US3452582A

US3452582A - Multistage machine tool

Info

Publication number: US3452582A
Application number: US607547A
Authority: US
Inventors: Ernst Faymonville
Original assignee: Malmedie und Co Maschinenfabrik GmbH
Current assignee: Malmedie & Co Mas Fab GmbH; Malmedie und Co Maschinenfabrik GmbH
Priority date: 1966-03-16
Filing date: 1967-01-05
Publication date: 1969-07-01
Anticipated expiration: 1986-07-01
Also published as: SE335316B; GB1156569A; CH443916A; DE1577036A1; NL6615903A

Description

y 1969 E. FAYMONVILLE 3,452,582

MULTISTAGE MACHINE TOOL Filed Jan. 5, 1967 7 Sheet o; 3

July 1, 1969 E. FAYMONVILLE MULTISTAGE MACHINE TOOL Sheet Filed Jan. 5, 1967 Ami fie INVENI'OI? y 1969 E. FAYMONVILLE 3,452,582

MULTISTAGE MACHINE TOOL Filed Jan. 5, 1967 Sheet 0 of s United States Patent 3,452,582 MULTISTAGE MACHINE TOOL Ernst Faymonville, Dusseldorf-Wersten, Germany, assignor to Malmedie & C0. Maschinenfabrik G.m.b.H. Filed Jan. 5, 1967, Ser. No. 607,547 Claims priority, application Germany, Mar. 16, 1966, M 68,783 Int. Cl. B21d 43/02, 45/00; B21j 11/00 U.S. Cl. 72-421 14 Claims ABSTRACT OF THE DISCLOSURE A multistage press wherein the workpieces are transferred seriatim to a series of successive stations and are ejected from female dies prior to transfer to the next station. In order to prevent uncontrolled travel of Workpieces in response to ejection, a back support is moved in front of each workpiece and intercepts it on ejection from the female die. The back supports cooperate with the ejectors to maintain the workpieces in requisite position for proper engagement by the transfer elements and, if the workpieces are hard to hold by the transfer elements alone, the back supports are installed in such a way that they travel with the transfer elements and assist such elements in transferring the workpieces from the preceding to the next-following stations.

Background of the invention The present invention relates to machine tools in general, and more particularly to improvements in automatic multistage presses or analogous machines wherein relatively short and hard-to-grip workpieces are treated in a series of stages at a plurality of successive working stations.

It is already known to treat ring-shaped, disk-shaped, circular plate-like or analogous workpieces whose axial length is but a fraction of their diameter in a series of stages at a plurality of successive working stations each of which accommodates a female die. The dies cooperate with rams which are movable into and from deforming engagement with workpieces, and the machine further comprises ejectors which expel partly finished or finished workpieces from the respective dies. A transfer mechanism whose holders grip ejected workpieces serves to transfer such workpieces from a preceding to the next-following working station. The holders of the transfer mechanism normally comprise pairs of gripping fingers or arms which are movable into and away from engagement with workpieces. Such holders are satisfactory when the workpieces are relatively long but are less reliable when the workpieces resemble flat disks, rings or like relatively short bodies. Additional problems arise if such workpieces are actually propelled from the female dies because the arms of the holders are often unable to intercept and to properly engage flying workpieces which resemble or comprise very short cones or rings. It happens frequently that, when an ejector is operated to expel the workpiece from a female die, the disengagement of the workpiece from the die occurs abruptly and the thus disengaged workpiece might move away from the ejector before it reaches the corresponding holder. In multistage presses wherein the rams are moved in a vertical plane, a workpiece which is not properly grasped by the holder during transfer from a preceding to the next-following station might fall into the machine to cause complete breakdown of or lengthy interruptions in operation. If the rams are reciprocated in a horizontal plane, workpieces which were permitted to fall are automatically discarded as scrap.

"ice

Accordingly, it is an important object of the present invention to provide a multistage machine which is constructed and assembled in such a way that the workpieces which are ejected from the tools at the working stations are compelled to assume requisite positions for satisfactory engagement by the elements of the transfer mechanism so that the waste is reduced to a minimum and the workpieces cannot disturb the operation of the machine.

Another object of the invention is to provide a multistage machine wherein the workpieces are prevented from performing uncontrolled movements with reference to the ejectors and transfer mechanism even if such workpieces are extremely flat, short, conical or otherwise configurated in a way which renders them hard-tohold by the elements of conventional transfer mechanisms.

A further object of the invention is to provide a machine wherein the transfer mechanism is assisted in performing its intended function to invariably prevent loss of workpieces during transfer from station to station.

An additional object of the invention is to provide a multistage machine for stepwise treatment of ring-shaped, disk-like, flat plate-like or analogous articles wherein proper retention of such articles by the transfer mechanism is guaranteed even if the articles tend to jump subsequent to ejection from the tools at the working stations.

A concomitant object of the invention is to provide a multistage machine of the above outlined character which can be utilized for shaping of different types of workpieces, wherein the movements of all parts can be automatically controlled, wherein proper retention and interception of ejected workpieces does not interfere with forward or return strokes of deforming tools, and wherein the provision of means for intercepting ejected workpieces contributes little, if anything, to bulkiness, floor space requirements and/or weight of the machine.

Summary of the invention Briefly outlined, one feature of the present invention resides in the provision of a machine wherein workpieces are treated in a series of stages at a plurality of successive equidistant working stations, particularly to a multistage press for treatment of workpieces whose diameter exceeds their axial length (such as washers, rings, disks and like substantially flat bodies). In its elementary form, the machine comprises a support which can constitute a component part of the machine frame, a series of work-supporting tools mounted on the support, one at each of the working stations and each preferably constituting a female die, ejectors provided at the working stations and being operative to expel workpieces from the respective tools, transfer means including a carriage and a plurality of work holders on the carriage, the holders being movable into and from supporting engagement with workpieces at the working stations and the carriage being movable with reference to the support to transfer each workpiece which is engaged by a holder from registry with a tool at a preceding station into registry with a tool at the nextfollowing station, and a plurality of back supports, one for each working station and each movable to and from an operative position in front of a workpiece in the respective tool to intercept such workpiece on operation of the associated ejector and to cooperate with such ejector to maintain the workpiece in requisite position for engagement by a holder.

If the workpieces resemble short cones or similar hardto-hold articles, the back supports are preferably movable with the carriage of the transfer means so as to remain in supporting engagement with workpieces during transfer from station to station.

The novel features which are considered as characteristic of the invention are set forth in particular in the appended claims. The improved machine itself, however, both as to its construction and its mode of operation, together with additional features and advantages thereof, will be best understood upon perusal of the following detailed description of certain specific embodiments with reference to the accompanying drawing.

Brief description of the drawing FIG. 1 is a fragmentary transverse vertical section through one working station of a multistage press which embodies the invention, the back supports being shown in retracted positions and the workpieces being held between the male and female tools upon completion of a deforming operation;

FIG. 2 illustrates the structure of FIG. 1 but with the back supports shown in operative positions upon completed retraction of male tools;

FIG. 3 illustrates the structure of FIG. 2 but showing a workpiece in a position it assumes on operation of the respective ejector when the workpiece is held by such ejector and the associated back support;

FIG. 4 illustrates the structure of FIG. 3 but with a holder shown in actual engagement with a workpiece which is still held between the ejector and the corresponding back support;

FIG. 5 illustrates the structure of FIG. 5 prior or subsequent to transfer of a workpiece from a preceding to the next following working station when the workpiece is engaged solely by the respective holder and is maintained in the path of the male tool; and

FIG. 6 is a fragmentary front elevational view of three adjoining working stations each of which accommodates a workpiece which is still engaged by the corresponding holder.

Description of the preferred embodiments Referring first to FIG. 1, there is shown a multistage press which comprises a support 1 resembling a platform and preferably forming part of the machine frame. The support 1 carries a set of horizontal work-supporting tools 2 here shown as female dies which can cooperate with male tools or rams 7 to shape workpieces 13 in a series of successive operations each of which is performed at a different working or treating station. FIG. 6 shows, by way of example, three equidistant working stations each of which accommodates a female die 2. The support 1 further carries a system of adjustable links 3a which are pivotable on horizontal pins 3b and support an elongated horizontal guide rail 30 for a slide or carriage 3 forming part of a transporting mechanism. The carriage 3 supports a row of equidistant work-engaging holders 4, best shown in FIG. 6, each of which comprises two crossed gripping arms or fingers movable into and away from engagement with a workpiece 13 subsequent to ejection of such workpiece from its socket in the respective female die 2. Each working station further accommodates a reciprocable ejector 2a which is constituted by the piston rod of a piston 2b which is installed in a horizontal double-acting cylinder 20. The ejectors 2a are disposed in a common horizontal plane and their forward ends can pass through central openings provided in the respective female dies 2 to eject the workpieces 13 from their sockets in response to forward strokes of the respective pistons 2b. The conduits for supplying fluid to and for evacuating fluid from the cylinders 20 are not shown in the drawing.

The rams 7 are mounted on a slide or carriage 8 which is movable toward and away from the working stations so that the working ends of the rams engage and deform the workpieces 13 when the slide 8 moves to the left and assumes the position shown in FIG. 1. The drive mechanism which reciprocates the slide 8 is of known design and its construction forms no part of the present invention. The same holds true for the drive which reciprocates the carriage 3 of the transporting mechanism, for the valves which control the flow of fluid into and from the cylinders 20 of the ejectors 2a, and for the drive which is used to move a set of novel back supports 6 to and from operative positions shown in FIG. 2. These back supports 6 resemble short cylinders having portions or stems 6a of reduced diameter which are reciprocable in horizontal bores provided therefor in a vertical plate-like carrier 5. Each back support 6 is biased toward the respective female die 2 (i.e., toward the exposed side of a workpiece 13 which is supported by such female die) by a resilient element which is shown in the form of a helical spring 14. The bias of springs 14 can be adjusted by nuts 6b which mesh with the stems 6a.

The carrier 5 is articulately connected with upper and

lower links

11a, 11 which are turnable on or with

horizontal pivot pins

12a, 12 mounted on a lower carriage or slide 9. This carriage 9 is reciprocable along a dovetailed guide rail 10 which is afiixed to or forms part of the support 1. The

parts

5, 9, 11, 11a, 12, 12a together form a parallel motion mechanism which can move the back supports 6 between the operative positions of FIG. 2 and the retracted positions of FIG. 1. The axes of the back supports 6 remain parallel with the axes of the ejectors 2a and each such ejector registers with one of the back supports 6 when the carrier 5 is held in the operative position shown in FIG. 2. The springs 14 will yield and will store energy when the ejectors 2a expel the workpieces 13 from the respective female dies 2 whereby the spring-biased back supports 6 cooperate with the ejectors 2a to maintain the workpieces 13 in requisite optimum positions for engagement by the fingers or arms of the holders 4.

The mechanisms which feed blanks to the female die 2 at the first or foremost working station and the mechanisms which receive finished workpieces from the holder 4 that removes such finished workpieces from the female die 2 at the last working station are known in the art and are not shown in the drawing. Furthermore, the machine comprises a suitable programming unit which synchronizes movements of the slide 8 with movements of the ejectors 2a, carriage 3 and

links

11, 11a to carry out the operations in a desired sequence. The

links

11, 11a are oscillated with or relative to their

pivots

12, 12a to move the back supports 6 to and from operative positions.

When moved to retracted positions (see FIG. 1), the ejectors 2a serve as stops to limit the forward strokes of the rams 7.

The operation is as follows:

FIG. 1 illustrates one of the rams 7 in its forward end position, i.e., in a position corresponding to that upon completion of a working or deforming stroke. The carrier 5 maintains the back supports 6 in their retracted positions in which such back supports cannot interfere with forward and/or return strokes of the rams 7. The arms or fingers of the holders 4 are moved away from each other so that such arms are out of the way and cannot obstruct movements of the rams 7 and/or the ejection of workpieces 13 from the respective female dies 2.

When the rams 7 are retracted (see FIG. 2), the

pivots

12, 12a for the

links

11, 11a are rotated in a counterclockwise direction to lift the carrier 5 and to move the end faces of the back supports 6 against the exposed sides of the workpieces 13. In the next step which is illustrated in FIG. 3, the ejectors 2a are moved forwardly and expel the workpieces 13 from the sockets of the female dies 2 whereby the workpieces push the back supports 6 in a direction to the right, as viewed in FIG. 2, and to the positions shown in FIG. 3. Each workpiece 13 is then clamped from opposite sides by one of the ejectors 2a and by the corresponding back support 6. Thus, the axial length of the workpieces 13 can be extremely small or very large without affecting the retaining action of the

parts

2a, 6. This is particularly important when the workpieces 13 are flat disks or rings or very short cones which are hard to hold by the arms of the holders 4.

The next step is illustrated in FIG. 4. The holders 4 have moved their arms into actual engagement with the adjoining workpieces 13, but such workpieces are still clamped between the ejectors 2a and the corresponding back supports 6. Thus, no workpiece is released prior to proper engagement and retention by one of the holders 4. In the next-following step (see FIG. 5 or 6), the

pivots

12, 12a return the back supports 6 to their retracted positions and the pistons 2b retract their ejectors 211 so that the workpieces 13 are supported solely by the arms of the respective holders 4. The carriage 3 is then shifted along the upper guide rail 30 to move the workpieces 13 from registry with the female dies 2 at the preceding working stations into registry with the female dies at the nextfollowing working stations. The ejectors 2c are moved forwardly to an extent necessary to determine the length of forward strokes of the rams 7, and the rams are moved forwardly to press the workpieces against the respective female dies 2. The arms of the holders 4 are disengaged from the workpieces as soon as such workpieces are safely held between the female dies and the rams. The next working cycle is then carried out in a manner as described above.

The last holder 4 can deliver finished workpieces to a chute or to another receiving device for transfer of finished workpieces to storage or to a further machine. The female die 2 at the first or foremost working station will receive a blank during intervals when the holders 4 transfer workpieces from preceding to the next-following stations.

If the nature of workpieces 13 is such that they cannot be properly retained by the arms of the holders 4, the carriage 9 for the carrier 5 is reciprocated with the carriage 3 for the holders 4 and the back supports 6 remain in operative positions until the workpieces 13 are brought into registry with the female dies 2 at the next-following working stations. Thus, the back supports 6 can cooperate first with the ejectors 2a to clamp the workpieces 13 on ejection from the female dies 2, and such back supports can thereupon cooperate with the holders 4 to assist the holders in transferring workpieces from station to station The

carriages

3 and 9 will be reciprocated in syn chronism if the workpieces 13 resemble short cones or if such portions of the workpieces which are engaged by the holders 4 resemble short cones. A short cone is likely to slip out of the arms of a holder 4 but, when simultaneously engaged by a back support 6, it can be safely transferred from station to station.

The machine may comprise two, three, four or more working stations, depending on the desired number of treatments to which a blank must be subjected in order to assume a desired size and/or shape.

Without further analysis, the foregoing will so fully reveal the gist of the present invention that others can, by applying current knowledge, readily adapt it for various applications without omitting features which fairly constitute essential characteristics of the generic and specific aspects of my contribution to the art.

What is claimed as new and desired to be protected by Letters Patent is set forth in the appended claims.

I claim:

1. A machine wherein workpieces are treated in a series of stages at a plurality of successive working stations, comprising a support; work-supporting tools mounted on said support at each of said stations; a plurality of movable ejectors provided at said stations, each of said ejectors engaging one of said workpieces for moving the same from its tool-engaging position into a transfer position; transfer means including a carriage and a plurality of work holders on said carriage, said holders being movable into and from supporting engagement with workpieces at said stations when the same are in said transfer positions thereof and said carriage being movable with reference to said support to transfer each workpiece which is engaged by a holder from said transfer position at one station into the transfer position at the next following station; means for moving said movable ejectors so that the same move each of said workpieces engaged by the same from their tool-engaging positions into their transfer positions; and a plurality of back supports, each of said back supports adapted to engage a corresponding workpiece in its tool-engaging position and move together with the same while said workpiece is moved into said transfer position by movement of the corresponding ejector so that each workpiece is fully supported and held by an ejector and the corresponding back support during movement of the workpiece from its tool-engaging position into its transfer position in which latter position it is then engaged by a holder for transfer to the next following station.

2. A machine as defined in claim 1, particularly a multi-stage press for shaping of workpieces whose diameter exceeds the axial length thereof, wherein each of said tools is constituted by a female die and wherein each of said ejectors is reciprocable with reference to the respective die.

3. A machine as defined in claim 2, wherein each of said back supports is reciprocable in parallelism with said ejectors and registers with one of said ejectors in the operative position thereof, and further comprising resilient means for biasing said back supports aginst the workpieces in a direction toward the respective ejectors.

4. A machine as defined in claim 3, further comprising carrier means for moving said back supports to and from operative positions.

5. A machine as defined in claim 4, further comprising link means pivotable about predetermined axes and articulately coupled to said carrier means to effect movement of back supports to and from said operative positions.

6. A machine as defined in claim 4, wherein said carrier means is provided with a plurality of parallel bores and each of said back supports comprises a portion which is reciprocable in one of said bores, said resilient means comprising springs operating between said carrier means and said back supports to urge such back supports toward the corresponding ejectors, said back supports being arranged to yield to workpieces and to deform said springs in response to operation of the respective ejectors.

7. A machine as defined in claim 1, further comprising a second carriage for said back supports, said second carriage being movable with said first mentioned carriage so that the back supports can remain in engagement with workpieces during transfer between successive stations.

8. A machine as defined in claim 7, wherein said support comprises parallel guide means for said carriages and wherein each of said carriages is reciprocable along the respective guide means through distances corresponding to those between said tools.

9. A machine as defined in claim 1, wherein said ejectors are reciprocable in a common horizontal plane and said carriage is reciprocable in a horizontal path at a level above and at right angles to said ejectors, said back supports being movable upwardly and axially of said tools to said operative positions.

10. A machine as defined in claim 1, further comprising second tools reciprocable into and away from deforming engagement with workpieces carried by said first mentioned tools when the back supports are moved away from said operative positions.

11. A machine as defined in claim 1, further comprising resilient means for biasing said back supports against the workpieces and toward the respective ejectors and means for adjusting the bias of said resilient means.

12. A machine as defined in claim 1, wherein said holders have gripping arms which are movable with reference to each other and wherein the work-pieces resemble substantially flat bodies.

13. A machine as defined in claim 1, wherein said ing a parallel motion mechanism for moving said back 5 supports to and from operative positions.

References Cited UNITED STATES PATENTS 2,687,660 2,721,343 10/1955 Friedman 10--12 8/1954 Friedman 72-346 10 8 3,120,770 2/1964 Hoyt 10-12 3,274,626 9/ 1966 Van de Mecrendonk 10-12 FOREIGN PATENTS 1,107,489 5/1961 Germany.

CHARLES W. LANHAM, Primary Examiner.

E. M. COMBS, Assistant Examiner.

US. Cl. X.R.