method for manufacturing a sheet metal poly-V pulley having a bearing, and more specifically, it relates to a method for manufacturing a poly-V pulley made of a sheet metal having a bearing, and more specifically, a plurality of poly-V grooves arranged at a predetermined pitch are formed in a peripheral wall portion, and ,
The present invention relates to an improvement in a method for manufacturing a sheet metal poly V pulley in which a bearing is fitted into a bearing fitting part on the shaft side connected to a peripheral wall part. [Prior art] Conventionally, this type of sheet metal poly-V pulley, that is, sheet metal material is deep drawn and reverse drawn to form a base part, a peripheral wall part, and a bearing fitting part on the shaft core side, respectively. Using a preformed member made of
A sheet metal poly V pulley has been commercialized in which a plurality of V grooves, so-called poly V grooves, arranged at a predetermined pitch are formed on the peripheral wall, and a bearing as a ready-made part is fitted into the bearing fitting part. It is widely used as an intermediate conduction V-pulley in, for example, vehicle engine equipment. Here, the sheet metal poly V with this conventional bearing
In the manufacture of pulleys, the above-mentioned preformed member is formed by plastically forming the base plate, the peripheral wall, and the bearing fitting part on the shaft core side, and then forming a poly V groove on the peripheral wall part and fitting the bearing into the preformed member. Regarding the fitting of ready-made bearings into joints, we mainly focus on maintaining accuracy after completion,
In other words, in order to match the rotation center of the molded poly V groove and the axis of the fitted ready-made bearing as much as possible, we first fit the ready-made bearing into the bearing fitting part. This is followed by plastic molding of a poly V groove onto the peripheral wall. [Problems to be Solved by the Invention] However, in the conventional method of manufacturing in this way, the shaft center of the ready-made bearing is first fitted into the bearing fitting portion. The preformed member itself is centered as a reference, and subsequent molding, in this case plastic forming of the poly V groove on the peripheral wall, is performed using this centered axial center point as a reference. The following problems arise due to the holding of the preformed member in the mold and the molding operation thereof. That is, as is well known, when plastically forming a poly V groove on a peripheral wall, the peripheral wall of the material that has been deep drawn is further formed to have a thicker wall, and then the thick peripheral wall is On the other hand, we are trying to form the poly V groove again, and the groove width and groove diameter of the poly V groove itself, as well as the pitch interval between the poly V grooves, are adjusted to about 5/100 mm, and especially by rotation. The shaft core needs to be finished with even higher precision, and when forming these grooves, the stress applied to the material will remain inside the material, and due to the influence of this residual stress, it will not be possible to achieve the desired result. There was a disadvantage that rotation center accuracy could not be obtained. [Means for Solving the Problems] In view of the above-mentioned problems in the prior art, the present invention aims to form a sheet metal poly-V pulley having a bearing from a sheet metal material as simply and easily as possible, and with high precision. The purpose of the present invention is to provide a manufacturing method with excellent mass productivity for constructing a support wall between a peripheral wall part where a poly V groove is formed and a bearing fitting part where a ready-made bearing is fitted. The folded bulges formed on the outer circumferential side and the inner circumferential side can absorb the internal stress of these peripheral wall parts and the bearing fitting part, respectively, so that the desired molding accuracy can be maintained. This is what I did. That is, the present invention includes a step of forming a cup-shaped material consisting of a substrate portion and a rough peripheral wall portion by deep drawing a sheet metal material, and a step of forming an inclined stepped portion on the rough peripheral wall portion to form a cup-shaped material consisting of a substrate portion and a rough peripheral wall portion. A step forming step in which the peripheral wall is divided into a poly V groove molded part on the opening edge side and a preformed part on the substrate side, and the preformed part and the substrate part are reversely drawn and folded inward, and the inclined An inner circumferential folded bulge protruding outward is formed between the stepped portion and the preformed portion, and the preformed portion is formed as a bearing support portion, and the base plate portion is formed as an inverted base portion, and further Preforming by squeezing to form an outwardly protruding outer peripheral side folded bulge between the inclined step part and the poly V groove molded part, and to make the inclined step part into a support wall part curved inward in a concave shape. a material forming step; a poly V groove forming step in which a poly V groove is appropriately formed in the poly V groove molded portion; and a bearing portion in which a central portion of the inverted substrate portion is cut and removed to form a bearing fitting portion. A sheet metal poly V pulley having a bearing, comprising a forming step and a bearing fitting step of supporting the bearing support part from the outer peripheral side and press-fitting the bearing inside the bearing fitting part. This is a manufacturing method. [Function] Therefore, in the method of the present invention, a cup-shaped material consisting of a substrate portion and a peripheral wall portion is used, and a poly V is formed on the peripheral wall portion.
A method for manufacturing a sheet metal poly V pulley in which a groove is formed and a bearing is fitted into the bearing fitting part of the shaft core, the peripheral wall part forming these poly V grooves and the bearing into which the bearing is fitted. Since the fitting part is connected to the supporting wall part which has a folded bulge part on the outer and inner periphery sides, this folded bulge part constitutes a kind of buffer part, and during manufacturing, the surrounding wall It is possible to effectively absorb and buffer internal stresses, such as molding stress and residual stress, which act on the parts and the bearing fitting parts, respectively, and as a result, sheet metal poly-V pulleys with this type of bearing can be obtained with high precision. It is. [Example] Hereinafter, a sheet metal poly V having a bearing according to the present invention
One embodiment of a method for manufacturing a pulley will be described in detail with reference to FIGS. 1 and 2. Figures 1a to 1h show a sheet metal poly V pulley according to this embodiment, in which a plurality of sheet metal poly V grooves lined up at a predetermined pitch are formed on the peripheral wall, and a sheet metal manufacturing method thereof. FIG. 3 is a half-cut sectional view showing processing modes at each main stage from raw material to product. That is, first, in FIG. 1, in the case of this embodiment method, a sheet metal material of a predetermined thickness is deep drawn to form a substrate portion 21 and a rough peripheral wall portion 22 having a flange portion 23 on the opening edge 22a side. A cup-shaped material forming step (FIG. 1A) in which a cup-shaped material 11 is formed by forming an inclined stepped portion 31 on the rough peripheral wall portion 22 of the cup-shaped material 11 , and forming the rough peripheral wall portion 22 into an opening edge. 22
A stepped cup-shaped material 12 is obtained by dividing it into a poly V-groove molded part 24 on the a side and a preformed part 25 on the substrate part 21 side (FIG. 2b); Preformed part 2 of material 12
5, and the substrate portion 21 side is reverse drawn and folded inward to form an inner peripheral folded bulge portion 41 protruding outward between the inclined step portion 31 and the preformed portion 25, respectively. The preformed part 25 is made into a bearing support part 42 and the board part 21 is made into an inverted board part 43, and these are further narrowed down to form a part between the poly V groove molded part 24 and the inclined stepped part 31 in the same way to the outside. By forming a protruding outer circumferential folded bulge 44,
A preformed material forming step (c in the same figure) in which a preformed material 13 is obtained by forming a preliminary support wall portion 45 in which the inclined step portion 31 between these folded bulging portions 41 and 44 is gently curved inward in a concave shape; After cutting and removing the flange portion 23 of the preformed material 13 , with an end portion 24a remaining on the outer circumference side folded bulge portion 44 side of the poly V groove molded portion 24,
A thickening preforming step (d in the same figure) to obtain a coarsely thickened molded material 14a as a thickened bulge portion 51 in which the same poly V-groove molded portion 24 is bent toward the outer periphery by an amount corresponding to the thickened wall. ), and the thickened bulge portion 5 of the coarse thickened molded material 14a .
1 is pressed to form a poly V-groove molded thick part 52 thickened to correspond to the degree of bending, and at the same time, a poly V-groove molded thick part 52 is formed near the end 24a. A thickening forming step (e in the figure) for obtaining a thickened molded material 14 by forming a reference groove 62 ; 62 as a molding reference point, the outer circumferential folded bulge 44 side and the opening edge 2
On both sides of the 2a side, there are rising ears 63,
A poly V groove forming step (FIG. f) for obtaining a coarse poly V grooved material 15a in which a plurality of poly V grooves 61 having a plurality of poly V grooves 64 arranged in parallel with each other are formed; Bearing support part 4 of material 15a
2, and reshaping the support wall portion 45,
The central part side of the reversible board part 43 is connected to the bearing support part 4
A bearing part forming step (g) in which the bearing holding part 71 is left and removed at the inner circumferential side connecting part with 2, and a bearing fitting part 81 is formed in the same part to obtain a poly V grooved material 15 (FIG. 3g). Bearing press-fitting and crimping, in which the ready-made bearing 91 is press-fitted and crimped into the bearing support part 42 constituting the bearing fitting part 81 of the poly-V grooved material 15 until it abuts the bearing holding part 71. The attaching process (h in the same figure) and the following processes are carried out in sequence, and the sheet metal material is processed and formed through these processes to achieve the desired shape.
A sheet metal V-pulley 100 having a poly V-groove 61 on its outer periphery and a bearing 91 fitted on its shaft core is manufactured. Further, FIGS. 2 a1 to 2 i1 are cross-sectional explanatory views sequentially showing more specific manufacturing steps of the method for manufacturing the sheet metal V-pulley 100, and details of each step will be described below. (1) Cup-shaped material forming process (Fig. 1 a) In this cup-shaped material forming process, Fig. 2 a1
As shown in the figure, a sheet metal material with a predetermined thickness and outer diameter is used as a molding material, and both movable and fixed inner parts,
The cup-shaped material 11 consisting of the base plate part 21 and the rough peripheral wall part 22 is formed by deep drawing to a predetermined outer diameter and drawing depth using the outer drawing dies 111, 112 and the holding die 113. At this time, the opening edge 22 of the rough peripheral wall 22
A flange portion 23 made of surplus material accompanying the drawing process remains in the area a. (2) Step forming step (Fig. 1 b) In this step forming step, as shown in Fig. 2 b1, the inner pressing molds 211 and 2 are overlapped with each other.
12, with the cup-shaped material 11 fitted and held, the rough circumferential wall portion 2 of the cup-shaped material 11 on the substrate portion 21 side is pushed by the preliminary stage pushing roller 213.
Part 2 is pre-rolled and an inclined stepped part 31 is formed in the same part.
is molded to obtain a stepped cup-shaped material 12 . That is, in this step, as a result, the inclined step portion 31 is formed on the rough peripheral wall portion 22 of the cup-shaped material 11 .
By forming this rough peripheral wall portion 22, an opening edge portion 22a whose diameter is increased by the inclined step portion 21 is formed.
It is divided into a poly V-groove molded part 24 on the side, and a preformed part 25 on the side of the substrate part 21, which has a smaller diameter than this. (3) Preformed material forming process (Fig. 1 c) In this preformed material forming process, first, as shown in Fig. 2 c1, the stepped With the cup-shaped material 12 fitted and held, the inner drawing die 3
13, the preformed part 25 and the base plate part 21 of the stepped cup-shaped material 12 are reverse drawn to a predetermined inner diameter and drawing depth, and folded inward to form the inclined stepped part 31 and the base part 21. Preforming part 25
An inner circumferential folded bulge portion 41 protruding outward is formed between the preformed portion 25 and the base plate portion 21 to form a bearing support portion 42 and a reverse base plate portion 43, respectively. Therefore, in this step, the inclined step portion 31 and the preformed portion 25 are formed into an acute angle shape in an inverted state. When reverse drawing is performed over such a large angle range, a strong internal stress is generated in the material, but in this case, the folded bulge 41 on the inner circumferential side that intentionally protrudes outward at this acute-angled bent portion Since the internal stress is bent at an acute angle, it is easy to release the internal stress, and moreover, the folded bulge forms a kind of buffer. This allows the molding to be concentrated in the portion 41, thereby making it possible to perform the molding with even higher accuracy and ease. In addition, as shown in FIG.
Then, while the stepped cup-shaped material 12 that has been subjected to reverse drawing is fitted and held, the inner drawing die 313 is inserted.
By narrowing this down further, this time, an outer circumferential folded bulge 44 protruding outward similar to the above is formed between the poly V groove molded part 24 and the inclined step part 31, A preformed material 13 is obtained by forming a preliminary support wall portion 45 that is gently curved inward in a concave state by the inclined step portion 31 between the folded and bulged portions 41 and 44. In this process, once in the previous stage,
Inner circumferential folded bulge 4 narrowed into an acute angle
1 is pushed open again to form a preliminary support wall portion 45 that is gently curved inward in a concave shape together with the folded bulge portion 44 on the outer peripheral side.
The internal residual stress concentrated in the folded bulge 41 on the inner peripheral side is appropriately dispersed and released, and the molding parts become more familiar, so that there is no risk of hindering high-precision molding. (5) Thickening preforming process (Fig. 1 d) This thickening preforming process and the next thickening forming process are used to form poly V grooves when using a thin sheet metal material. In order to prevent the peripheral wall that formed from becoming thinner and lacking in strength, only the peripheral wall is made thicker in advance, and this process is not necessarily necessary if a thick sheet metal material is used. . However, in this example, in order to reduce the weight and cost of the product by using a thin sheet metal material,
Each of these processes is adopted. Therefore, in this thickening preforming step, first , as shown in FIG. The poly V-groove molded part 24 is sheared from a predetermined dimensional position using a roller 413 to remove and shape the flange part 23 and the excess material, and then, as shown in FIG. 2 d2, and external presser molds 414 and 4
15 and 416 concentrically, and the end portion 24a is tightly held between the inner and outer holding molds 415 and 416, the poly V groove is formed by the outer drawing mold 417. Molding part 2
4 is bent toward the outer periphery by an amount equivalent to the thickness increase described later to form a thickening bulge portion 51, and in this way, a rough thickening molded material 14a is obtained. (6) Thickening forming step (Fig. 1 e) In this thickening forming step, first, as shown in Fig. 2 e1, the rough thickening forming material 14 a is fitted into the preforming mold 511. Along with the same material 1
The preliminary support wall portion 45, the inner circumferential side folded bulge portion 41, the bearing support portion 42, and the inverted base plate portion 43 of 4a are concentrically clamped and held from the outside by the external holding mold 512, and the thickening is performed. As for the bulging portion 51, its opening edge, that is, the aforementioned opening edge 22a is abutted against and supported by the abutment step portion 511a of the preforming mold 511. In this state, the bulging tip of the thickening bulge 51 is pressed by the poly V-groove preforming roller 513 which also serves as a thickening roller.
Here, the opening edge 12 of this thickened bulge 51
a is abutted against and supported by the abutment stepped portion 511a, so that the roller surface 51 of this roller 513
3a, the thickened bulging portion 51 is gradually rolled and pressed and subjected to plastic flow forming, thereby achieving thickening to a predetermined thickness at the same portion, and at the same time, the protruding forming surface 513b of the roller 513. As a result, the thickened bulging portion 51, and furthermore, the end portion 24a of the thickened poly V-groove molded thick portion 52, which is close to the outer circumferential folded bulging portion 44, is preliminarily narrowed from the outer periphery. Rolled and poly V in the same part
Reference groove portion 62 serving as a forming reference point for groove forming
is formed in advance, and in this way, a thickened molded material 14 is obtained. In this case, the rolling for increasing the thickness of the poly V-groove molded thick portion 52 and the rolling for the reference groove 62 performed at the same time are due to the presence of the outer circumferential side folded bulge 44. , internal stress is effectively absorbed, and there is no risk of the same stress affecting other molded parts. (6) Poly V groove forming process (Fig. 1 f) In this poly V groove forming process, first, Fig. 2 f1
And as shown in f2, for the combination of the preforming mold 511 and the forming roller 513 described above, the first and second poly V-groove preforming molds 515, 517 and the forming roller 51 are eccentrically arranged.
6,518 combinations, and with the same clamping pressure as described above being maintained, the reference groove portion 62 is utilized as one molding reference point for poly V groove molding. For the poly V groove formed thick part 52, a plurality of parallel preliminary poly V grooves 61a, 61b are formed as first and second preliminary rolling so as to gradually approach a predetermined size and shape. As we narrow it down little by little,
The outer circumferential folded bulge 44 side and the opening edge side 1
The rising ears 63 and 64 are formed on the 2a side so as to gradually rise. That is, for the thickened poly V-groove molded part 52, the reference groove part 62 becomes the molding reference point for poly V-groove molding here, and
As described above, due to the presence of the outer circumferential folded bulge portion 44, internal stress is effectively absorbed, and the preliminary poly V grooves 61a and 61b as preliminary rolling of these first and second portions are formed. It is possible to form a plurality of strips in parallel with each other with just enough thickness and with accurate size and shape arrangement. Thereafter, as shown in FIG. 2 f3, the combination of the poly V-groove mold and the forming roller is rearranged into a combination of the eccentric poly V-groove finishing mold 519 and the poly V-groove finishing molding roller 520, and this is done. However, while maintaining the same clamping pressure as above, the plurality of parallel preliminary poly V grooves 61b in the second preliminary rolling are narrowed deeper from the outer periphery by the V groove finishing forming roller 520, and finished. By rolling, a plurality of parallel poly V-grooves 61 can be formed with high accuracy on the same poly V-groove molded portion 52, and in this way, a rough poly V-groove material 15a is obtained. (7) Bearing part forming process (Fig. 1 g) In this bearing part forming process, first, as shown in Fig. 2 g1, the coarse poly V-grooved material 15 a
, inner presser molds 611, 612 and outer presser mold 613
The bearing support part 42 and the support wall part 45 of the same coarse poly V-grooved material 15a are held firmly in the same manner as above by the shaping roll 61.
4, it is once reshaped and the dimensions and accuracy are corrected. Next, as shown in FIG. 2g2, the bearing holding part 7 is attached to the peripheral part of the inverted base plate part 43 which is connected to the bearing support part 42 of the rough poly V-grooved material 15a.
1 is firmly held between another inner presser die 615 and an outer presser die 616, the center side of the reversible substrate portion 43 is cut by a shearing die 617 leaving the coaxial bearing presser portion 71. The bearing fitting portion 81 is formed in the portion including the bearing support portion 42 and the bearing holding portion 71, and the poly V is removed.
A grooved material 15 is obtained. (8) Bearing fitting process (Fig. 1 h) In this bearing fitting process, first, as shown in Fig. 2 h1, the support wall portion 45 of the poly V grooved material 15 is placed between the inner holding die 711 and the outer holding die 711. It is firmly clamped by the presser die 712 in the same way as above, and
The outer peripheral surface base of the bearing support part 42 is held by the inner pressing die 71.
1 and the bearing holding part 71 of the bearing support part 42 are held in place by the inner holding die 713, and in this state, using the pushing die 714, the bearing fitting part 81 is pressed and held. The ready-made bearing 91 is press-fitted into the constituting bearing support part 42 until it contacts the bearing holding part 71, and then caulked and fitted. In this bearing fitting process, the outer circumferential surface base of the bearing support part 42 itself is held by the inner holding mold 711
Since the bearing holding part 71 is held by the inner holding die 713, press-fitting and caulking of the ready-made bearing 91 are extremely smooth and easy. Moreover, since the folded bulge part 41 on the inner peripheral side is provided between the compressed support wall part 45, the internal stress generated during press-fitting and caulking can be effectively absorbed here as well. There is no risk of stress affecting other molded parts. That is, as described above, a sheet metal V having a poly V groove 614 on the outer periphery and a bearing 91 fitted in the shaft core, which is the object of this embodiment, is manufactured.
The pulley 100 can be constructed with high precision. [Effects of the Invention] As detailed above, according to the method of the present invention, a cup-shaped material consisting of a base plate portion and a peripheral wall portion is used, a poly V groove is formed on the peripheral wall portion, and a shaft on which the base plate portion is molded is formed. In a method for manufacturing a sheet metal poly V pulley configured by fitting a bearing into a bearing fitting part of a core part,
By reverse drawing processing of deep-drawn cup-shaped material,
When molding the peripheral wall part forming the poly V groove and the bearing fitting part into which the bearing is fitted, folded bulges are provided on the outer and inner peripheral sides of the support wall part that connects these two parts. Therefore, this folded bulging part acts as a kind of buffer part, and acts on the peripheral wall part and the bearing fitting part respectively during plastic forming of the poly V groove on the peripheral wall part and press fitting of the bearing. This makes it possible to effectively absorb internal stresses caused by molding, such as molding stress and residual stress, which not only makes the molding process itself easier, but also improves the dimensional accuracy of each molded part, especially the poly V groove and the rotation of the bearing. The center accuracy, that is, the axis accuracy can be greatly improved, and the sheet metal poly-V pulley having this type of bearing can be mass-produced with high accuracy.

[Brief explanation of drawings]

The attached drawings show an embodiment of the method for manufacturing a sheet metal poly-V pulley with a bearing according to the present invention, and Figures 1a to 1h sequentially show processing modes at each major stage from sheet metal material to product. Each is a half-cut sectional view, and FIGS. 2A1 to 2H1 are half-cut sectional views showing more specific manufacturing steps of the same manufacturing method. 11 ... Cup-shaped material, 12 ... Stepped cup-shaped material, 13 ... Preformed material, 14 ... Thickened molded material, 14 a... Rough thickened molded material, 15 ... Poly V grooved material, 15 a... Rough Poly V grooved material, 100…
A sheet metal V pulley with a poly V groove and a bearing fitted into it. 21... Substrate part, 22... Rough peripheral wall part, 24... Poly V groove molded part, 25... Preformed part.
31... Slanted stepped portion. 41, 44... Inner circumferential side, outer circumferential side folded bulge part, 42... Bearing support part, 43... Inversion board part, 45... Support wall part. 51...Thickened bulge, 5
2...Thickened poly V-groove molded part. 61...PolyV
Groove, 62...Reference groove part. 71...Bearing holding part. 81...
Bearing fitting part. 91...Ready-made bearing. 111...Inner drawing die, 112...Outer drawing die, 113...Inner pressing die. 21
1,212...Inner pressing die, 213...Preliminary stage pushing roller. 311, 312...inner pressing type, 313...inner drawing type. 411, 415, 416...External presser type, 41
2,414...Inner pressing mold, 413...Shearing roller, 4
17...Outer drawing mold. 511,515,517...
Preforming mold, 512... External pressing mold, 513, 51
6,518... Preforming roller, 519... Finishing mold, 520... Finishing forming roller. 611,61
2,615...Inner press type, 613,616...External press type, 617...Shear type. 711, 713...inner presser type, 712...outer presser type, 714...push type.

Claims (1)

[Scope of Claims] 1. A cup-shaped material forming step of deep drawing a sheet metal material to form a cup-shaped material consisting of a substrate portion and a rough peripheral wall portion, and forming an inclined stepped portion on the rough peripheral wall portion, a step forming step in which the rough peripheral wall is divided into a poly V groove molded part on the opening edge side and a preformed part on the substrate side; An inner circumferential folded bulge protruding outward is formed between the inclined step part and the preformed part, and the preformed part is formed in the bearing support part, and the base plate part is formed in the inverted base part. Further narrowing is performed to form an outwardly projecting folded bulge on the outer peripheral side between the inclined step part and the poly V-groove molded part, and also to form a support wall part in which the inclined step part is curved inward in a concave shape. a forming step of forming a molding material; a poly V groove forming step of appropriately forming a poly V groove in the poly V groove molded portion; and a bearing of forming a bearing fitting portion by cutting and removing the central portion of the inverted substrate portion. A sheet metal poly V having a bearing, comprising a step of forming a bearing support portion from an outer peripheral side and a bearing fitting step of press-fitting a bearing inside the bearing fitting portion. How to manufacture pulleys.