Classifications

• • B—PERFORMING OPERATIONS; TRANSPORTING
  • B21—MECHANICAL METAL-WORKING WITHOUT ESSENTIALLY REMOVING MATERIAL; PUNCHING METAL
  • B21H—MAKING PARTICULAR METAL OBJECTS BY ROLLING, e.g. SCREWS, WHEELS, RINGS, BARRELS, BALLS
  • B21H1/00—Making articles shaped as bodies of revolution
  • B21H1/02—Making articles shaped as bodies of revolution discs; disc wheels
  • B21H1/04—Making articles shaped as bodies of revolution discs; disc wheels with rim, e.g. railways wheels or pulleys
• • B—PERFORMING OPERATIONS; TRANSPORTING
  • B21—MECHANICAL METAL-WORKING WITHOUT ESSENTIALLY REMOVING MATERIAL; PUNCHING METAL
  • B21D—WORKING OR PROCESSING OF SHEET METAL OR METAL TUBES, RODS OR PROFILES WITHOUT ESSENTIALLY REMOVING MATERIAL; PUNCHING METAL
  • B21D53/00—Making other particular articles
  • B21D53/26—Making other particular articles wheels or the like
  • B21D53/261—Making other particular articles wheels or the like pulleys

Definitions

• the invention relates to a device for forming a rotationally symmetrical sheet metal body, for example a belt pulley blank with a central sheet metal body axis, which has an outer surface coaxial with the sheet metal body axis, with an U-shaped cross section open to the outside, and with a rotatably mounted embossing tool, wherein the tool rolls on the outer surface of the sheet metal body.
• a device for forming a rotationally symmetrical sheet metal body for example a belt pulley blank with a central sheet metal body axis, which has an outer surface coaxial with the sheet metal body axis, with an U-shaped cross section open to the outside, and with a rotatably mounted embossing tool, wherein the tool rolls on the outer surface of the sheet metal body.
• Such sheet metal bodies often serve as a blank for the production of pulleys.
• a tin pot is first pressed out of a sheet metal disc, the outer surface of which initially corresponds to a smooth cylinder jacket. Then a U-shaped profile open to the outside is rolled into the cylinder jacket, in which the desired profile is embossed in a further manufacturing step.
• the sheet metal body is rotatably clamped and a rotatably mounted, disk-shaped tool is applied, the tool and the sheet metal body rolling onto one another.
• the width of the tool is dimensioned such that it comes between the two U-legs when the feed is transverse to the sheet metal body axis.
• the desired profile depth is obtained by several complete rotations of the sheet metal body with simultaneous tool feed.
• the sheet metal body If the sheet metal body is subjected to radial pressure with the tool, the sheet metal tends to bear this pressure to avoid by forming a backlog in front of the point of intervention. This can lead to runout inaccuracies that must be corrected again.
• the back pressure is dependent on the size of the opening angle between the end faces of the sheet metal body and the tool. The larger the opening angle, the greater the back pressure. Due to the frontal engagement, the opening angle cannot be reduced in the desired manner due to the design.
• the invention has for its object to provide a device of the type mentioned, with which a reduction in the opening angle can be achieved.
• the tool is designed as an inner cylinder, which is arranged eccentrically on a rotatably mounted inner eccentric, and in that the axis of rotation of the inner eccentric is arranged eccentrically on a driving outer eccentric, which is rotatable coaxially to the sheet metal body axis, so that a relative movement of the Inside and outside eccentric produces a feed directed transversely to the sheet metal body axis.
• the invention has the advantage that the associated opening angle can be optimally reduced by the engagement of an inner and an outer cylinder.
• Another particularly great advantage can be seen in the fact that the sheet metal body can be arranged in a rotationally fixed manner, since the tool circles around the workpiece during the stamping process.
• the relatively complex, rotatable mounting of the workpiece can therefore be dispensed with.
• the workpiece had to be arranged on the free end of a shaft, or two shaft ends, which are mutually under axial pretension, wherein a deflection of the shaft end when the tool is pressurized from the side is not excluded could be.
• a rotating cash counter bearing for the cavity of the sheet metal body can be seen.
• the entire device is simplified in that there is no need to have a separate workpiece drive and no synchronization with the tool drive.
• the rotationally fixed mounting of the workpiece also facilitates the attachment and operation of a cooling device, so that the heat occurring during the deformation can be dissipated from the workpiece in a simple manner.
• the invention makes use of the idea that the tool feed and the retraction of the tool between the two U-legs of the sheet metal body or the opposite movement can take place by a relative movement between the inner and outer eccentric which can be controlled in a simple manner.
• a preferred further development of the invention consists in that it is provided with an exchangeable chuck for receiving different tool rings.
• This has the advantage that the changeover to different sheet metal diameters or poly-V profiles can be carried out in a simple manner and in a short time.
• the exchangeable chuck can thus be provided with different tool inner rings.
• the inner and outer eccentrics are resiliently biased against a relative movement. This optionally ensures that the inner eccentric is returned to the working position in which it is in engagement with the sheet metal body, or to a release position in which the device can be fitted.
• the control of the device is further simplified in that the brake with a limit switch. This has the advantage that the brake releases when a predetermined deflection or a predetermined tool advance is reached and the inner eccentric is returned to the starting position due to its pretension.
• a particularly effective and simple implementation of the brake is that it is designed as an eddy current brake.
• the brake may also be expedient for the brake to be designed as a mechanical brake, preferably as a shoe brake.
• FIG. 1 schematically shows a cross section through a detail of the device in the starting position.
• Fig. 2 shows schematically a cross section through the
• FIG. 3 shows a schematic side view of the detail in the working position.
• Fig. 4 shows schematically a view of the device in the starting position and
• FIG. 5 schematically shows a view of the device according to FIG. 4 in the working position.
• a pot-shaped sheet-metal body 1 which is arranged overall in a rotationally fixed manner, is illustrated, which serves as a blank for a drive wheel, for example a poly-V belt pulley. It has a disk part 3 which is arranged concentrically to a sheet metal body axis 2 and on the outer circumference of which a cylindrical jacket is arranged which is coaxial with the sheet metal body axis 2 and which has a U-shaped cross section open to the outside.
• the two U-legs 5 serve as lateral boundaries of a running surface 6, which is formed by the cylinder jacket part connecting the two U-legs 5.
• a tool designed as an inner cylinder 7 with the corresponding negative poly-V profile is rotatably arranged around the sheet metal body 1.
• 1 shows a starting position in which the inner cylinder 7 is located outside the U-leg 5. It is clear that the sheet metal body 1 can be brought into the inner cylinder 7 unhindered in this starting position.
• the inner cylinder 7 is radially offset from the starting position in such a way that it is located on one side of the sheet metal body 1 between the U-legs 5, so that the poly-V - Profile 8 engages with the tread 6.
• the longitudinal axis 9 of the inner cylinder 7 comes to lie next to the sheet metal body axis, ie the inner cylinder 7 rotates eccentrically around the sheet metal body 1 during a rotation.
• an interchangeable chuck 12 is also shown as an example, which receives the inner cylinder 7, which is designed as a circular ring.
• the changeable chuck 12 allows the inner cylinder to be exchanged if a change in the profile or the inner diameter is desired.
• the interchangeable chuck 12 is part of an external eccentric which is described in connection with FIGS. 4 and 5.
• the working position is shown in a side view.
• the U-legs 5 are cut away in the region of the point of engagement of the inner cylinder 7 with the tread 6.
• An opening angle between the running surface 6 of the sheet metal body 1 and the inner cylinder 7 is provided with the reference number 10. It is clear that the opening angle 10 becomes smaller the more the radii of the inner cylinder 7 and the tread 7 adapt. Furthermore, it is also evident that the minimum radius of the inner cylinder 7 is determined by the outer radius of the U-legs 5.
• FIGS. 4 and 5 illustrate the manner in which the inner cylinder 7 is driven and subjected to a radial feed.
• the inner cylinder 7 is located on an inner eccentric 11 eccentric to its axis of rotation 15, via which it is rotatably mounted on an outer eccentric 14.
• the outer eccentric 14 is arranged rotatably about the sheet metal body axis 2.
• the axis of rotation 15 of the inner eccentric 11 is arranged offset to the sheet metal body axis 2.
• the inner cylinder 7 therefore moves on a circular path.
• the inner eccentric 11 In the starting position shown, the inner eccentric 11 is rotated such that the inner cylinder 7 releases the sheet metal body 1 in the axial direction.
• the angular position in this starting position is determined by a stop 17.
• the inner eccentric 11 is held in this position with respect to the outer eccentric 14 by means of a spring 18.
• the outer eccentric 14 rotates, its rotational axis 15 moves on a circular path 20 around the sheet metal body axis 2.
• the inner cylinder 7 comes into engagement with the sheet metal body 1, as illustrated in FIG. 5.
• the longitudinal axis 9 of the inner cylinder 7 rotates on a circular path 13 coaxial to the sheet metal body axis 2.
• the inner cylinder 11 rolls on the fixed sheet metal body 1.
• the maximum rotation of the inner eccentric 11 relative to the outer eccentric 14 is determined by a further stop 21.
• the angular rotation of the inner eccentric 11 with respect to the outer eccentric 14 is achieved by a brake acting on the inner eccentric 11, which is designed such that it acts on the inner eccentric 11 regardless of position and exerts a torque.
• a brake acting on the inner eccentric 11 which is designed such that it acts on the inner eccentric 11 regardless of position and exerts a torque.
• it can be designed as a flying shoe brake. With a view to it is not shown in the figures. If a torque in the clockwise direction is exerted on the inner eccentric 11 when the outer eccentric 14 rotates counterclockwise, the latter executes a rotation around its axis of rotation 15 according to arrow 16, being deflected against the spring force until a further deflection by the further stop 21 is prevented.
• the outer eccentric 14 is driven by a cylindrical worm 23, the teeth of which mesh with a corresponding toothing on the cylindrical end face of the outer eccentric 14.
• the desired inner cylinder 7 is rotatably attached to the inner eccentric 11 with the help of the changeable chuck 12.
• the outer eccentric is driven by the worm 23 and set in rotation about the sheet metal body axis 2.
• the inner eccentric 11 bears against the stop 17, it rotates eccentrically around the sheet metal body 1 without the inner cylinder 7 touching the sheet metal body 1.
• the inner cylinder 7 is displaced by a deflection of the inner eccentric 11 on a circular path located further out, so that the poly-V profile 8 comes into engagement with the tread 6. Due to the rotary bearing of the inner cylinder 11, there is no relative movement between the inner cylinder 11 and the running surface 6. The larger the circular path traversed by the inner cylinder 7 becomes, the deeper the poly-V profile 8 is embossed into the running surface 6.
• a limit switch (not shown) is actuated, which causes the brake 22 to be released.
• the inner eccentric is returned to the starting position by the spring 18 and the sheet metal body 1 can be removed from the device.
• a pot-shaped blank is referred to in the above description, the invention is not limited to such a blank shape. It is also possible to produce a pot from a disc-shaped blank (not shown) by means of an inner cylinder tool, the inner cylinder tool having an essentially semicircular hollow profile instead of the poly-V profile shown in FIG. 1. Analogously, further processing such as upsetting, splitting, drawing in, polishing, etc. be carried out using appropriate tools.

Landscapes

• Engineering & Computer Science (AREA)
• Mechanical Engineering (AREA)
• Shaping Metal By Deep-Drawing, Or The Like (AREA)
• Bending Of Plates, Rods, And Pipes (AREA)
• Pulleys (AREA)
• Braking Arrangements (AREA)
• Press Drives And Press Lines (AREA)

Priority Applications (2)

Applications Claiming Priority (2)

Publications (1)

Family

ID=6342137

Family Applications (1)

Country Status (6)

Families Citing this family (2)

Citations (4)

Family Cites Families (1)

• 1987
  • 1987-12-08 DE DE3741596A patent/DE3741596C3/de not_active Expired - Fee Related
• 1988
  • 1988-12-07 WO PCT/EP1988/001116 patent/WO1989005203A1/de active IP Right Grant
  • 1988-12-07 JP JP1500061A patent/JPH03502663A/ja active Pending
  • 1988-12-07 AT AT89900228T patent/ATE68381T1/de active
  • 1988-12-07 EP EP89900228A patent/EP0390828B1/de not_active Expired - Lifetime
  • 1988-12-07 DE DE8989900228T patent/DE3865680D1/de not_active Expired - Fee Related
  • 1988-12-08 ES ES198888120547T patent/ES2026988T3/es not_active Expired - Lifetime
  • 1988-12-08 EP EP88120547A patent/EP0319979B1/de not_active Expired - Lifetime

Patent Citations (4)

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