US3634906A

US3634906A - Typist{3 s or draftsman{3 s eraser

Info

Publication number: US3634906A
Application number: US18082A
Authority: US
Inventors: Herbert G Lehmann
Original assignee: Individual
Current assignee: Individual
Priority date: 1970-03-10
Filing date: 1970-03-10
Publication date: 1972-01-18
Anticipated expiration: 1989-01-18

Abstract

A typist''s and draftsman''s eraser comprising an elongate slab of rubberlike erasing material and a semirigid holder structure therefor, the latter having channelled sections which grip the slab in such a manner as to frictionally seize the same and prevent slippage. The slab is of substantially rectangular transverse cross section, providing a thin elongate erasing surface. The holder structure provides a stiff body in which to house and grip the slab, by virtue of its oppositely disposed channel sections. Additionally, the holder structure provides a means for comfortably grasping the erasing device in the hand. As the slab end is worn in use, it can be easily and quickly advanced any number of times to maintain the desired degree of protrusion, all without disassembling the holder or releasing any clamps. Removal of an exhausted erasing slab and subsequent replacement with a new one is similarly easily accomplished. Two separate slabs may be employed in place of a single slab, in which case two functional erasing ends are provided.

Description

United States Patent Lehmann 51 Jan. 18, 1972 154] TYPISTS 0R DRAFTSMANS ERASER Herbert G. Lehmann, 5 Kent Road, Easton, Conn. 06612 [22] Filed: Mar. 10, I970 [21] Appl.No.: 18,082

[72] Inventor:

[52] US. Cl. ..15/434, 24/81 R [51] Int. Cl ..1B43l 19/00 [58] Field of Search ,.15/424-434, 105.51, 15/105.52, 105.53; 401/88, 91, 92, 95; 24/81 R [56] References Cited UNITED STATES PATENTS 193,795 7/1877 Cleveland ..l5/425 423,238 3/1890 Fowler 15/427 799,618 9/1905 St. John..... 15/433 1,098,287 5/1914 Moon ....15/432 1,248,988 12/1917 Antler ....15/432 1,569,742 1/1926 Goerling 1 5/428 3,262,425 7/1966 Waugh ..15/431 FOREIGN PATENTS OR APPLICATIONS 17,914 8/1904 Great Britain ..15/425 2/1908 Great Britain ..15/434 8/1909 GreatBritain ..15/434 Primary Examiner-Daniel Blum Att0rney-H. Gibner Lehmann [5 7] ABSTRACT A typists and draftsmans eraser comprising an elongate slab of rubberlike erasing material and a semirigid holder structure therefor, the latter having channelled sections which grip the slab in such a manner as to frictionally seize the same and prevent slippage. The slab is of substantially rectangular transverse cross section, providing a thin elongate erasing surface. The holder structure provides a stiff body in which to house and grip the slab, by virtue of its oppositely disposed channel sections. Additionally, the holder structure provides a means for comfortably grasping the erasing device in the hand. As the slab end is worn in use, it can be easily and quickly advanced any number of times to maintain the desired degree of protrusion, all without disassembling the holder or releasing any clamps. Removal of an exhausted erasing slab and subsequent replacement with a new one is similarly easily accomplished. Two separate slabs may be employed in place of a single slab, in which case two functional erasing ends are provided.

1 Claims, 8 Drawing Figures TYPISTS 01R IDRAIFTSMANS ERASER No cross references to related applications.

BACKGROUND This invention relates to magazine-type erasing devices, and more particularly to devices of this type wherein the erasing element is in the form of a flat slab. The present invention involves improvements in the erasing device illustrated and described in my U.S. Pat. No. 2,559,884, in which a metallic body or holder was employed to house a slab of erasing material, and a clamping means utilized to insure that the slab was held against slippage within the holder during use. This construction had several disadvantages. The angular edges of the metal holder tended to cut into the fingers of the user, particularly after prolonged use of the device. In its normal position, the clamping means acted in such a way as to slightly compress the slab in order to hold the latter stationary; this tended to cause binding whereby the clamp was difficult to retract when one desired to advance or replace the slab. Additionally, the holder construction being a sheet metal stamping was expensive in relation to ordinary eraser devices in use today. Finally, only a single erasing element could be employed, whereby only one end of the eraser displayed usable erasing material. These various details constituted distinct disadvantages, which limited the usefulness of the eraser.

SUMMARY The above drawbacks and disadvantages of this prior erasing device are obviated by the present invention, which has for one of its objects the provision of an improved erasing device of the flat-slab type, which is especially easy and comfortable to use, economical to produce, and simple in its construction. This objective is accomplished by the provision of a novel holding structure for the slab, constituted as one or more plastic extrusions so arranged as to jacket the slab in the manner of a rigid handle. The holder structure can be a single piece, or it can be two separate pieces. In each case, the structure comprises a pair of channel sections which frictionally grip opposite longitudinal edges of the slab. When the user grasps the erasing device, his grip is applied to the holder structure in such a manner that the latter more securely grips the erasing slab, while at the same time that it imparts a desirable rigidity to the same.

Another object of the invention is to provide an erasing device wherein the holder can be manufactured from an extrusion of plasticlike material. A further object of the invention is to provide an improved erasing device wherein the erasing element or slab can be readily advanced or even completely replaced without disassembly of the holder or release of any clamps. Yet another object of the invention is to provide a novel erasing device having usable erasing material protruding from both ends of the holder, thereby increasing the devices flexiblity and usefulness.

Other features and advantages will hereinafter appear.

In the accompanying drawings, illustrating several embodiments of the invention:

FIG. I is a perspective view of the erasing device, showing the holder supporting two erasing slabs.

FIG. 2 is a top plan view ofthe erasing device of FIG. 1.

FIG. 3 is a side elevational view of the erasing device.

FIG. 4 is a bottom plan view of the erasing device.

FIG. 5 is a transverse section taken on line 5-5 of FIG. 1.

FIG. 6 is a transverse section similar to that of FIG. 5 but illustrating another embodiment of the invention.

FIG. 7 is a transverse section similar to that of FIG. 5 but illustrating still another embodiment of the invention.

FIG. 8 is a perspective view of the erasing device held in the hand, as it would be during use.

Referring to FIGS. l-5, the improved erasing device of the invention comprises a holder designated generally by the nu meral 20, and a pair of

slabs

22, 24 of erasing material supported in the holder.

Each of the

slabs

22, 24 is identical to the other, and accordingly only one will be described in detail. The slab 22 is of rectangular configuration and has a pair of oppositely located broadsides 26, a pair of relatively narrow opposite longitudinal sides 28, and a pair of opposite end surfaces 30. I have found that a desirable size for the slab 22 is approximately inch wide by 3/l6-inch thick by IVs-inch long. Preferably the rubberlike substance of the slab includes fine grits to facilitate the erasing action, particularly where a new typewriter ribbon is being used to make the copy, or where inked lines are to be erased.

In accordance with the present invention there is provided, in conjunction with the slabs 22, 24 a novel and improved holding device which is extremely simple and inexpensive to produce, comfortable to hold and easily operated, yet sturdy and reliable in use.

In FIGS. 1-5 this holding device comprises two separate identical hollow-structured

members

32, 34, only one of which need be described. The member 32 is constituted of thin semirigid or resilient sheet material, and may be ad vantageously formed as a plastic extrusion. It comprises a pair of spaced

flanges

36, 38 and a connecting web 40. The outer longitudinal face 42 of the connecting web 40 constitutes the outer wall of the holder structure 20. The hollow

structural members

32, 34 firmly frictionally seize the opposite broadsides 26 of the

slabs

22, 24 by means of their edge portions (44, 46 of the member 32). The member 32 is preferably so constructed as to constitute a tight fit with the

slabs

22, 24 only along its

edge portions

44, 46 as shown in FIG. 5. To prevent binding of the

slabs

22, 24 within the

members

32, 34, the base portions of the spaced flanges (36, 38 of the member 32) adjoining the webs thereof are not in pressing contact with the

slabs

22, 24. This is clearly indicated in the figure, and is accomplished by making the

spaced flanges

36, 38 converge slightly toward the longitudinal centerline of the

slabs

22, 24. thus achieving a tight gripping action with a minimum of binding. When seated properly, the opposite narrow sides 28 of the slab 22 contact the interior portion 48 of the connecting web 40, thus enabling the slab to be firmly seated in the holder member.

When the erasing device is grasped in the hand as shown in FIG. 8, the resultant pressure on the

holder members

32, 34 tends to prevent slippage of the

slabs

22, 24 in the holder. It has been found that virtually no slippage occurs during use when the device is held in this manner.

When either of the erasing slabs (22 or 24) becomes worn in use, it may be easily advanced by grasping the remaining exposed portion with one hand, and gently forcing the

holder members

32, 34 back until the desired protrusion is obtained. Or, one holder. member may be held while the other is retracted, and then the other held while the first is retracted. The 32, 34 may be retracted simultaneously, or one at a time, the latter being generally easier. Replacement of an exhausted slab can readily be effected by pulling the

members

32, 34 laterally off of the slabs and applying them to new slabs.

FIG. 6 depicts another embodiment of the invention, wherein a two-piece holder construction is shown again. The channelled

members

50, 52 are identical to each other; only one is described in detail. The member 50 comprises wedging faces 54, 56 engaged with adjacent corner edges 58, 60 of the slab 24, thereby frictionally seizing the latter when the

members

50, 52 are squeezed toward each other while held in the hand. This construction, in addition to possessing the advantages of that shown in FIG. 5, permits a firmer seating of the slab 24 in the

members

50, 52 and results in an improved stiffness and rigidity of the erasing device.

FIG. 7 shows a modification of the invention wherein a one piece holder structure is employed. It comprises a single integral member 53, having a cross section substantially like the letter C, with a broadside constituting a connecting web 55 joining

channel sections

57, 59. Spaced

flanges

61, 62 and oppositely facing spaced edges 64, 66 serve to grip the erasing slabs in a fashion similar to that indicated by FIG. 5 and the description relating thereto.

The advantage of this construction is that it provides a more rigid body to support the erasing element than that of the type indicated in FIGS. 5 and 6. A second advantage lies in the fact that the holder in FIG. 7 is of single-piece construction, making for less handling and simpler assembly of components.

The provision of the clearance spaces between the erasing slab and the flanges of the holder in the vicinity of the connecting webs of the flanges is of considerable importance, in that it enables the holder to accommodate rubber slabs having wide dimensional variations in thickness. Thus, relatively thick slabs will not bind in the holder at the base portions of the spaced flanges (36, 38 of the member 32). Instead the flanges can yield in a manner that the space between them increases, to accommodate the thicker slabs. It is noted that the holding of exact dimensions is difiicult in the producing of slabs of rubberlike erasing material. Dimensional variations in width, of the erasing slabs, can be taken care of by allowing sufficient space where the one-piece holders are employed. Where two-piece holders are employed, of course, the holder can obviously accommodate slabs of greatly different widths.

Also, with the holder device of the present invention the user's grip on the holder forces the thin, free edges of the flanges 36, 38 (or 64, 66) to securely grip and slightly bite into the erasing slab. This effectively prevents slippage of the slab in the holder when the user is applying heavy erasing pressures. However, with the present yieldable and resilient holder construction there is had, in conjunction with such effective frictional seizing of the erasing slab, a surprisingly easy adjustment or advance of the slabs as they become worn. If the user grasps one end of the erasing device and with the other hand pulls or pushes the erasing slab at the other end, the slab will move quite easily due to the absence of applied force on the flanges at this other end. Such action, or course, applies to constructions involving two separate aligned slabs, since the adjustment of the one slab then does not require movement of the other slab which is being tightly held at the said one end of the erasing device.

It is further noted that the erasing slabs are normally flexible and resilient, and when the holder is constituted of two pieces or channel sections, the users grip on the holder will be accompanied by a slight transverse bending of the erasing slabs. The two holder pieces thus shift slightly out of their common plane which they normally occupy, and this results in edge comers of the holders tending to bite into the rubber slab, with a further tendency for the resilient holders to bindingly engage the slabs, all to the end that the slabs are effectively frictionally seized and held against slippage during the erasing procedure. The extremely simple, thin resilient holder members thus have a surprising action which is not at once apparent or obvious, both in gripping the slabs during use and in releasing the slabs for advance to compensate for wear. The plastic holder device, having rounded corners, in conjunction with the resilience of the erasing slabs, provides a surprisingly comfortable handle which does not indent the user's fingers in the manner of clamping metal sliders and the like.

It will now be seen from the foregoing that l have provided a novel and improved typists and draftmans erasing device presenting a narrow, elongate, firmly supported erasing edge especially suited for eradicating lines or letters sandwiched between othe. material. The erasing device can be either single ended or double ended, and in its simplest form comprises only two different components, i.e., a slab of erasing material and a semirigid channel-shaped holder piece. The grip applied to the holder by the user tends to cause the slabs to be more securely gripped. Due to the simplicity and few, simple parts, the cost of the components and the assembly is held to an absolute minimum. The slab is easily advanced as it becomes worn, and may be readily, economically replaced when completely used.

Variations and modifications are possible, and portions of the improvement may be used without others.

lclaim:

1. An eraser device comprising in combination:

a. a flat, elongate slab of rubberlike erasing material having a pair of broad parallel o posite faces, b. a substantially rigid hol er acketrng and frrctronally serzing said slab, said holder comprising a hollow structure constituted of thin resilient sheet material, said structure including a pair of oppositely facing, spaced channel sections each of which comprises a pair of spaced flanges and a connecting web, the outer surfaces of said webs comprising narrow longitudinal faces of said holder structure,

c. opposite longitudinal edge portions of said slab of erasing material occupying said channel sections in contact therewith and said slab being clamped between said spaced flanges,

. said holder structure when held between the fingers in the manner of a pencil for purposes of applying the slab of erasing material to a surface, yielding under the holding pressure so as to clamp the slab against slippage,

e. said holder structure comprising two separate substantially identical pieces, each piece constituting one of said channel sections,

. the channel sections adjacent the web portions thereof having wedging faces engaged with opposite edges of the slab, to frictionally seize the latter when the sections are squeezed toward each other while held in the hand.

Claims

1. An eraser device comprising in combination: a. a flat, elongate slab of rubberlike erasing material having a pair of broad parallel opposite faces, b. a substantially rigid holder jacketing and frictionally seizing said slab, said holder comprising a hollow structure constituted of thin resilient sheet material, said structure including a pair of oppositely facing, spaced channel sections each of which comprises a pair of spaced flanges and a connecting web, the outer surfaces of said webs comprising narrow longitudinal faces of said holder structure, c. opposite longitudinal edge portions of said slab of erasing material occupying said channel sections in contact therewith and said slab being clamped between said spaced flanges, d. said holder structure when held between the fingers in the manner of a pencil for purposes of applying the slab of erasing material to a surface, yielding under the holding pressure so as to clamp the slab against slippage, e. said holder structure comprising two separate substantially identical pieces, each piece constituting one of said channel sections, f. the channel sections adjacent the web portions thereof having wedging faces engaged with opposite edges of the slab, to frictionally seize the latter when the sections are squeezed toward each other while held in the hand.