US3197994A

US3197994A - Four-column press

Info

Publication number: US3197994A
Application number: US230775A
Authority: US
Inventors: Samuel Herbert John; Rosenthal Salli Alfred
Original assignee: Loewy Engineering Co Ltd
Current assignee: Loewy Engineering Co Ltd
Priority date: 1962-06-21
Filing date: 1962-06-21
Publication date: 1965-08-03
Anticipated expiration: 1982-08-03

Description

Aug. 3, 1965 H. J. SAMUEL ETAL FOUR-COLUMN PRESS '7 Sheets-Sheet 1 Filed June 21, 1962 E NE a R a a .3 mm Mm wk Inventors SALLI ALFRED ROSENTHAL HERBERT JOHN SA U Aug. 3, 1965 H. J. SAMUEL ETAL FOUR-COLUMN PRESS 7 Sheets-Sheet 2 Filed June 21, 1962 L A H "mm w mm... m f mm m #L UMB .m iiil ihwnhnflfiflflfltw W n .7 Q. w. G mw IQ I... .L R R Q E w h mllll d @E g Q & 9% E Q 5 i s QM a 3N N5 9 R x m. 55 w 3 I Q Q 3 m l I 75 1 H 1 1965 H. J. SAMUEL ETAL 3,197,994

FOUR-COLUMN PRESS Filed June 21, 1962 '7 Sheets-Sheet 3 Inventors SALLI ALFRED ROSENTHAL HERBERT JOHN .SAMU L Aug. 3, 1965 H. J. SAMUEL ETAL 3,197,994

FOUR-COLUMN PRESS Filed June 21, 1962 7 Sheets-Sheet 4 Inventors SALLI ALFRED ROSENTHAL HERBERT JOHN AM L tor ys Aug. 3, 1965 H. J. SAMUEL ETAL FOUR-COLUMN PRESS 7 Sheets-Sheet 5 Filed June 21, 1962 Inventors SALLI AL FRED ROSENTHAL FOUR-COLUMN PRES S 7 Sheets-Sheet 6 Filed June 21, 1962 lnvenlorfi SA LLI A LF'RED ROSENTHAL HERBERT JOHN l0 ys Aug. 3, 1965 H. J. SAMUEL ETAL 3,197,994

FOUR-COLUMN PRESS Filed June 21, 1962 '7 Sheets-Sheet 7 Inventors SALLI ALFRED ROSENTHAL HERBERT JOH SAMU L By w 3A 04w United States Patent 3,197,994 FOUR-CGLUMN PRESS Herbert John Samuel, Northbourne, Dorset, and Salli Alfred Rosenthal, Poole, Dorset, England, assignors to The Loewy Engineering Company Limited, Bournemouth, England, a corporation of Great Britain Filed June 21, 1962, Ser. No. 230,775 8 Claims. (Cl. 72-263) This invention relates to presses, in particular hydraulic presses, in which two massive platens are connected'to each other by four columns which take the reaction of the press power, one platen supporting, for example,

a hydraulic main working cylinder and the other platen supporting a holder for a workpiece. The conventional arrangement of these four columns is one in which they are equidistant from the working axis of the press, i.e., the axis in which the press power acts. The axes of the columns are then situated at the corners of a rectangle through whose centre the main workingaxis of the press passes.

In four column hydraulic presses having the conventional arrangement of columns, the distance of their columns from the main working axis, and thereby also the overall dimensions of the platens of'the press, is determined by the size and the number of the main working cylinders, so that in large presses having a high capacity of press power this distance can become considerable. This is for instance the case with metal extrusion presses or forging presses, including piercing presses.

In these lastmentioned presses the workpieces are received in a container from which they are pressed out through a die which gives them the desired shape, or in which they remain during the pressing operation, to be shaped in accordance with the configuration of the workpiece container itself. I

In is an object of the present invention to provide a four-column press in which the columns are arranged in a novel and advantageous manner with regard to the working axis of the press.

According to the invention there is provided a press having four tension columns which connect the two platens of the press to each other, wherein the columns are arranged, so that, in transverse section, the axes of the columns define the corners of a parallelogram with diagonals of unequal length, the working axis of the press passing through the point of intersection of the diagonals. The diagonals of the parallelogram defined by the columns are preferably perpendicular to one another but alternatively the columns may if desired be arranged so that their diagonals form an acute angle with each other.

A parallelogram defined by the four columns of a press according to the invention can have a smaller area than the rectangle defined by the four columns of a press of the conventional type and of the same capacity. In this way, the overall dimensions of the platens of the press can be reduced and the press made lighter and more compact without impairing its strengthor rigidity. This reduction in the overall dimensions can be achieved without interfenence with the arrangement of any auxiliary cylinders of the press, such as return cylinders or cylinders for the shifting of the container, as there will be sufficient space for the accommodation of these auxiliary cylinders on the sides of the parallelogram defined by the tour press columns.

A special case in which the invention can be applied with advantage is that of a press having three main working cylinders, which are so arranged that their axes are in a common plane passing through the working axis of the press. The middle one of the three cylinders may be then arranged co-axially with the main working 3,197,994 Patented Aug. 3, 1965 axis and the two side cylinders on or near two opposing sides of the parallelogram defined by the four columns. In this way, a compact arrangement of the cylinders and columns is obtained.

The invention is applicable both to horizontal and vertical presses. In the case of a horizontal press it may be preferable to arrange the columns so that each column is spaced from the horizontal plane through the working axis of the press. In this way the access to the working zone of the press and in particular to any tools in the workingaxis is unobstructed.

In the press according to the invention two of its columns are closer to the Working axis of thepress than the others, and the former will therefore receive a greater share of the'total load. This may be taken into account by making the columns which are closer to the working axis of the press of larger cross-section than the others, or by making them of higher-grade material, or both. Unequal stretching of the columns due to their receiving different shares of the load may be prevented by prestressing one pair of the columns more than the other.

For the purpose of increasing the production of presses it has been proposed to provide them with a plurality of containers and/or with a plurality of dies which can be moved in succession from one or more outside stations into the working axis of the press, so that one of the containers or dies could be made ready for a pressing operation whilst pressing was in progress at another. The containers and dies were mounted on carriers, separate carriers being provided in respect of the containers and dies.

In some of these presses, the carriers are rotatably mounted about one of the columns of the press. The

diameter of the carrier is then determined by the distance between the axis of the associated column and the working axis of the press. This results, particularly in large presses having all the columns equidistant from the working axis of the press, in carriers which are very heavy and have a correspondingly great moment of inertia. The acceleration and deceleration of such carriers during their rotary movement requires the application of considerable force, and it is further diflicult, in the short time available between subsequent pressing operations, to bring the carriers to a standstill exactly in the position in which one of the containers or dies is in alignment with the working axis of the press, which is a necessity for the trouble-free operation of the press.

The novel arrangement of the columns of the press of the present invention is particularly advantageous when the press is provide with a rotary container-carrier or die-carrier; since the carrier may be mounted on one of the columns situatedon the shoter of the two diagonals of the parallelogram defined by the four columns. In this way the axis of rotation of the carrier is a shorter distance from the working axis of the press than in conventional presses in which the four columns are equidistant from the working axis, with the result that in a press according to the present invention, a rotary multi-die or multi-container carrier can be of smaller diameter and therefore have less weight and a reduced amount of inertia, as compared with a carrier on a conventional press of the same capacity.

When applying the invention to a four-column press with two separate rotary carriers, one for the containers and for the dies, one of the carriers may be rotatably mounted on one of the two columns on the shorter diagonal of the parallelogram defined by the columns and the other carrier on the other column on the same di agonal.

An embodiment of the invention will now be described,

3 by way of example, with reference to the accompanying drawings in which:

FIG. 1 is an elevation view of a horizontal metal extrusion press constructed according to the invention.

FIG. 2 is a sectional elevation through the working axis of the press.

FIG. 3 is part-sectional plan view of the press.

FIG. 4 is a sectional view of the press, taken along the line IVIV of FIG. 1.

FIG. 5 is a sectional view of the press, taken along the line V-V of FIG. 1.

FIG. 6 is a sectional view of the press, taken along the line VI-VI of FIG. 1.

FIG. 7 is a view along the line VIIVII of FIG. 1.

a FIG. 8 is a section view corresponding to that of FIG. 4, of a modified form of the press. The press shown in the drawings is specifically designed for the extrusion of tubes from metal billets, although the press is adaptable for other forms of extrusion, such as, for example, the extrusion of solid rods. The press comprises front and rear platens 10, 11 mounted on a base 12 and rigidly interconnected by four

tension columns

13, 14, 15, 16 firmly rooted at their ends in the platens, a die-carrier 17 carrying two dies 18 and 18', the carrier 17 being axially movable towards and away from the adjacent front platen and angularly movable to align each of the dies 18 and 18' in succession with a bolster 19 mounted on the front platen 10, a container-carrier 21) carrying two containers 21 and 21', the carrier being axially movable towards and away from the die-carrier 17 and angularly movable to register each of the containers in succession with one of the dies aligned with the bolster, a sealing head 22 for moving the carrier 20 to engage one of the containers 21 against one of the dies 18 or 18' aligned with the bolster 19, a main ram 23 carrying at the front end thereof an extrusion stem 24 aligned with the bolster 19, four main

hydaulic cylinders

25, 26, 27, 28 mounted in the rear platen 11, the

cylinders

25, 26, 27, 28 having

pistons

29, 30, 31, 32 secured at their front ends to the main ram 23, a cylindrical mandrel 33 and a mandrel holder 34 extending co-axially through the stem 24 and ram 23-, and a mandrel-operating hydraulic cylinder 35 connected to the rear platen 11.

As shown in FIG. 4, the four

columns

13,14, 15, 16 are arranged, so that, in transverse section, the axes of the columns define the corners of a parallelogram a, b, c, d having the diagonals a, c and b, d perpendicular to one another and at an angle to the horizontal, and the two opposing sides a, d and b, c lying in vertical planes. the

columns

13, 15 are arranged at the upper and lower ends respectively of the longer diagonal a, c and the

columns

14, 16 are arranged at the upper andlower ends respectively of the shorter diagonal b, d. The two platens 10, 11 have a configuration which corresponds approximately to that of the parallelogram defined by the four columns, though on a larger scale to encompass the parts of the columns rooted in the platens. The

centre. line through the point of intersection e of the diagonals a, c and b, d is the working axis XX (FIGS.

2 and 3) of the press, and the bolster 19 and front platen 10 are formed with central apertures 36, 37 respectively for discharge of tube extruded through a die 18. It will be noted from FIG. 4 that each of the

columns

13, 14,

are disposed symmetrically above and below the centre line of the press, that is the line through the point of intersection e of the diagonals a, c and b, d, the cylinder being arranged with its axis in the plane through the corners a, b of the parallelogram defined by the four 4 columns (see FIG. 7) and the cylinder 26 being arranged with its axis in the plane through the corners c, d of the parallelogram. The main hydraulic cylinders 27, 28 are disposed symmetrically one on each side of the centre line of the press, the cylinder 27 being arranged with its axis in the plane through the corners b, c of the parallelogram and the cylinder 28 being arranged with its axis in the plane through the corners a, d of the parallelogram. The

cylinders

25, 26, 27, 28 are firmly rooted in apertures in the rear platen 11, and their

pistons

29, 319, 51, 32 are firmly secured at their front ends to a crosshead 38 on the ram 23. The

cylinders

25, 26, are of equal diameter and, in operation, are supplied simultaneously with liquid at equal pressures, so that the resultant of the thrust transmitted to the ram 23 through the pistons 29, 3%) acts along the centre line of the press. The cylinders 27, 28 are of equal diameter and, in operation, are supplied simultaneously with liquid at equal pressures, so that the resultant of the thrust transmitted to the ram 23 through the pisons 31, 32 acts along the centre line of the press. The centre line of the press is thus the working axis XX of the press. Liquid under pressure may be supplied simultaneously to all the

cylinders

25, 26, 27, 28, or selectively to one or other of the two pairs of

cylinders

25, 26 and 27, 28 whereby variations in thrust may be exerted in the ram 23.

The main ram 23 comprises a cylindrical front portion 43 containing known means (not shown) rigidly securing the extrusion stem 24 to the front end of the ram, a crosshead 44 adjacent to the front portion 43, a cylindrical intermediate portion 45 between the crosshead 44 and the crosshead 33 secured to the pistons 29, 5t 51, 32, the intermediate portion 45 having side windows 46 for a purpose to be described hereafter, and a cylindrical rear portion 47 slidably mounted in a bearing 43 secured in a central aperture in the rear platen 11, the stem 24 and the front, intermediate and

rear portions

43, 45, 47 being co-axial with the working axis XX of the press. The front crosshead 44 is provided at its ends with two downwardly projecting lugs 49 fitted at their lower ends with shoes 50 in sliding engagement one with each of two outwardly inclined tracks 51 on support blocks 52 mounted on the base 12, and the bottom of the crosshead 33 is provided with a bracket 53 fitted with a shoe 54 in sliding engagement with a track 56 mounted on the base 12, the

shoes

50 and 54 supporting theweight of the main ram 23.

The mandrel 33 is slidably mounted in a central bore in the extrusion stem 24 and the mandrel holder 34, which is attached to the rear end of the mandrel 33, is slidably mounted in a central bore in the main ram 23 and extends beyond the rear of the main ram. The rear end portion of the mandrel holder 34 is of enlarged diameter and forms the piston 60 of the hydraulic cylinder 35 which is fixedly mounted on a yoke 61 secured by two rods 62. to the rear platen 11. The part of the mandrel holder 34 within the intermediate portion 45 of the ram 23 extends through an aperture in a crosshead 63 and is secured thereto by nuts. The crosshead 63 projects through the windows 46 in the ram and two hydraulic cylinders 64, are fixedly secured in apertures in the ends of the crosshead 63, the cylinders 64 being arranged symmetrically and on each side of the mandrel holder 34. The cylinders 64, 65 are slidably mounted on pistons 66, 67 respectively fixed at their front ends to the crosshead 44 on the ram 23. The mandrel holder 34, together with the mandrel 53, is movable forwards relative to the ram 23 by liquid fed under pressure to the cylinder 35 and the mandrel is movable rearwards relative to the ram 23 by liquid fed under pressure to the cylinders 64, 65. At the forward limit of travel of the mandrel holder 34 relative to the ram, the piston 61? at the rear end of the mandrel holder engages the rear end of the ram 23, and the thrust exerted on the ram by liquid under pressure in the

cylinders

25, 26, 27, 23 may be supplemented by an additional thrust exerted by the piston 60 on the rear end of the ram due to liquid under pressure in the cylinders 35. The cylinder and yoke 61 are supported on pedestals 59 on the base 12.

The sealing head 22 is supported on two bearings 60 (FIG. 6) which are slidably mounted on the two

columns

14, 16 on the shorter diagonal b, a of the parallelogram defined by the four columns, the bearings 69 being fixed in lugs '70 on the periphery of the sealing head 22. The sealing head 22 is provided with a central bore 71 for the passage of the front end of the ram 23, and the front end of the sealing head forms an abutment surface adapted to engage the rear end of a

container

21 or 21 aligned along the working axis XX of the press. The walls of the sealing head enclose an annular space 72 which is fed with cooling water by means not shown.

A hydraulic cylinder 74 is rigidly secured in an aperture in an auxiliary frame 75 mounted on bearings 76 on the columns 13, 14 (only one bearing 76 being visible in FIG. 6) and a hydraulic cylinder 77 is rigidly secured in an aperture in a further auxiliary frame 78 mounted on bearings 79 on the columns 15, 16 (only one bearing 79 being visible in FIG. 6), the two

cylinders

74, 77 being arranged symmetrically above and below the working axis of the press. The two

frames

75, 78 are in addition mounted on supports 00, 81 respectively on the base 12, the

supports

80, 81 bearing part of the weight of the two frames. The

bearings

76, 79 permit slight axial extension of the columns when under tension. A piston 82 is mounted in the cylinder 74 and secured at its front end to the upper portion of the sealing head 22, and a piston 83 is mounted in the cylinder 77 and secured at its front end to the lower portion of the sealing head 22. The cylinder 74 is secured to the front end of a cylindrical plunger 84 which is slidable-in a cylinder 85 formed in the piston 29, and the cylinder 77 is secured to the front end of a cylindrical plunger 86 which is slidable in a cylinder 87 formed in the piston 30, the two

plungers

84, 86 extending through cooperating apertures in the crosshead 38 on the ram 23.

Inorder to effect sealing of a container against a die, liquid under pressure is fed to all the cylinders 74, '77, 85, $7. The liquid in

cylinders

74, 77 forces the sealing head 22 against a container which is thus in turn forced against a die, and the reactive forces acting on the cylinders '74, 77 due to the pressure of liquid therein is resisted by the thrust acting on

theplungers

84, 86 due to the pressure of liquid in cylinders 35, 87. The cylinders 85, 37 are fed with liquid from a pressure accumulator (not shown) to permit infiow or discharge of liquid from the cylinders 85, 37 under pressure upon advance or retraction of the

pistons

29, 30 which are coupled to the main ram 23. The auxiliary frame 75 also serves as a guide for the main ram 23, the top of the intermediate portion 45 of the ram 23 having a longitudinal tongue 88 engaged in a groove on the underside of the frame 75.

The container carrier 20 is supported on a bearing 99 (FIG. 5) mounted on the column 16 on the shorter diagonal b, d of the parallelogram defined by the four columns, and the carrier 20 is both axially and rotatably movable on the column 16. The carrier 20 comprises a substantially rectangular block 91 having two locating arms 92 and 92' projecting one from each side of the block 91, the bearing being secured in a central transverse aperture in the block 91. The

billet containers

21 and 21 are mounted in apertures at opposite ends of the block 91, each container 21 and 21' being of a length such that the ends of the container project from the front and rear surfaces of the block 91, and each

arm

92 and 92 is formed with an aperture 93 and 93' of a diameter to permit passage of the extrusion stem 24, the axes of the

containers

21 and 21 and the apertures 93 and 93' being located on a circle centred on the axis of the column 16 and passing through the working axis of the press.

The carrier is drivably connected to a motor 94 (FIGS.

1, 3) on the front platen 10, a pinion 95 on the motor drive shaft is in mesh with a gear 96 secured to the front end of a shaft 97 which extends through a bore in the front platen 10, and a pinion 98 secured on the rear end of the shaft 97 is in mesh with a ring gear 99 surrounding the column 16 and secured to the hub of the carrier 20, the ring gear 99 being of a length such thatthe pinion 98 remains in mesh therewith over the axial range of movement of the carrier 20towards and away from the die-carrier 17.

The motor 94 is adapted to drive the carrier 20 in a clockwise direction, as viewed in FIG. 5, to align each

container

21 and 21 and

apertures

93 and 93 in succession with the working axis of the press. The leading surface of each end of the block 91 and the leading surface of the outer end of each arm 92 and 9- is formed with an

abutment surface

100, 100', 100" and 100", respectively, arranged to engage a locking member 101, and the trailing surface of each endof the block 91 and the trailing surface of the outer end of each arm 92 and 92' is formed with an

abutment surface

102, 102, 102", and 102', respectively, arranged to engage a locking member 103.

The locking

members

101, 103 are mounted in

housings

104, 105 respectively supported on the base 12, and the locking

members

101, 103 are retractable out of the path of movement of the abutment surfaces 100, 100', 100", 100', 192, 102', 102", 102" by electric solenoids. The abutment surfaces associated with each

container

21 and 21 or

aperture

93 and 93 are arranged, when engaged with the locking members, to lock the carrier 20 in a position in which the succeeding aperture 93 or 93' or container 21 or 21' respectively, is aligned with the working axis of the press. In order to align a container 21 or 21' or

aperture

93 or 93 with the working axis, the locking

members

101, 103 are retracted and the carrier 20 is rotated in a clockwise direction until the

opposite container

21 or 21 or

aperture

93 or 93 has moved past the locking

members

101, 103. The locking member 101 is then extending into the path of movement of the succeeding

abutment surface

100, 100', 100" or 100" and stops the carrier in a position in which the desired

container

21 or 21 or aperture 93 or 93' is aligned with the working axis. The locking member 103 is then extended to engage the opposing abutment surface 102 and thereby lock the carrier against rotational movement. Each abutment surface 102 is inclined outwardly towards the opposing abutment surface 100, and the locking member 103, when in engagement with an abutment surface 102, is urged outwards with a force sufficient to hold the carrier 20 against the locking member 101 and thereby ac curately locate the carrier in position.

Axial movement of the container carrier 20 away from the die-carrier 17, is effected by two push rods 106 (FIG. 2) arranged symmetrically above and below the working axis of the press and mounted in bearings 107 on the rear wall of the front platen 10. The front ends of the push rods 106 are secured to hydraulic cylinders 108 slidably mounted on plungers 109, the front ends of which are mounted on yokes 110 secured by two rods 111 to the front platen 10. Supply of liquid under pressure to the cylinders108 forces the latter rearwards and, upon engagement of the push rods 106 against the container carrier 20, forces the carrier 20 away from the die-carrier 17. The cylinders 108 are of a length such that, in their forward limit positions, the push rods 106 are Withdrawn to the front of the die-carrier 17.

The die-carrier 17 is supported on a bearing 112 (FIGS. 4, 5) mounted on the column 14 on the shorter diagonal 12,.d of the parallelogram defined by the four columns, and the carrier 17 is both axially and rotatably movable on the column 14. The carrier 17 comprises a hub 113 formed with four outwardly projecting

arms

114, 114', 114" and 114" arranged symmetrically around the hub,

' the bearing 112 being secured in the hub 113. Two die holders 115 and 115' fitted with dies 18 and 18' are mounted in apertures in the two opposing

arms

114 and 114" and the other two arms 114 and 114' are each formed with an

aperture

116 and 116 of a diameter to permit passage of the extrusion stem 24, the axes of the dies 18 and 18' and the apertures 116 and 116' being located on a circle centered on the axis of the column 14 and passing through the working axis of the press.

. The carrier 17 is drivably connected to a motor 117 (FIGS. 2, 3) mounted on the front platen 10. A pinion 1219 on the'drive shaft of the motor 117 is in mesh with a gear 119 secured on the front end of a shaft 118 which extends through a bore in the front platen 1t and a pinion 121 secured on the rear end of the shaft 118 is in mesh with a ring gear 122 surrounding the column 14 and secured to the hub 113, the ring gear 122 being of a length such that the pinion 1Z1 remains in mesh therewith over the axial range of movement of the die carrier 17 towards and away from thebolster 19.

The motor 117 is adapted to drive the die carrier 17 in a clockwise direction as viewed in FIG 4, to align each die 18 and 1S and aperture 116 and 116' in succession with the working axis of the press. The leading surface of the outer end of each

arm

114, 114', 114" and 114" is provided with an

abutment surface

123, 123, 123" and 123', respectively, arranged to engage a locking memher 124' and the trailing surface of the outer end of each

arm

114, 114', 114" and 114" is provided with an

abutment surface

125, 125, 125" and 125', respectively, arranged to engage a locking member 126. The locking

members

124, 126 co-operate with the abutment surfaces 123, 123, 123", 123", 125, 12 on each arm to align the dies 18 and 13' or apertures 116 and 116' in a succeeding arm along theworking axis of the press in a similar mannor to locking

members

101, 103 for the container carrier 2t) hereinbefore described in detail.

For clarity, the hydraulic connections for the hydraulic cylinders have not been shown in FIGS. 1-7.

In the press of FIGS. 1-7 each of the columns is spaced from the horizontal plane through the Working axis of the press. The four columns may however be arranged with the columns on the shorter diagonal lying in the horizontal plane through the working axis of the press. In the modified arrangement of FIG. .8 each of the two platens are interconnected by four

tension columns

130, 131, 132, 133 arranged at the corners of a parallelogram f, g, h, 1' having the longer diagonal f, h lying in a vertical plane and the shorter diagonal g, i in a horizontal plane, The die carrier 17 and the container carrier 20 are mounted on the

columns

131, 133 respectively on the shorter diagonal g, i, and the push rods 106 for effecting axial movement of the carrier 26 are located on the longer diagonal f, h. The main

hydraulic cylinders

25, 26 are preferably arranged with their axes lying centrally on the sides 1, g and h, i respectively, and the main hydraulic cylinders 27, 28 with their axes lying on the sides g, h and i, 1 respectively. While we have shown two non-rectangular parallelogram arrangements of the columns of a fourcolumn press, it will be understood that, as set forth in he objects of this specification, other non-rectangular parallelogram arrangements of the columns may be used and that other modifications may be made from the press as shown without departing from the spirit of our invention or the scope of the following claims.

We claim:

, 1. A press comprising a main frame consisting of two pressure platens and four horizontal tension columns on which the two platens are mounted in parallel spaced relation to each other, each of said columns extending from one platen to the other and each column being secured to both platens, the columns being arranged so that, in transverse section, the axes of the columns define the corners of a parallelogram having diagonals of unequal length, main hydraulic reciprocating means and a ram driven thereby, said reciprocating means being mounted on one of said platens'so that the said ram is movable towards the other of the said platens upon operation of the reciprocating means, the axis of the ram being aligned with the point of intersection of the said diagonals and constituting the working axis of the press, and the columns being arranged so that each column is spaced from the horizontal plane through the working axis of the press.

2. A press as set forth in claim 1 wherein the columns are arranged so that the diagonals of the parallelogram defined by the axes of the columns are perpendicular to one another.

3. A press comprising a main frame consisting of two pressure platens and four tension columns on which the two platens are mounted in parallel spaced relation to each other, the columns being arranged so that, in transverse section, the axes of the columns define the corners of a parallelogram having diagonals of unequal length, main hydraulic reciprocating means, a ram driven thereby, said reciprocating means being mounted on one of said platens so that the said ram is movable towards the other of the said platens upon operation of the reciprocating means, the axis of the ram being aligned with the point of intersection of the said diagonals and constituting the working axis of the press, and a carrier adapted to support a tool, the said carrier being mounted on one of the columns situated on the shorter of the two diagonals of the parallelogram and being angularly movable about the said one column between a position in which a tool on the carrier is aligned with the working axis of the press and a further position in which the tool is spaced from the working axis of the press.

4. A press suitable for the extrusion of a metal billet through a die, said press comprising a main frame consisting of two pressure platens and four tension columns on which the two platens are mounted in parallel spaced relation to each other, the columns being arranged so that, in transverse section, the axes of the columns define the corners of a parallelogram having diagonals of unequal length, main hydraulic reciprocating means and a ram driven thereby, said reciprocating means being mounted on one of said platens so that the said ram is movable towards the other of the said platens upon operation of the reciprocating means, the axisof the ram being aligned with the point of intersection of the said diagonals and constituting the working axis of the press, a container carrier supporting a container for the reception of the billet, and ,a die carrier for supporting the die, the said carriers being mounted one on each of the two columns situated on the shorter of the two diagonals of the parallelogram, each carrier being angularly movable about the associated column between a position in which the container or die is aligned with the working axis of the press and a further position in which the container or die is spaced from the working axis of the press.

5. A press suitable for the extrusion of a metal billet through a die, said press comprising a main frame consisting of two pressure platens and four horizontal tension columns on which the two platens are mounted in parallel spaced relation to each other, the columns being arranged so that, in transverse section, the axes of the columns define the corners of a parallelogram having diagonals of unequal length and perpendicular to one another, four main hydraulic piston and cylinder units mounted on one of said platens, the four units being arranged with their axes disposed one on each of the four sides of the parallelogram, a ram coupled to said units and movable towards the other of said platens upon operation of the hydraulic units, the axis of the ram being aligned with the point of intersection of the said diagonals and constituting the working axis of the press, and the columns being arranged so that each column is spaced from the horizontal plane through the working axis of the press, a container carrier supporting a container for the reception of the billet, a die carrier for supporting the die, the

said carriers being mounted one on each of the two columns situated on the shorter of the two diagonal-s of the parallelogram and each carrier being angularly movable about the associated column between a position in which the container or die is aligned with the working axis of the press and a further position in which the container or die is spaced from the working axis of the press, and each carrier being axially movable on the associated column to permit adjustment of the spacings between the die, the container and the other of said platens.

6. A press comprising a main frame consisting of two pressure platens and four tension columns on which the two platens are mounted in parallel spaced relation to each' other, the columns being arranged so that, in transverse section, the axes of the columns define the corners of a parallelogram having diagonals of unequal length, main hydraulic reciprocating means, a ram driven thereby, said reciprocating means being mounted on one of 1 said platens so that the said ram is movable towards the other of the said platens upon operation of the reciprocating means, the axis of the ram being aligned with the point of intersection of the said diagonals and con stituting the working axis of the press, and a carrier adapted to support a workpiece, the said carrier being mounted on one of the columns situated on the shorter of the two diagonals of the parallelogram and being angularly movable about the said one column between a position in which a workpiece on the carrier is aligned with the working axis of the press and a further position in which the workpiece is spaced from the working axis of the press.

7. A press comprising a main frame consisting of two pressure platens and four horizontal tension columns on which the two platens are mounted in parallel spaced relation to each other, each of said columns extending from one platen to the other and each column being secured to both platens, the columns being arranged so that, in transverse section, the axes of the columns define the corners of a parallelogram having diagonals of unequal length, two main hydraulic piston and cylinder units mounted on one of said platens, the two units being arranged with their axe-s disposed one on each of two opposing sides of the parallelogram, each unit being said diagonals and constituting the working axis of the press, and the columns being arranged so that each column is spaced from the horizontal plane through the working axis of the press.

8. A press comprising a main frame consisting of two pressure platens and four horizontal tension columns on which the two platens are mounted in parallel spaced relation to each other, each of said columns extending from one platen to the other and each column being secured to both platens, the columns being arranged so that, in transverse section, the axes of the columns define the corners of a parallelogram having diagonals of unequal length and perpendicular to one another, four main hydraulic cylinders mounted on one of said platens, the four cylinders being arranged with their axes disposed one on each of the four sides of the said parallelogram, four pistons disposed one in each of the said cylinders, and a main ram coupled to said pistons and movable towards the other of said platens upon supply of pressure fiuid to the cylinders, the axis of the ram being aligned with the point of intersection of the said diagonals and constituting the working axis of the press, and the columns being arranged so that each column is spaced from the horizontal plane through the working axis of the press.

References Cited by the Examiner UNITED STATES PATENTS 1,609,988 12/26 Bull 207--2 FOREIGN PATENTS 1,163,770 4/58 France.

1,261,559 4/61 France.

514,819 12/3 0 Germany. 1,112,488 8/61 Germany.

WILLIAM J. STEPHENSON, Primary Examiner.

CHARLES W. LANHAM, MICHAEL V. BRINDISI,

Examiners.

Claims

1. A PRESS COMPRISING A MAIN FRAME CONSISTING OF TWO PRESSURE PLATENS AND FOUR HORIZONTAL TENSION COLUMNS ON WHICH THE TWO PLATENS ARE MOUNTED IN PARALLEL SPACED RELATION TO EACH OTHER, EACH OF SAID COLUMNS EXTENDING FROM ONE PLATEN TO THE OTHER AND EACH COLUMN BEING SECURED TO BOTH PLATENS, THE COLUMNS BEING ARRANGED SO THAT, IN TRANSVERSE SECTION, THE AXES OF THE COLUMNS DEFINE THE CORNERS OF A PARALLELOGRAM HAVING DIAGONALS OF UNEQUAL LENGTH, A MAIN HYDRAULIC RECIPROCATING MEANS AND A RAM DRIVEN THEREBY, SAID RECIPROCATING MEANS BEING MOUNTED ON ONE OF SAID PLATENS SO THAT THE SAID RAM IS MOVABLE TOWARDS THE OTHER OF THE SAID PLATENS UPON OPERATION OF THE RECIPROCATING MEANS, THE AXIS OF THE RAM BEING ALIGNED WITH THE POINT OF INTERSECTION OF THE SAID DIAGONALS AND CONSTITUTING THE WORKING AXIS OF THE PRESS, AND THE COLUMNS BEING ARRANGED SO THAT EACH COLUMN IS SPACED FROM THE HORIZONTAL PLANE THROUGH THE WORKING AXIS OF THE PRESS.