US2722275A - Machines for feeding strips of thin material - Google Patents

Description

Nov. l, 1955 l.. G. FoRsTER MACHINES FOR F'EEDING STRIPS OF' THIN MATERIAL Original Filed March 2l, 1949 a -Lignusi R m W07 m www NOV 1, 1955 G. FoRsTER 2,722,275

MACHINES FOR FEEDING STRIPS OF' THIN MATERIAL Original Filed March 2l, 1949 4 Sheets-Sheet 2 87 1:2' 26]/ il? y 46 a 2. a IN ENTO? BY u lb ATTOPNE Nov. 1, 1955 G. FoRsTER MACHINES FOR FEEDING STRIPS oF THIN MATERIAL 4 Sheets-Sheet 5 Original Filed March 21. 1949 /NvENToR 4141 glug.. gruv Bm Mv M ATTORNEY@ Nov. 1, 1955 l.. G. FoRsTER MACHINES FOR FEEDING STRIPS OF TH'IN MATERIAL 4 Sheets-Shea?I 4 Original Filed March 21, 1949 INVENTOR M 90u59 .M2 mii United States Patent Office 2,722,275 Patented Nov. 1, 1955 MACHINES FOR FEEDING STRIPS OF THIN MATERIAL Leslie Gordon Forster, Ealing, London, England, assigner to Forsters Machine Company Limited, Hayes, England, a corporation of Great Britain Original application March 21, 1949, Serial No. 82,577, now Patent No. 2,586,462, dated February 19, 1952. Divided and this application December 17, 1951, Serial No. 262,126

Claims priority, application Great Britain December 15, 194.8

7 Claims. (cl. 16a-6s) This invention relates to a machine for cutting lengths from a long strip or roll of thin material such as paper, cellulose or the like, and refers generally to the arrangement, association and construction of several components for feeding the strip forward towards the cutting elements.

The apparatus is comparatively light and compact and may be supported adjustably above a base, the severed lengths of material being of use in connection with other operations to be carried out by apparatus supported by the base.

Apart from the general arrangement and association of the various components, the machine includes a rotating cutter associated with and co-operating with a reciprocating cutter.

This machine may, for example, be used to supply measured lengths of strip material for wrapping packages, the wrapping or conveyor or other mechanism being arranged on the base below the machine. It is, however, to be understood that the application of this machine for cutting off lengths of material is not limited to such an application.

It is an object of the invention to provide a machine of this type which is compact and light and is capable of rapid operation.

It is also an object of, the invention so to mount a feed roller assembly that it may be readily removed and replaced by another of different diameter without necessirating any alteration or adjustment of the mechanism.

It is a further object of the invention to support the driving feed roller in a readily removable manner in a displaceable frame which is so mounted that it may pivot about the axis of the rotational cutter.

It is another object of the invention to provide means for holding the displaceable frame in its operative position.

It is a Still further object of the invention to pass the material between fixed and pivotally mounted guiding plates provided with openings permitting the effective surfaces of the driving feed roller and of an idle or a friction driven roller to engage the material.

This is a division of my copending application, Serial Number 82,577, tiled March 21, 1949, now Patent No. 2,5 86,462, issued February 19, 1952.

In the embodiment of the invention shown by way of example in the accompanying drawings:

Figure l shows a front elevation;

Figure 2 shows a plan;

Figure 3 shows a section on the line 3--3 of Figure 1;

Figure 4 is an outside side view showing the gearing in chain lines;

Figure 5 is a section on the line 5 5 of Figure l;

Figure 6 is a part section on the line 6 6 of Figure 2;

Figure 7 is a perspective view showing the main frame of the apparatus and parts supported thereby;

Figure 8 is a perspective view of a pivoted displaceable frame carrying the driving roller;

Figure 9 is a perspective view of a swinging frame carrying the movable cutter; and

Figure 10 is a detail connected with the pivoted displaceable frame carrying the driving roller.

The main frame comprises two side members 20 carrying bearings for most of the rotating shafts, a front transverse bar 21 and a back transverse plate 22. All these components may be made separately and welded together or some only may be so built up; the front transverse bar 21, for example, is shown bolted to the forward ends of the side members 20. Alternatively, all or most of the parts may be formed as a single casting of steel or other material.

The main frame is located above a base 1 in one or more parts and is supported by a vertical framework 2 from one or both of said parts. The main frame may be carried by an overhung extension 2a, as shown, or by a bridge member, the supporting means consisting of vertical guides 3 with a supporting and adjusting screw 4. The vertical guides 3 comprise, in the example shown, two parallel dove-tail guides receiving corresponding member 3a secured to the back plate 22 of the main frame. The adjusting screw is mounted in upper and lower bearings or brackets 5 on the extension 2a and engage a nut, not shown, on the main frame. A hand wheel 7 rotates screw 4 to raise or lower the main frame and a pointer 7a on the main frame moving over a scale 7b on extension 2a facilitates vertical adjustment.

Secured on the upper part of the main frame is a cross piece 23 forming a support for a metal plate which constitutes the xed guide member 10 for the strip 8, the strip being led between the xed guide plate 10 and a movable guide plate 11.

Towards the forward end of the frame, the bearings for driving shaft 25 carrying the rotating cutter 26 are mounted. This shaft at one end carries a gear wheel 27 and at the other end a knurled disc 2S for facilitating hand rotation for adjustment. The intermediate part of shaft 25 is shown of square section and to this section is clamped, by suitable means such as set bolts 29, the rotating cutter 26. The effective radius of the cutting edge may be adjusted by screws 37, one towards each end of the cutter. The cutter rotates in an anti-clockwise direction, as viewed in Figures 3 and 5.

A friction-driven roller having a central strip engaging member 3d and end friction-driven members 30a and forming one element of the strip feeding mechanism is mounted on a spindle 31 supported by the side members 20 of the main frame. Members 30, 30a co-operate with cir cular rubber elements 52, 53 secured to a tube 54 mounted on a driving shaft 47 the assembly forming the other gear driven element of the strip feeding mechanism, as will be described hereinafter.

Mounted in the side members 20 is a shaft 33 having secured thereon at one end a gear wheel 34 and carrying at some intermediate point preferably at or towards the middle of its length, an eccentric 35 on which is mounted a radial ball bearing 36, this ball bearing being used in connection with the operation of a movable cutter mounted on a movable frame as will be described hereinafter.

A displaceable frame carrying the rotatable driving feed roller is displaceable from the operative position in which it engages the friction-driven feed roller and s pivotally mounted, as shown in the present embodiment, so as to rotate or rock about the axis of the rotating cutter. The displaceable frame comprises two side members 40 rigidly connected by a cross bar 41 and pivotally supported on the outer end portions of the bushes in which the rotating cutter driving shaft 25 rotates. The bushes are fixed in but extend outside the main frame side members 20. The displaceable frame is biased towards its operative position by resilient tension elements 42 connected between brackets 43 on the edges of the side plates 40 of the displaceable frame and pins 44 on the main frame. These tension elements may conveniently consist of tension or compression springs in telescopic tubes.

The displaceable frame may be pulled backwards from its operative position against the resistance of the resilient element 42 by a curved plate 45 fixed on the cross bar 41, and when so withdrawn may be retained in position by a spring-controlled pin 46, shown also in Figure 10, carried on one of the side members 40 of the displaceable frame and engaging a hole or recess in the corresponding side member 20 of the main frame.

The sides 40 of the frame are provided with open-ended slots or recesses 49 (see Figures 5 and 8) which serve for the support of the bearings of the driving roller shaft 47. The shaft is conveniently supported by ball bearings 50, each bearing entering the wider part of its slot. The outer race of the bearing engages the shoulder formed by the part of the slot of lesser width to prevent end movement, this narrower part of the slot being, however, of suicient width to allow the passage of the outer ends of the shaft r of distance pieces thereon. The bearings 50 are held in position in the semi-circular ends of the slots by the resilient elements 42 when the displaceable frame is in the operative position with the engaging surfaces of the driving roller engaging the idle roller.

The engaging surfaces of the driving roller consist as mentioned previously of circular ring elements 52, 53 which may be of rubber bonded or otherwise secured to a tube 54 mounted on but spaced from shaft 47 by short sleeves at the ends. The shaft 47 as shown consists of a long bolt having at one end a head 48 and at the other end a nut 51, whereby the tube 54, the inner races of the ball bearings, a driving gear wheel 55 and distance pieces are clamped together. The end elements 52 engage the end engaging members 30a on the non-driven roller towards the ends so as to be clear of both the guide plates 10, 11 and the strip 8 which is being fed between the rollers. The centre rubber element 53 and the central engaging member 30 grip the strip 8 between them. To assist in obtaining satisfactory operation, the two end elements 52 are of slightly greater diameter than the central element 53, a difference of two thousandths of an inch diameter being usually suicient allowance for the thickness of the strip. This feature is of special value in connection with hard surfaced material such as cellulose film. The engaging members on the non-driven roller may be of rubber or metal, or a continuous rubber or metal roller may be employed. It is to be understood that the term rubber includes all materials having similar resilient characteristics such as synthetic rubber compounds.

The driving roller shaft 47 at one end carries, and is driven by, the gear wheel 55 which is geared to the gear wheel 27 on the rotating cutter shaft 25 through an idle wheel 56 rotatably mounted on a spindle secured in one of the side members 40 of the displaceable frame.

It will be seen that the displaceable frame may be readily withdrawn from its operative position against the resistance of the resilient elements 42, the roller assembly being then removed and replaced by a similar assembly which may be identical in all respects with the exception of the diameter of the rubber elements 52, 53. In this way the machine may be rapidly adjusted so as to cut off any required length from the strip.

When the displaceable frame has been withdrawn the movable guide plate 11 may be swung clear, as shown in Figure 5. The plate 11 is carried by bars 58 pivoted at 59 to members 60 secured by set bolts 61 tothe cross piece 23 extending between the side members 20 of the main frame. The set bolts 61 pass through slots 60a in members 60 whereby the gap between the guide plates 10 and 11 may be finely adjusted according to the thickness of the material of the strip so as to give minimum clearance and thus guide the strip substantially in a predetermined path.

To enable the central ring element 53 on the driving roller to co-operate with the engaging member 30 on the non-driven roller, openings 62, 63 with bevelled edges are cut in the fixed and movable guide plates 10, 11 respectively.

In the present embodiment, the frame carrying the movable cutter 66 is shown specially in Figures 3, 5 and 9 and comprises two end plates 67, a base member 68, and a vertical bracket 69 of T section having an extension 70 at the top integral therewith. All these elements may be bolted together or joined by welding or the frame may be a metal casting.

The movable cutter has imparted thereto a cycle of movement in a predetermined path. In the embodiment shown herein, the movable cutter is mounted on a swinging frame so that it moves in an arc of a circle, the swinging frame being mounted on a pivoted transverse shaft 7l carried in the side members 20 of the main frame. The movable cutter 66 is secured firmly by countersunk set screws 72 to the end plates 67 and to one or more upward extensions 73 of the base member 68 and is located against downward movement by registering with or engaging the upper edge of the front part of member 68. This is shown on Figures 4 and 6. Springs 74 bias the swinging frame so that the movable cutter 66 tends to move towards the rotating cutter 26. This movement is limited, however, by an adjustable stop 76 introduced between the extension 70 at the upper end of the T section bracket 69 forming part of the swinging frame and the back plate 22 of the main frame. Springs 74 engage between base 68 and stops 78 carried by adjusting screws 79.

The swinging frame is held in its retracted position against the force exerted by the spring 74 during the greater part of the rotation of the rotating cutter 26. This retracting means comprises an eccentric 35 located at or about the centre of shaft 33 which is carried in bearings in the side members 20 of the main frame. On the eccentric is mounted the inner race of the radial ball bearing 36, the race being a force tit on the eccentric. The outer race is adapted to engage an adjustable operating element carried on the vertical T-section member 69 of the swinging frame. This adjustable element, as shown, consists of a bolt 86 screwed into a boss forming part of the T-section member 69 and locked in position by a lock nut 87. The eccentric mechanism co-operating with this adjustable bolt 86 holds the swinging frame in a position such that the movable cutter 66 is held clear of the rotating cutter 26 except for a short interval during which the cutting edge of the rotating cutter 26 moves past and engages the cutting edge of the movable cutter 66.

The shaft 33 is shown geared to the driving shaft 25 in a 2 to l ratio by the gears 27, 34 so that the rotating cutter 26 operates only during alternate revolutions. The rotating cutter is geared to the driving roller shaft 47 in a l to l ratio so that the length of strip cut off for each cycle of operations is equal to twice the circumference of the ring element 53 on the driving roller.

It is obvious that the driving shaft 25 and the shaft 33 may be geared to rotate at the same speed, or that the driving shaft may rotate at some other multiple or submultiple of the speed of the shaft 33. The multiple iigures are not limited to integer values but include any ratios between the number of rotations of the rotatable cutter and the number of cycles of movement of the movable cutter during the periods between coincidence of the two cutting edges. For example, if the ratio were 2.5, the rotating cutter would rotate ve times between cuts and the movable cutter would move through two cycles.

When the driving roller of smallest diameter is in use, gear wheels 55, 34 on the ends of the driving roller shaft 47 and the eccentric shaft 35 respectively will mesh with one another. This is not essential for operation but inci` dentally enables the machine to be made as compact as possible. The introduction of the idle gear wheel 56 between gear wheels 27, 55 ensures correct direction of rotation.

Extreme variations of diameter of the feed roller arc made possible by the use of gearing which enables the feed roller to make more than one rotation for each operation of the movable cutter. As an example, in one size of machine driving feed rollers Varying in diameter from 8 to 40 mm. may be rapidly interchanged. The displaceable frame adjusts itself to any size of roller within the limits of the machine so as to ensure engagement between the feed roller in use and the non-driven roller.

Shaft 33 passes through slots 88 in the side walls 67 of the swinging frame, the slots being curved and elongated sufficiently to allow the necessary swinging movement.

I claim:

1. A machine for feeding a strip of thin material a predetermined distance between successive cutting operations comprising; a main frame; a displaceable frame having open ended slots therein; a first driving feed roller rotatably mounted in said slots; a second feed roller mounted in said main frame; a movable cutter; a rotating cutter co-operating with said movable cutter, said cutters being mounted in said main frame; means to maintain both of said frames in position with the first driving feed roller in engagement with said second feed roller; and driving gear means connecting the rotating cutter and said first driving feed roller; whereby any one of a plurality of interchangeably mountable driving feed rollers of different diameters may be readily inserted in said slots of said displaceable frame.

2. A machine for feeding a strip of thin material as claimed in claim 1, comprising in combination therewith; a fixed guide plate for the strip mounted on said main frame; a movable guide plate; the strip engaging surfaces on the first driving roller and the second roller passing through slots in said guide plates; and a support for said movable guide plate pivotally mounted on said main frame, whereby the movable guide plate may be moved clear of the strip when the displaceable frame is withdrawn to disengage the first and second rollers.

3. A machine for feeding a strip of thin material as claimed in claim 2 comprising in combination therewith; means for adjusting the position of the support for said movable guide plate pivotally mounted on said main frame, whereby the width of the space between the guide plates for the passage of the strip may be adjusted.

4. A machine for feeding a strip of thin material as claimed in claim 1, comprising a shaft operating said movable cutter once during each rotation thereof; gearing connecting said rotating cutter and said first driving feed roller, the overall gear ratio being such that the number of rotations of the first driving feed roller between successive cutting operations is greater than unity.

5. A machine for feeding a strip of thin material as claimed in claim 1, comprising a shaft operating said movable cutter once during each rotation thereof; two to one gearing connecting said shaft to said rotating cutter; and one to one gearing connecting the rotating cutter and the first driving feed roller, whereby the said feed roller makes two revolutions between successive cutting operations.

6. A machine for feeding a strip of thin material as claimed in claim 1, comprising pairs of cooperating surfaces on said first and second feed rollers engaging one another beyond the edges of the strip, whereby the second roller may be driven frictionally by the first roller and a pair of cooperating surfaces on said first and second rollers having a gap between them less than the thickness of the strip when the first mentioned pairs of cooperating surfaces are in engagement, whereby the strip of thin material may be gripped between said second mentioned cooperating surfaces.

7. A machine for feeding a strip of thin material as claimed in claim 1, in which each of said two open ended slots is formed of two different widths with a step therebetween and the closed ends of the slots are formed of two concentric stepped semi-circles of diameter respectively equal to the widths of the slots; and bearings on the end of the driving feed rollers disposed in the parts of the slots of larger width, the steps in the two slots facing in opposite directions, thereby preventing endwise movement of the feed roller relatively to the displaceable frame.

References Cited in the file of this patent UNITED STATES PATENTS 1,317,383 Northrup Sept. 30, 1919 1,946,170 Mikaelson Feb. 6, 1934 1,998,931 Kellog Apr. 23, 1935 2,062,737 Aiken Dec. 1, 1936 2,103,264 Lorig Dec. 28,1937 2,180,903 Jensen Nov. 21,1939 2,266,362 Forster Dec. 16, 1941 2,547,375 Chernack Apr. 3,1951 2,548,136 Auer Apr. 10, 1951 2,624,574 Camras Jan. 6,1953

FOREIGN PATENTS 278,459 Great Britain Oct. 13, 1927

Images