US2678694A - Punching machine - Google Patents

Description

H. HOMANN PUNCHING MACHINE May 18, 1954 3 Sheets-Sheet 1 Filed April 10 1951 Illl) I w Illlllll H INVENTOR. I 1% 072mm ETD/766"" ay 18, 1954 H. HOMANN 2,678,694

PUNCI-IING MACHINE Filed April 10, 1951 5 Sheets-Sheet 2 dif 3 Sheets-Sheet 3 Filed April 10, 1951 m n a v w ooooooo a ZNVENTOR. W

Patented May 18, 1954 lJNl STATS ATENT ()FFICE Claims priority, application Germany June 30, 1950 3 Claims. (Cl. 164-86) This invention provides an improved punching machine, more specifically a machine enabling any large number of holes to be pierced by means of a gang of tools each partaking of the nature of both a punch and a drill.

The work is moved against the punches in the manner usual in punching, but each tool is rotated after the iashicn of an Archimedean drill, with the result that it cuts into the work on the working and return strokes. Each tool may, therefore, be designated as a twist punch, and the machine embodying several or a large number of such individual tools, as a twist-punching machine.

The invention enables the task to be performed, of making several or a large number of holes in stampings or pressed pieces of fibrous material such as felted textile or wood fibres, or glass filaments. The improved machine is furthermore well adapted for piercing holes in highly-elastic substances such as sponge rubber, sheet rubber, bandage material (surgical gauze) and expanded plastic. Both through and blind holes can be made with equal facility. Since in large-scale perforating by means of the machine, the holes are usually arranged in regular, geometrical forms, the action of the machine may also be termed panel-perforating of through or blind holes, or a combination of both.

Stampings or pressed pieces of fibrous materials are dificultly drilled or punched since all except completely smooth tools speedily become choked with fibre cuttings and are then useless. The cutting edge of the tool must also be completely smooth. The head of each tool of the machine according to the invention presents an internally and externally smooth cone tapering downward and having a circular cutting edge as well as an ejector aperture for the punched core immediately above this cone. The tool shank is developed in the manner of a spiral or Archimedean drill. All the nuts for effecting the twisting motion are combined in a twist plate. At the head each twist punch is supported on a headbearihg ball; at the foot in a ball-bearing. The

:twist plate moves up and down the thus rotatable but axiall immovable twist punches, which rotate through the same distance in both directions. The work is meanwhile fed up to the punches,

which are thus pressed into the material. The

circular cutting edges thus pierce the work vertically, giving a sharply-defined cut. The conical outer shell expands the out part of the hole and presses the ing well. Even, if filaments have not been cut out fibre ends back into the remainthrough in the rotation of the tool in the one direction, and tend to twist, they will be untwisted by the ensuing reversed rotation, and cut off. The punched cores travel up inside the tool head, with liberty to expand progressively therein, and presently fall out of the wide slot above the tapered portion of the head.

It is thus possible with the improved machine to perforate large felt sheets, wood-fibre sheets,- bandage and dressing materials of textile or plastic substances to any required extent in mass production; also expanded rubber, sheet rubber, sponge rubber, and other difficultly-perforated materials. In all cases, regular panels or periorated areas are obtained, with sharply-defined perforations. The perforations may also be partial, or blind holes, having exactly rectangular bottom profile and a cleanly-removed core.

It follows that the machine enables difficult operations to be performed in a particularly simple manner. The circular form of the punch not only has the advantage that it does not become choked with fibres, but also that the tool is rotatable equally in either direction within the hole. and the power required is exceptionally low. The regular form and low power also enable the machine to be constructed in very large sizes, so that textile or wood fibre felt sheets, glass-filament felts, etc., of appreciably large dimensions can be regularly and accurately perforated in a very short time and in a single operation, with through or blind holes. These through or blind perforated areas have in their turn the advantage of considerably enhancing the utility of the products thus treated, and making them available for new uses and applications. Blind perfcrations have the effect of lightening the product, and materially improving its adhesion to foundations or backings. Sound and heat insulating properties are improved. Such materials are made more suitable for filtering purposes, or -for use as bandages or dressings for instance.

The accompanying drawings show one example of a twist-punching machine in accordance with of the drawings is a front view of the Fig. is a plan of the twist plate of the machine.

Fig. 6 shows the twist plate in side elevation.

Figure 6A shows the twist plate in fragmentary end elevation.

Fig. '7 is a plan of the base plate of the machine.

Fig. 8 is a part sectional side view of the base plate.

Referring first particularly to Figs. 1, 2 and 3, numeral I denotes the machine frame in and on which the actual punching mechanism is ar ranged. Two vertical columns 2, 3 extend upwards from a base plate 8 and guide a screw-nut carrier 4 to the underside of which a twist plate 5 is attached. Between the two columns 2, 3 is a cross-bar 6 to which is attached an upper bear ing plate 1. This bearing plate I and the base plate 8, supported on the top of the machine frame I, carry a number of twist spindles 9 arranged in holes in the plates in such manner as to be rotatable but immovable longitudinally. The crossbar 5 joining the upper end of the two columns 2, 3 carries two plummer blocks ID, i l in which is journalled a horizontal eccentric shaft 12 having at its ends two eccentric discs l3, It. The eccentric pins IE, it of the eccentric discs i3, M drive two connecting rods ll, I8, the lower ends of which work on trunnions i9, 26 of the screwnut carrier at. Below the base-plate 8 a platen 2! for the work is arranged in the machine frame I in such manner as to be vertically movable in either direction by a ram 22 working in a long, cylindrical guide sleeve 23. The lower end of the ram 22 is provided with a cam roller 2d running on a cam 25. Th cam 25 is carried on a horizontal shaft supported in two bearings 26, 21'. The ends of the last mentioned shaft project beyond these bearings 26, 21 and respectively carry a belt pulley 28, and a cam 29 connected with a control mechanism. This control mechanism consists of a vertically guided and elastically supported layshaft 35, having at its lower end a cam roller 3! engaging the cam 29. The upper end of the layshaft 3c is connected with a system of levers 32 associated with one or more stops 33 which pass through the platen 2 I.

As will be apparent from Fig. 4, the spindles 9 are actuated by screw-nuts 53 working over their helically-flutecl parts, said nut; being held in the twist plate 5. Each spindle 9 is retained axially between the base plate 8, and the cross-bar 6. The upper journal 3'! of each spindle 9 works in a bearing bush or guide bearing 38 in the cross-bar 6 and presses against a pivot bearing ball 39 held by a set screw 59 secured by a lock-nut 5!. At the lower end each spindle d is supported by its cylindrical shoulder M in a thrust type ball-bearing 43 and is guided by a further cylindrical shank 44 in a guide bush in the base plate 8. The actual punches or cutters 45 are attached to the lower ends of the spindles 9.

From Figs. 5 and 6 can be seen that the screwnut carrier 6 is provided with two substantial side members ll, 58 having holes 49, 5D to fit the guide columns 2, 3, and with the trunnions I9, 20 to which the connecting rods ll, 18 are linked. The actual twist plate 5, with the necessary number of holes, is attached to the underside of the carrier Figs. 7 and 8 show the base plate 8 in detail. The central portion of this base plate is perforated to receive the spindles 9. References 5|, 52 denote bearing sockets on the base plate for the guide columns 2, 3,

The action of the described machine will be readily understood. The drive 36 shown at the top of Fig. 2 rotates the eccentric shaft I2 with the eccentric discs 13, I4 and reciprocates, through the intermediary of the eccentric pins :5, iii, connecting rods 17, i8 and trunnions I9, 25, the screw-nut carrier 5 with the attached twist plate 5. This causes the screw nuts 53 (Fig. 4) likewise to rise or fall and thereby rotate the spindles 9, which are prevented from moving longitudinally, in such manner that the said spindles together with the punches or cutters 46 attached to their lower ends, are rotated in the one or the other direction, respectively, during such upward or downward motion. The spindles do not, therefore. themselves move vertically, but merely rotate in either direction according to the upward or downward motion of the carrier 4 and attached twist plate 5.

The transmission elements 34, 35 shown in Fig. 2, rotate the cam 25, which lifts the cam roller 24 on the ram 22, and consequently raises the ram and the attached platen 2! (Fig. 1). The cam 29, which is on the same shaft as the cam 25, actuates the control mechanism 3B, 3!, 32, the setting of the cam being specifically such that the stop or steps 33 rises or rise through the platen 2! when a new work-piece is inserted or fed forward. This takes place always when the platen i lowered, i. e. when the cam 25 has not raised the ram 22 and platen 2 i.

The cycle of operations of a twist-punching machine according to the invention develops in such manner that (a) a work-piece, e. g. a felt or wood-fibre sheet is fed forward until it abuts against the stop or stops 33, (b) it is lifted by the successive action of the cam 25, roller 24, ram 22 and platen 2i against the punches or cutters 45, while the spindles 9 rotate in such manner that the lower cutting edge of each punch 46 (Fig. 4) cuts into the material, (0) the platen 2| then descends after the roller 24 has run off the cam hump of the cam 25, while the spindles, reversing their direction of rotation, withdraw from the hole with a cutting action, carrying along the core punched out of the material, and finally (d) the stop or stops 33 actuated by the control mechanism 29, 30, 3|, 32, drops and the work-piece can be fed forward or ejected. The next work-piece when fed forward abuts against the meanwhile raised stop or stops 33 and is thus ready for the next punch stroke. The punched cores drop automatically out of the slot 54 in the bore of each punch by the pressure of the following core or cores.

I claim:

1. A machine for recessing holes into a thick, elastic work piece, comprising a group of vertical, horizontally rotatable, vertically immovable spindles closely adjacent one another, each spindle having a smooth, downwardly tapering bottom piece with a sharp, annular knife edge at the bottom end and with a vertical, upwardly expanding channel extending through the bottom piece, each spindle also having a spirally fluted surface above the bottom end and having a discharge opening for the channel below the fluted surface; a rigid, vertically reciprocable plate having threaded holes distributed over its area and mating with the fluted surfaces of the spindles; a vertically reciprocable work table to support the work piece below the bottom ends of the spindles; and means to vertically, conjointly reciprocate the plate and work table so that alternately (1) the work table rises against the spindles while the spindles rotate in one direction cutting into the work piece, and then (2) the work table descends while the spindles rotate in the opposite direction, severing the cores from the work piece.

2. A machine as described in claim 1 wherein the means to vertically reciprocate the work table comprises a cam of such configuration that the work table descends a major part of its total ver- 10 tical stroke during an initial and minor part of the period when the spindles rotate in said opposite direction, whereby the severing of the cores is facilitated.

3. A machine as described in claim 1, additionally comprising means to control horizontal movements of the work piece onto and from the work table, conjointly with predetermined phases of the vertical reciprocation of the work table.

References Cited in the file of this patent UNITED STATES PATENTS Number Name Date Re. 20,483 Lewis et a1 Aug. 24, 1937 76,970 Anzus Apr. 21, 1868 807,672 Gros Dec. 19, 1905 1,347,214 Dom July 20, 1920 2,214,666 Elf et al. Sept. 10, 1940

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