US3707418A

US3707418A - Method of binding

Info

Publication number: US3707418A
Application number: US81356A
Authority: US
Inventors: Gopal C Bhagat; Joseph N May
Original assignee: Xerox Corp
Current assignee: Xerox Corp
Priority date: 1970-10-16
Filing date: 1970-10-16
Publication date: 1972-12-26
Anticipated expiration: 1989-12-26
Also published as: NL7114186A; GB1359338A; DE2151286A1; CA974723A

Abstract

A METHOD OF BINDING A QUANTITY OF SHEETS TOGETHER IN A STACK IN WHICH INDIVIDUAL SHEETS TO BE BOUND ARE ASSEMBLED IN OVERLYING STACKED RELATINSHIP WITH EACHSHEET HAVING ONE EDGE THEREOF UNIFORMLY POSITIONED ALONG A COMMON PLANE. A BEAD OF MOLTEN RESINOUS MEATERIAL IS THEN APPLIED TO THE EDGES OF THE SHEETS ALONG THE COMMON PLANE. THE BEAD OF RESINOUS MATERIAL IS THEN FLARED TO EXTEND FROM THE EDGES IN THE COMMON PLANE OVER PORTIONS OF THE UPPERMOST AND LOWERMOST SHEETS IN THE STACK. THE RESINOUS MATERIAL IS THEN SOLIDIFIED IN THE FLARED CONFIGURATION TO PROVIDE A BINDING FOR THE SHEETS ALONG THE UNIFORMLY POSITIONED EDGES.

Description

cs. c. BHAGAT ET AL 3,707,418

METHOD OF BINDING Dec. 26, 1972 Filed Oct. 16. 1970 INVENTORY GOPAL C. BHAGAT BY JOSEPH 5: MAY

ATTORNEY United States Patent US. Cl. 156245 3 Claims ABSTRACT OF THE DISCLOSURE A method of binding a quantity of sheets together in a stack in which individual sheets to be bound are assembled in overlying stacked relationship with each sheet having one edge thereof uniformly positioned along a common plane. A bead of molten resinous material is then applied to the edges of the sheets along the common plane. The bead of resinous material is then flared to extend from the edges in the common plane over portions of the uppermost and lowermost sheets in the stack. The resinous material is then solidified in the flared configuration to provide a binding for the sheets along the uniformly positioned edges.

BACKGROUND OF THE INVENTION This invention relates generally to sheet binding and more particularly to a method for binding a quantity of sheets together in a stack.

Numerous arrangements have heretofore been proposed for use in joining or binding a plurality of sheets together in a stack. Perhaps the most common method of sheet binding to date involves the use of a metallic U-shaped staple. Such staples are generally formed from drawn wire which are driven under pressure through a stack of sheets and then bent or clinched on the bottom side of the stack. Various mechanical arrangements have therefore been devised for forming the staples into the characteristic U- shape as well as specific arrangements for inserting and tomoving the wire staples from a stack.

While the use of wire staples has generally proven satisfactory as a means of joining or binding a plurality of sheets together in a stack, there have nevertheless been certain disadvantages associated with the use of such binding or fastening arrangements. For example, the wire staples often times have a tendency to buckle or bend during the process of being driven into the stack of sheets. Also, in many instances the wire staples are improperly bent or clinched on the under side of the stack. When either of these occur, the wire staple provides a less than effective means of binding together the sheets in the stack. When an improperly inserted staple is detected, the wasted staple must therefore be removed and the process repeated until a properly driven and clinched staple is obtained. This results in unnecessary mutilation of the sheets in the stack as well as consuming unnecessary operator time in the binding operation.

In many instances, an improperly inserted staple may not be detected in the binding operation. This is particularly true in the case of improper clinching on the under side of the stack. This results in a loosely held stack of sheets which is susceptible to loss of sheets from the stack. In addition, such improperly clinched staples can also cause damage to underlying stacks of sheets. Moreover, such improperly clinched staples pose the inherent possibility of effecting damage to clothing as well as injury to a person handling such improperly bound stacks of sheets.

Another method of binding which has been utilized is that which has been characterized as adhesive binding. According to at least one method of adhesive binding, sheets or signatures are collected and carried forward in an upright position with the back or edges to be bound sup- 3,707,418 Patented Dec. 26., 1972 ICC ported downwardly by means of clamps attached to a conveyor system. In the case of signatures, the folded portions thereof may be cut off to leave all of the sheets separate in the assembly. The edge of the back may then be coated with an adhesive material and spread to a uniform thickness thereon by suitable means, such as a roller applicator member for example. A permeable flexible backing may then applied to the adhesive material and a subsequent coating of adhesive material applied thereto to complete the binding arrangement after drying of the adhesive material has taken place.

Another form of adhesive binding involves the use of special tapes having adhesive materials coated thereon. The adhesive material on such tapes is usually normally in a non adhesive state and is activated to an adhesive state just prior to application through the use of heat or solvents. When applied to the back of a group of sheets these adhesive coated tapes provide the binding mechanism by which sheets are held together.

While previous binding arrangements have found application in various binding operations, there nevertheless has existed a need for an improved, more effective and more efiicient method for binding sheets together in a stack.

SUMMARY OF THE INVENTION Accordingly, it is an objective of the present invention to provide an improved method of binding a quantity of sheets together in a stack.

It is another object of the present invention to provide an economical and effective method of binding a quantity of sheets together in a stack.

It is still another object of the present invention to provide a novel method of binding a quantity of sheets together in a stack which exhibits excellent holding capability.

It is a further object of the present invention to provide a method of binding a quantity of sheets together in a stack which results in an attractive fastening arrangement.

It is yet a further object of the present invention to provide a novel method of binding a quantity of sheets together in a stack which is effective and reliable in maintaining the integrity of the bound material.

These and other objects of the present invention are attained by assembling the individual sheets to be bound in overlying stacked relationship with each sheet having one edge thereof uniformly positioned along a common plane, applying a bead of molten resinous material to the edges of the sheets along the common plane, flaring the bead of resinous material from the edges to extend over portions of the uppermost and lowermost sheets in the stack and solidifying the resinous material in the flared configuration.

Other objects of the invention will become readily apparent to those skilled in the art in view of the following detailed disclosure and description thereof, especially when read in conjunction with the accompanying drawings.

BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is an end view showing an assembled stack of sheets which are to be bound together.

FIG. 2 is an end view showing an assembled stack of sheets with a bead of resinous material applied to the edges of the sheets in the stack.

FIG. 3 is an end view showing the stack and bead of FIG. 2 being inserted into a mold.

FIG. 4 is an end view showing the stack and head of FIG. 2 with the dies of the mold of FIG. 3 closed.

FIG. 5 is an end view showing an alternate configuration of the molding dies of FIGS. 3 and 4.

FIG. 6 is an end view showing a finished bound stack of sheets according to the arrangement of FIGS. 1-4.

DESCRIPTION OF THE PREFERRED EMBODIMENTS Referring to FIGS. 1-4 of the drawings,there are illustrated various steps in the method of binding as contemplated by the present invention. As illustrated therein, a quantity of sheets 10 which are to be bound together are assembled in overlying stacked relationship. In the stacked relationship one edge of each of the individual sheets 10 is uniformly positioned along a common plane such as the plane of the stack as seen at the bottom of FIG. 1. Various known sheet handling apparatus may be employed to produce this relationship such as sheet stackers, sheet joggers or other similar types of sheet handling devices.

With the individual sheets 10 thus assembledand positioned, a bead of molten resinous material is applied to the edges of the sheets 10 along the common plane or spine While any suitable material may be utilized in the binding method as contemplated by the present invention, a resinous material is preferred. Although the specific material chosen may vary with the particular application, the material according to a preferred embodiment should generally exhibit the characteristic of being molten or flowable and of solidifying when used in accordance with the present invention. Typical materials include thermoplastic and thermosetting resins, metals and rubber. Typical thermoplastic materials include polymers and copolymers of polyolefins such as polyethylene, polypropylene, chlorinated polyethylene, chlorosulfonated polyethylene; polymers and copolymers of vinyl and vinylidenes such as polystyrene, polymethylstyrene; acrylic polymers such as polymethyl methacrylate, polyacrylic acid, polyacrylonitrile; polyvinyl esters such as polyvinyl acetate, polyvinyl alcohol, polyvinyl butyral, polyvinyl chloride, polyvinyl carbazole, polyvinyl ethers, polyvinyl ketones; polymers and copolymers of fluorocarbons such as polytetrafluoroethylene, polyvinyl fluoride, polyvinylidenefluoride, polychlorotrifluoroethylene; and polymers and copolymers of heterochain thermoplastics including polyamides such as polycoproloctamo, polyhexamethylene adipamide; polyesters such as polyethylene terephthalate, polyurethanes; polypeptides such as casein, zein; ether and aeetal polymers such as polyoxymethylene, polyglycol, polysulfides, polycarbonates; cellulosic polymers such as viscose, cellophane, cellulose acetate. Typical thermosetting resins include polymers and copolymers of phenolic resins such as phenol-formaldehyde, phenol-furfural, resorcinol formaldehyde; polymers and copolymers of amino resins such as urea-formaldehyde, melamine-formaldehyde; polymers and copolymers of polyester resins; polymers and copolymers of epoxy resins; polymers and copolymers of urethanes; polymers and copolymers of silicone resins; and polymers and copolymers of miscellaneous resins including alkyd resins, alkyl resins, and furan resins.

The bead of molten material may be applied to edges of the sheets in the stack by any suitable means. Various known arrangements by which the molten material may be applied include dipping the edges of the sheets in a reservoir containing the molten material as well as applicator methods employing rollers, wheels, brushes and sprays. The molten material when applied to the edges of the sheets adheres thereto by wetting the edges of the sheets and according to the preferred arrangement should be applied in suflicient quantities to form a large bead 15 as shown in FIG. 2.

After the head 15 of molten resinous material has been applied to the edges of sheets 10 along the spine or common plane, the bead 15 of molten material is flared from the edges in the common plane over portions of the uppermost and lowermost sheets in the stack. This may be ac- 4. complished in a variety of ways. However, flaring by the use of molding dies is preferred.

One arrangement by which the bead of molten material may be flared from the edges of the stack in the common plane over portions of the uppermost and lowermost sheets in the'stack is by the use of a die arrangement such as that shown in FIGS. 3 and 4. As illustrated therein, dies 11 and 12 having respectively associated-

molding surfaces

13 and 14 are mounted in opposed relationship for reciprocal movement on'base member 16. According to this arrangement, a portion of the surface of basemember 16 over which die members 11 and 12 are reciprocably movable also serves as a portion of the total molding surface for the flaring operation.

According to a preferred arrangement, die members 11 and 12 are resiliently biased by spring members or other suitable biasing means in a direction toward each other on base member 16. Thus, a stack of sheets 10 with bead 15 of molten material applied theretomay be inserted into the die arrangement of FIGS. 3 and :4 'with'die members 11 and 12 engaging the uppermost and lowermost sheets of the stack respectively. Suitable means may also be provided for effecting movement of one'or both of the die members Hand 12 against the action of the respectively associated spring members to a position such as shown in FIG. 3 prior to insertion of the stack thereby permitting ready insertion of the stack 10 into the molding arrangement for the flaring operation. I

With the stack 10 inserted between dies 11 and. 12 over base member 16, the dies 11 and 12 are allowed to be moved under the influence of the respectively associated spring members to contact the respective uppermost and lowermost sheets in the stack. In this position as may be seen in FIG. 4, portions of the head 15 are forcedoutwardly and upwardly over the uppermost and lowermost sheets in the stack. It will be appreciated that during the flaring operation, the stack of sheets 10 is spaced a predetermined distance from base member 16 so as to provide a finite thickness of material along the edges of the sheets 10. It will also be appreciated that as a result of the configuration of the molding surfaces 13 and 14 a finite thickness of the flared material is also provided along the uppermost and lowermost sheets in the stack. The combined action therefore, of molding surfaces 13 and 14 in conjunction with a portion of the surface of base member 16 serve to flare bead 15 from the edges of the sheets 10 as seen in FIG. 2 to extend in a predetermined thickness around the spine or common plane and over portions of the uppermost and lowermost sheets in the stack'as seen in FIG. 4.

With the stack of sheets 10 supported between molding surfaces 13 and 14 and over base member 16, the stack may be transported along the length thereof through the die members by any suitable conveying or supporting arrangement. As the stack 10 is thus transported, bead 15 will be flared outwardly and upwardly from the common plane or spine of the stack over the uppermost and lowermost sheets in the stack along the length of the stack 10.

After the flaring or molding operation, has been completed, the molten material is solidified in the flared configuration. For most materials this is accomplished as the material is cooled from an elevated temperature to normal ambient room temperature. For other materials this may be accomplished by evaporation of plasticiiers or solvents from the molten material in the flared configuration.

As may be seen from FIG. 6 the binding arrangement when performed according to the described method yields a stack of sheets 10 which are held together by means of the solidified resinous material. The resinous material in the flared configuration adheres to the edges of the individual sheets along the spine or common plane and in the generally U-shaped configuration of predetermined thickness, engages both the uppermost and lowermost sheets in the stack to provide an efiective, reliable, and

attractive binder for supporting the sheets in a stack or book.

It should be appreciated that the resinous material may be flared into various configurations other than the configuration illustrated in FIGS. 1-4 and 6, for example, the configuration shown in FIG. 5. In the configuration of FIG. 5 a greater quantity of resinous material is retained along the edge portion of the stack to reinforce the resulting binding arrangement along the edges of the \sheets. Other configurations may equally provide an effective and reliable binding arrangement. It should also be appreciated that the flaring operation may be accomplished by means other than the molding arrangement specifically described in connection with FIGS. l-4 and that means many be associated with the die members for scraping or removing excess amounts of the resinous material.

From the foregoing arrangement it will therefore be appreciated that the binding method as contemplated by the present invention may be implemented in a variety of embodiments which provide economical, effective and reliable means for binding a quantity of sheets together in a stack.

While the binding method as contemplated by the present invention has been described with reference to preferred arrangements, it will be generally understood by those skilled in the art that various changes may be made and equivalents may be substituted for elements thereof without departing from the true spirit and scope of the invention.

What is claimed is: 1. A method of binding a plurality of sheets together in a stack comprising,

assembling individual sheets in overlying stacked relationship with each sheet having one edge thereof uniformly positioned along a common plane,

applying a bead of molten resinous material to the edges of said sheets along said common plane,

subjecting said uniformly positioned edges and said applied bead of resinous material to the internal molding surfaces of a die member to flare portions of said resinous material from said edges over portions of the uppermost and lowermost sheets in said stack, and

solidifying said resinous material in said flared configuration to form a binding for said sheets along said uniformly positioned edges.

2. A method of binding a quantity of sheets together in a stack comprising,

flaring portions of said bead of resinous material from said edges over portions of the uppermost and lowermost sheets in said stack by subjecting said bead to the internal molding surfaces of a die member, and

3. A method of binding a quantity of sheets together to form a book comprising,

assembling the individual sheets in overlying stacked relationship with each sheet having one edge thereof uniformly positioned along a common plane,

subjecting said uniformly positioned edges and said applied bead of resinous material to a die having a molding surface of a predetermined configuration to produce a flow of said resinous material within said die over a portion of the surfaces of the uppermost and lowermost sheets in said stack adjacent the uniformly positioned edges, and

solidifying said resinous material in a configuration conforming to said die to form a binding for said sheets along said uniformly positioned edges.

References Cited UNITED STATES PATENTS 2,558,405 6/ 1951 Weinstein 28222 R 2,922,417 1/1960 Bradley et al 156245 X FOREIGN PATENTS 902,209 8/ 1962 Great Britain l56295 RICHARD D. LOVERING, Primary Examiner US. Cl. X.R.

156292, 295, 305; 16l149, 268; 2828 R, 22 R, DIG. 2