GB2055085A - Separating sheet material - Google Patents

Abstract

A separating device (Fig. 1) for a stack (93) of record carrying items includes a device for supporting and feeding the stack through a feed path, a suction separating cylinder (90) disposed at the end of the feed path, and a retaining rake (92) overlying the feed path including a retaining face having a rough surface portion for engaging and restraining at least a part of the slack. A reverse rotating suction cylinder 91 also prevents double feed. <IMAGE>

Description

SPECIFICATION Device for separating record carrying items This invention relates in general to a device for separating record carrying items and, more particularly, to a new and useful separating device for separating a stack of paper sheets, such as bank notes or currency bills, which includes a feeder for feeding the stack through a feed path, a rotary separating cylinder for separating sheets from the stack, and a retaining rake for restraining the feed of at least a part of the stack by means of a rough surface portion.

A separating device is disclosed in United States Patent No. 3,976,291 in an arrangement for separating or singling out paper sheets, documents and similar recording media from a batch, with several of the sheets of documents initially being moved toward a separating slot. According to this art, a stack of items, to be separated, are fed through a so-called separating slot, where they are picked up by a separating cylinder and sequentially transferred to a conveying system.

A retaining rake is provided in the vicinity of the separation slot to assure that only a limited number of items can, at a time, pass into the separation slot. The rest of the stack is held back by the retaining rake, which is designed with sharp edges, at the entrance of the separation slot.

Experience has shown that an undesirable accumulation of sheets in the separation slot may be avoided to a large extent with a satisfactory paper quality. An almost continuous feeding of the items into the separation slot can be ensured by the special design and arrangement of the retaining rake. However, while treating stacks containing items of very dissimilar paper quality, i.e. worn down to different degrees, and, especially if the items are severely crumpled, it has been found that such items, particularly those having a leading edge bent away from a guiding wall, are retained by the sharp-edged portion of the retaining rake longer than necessary. Such items cause breaks in the continuity of the separation process and disturb the operation.

Another known retaining rake comprises continuously bent rods which form a stop for the leading edges of the stack of items. Such a design has the disadvantage that, with the exception of first-class paper quality, the leading edges of the stack receive a downwardly directed force component which eventually may lead to an undesirable accumulation.

SUMMARY OF THE INVENTION The invention is directed to a device for separating record carrying items which makes possible the continuous treatment of even stacks of items having very unequal paper qualities with fewer breaks in the continuity of operation.

Accordingly it is an object of the invention to provide a separating device for separating a stack of paper sheets, such as bank notes, including means for supporting and feeding the stack through a feed path, a separating cylinder disposed at the end of the feed path and having suction means for separating the sheets from the stack, a retaining rake overlying the feed path for restraining the feed of at least a part of the stack, the retaining rake being arranged at a spaced location from the separating cylinder to define a separating slot therebetween for the passage of the sheets, and the retaining rake having a retaining face facing the feed path which includes a surface portion for engaging at least a part of the stack. In a preferred embodiment the surface portion is a rough surface portion and is formed in a central part of the retaining rake's face.It is further preferred that the surface portion include a plurality of step-dash like serrations formed in the retaining face.

Treatment of very unlike qualities of paper has shown that the inventive design of the retaining rake in the zone of the separation slot results in a substantially faster and stronger feed of items into a separation slot.

To avoid wedging of the items in the separation slot or their displacement up the retaining rake. the thrust components occurring at the individual leading edges of the items are reduced by the roughened, preferably stepwise, serrated surface portion of the retaining rake to such an extent that in spite of the increased thrust, a segregating operation free from disturbances is insured.

The various features of novelty which characterize the invention are pointed out with particularity in the claims annexed to and forming a part of this disclosure. For a better understanding of the invention, its operating advantages and specific objects attained by its uses, reference is made to the accompanying drawings and descriptive matter in which a preferred embodiment of the invention is illustrated. It is a further object of this invention to provide a device for separating record carrying items, particularly sheets such as bank notes, which is simple in design, rugged in construction and economical to manufacture.

BRIEF DESCRIPTION OF THE DRAWINGS In the Drawings: Figure 1 is a side elevational view of a separation device, particularly broken away, utilizing a retaining rake in accordance with the invention; Figure 2 is a side elevation view of a retaining rake; and Figure 3 is a front view of a retaining rake.

DETAILED DESCRIPTION OF THE PRE FERRED EMBODIMENT Referring to the drawings in particular, the invention embodied therein comprises a device for separating record carrying items, particularly sheets of paper such as bank notes or the like. The separating device illustrated in Fig. 1 substantially comprises a separating cylinder 90, a retaining cylinder 91 with a retaining rake 92, an air conducting plate 94 for supporting a stack 93 of bills, such a bank notes or similar paper sheets, and feeding the individual bills to the separating cylinder 90, a pressure plate 95 for giving shape to the bill stack, and an air blast plate 99, secured to air conducting plate 94, having a plurality of air blast bores 96.

The stack of bills to be separated is supplied in the direction of arrow 100 by a double belt conveying system 30b which includes belts 102a and 102b and rollers 103.

As shown in Fig. 1, separating cylinder 90 rotates in the direction of arrow 104 on a fixed, concentric gate cylinder 1 05. Gate cylinder 105 is provided with a plurality of channels 106 which communicate with a recessed opening 107. The area of the opening 107 communicates through channels 106 to a vacuum pump (not shown). Separating cylinder 90 is provided with a single, axially extending row of suction ports 108 extending through a rubber strip 109. The rubber strip includes a surface which is flush with the outer cylindrical surface 110 of separating cylinder 90. The function of rubber strip 109 is to increase the friction while the bill is fixed thereto by suction.The area of the recessed area 107 of gate cylinder 105 is dimensioned and adjusted to communicate vacuum, as long as and in such a way, that each lowermost bill 11 9 to be separated is securely drawn and held by suction along its leading edge and released again after about a quarter turn of separating cylinder 90 in order to be transferred to belts 111, 11 2 of a conveying section 30c following the separating cylinder.

To prevent the withdrawal of two bills, the retaining cylinder 91, rotating on a fixed gate cylinder 113, is provided above separating cylinder 90 as shown in Fig; 1. The retaining cylinder 91 rotates in the direction of arrow 114, opposite to the direction of feed or separation. Retaining cylinder 91 is designed as a suction cylinder and carries suction rings 11 5 which are arranged side by side and have suction parts 11 6 uniformly distributed over the circumferences of the rings. The fixed gate cylinder 11 3 has only a single opening 11 7 which communicates through an axial cavity 11 8 with a vacuum pump (not shown).

Hence, all of the bills which are not to be separated, and already present in a separation slot 1 33 that is formed by the distance between the retaining rake 92 and separating cylinder 90, are attached by suction to the retaining cylinder, which rotates oppositely with respect to the direction of feed or separation, and are intermittently pushed back to stack 93. The retaining rake 92 insures that only the lowermost bills of stack 93 pass through the separation slot 1 33 to separating cylinder 90, and holds the other bills of the stack away from retaining cylinder 91.The retaining rake 92 is provided, on its rounded portion facing the entering stack 93, with a roughened surface in the form of a serration 87, as is best shown in Figs. 2 and 3, in order to prevent the passage of too many bills into the separation slot 1 33 which can cause a blockage or the sliding of the bills up the front of the retaining rake 92.

The serration 87 includes a plurality of steps. Each step is shaped so that the depth of the step is parallel to air conducting plate 94 and the height of each step is perpendicular thereto, that is, or parallel to the leading edge of stack 93. In this manner, the serration faces that are parallel to the leading edge of the stack absorb the feed force or thrust components which, without a serration, would be produced on the rounded portion of retaining rake 92. The bills are thereby prevented from sliding upwardly along retaining rake 92 and those bills which are positioned above separation slot 1 33 in front of retaining rake 92 are prevented from sliding down.

The number of steps of the serration may vary, depending upon the thickness and quality of the paper of the bills to be processed. In Figs. 2 and 3, for example, a serration 87 having five steps is shown by way of example.

As shown in Fig. 3, serrations 87 are provided only on the central portion of the retaining rake 92. The two outer ends of the retaining rake adjacent the central portion are designed without a serration, in order to prevent bills with dog ears (side edges turned up) from accumulating in front of retaining rake 92, and to guide such bills along the curved outer ends of the retaining rake into the separation slot. It may be further noted, that retaining rake 92 can be designed with parallel indentations 120, as shown in Fig. 3, for receiving projections formed on the adjacent side of pressure plate 95 facing retaining cylinder 91 and projecting beyond the leading edge of stack 93. This prevents the leading edges of the individual bills from accumulating on retaining rake 92 as the stack descends during the separating process.

In operation, a package or stack of bills is introduced from the double belt conveying system 30b onto air conducting plate 94.

System 30b is so dimensioned that its lower belts 102a run at a slightly higher speed than upper belts 102b. This displaces the bills at the bottom of the stack relative to those above, so that a wedge shaped leading edge of the bill stack is formed in the feed direction. Like the design of retaining rake 92 (serration 87), this provision also serves to prevent bills from becoming wedged in separation slot 1 33.

The introduction of the stack to the separating device is secured by a rake 1 35 which engages the lower conveyor roller 103, and by pressure plate 95 which engages the upper conveyor roller 103 in a comb-like manner. The stack is then advanced to retaining rake 92 or retaining cylinder 91 by its own inertia as well as by the effect of an air cushion provided along the air conducting plate. After the stack is introduced, the pressure plate 95 is lowered in the direction of arrow 137, so that the bill stack is shaped under a slight pressure which is then uniformly maintained during the entire feeding and separating operation.

In the course of introducing the stack, as noted above, the bills at the bottom of the stack are conveyed, due to a particular characteristic of air conducting plate 94, along the vertically extending mounting wall (not shown) disposed along one side of the air conducting plate, into separating slot 133, until their leading edges abut against suction rings 11 5 of retaining cylinder 91. Due to the air cushion of the air conducting plate 94, and the suction and feed effect produced thereby, the stack is now resting in a standby position in the separating device. A longitudinal edge portion of the lowermost bill of the stack, extends over the bevelled area (not shown) on air conducting plate 94, is bent down. The leading edge of the lowermost bill 119, in the feed direction, reposes with its underside on separating cylinder 90.As soon as the ports 108 of segregating cylinder 90 reach the recessed opening 107 of gate cylinder 105, the leading edge of lowermost bill 11 9 is drawn to the ports by suction. About at the same instant, air blast bores 96 of air blast plate 94 are pneumatically pressurized so that additional air is blown along the entire stack between the bill to be separated and the overlaying stack. The bill is thereby released from load by two air cushions and can easily be withdrawn from the stack. As soon as ports 108 have crossed the recessed opening 107 of gate cylinder 105, the vacuum at ports 108 is eliminated. The leading edge of the bill is thereby released from the separating cylinder and can freely enter the following conveying section 30c comprising belts 111, 11 2.

When the bill has been completely withdrawn from the stack, the air blown through air blast bores 96 if air blast plate 94 is interrupted.

This insures that the next bill to be segregated can deflect along its longitudinal edge onto bevelled portion of air conducting plate 94, under the suction effect which is created there.

An extension 92a (see Fig. 1) of retaining rake 92 may be used to facilitate the deflection of the separated bills and introduction of their leading edges into following conveying section 30c.

The bills remaining in the stack in each instance of separation are held back by retaining cylinder 91 and pushed back into the stack. The effective range of the retaining suction is limited to the clear width of opening 11 7 of gate cylinder 11 3 of retaining cylinder 91.

The inventive retaining rake, of course, may advantageously also be employed in connection with other segregating devices.

While a specific embodiment of the invention has been shown and described in detail to illustrate the application of the principles of the invention, it will be understood that the invention may be embodied otherwise without departing from such principles.

Claims (10)

1. A device for separating record carrying items of the type having a feeder, a retaining mechanism and a withdrawing mechanism, wherein a stack having a plurality of record carrying items is advanced through a feed path, by means of the feeder, to a separation slot, and the items which are not positioned in the separation slot are held back by means of a retaining rake, the retaining rake comprising an abutment face which is continuously curved toward the separation slot and includes a rough surface portion at the entrance of the separation slot, the items to be separated being positioned in front of the separation slot so that the superposed leading edges of the items offset in a wedge-like manner.

2. The device according to claim 1, wherein the rough surface portion of the retaining rake is formed with a step-like serration.

3. The device according to claim 2, wherein the serration is limited to the middle part of the retaining rake.

4. The device according to claim 1, further comprising a double belt conveying system provided at the end of the feed path remote from the separation slot, said belt conveying system having a lower belt supporting the bottom of the stack and an upper belt engaging the top of the stack, the lower belt being driven at a running speed which is higher than that of said upper belt to such an extent that the record carrying items of the stack being fed in the direction of the separation slot are moved toward the separation slot with their superposed leading edges offset in a wedge like manner.

5. A separating device for separating a stack of paper sheets, such as bank notes, comprising: means for supporting and feeding the stack through a feed path, a separating cylinder disposed at the end of the feed path and having suction means for separating the sheets from the stack, a retaining rake overlying the feed path for restraining the feed of at least a part of the stack, said retaining rake being arranged at a spaced location from said separation cylinder to define a separating slot therebetween for passage of the sheets, and said retaining rake having a retaining face facing the feed path including a surface portion for engaging at least a part of the stack.

6. The device according to claim 5, wherein said surface portion includes a plurality of step-like serrations formed in said retaining face.

7, The device according to claim 6, wherein said serrations are formed in a central part of said retaining face.

8. The device according to claim 5, further comprising conveying means for conveying said stack to said supporting and feeding means at the end of said feed path opposite said first mentioned end, said conveyor means having a first conveyor member being engageable with a first face of said stack and a second conveyor member spaced from said first conveyor member being engageable with an opposite face of said stack, said first and second members being movable at different speeds in the direction of said separation slot.

9. The device according to claim 8, wherein said surface portion includes a rough surface portion.

10. The device according to claim 9, wherein said rough surface portion is formed in a central part of said retaining face.