US3234648A

US3234648A - Tool changers for forging presses

Info

Publication number: US3234648A
Application number: US282755A
Authority: US
Inventors: Knowles Keith
Original assignee: British Iron and Steel Research Association BISRA
Current assignee: British Iron and Steel Research Association BISRA
Priority date: 1960-12-14
Filing date: 1963-05-23
Publication date: 1966-02-15
Anticipated expiration: 1983-02-15
Also published as: GB938619A

Description

Feb. 15, 1966 K, KNO LES 3,234,648

TOOL GHANGERS FOR FORGING PRESSES Filed May 23, 1963 lNvEN-roIz ke z 'lw Know/es United States Patent Ofifice 3,234,648 Patented Feb.'15, 1966 3,234,648 TOOL CHANGERS FOR FORGING PRESSES Keith Knowles, Shetiieid, England, assignor to The British Iron and Steel Research Association Filed May 23, 1963, Ser. No. 282,755 6 Claims. (Cl. 29568) This invention relates to tool changers for forging presses.

In the use of conventional single-acting vertical pushdown type forging presses it is necessary after different forging operations to extract the forge tools and to insert new tools for subsequent operations. This tool changing is time-consuming and gives rise to delay between successive operations with different tools which is more than normally undesirable since this delay at the same time may give rise to or increase a requirement to reheat ingots during forging.

One object of this invention is to provide for automatically changing the tools in a forging press within a short time compared with that normally required.

In one aspect the present invention provides apparatus for changing tools in a forging press, comprising a tool carrying assembly for two sets of press tools, which assembly is arranged for controlled displacement whereby .a selected tool from either set may be located in a predetermined position, for the set in question, relative to a forging press, and means for transferring a selected tool from the associated predetermined position towards the press.

In order that the present invention may be clearly understood, the same will now be more fully described, by way of example, with reference to the drawings accompanying the provisional specification, in which:

FIGURE 1 is a side elevation of one embodiment with the sides of

hydraulic cylinders

12 and 13 broken away to show the pistons, and the catch on the press which engages the catch means on the tool changer shown in phantom lines; and

FIGURE 2 is a sectional end elevation of FIGURE 1 taken at A-A.

The illustrated apparatus is mounted in a framework 1 which is itself carried on, or formed integrally with, a chassis 2. The chassis 2 is provided with wheels 3 which allow the apparatus to be transported along a track 4 to a position at one end of the track in close proximity to a forging press (not shown) for initial tool loading and subsequent tool changing, and also away from the press for ease of maintenance or other operations on the apparatus itself, or on the press.

A double tool set carrying assembly is journalle d in bearings 5 fixably supported in the framework 1, and generally comprises two coaxial cylindrical units which will be referred to as the inner and outer tool units. The inner tool unit comprises two annular plates 6 carrying between them slotted guide members 7. These guide members are arranged symmetrically around the plates 6 with the slots of each pair in facing disposition, whereby press tools 8 having suitable flanges may be slidably located between the pairs of guide members in cartridge manner as more clearly indicated in FIGURE 2. The annular plates 6 are provided with openings 9 corresponding to the tool section for insertion and extraction of the tools.

The outer tool unit is of similar form to the inner tool unit and corresponding elements are denoted by the same reference numerals with the addition of an a.

The tools selected for insertion into the press are positioned about the vertical plane through the common cylindrical axis of the assembly as illustrated by the two uppermost tools 8 and 8a in FIGURE 2 and these particular tool positions are arranged to be in line with a predetermined tool receiving positions in the press. The press will be provided with guides to receive tools when the guides are appropriately positioned.

The inner and outer tool units are adapted for independent rotation by a common reversible motor 10 driving two wheels 11 carrying spring-biased pawls which cooperate with inwardly projecting teeth on the hub members 11a to form two oppositely acting ratchets so that drive in one direction rotates one tool unit with the other fixed, and drive in the other direction rotates the other unit with the first fixed. Individual positioning devices are associated with each tool position in the units whereby a selected tool, or tools one from each unit, are positioned for insertion into the press. These positioning devices co-operate with a detent which is actuated by a hydraulic cylinder 12 and which is introduced to lock the units when the selected tool or tools are suitably positioned.

The selected tools when positioned for insertion are, as described above, on a common axis with the respective tool receiving positions of the press, and also with actuators shown as hydraulic or pneumatic cylinders 13 employed to propel these tools into the tool guides of the press. It may be necessary to bridge any gap which would otherwise occur between the tool units and the press, and a suitable bridge assembly 14 is shown for this purpose. Also a location stop and catch assembly is provided for correct positioning of the tool units and bridge member relative to the press.

This catch assembly may comprise a pivotally mounted arm 15 pierced at one end by a vertical hole 15a and pivotally attached at its other end to the ram of a hydraulic cylinder 15b. When the tool changer approaches the press, the hydraulic cylinder 15b swings the end of the arm 15 pierced by the hole 15a upward, but subsequently permits it to drop when the pin 15c on the press catch 15d is beneath the hole.

To ensure locking of a tool in the press, the press tool guides are provided, at their ends nearer the apparatus, with detent mechanisms which are pushed to an inoperative position when a tool is inserted. However, the tool is pushed beyond the detent location and on withdrawing the rams of cylinders 13 the detents adopt operative positions to lock the tools in the press.

The above particular description has dealt only with insertion of tools and this will be the case for initial tool loading of the press, for example. For subsequent tool changes, one or both of the loaded tools are first extracted, and it will be seen that the tool units are already in the correct positions to receive the tools from the press. The rams of cylinders 13 are provided with suitable means for engaging the tools in the press to withdraw same, and they will, at the same time, push the press tool locking detents to their inoperative positions.

The cylinder rams may be provided at their ends with suitable, conventional quick-connecting coupling arrangements 13a comprising a taper lead-in and ball lock device, for example. Such a device would be employed for extraction of tools, the latter being provided with complementary devices. Means would then be required to re lease such locking devices when appropriate, and may comprise solenoids on the cylinder rams, for example. Suitable couplings may be purchased from the Hansen Manufacturing Company, of 4033 W. th Street, Cleveland, Ohio. The exact model selected will depend upon the nature of the complementary device carried by the tools to be changed.

It may be found desirable to taper the tool guide flanges at both ends to facilitate insertion and withdrawal of tools relative to the guides.

Although the invention has been described by way of example with reference to a particular embodiment it is not intended that it be limited thereto. Clearly various modifications can be \made in the above embodiment without departing from the scope of the invention; for example, individual driving means may be employed for independent rotation of the inner and outer tool units, either simultaneously, or otherwise, by use of gears, chains, or directly. Also the tool insertion and withdrawal means shown as cylinders 13 may be comprised by ball screw lead shafts. In other forms of the invention the tool bearing assembly may be in the form of a beam mounted on a frame for displacement along its axis by sliding, in a horizontal or vertical disposition, for example. Two sets of tools may be carried, being upper and lower tools for the present application to forging presses, with a pair of tools, one from each set, carried in slotted guide members in the upper and lower portions of two-tool housings arranged along the beam.

Common actuator means may be employed for insertion of the pair of tools from any housing into the press, or withdrawal from the press into the beam. Alternatively, individual actuator means may be associated with each set of tools, that is to say, with the upper and lower portions of the tool housingsf Again, as in the above-described embodiment of FIG- URES 1 and 2, the apparatus may comprise independently controllable tool carrying units, in this case the units being of parallel beam form. In embodiments of the latter form independent drive means and actuator means will be associated with each tool unit.

Furthermore the invention is not necessarily applicable to forging presses employing two changeable tools and may comprise a unit, or units, for one or more sets of tools as appropriate, although the invention has been developed with a view to particular application to automatic forging presses of the former kind.

I claim:

1. For association with a forging press having a pair of interchangeable tools, tool changing apparatus comprising a carriage movable towards and away from an associated press, a pair of first and second cylindrical tool magazines mounted on said carriage for rotation about a common axis disposed parallel to the plane of the carriage, first and second pluralities of slotted openings for receiving tools, said openings being respectively and circumferentially distributed in said magazines with the axes of said openings disposed parallel to said common axis, drive means to respectively independently rotate said magazines, locking means to lock said magazines against rotation with any selected pair of said openings, one from each plurality thereof, disposed in predetermined rotational angular positions, and tool transfer means aligned with said predetermined positions to eject tools from said selected openings towards said press and to withdraw tools thereinto from said press.

2. Apparatus according to claim 1 comprising catch means mounted on said carriage towards one axial end of said magazine to latch said carriage with said press during tool transfer therebetween.

3. Apparatus according to claim 2 comprising bridge means mounted on said carriage and including first and second slideways respectively aligned with said predetermined positions.

4. Apparatus according to claim 1 wherein said tool transfer means comprise a pair of hydraulic rams respectively aligned with said predetermined positions.

5. For association with a forging press having a pair of first and second tool carrying members arranged for pressing action by relative reciprocation along a predetermined axis and each adapted to receive interchangeable press tools: tool changing apparatus comprising a pair of first and second slideways disposed normally to said predetermined axis with one end of each slideway respectively adjacent predetermined positions of said tool carrying members, a first tool magazine including a plurality of slotted openings for receiving tools, said openings being disposed with their axes parallel to said slideways and which first magazine is mounted to move its openings along a first path remote from said press to traverse its openings successively into a first fixed position aligned with said first slideway adjacent the other end thereof, a second tool magazine including a plurality of slotted openings disposed with their axes parallel to said slideways and which second magazine is mounted to move its openings along a second path remote from said press to traverse its opening successively into a second fixed position aligned with said second slideway adjacent the other end thereof, drive means to respectively independently move said magazines along their respective paths, locking means to lock said magazines against movement with any selected pair of said openings, one from each magazine, respectively disposed in said fixed positions, and reciprocable tool transfer means aligned with said fixed positions adjacent the ends thereof remote from said press to eject tools from said selected openings along said slideways towards said press and to withdraw tools from said press along said slideways into said selected openings.

6. For association with a forging press having a pair of tool carrying members-for receiving changeable tools, tool changing apparatus comprising a first tool magazine carrying a plurality of tool holders and mounted to move each tool holder along a first path into a first position aligned with a predetermined position of one tool carrying member of an associated press, a second tool magazine likewise carrying a plurality of tool holders and mounted to move each tool holder carried thereby along a second path into a second position aligned with a pre determined position of the other tool carrying member of said press, said first and second paths lying wholly outside the confines of said press, means for independently driving each of said first and second magazines to move said tool holders along their respective paths; looking means to lock said first and second magazines with any selected tool holder thereof aligned in said first and second positions, respectively; and first and second tool transfer means respectively aligned with said first and second magazine positions to transfer selected tools between said magazines and press.

References Cited by the Examiner UNITED STATES PATENTS 2,363,208 11/ 1944 Sulzer.

3,134,350 5/1964 Danly 299 FOREIGN PATENTS 1,101,910 3/1961 Germany.

CHARLES W. LANHAM, Primary Examiner.

WILLIAM J. STEPHENSON, Examiner.

G. P. CROSBY, Assistant Examiner,

Claims

1. FOR ASSOCIATION WITH A FORGING PRESS HAVING A PAIR OF INTERCHANGEABLE TOOLS, TOOL CHANGING APPARATUS COMPRISING A CARRIAGE MOVABLE TOWARDS AND AWAY FROM AN ASSOCIATED PRESS, A PAIR OF FIRST AND SECOND CYLINDRICAL TOOL MAGAZINES MOUNTED ON SAID CARRIAGE FOR ROTATION ABOUT A COMMON AXIS DISPOSED PARALLEL TO THE PLANE OF THE CARRIAGE, FIRST AND SECOND PLURALITIES OF SLOTTED OPENINGS FOR RECEIVING TOOLS, SAID OPENINGS BEING RESPECTIVELY AND CIRCUMFERENTIALLY DISTRIBUTED IN SAID MAGAZINES WITH THE AXES OF SAID OPENINGS DISPOSED PARALLEL TO SAID COMMON AXIS, DRIVE MEANS RESPECTIVELY INDEPENDENTLY ROTATE SAID MAGAZINES, LOCKING MEANS TO LOCK SAID MAGAZINES AGAIST ROTATION WITH ANY SELECTED PAIR OF SAID OPENINGS, ONE FROM EACH PLURALITY THEREOF, DISPOSED IN PREDETERMINED ROTATIONAL ANGULAR POSITIONS, AND TOOL TRANSFER MEANS ALIGNED WITH SAID PREDETERMINED POSITIONS TO EJECT TOOLS FROM SAID SELECTED OPENINGS TOWARDS SAID PRESS AND TO WITHDRAW TOOLS THEREINTO FROM SAID PRESS.