GB2088339A

GB2088339A - Separating and removing groups of sheets and signatures from a stack

Info

Publication number: GB2088339A
Application number: GB8130053A
Authority: GB
Original assignee: Stobb Inc
Current assignee: Stobb Inc
Priority date: 1980-11-10
Filing date: 1981-10-05
Publication date: 1982-06-09
Also published as: IT1142846B; DE3140064A1; SE8105842L; JPS57107355A; NL8104517A; SE451066B; IT8149420A0; FR2493817A1

Abstract

A rotating separator (46) separates a group of sheets or signatures from a stack to an intermittently rotating set of grippers (14) which then removes the separated signatures and place them on conveyor (11). The signatures are then conveyed to gatherer (13) for a binder. A sensor (42) activates the intermittent movement of the separator (46) and the grippers (14) when it senses a low level of signatures in the gatherer (13). The separator (46) can be a brush- or irregular-surfaced roller. <IMAGE>

Description

SPECIFICATION System for supplying sheets to a gatherer This invention relates to a system for supplying sheets to a gatherer, and, more particularly, it relates to a system for handling sheets in the graphic arts industry in the assembly of a magazine or book, such as in the bindery.

Background of the Invention The prior art is already aware of various means and methods for processing a stack of sheets or signatures to move the signatures to a bindery feeder hopper and gatherer. In that prior arrangement, the signatures are moved in single form from the stack to the gatherer, and that is either by discretely and separately moving each signature or by moving the signatures from the stack in a stream formation. U.S. Patents 3,416,679 and 3,739,924 show feeder mechanism and methods for moving the signatures in separated and single form from a stack of signatures and to a gatherer. In those examples, a sheet gripper is supported on an arm which moves to the front of the stack to separately remove the sheets therefrom. Other prior art examples of grippers for engaging and moving single sheets are found in U.S.Patents 1,406,978 and 2,699,333 and 2,797,097 and 3,096,088 and 3,510,119. Hsre the U.S. Patent 3,510,119 is typical of this group of patents in that it shows a gripper moving the sheets singly from a stack of sheets or signatures. Still further, U.S. Patent 3,982,749 shows a signature feeder where a stream of signatures is constantly fed to a signature gatherer and off a stack of signatures.

Finally, the prior art is also aware of utilization of brushes for loosening and separating sheets in a stack of sheets so that the sheets can be handled or singly removed from the stack or removed in a stream, and U.S. Patent 3,501,139 shows a brush for that purpose.

The present invention improves upon the prior art in that it recognizes the problem of either moving the sheets singly from a stack or moving them in a stream relation from the stack. In both instances, there are problems in engaging the sheets and moving them at a controlled and uniform rate into the gatherer, according to the requirements and demands of the gatherer. That is, in the prior art apparatus and methods for taking the signatures either singly or in stream form from the stack, there are numerous conditions which vary with changes in the paper in the signature, the type of fold in the signature, and even the amount of ink coverage on the signatures, and such conditions and characteristics create problems and interfere with efficient and neat transfer from the stack to the gatherer.

Accordingly, the present invention improves upon the prior art and it generally accomplishes the transfer of the signatures from the original stack and in a smaller stack or group, rather than singly or in stream or shingle form, to the gatherer.

As such, the signatures can be transferred accurately according to the demand therefor and they can be accurately and neatly laid in the gatherer. With this arrangement, the equipment operates only when an additional small group of signatures is required by the gatherer, and the equipment need not be operating continuously or frequently intermittently in order to supply single sheets or a stream of sheets to the gatherer.

In one embodiment, the present invention utilizes a rotating member, such as a rotary brush, which engages the main stack and separates a plurality of the signatures from the main stack and thus presents that plurality or smaller group of signatures to a gripper which can transfer those signatures to the feeder mechanism. Further, in transferring the signatures in forms of small stacks, as mentioned, the rotary member or brush, or like separator, actually works and flexes the signatures so that they are more easily handled by the feeder mechanism and they will not be either out of line or stuck together when they are in the feeder mechanism.

Advantageously, the illustrated embodiment of this invention provides a noval apparatus and method for supplying signatures to a gatherer by means of synchronizing, through interrelated controls, the movement of the original stack of signatures and the separating of the group or small stack of signatures and the movement of the gripper mechanism which deposits the small stack on the gatherer or the like.

The invention will now be described further with reference to the accompanying single figure of drawings which shows a side elevational view of a preferred embodiment of this invention.

Detailed Description of the Preferred Embodiment and Method The drawing shows a preferred embodiment, and the method invention is also disclosed in conjunction with the description of the preferred embodiment and the specification thereof. A stack of sheets or signatures S is shown supported on a suitable support, such as a conveyor 10 which moves in the direction of the arrow shown thereon. The stack is therefore supported for movement to the right, as viewed in Figure 1, and the support may be either a movable or stationary support but the stack S will move to the right, as mentioned.The basic idea is to separate a group of the sheets from the stack and form a smaller group or bunch G and lead that plurality of sheets onto a receiver or conveyor 11 which in turns passes the sheets to a feeder mechanism 12 which is adjacent a gatherer hopper 1 3. Thus, the group G is ultimately placed in the hopper 13 along with the other sheets or signatures s shown in the hopper 13 which is a part of a standard gatherer.

A gripper mechanism 14 is operable adjacent the leading end of the stack S to pick up the group G and to transport it as mentioned. That is, the stack S moves in a line of direction to the right, as viewed in Fig. 1 , and that is in the direction of the gripper 14 which is shown to be L-shaped to have the two angled portions shown. The gripper 14 is pivotably mounted on a pin 1 6 affixed to a gripper wheel or rotatable member 17 having an exterior surface 18 which is shown to be circular and which can be presented to the stack S, as shown in Fig. 1 so that there can be contact therebetween at the location designated 1 9. There may be four grippers 14 pivotably mounted on the gripper wheel 1 7 at the pivot pins or locations 16, as shown.The gripper wheel 1 7 rotates in the direction of the arrow designated A.

Thus, upon rotation of the member 1 7 and movement of the gripper 14, the gripper portion or finger 21 will engage the sheet group G and hold it against the surface 1 8 to transport it from the stack S and down onto the conveyor or feeder mechanism 11. A pivotably mounted restrainer bar or the like 22 is pivotably disposed on a pin 23 at the leading end of the stack S to hold the stack S at its upper surface 24, and also a stationary bar 26 is interposed between the stack S and'the wheel 1 7 to preclude the stack S from engaging the wheel 17 at the upper end of the stack S. Of course, it will be seen and understood that the sheets or signatures s in the stack S are generally in an upright position, and they present a bottom edge or surface 27 resting on the support 10.

Further, the restrainer bar 22 is shown to have a spring 28 connected thereto so that the bar lower end 29 is urged into contact with the stack S for the purpose mentioned.

Each gripper 14 has a cam follower 31 affixed thereto and carries a follower roller 32 which engages the surface of a stationary cam 33. The cam 33 has its camming exterior 34 as shown, for the purpose of sequentially closing and opening the gripper 14 when the wheel member 17 positioned the gripper 14 at the positions designated nine o'clock and six o'clock, respectively. Also, tension springs 36 are mounted on the wheel 1 7 and connect to the grippers 14, as shown, and thus urge the grippers in the clockwise direction with respect to their mounting pins 1 6 and thus also retain the roller followers 32 in rolling contact with camming surface 34.

A drive mechanism, such as a motor 37, is suitably connected with a drive connector 38 extending to the shaft 39 on which the wheel 17 may be mounted, and this creates the counterclockwise rotation indicated for the wheel 1 7.

Also, the conveyor 11 is interconnected with the driver mechanism 37, and the arrangement is such that the wheel 1 7 and the conveyor 11 are moved in a pulsating manner so that they operate comparable to a quarter degree turn and then stop with respect to the wheel 17, for instance. Thus, one gripper 14 is presented to the stack S while another gripper 14 has stopped and deposits its group G onto the conveyor 11, and the process continues in that manner of intermittent movement and operation. However, the conveyor 12 can be driven by a motor 41 which operates continuously to deposit the sheets or signatures in the gatherer 1 3.

A sensor 42 is adjacent the gatherer 13, and it is shown to have pivot arm 43 which contacts the top of the sheets s in the gatherer 1 3 to detect the quantity of sheets in the gatherer 1 3. When the quantity is low, then the sensor 42 recognizes the low capacity and is actuated in response to that signal. A connector 44, and it may be in the form of an electric wire, is shown connected with the sensor 42 and the drive mechanism 37 for actuating the wheel 1 7 and the conveyor 11 in response to the reading of a low quantity in the gatherer 13, as mentioned.

A separator, in the form of a brush 46, is disposed adjacent the forward moving end of the stack S and extends into the stack surface 27, as shown. As such, the separator 46 serves as a stop for the stack S, and the sheets in the stack cannot move to the right of the separator 46 unless and until the separator 46 is rotated in the clockwise direction. To create that rotation, a motor 47 is connected with the separator 46 which can therefore rotate to the right and brush the sheets in the stack and to position them to the right of the separator 46, as shown by the group G in Fig. 1.

Also, a combined brake and clutch mechanism 48, of a conventional construction, is connected with the motor 47 and is also connected with the sensor 42 by means of the wire 49, as shown.

Thus, the sensor 42 energizes the motor 47, through the clutch and brake 48, to rotate the separator or brush 46 and thus create the separated plurality of sheets or the group G.

In operation, the wheel 1 7 rotates to position one of the grippers 1 4 adjacent the leading end of the stack S. Then, the brush or separator 46 is rotated to form the group of sheets G.

Subsequently, further rotation of the wheel 1 7 will cause the gripper 14 to engage the group G, as shown in Fig. 1, and to hold it against the wheel surface 1 8 and then transport it to the lower position shown below the wheel 17 where the group G is being deposited on the feeder mechanism or conveyor 11. Next, the further rotation of the gripper 14 in its lowest position as shown will cause the finger 21 to be released from the group G, by virtue of the cam arrangement shown and described, and thus the gripper 14 will swing counter-clockwise and out of the way of the group G while the wheel 1 7 moves the gripper 14 further outof the way and the conveyor 11 moves the group G onto the conveyor 1 2 and into the gatherer 13. In that operation, the separator 46 can restrain the remainder of the stack S at least until the next gripper 1 4 is positioned generally in the position of the gripper 14 shown on the left in Fig. 1, and then the cycle can be repeated. Also in that arrangement, a roller 51 can be positioned on the bottom of the restrainer arm 22 to hold the sheets but to permit them to move when the wheel 1 7 is rotated to move the group as described.

Thus, the apparatus to the left, as viewed in Fig. 1, of the receiver 1 2 and its drive mechanism 41 is operated pulsatingly, while that to the right, namely, the conveyor or receiver 12, is operated continuously. In that manner, the group G is neatly positioned onto the conveyor 11 which moves in precise synchronization with the movement of the gripper 14 which is then depositing the group G on the conveyor 11 since the gripper 14 and the conveyor 11 stop and start and move in unison.

Further, the mechanisms shown and described are of the constructions shown, and, those that are not shown in detail are conventional and function for the purposes mentioned. Also, the foregoing description provides a specification and description of the method invention presented herein. Thus, the sequence of operation may be such that the rotating member 1 7 is operated while the conveyor 11 is also operated to move the group G then positioned on the conveyor 11.

That 90 rotation positions the gripper 1 4 adjacent the stack S. Then the separator 46 is operated to separate out the group G for that gripper 14. Further rotation of the member 17 causes the gripper 14 to grasp the group G and hold it against the circumference of the member 1 7 and to move the new group G onto the conveyor 11, and the cycle is then repeated. All of the foregoing is stimulated by the sensor 42 which detects the need for additional sheets or signatures in the gatherer 13, and the sensor 42 is of a conventional arrangement and may be a photocell or the like which is suitably operationally connected with the drive mechanisms 37 and 47 and thus the rotating member 17 is also connected into that system of pulsating drive for the squential operations mentioned.The brush 46 may be of a conventional nature such as a metal or like cylinder having irregular exterior circumferential surface, or it may have protrusions, such as bristles, for engaging the sheets or signatures along their surface or edges 27. In the arrangements shown and described, it is understood that the cam action for the grippers 14 is adequate for permitting the grippers 1 4 to clear the members 26 and 51 as well as clearing the stack S to position the gripper 14 underneath the stack S, such as in the position shown for the gripper 14 on the left as viewed in Fig. 1, and of course the same is true for clearance with the brush 46 which may be a discontinuous cylinder extending for the width of the stack S, for the necessary clearance for movement of the gripper 14 to its operative positions.The separator 46 can serve as a stop for the stack S to retain the stack to the left of the separator 46, as viewed in Fig. 1, until the separator 46 is rotated to move that plurality of sheets or signatures to the right of the separator 46 and into its group G, as then shown in Fig. 1. It will of course be understood and apparent that the wheel 1 7 has the necessary spaced-apart portions for receiving and accommodating the four grippers 1 4 so that the wheel circumference 1 8 can flank the grippers 14, for instance. Also, the separator 46 has the necessary opening therealong for the movement of the gripper 14 past the separator 46, as is apparent in this disclosure. The separator 46 is suitably driven by the driving mechanism or motor 47 by means of the interconnecting drive shaft 52, and the separator 46 will rotate in the direction of the arrow shown adjacent the separator 46.

Claims

1. In a system for supplying sheets to a sheet gatherer from a stack of sheets movable in one direction, a sheet gripper mechanism movably disposed adjacent said stack of sheets for picking up the sheets from said stack of sheets and moving them away from the remainder of said stack of sheets, a sheet gatherer, and a movable feeder mechanism in sheet movement communication with said gripper mechanism and said sheet gatherer for receiving the sheets from said gripper mechanism and depositing the sheets on said sheet gatherer, the improvement comprising a powered separator disposed adjacent the leading end of said stack of sheets for separating a plurality of the sheets in said stack of sheets into a group separate from the trailing remainder of said stack of sheets, and said gripper mechanism being movable into contact with said plurality of sheets for gripping said plurality of sheets and moving said plurality of sheets in a group form from said stack of sheets and to said feeder mechanism.

2. The system for supplying sheets to a sheet gatherer as claimed in Claim 1, including drive mechanism operatively and respectively connected with said separator and said sheet gripper mechanism for actuating those two items, and controls operatively and respectively connected with each said drive mechanism and being responsive to the quantity of sheets on said feeder mechanism to thereby control the actuation of each said drive mechanism and move said sheets from said stack to said feeder mechanism.

3. A system for supplying sheets to a sheet gatherer as claimed in Claim 1 or 2, including a control operative on said sheet gatherer, and wherein said control is a sensor having facilities for detecting the quantity of sheets on said sheet gatherer.

4. The system for supplying sheets to a sheet gatherer as claimed in Claims 1-3, wherein said gripper mechanism and said feeder mechanism are driven at the same time and at the same speed.

5. The system for supplying sheets to a sheet gatherer as claimed in Claims 2 or 3, wherein said drive mechanisms are all operatively interconnected for separately and sequentially first operating said separator and next operating said gripper mechanism for gripping the groups of sheets.

6. The system for supplying sheets to a sheet gatherer as claimed in Claims 1-5, wherein said separator is a rotary member in rolling contact with a surface of said stack of sheets for rolling over said plurality of sheets to form said group thereof.

7. The system for supplying sheets to a sheet gatherer as claimed in Claim 6, wherein said rotary member is a brush having protrusions thereon for contacting said sheets.

8. The system for supplying sheets to a sheet gatherer as claimed in any one of Claims 1-7, wherein said stack is oriented with the sheets thereof in an upright orientation and having a surface of aligned edges of the sheets, and said separator being a rotary member in rolling contact with said surface in the direction of movement of said stack of sheets, and with said separator extending into the path of said aligned edges for preventing movement of said sheets in said stack without rotation of said separator.

9. The system for supplying sheets to a sheet gatherer as claimed in Claim 1, wherein said sheet gripper mechanism includes a circular member located in the path of movement of said stack of sheets and having a horizontal axis, and said separator being disposed adjacent said circular member for moving said plurality of sheets as a group against said circular member for giipping by said gripper mechanism.

1 0. The system for supplying sheets to a sheet gatherer as claimed in Claim 9, wherein said separator is a rotary member in rolling contact with a surface of said stack of sheets for rolling over said plurality of sheets to form said group thereof.

11. The system for supplying sheets to a sheet gatherer as claimed in Claim 9, wherein said gripper mechanism includes a sheet gripper movably disposed on said circular member, and drive mechanism operatively connected with said circular member for rotating and then stopping said circular member to a position to present said sheet gripper adjacent said group of the plurality of sheets.

12. The system for supplying sheets to a sheet gatherer as claimed in Claim 11, including a drive mechanism operatively connected to said separator and being operatively associated with said drive mechanism of said circular member for synchronizing the movement of said circular member and said separator.

13. A system for supplying sheets to a sheet gatherer and having a movable stack of sheets, a sheet gripper means movably disposed in the path of said stack of sheets for picking up the sheets from said stack of sheets and moving them away from the remainder of said stack of sheets, a sheet gatherer means, and a movable feeder means in sheet-movement communication with said sheet gatherer means and said gripper means for receiving the sheets from said gripper means and depositing the sheets on said sheet gatherer means, the improvement comprising a powered means disposed adjacent the leading end of said stack of sheets for separating a plurality of the sheets in said stack of sheets into a group separate from the trailing remainder of said stack of sheets, and said gripper means being movable into contact with said plurality of sheets for gripping said plurality of sheets for gripping said plurality of sheets and moving said plurality of sheets in a group form from said stack of sheets and to said feeder means.

14. A system for supplying sheets to a sheet gatherer, comprising the method steps of supporting and moving a main stack of sheets relative to a sheet gripper, separating a plurality of said sheets from said main stack and thereby have said plurality of sheets form a smaller stack of said sheets, and gripping and moving said smaller stack with said sheet gripper and away from the remainder of said main stack, and depositing said smaller stack of said sheets onto a sheet feeder mechanism and then onto a sheet gatherer.

1 5. The system for supplying sheets to a sheet gatherer as claimed in Claim 14, including the steps of monitoring the quantity of said sheets on said sheet gatherer, and separating and removing said smaller stack at a rate sufficient to supply a minimum quantity of said sheets at said sheet gatherer.

1 6. The system for supplying sheets to a sheet gatherer as claimed in Claim 14 or 1 5, including synchronizing the movements of separating said plurality of sheets and gripping said plurality of sheets.