US3516687A

US3516687A - Assembly of sheets stapled to a backing member,and associated methods of installation

Info

Publication number: US3516687A
Application number: US722770A
Authority: US
Inventors: John D Langwell
Original assignee: Individual
Current assignee: Individual
Priority date: 1968-04-19
Filing date: 1968-04-19
Publication date: 1970-06-23
Anticipated expiration: 1987-06-23

Description

June 23, 1970 J. D. LANGWELL- 3,516,687

ASSEMBLY OF SHEETS STAPLE D To A BACKING MEMBER, AND ASSOCIATED METHODS OF INSTALLATION Filed April 19, 1968 Wh ll 1 5 4 z FIG.2

INVENTOR. JOHN D. LANGWELL Fab;

ATTORNEYS United States Patent O ABSTRACT OF THE DISCLOSURE An assembly of sheets mounted on a backing member by a loop staple having one leg passing through the sheets and the other leg passing through a plug which is held between the bridge of the staple and the backing member.

BACKGROUND OF THE INVENTION Field of the invention 1n1s invention relates to the installation of a staple to secure a plurality of sheets against a backing member to form a pad from which the sheets are removable by being torn from the staple.

Description of the prior art It is well known to employ staples to secure a plurality of sheets to a backing member. It is also known to form the staple with a particular shape to enable the sheets to be loose on the staple and thereby be removable from the staple by being torn therefrom. Moreover, the shape is such as to keep the staple anchored to the backing member after some sheets are removed. The requirement of such special shapes for the staples complicates their manufacture and installation and greatly increases the cost of the assembly.

SUMMARY OF THE INVENTION An object of the invention is to provide a staple assembly of the above character in which the staple is of standard loop form and hence does not increase the cost of the assembly.

Another object of the invention is to provide suitable means, of an inexpensive nature, which can be installed together with the staple and be eifective to keep the staple anchored to the backing member after removal of some sheets.

Another object of the invention is to provide a method of assembly of sheets and staples to a backing member with the aforesaid means which is simple and reliable.

Yet another object of the invention is to employ a resilient plug in a staple assembly of the above type in order to utilize the resilience of the plug to enhance the anchoring of the staple to the backing member after some sheets have been removed.

In accordance with the invention, a staple body of loop form is secured to a backing member to hold a stack of thin sheets against the backing member. One leg of the staple body passes through the sheet and is clinched to the backing member, and the other leg of the staple body passes through a plug and is also clinched to the backing member. The plug is interposed between the backing member and a bridge of the staple body joining the two legs, the plug serving to hold the staple body anchored to the backing member, particularly after removal of sheets.

Advantageously, the plug may be constituted of a flexible material which is compressed between the staple body ice and the backing member. This ensures the anchoring of the staple body to the backing member right up to the removal of the last sheets of the stack.

In further accordance with the invention, a method is provided for the assembly of the sheets to the backing member using staples and plugs of the type described hereinabove. According to this method, one leg of a staple body is passed through the stack of sheets and backing member and clinched against the backing member while simultaneously the other leg of the staple body is passed through a plug and the backing member and clinched against the backing member.

The method is applicable to the successive installation of staples through stacks of material on respective backing members to mass produce pads in succession. In this respect plugs are fed in synchronization with stacks of sheets on respective backing members, and staples are driven into the sheets, plugs and backing members to produce repeated numbers of pads.

BRIEF DESCRIPTION OF THE DRAWING FIG. 1 is a plan view of a pad according to the invention;

FIG. 2 is a sectional view on enlarged scale taken along lines 2-2 in FIG. 1;

FIG. 3 is a plan view of a portion of a pad according to a modified version of the invention;

FIG. 4 is a sectional view on enlarged scale taken along lines 4-4 in FIG. 3 g and FIG. 5 is a diagrammatic side elevation view of apparatus for producing a stapled pad according to the invention.

DETAILED DESCRIPTION In FIG. 1 of the drawing there is seen a pad 1 which includes a rigid backing member 2 constituted, for example of cardboard or the like, and a stack of sheets 3 of flexible material, such as paper, mounted on the backing member by a pair of staples 4 at one edge of the stack. The sheets of the stack are removable from the pad by being torn from the staples.

In order to preserve the anchoring of the staples to the backing member, after removal of sheets from the stack, plugs 5 are employed. Without the plugs 5, the staples 4 would be free to pivot with respect to the backing member after some sheets 3 have been removed. As a consequence, the staples readily separate from the backing member under the action of, and by the removal of the sheets. This frequently occurs after removal of only a relatively few sheets, and therefore the pad becomes dismantled and the major portion of the stack is unused.

The plugs 5 serve to anchor the staples to the backing member by preventing the harmful pivoting movement of the staples with respect to the backing member. In operation, the plugs act to hold the staples in a fixed position on the backing member, thereby ensuring the permanent anchoring of the staples to the backing memher.

As seen in FIG. 2, each staple is constituted as a continuous length of material of loop form with two spaced leg portions -6 connected by a bridge portion 7. One leg of the staple passes through the stack of sheets 3 and is clinched to the backing member 2. The other leg of the staple passes through the plug 5 and is clinched to the backing member.

It is important that the plug 5 have a relatively tight fit between the bridge portion 7 of the staple and the backing member 2. Without such a fit, the staple will be free to wobble with respect to its backing member, particularly when the sheets are torn from the staples and this enlarges the holes in the backing member through which the staples pass. Eventually one of the legs of the staple will pull through the enlarged holes of the backing member and the connection of the staple to the backing member will be destroyed.

In order to provide a tight fit of the plug 5, the invention contemplates several solutions. In a first, the plugs are relative rigid and have a height corresponding to the length of legs 6. Hence when the plugs are installed with the staple they will be tightly fitted in place. However, this requires the need for plugs of different heights for the various heights of staples for different thickness pads. This is generally disadvantageous, since it requires maintaining a stock of different size plugs. Moreover, it is necessary to carefully distinguish the plugs of differene sizes, since by casual inspection two adjacent sizes may appear to be similar. Different colors may be used for different sized plugs but this increases their cost. Thus, this embodiment will generally be used for staples of only one size.

It has been found that an effective tight fit of the plugs can be obtained by making the plugs of resilient material, such as rubber, plastic or the like, and compressing the plug between the bridge portion 7 and the backing member 2. This not only results in a tight fit for the plug, but the resilience of the plug, and its compressed state in the assembly, insures a tight fit and consequent anchoring of the staple to the backing member down to the removal of the last sheet of the stack. The resilient plug may be of suitable size, in its uninstalled condition, as to be usable with a wide range of staple heights for various pad thicknesses. Thus, only one, or perhaps two, sizes of plugs are necessary for the entire range of pad thicknesses and staple heights. Moreover, these two sizes of plugs will be obviously different by visual inspection and hence the likelihood of installing plugs of the wrong size is remote.

As shown in FIGS. 1 and 2 the plugs are of cylindrical shape. This shape has great value since the plugs require no angular orientation in their installation. Moreover, such plugs have a wide bearing surface for resting on the backing member, and the bridge portions 7 lie fiat on the upper surfaces of the plugs. The diameter of the plugs must be considerably greater than the diameter of the wire of the staple and the ratio of such diameters will be at least a value of 3 and generally much higher. Preferably, the plugs will bear against the edges of the sheets 3, in the manner as shown in FIG. 3 for plugs a of a modified version. In this respect, it is to be understood that the plugs 5 may bear against the edges of sheets 3 even though shown spaced therefrom in FIG. 2.

The plugs 5a in FIGS. 3 and 4 have a tubular shape and the staples pass diametrically therethrough. The shape of the plugs 5a promotes their flexibility. As has been described hereinabove, it is preferred that one end of the plug abut the edges of sheets as shown in FIG. 3. This aids in maintaining the sheets in a fixed position on the pads and tends to relieve the load on the staple. The material of plug 5a is also preferably resilient and consequently this plug undergoes a flattering deformation upon installation and subsequent restoration which promotes the pre-stress action on the staple.

It is preferable that the staple pierce the material of the plug when it is installed, and for this reason the plug material should be readily pierceable by the staple leg. The rubber and plastic materials, which are preferred for their resilience, are also suited for being pierced by the staple. Hence these materials are greatly advantageous. However, it is also possible for the plugs to be pre-formed with axial bores and for the staple legs to pass through such bores.

FIG. 5 schematically shows the installation of staples for formation of pads. In FIG. 5 are seen a staple head and an anvil 11 positioned therebeneath. Backing members 2 each with a stack of sheets 3 thereon are fed in succession by a suitable mechanism (not shown) onto the anvil 11 into a predetermined position beneath the head 10. A supply tube 12 for a vertical stack of plugs 5 is positioned adjacent head 10. A reciprocally movable arm 13 operates in synchronization with the mechanism which feeds the backing members and sheets to the head, such that the plugs are displaced into position on each backing member at a location in alignment with the leg of its associated staple. The staple head then drives a staple into the plug, sheets, and backing member to form a pad as seen in FIG. 5. The pad is removed from beneath the head by a suitable device (not shown) and the above described operation is repeated successively to produce repeated numbers of pads.

Numerous modifications and variations of the disclosed embodiments of the invention will now be apparent to those skilled in the art without departing from the scope and spirit of the invention as defined by the appended claims.

Thus by way of example, a greater or lesser number of staples may be installed at the edge of each stack of sheets of each pad as dictated by the size of the pad.

What is claimed is:

1. An assembly comprising a backing member, a staple body secured to said backing member for holding a stack of thin sheets of material against said backing member such that the sheets of material are removable by being torn from the staple body, said staple body being constituted as a continuous length of material of loop form with two spaced leg portions which penetrate said backing member and are secured thereto, and a bridge portion between the leg portions extending in spaced relation from the backing member, one of said leg portions passing through the stack of sheets, and a plug engaged with the other of the leg portions and extending between the bridge portion and the backing member for anchoring the staple body to the backing member, said plug serving to hold the staple body anchored to the backing member after removal of sheets.

2. An assembly as claimed in claim 1 wherein said plug is constituted of a material in which said other leg of the staple body is pierceable.

3. An assembly as claimed in claim 2 wherein the plug material is flexible.

4. An assembly as claimed in claim 1 wherein said plug is of cylindrical shape and said other leg of the staple body passes axially therethrough.

5. An assembly as claimed in claim 1 wherein said plug is constituted of flexible material which is axially compressed between said bridge portion and the backing member.

6. An assembly as claimed in claim 1 wherein said plug is of tubular shape and said other leg of the staple body passes diametrically therethrough.

7. An assembly as claimed in claim 1 wherein said plug is in abutment with the stack of sheets.

8. An assembly as claimed in claim 1 wherein said plug has a bore through which said other leg of the staple body passes.

References Cited UNITED STATES PATENTS 9/1932 Lawson 282-22 JEROME SCHNALL, Primary Examiner US. 01. X.R.