US3468155A

US3468155A - Forging press

Info

Publication number: US3468155A
Application number: US591238A
Authority: US
Inventors: Keith Ross
Original assignee: Davy Loewy Ltd
Current assignee: Davy Loewy Ltd
Priority date: 1966-11-01
Filing date: 1966-11-01
Publication date: 1969-09-23
Anticipated expiration: 1986-09-23

Description

Sept. 23, 1969 K. ROSS 3,468,155

FORGING PRESS Filed Nov. 1, 1966 INVENTOR f'fe/fh 905$ BY flfi ATTORNEY United States Patent C) 3,468,155 FORGING PRESS Keith Ross, Shefiield, England, assignor to Davy and United Engineering Company Limited, Sheffield, Yorkshire, England Filed Nov. 1, 1966, Ser. No. 591,238 Int. Cl. B21j 13/04; B21d 37/10; B30b 1/32 US. Cl. 72-456 8 Claims ABSTRACT OF THE DISCLOSURE A forging press, particularly that type of press known as a draw-down press, has a fixed base and a frame comprising at least two columns extending through the base and slidably movable relative thereto, with a pair of crossheads located on opposite sides of the base connecting the columns together. At least one hydraulic piston and cylinder assembly acts between the base and one crosshead to drive the other crosshead towards the base and, in order to resist distortion of the frame when the frame is subjected to eccentric loading, guide means for the columns are carried by at least one of the assemblies at a position spaced from the base.

This invention relates to forging presses and particularly to that type of forging press (hereinafter referred to as a press of the type described) which has a fixed base and two or more columns slidably movable in the base and connected together by crossheads located on opposite sides of the base. A press piston and cylinder assembly or more than one such assembly is or are arranged between the base and one crosshead to drive the other crosshead, carrying one of the forging tools, towards the base which carries the other tool. A press of the type described is commonly called a draw-down press, and usually the press is arranged with the columns vertical and the crossheads horizontal.

conventionally, each movable column is guided by a pair of guide sleeves arranged in the base and spaced from one another. The short distance that is available between the guide sleeves is, however, not always sufficient safely to resist the turning moment applied to the frame constituted by the crossheads and columns, when that frame is subjected to eccentric loading.

To provide increased resistance to the turning moment, it has been previously proposed to provide a guide stalk which is secured in the base and which guides the lower cross-head. In this way, the distance between the guiding points for the frame is increased, but the cost is proportionally increased.

In accordance with one aspect of the invention a drawdown press of the type described has the cylinder of the press piston and cylinder assembly or of one such assembly secured to the base and guides for guiding the columns are carried by that cylinder at a point or points spaced from the base. In this way, the advantages of the previously proposed guide stalk are attained, without a substantial increase in expense.

The invention will be more readily understood by way of example from the following description of a draw-down press in accordance therewith, reference being made to the accompanying drawing, in which FIGURE 1 is a side view of the press, partly in section, and

FIGURE 2 shows a modification.

In the drawing, the base is shown at 12, this base being securely mounted on foundations. The frame comprises four upright columns, two being shown at 13, which pass through bores 14 in the base 12, and which are connected together by an upper crosshead 15 and a lower crosshead Patented Sept. 23, 1969 16 located above and below the base 12 respectively. The upper crosshead 15 carries a tool holder 17, a tool being indicated at 18. The lower tool holder 20 is secured on the base 12 between the columns 13 and, in turn, carries a tool indicated at 21. In an alternative arrangement two upright columns only can be provided.

For the sake of simplicity, lifting cylinders of the press have been omitted from the drawing, but the main press piston and cylinder assembly is indicated as comprising a cylinder 22 secured in an opening 23 formed in the base 12, and a piston 24 protruding from cylinder 22 and engaging the lower crosshead 16 through a press pad 25.

Each column 13 is guided, firstly, by a guide sleeve 26 which is disposed in an enlarged opening formed at the upper end of the respective bore 14. Secondly, each column is guided by a guide member 27 which is carried on a ring 28 secured to the lower extremity of the cylinder 22, and which engages and guides the relatively movable column 13.

It will be seen that the two guide points, provided by the sleeve 26 and the guide member 27 for each column, are well spaced apart vertically and are therefore well able to resist any turning moment in the frame, produced by eccentric loading during forging. Furthermore, this spacing of hte guide points is provided without the provision of a guide stalk or additional element and therefore without undue additional expense.

It is not essential to provide the ring 28 since the columns may be guided directly by the cylinder 22. Also, where ring 28 is provided, it may be mounted on the cylinder 22 so that the ring can pivot slightly to equalise the stresses, on the four guiding points, arising under eccentric loading of the columns when the workpiece is to the left or right, in relation to FIGURE 1, of the vertical axis of the press. Under such eccentric loading the columns will bear against the sleeves 26 and a column of each pair will bear against its associated guide member 27 and ring 28 which will pivot slightly and thereby the load will also be taken by the other column of the pair.

In the modification of FIGURE 2, the guide sleeves 26 are dispensed with and the columns 14 are guided entirely by the cylinder 22 which, in this case carries a further set of guide members 30 mounted on a ring 31 which is disposed on the cylinder immediately below the base 12.

It will be appreciated that more than one press piston and cylinder assembly may if desired be employed between the base 12 and the lower cross-bed 16. In that case, it is necessary only for the cylinder of the central assembly to be provided with the

guides

27 or 27 and 30 for the columns 13. However, if there are more than tWo cylinders, each column may be guided by the cylinder nearest to it.

I claim:

1. A forging press comprising a fixed horizontal base, a frame comprising at least two vertical columns extending through the base and slidably movable in a direction parallel to their length relative to the base, upper and lower crossheads connecting said columns together at their upper and lower ends respectively, at least one hydraulically operable piston and cylinder assembly arranged with its cylinder secured to the base and its piston acting against the lower crosshead to drive the upper crosshead towards the base, and guide means in contact with each of said columns carried by the cylinder of said assembly at a position spaced from the base.

2. A forging press as claimed in claim 1 in which the columns are guided by further guide means carried by said assembly and spaced vertically from said other guide means.

3. A press according to claim 1 in which the columns are also guided by sleeves mounted in the base.

4. A press according to claim 3 in which the sleeves are secured near the top of the base and the guide means are located near the lower extremity of the cylinder.

5. A press according to claim 1 in which the guide means are mounted on a ring carried by the cylinder.

6. A press according to claim 5 in which the ring is mounted on the cylinder so that it can pivot to equalise the stresses on the guiding points.

7. A forging press comprising a fixed base, a frame comprising at least two columns extending through the base and slid-ably movable relative thereto, a pair of crossheads located on opposite sides of the base and connecting said columns, at least one hydraulic piston and cylinder assembly acting between the base and one crosshead to drive the other crosshead towards the base, and guide means in contact with each of said columns carried by at least one of said assemblies at a position spaced from the base.

8. A forging press comprising a fixed base, a frame comprising at least two columns extending through the base and slidably movable relative thereto, a pair of crossheads located on opposite sides of the base and connecting said columns, at least one hydraulic piston and cylinder assembly acting between the base and one crosshead to drive the other crosshead towards the base, a

References Cited UNITED STATES PATENTS 2,869,177 1/1959 Jurgeleit 72456 3,024,676 3/1962 Howahr 72-456 3,158,046 11/1964 Steinfort 72-453 3,243,988 4/1966 Groos 100214 FOREIGN PATENTS 710,780 6/1954 Great Britain.

CHARLES W. LANHAM, Primary Examiner G. P. CROSBY, Assistant Examiner US. Cl. X.R. 100-269