APPARATUS FOR REMOVING ARTICLES ADHERENT TO A WEB

Abstract: Apparatus for stripping thin flexible articles releasable adherent to a backing web employs a vacuum chuck which is brought into contact with an article on the web and travels in contact with the article as the web moves along a rectilinear path. At the end of the path, the web is curved round the sharp edge of a stripping plate in a direction away from the chuck, and this curve, together with the suction of the vacuum chuck, strips the article from the web, leaving it adherent to the chuck.

Description: This invention relates to an apparatus for removing thin flexible articles from a web. One application of the present invention is in the application of dampening rings to print wheels of the type generally known as daisywheels. Such a print wheel comprises a central hub portion with flexible radial arms, each carrying a print head at its outer end, extending from the hub. A dampening ring for such a print wheel comprises a thin ring of flexible material of diameter slightly greater than that of the hub. The ring is fixed to all of the radial arms at a position just outside the hub so that is surrounds the hub. It's purpose is, of course, to dampen oscillatory motion of the arms during print operations. Dampening rings are currently applied to typewriter printwheels by hand. This is a tedious and time consuming task with a large margin for error since each ring which is made of thin flexible material, must be applied to the typewriter printwheel so that its radius is maintained constant and there are no bubbles or creases. The dampening rings come in large rolls and are adherent to one side of a backing or web. The rings must be removed from the backing and pressed into the position on the the printwheel where they are to be utilized. U. S. patent 3,271,227 issued September 6, 1966 teaches the removal of gummed labels from a backing strip by moving the backing strip carrying the labels around the edge of a stripping plate which causes the label to separate from the backing strip and fall to a position below, where a document onto which the label is to be pressed is located. The label must be sufficiently stiff to separate from the backing strip as it moves over the stripping edge. USP 4,303,461 describes apparatus for removing thin articles releasably adherent to a surface of a web having first and second parallel strip portions. The apparatus comprises a web transport for passing the web along a rectilinear path terminating in a V shaped edge. The web transport pulls the web towards the apex of the v-shaped edge. As the web is drawn over the V shaped edge, the strip portion are pulled in diverging directions to sequentially release the articles. USP 4,479,839 also describes apparatus for removing thin flexible articles releasably adherent to a surface of a web. The apparatus comprises a linearly reciprocating web transport for passing the web along a rectilinear path terminating in an edge for bending the web through an angle with the surface outward. A head also moves in a reciprocating manner and uses air suction to remove articles from the web as the articles are stripped from the web by the edge. The articles are then blown out of the head by a positive air stream. It is the main object of the present invention to provide apparatus for removing thin flexible articles from a backing web to which they adhere. According to the invention, there is provided apparatus for removing thin flexible articles releaseably adherent to a surface of a backing web, comprising: a web transport for passing the web along a rectilinear path; web bending means for bending the web at the end of said path through an angle with said surface outward; a chuck for engaging and holding said articles individually; a chuck drive for driving said chuck parallel to and in the same direction as the web when in the rectilinear path, while engaging and holding a said article adherent to the web, said drive having a first transport supporting the chuck for movement, at the same velocity as the web, past said end of the path whereby as the web bends, the article engaged and held by the chuck is disengaged from the web and retained by the chuck, and a second transport supporting the chuck for movement relative to the first transport to transport the article to a predetermined work position subsequent to disengagement from the web. An embodiment of the invention will now be described, by way of example, with reference to the accompanying drawings, in which: Fig. 1 is a schematic elevational view of the apparatus for removing thin flexible gummed rings from a backing and placing them in position for use; Fig. 2 is a schematic representation of a section of backing showing the gummed rings adhered thereto; Fig. 3 is a schematic elevational view on an enlarged scale showing the vacuum head and its transport mounted in the apparatus; Fig. 4 is a sectional view along the line 4-4 of Fig. 3 showing more details of the vacuum head; Fig. 5 is a sectional view along the line 5-5 of Fig. 1, showing the intermittent index drive for the web; and Fig. 6 is an illustrative view of the drum operations of the intermittent index drive of Fig. 5. The present apparatus is operable to strip dampening rings from a backing web for placement on to print wheels. Fig. 2 shows the arrangement of the rings on the backing web. The rings 10, which are about 0.2 mm thick, and have inside and outside diameters of 46.2 mm and 63.5 mm respectively, are spaced at 65 mm centres on the backing web 14 which is formed, for example, from paper. The web is about 101 mm wide. the hole at the centre of each ring corresponds exactly with a corresponding hole in the backing web. A reel of the web, as shown at 18, Fig. 1, of 457 mm diameter, carries about 9000 of the rings. A web roll 18 is shown in Fig. 1 with the backing web threaded through the apparatus. The webbing 14 is first strung through the compensating tension web controller 22 and then enters its horizontal run 24 through the apparatus. At the end of the horizontal run 24, the web is placed around the sharp edge 26 of the stripping tool plate 28 and is fed through the index drive mechanism 30. A hand operated pilot or plug 38 is raised from the tooling plate recess and the opening or inside diameter of a ring 10 along the straight run of the web is positioned thereover. This establishes a starting position of the web 14 carrying the rings 10 in the machine. The web 14 is then pulled tight around the sharp edge of the stripping plate 26 and wound around the knurled web drive roll of the intermittent index drive 30 while clamped to the drive roll by roller clamps 42. Referring now to Figs 3 and 4 in conjunction with Fig 1, a vacuum chuck 34 is located above the horizontal run 24 of the webbing 14 and is so located as to be above and indexed with a ring 10 preceding the ring which has its inner diameter located by the pilot 38. The vacuum chuck 34 is driven vertically up and down a fixed amount by an air cylinder 40. The bottom of the chuck 34 contains a vacuum head 35 which has its bottom surface formed of a porous stainless steel ring 37, shown in Fig. 4. In operation the vacuum chuck 34 is lowered by cylinder 40a and contacts the ring 10 located therebelow. The vacuum is energized which holds the ring 10 against the stainless steel ring 37 of the vacuum head 35. An air jet manifold 44 is energized which applies an air stream against the bottom of the webbing 14 at the ring 10 aiding the holding of the ring against the stainless steel ring 37 of the vacuum chuck 34. The air jet remains on until the vacuum chuck 34 completes its travel. The vacuum chuck 34 is moved horizontally along the horizontal path of the web 14. The vacuum chuck 34 is mounted within a transporter 48 which is mounted in the apparatus or fixed frame for movement along rail 49. The transport 48 is arranged to move horizontally 65 mm, which is the distance between centres of adjacent rings 20 on the web 14. The transport 48 is driven by a motor 50 and drive ball screw assembly 52. The transport 48 has a gear rack 54 attached thereto which moves with it. The gear rack motion causes rotation of an idler gear 56 which in turn causes rotation of the knurled web drive roll 40 which pulls the web 14 through the machine the given 65 mm, thereby synchronizing the movement of the vacuum chuck 34 with the web 14. As the vacuum chuck 34 moves, the ring 10 held against the vacuum head ring 37 moves, since it is still stuck to the web. As the web 14 moves around the sharp edge stripping tool plate 26, the chuck 35 holding the ring 10 continues to move horizontally thus stripping the ring 10 from the webbing 14. A photocell 32, located along the diameter of the ring in the direction of motion, is of the reflective type and is set to detect the inner diameter of the ring 10. It should be noted that this detection of the inner diameter is made in a subsequent ring 15 following the ring 10 that is peeled or removed from the web 14. This, detection is utilized to stop the movement of transport 48. The cylinder 40 is now energized to lift the vacuum chuck 34 to its raised position. The vacuum chuck 34 is carried by a transport 55 which is mounted on rails 45 for movement within transport 48. This movement is obtained by an air cylinder 58 which causes movement of the transport 55 by 292 mm, when the cylinder 40 is again operated to move the vacuum holding chuck 34 down on to a printwheel, thereby placing the ring 10, sticky side down, against the printwheel. The vacuum chuck 34 is then raised and the transport 55 carrying the vacuum chuck 34 is returned by means of cylinder 58 to its starting position. Transporter 48 is moved in reverse via the ball screw assembly 52 and motor 50 which has a reversible clutch, brake 53 located between the motor 50 and the ball screw drive assembly 52. The reversible clutch brake 53, in the reverse setting, is operable to drive the ball screw assembly 52 to move the transport 48 in the reverse or return direction. Fig. 5 is a cross sectional view along the line 5-5 of Fig. 1 showing the knurled web drive roll 40, the right hand clutch drive 66 and the left hand clutch drive 70. As was previously mentioned, the web 14 is fixed for rotation on the knurled drive drum 40 by clamp rolls 42. Fig. 6 shows schematically the gear rack 54 and the intermittent index drive 30, which includes the idler gear 56 and the drum drive gear 40, in two settings. The first, which is shown in the left hand half of Fig. 6, shows the gear rack 54 in the finished drive position. This would be the setting wherein the gear rack 54 covered by the transport 48 is at its extreme left hand or extended position having stripped a ring 10 from the backing 14. In getting to this position, the clutch 66 is in the slip condition allowing the shaft 68 of the drum 62 to turn freely therein. Clutch 70 is locked to the shaft 68, thereby allowing drum 40 to rotate when the drive gear 40 is driven by idler gear 56 which is in turn driven by the gear rack 54. It should be appreciated that this arrangement of the gear rack 54, idler gear 56, and drum drive gear 40 moves the webbing 14 in synchronism with the transport 48 which in turn carries the vacuum holding chuck 34 to effect the stripping of a ring 10 from the webbing 14. A ring 10 is stripped from the webbing per each cycle of the apparatus. When the transport 48 is returned to the start position, as shown in the right hand illustration of Fig. 6, the clutch 66 is energized or locked, holding shaft 68 from turning. At the same time, clutch 70 slips, thereby providing no movement of the drum 72 when idler gear 56 is driven in the counter clockwise direction as indicated by the arrow thereon as a result of the gear rack 54 returning to the start position.

Claims: Apparatus for removing thin flexible articles releaseably adherent to a surface of a backing web (14), comprising: a web transport (22,30) for passing the web along a rectilinear path (24); web bending means (28) for bending the web at the end of said path through an angle with said surface outward; a chuck (34) for engaging and holding said articles individually; a chuck drive (45,48,55,58) for driving said chuck parallel to and in the same direction as the web when in the rectilinear path, while engaging and holding a said article adherent to the web, said drive having a first transport (48) supporting the chuck for movement, at the same velocity as the web, past said end of the path whereby as the web bends, the article engaged and held by the chuck is disengaged from the web and retained by the chuck, and a second transport (55) supporting the chuck for movement relative to the first transport to transport the article to a predetermined work position subsequent to disengagement from the web. Apparatus according to claim 1, in which the web bending means comprises a stripping plate (28) positioned adjacent said rectilinear path, said plate having an edge (26) positioned at the end of the path round which said web is directed to pass through said angle. Apparatus according to claim 2 in which said edge is a sharp edge at which the entering and exiting portions of the web form an actue angle with respect to each other. Apparatus according to any one of the previous claims, in which said chuck comprises a vacuum head. Apparatus according to claim 5, including an air jet nozzle (44) positioned adjacent said end of the path for assisting the disengagement by directing an air jet to said end of the path. Apparatus according to any of the previous claims, in which the chuck drive includes a return drive (40) for driving the chuck at right angles to the direction of the web along the path, whereby the chuck is returned to a position away from the path and drive toward the web to engage a said article. Apparatus according to any one of the previous claims, in which said articles are equally spaced along the web and the chuck is positioned to locate a said article on the web by a detector (32) for detecting the location of an article immediately succeeding the said article on the web. Apparatus according to claim 7, in which said articles are ring shaped and said detector detects the area within the succeeding ring. Apparatus according to claim 8, in which the web has apertures corresponding to areas (36) within the rings on the web, and said chuck is positioned by locating an interconnected pilot (38) within the aperture of said immediately preceding article. Apparatus according to any one of the previous claims, in which said web transport includes an index drive (30) to index the web by lengths equal to the spacing of the articles on the web. Apparatus according to claim 10, in which said index drive comprises a rack and pinion assembly (54,56) coupled between chuck drive and a web drive roller (72).

Inventors: ASHCRAFT, GLINDEN RAY, GORMAN, RICHARD EARL, KOZOL, EDWARD JOHN, PAUL, ROBERT JOSEPH
Applicants: INTERNATIONAL BUSINESS MACHINES CORPORATION
Application year: 1988
Main classification: B65H5
IPC codes: B65H3, B41J1, B65C9, B65H41, B65H37