US3572077A

US3572077A - Apparatus for a continuous swaging of rod-shaped workpieces

Info

Publication number: US3572077A
Application number: US817356A
Authority: US
Inventors: Bruno Kralowetz; Gottfried Blaimschein
Original assignee: Individual
Current assignee: Individual
Priority date: 1968-05-03
Filing date: 1969-04-18
Publication date: 1971-03-23
Anticipated expiration: 1988-03-23
Also published as: GB1201888A; AT276009B; FR2007730A1; DE1915656A1; JPS4948392B1

Abstract

At least one swaging unit is provided, which defines a feed path along which a rod-shaped workpiece is axially movable in said unit. Each of said units comprises a frame, a plurality of guides spaced around said path and extending substantially radially with respect to said path and rotatably mounted in said frame on axes which extend transversely to said path, a plurality of dies which consist of connecting rods and are slidably mounted in respective ones of said guides, a plurality of eccentric shafts mounted in said frame and extending parallel to said path and operatively connected to respective ones of said dies to reciprocate the same in said guides, and oscillating means for imparting to each of said dies an oscillating pivotal movement about the axis of rotation of the respective guide.

Description

United States Patent [72] inventors Bruno Kralowetz Weinleiten 142, Steyr, St. Ulrich; Gottfried Blaimschein, Punchstrasse 2,

Steyr, Austria [2]] Appl. No. 817,356 [22] Filed Apr. 18, 1969 [45] Patented Mar. 23, 1971 [32] Priority May 3, 1968 [3 3] Austria [3 l A4253/68 [54] APPARATUS FOR A CONTINUOUS SWAGING OF [5 6] References Cited UNITED STATES PATENTS 3,165,012 1/1965 Kralowetz 72/402 3,396,570 8/1968 McCardell... 72/402 3,460,370 8/1969 Kralowetz 72/408 Primary Examiner-Lowell A. Larson Att0rneyKurt Kelman ABSTRACT: At least one swaging unit is provided, which defines a feed path along which a rod-shaped workpiece is axially movable in said unit. Each of said units comprises a frame, a plurality of guides spaced around said path and extending substantially radially with respect to said path and .rotatably mounted in said frame on axes which extend transversely to said path, a plurality of dies which consist of connecting rods and are slidably mounted in respective ones of said guides, a plurality of eccentric shafts mounted in said frame and extending parallel to said path and operatively connected to respective ones of said dies to reciprocate the same in said guides, and oscillating means for imparting to each of said dies an oscillating pivotal movement about the axis of rotation of the respective guide.

PATENTED mm. 35721077 V SHEEI1UF4 FIG] A c 3 {W l x M u 13 I INVENTORS B O K RALOWE TZ PATENTED M23 l97| 3.572 077 sum 2 OF 4 INVENTORS B Rulvo WRArL M/FTZ 60W 1 ED BLMMKHEIN APPARATUS FOR A CQNTllNUQlUS SWAGKNG F ROD- SHAPED WQltlltlPlllECES This invention relates to an apparatus for a continuous s /aging of rod-shaped workpieces, which apparatus consists of preferably at least two swaging units, which comprise dies consisting of connecting rods that extend radially with respect to the axis of the workpiece and aredriven each by an eccentric shaft and slidable in a rotatable guide.

lrt the previously known apparatus of this kind, the eccentric shafts extend transversely to the axis of the workpiece and the axes-of rotation of the guides extend parallel to the eccentric shafts and also transversely to the axis of the workpiece. As a result, the dies consisting of connecting rods perform not only a sliding movement toward the workpiece but also a pivotal movement generally in the longitudinal direction of the workpiece and about the axes of rotation of the guides so that the dies not only shape the workpiece to reduce its cross section but also impart a feed movement to the workpiece. The use of a plurality of such swaging units enables a considerable reduction in cross section so that such apparatus can be used instead of a rolling mill train and requires much less power and much lower prime costs. Because the axis of each eccentric shaft lies in a plane which is normal to the axis of the workpiece, however, the means for driving the eccentric shafts must comprise bevel gear trains, which involve a relatively complicated and expensive structure particularly with units comprising more than two dies. The provision of common drive means for two or more swaging units is rendered more difficult. Whereas the feed rate of the workpiece can be adjusted by the selection of the eccentricity, the lever ratio acting on the dies and the speed of the eccentric shafts, there is the further disadvantage that it is not possible to change the feed rate of the workpiece during the operation although this is often required.

Other swaging machines are known in which each die comprises an elliptic chuck, which comprises a cylindrical spider, which embraces the eccentric member of the respective eccentric shaft and is displaceable transversely to the axis of the die and movable in correspondingly shaped discs, and in which the eccentric shafts extend radially to the axis of the workpiece. The dies are mounted in stationary radial guides of the swaging box so that they perform only sliding movements which are radial to the workpiece, but do not perform a pivotal movement. Hence, an additional feeding device is required and the dies cannot follow the stretching movements performed by the workpiece when its cross section is greatly reduced.

it is an object of the invention to eliminate these disadvantages and to provide for a continuous swaging of rodshaped workpieces an apparatus in which the structural expenditure for the means for driving the dies is much reduced although the dies impart the required feed movement to the workpiece and the feed rate of the workpiece can be varied during operation.

in an apparatus of the kind which has been defined first hereinbefcre, this object is accomplished according to the invention in that the axes of the eccentric shafts extend in known manner parallel to the axis of the workpiece, the axes of rotation of the guides extend also in known manner transversely to the axis of the workpiece, and the sliding movement of the dies in a radial direction with respect to the workpiece is superimposed by an oscillating pivotal movement about the axis of rotation of the guides, preferably through a variable angle. Because the axes of of the eccentric shafts extend parallel to the axis of the workpiece, simple spur gears may be used to drive the eccentric shafts so that a relatively simple structure results, which enables the use of several dies in each swaging unit without difficulty. Because the dies are mounted in rotatable guides and the axes of rotation of these guides extend transversely to the axis of the workpiece, an additional pivotal movement in planes extending through the axis of the workpiece may be imparted to the dies so that they impart the desired feed movement to the workpiece. it will be understood that this pivotal movement cannot be accomplished merely by the drive imparted by the eccentrics to the dies, which consist of connecting rods. A separate drive means must be provided for this purpose and affords the advantage that the feed rate can be changed without difficulty.

in a development of the invention, the means for imparting a pivotal movement to a die comprises a plunger, which is spaced from the guide and extends parallel to the eccentric shaft and is adapted to perform a reciprocating movement in synchronism with the rotation of the eccentric shafts, the respective die engages said plunger, and each die comprises in known manner an elliptic chuck, which comprises a cylindrical spider, which is slidable transversely to the axis of the die and embraces the eccentric member and is held between correspondingly shaped discs. The dies must not perform a pivotal movement in a plane which is normal to the axis of the workpiece and to the axis of the eccentric because they are held at two points as they engage the plunger and as they are mounted in the guide. Any movement in said plane is thus inherently precluded, Because the dies comprise elliptic chucks, they will not move transversely to the eccentric shafts by which they are driven. The reciprocating movement of the plungers imparts a pivotal movement to the dies in the radial planes which are determined by the axes of the eccentric shafts and the axis of the workpiece. The cylindrical shape of the spiders of the elliptic chucks enables a pivotal movement of the dies adjacent to the eccentric member. This pivotal movement is supplemented by a slight axial movement relative to the eccentric member.

The reciprocating axial movement may be imparted to the plunger by various means. it will be particularly desirable to hold the plunger against rotation by the die and to provide said plunger with a screw thread, which is threaded into a nut, which by means of a crank arm and a coupler or the like is articulatedly connected to a pivoted elliptic chuck, which is movable in crossing guides and comprises a spider embracing an additional eccentric member mounted on the eccentric shaft so that the crank arm, coupler and elliptic chuck form an articulated quadrangle. The additional eccentric members on the eccentric shafts impart an oscillating pivotal movement to the elliptic chucks. Each of said elliptic chucks forms one link of the articulated quadrangle. As a result, the crank arm performs a similar pivotal movement and the nut performs an oscillating rotational movement and imparts the desired reciprocating axial movement to the plunger. This arrangement affords the advantage that the movement of the plunger is directly derived from the eccentric shaft, the need for other drive means is eliminated and the movement of the plunger is positively dependent on the rotation of the eccentric shaft.

In a development of the invention, all elliptic chucks for driving said plungers are jointly pivoted to an adjusting ring which is rotatable about the axis of the workpiece. An adjustment of this ring in one direction or another will change the position of the elliptic chucks relative to the additional eccentric members on the eccentric shafts so that the spiders then perform their sliding movement enforced by the eccentric members in another range of the elliptic chucks and the lever ratio of the elliptic chucks and the range of the pivotal movement thereof are changed. The range of this pivotal movement will directly control the angle of the rotation of the nuts on the plungers and also the displacement of the latter so that the adjusting ring can be adjusted to change the amount of the pivotal movement of the dies and the feed rate of the workpiece. This adjustment and change can readily be effected during the movement of the dies i.e., when the apparatus is in operation.

The dies are held on the plungers for movement therewith in both directions of the axial movement of said plungers and with spring means interposed so that differences between the pivotal movement of the dies and the feed or stretching movement of the workpiece can be compensated and damage to the workpiece or to parts of the workpiece, which damage could otherwise occur, can be avoided.

Because the eccentric shafts extend, in accordance with the invention, parallel to the axis of the workpiece, two swaging units may be provided with a common transmission, which is disposed between the swaging units and which consists of a circular series of spur gears, which are spaced around the workpiece axis and mesh with each other, alternate ones of said spur gears being arranged to drive eccentric shafts of one swaging unit and the other, respectively, one of said spur gears being driven from a motor, and idlers being interposed, if desired, between said motor and said one spur gear. This arrangement constitutes a relatively simple double unit comprising a multiplicity of dies. The two swaging units may even be flanged to the housing of the transmission which is disposed between them. It will also be within the scope of the invention to provide an apparatus which consists of one swaging unit and the associated transmission.

The invention is shown by way of example on the accompanying drawings, in which:

FIG. 1 is a sectional view taken on line II of FIG 4 and showing one part of one unit of a swaging apparatus consisting of two swaging units;

FIG. 2 is a sectional view taken on line II-II in FIG. 1;

FIG. 3 is a sectional view taken on line III-III in FIG. 1;

FIG. 4 is an end elevation showing on a reduced scale the entire apparatus; and

FIG. 5 is a top plan view showing the apparatus.

The apparatus comprises two swaging units A, B, which have approximately mirror symmetry and are coaxially disposed and flanged to the housing of a common transmission C, which is disposed between said units. Each swaging unit comprises six dies 1, which are driven by eccentric shafts 2. The latter are regularly spaced around the workpiece axis, which coincides with the main axis of the apparatus, and extend parallel to said axis. The eccentric shafts of swaging unit A are staggered by an angle of 30 from those of unit B so that the transmission C comprises a total of 12 spur gears 3, 4 disposed on a common pitch circle and in mesh with each other. The spur gears 3 drive the eccentric shafts 2 of unit A and the spur gears 4 drive the eccentric shafts 2 of unit B. The entire apparatus is driven from amotor 5 by means of

idlers

6, 7. The eccentric members 8 in each unit are arranged so that three dies spaced 120 apart blow at the same time whereas the interposed dies are retracted from the workpiece at that time.

The dies I extend radially to the workpiece axis or main axis of the machine and comprise each an elliptic chuck, which comprises a cylindrical spider 9, which embraces the eccentric member 8 and is displaceable transversely to the die axis and held between correspondingly shaped discs 10. The dies consist of connecting rods and are also slidable in rotary guides 11, which have a spherical outside surface so that they can rotate to all sides and particularly about an axis which is transverse to the workpiece axis or main axis of the machine. Each die extends beyond the elliptic chuck thereof to form a fork 12, which straddles a plunger 13, which is reciprocable parallel to the axes of the eccentric shafts 2. The fork l2 bears by means of disc springs 14 on the plunger 13 for movement therewith in both directions of the axial movement of said plunger. The reciprocation of the plunger 13 imparts to the die 1 an oscillating pivotal movement about the workpiece axis or main axis of the apparatus, which axis extends through the center of the spherical guide 11. As a result, the desired feed movement in the direction of the arrow is imparted to the workpiece. This pivotal movement is superimposed on the radial sliding movement imparted to the dies by the eccentric members 8.

The plunger 13 is provided with screw threads 15, on which a two-part nut 16 is threaded, which is connected to the hub 17 of a crank arm 18 for rotation therewith. The crank arm is linked by a coupler 19 to an elliptic chuck 20 (FIG. 2). The spider 21 of said elliptic chuck 20 embraces an additional eccentric member 22, which is mounted on the eccentric shaft 2. All elliptic chucks 20 are pivoted to a common adjusting ring 23, which is rotatable about the workpiece axis or main axis of the apparatus.

It is apparent from FIG. 2 that the crank arm 18, the coupler I9 and the elliptic chuck 20 form an articulated quadrangle, and the rotation of the eccentric shaft 2 imparts to the elliptic chuck 20 a pivotal movement, which is transmitted by the coupler 19, the crank arm 18 and its hub 17 to the nut 16. The oscillating rotation of the nut imparts a reciprocating axial movement to the plunger 13, which is held against rotation by the die fork 12. A rotation of the adjusting ring 23 will change the position of the elliptic chuck 20 relative to the additional eccentric 22 of the eccentric shaft 2 so that the range of the sliding movement of the spider 21 of the elliptic chuck 20 is changed and with it the range of the pivotal movement whereas the eccentricity remains the same. With the range of the pivotal movement, the displacement of the plunger 13 and consequently the feed rate of the workpiece is changed too. Because the adjusting ring 23 is common to all dies, the adjustment is the same for all dies.

One of the eccentric shafts 2 which are associated with each set of three dies 1 blowing at the same time or retracted from the workpiece at the same time is eccentrically mounted in a rotatable adjusting housing 24. Because this eccentric shaft is eccentrically mounted in the adjusting housing, the latter tends to rotate in reacting to the swaging force but is held against such rotation by a piston 26, which is slidable in a cylinder 25 and to which hydraulic pressure is applied. The piston rod 27 of said piston is linked to' the adjusting housing 24 (FIG. 3). Hence, the swaging pressure or the reaction force due to said swaging pressure can be hydraulically sensed and an overload condition can be indicated by an alarm signal when a predetermined limit is exceeded. In case of a power failure, the dies 1 which are blocked at the workpiece can be released from the latter in that the cylinder 25 is relieved from the hydraulic pressure. The desired position of the adjusting housing 24 is determined by a stop 28, which can be adjusted by means of a handwheel 30 and a worm gearing 29. This stop 28 may be adjusted in dependence on the dimensions of the workpiece and the desired reduction in cross section. Whereas this adjustment will change the stroke position only of one die of a set of three dies, the use of three dies in swaging the workpiece to a cylindrical cross section will cause the cross section of the workpiece to be changed in diameter if one die is displaced. The resulting displacement of the workpiece axis relative to the desired position is negligibly small. The displacement of the eccentric shaft 2 relative to the spur gear 4 caused by the rotation of the adjusting housing 24 is enabled and compensated by a coupling 31 of known type.

We claim:

1. Apparatus for a continuous swaging of rod-shaped workpieces, which comprises:

at least one swaging unit defining a feed path along which a rod-shaped workpiece is axially movable through said unit, said unit comprising;

a frame;

a plurality of guides spaced around said path and extending substantially radially with respect to said path and rotatably mounted in said frame on axes which extend transversely to said path;

a plurality of dies which consist of connecting rods and are slidably mounted in respective ones of said guides;

a plurality of eccentric shafts mounted in said frame and extending parallel to said path and operatively connected to respective ones of said dies to reciprocate the same in said guides; and

oscillating means for imparting to each of said dies an oscillating pivotal movement about the axis of rotation of the respective guide.

2. Apparatus as set forth in claim 1, which comprises adjusting means for varying the angle of said oscillating pivotal movement imparted to said dies by said oscillating means.

3. Apparatus as set forth in claim I, in which said oscillating means comprise:

a plurality of plungers, each of which is associated with and spaced from one of said guides and extends parallel to the associated eccentric shaft;

reciprocating means for imparting to said plungers a reciprocating movement in response to the rotation of 5 said eccentric shafts; g each of said eccentric shafts carries an eccentric member; each of said dies comprises an elliptic chuck having two discs formed with respective grooves facing and crossing each other and a cylindrical spider, which is disposed between said discs and slidably engages said grooves and which embraces said eccentric member on the eccentric shaft associated therewith; and

each of said plungers engages said spider of said die associated therewith.

4. Apparatus as set forth in claim 3, in which:

each of said plungers engages the associated die so that a rotation of said plunger is prevented;

. said reciprocating means comprise;

screw threads on each of said plungers;

a plurality of nuts. each of which is threaded on one of said screw threads;

a plurality of linkages, each of which consists of a crank arm connected to one of said nuts and a coupler connected to said crank arm;

a plurality of elliptic chucks pivoted in said frame and comprising each a spider;

a plurality of additional eccentric members mounted on respective ones of said eccentric shafts and embraced 7 each by one of said spiders of said pivoted elliptic chucks;

and said crank arm, coupler and pivoted elliptic chuck forming an articulated quadrangle.

5. Apparatus as set forth in claim 4, in which:

an adjusting ring is mounted in said frame for rotation about said path; and

said pivoted elliptic chucks are pivoted to said adjusting ring.

6. Apparatus as set forth in claim 3, which comprises spring means arranged to transmit a reciprocating movement of said plungers to said dies in both directions of said reciprocating movement.

7. Apparatus as set forth in claim 1, in which:

two of said swaging units are provided; and

said workpiece is adapted to move through said units along said feed paths of said units in succession.

8. Apparatus as set forth in claim 7, in which:

said feed paths of said two swaging units are longitudinally aligned;

a transmission is disposed between said two swaging units and comprises a plurality of spur gears forming a circular series which is centered on said feed paths;

adjacent ones of said spur gears mesh with each other; and

a motor is provided to drive one of said spur gears.

9. Apparatus as set forth in claim 8, in which:

each of said spur gears is operatively connected to one of said eccentric shafts; and

the eccentric shafts operatively connected to adjacent ones of said spur gears belong to different ones of said swaging units.

10. Apparatus as set forth in claim 8, in which said transmis' sion comprises idler gears operatively connecting said motor to said one spur gear.

Claims

1. Apparatus for a continuous swaging of rod-shaped workpieces, which comprises: at least one swaging unit defining a feed path along which a rod-shaped workpiece is axially movable through said unit, said unit comprising; a frame; a plurality of guides spaced around said path and extending substantially radially with respect to said path and rotatably mounted in said frame on axes which extend transversely to said path; a plurality of dies which consist of connecting rods and are slidably mounted in respective ones of said guides; a plurality of eccentric shafts mounted in said frame and extending parallel to said path and operatively connected to respective ones of said dies to reciprocate the same in said guides; and oscillating means for imparting to each of said dies an oscillating pivotal movement about the axis of rotation of the respective guide.

3. Apparatus as set forth in claim 1, in which said oscillating means comprise: a plurality of plungers, each of which is associated with and spaced from one of said guides and extends parallel to the associated eccentric shaft; reciprocating means for imparting to said plungers a reciprocating movement in response to the rotation of said eccentric shafts; each of said eccentric shafts carries an eccentric member; each of said dies comprises an elliptic chuck having two discs formed with respective grooves facing and crossing each other and a cylindrical spider, which is disposed between said discs and slidably engages said grooves and which embraces said eccentric member on the eccentric shaft associated therewith; and each of said plungers engages said spider of said die associated therewith.

4. Apparatus as set forth in claim 3, in which: each of said plungers engages the associated die so that a rotation of said plunger is prevented; said reciprocating means comprise; screw threads on each of said plungers; a plurality of nuts, each of which is threaded on one of said screw threads; a plurality of linkages, each of which consists of a crank arm connected to one of said nuts and a coupler connected to said crank arm; a plurality of elliptic chucks pivoted in said frame and comprising each a spider; a plurality of additional eccentric members mounted on respective ones of said eccentric shafts and embraced each by one of said spiders of said pivoted elliptic chucks; and said crank arm, coupler and pivoted elliptic chuck forming an articulated quadrangle.

5. Apparatus as set forth in claim 4, in which: an adjusting ring is mounted in said frame for rotation about said path; and said pivoted elliptic chucks are pivoted to said adjusting ring.

7. Apparatus as set forth in claim 1, in which: two of said swaging units are provided; and said workpiece is adapted to move through said units along said feed paths of said units in succession.

8. Apparatus as set forth in claim 7, in which: said feed paths of said two swaging units are longitudinally aligned; a transmission is disposed between said two swaging units and comprises a plurality of spur gears forming a circular series which is centered on said feed paths; adjacent ones of said spur gears mesh with each other; and a motor is provided to drive one of said spur gears.

9. Apparatus as set forth in claim 8, in which: each of said spur gears is operatively connected to one of said eccentric shafts; and the eccentric shafts operatively connected to adjacent ones of said spur gears belong to different ones of said swaging units.

10. Apparatus as set forth in claim 8, in which said transmission comprises idler gears operatively connecting said motor to said one spur gear.