Transfer device

The transfer device is a circular conveyor having a plurality of radially moveable grippers. The grippers receive a non-self-supporting package, such as a newspaper jacket, on its bottom edge from an overhead line conveyor and rotate the newspaper down onto a receiving device such as a bundler at the bottom of the drum's rotation. The transfer device controls the gripping of the newspaper from the line conveyor with an inhibitor cam to provide a controlled bypass mechanism. The radial moveable grippers allow for smoother transistion and decrease space needs.

BACKGROUND OF THE INVENTION

1. Field of the Invention

The present Invention relates to a device for transferring flat, flexible, non-self-supporting printed products from a line conveyor to a receiving device like a conveyor or a bundler. The present Invention is especially useful for handling newspapers.

2. Art Relating to the Invention

In the graphic arts industry, flat, flexible, non-self-supporting printed products, such as newspapers and magazines, are moved by line conveyors. At some point along their path, the product has to be transferred from the line conveyor to another conveyor, a bundler, or other type of receiving device for further processing a stacker. The bundler/stacker prepares stacks of product for shipment, future binding, handling, or processing.

Typically, a line conveyor, as employed in the graphic arts industry, is a horizontally oriented endless chain which is equipped with a plurality of vertically oriented grippers. The grippers clamp the top edge of the product and transports the product to the receiving device. When the product arrives at the receiving device, the gripper opens its jaws to allow the product to fall from the gripper onto another conveyor, a platform or stack of other products, depending on the type of receiving device to which the product is transferred to at the transfer point.

One of the transfer devices used with bundlers/stackers as taught in U.S. Pat. No. 5,218,813 uses a circular conveyor which transfers the product from the line conveyor to the bundler/stacker. The circular conveyor employs grippers which grip the bottom edge of the product and rotate the product around to the bundler/stacker.

There is a point in time, just prior to release of the product from the line conveyor gripper, when the product is held by both the line conveyor gripper and the circular conveyor gripper. At this point in time, the product is subject to forces in opposite directions which can lead to problems in transferring the product from one conveyor to the other.

Additionally, there are times when the product is intended for a subsequent bundler/stacker and the line conveyor gripper does not release the product. In this situation, the circular conveyor grippers pulls the product out of the jaws of the line conveyor grippers. There is a need to avoid the fight between the line conveyor grippers and the circular conveyor grippers.

SUMMARY OF THE INVENTION

It has now been discovered that, by employing a circular conveyor with each circular conveyor gripper having both radial and circular motion, that a smooth transition of the product occurs between the line conveyor gripper and the circular conveyor gripper. The grippers of the circular conveyor gripper receive the product directly from the jaws of the line conveyor gripper and move the product to deposit it directly to a receiving device. Radial movement is suitably provided by mounting each circular conveyor gripper on a slide which moves the gripper in a radial direction with respect to the rotation of the circular conveyor.

The circular conveyor grippers of the present Invention are conventional grippers wherein the jaws are spring biased in a closed position and cams are used to open the jaws. Opening cams, positioned at the top and bottom of the rotational path of the circular conveyor, are employed for opening the circular conveyor grippers using a conventional cam follower which is mounted on one of the jaws of the circular conveyor gripper. The top opening cams are employed for opening the circular conveyor gripper to receive the product and the bottom opening cam for opening the circular conveyor gripper to deposit the product onto the receiving device.

It has also been discovered that an inhibiting cam device, which controls the closing of the circular conveyor gripperas it receives the product, provides better control for receiving the product and avoids a tug of war between the line conveyor gripper and the circular conveyor gripper when the product is intended to be carried by the line conveyor to a subsequent receiving device more particularly, the inhibiting cam device is a rotatable assembly of a plurality of inhibiting cams which act on the circular conveyor gripper as it closes about the product and starts its downward movement to the stacker/bundler.

Additionally, it has been found that, if the bottom opening cam is adjustable as to the release point of the product, the bottom opening cam allows for a constant point of release of the product regardless of the thickness of the product.

Preferably, a copy stripper is mounted opposite the bundler/stacker so as to remove the product from the jaws of the circular conveyor gripper.

It is also preferred that one or more pans be employed adjacent to the circular conveyor but, downstream of the circular conveyor, so that, as the product is received from the line conveyor gripper, it is controlled during its movement downward to the receiving device

Preferably, the receiving device employed with the transfer device of the present Invention is a bundler/stacker.

When the receiving device is a bundler/stacker, it is preferred that the stacking fork of the bundler/stacker have a homing sensor to permit automatic setting of the stacking fork relative to the circular conveyor.

These and other aspects of the present Invention will be more readily understood by reference to one or more of the following drawings.

DETAILED DESCRIPTION OF THE INVENTION

In the detailed description of the Invention, reference will be made to newspaper jackets or, more simply, jackets as the flat, flexible, non-self-supporting printed product. Additionally, reference will be made to a bundler/stacker as the receiving device. It will be understood that other receiving devices can be employed with the present Invention and that other products besides newspapers can be handled by the present Invention.

FIG. 1illustrates a preferred embodiment of the transfer device of the present Invention employed as a bundler infeed device wherein a circular conveyor shown as gripper drum20has a plurality of circular conveyor grippers or drum grippers22positioned around its periphery. Drum grippers22have been numbered1through12to distinguish each from the other. Gripper drum20rotates about center of24in the direction of arrow A. Drum grippers22follow drum gripper tip path26. Drum grippers22are mounted on slide28which provides the radial movement of drum grippers22.

Drum grippers22are of a conventional construction having jaws which are spring biased in a closed position as shown by drum gripper No. 11, for example.

Gripper drum20is positioned below line conveyor30. Line conveyor30has a plurality of line conveyor grippers34which hold jacket32of a newspaper. Conveyor30moves in the direction of arrow B.

Below gripper drum20is positioned articulating stacking fork36and its articulating mechanism38. Drum grippers22receive jacket32and deposits jacket32onto fork36, all this being accomplished by the rotation of gripper drum20in the direction of arrow A.

In order to open drum grippers22as they move to the top of the rotation of gripper drum20, top opening cam40is fixed in position on the outside of gripper drum20. As shown inFIG. 1, top opening cam40acts on gripper Nos.1,2,3, and4as they rotate towards the top of their path of rotation. Top opening cam40operates on drum grippers22in a conventional manner by means of cam follower66which is part of each of drum grippers22.

In order to control the closing and removal of jacket32from line conveyor gripper34, inhibiting cam assembly41is used to control the closing of drum grippers22about jacket32. Inhibiting cam assembly41employs a plurality of inhibiting cams42which rotate about center43. As shown inFIG. 1, inhibiting cams42have been numbered to correspond with drum grippers22upon which they act. In other words, as shown inFIG. 1, inhibiting cam No.6,12operates on drum gripper No.12and drum gripper No.6. Likewise, inhibiting cam No.5,11operates on drum gripper No.11and drum gripper No.5. As will be appreciated, the number of inhibiting cams42is half the number of drum grippers22. As also will be appreciated, inhibiting cam assembly41rotates twice around for each rotation of gripper drum20.

As jacket32is carried to the bottom of the rotational cycle of gripper drum20, bottom opening cam44operates on cam follower66to open drum gripper22and allow jacket32to be deposited on articulating stacking fork36or the stack of jackets32which are on stacking fork36. Bottom opening cam44is adjustable to accommodate different thickness of newspaper and functions in a conventional manner by forcing one of the jaws away from the other.

In order to assist in the depositing jacket32under fork36, copy stripper46is employed. Copy stripper46is a conventional piece of equipment which is employed in a conventional manner in order to assist in a speedy removal of jacket32onto fork36. InFIG. 1, only one cam follower51is illustrated for drum gripper No.9in a breakaway portion of FIG.1. The non-circular movement of the drum grippers22is provided by cam surface50aon cam follower51. The radial motion of drum gripper22is illustrated by drum gripper tip path26. As can be seen, this path is somewhat flat at the top of rotation of drum20, such that the line of travel of drum gripper22is approximately parallel to the line of travel of line conveyor gripper34. This aids in avoiding a tug-of-war and aids in a smooth transition of jacket32from line conveyor gripper34to drum gripper22.

The radial motion of drum gripper22is also evident in the downward path of drum gripper22wherein the downward path of drum gripper22is approximately vertically downward as shown in FIG.1.

Furthermore, the radial movement of drum gripper22is seen at the area of contact between drum gripper22and stacking fork36. By having the line of travel of drum gripper22approximately parallel to the flat surface of fork36, a smooth transition between the circular conveyor and the bundler is obtained.

Additionally, by employing radial movement for drum gripper22, a space savings is obtained. Obviously, an approximate parallel line of travel between line conveyor30and drum gripper22, and fork36and drum gripper22, can be obtained if the diameter of drum20is very large. Radial movement of drum gripper22allows for a smaller diameter drum while still obtaining relatively parallel movement.

Radial cam50is employed to act on a cam follower51mounted on each slide28to provide radial movement of drum gripper22.

In order to control the movement of jacket32during its downward decent from line conveyor30to fork36, upper pan52and lower pan54are employed. As will be appreciated, drum grippers22grabs the bottom edge of jacket32while pans52and54help maintain the top edge of jacket32in an upward direction during its downward movement. This assists in preventing inserts, which are in jacket32, from escaping. The distance, which pans52and54are spaced from tip path26, depends primarily on the size or dimension of jacket32.

As will be appreciated,FIG. 1does not illustrate the framework which is associated with the various elements. Such framework is conventional and is employed to maintain the relative position of the various elements.

Also, as will be understood, fork36and its associated articulated mechanism38is movable so as to move the stack of jackets32away from gripper drum20as the stack grows and to allow an empty fork36to be positioned in place. The stack, which is formed on fork36, can either be stored for future use or banded in a conventional manner for shipment. Both stacking fork36and its associated mechanism38, as well as a banding mechanism, are conventional.

Turning toFIG. 2, details of the inhibitor cam assembly41are illustrated in a perspective view. As shown inFIG. 2, there are six inhibitor cams42which are part of assembly41. Enabling cam60, which is shown in the retracted position inFIG. 2, is retracted by fluid activation from valve62as shown in FIG.5. In the retracted position, enabler cam60is retracted. Enabling cam60is spring loaded to be in an extended state as shown inFIG. 3without activation from air via fluid valve62. When enabling cam60is retracted, inhibiting cams42are in position to allow closing of drum gripper22by acting on cam follower66. Thus, opening and closing of drum grippers22is controlled via valve62.

Turning toFIG. 3,FIG. 3illustrates enabling cam60in an extended position which, in turn, shows inhibitor cam42extended into the path of gripper cam follower66. With gripper cam follower66acted upon by inhibitor cam42, drum gripper22is maintained in a slightly open position as shown by drum gripper No.12in FIG.1.

Reset cam64operates on all inhibitor cam42to move them to the extended or inhibiting position as shown in FIG.3. This is the natural or rest position of inhibitor cam42. When inhibitor cam42is retracted, it moves to right inFIG. 3, gripper cam follower66is no longer acted upon by inhibitor cam42and drum gripper22can close on jacket32, as shown in FIG.5.

FIG. 4illustrates drum gripper22and inhibitor cam assembly41, as shown inFIG. 3, wherein inhibitor cam42is operating on cam follower66to maintain drum gripper22in a slightly open position.

As shown inFIG. 4, drum gripper22follows the rotation as indicated by arrow A while inhibitor cam42rotates about center43and moves in the direction of arrow C. As will be appreciated, inhibitor cam assembly41is operated by belt68which is operated upon the axle that drives gripper drum20. As will be appreciated by one of skill in the art, inhibitor cam assembly41can be independently driven, however, it is suitable that a standard servo drive be employed so as to coordinate, not only the movement of gripper drum20with respect to conveyor30, but also to coordinate the movement of inhibitor assembly41and gripper drum20.

Turning toFIG. 5, enable cam60is shown in the retracted state which, in turn, allows inhibitor cam42to be in the retracted state and out of the path of cam follower66. In such an arrangement, drum gripper22closes so as to hold jacket32tightly between its jaws. Referring back toFIG. 1, this is the position of gripper No.10which is shown leaving the area of operation of inhibiting cam assembly41on its downward movement towards fork36.

By controlling the opening and closing of drum grippers22with inhibitor cam assembly41, selected jackets32can bypass one device of the present Invention and pass to a subsequent transfer device.

While only a limited number of specific embodiments of the present Invention have been expressly disclosed, it is, nonetheless, to be broadly construed and not to be limited except by the claims appended hereto.