US3703823A

US3703823A - Upsetting or forging machines

Info

Publication number: US3703823A
Application number: US51537A
Authority: US
Inventors: Geoffrey Wilson
Original assignee: B&S Massey Ltd
Current assignee: B&S Massey Ltd
Priority date: 1969-07-03
Filing date: 1970-07-01
Publication date: 1972-11-28
Anticipated expiration: 1989-11-28
Also published as: CH556201A; DE2033107A1; GB1224260A; HU163425B; CS153088B2; SU491231A3; CA924936A; JPS4940065B1; CH536666A; DE2033107B2; FR2050484B1; FR2050484A1; PL84716B1; AT302772B; DE2033107C3; SE397642B

Abstract

An upsetting or forging machine in which in a die set there is provided one die arranged to carry out a circular rocking motion about a point associated with the center of the die set, means being provided for adjusting the angularity of the axis of the rocking die in relation to the axis of the other die of the die set and a bearing means being provided to compensate for any changes in die dimensions due to heating and thus prevent seizing up of the dies.

Description

United States Patent 51 Nov. 28, 1972 Wilson [54] UPSE'ITING OR FORGING MACHINES [72] Inventor: Geoffrey Wilson, Denton, England [73] Assignee: B. 8: S. Massey Limited [22] Filed: July 1, 1970 [21] Appl. No.: 51,537

[30] Foreign Application Priority Data July 3, 1969 Great Britain ..33,5l1/69 [52] US. Cl ..72/406, 72/447 [51] Int. Cl. ..B21j 13/02 [58] Field of Search....72/67, 68, 115, 124, 429, 447, 72/406 [56] References Cited UNITED STATES PATENTS 1,148,065 7/1915 Warren ..72/67 1,455,266 5/ 1923 Rickenbach ..72/67 1,455,300 5/1923 Matthews ..72/67 3,173,281 3/1965 Bodmer ..72/67 3,440,850 4/1969 Friedrich .72/ 67 3,494,161 2/1970 Silichev ..72/ 67 FOREIGN PATENTS OR APPLICATIONS 2,060 9/ 1907 Great Britain ..72/67 Primary Examiner-Charles W. Lanham Assistant Examiner--Gene P. Crosby Attomey-Breitenfeld & Levine [57] ABSTRACT An upsetting or forging machine in which in a die set there is provided one die arranged to carry out a circular rocking motion about a point associated with the center of the die set, means being provided for adjusting' the angularity of the axis of the rocking die in relation to the axis of the other die of the die set and a bearing means being provided to compensate for any changes in die dimensions due to heating and thus prevent seizing up of the dies.

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UPSETTING OR FORGING MACHINES This invention concerns upsetting or forging machines.

Upsetting or forging machines are known in which there are two dies which are arranged to move relative to each other along a common axis so that the pressure exerted upon a workpiece is built up by the dies over the whole area of the workpiece simultaneously. In such machines the forces exerted are very high and thus the machines must be of heavy and extremely rigid construction to ensure that the upsetting or forging operation is carried out efficiently.

It has been proposed by the applicants to provide in an upsetting or forging machine a die system utilizing a pair of co-operating dies one of which is adapted to perform a circular rocking motion relative to the other about a center at or near the axial center line of the dies. Whilst such an arrangement provides for the ability to produce forgings using substantially lower operating forces between the dies than are used in machines of the kind referred to above when carrying out upsetting or forging operations the proposed machines have certain disadvantages which have led to machines of this kind not being universally acceptable. The reason for the ability to use substantially lower operating pressures lies in the fact that only a relatively small part of the workpiece is subjected to pressure at any instant in time.

In the proposed machine that die which is adapted to perform the circular rocking motion was arranged to be retained in a die carrier itself arranged to be retained in a main bearing support and its motion was to be derived from a drive shaft whose inclined axis moved around a center line of the lower die in a circular path.

In many cases, when the workpiece is worked upon heat transfer from the workpiece to the rocking die would cause expansion. Thus, in the'proposed arrangement, since there was no provision made for the effects of the expansion in either the rocking die or its carrier after a period of use the rocking die cover would have siezed up in its support. Using the proposed arrangement, even in the case of a cold forging operation heat generated due to friction between the bearing surfaces of the die carrier and its support and due to the action of upsetting or forging would be such that the machine could not be operated efficiently, particularly at high speed, due on the one hand basically to heat transfer from the workpiece in a hot forging operation or on the other hand to the heat generated at the bearing surfaces of the die carrier and its support during a cold forging operation.

Clearly if the proposed machine were used at a sufficiently low speed the frictionally generated heat could be dissipated to a large extent but the machine would be uneconomical due to its low rate of production.

The object of the present invention is to provide an upsetting or forging machine incorporating a die adapted to perform a circular rocking motion which thereby has the advantages of such an arrangement in so far at least as reduction of operating pressures by substantial amounts is concerned and additionally to provide means for compensating for the disadvantages of expansion outlined above thus allowing for continuous high speed operation and efficiency.

According to the present invention an upsetting or forging machine of the kind incorporating a die set adapted to have one die perform a circular rocking motion about a center at or near the center of the die is characterized in that, between a die carrier and its support member is provided a hearing or bearings adapted to compensate for dimensional changes in the die and carrier.

Preferably the die carrier is provided with at least two bearings each being capable of rocking about a pivot axis displaced from and at right angles to the central axis of the die.

Conveniently the carrier support is part spherical and is provided with at least two bearings each being capable of rocking about a pivot axis displaced from and at right angles to an axis of rotation of a drive shaft.

In a modified construction there is provided a die carrier mounted by means of bearings adapted to contain thrust loading at least, in a drive shaft extension, said drive shaft being mounted in bearings in a carrier support.

In a further modification there is provided a die support and carrier being interposed therebetween a bearing adapted to transmit drive from a drive shaft to the die carrier, said bearing and die carrier at least having co-operating conical faces.

The invention will now be described further, by way of example only, with reference to several practical forms thereof and the accompanying drawings in which:

FIG. 1 is a sectional elevation through one fonn of die and carrier arrangement adapted to enable a die to perform a circular rocking motion in accordance with the invention;

FIG. 1a is a perspective view of part of the arrangement of FIG. 1;

FIG. 2 is a view similar to FIG. 1 of a modification in the die supporting arrangement;

FIG. 3 is a diagrammatic view of a modification of the arrangement of FIG. 1;

FIG. 4 is a view similar to FIG. 3 of a further modification; and

FIG. 5 is a further view similar to FIG. 3 of a still further modification.

In the following description reference will be made in detail only to those parts of an upsetting or forging machine relating to the arrangements to provide the circular rocking motion in one die, the remaining parts of the machine being capable of being made in well known manner.

Referring first to FIG. 1 the die-mounting and drive arrangement comprises a massive housing 10 in which is mounted, in bearings 11 and 12, a drive shaft 13 is adapted to rotate about an axis 14 co-incident with the longitudinal axis of the shaft 13. The drive shaft 13 has at its end a drive pulley (or drive gear) 15 and this is secured to a flywheel 16 mounted on the shaft 13.

At the end of the drive shaft 13 remote from the pulley 15 is a drive shaft extension 17 of disc form, this latter having its center offset to the center of the drive shaft 13. Integral with the disc 17 is a stem 18 (which is also considered to be part of the drive shaft 13.) The stem 18 carries a combined radial and thrust bearing 19. The disc 17 has an angularly disposed face 20 remote from the drive shaft 13. The inner shell 21 of the bearing 19 is secured to the stem 18 and the outer shell 22 carries a yolk 23 having three arms 24 one only of which is shown, disposed at 120 intervals around the yolk 23.

Mounted in the housing is a support 25 of hemispherical form in which are three openings 26 at 120 spacing into which the free ends 27 of each arm 24 of the yolk 23 extend.

The arms 24 of the yolk 23 are bolted or otherwise firmly secured to a die carrier 28 which is of substantially hemispherical form and which, with a clearance of substantial size, fits within the support 25. The die carrier 28 is secured in practice to the end region 27 of the arms 24 and the yolk 23.

The die carrier 28 hasa recessed free face 29 to which can be removably secured a die 30 which in the illustrated form has an operative face which is conical in shape, but of course this form of die face is completely optional. The die is flanged as at 31 to facilitate its fixing by means of for example bolts 32, to the die carrier 28.

The die carrier 28 is so secured to the arms 24 of the yolk 23 as to have its axis 33 and the axis of the die 30, inclined at an angle to the axis 14 of the drive shaft 13. The two

axes

14 and 33 intersect at or near the center of the operative face of the die 30.

At 120 spacing around the periphery of the die carrier 28 and interspaced between the arms 24 of the yolk 23 are the centers of bearing pads 34 (one only of which is shown). The bearing pads are each of substantial size so that, with the exception of the areas of the carrier face occupied by the end region 27 of the arms 24 of the yolk 23, they overlie substantially the whole of the surface of the carrier 28.

Each bearing pad has a face 35 which conforms in shape to the shape of the support 25 and which cooperates with the face of the support 25 to mount the die carrier 28 in the hemispherical space defined by the support 25. More detailed reference to the contour of the face 35 of the pads 34 will be contained hereinafter.

At the opposite face of the bearing pads 34 and centrally thereof is a hemispherical protrusion 36 which seats within a block 37 set into and fixed to the die carrier 28. The block 37 has a hemispherical seating for the protrusion 36. A location strip 38 is located in the pad 34 and a recess 39 is machined into the die carrier 28.

The disc 17 and thus the die carrier 28 are urged towards the flywheel 16 by means of a series of packs of springs or belville washers B contained in recesses R in a flange F of a sleeve S surrounding the drive shaft 13 and contained in the housing 10. This sleeve S contains the bearings 11 and 12. The packs of springs or belville washers B surround a bolt which itself is secured to the housing 10 and which passes through the springs or belville washers B and thus they serve at all times to draw the die carrier 28 into the hemispherical support 25.

Mounted on the free face of the die carrier 28 is a gear ring 40 the teeth 41 of which are adapted successively to mesh with corresponding teeth 42 of a gear ring 43 mounted in a face plate 44 carried by the housing 10 of the machine.

Mounted around the inner periphery of the gear ring 43 is a deflector plate 45 which extends from the gear ring across the space in which the gear teeth of the

rings

40 and 43 are accommodated and into the space between the periphery of the die 30 and the lower region of the die carrier 28. This deflector plate serves to prevent scale from fouling the gear teeth and also to prevent lubricant from entering the area in which the die is, in use, operative.

Lubrication of the bearing 19 is via a series of lubricant passageways 46 in the drive shaft 13, the disc 17 and yolk 23. v

Lubrication of the bearing pads 34 and support 35 is via a lubricant supply passage 47 through the housing 10 and into the face of the support 35 between it and the bearing pads 34.

In one form of bearing pad lubrication the bearing pads are each provided with three recesses 48 between each of which is a land 49, the periphery of the pad is also provided with a land 49 so that three reservoirs 48 for lubricant are provided. There is a lubricant passage 47 for each reservoir and oil is arranged to be pumped to the reservoirs. The lubricant spilling over the lands to flow into a reservoir around the gear rings and back to tank. The perspective view of part of the face of one bearing pad (FIG. 1a) illustrates the form of the pad face 35. Alternatively the bearing may be of the hydrodynamic type. In this case the surface of the bearing pad will be plain and a series of spaced lubricant ports will be provided. The lubricant is pumped at constant pressure and the pad as it moves will only take up as much lubricant as is required to maintain its surface completely lubricated.

In operation the die is caused to perform a circular rocking motion without actual rotation about its axis in the following manner.

The drive shaft 13 is rotated at say 1,500 r.p.m. and thus the disc 17 and stem 18 rotates at the same speed about the axis 14. The bearing shell 21 also rotates at this speed and thus causes the axis 33 of the die 30, die carrier 28 and yolk 23 to move about the axis 14 but the die 30 merely rocks due to the provision of the two gear rings 40 and 43 so that a point in the die face will always remain in the same relative position to a corresponding point on a non-rocking die located below the rocking die which latter of course rocks at high speed towards and away from the non-rocking die thus to bring successive'points on the rocking die into contact with a workpiece in rapid progression. The workpiece is thus acted upon in such a manner that, with the die referred to flat face will be produced by the rocking die but of course the opposite face of the workpiece will be forged to correspond to the contour of the nonrocking die. Since there is no rotation of the rocking die the latter can have a more complex form than that referred to so that a forging having a complex contour on both faces can be produced.

Since only a relatively small area of the workpiece is subjected to pressure at any instant in time the operating force of the machine can be very substantially lower than would be the case if the whole of the workpiece were to be operated upon simultaneously.

having a drive pulley or gear 111 and flywheel 112 at one end. The drive shaft 110 is mounted in

bearings

113 and 114 and a housing 115 and at its end remote from the pulley or gear 111 is an extension 116 of split disc form. The split disc 116 comprises two parts 117, 1 18, the part 117 being integral with the drive shaft 110 and having (for a purpose explained below) an angular free face 119 against which a corresponding angular face 120 of the part 118 can seat. The reason for the provision of the angular faces 119,120 lies in the fact that it is desirable to be able to adjust the amount by which a die 121 can rock and thus clearly this requires the ability to adjust the angularity of the axis 122 of the die 121 relative to the axis of rotation 123 of the drive shaft 110. It follows that the relative rotation of the two parts 117 and 118 will enable such angularity of the axis 122 to axis 123 to be achieved and when so achieved it must be possible to lock the parts against further relative movement. To this end an arcuate slot is provided around part of the peripheral region of the part 117 and in this slot is located a locking bolt 124 which passes through a hole 125 in the part 118. By screwing the nut 126 tight on the bolt 124 when the parts 117, 118 have been adjusted to give the requisite angle of rocking further movement of the two parts 117, 118 is prevented.

Mounted indirectly in the part 118 is a die carrier 127 to which the die 121 can be attached. The die 121 in this case is flanged and a mounting ring 128 is provided. The ring 128 is stepped to overlie the flange of the die 121 and is adapted to be bolted to the carrier 127. To prevent rotation of the die 121 relative to the carrier 127 it is preferable to provide a square or other non-circular spigot 129 on the die 121 and to seat this in a recess of corresponding shape in the face 130 of the carrier 127.

The manner in which the die carrier 127 is indirectly mounted in the part 118 includes the provision of a stepped mounting spigot 131 upon each step of which is a radial and thrust bearing 132 having its inner shell mounted on the spigot 131 and its outer shell on the carrier I 18.

Gear rings I33 and 134 are provided to prevent rotation of the die 121 in addition to its designed rocking motion, these gear rings being respectively mounted on the die cover 127 and housing 115.

Lubricant passageways 135 are provided for supplying lubricant to the various bearings and bearing surfaces these passageways being formed in the housing 115 and in the split disc 116. A scale guard 136 is provided around the gear rings, in this case consisting of two parts one attached to each gear ring. Lubricant for the gear rings 133, 134 is contained between the guard 136 at one side of the rings and in wall 137 at the other side.

The schematic illustration of FIG. 3 represents a further modification in the construction and arrangement of parts for supporting a die in a manner such that circular rocking motion can be achieved. In this arrangement there is provided a drive shaft 210 adapted to be driven from a belt pulley or gearing (not shown). At the end of the shaft remote from the drive there is provided a support 211 adapted to be mounted in a housing (not shown). The support 211 has a conical inner face 212 which is disposed at 45 to the axis of the cone and through the apex of this cone passes an extension 213 of the drive shaft 210 (bearings would of course be provided for locating the drive shaft correctly). On the free end of the extension 213 is a conical bearing 214 the outer conical face 215 of which is provided with lubricant reservoirs 216. The inner conical face 217 of this bearing 214 has an axis 218 disposed angularly with respect to the axis 219 of the drive shaft 210 and the angle of the face 217 of this conical surface with respect to its axis 218 is also 45 Within the inner conical face 217 of the bearing 214 is a conical die carrier 220 adapted to receive a die 221. Lubricant reservoirs 222 are formed in the conical face 223 of the die carrier 220. The angle of 45 of the cone faces with respect to their axis is chosen to accommodate for expansion of the parts when in use and to ensure that this can move under expansion, without seizing, along the line of the cone faces.

As in the previous arrangements the die performs a rocking motion without rotation since the die carrier is provided with a gear ring the teeth of which mesh with the teeth of the second gear ring mounted on the housing of the machine (the gear rings are not shown).

In this arrangement if it is desired to enable the angular position of the die relative to the support to be varied the bearing would be split into two parts to enable relative movement of one part to the other to be achieved and of course a locking means would be provided to secure the two parts of the bearing at the desired position. A locking means such as that referred to in relation to FIG. 2 could be used.

If desired of course the lubricant reservoirs could all be formed on the bearing 214 or in fact one set of reservoirs could be provided on the support 211 and one on the die carrier 220 or alternatively one set could be provided on the bearing in relation to the die carrier 220 and the other on the bearing in relation to the support 21 1.

Again either hydrostatic or hydrodynamic lubrication could be used.

FIG. 4 shows a modification of the arrangement of FIG. 3 in which a support 223 is provided with a flat surface, in this case the bearing 224 has a corresponding flat face 225 (with suitable provision either in the bearing or the support for lubrication) and its inner face is conical to receive a die carrier 226 of the kind referred to in relation to FIG. 3. Again lubrication reservoirs 227 are provided either on the die support or the bearing surface as required.

Angular adjustment of the axis of the die carrier 226 in relation to the axis of the drive shaft is possible by providing a split bearing 224. Parts corresponding to those of FIG. 3 are given the same reference numerals as in FIG. 3.

FIG. 5 shows the relevant parts of a modification of the arrangement of FIG. 1 in a diagrammatic manner. In this case the support 325 is provided with blocks 337 adapted to receive the bearing pads 334. The die carrier is mounted by a yolk 323 having arms 324 at spacing and the bearing pads 334 are interspaced between the arms of the yolk.

Adjustment of the angularity of the die is achieved in the manner previously described.

In the arrangements of FIGS. 1 and 5 the bearing pads may have hemispherical recesses in place of the protrusions and the

blocks

37 and 337 are in this case provided with protrusions adapted to seat in the recesses.

It is also possible to provide a centrally disposed shaft on the die carrier 28 of FIGS. 1 and 5 to replace the yolk arrangement described if so desired. In this case the axis of the central shaft would be angularly disposed relative to the axis of the drive shaft.

Iclaim:

1. In an upsetting or forging machine, at least one die set, means associated with one die of said die set arranged to cause said one die to perform a circular rocking motion about a point related to the center of said die set, a die carrier for said one die adapted to carry out said circular rocking motion, a support member for said die carrier, and bearing means between said die carrier and said support member, said bearing means being so arranged as to compensate for dimensional changes in said die and said die carrier.

2. In an upsetting or forging machine as set forth in claim 1, said bearing means comprising at least two bearings, a pivot axis for each of said bearings, said pivot axis for each of said bearings being displaced from and at right angles to a central axis of said one die, said bearings being rockable about their respective pivot axes.

3. In an upsetting or forging machine as set forth in claim 1, said bearing means comprising at least two bearings, a pivot point for each of said bearings, a central axis for said one die, said pivot points being displaced from said central axis of said one die, said bearings each being universally movable about their respective pivot points.

4. In an upsetting or forging machine as set forth in claim 1 said support member being of part spherical form, at least two bearings for said one die, a pivot axis for each of saidbearings, a drive shaft, an axis of rotation for said drive shaft, said pivot axis for each of said bearings being displaced from and at right angles to said axis of rotation of said drive shaft.

5. In an upsetting or forging machine as set forth in claim 1, said support member being of part spherical form, at least two bearings for said one die, a pivot point for each of said bearings, a drive shaft, an axis of rotation for said drive shaft, said pivot points for said bearings being displaced from said axis of rotation of said drive shaft, said bearings each being universally movable about their respective pivot points.

6. In an upsetting or forging machine as set forth in claim 1 said die carrier being spaced from said support member, a drive shaft, and a bearing integral with said drive shaft and arranged to transmit drive to said die carrier.

7. In an upsetting or forging machine, at least one die set, means associated with one die of said die set arranged to cause said one die of said die set to perform a circular rocking motion about a point related to the center of said die set, a die carrier for said one die adapted to carry out said circular rocking motion, a drive shaft adapted to drive said die carrier a housing member, bearings in said housing member for mounting said drive shaft, a drive shaft extension on said drive shaft, and bearing means adapted to contain thrust loading at least in said drive shaft extension said die carrier being mounted on said drive shaft extension by means of said bearings contained in said drive shaft extension.

8. In an upsetting or forging machine as set forth in claim 7, said die carrier being spaced from said drive shaft extension, and said bearing means including radial and thrust bearings arranged to transmit motion from said drive shaft to said die carrier, said radial and thrust I bearings having rollers arranged with their peripheries disposed between a pair of frusto-conical surfaces, one said surface being carried by said drive shaft extension and the other said surface being carried by said die carrier.

9. In. an upsetting or forging machine as set forth in claim 7, an axis for said one die, an axis for said die carrier, and means for adjusting the angular relationship between said axis for said one die and said axis for said die carrier.

10. In an upsetting or forging machine as set forth in claim 9 inclined faces on said drive shaft extension, and means to lock said drive shaft at any pre-determined angular relationship of said axis for said one die and said axis for said die carrier.

11. In extension, upsetting or forging machine at least one die set, means associated with one die of said die set arranged to cause said one die of said die set to perform a circular rocking motion about a point related to the center of said die set, a die carrier for said one die adapted to carry out said circular rocking motion, a drive shaft adapted to drive said die carrier, an axis for said one die, an axis for said drive shaft a two part drive shaft extension on said drive shaft, bearing means between said die carrier and said drive shaft extension naturally inclined co-operating faces on each part of said two part drive shaft extension, means relatively to rotate said two parts of said two part drive shaft extension thereby to adjust said angular relationship between said axis for said one die and said axis for said drive shaft and means to lock said two parts of said two part drive shaft extension at any pre-determined position thereby to maintain any adjusted angular relationship between said axis of said one die and said axis of said drive shaft.

12. In an upsetting or forging machine as set forth in claim 11 a die support, a carrier member spaced from said die support, a bearing of conical form between said die support and said carrier member, said bearing of conical form having one shell part secured to part of said two part drive shaft extension, an inclined face on one part of said two part drive shaft extension and a cooperating inclined face on the other part of said two part drive shaft extension.

13. In an upsetting or forging machine at least one die set, means associated with one die of said die set arranged to cause said one die of said die set to perform a circular rocking motion about a point related to the center of said die set, a die carrier for said one die adapted to carry out said circular rocking motion, a yolk carrying said die carrier, a drive shaft attached to said yolk, at least two arms on said yolk extending around said die carrier, connections between said die carrier and the arms of said yolk, bearing pads on said die carrier, said arms of said yolk being positioned between said bearing pads of said die carrier.

14. In an upsetting or forging machine at least one die set, means associated with one die of said die set arranged to cause said one die of said die set to perform a circular rocking motion about a point related to the center of said die set, a die carrier for said one die adapted to perform said circular rocking motion, an anll. fixed gear ring, teeth on said annular gear on said die carrier and teeth on said fixed gear ring intermeshing successively when said die carrier is carrying out said circular rocking motion thereby to prevent rotation of m gear on Said die carrier periphery, a fi d gear said die carrier during said circular rocking motion.

Claims

4. In an upsetting or forging machine as set forth in claim 1 said support member being of part spherical form, at least two bearings for said one die, a pivot axis for each of said bearings, a drive shaft, an axis of rotation for said drive shaft, said pivot axis for each of said bearings being displaced from and at right angles to said axis of rotation of said drive shaft.

8. In an upsetting or forging machine as set forth in claim 7, said die carrier being spaced from said drive shaft extension, and said bearing means including radial and thrust bearings arranged to transmit motion from said drive shaft to said die carrier, said radial and thrust bearings having rollers arranged with their peripheries disposed between a pair of frusto-conical surfaces, one said surface being carried by said drive shaft extension and the other said surface being carried by said die carrier.

9. In an upsetting or forging machine as set forth in claim 7, an axis for said one die, an axis for said die carrier, and means for adjusting the angular relationship between said axis for said one die and said axis for said die carrier.

14. In an upsetting or forging machine at least one die set, means associated with one die of said die set arranged to cause said one die of said die set to perform a circular rocking motion about a point related to the center of said die set, a die carrier for said one die adapted to perform said circular rocking motion, an annular gear on said die carrier periphery, a fixed gear ring, a stationary part of said machine carrying said fixed gear ring, teeth on said annular gear on said die carrieR and teeth on said fixed gear ring intermeshing successively when said die carrier is carrying out said circular rocking motion thereby to prevent rotation of said die carrier during said circular rocking motion.