US3910095A

US3910095A - Mechanism for stripping a drawn container from the punch of a deforming tool

Info

Publication number: US3910095A
Application number: US470260A
Authority: US
Inventors: Wilhelm Hortig
Original assignee: KM Engineering AG
Current assignee: KM Engineering AG
Priority date: 1973-05-25
Filing date: 1974-05-15
Publication date: 1975-10-07
Anticipated expiration: 1992-10-07
Also published as: BR7404166D0; IT1012709B; NL7406806A; AU474533B2; DE2332851B2; AU6908174A; DD114356A5; ES426667A1; DE2332851A1; DE2365766B2; SU516335A3; CH569527A5; DE2365766A1; JPS5027760A; DK284474A; GB1466189A; AT331617B; ATA425674A; DE2332851C3; CS176278B2

Abstract

The combination is used in the mechanism for forming and stripping a container having a mouth wherein the container is formed on a punch during the inserting portion of a deformation stroke through a deforming die and stripped from the punch during the withdrawing portion of the deformation stroke. An annular stripper member is located ahead of the deforming die and is disposed around and in a zone of movement during the deformation stroke. The stripper member is effective to strip the container from the punch during the withdrawing portion of the deformation stroke. Beveled means is adapted to act upon the peripheral edge of the mouth of the container against a peripheral edge section of the deforming die. Consequently, a conically-shaped widened portion is formed along the peripheral edge of the container mouth. The beveled means is effective to form the conically shaped widened portion toward the end of the inserting portion of the deformation stroke. The stripper member includes a stripper surface disposed obliquely with respect to the axis of the punch and is effective to abut the widened mouth portion on the withdrawing portion of the stroke thereby causing the container to be removed from the punch.

Description

Klnited States Patent [191 Hortig Oct. 7, 1975 1 MECHANISM FOR STRIPPING A DRAWN CONTAINER FROM THE PUNCH OF A DEFORMING TOOL Wilhelm Hortig, Auerbach, Germany 22 Filed: May 15, 1974 21 App]. No.: 470,260

[75] Inventor:

[30] Foreign Application Priority Data May 25, 1973 Switzerland 7570/73 [52] US. Cl. 72/344; 72/345; 72/346; '72/361 [51] Int. Cl. B21D 45/08 [58] Field of Search 72/344, 345, 346, 361

[56] References Cited UNITED STATES PATENTS 3,295,351 l/1967 Jacobs 72/344 3,418,839 12/1968 Hlavac 72/344 FOREIGN PATENTS OR APPLICATIONS 1,117,905 3/1956 France 72/345 150,377 4/1904 Germany 72/344 Primary ExaminerLowell A. Larson Assistant Examiner-Joseph A. Walkowski Attorney, Agent, or Firm-Neil F. Markva [57] ABSTRACT The combination is used in the mechanism for forming and stripping a container having a mouth wherein the container is formed on a punch during the inserting portion of a deformation stroke through a deforming die and stripped from the punch during the withdrawing portion of the deformation stroke. An annular stripper member is located ahead of the deforming die and is disposed around and in a zone of movement during the deformation stroke. The stripper member is effective to strip the container from the punch during the withdrawing portion of the deformation stroke. Beveled means is adapted to act upon the peripheral edge of the mouth of the container against a peripheral edge section of the deforming die. Consequently, a conically-shaped widened portion is formed along the peripheral edge of the container mouth. The beveled means is effective to form the conically shaped widened portion toward the end of the inserting portion of the deformation stroke. The stripper member includes a stripper surface disposed obliquely with respect to the axis of the punch and is effective to abut the widened mouth portion on the withdrawing portion of the stroke thereby causing the container to be removed from the punch.

18 Claims, 8 Drawing Figures U.S. Patent Oct. 7,1975 Sheet 1 of5 3,910,095

U.S. Patent Oct. 7,1975 Sheet 2 of 5 3,910,095

Fig. 2 i L ll US. Patent Oct. 7,1975 Sheet 3 of5 $910,095

US. Patent Oct. 7,1975 Sheet 4 of5 3,910,095

US. Patent Oct. 7,1975 Sheet 5 of5 3,910,095

MECHANISM FOR STRIPPING A DRAWN CONTAINER FROM THE PUNCH OF A DEFORMING TOOL BACKGROUND OF THE INVENTION The present invention refers to a mechanism for stripping a beaker-shaped container provided with a widened mouth, formed without a seam by deepdrawing and/or reduction-drawing, from the punch of a deforming tool, especially on an automatic multistage press, with a stripper member arranged in the zone of movement of the punch, which forces the container off the latter as the punch returns.

Deformation presses used for the production of seamless metal containers are known to require strippers which strip the shaped containers, for example, sheet steel shells for tins, from the punch as it returns. Consequently, the containers can be seized by the awaiting conveyor means, e.g., tongs, grippers, etc and transferred to the next deformation station or to the delivery respectively.

Known strippers are annular stationary members surrounding the punch concentrically, against which the top edge of the workpiece strikes as the punch returns. The workpiece is held stationary with respect to the punch as it returns further and is thereby released from the periphery of the punch. The conveyor means then immediately seize the workpiece as it comes free and convey it further laterally in the direction of feed.

These known strippers are burdened with a series of disadvantages which hitherto could not be eliminated in spite of systematic endeavours.

One of the difficulties encountered results, for example, from the effective surface of the stripper lying parallel with the irregular annular surface of the workpiece facing it. Consequently, for transmission of the stripping force merely the narrow irregular annular surface of the top edge of the workpiece is available. Above all, however, it must be observed in this case that the top edge of the shaped workpiece which is to be stripped offis because of the unavoidable forming oflobes made wavy in shape; i.e., it exhibits irregular recesses and projections which offer the stripper as a rule only very small areas of engagement. The consequence of this is that the stripping force is transmitted to the body of the container to one side and this is jammed or deformed respectively or damaged in some other fashion. This is associated generally with an interruption in operation if not actual damage of expensive parts of the tool.

SUMMARY OF THE INVENTION These disadvantages are to be eliminated by the present invention. The mechanism forming the object of the invention includes a stripper member having a stripper face running obliquely with respect to the axis of the punch and being matched to the inclination of the widened mouth of the container. In at least one deformation stage of any press, a beveled means or widener member is so arranged and positively coupled with the downward movement of the punch, that toward the end of the deformation stroke. I

In accordance with a special embodiment, the strip per member is supported movably on the outer face of the punch. The upwards stroke of the stripper member is limited by a stationary holder, i.e., one independent of the movement of the punch. The punch includes a striker means that is laterally displaced ahead of the top edge of the die. The distance of displacement is so selected that the stripper lies with the Widener beveled means against the mouth of the container at the bottom of the deadpoint of the zone of movement for the punch.

The stationary holder can be a holder-ring surrounding the punch concentrically. The striker can be formed in the shape of an annular shoulder arranged on the periphery of the punch.

The stripper and the widener member form a single part the bottom bevel of which provides both the stripper face and also the widener face.

In accordance with another feature, the outer surface of the combined stripper and widener member is conically tapered upwardly at least in its upper half. The holder is formed in the shape of a trap-bush supported concentrically with the axis of the punch. The bore of the holder is coordinated with the eonicity of the stripper and widener member. An annular flange is located at the upper face of the trap-bush and points radially toward the axis of the punch.

In accordance with a further embodiment of this invention, the stripper is a cylindrical sleeve fastened to the press frame. A row of stripper fillets are located in the bottom section of the frame and project from the inner wall of the stripper in the direction of the axis of the punch. Longitudinal grooves having a shape corresponding to the stripper fillets are located along the periphery of the punch and run parallel with respect to the axis of the punch. The bottom faces of the stripper fillets exhibit a bevel which corresponds with the required angle of widening of the container mouth.

BRIEF DESCRIPTION OF DRAWINGS Other objects of this invention will appear in the following description and appended claims, reference being made to the accompanying drawings forming a part of the specification wherein like reference characters designate corresponding parts in the several views.

FIG. 1 is a simplified section of the first embodiment and shows the punch at the bottom deadpoint of the deformation stroke,

FIG. 2 shows the embodiment shortly after stripping of the shaped container,

FIGS. 30 and 3b illustrate the construction of a stripper,

FIGS. 4 and 5 show two further embodiments, and

FIGS. 6 and 7 illustrate constructional details.

DESCRIPTION OF SPECIFIC EMBODIMENTS The selected embodiments refer to the deformation stage in a reduction-drawing press upon which beakershaped shells for tins are produced from sheet steel. The basic idea of the invention can however be realized in any desired stage of deformation in known deepdrawing presses, reduction-drawing presses and obviously also in a combination of these two types of press.

The mechanism displayed in FIGS. 1 and 2 with inessential details omitted exhibits a reduction-drawing punch I die 2. The die 2 is provided with a known but not shown reduction-drawing ring into which the workpiece to be deformed is rammed by the punch and reduced in diameter and in respect of its wall-thickness.

The reduction-drawing punch l, hereinafter only called the punch, exhibits a punch head la which is connected detachably to the punch body 1b by means of a fixing-pin 3.

1 A known pre-stripper 4 is supported in the central bore of the punch head la. The frusto-conical stripper head 4a registers in a correspondingly shaped recess 5 of the punch head la. A spiral spring 6 biases the prestripper 4 in its bottom position in which the prestripper head 4 projects from the recess 5.

The stripping movement of the pre-stripper 4 is limited by an ejector head 46 which is screwed into the axial bore in the pre-stripper and the top part of which serves as the spring plate for the spiral spring 6.

The pre-stripper 4 is a hollow body having an axial bore 4b open at both ends. The punch body 1!; has an axial bore 7 which can be connected to a source of compressed air at connection 8. See FIG. 2.

The reduction-drawing punch 1 is held onto a clamphead 10 by a clamp bolt 9 and driven to and fro by a known but not shown mechanism, for example, a crank gear. Between the punch holder 1 1 and the bottom face of the clamp-head 10, a setting-washer 12 is arranged.

The punch 1 provided with a shoulder 13 lies in accordance with FIG. 1 at its bottom deadpoint at which the deformation process has ended and the return of the punch is beginning. The workpiece clinging to the periphery of the punch, in this case a circularcylindrical shell 14 for a tin, is during the return of the punch pulled up with it and must then as soon as the punch has left the die be stripped from the periphery of the punch. For this purpose, a stripper 15 is disposed on the outer surface of punch head In. Stripper 15 can slide along the periphery of the punch once a predetermined limiting force has been exceeded. The bottom headpoint position is reached when the punch shoulder 13 lies against the end surface of the stripper 15. See

FIG. 1.

The stripper l5 exhibits a sleeve 16 the bottom edge of which, facing the die, has a conical taper l7 pointing downwards. The sleeve 16 is held against the periphery of the punch by friction by two friction-rings l8 supported in corresponding annular grooves, so that the stripper 15 during the upwards stroke of the punch 1 is taken by the latter with it. Stripper 15 includes a slight conical surface that encounters the likewise conically formed inner surface of a stationary holder 20. Consequently, stripper 15 is held stationary while the punch l withdraws upwards. During this relative move ment between the punch l and the stripper 15, the tinshell 14 seated on the bottom end section of the punch is stripped off.

The tin shell 14 is then taken over and conveyed onward by the conveyor member which is standing by. The mouth of the tin shell or container 14 experiences a widening effect by the conical taper 17 on the stripper 15 toward the end ofthe reduction-drawing or deformation stroke. The conical taper constitutes beveled means that is effective to form a conically shaped widened portion along the periphery of the container mouth 19. The conically shaped widened portion 19 is laid against a correspondingly shaped annular surface of peripheral edge section of the deforming die or else experiences widening without support to its outer surface. Distance 11 of the shoulder 13 from the top edge of the die is so selected that stripper 15 lies with its widener bevel 17 against the container mouth at the bottom deadpoint of the deformation stroke for the punch.

The Widener bevel 17 of stripper 15 forms an angle of about 20 to 40 to the horizontal. However, this angle can vary within wider limits in actual practice. In

this embodiment, the stripper surface and the Widener means for forming a conically shaped widened portion along the periphery of the mouth are constituted by this same bevel 17 on stripper 15.

Stripper holder 20 includes a holder ring 21 that concentrically surrounds punch 1. Ring 21 has an annular flange 22 projecting inwardly at the top portion thereof and is closely fitted against the peripheral face of punch 1. A stirrup 23 is slidably disposed on a holder plate 24 and holds ring 21 in place. Clamp bolts 25 fasten the plate 24 unto a holder bar 26 which is fastened to the frame of the press. Holder 20 also includes holder magnets 47 which hold the stripper 15 firmly once it is in a stationary seated position.

The specific embodiment as discussed hereinabove accomplishes two functions. First, the stripper 15 forms a stripping bevel in the shaped tin-shell 14 in the zone of its mouth. Secondly, the tin-shell 14 is stripped from the periphery of the punch 1. After the stripping bevel is shaped at the conical mouth, stripper 15 moves with punch l and tin-shell 14 out of the position shown in FIG. 1 and moves upwardly until stripper 15 encounters holder 20. See FIG. 2. In this position, the conically shaped mouth-face of tin-shell 14 is pressed against the conical stripper face 17 as the punch 1 continues its upward stroke. Consequently, tin-shell 14 is stripped from the periphery of the punch 1. The conically shaped portion of the tin-shell 14 provides a complete contact uniformly over a large surface between the stripper 15 and the tin-shell 14. Therefore, it is possible for a stripping force to be transmitted without any deformation of the thin-walled portion of the tin-shell 14. The effective stripper face 17 is totally independent of the possible occurrence of forming lobes.

Another feature of the disclosed mechanism overcomes another possible problem occurring during the formation of the tin-shells. It is possible that one or more lobes may project upwardly from the circumference of the mouth of the tin-shell so that even after the tin-shell has been stripped off from the punch, that the lobes will lie above the bottom edge of the stripper 15. Consequently, lateral conveyance of the tin-shells away from the stripper is prevented. During this process, the tin-shells can be deformed or jammed thereby severely impairing the flow of production. This problem is overcome by the further feature of the invention as described hereinbelow.

Stripper 15 has eight blind bores offset with respect to each other by 45 respectively. Spring-loaded thrusters 27 are slidingly supported in each of the bores. A spiral spring 28 biases each thruster outwardly from the bores. A stop 30 projects outwardly from each thruster into a longitudinal groove 29 thereby limiting the stroke of each thruster. Thrusters 27 include thrustcheeks 27a which project radially outwardly to uniformly engage against the irregular rim of the mouth of the tin-shell 14 being formed. Thrusters 27 thereby set themselves against the top edge of the tin-shell l4 and resiliently force it downwardly until the top edge of the tin-shell lies below the stripper 15. Thus, a collision between tin-shell 14 and stripper 15 is avoided during the onward conveyance to the next working zone.

FIG. 2 shows tin-shell l4 shortly after stripping from punch 1. Here the left hand edge of the mouth at point 32 exhibits an extraordinarily high lobe which has been forced downwardly by thruster 27.

After the stripping process, stripper is held in the position shown in FIG. 2 by permanent magnets 47. Stripper 15 remains stationary until the shoulder 13 on punch 1 engages it during the next downward stroke of punch 1. FIG. 2b shows the yet undeformed tin-shell blank 33.

Another embodiment of a mechanism made in accordance with this invention is shown in FIG. 4. The reduction-drawing punch 1 includes a frustoconical bevel shoulder 34 constituting beveled means adapted to act upon the peripheral edge of the mouth of the tin-shell being deformed. The shoulder 34 acts on the mouth of the tin-shell toward the end of the deformation stroke thereby taking over the function of the Widener bevel 17 shown in the embodiment of FIG. 1. The substantially cylindrical stripper 35 is held stationary by stirrup 36 which is fastened to a slidable holder plate 24 in this particular embodiment. Clamp bolts 25 are used to attach holder plate 24 to the holder bar 26. In this embodiment, in the earlier embodiment, the mechanism is used for forming and stripping a container having a mouth wherein the container is formed on a punch during the inserting portion of a deformation stroke through a deforming die and stripped from the punch during the withdrawing portion of the deformation stroke.

Stationary stripper includes 8 inwardly projecting stripper fillets 37 along its bottom portion. Fillets 37 include stripper faces 37 lying obliquely with respect to the axis of the punch 1. Fillets 37 project into longitudinal grooves 39 which are arranged on the peripheral surface of the reduction-drawing punch. Grooves 39 are parallel with respect to the axis of punch 1. Fillets 37 slide within the grooves 39 during the operation of the punch 37 and consequently lie at least partially within the contour of the punch.

Eight thrusters 38 are arranged around the periphery of stripper 35 and offset with respect to each other by 45. Thrusters 38 are slidably mounted within blind bores under spring pressure and prevented from dropping out by stops such those shown in the embodiment of FIG. 2. Thrusters 38 are circular-cylindrical steel pins having inwardly projecting lugs 38a disposed at their bottom ends. Lugs 38:! correspond to lugs 27a in the embodiment of FIG. 2.

In operation of this embodiment, the mouth of the tin-shell is first widened toward the ends of the stroke by the punch shoulder 34. Upon return of the punch 1,

the tips of the stripper fillets 37 catch in the mouth of the tin-shell. Stripper faces 37 are laid against the inner conical annular face of the widened portion of the mouth and the tin-shell is subsequently stripped off.

Occasionally, it ispossible that a lobe that is relatively high and projecting out radially from the tin-shell will come between two adjacent thrusters 38. Again, it is possible that the stripped tin-shell may collide with the bottom edge of stripper 35 during lateral conveyance thereof. To preclude the possibility of this problem, a further embodiment of the invention is shown in FIG. 5.

The embodiment of FIG. 5 shows a punch 1 having a widener shoulder (not shown) corresponding with shoulder 34 as shown in the embodiment of FIG. 4. A gripper mechanism 38 is located above the die 2 and includes gripper cheeks 39 which embrace a stripped tin-shell 14 or the tin-shell blank 40 yet to be deformed.

with the embodiment as shown in FIG. 4 but does not include thrusters 38. An annular release plate 41 surrounds the stripper 35 and is connected to the rod 42 of a compressed-air-actuated piston 43. Compressed air is attached to connections 44 and 45 to operate the double-acting disc-piston 43 that is slidably supported in a cylinder 44. After each stripping process, the tin-shell 14 is pushed with certainty below the level of the bottom edge of the stripper 35. After release, the release plate 41 returns immediately to its rest position. The rest plate 41 may also include a positive conical projection located on its face opposite the mouth of the tin-shell 14. This will achieve a uniform installation of the release plate 41. A lobe 46 projecting far above the top of the mouth of the can is seized by the annular release plate 41 with certainty and moved downwardly during the stripping operation.

The release plate 41 is adjustable in height and serves only to act on the tin-shell 14 after it has been stripped from punch 1. Plate 41 acts in the last instant of the stripping process to insure the subsequent conveyance of the tin-shell 14 in the direction of arrow A. The bottom oblique faces of the stripper fillet 37 effect the actual stripping of the tin-shell 114 from the punch 1. Fillets 37 are laid against the inner surface of the mouth of the tin-shell 14 over a large area.

Stripper fillets 37 are arranged symmetrically around the periphery of the stripper 35. Consequently, the stripping force is uniformly distributed at the circumference of the mouth of the tin-shell 14 thereby largely excluding an undesirable distortion of the tin-shell 14.

Referring again to FIG. 1, pre-stripper 4 acts under the influence of the spring 6 and compressed air fed through bore 7. This pre-stripping effectuates a loosening of the workpiece from the punch in a manner that is known.

While the embodiments have been described hereinabove to the process for stripping of a tin-shell of steel, it is expressly noted that any type of metal container may be stripped from a punch member. The metal may have any type of cross-section and may be manufactured from other metals or metal alloys, for example, aluminum or brass.

While the mechanism for stripping a drawn container from the punch of a deforming tool has been shown and described in detail, it is obvious that this invention is not to be considered as being limited to the exact form disclosed, and that changes in detail and construction may be made therein within the scope of the invention, without departing from the spirit thereof.

I claim:

1. In a mechanism for forming and stripping a container having a mouth wherein the container is formed on a punch during the inserting portion of a deformation stroke through a deforming die and stripped from the punch during the withdrawing portion of the deformation stroke, the combination comprising:

a. an annular stripper member located ahead of the deforming die and disposed around and in a zone of movement during the deformation stroke,

b. said stripper member being effective to strip the container from the punch during said withdrawing portion of the deformation stroke, and

c. beveled means adapted to act upon the peripheral edge of the mouth against a peripheral edge section of the deforming die to form a conically shaped widened portion along said peripheral edge of the mouth,

d. said beveled means being effective to form said conically shaped widened portion toward the end of the inserting portion of the deformation stroke,

e. said stripper member including a stripper surface disposed obliquely with respect to the axis of the punch,

f. said stripper surface being effective to abut said widened portion on the withdrawing portion of the stroke causing the container to be removed from the punch.

2. The combination as defined in claim 1 wherein said stripper member is movably supported on the punch which includes a striker means for carrying the stripper member forwardly to the peripheral edge of the deforming die during said inserting portion of the deformation stroke,

a stationary holder is located ahead of said deforming die to maintain the stripper member stationary during the withdrawing portion of said stroke.

3. The combination as defined in claim 2 wherein said stationary holder comprises a ring concentrically surrounding the punch and said striker means comprises an annular shoulder disposed around the periphery of the punch.

4. The combination as defined in claim 1 wherein said stripper member is movably supported on the punch and said beveled means also constitutes said stripper surface and is located on the movable stripper memher.

5. A mechanism for forming and stripping a container having a mouth, comprising:

a. a deforming die and a punch means which cooperates with a die for forming a container,

b. said punch means being movable through a deformation stroke having an inserting portion and a withdrawing portion,

c. a movably mounted stripper means located ahead of the deforming die and being effective to strip the container from the punch during the withdrawing portion of the deformation stroke, and

d. said stripper means including a stripper member and a means for holding the stripper member stationary at a location laterally displaced ahead of the deforming die,

e. beveled means located on the stripper member for abutting the peripheral edge of the container mouth against a peripheral edge section of the deforming die,

f. said beveled means being effective to form a conically shaped widened portion along said peripheral edge of the mouth toward the end of the inserting portion of the deformation stroke,

g. said beveled means further being effective to abut said conically shaped widened portion during the withdrawing portion of the deformation stroke causing the container to be removed from the punch while the stripper member is stationary.

6. A mechanism defined in claim 5 wherein said stripper member comprises a sleeve having a bottom edge surface tapered downwardly with respect to the direction of movement and facing the die,

said bottom edge surface constituting both a stripper surface and Widener member,

said sleeve being held onto the periphery of the punch surface by adherent members.

7. A mechanism as defined in claim 6, wherein said adherent members comprise at least one friction ring disposed in the top section of said sleeve.

8. A mechanism as defined in claim 6 wherein said adherent members comprised at least one permanent magnet disposed of the holding means for maintaining the sleeve within said holding means.

9. A mechanism as defined in claim 6 wherein said holding means includes a holder member having a bore in the shape of a trap-bush supported concentrically with respect to the axis of the punch means,

said trap-bush having an annular flange pointing radially toward the axis of the punch at the upper face thereof,

the outer surface of said sleeve having the shape of a trap-bush at least in its upper half tapered in a direction conically upwards to fit within the bore of said holder.

10. A mechanism as defined in claim 6 wherein said sleeve is cylindrical and has a row of lined bores disposed in parallel relationship with respect to each other and the axis of the punch and being open at the bottom thereof,

said bores containing spring-loaded thruster members slidably supported to move vertically between two end positions.

11. A mechanism as defined in claim 10 wherein the thruster members have the shape of cylindrical pins and include lugs which project radially outwardly at the bottom of said pins.

12. A mechanism for forming and stripping a container having a mouth, comprising:

a. a deforming die and a punch means which cooperates with the die for forming a container,

c. stationary stripper means located ahead of the deforming die and being effective to strip the container from the punch during the withdrawing portion of the deformation stroke, and

cl. beveled means located on the punch means for abutting the peripheral edge of the container mouth against a peripheral edge section of the deforming die,

c. said beveled means being effective to form a conically shaped widened portion along said peripheral edge of the mouth toward the end of the inserting portion of the deformation stroke,

f. said stripper means including a stripper surface effective to abut said conically shaped widened portion during the withdrawing portion of the deformation stroke causing the container to be removed from the punch.

13. A mechanism as defined in claim 12 wherein said stripper means includes an annular sleeve which surrounds the punch means in the zone of move- I ment for the punch means.

14. A mechanism as defined in claim 13 wherein said sleeve member is fastened to a press frame and includes a roll of stripper fillets which project from the inner wall of the stripper sleeve in the direction of the axis of the punch means in the correspond ingly shaped longitudinal grooves located in the peripheral outer surface of the punch means.

said longitudinal grooves running parallel with re spect to each other and the axis of the punch means, and

said fillets including bottom faces which exhibit a bevel which corresponds with the required angle of widening of the conically shaped mouth of the container.

15. A mechanism as defined in claim 14 wherein said stripper sleeve includes a blind bore open at the bottom thereof between every two adjacent strip per fillets,

each bore receiving a spring-loaded thruster which is movable between two end positions.

16. A mechanism as defined in claim 15 wherein said thrusters have the shape of circular-cylindrical pins having lugs projecting toward the peripheral outer surface of the punch means at the bottom ends thereof.

17. A mechanism defined in claim 12 wherein a release plate means encloses the bottom end section of the stripper sleeve,

said release plate being coupled to an actuating mechanism,

said actuating mechanism being effective to control the release plate in an up-and-down movement in response to the working cycle of the punch means.

18. A mechanism as defined in claim 17 wherein said actuating mechanism comprises a double-acting, pneumatically controlled piston cylinder assembly.

Claims

1. In a mechanism for forming and stripping a container having a mouth wherein the container is formed on a punch during the inserting portion of a deformation stroke through a deforming die and stripped from the punch during the withdrawing portion of the deformation stroke, the combination comprising: a. an annular stripper member located ahead of the deforming die and disposed around and in a zone of movement during the deformation stroke, b. said stripper member being effective to strip the container from the punch during said withdrawing portion of the deformation stroke, and c. beveled means adapted to act upon the peripheral edge of the mouth against a peripheral edge section of the deforming die to form a conically shaped widened portion along said peripheral edge of the mouth, d. said beveled means being effective to form said conically shaped widened portion toward the end of the inserting portion of the deformation stroke, e. said stripper member including a stripper surface disposed obliquely with respect to the axis of the punch, f. said stripper surface being effective to abut said widened portion on the withdrawing portion of the stroke causing the container to be removed from the punch.

2. The combination as defined in claim 1 wherein said stripper member is movably supported on the punch which includes a striker means for carrying the stripper member forwardly to the peripheral edge of the deforming die during said inserting portion of the deformation stroke, a stationary holder is located ahead of said deforming die to maintain the stripper member stationary during the withdrawing portion of said stroke.

4. The combination as defined in claim 1 wherein said stripper member is movably supported on the punch and said beveled means also constitutes said stripper surface and is located on the movable stripper member.

5. A mechanism for forming and stripping a container having a mouth, comprising: a. a deforming die and a punch means which cooperates with a die for forming a container, b. said punch means being movable through a deformation stroke having an inserting portion and a withdrawing portion, c. a moVably mounted stripper means located ahead of the deforming die and being effective to strip the container from the punch during the withdrawing portion of the deformation stroke, and d. said stripper means including a stripper member and a means for holding the stripper member stationary at a location laterally displaced ahead of the deforming die, e. beveled means located on the stripper member for abutting the peripheral edge of the container mouth against a peripheral edge section of the deforming die, f. said beveled means being effective to form a conically shaped widened portion along said peripheral edge of the mouth toward the end of the inserting portion of the deformation stroke, g. said beveled means further being effective to abut said conically shaped widened portion during the withdrawing portion of the deformation stroke causing the container to be removed from the punch while the stripper member is stationary.

6. A mechanism as defined in claim 5 wherein said stripper member comprises a sleeve having a bottom edge surface tapered downwardly with respect to the direction of movement and facing the die, said bottom edge surface constituting both a stripper surface and widener member, said sleeve being held onto the periphery of the punch surface by adherent members.

9. A mechanism as defined in claim 6 wherein said holding means includes a holder member having a bore in the shape of a trap-bush supported concentrically with respect to the axis of the punch means, said trap-bush having an annular flange pointing radially toward the axis of the punch at the upper face thereof, the outer surface of said sleeve having the shape of a trap-bush at least in its upper half tapered in a direction conically upwards to fit within the bore of said holder.

10. A mechanism as defined in claim 6 wherein said sleeve is cylindrical and has a row of lined bores disposed in parallel relationship with respect to each other and the axis of the punch and being open at the bottom thereof, said bores containing spring-loaded thruster members slidably supported to move vertically between two end positions.

12. A mechanism for forming and stripping a container having a mouth, comprising: a. a deforming die and a punch means which cooperates with the die for forming a container, b. said punch means being movable through a deformation stroke having an inserting portion and a withdrawing portion, c. stationary stripper means located ahead of the deforming die and being effective to strip the container from the punch during the withdrawing portion of the deformation stroke, and d. beveled means located on the punch means for abutting the peripheral edge of the container mouth against a peripheral edge section of the deforming die, e. said beveled means being effective to form a conically shaped widened portion along said peripheral edge of the mouth toward the end of the inserting portion of the deformation stroke, f. said stripper means including a stripper surface effective to abut said conically shaped widened portion during the withdrawing portion of the deformation stroke causing the container to be removed from the punch.

13. A mechanism as defined in claim 12 wherein said stripper means includes an annular sleeve which surrounds the punch means in the zone of movement for the punch means.

14. A mechanism as defined in claim 13 wherEin said sleeve member is fastened to a press frame and includes a roll of stripper fillets which project from the inner wall of the stripper sleeve in the direction of the axis of the punch means in the correspondingly shaped longitudinal grooves located in the peripheral outer surface of the punch means, said longitudinal grooves running parallel with respect to each other and the axis of the punch means, and said fillets including bottom faces which exhibit a bevel which corresponds with the required angle of widening of the conically shaped mouth of the container.

15. A mechanism as defined in claim 14 wherein said stripper sleeve includes a blind bore open at the bottom thereof between every two adjacent stripper fillets, each bore receiving a spring-loaded thruster which is movable between two end positions.

17. A mechanism as defined in claim 12 wherein a release plate means encloses the bottom end section of the stripper sleeve, said release plate being coupled to an actuating mechanism, said actuating mechanism being effective to control the release plate in an up-and-down movement in response to the working cycle of the punch means.