US3166460A - Drum loading - Google Patents

Drum loading Download PDF

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Publication number
US3166460A
US3166460A US306532A US30653263A US3166460A US 3166460 A US3166460 A US 3166460A US 306532 A US306532 A US 306532A US 30653263 A US30653263 A US 30653263A US 3166460 A US3166460 A US 3166460A
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Prior art keywords
drum
sheet
tape
edge
supporting
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Expired - Lifetime
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US306532A
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Hoer Kenneth George
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Muirhead and Co Ltd
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Muirhead and Co Ltd
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    • HELECTRICITY
    • H04ELECTRIC COMMUNICATION TECHNIQUE
    • H04NPICTORIAL COMMUNICATION, e.g. TELEVISION
    • H04N1/00Scanning, transmission or reproduction of documents or the like, e.g. facsimile transmission; Details thereof
    • H04N1/04Scanning arrangements, i.e. arrangements for the displacement of active reading or reproducing elements relative to the original or reproducing medium, or vice versa
    • H04N1/06Scanning arrangements, i.e. arrangements for the displacement of active reading or reproducing elements relative to the original or reproducing medium, or vice versa using cylindrical picture-bearing surfaces, i.e. scanning a main-scanning line substantially perpendicular to the axis and lying in a curved cylindrical surface
    • H04N1/08Mechanisms for mounting or holding the sheet around the drum
    • H04N1/083Holding means
    • H04N1/0852Adhesive means
    • HELECTRICITY
    • H04ELECTRIC COMMUNICATION TECHNIQUE
    • H04NPICTORIAL COMMUNICATION, e.g. TELEVISION
    • H04N1/00Scanning, transmission or reproduction of documents or the like, e.g. facsimile transmission; Details thereof
    • H04N1/04Scanning arrangements, i.e. arrangements for the displacement of active reading or reproducing elements relative to the original or reproducing medium, or vice versa
    • H04N1/06Scanning arrangements, i.e. arrangements for the displacement of active reading or reproducing elements relative to the original or reproducing medium, or vice versa using cylindrical picture-bearing surfaces, i.e. scanning a main-scanning line substantially perpendicular to the axis and lying in a curved cylindrical surface
    • H04N1/08Mechanisms for mounting or holding the sheet around the drum

Definitions

  • This invention relates to a method and a mechanism for attaching a thin pliantsheet to the peripheral surface of a drum or cylinder.
  • a method and a mechanism for attaching a thin pliantsheet to the peripheral surface of a drum or cylinder Such an occasion arises, for instance, when it is required to attach the copy material to 'therotatable drum of a facsimile transmitter or the sensitized recording material to a correspondingly rotatable drum of a facsimile receiver.
  • clipping means to secure the two ends of the pliant sheet to the drum.
  • the clips comprise springy steel strips which extend to the length of the drum and clip into registers in the extremities thereof.
  • the invention consists in a mechanism for attaching an edge of a thin pliant sheet to the peripheral surface of a drum comprising means for supporting a strip of adhesive tape across and adjacent to. the drum surface, means for lowering the tape towards the drum surface to overlie the edge of the sheet and the drum surface and means for rolling the strip onto the edge of the sheet and drum surface.
  • FIGURE 1 is a sectional side elevation of the drum loader according to the invention on the line I-I of FIGURE 2;
  • FIGURE 2 is a perspective view
  • FIGURE 3 is an exploded view of the principal working parts
  • FIGURES 4a, b and 0 show selected moving parts in their initial positions
  • FIGURES 5a, b and 0 show the moving parts in their mid-positions.
  • FIGURES 6a, b and c show the moving parts in their final positions.
  • FIGURES l and 2 a part of the table or console which may. take any convenient form is shown at 1.
  • the drum 2 is located in suitable bearings in the loading poistion on the top surface 3 of table 1 as indicated in the drawing.
  • the frame 4 which supports the pliant sheet prior to loading onto the drum 2 is shown in the figures in the raised or operative position.
  • Bracket 5 is rigidly attached to frame 4.
  • Arm 6 is pivoted on bracket 5 at 7 at one end, and on the table 1 at 8 at the other end.
  • Roller 9 (FIGURE 1) rests in a channel in part 10.
  • Latch 11 engages latching pin 12 when frame 4 is in the upward or operating position as shown.
  • Latching pin'12 is an extension of rod 13 which may be actuated for example by a foot pedal (not shown). When latch 12 is released by operating the pedal the frame may be lowered to a position beneath the table 1. This motion is controlled by the passage of roller 9 along the channel part '10 and the course taken by the frame is indicated by broken line X.
  • Broken lines 14 in FIGURE 1 show the position of the frame when fully lowered.
  • Platform or platen 14 is rigidly attached to frame 4 and is provided with a flap 15 hinged at 16.
  • the flap 15 may be raised by a handle 17 and broken lines 15' show the flap in this raised position.
  • the flap is raised to insert the pliant sheet 19 which is held between platen 14 and flap 15 when the latter is lowered.
  • platen 14 and flap 15 may be covered on their mating faces with soft material such as felt or baize as protection for the pliant sheet.
  • soft material such as felt or baize as protection for the pliant sheet.
  • a small sub-frame mounted on the frame 4 and generally indicated at 20 carries the various parts of the attaching device for the pliant sheet. These parts are also shown in the exploded drawing (FIGURE 3). Motion isimparted to the mechanism byhandle 21 which actuates arms 22 pivoted to subframe 20 at b. Arms 23 are pivoted to arm 22 at a and carry roller 24 at their lower end. The roller is of sensibly the same length as the drum.
  • Roller 24 is guided round the periphery of drum 2 over a limited distance by guide plates 25 attached to sub-frame 20.
  • Cam' plate 26 is rigidly attached to left hand arm 23 in the position shown.
  • Bell crank 27 is mounted on rock shaft 31 which is also pivoted at b and carries pin 23' in its upper arm. Pin 23 engages slot 29 in cam plate 26.
  • a tape support arm 30 is attached to the lower arm of bell crank 27 and a similar arm 30a is provided at the right hand side mounted on rock shaft 31.
  • the two support arms 30, 30a are pitched slightly wider apart than the length of the drum.
  • Drum 2 is provided with a latching pin 32 on the left hand end surface which engages one or other of the two notches 33 and 34 in latching lever 35.
  • This latch establishes a controlled loading position to maintain the correct state of dynamic balance when the drum is rotating.
  • latching pin 32 is engaged with notch 33, when the drum 2 has been revolved so that the pliant sheet 19 is wrapped round the drum, pin 32 engages with notch 34.
  • Latching lever 35 is pivoted at b and is spring loaded in the direction of pin 32. It may be disengaged by operating lever 36 attached thereto.
  • a strip of adhesive tape 37 (FIGURE 1) is stretched between the tape support arms 30, 30a at one end of the drum and its counterpart at the other end of the drum.
  • FIGURES 4a, 4b and 4c The positions of the respective parts are indicated in FIGURES 4a, 4b and 4c.
  • the handle 21 is then pulled down.
  • Arm 23 is thus caused to force roller 24 around the cylindrical surface of the drum guided by guides 25.
  • crank 27 is forced along the first part of the three-part slot 29 in the cam plate 26 thus forcing crank 27 to rotate counter clockwise to lower the tape support arms 30, 3ia to a position in which half of the tape width overlies the upper edge of sheet 19 and the other half overlies the cylindrical drum surface directly.
  • the handle which has been moved down in one continuous movement is then released and restores to the position shown in FIGURE 1.
  • the drum 2 is unlatched by depressing lever 36 and the drum 2 is rotated clockwise by hand until pin 32' latches in notch 34 of latching lever 35. During this motion the pliant sheet 19 is progressively wrapped round the drum 2 and pressed into intimate contact therewith by roller 24.
  • a further strip of adhesive tape is then stretched across between the tape supports 30, 30a and the handle 21 is again operated downwards.
  • the tape is applied with half its width overlying the trailing edge of the pliant sheet 19 and half its width overlying the 4. length of tape which is securing the leading edge of the pliant sheet (the trailing edge of the pliant sheet will overlie the half of the first length of tape which is secured directly to the drum) and is rolled out so that it adheres securely.
  • Latch 12 is then released and the frame 4 lowered to the broken line position so that the drum with sheet 19 wrapped securely around it is available for the transmitting or recording process or for unloading or lifting the drum away.
  • a mechanism for attaching an edge of a thin pliant sheet longitudinally across the curved peripheral surf-ace of acylindrical drum comprising means for mounting the drum for rotational movement, means mounted thereon for supporting a strip of adhesive tape longitudinally across and adjacent to the drum surface, cam means engaging said supporting means for lowering the tape towards the drum surface to overlie the edge of the sheet and the drum surface, roller means secured to said cam means for rolling the strip onto the edge of the sheet and drum surface and means pivotally secured to said supporting means for moving said cam means and roller means to effect said tape lowering and rolling operations.
  • cams means comprises means for releasing the supporting means from the strip of the tape.
  • a mechanism as claimed. in claim 1, comprising spring-loaded means pivotally mounted in relation to the supporting means for latching the drum in an indexed position for the attaching operation.
  • a mechanism as claimed in claim 1, comprising spring-loaded means pivotally mounted in relation to the supporting means for latching the drum in two indexed positions rotationally spaced from each other for separate attaching operation for the respective ends of the pliant sheet.

Description

Jan. 19, 1965 K. e. HOER 3,166,460
DRUM LOADING Filed Sept. 4, 1963 4 Sheets-Sheet 1 Jam 1965 K. G. HOER 3,166,460
' DRUM LOADING Filed Sept. 4, 1963 4 Sheets-Sheet 2 Jan. 19, 1965 K. G. HOER 3,166,460
DRUM LOADING Filed Sept. 4, 1963 4 Sheets-Sheet 3 K. G. HOER DRUM LOADING Jan. 19, 1965 4 Sheets-Sheet 4 Filed Sept. 4, 1963 United States Patent M DRUM LOADING Kenneth George Hoer, Beckenham, Kent, England,
assignor to Muirhead and Co. Limited, Kent, England, a British company Filed Sept. 4, 1963, Ser. No. 306,532 Claims priority, application Great Britain, July 31, 1963,
Claims. (Cl. 156-446) This invention relates to a method and a mechanism for attaching a thin pliantsheet to the peripheral surface of a drum or cylinder. Such an occasion arises, for instance, when it is required to attach the copy material to 'therotatable drum of a facsimile transmitter or the sensitized recording material to a correspondingly rotatable drum of a facsimile receiver. In apparatus of this kind where the speed of rotation of the drum is rel atively slow, say of the order of 120 r.p.m., it is known to use clipping means to secure the two ends of the pliant sheet to the drum. In one instance the clips comprise springy steel strips which extend to the length of the drum and clip into registers in the extremities thereof.
However, at high drum speeds of the order of 3000 rpm. the retaining clips cause serious dynamic unbalance which unless countered by a balancing mass, results in serious vibrations. Furthermore, the centrifugal force occasioned by high drum speed is likely to cause the clips to loosen or even to fly off the drum. A
' further disadvantage accompanying the use of clips is the air turbulence they cause tending to produce judder or sudden unevenness in drum speed as they pass the lens or shutter of the scanning means due to changes in air pressure. Also, it may be said that the front working clearance 0f some objective lens mountings is very small and this does not allow sufiicient space for the drum clips to pass.
For the above reasons it has been found convenient to attach the pliant sheet to the drum by means of an adhesive tape which for all practical purposes gives a smooth uninterrupted surface. 7 However, adhesive tape is diificult to apply while, at the same time, maintaining the sheet in close contact with the drum. Even with skilled manipulation the operation takes .a considerable time to perform with very uncertain results.
It is "an object of .the present invention to provide a mechanical loading device which will enable a pliant sheet to be attached to the peripheral surface of a rotatable drum using an adhesive tape to secure each end of the pliant sheet in turn to the drum surface.
It is a further object to enable the loading of the drum to be carried out rapidly and effectively by persons havinglittle-manipulative skill.
The invention consists in a mechanism for attaching an edge of a thin pliant sheet to the peripheral surface of a drum comprising means for supporting a strip of adhesive tape across and adjacent to. the drum surface, means for lowering the tape towards the drum surface to overlie the edge of the sheet and the drum surface and means for rolling the strip onto the edge of the sheet and drum surface.
Conveniently, means are provided for releasing the Bibfififih Patented Jan. 19, 1965 The invention will be described by way of example with reference to the accompanying drawings in which:
FIGURE 1 is a sectional side elevation of the drum loader according to the invention on the line I-I of FIGURE 2;
FIGURE 2 is a perspective view;
FIGURE 3 is an exploded view of the principal working parts;
FIGURES 4a, b and 0 show selected moving parts in their initial positions;
FIGURES 5a, b and 0 show the moving parts in their mid-positions; and
FIGURES 6a, b and c show the moving parts in their final positions.
Referring now to FIGURES l and 2, a part of the table or console which may. take any convenient form is shown at 1. The drum 2 is located in suitable bearings in the loading poistion on the top surface 3 of table 1 as indicated in the drawing. The frame 4 which supports the pliant sheet prior to loading onto the drum 2 is shown in the figures in the raised or operative position. Bracket 5is rigidly attached to frame 4. Arm 6 is pivoted on bracket 5 at 7 at one end, and on the table 1 at 8 at the other end. Roller 9 (FIGURE 1) rests in a channel in part 10. Latch 11 engages latching pin 12 when frame 4 is in the upward or operating position as shown. Latching pin'12 is an extension of rod 13 which may be actuated for example by a foot pedal (not shown). When latch 12 is released by operating the pedal the frame may be lowered to a position beneath the table 1. This motion is controlled by the passage of roller 9 along the channel part '10 and the course taken by the frame is indicated by broken line X. Broken lines 14 in FIGURE 1 show the position of the frame when fully lowered. Platform or platen 14 is rigidly attached to frame 4 and is provided with a flap 15 hinged at 16. The flap 15 may be raised by a handle 17 and broken lines 15' show the flap in this raised position. The flap is raised to insert the pliant sheet 19 which is held between platen 14 and flap 15 when the latter is lowered. Conveniently, platen 14 and flap 15 may be covered on their mating faces with soft material such as felt or baize as protection for the pliant sheet. It will be seen that the parts of the apparatus are so proportioned and disposed that the upper edge of the pliant sheet 19 rests on the surface of drum 2,. A small sub-frame mounted on the frame 4 and generally indicated at 20 carries the various parts of the attaching device for the pliant sheet. These parts are also shown in the exploded drawing (FIGURE 3). Motion isimparted to the mechanism byhandle 21 which actuates arms 22 pivoted to subframe 20 at b. Arms 23 are pivoted to arm 22 at a and carry roller 24 at their lower end. The roller is of sensibly the same length as the drum. Roller 24 is guided round the periphery of drum 2 over a limited distance by guide plates 25 attached to sub-frame 20. Cam' plate 26 is rigidly attached to left hand arm 23 in the position shown. Bell crank 27 is mounted on rock shaft 31 which is also pivoted at b and carries pin 23' in its upper arm. Pin 23 engages slot 29 in cam plate 26. A tape support arm 30 is attached to the lower arm of bell crank 27 and a similar arm 30a is provided at the right hand side mounted on rock shaft 31. The two support arms 30, 30a are pitched slightly wider apart than the length of the drum.
Drum 2 is provided with a latching pin 32 on the left hand end surface which engages one or other of the two notches 33 and 34 in latching lever 35. This latch establishes a controlled loading position to maintain the correct state of dynamic balance when the drum is rotating. In the initial stage, latching pin 32 is engaged with notch 33, when the drum 2 has been revolved so that the pliant sheet 19 is wrapped round the drum, pin 32 engages with notch 34. Latching lever 35 is pivoted at b and is spring loaded in the direction of pin 32. It may be disengaged by operating lever 36 attached thereto. The complete operation will now be described with reference to the drawings.
In operation with the drum in position, with pin 32 in latch 33, the frame 4 is raised to its upper position and the flap 15 is pulled over, a pliant sheet 19 is placed in position on platen 14 and the flap 15 is lowered again. The top edge of the pliant sheet will be resting across the drum surface. Adjustable stops each side and at the bottom of the platform locate the sheet so that its top edge is correctly positioned relative to the drum.
A strip of adhesive tape 37 (FIGURE 1) is stretched between the tape support arms 30, 30a at one end of the drum and its counterpart at the other end of the drum.
The positions of the respective parts are indicated in FIGURES 4a, 4b and 4c.
The handle 21 is then pulled down.
Arm 23 is thus caused to force roller 24 around the cylindrical surface of the drum guided by guides 25.
At the same time pin 28 on crank 27 is forced along the first part of the three-part slot 29 in the cam plate 26 thus forcing crank 27 to rotate counter clockwise to lower the tape support arms 30, 3ia to a position in which half of the tape width overlies the upper edge of sheet 19 and the other half overlies the cylindrical drum surface directly.
At this stage the position of the respective parts are as shown in FIGURES 5a, 5b and 50.
Further movement downwards of the handle 22 causes the roller 24 to roll over the adhesive tape to secure into contact with the drum and with the top edge of the pliant sheet. During this action the tape support arms St), 300 do not change in position since pin 32 is passing along the middle section of the slot 29 which is substantially an arc in relation to the pivot b.
The final part of the movement downwards of handle 21 continues to roll the pliant sheet onto the drum while the third section of the slot 29 moves the crank 27 a further distance counter clockwise disengaging the tape support arms 39, 30a from the tape.
The position then reached is indicated in the FIG- URES 6a, 6b and 6c.
The handle which has been moved down in one continuous movement is then released and restores to the position shown in FIGURE 1.
Having attached one end of the pliant sheet 19 as described the drum 2 is unlatched by depressing lever 36 and the drum 2 is rotated clockwise by hand until pin 32' latches in notch 34 of latching lever 35. During this motion the pliant sheet 19 is progressively wrapped round the drum 2 and pressed into intimate contact therewith by roller 24.
A further strip of adhesive tape is then stretched across between the tape supports 30, 30a and the handle 21 is again operated downwards. By a series of movements identical with those previously described, the tape is applied with half its width overlying the trailing edge of the pliant sheet 19 and half its width overlying the 4. length of tape which is securing the leading edge of the pliant sheet (the trailing edge of the pliant sheet will overlie the half of the first length of tape which is secured directly to the drum) and is rolled out so that it adheres securely.
Latch 12 is then released and the frame 4 lowered to the broken line position so that the drum with sheet 19 wrapped securely around it is available for the transmitting or recording process or for unloading or lifting the drum away.
I claim:
1. A mechanism for attaching an edge of a thin pliant sheet longitudinally across the curved peripheral surf-ace of acylindrical drum, comprising means for mounting the drum for rotational movement, means mounted thereon for supporting a strip of adhesive tape longitudinally across and adjacent to the drum surface, cam means engaging said supporting means for lowering the tape towards the drum surface to overlie the edge of the sheet and the drum surface, roller means secured to said cam means for rolling the strip onto the edge of the sheet and drum surface and means pivotally secured to said supporting means for moving said cam means and roller means to effect said tape lowering and rolling operations.
2. A mechanism as claimed in claim 1, in which said cams means comprises means for releasing the supporting means from the strip of the tape.
3. A mechanism as claimed. in claim 1, comprising spring-loaded means pivotally mounted in relation to the supporting means for latching the drum in an indexed position for the attaching operation.
4. A mechanism as claimed in claim 1, comprising spring-loaded means pivotally mounted in relation to the supporting means for latching the drum in two indexed positions rotationally spaced from each other for separate attaching operation for the respective ends of the pliant sheet.
5. A mechanism as claimed in claim 1, in which the means for mounting the supporting means on the drum mounting means comprise rctractablc means pivotally secured to said supporting means for supporting and locating the sheet, linkage means connecting said retractable team to said drum mounting means and permitting the rectractable means to move between a position presenting the edge of the sheet to the peripheral surface of the drum, and a position in which the retractable means is stored below the drum and releasable latching means attached to the mounting means for securing the retractable means in the former position.
References Cited by the Examiner UNITED STATES PATENTS 301,843 7/84 Wiley. 156-446 701,229 5/02 Strasburger Q 156-446 2,199,033 4/40 Strauss 156-446 3,017,313 1/62 Lagasse et al. 156-446 ROBERT E. REEVES, Acting Primary Examiner. RAPHAEL M. LUPO, Examiner.

Claims (1)

1. A MECHANISM FOR ATTACHING AN EDGE OF A THIN PLIANT SHEET LONGITUDINALLY ACROSS THE CURVED PERPHERAL SURFACE OF A CYLINDRICAL DRUM, COMPRISING MEANS FOR MOUNTING THE DRUM FOR ROTATIONAL MOVEMENT, MEANS MOUNTED THEREON FOR SUPPORTING A STRIP OF ADHESIVE TAPE LONGITUDINALLY ACROSS AND ADJACENT TO THE DRUM SURFACE, CAM MEANS ENGAGING SAID SUPPORTING MEANS FOR LOWERING THE TAPE TOWARDS THE DRUM SURFACE TO OVERLIE THE EDGE OF THE SHEET AND THE DRUM SURFACE, ROLLER MEANS SECURED TO SAID CAM MEANS FOR ROLLING THE STRIP ONTO THE EDGE OF THE SHEET AND DRUM SURFACE AND MEANS PIVOTALLY SECURED TO SAID SUPPORTING MEANS FOR MOVING SAID CAM MEANS AND ROLLER MEANS TO EFFECT SAID TAPE LOWERING AND ROLLING OPERATIONS.
US306532A 1963-07-31 1963-09-04 Drum loading Expired - Lifetime US3166460A (en)

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
GB3033/63A GB1011158A (en) 1963-07-31 1963-07-31 Improvements in or relating to drum loading

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US3166460A true US3166460A (en) 1965-01-19

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Citations (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US301843A (en) * 1884-07-08 -wiley
US701229A (en) * 1901-01-31 1902-05-27 Frank C H Strasburger Labeling-machine.
US2199033A (en) * 1939-02-14 1940-04-30 Ober G Strauss Machine for applying sealing tape to wrapped articles
US3017313A (en) * 1958-06-30 1962-01-16 Northern Electric Co Device for wrapping insulating tape around electromagnet cores

Family Cites Families (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US2145072A (en) * 1936-12-23 1939-01-24 Wide World Photos Inc Telephoto apparatus

Patent Citations (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US301843A (en) * 1884-07-08 -wiley
US701229A (en) * 1901-01-31 1902-05-27 Frank C H Strasburger Labeling-machine.
US2199033A (en) * 1939-02-14 1940-04-30 Ober G Strauss Machine for applying sealing tape to wrapped articles
US3017313A (en) * 1958-06-30 1962-01-16 Northern Electric Co Device for wrapping insulating tape around electromagnet cores

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DE1228296B (en) 1966-11-10
GB1011158A (en) 1965-11-24

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