US3173231A

US3173231A - Sanding block

Info

Publication number: US3173231A
Application number: US221000A
Authority: US
Inventors: Nealy E Moyer
Original assignee: Individual
Current assignee: Individual
Priority date: 1962-09-04
Filing date: 1962-09-04
Publication date: 1965-03-16
Anticipated expiration: 1982-03-16

Description

N. E. MOYER SANDING BLOCK March 16, 1965 2 Sheets-Sheet 1 Filed Sept. 4, 1962 INVENTOR. 06541.) E. IMO/ER ATTOR/YEKF N. E. MOYER SANDING BLOCK March 1 1965 2 Sheets-Sheet 2 Filed Sept. 4, 1962 INVENTOR. WEAL) 5. MOYE/P ATTOPIYEYS United States Patent 3,173,231 SANDING BLOCK N ealy E. Meyer, Rte. 2, Blue Springs, Me. Filed Sept. 4, 1962, Ser. No. 221,000 4 Claims. (Cl. 51-391) This invention relates to abrading tools, and more particularly to improvements in hand-held sanding blocks.

In many applications, and particularly with regard to the repair of modern automobile bodies, elongated concave grooves must be abraded for removing unwanted filling material and smoothing prior to finishing. Such grooves are formed on many difierent radii and heretofore a great number of different sanding tools were required in order to permit the selection of one which presented a matching convex surface for accurate forming. Various attempts have been made to avoid the bother and expense of stocking a great number of abrading tools by using resilient cores or resilient material layers beneath abrading sheet material for bulging same into the desired curvature. Such attempts have generally not been satisfactory because variations in pressure against the abrading tool produced variations in the curvature of the cutting surface, rendering it very difiicult to produce an accurate smooth groove suitable for finishing. Attempts have also been made to produce rigid core abrading tools having curved surfaces over which abrasive sheets may be stretched; however, such devices often presented difi'iculties in sheet mounting and failed to maintain the abrasive sheet in a sufiiciently tightly stretched condition over a length required for accurate work.

The principal objects of the present invention are: to provide an abrading device which presents an elongated rigid cutting surface having a transverse cross-sectional contour of constantly changing convex curvature for ease in fitting into elongated concave grooves of various radii; to provide the combination of an elongated abrasive sleeve and a sleeve supporting core which cooperate with each other in producing an elongated rigid abrading tool; to provide a simple abrading device wherein a sleeve having abrasive material on the outside surface thereof acts to prevent axial bending between segmented portions of a core which forms and supports the sleeve in a desired peripheral contour; to provide such a device wherein the core is snugly slidably received in the sleeve and, without further adjustment being required, transversely deforms the sleeve into a shape conforming to the outside surface of the core; to provide such a device which may be used in lengthened or shortened form depending upon the tool length desired; and to provide such a combination wherein adjustable parts for clamping or unclamping the abrasive material are not required.

Other objects and advantages of this invention will become apparent from the following description taken in connection with the accompanying drawings wherein are set forth by way of illustration and example certain embodiments of this invention.

FIG. 1 is a perspective view of an assembled abrading tool embodying this invention with a part broken away to show connected core portions.

FIG. 2 is a fragmentary perspective view on a reduced scale showing the use of the abrading tool of FIG. 1 on an automobile body groove.

FIG. 3 is a fragmentary cross-sectional view through the tool and automobile body of FIG. 2 showing a portion of the abrading surface in curving contact with the automobile body groove.

FIG. 4 is an exploded view showing two elongated axially separable segmented portions of an abrasive sleeve supporting core embodying this invention.

FIG. 5 is a perspective view showing an elongated abrasive sleeve in commercially available cylindrical form.

FIG. 6 is a fragmentary cross-sectional view on an enlarged scale taken longitudinally through one end of the core particularly illustrating a finger receiving grasping socket for withdrawing a core portion from the abrasive sleeve.

FIG. 7 is a fragmentary perspective view illustrating aligning and joining members on the core portions.

Referring to the drawings in more detail:

The reference numeral 1 generally indicates an abrading tool or sanding block embodying this invention. The tool 1 includes an elongated abrasive sleeve 2 and a sleeve supporting core 3. The sleeve 2, prior to assembly with the core 3, is normally in the form of an elongated cylinder (FIG. 5) which is commercially available in many desired lengths and grits and, if desired, may be easily cut to shorter lengths. The sleeve 2 is substantially smooth on the inside surface 4 thereof. In the illustrated example said inside surface 4 is composed of a biased cut fabric impregnated or coated with a suitable synthetic resin so that it will firmly adhere to a paper cylinder 5 which carries an abrasive material or grit 6 on the outside surface 7 thereof. The sleeve 2 is of the common type which is relatively easily deformable in transverse cross-sectional profile but strong or substantially rigid against axial bendmg.

The core 3, in the illustrated example, is composed of two elongated straight rigid axially separable segmented portions respectively designated 8 and 9, which are preferably of different lengths for a purpose described hereinafter. A greater number of core portions may be used without departing from the spirit of this invention. The portion 9 has a suitable square-shaped depression 10 in the end thereof facing the portion 3 and the portion 8 has a square-shaped projection 11 adapted to be received in the depression 10 for aligning and axially joining the

portions

8 and 9 together. It is to be understood that the clearances between the depression 10 and projection 11 are such that the

portions

8 and 9 are generally main tained in a coaxial relationship; however, if small transverse forces are applied, the

portions

8 and 9 will separate slightly forming an angle with each other at the plane 12 of juncture.

The core 3 (when the portions 8 and 0 are joined to gether) has a length substantially equal to the length of the sleeve 2. The core 3 is formed of any suitable material such as aluminum or wood and has a constant transverse cross-sectional peripheral contour 13 along the entire length thereof. The peripheral contour 13 of the core 3 has a continuous constantly changing convex curvature terminating at outwardly oppositely facing ends 14 and 15 thereof in apices of respectively different curvatures. The constantly changing convex curvatures as they extend away from the ends 14 and 15 are believed to be best characterized as sections of parabolas. The peripheral contour 13 of the core 3 has a circumference substantially equal to or slightly less than the circumference of the sleeve inside surface 4 whereby the core 3 may be snugly slidably received in the sleeve 2. It has been found that .040 or .050 inch diiference on a three inch circumference permits adequate sliding therebetween. When inserted in the sleeve, the core 2 transversely deforms the sleeve whereupon the abrasive surface 7 conforms to the core peripheral contour 13.

Since the sleeve 2 is substantially rigid in axial bending characteristics, the combination of sleeve and core presents a device which is axially rigid, although the

portions

8 and 9 of the core without the sleeve would admit to axial bending with respect to each other. Thus the sleeve and core form an elongated abrading tool presenting a rigid advantageously curved abrading surface.

In operation, the abrading tool 1 is held in the hands and urged against the automobile body 16. The tool 1 is rotated along the longitudinal axis thereof until the proper curvature is received in and contacts the desired concave area 17 of the body'groove 17'. As much pressure as desired may then be placed on the tool 1 in the direction of the groove center, and the tool is reciprocated longitudinally of the groove until proper smoothing and blending is obtained. The application or release of pressure against the tool 1 will not result in a changing of the abrading surface curvature since there is rigid support therebeneath. Since the length of the sleeve 2 and core 3 are substantially equal, nothing extends outwardly of the ends of the tool 1 to interfere with the operation thereof in places having limited working space.

It is desirable to have grasping means to facilitate removing the core from the sleeve, for example, to exchange the sleeve for one of different grit. In the illustrated example, such grasping means comprises a sloping depression or passageway 18 entering into the body of the core 3 at the outside ends 19. The passageway 18 is of sufficient size to permit the entry of a finger 20 thereinto and a suitable cross pin 21 extends through the body of the sleeve 2 permitting the finger 20 to engage therewith in applying an axial withdrawal force on the core 3 with respect to the sleeve 2. It is noted that the cooperating guiding member (depression and projection 11) easily separate axially of the tool 1 and the

respective portions

8 and 9 may be withdrawn from opposite ends of the sleeve 2 with much greater ease than a single elongated core since friction between the sleeve and core acting against withdrawal operates only on the shorter individual core portions.

It has been found that a convenient length for the tool 1 is 20 inches with the

individual core portions

8 and 9 being 6 inches and 14 inches in length respectively. If a short length abrading tool is desired, either of the

portions

8 or 9 may be used individually by severing a length of the sleeve 2 to the proper dimension.

The above-described abrading tool is highly convenient for not only removing filler to the proper depth and contour for painting within a groove, but the groove curves may be blended into other surfaces easily and without the great skill heretofore necessary for such operation. It is to be understood that although one form of this invention has been illustrated and described, it is not to be limited to the specific form or arrangement of parts herein 7 described and shown except insofar as such limitations are included in the claims.

What I claim and desire to secure by Letters Patent is: 1. In combination, an elongated abrasive sleeve and an elongated and sleeve supporting core:

said core being of rigid material and unitary in crosssection transverse to the length thereof and of constant transverse cross-sectional peripheral contour along the length thereof,

(c) said core peripheral contour having a circumference substantially equal to the circumference of said sleeve inside surface, said core peripheral contour having a continuous constantly changing convex curvature terminating at outwardly oppositely facing ends thereof in apices of respectively different curvature,

(:1) said core being snugly slidably received in said sleeve and transversely deforming said sleeve whereupon said outside surface thereof conforms to said core peripheral contour, whereby an elongated rigid concave groove abrading tool is formed.

2. The combination of claim 1 including:

(a) finger-engaging means on end of said core for slidably removing said core from said sleeve.

3. In combination, an elongated abrasive sleeve and an elongated sleeve supporting core:

(a) said sleeve normally being cylindrical in form and substantially smooth on the inside surface thereof and having abrasive material on the outside surface thereof, said sleeve being easily deformable in transverse cross-sectional profile but substantially rigid in axial bending,

(b) said supporting core being composed of at least two elongated straight segmented portions axially separable along the longitudinal axis of said core, cooperating guide means on said portions for axially joining same but permitting axial bending therebetween, said core having a length substantially equal to the length of said sleeve, said core being of rigid material and unitary in cross-section transverse to said axis and of constant transverse cross-sectional peripheral contour along the length thereof,

(0) said core peripheral contour having a continuous constantly changing convex curvature and having a circumference substantially equal to the circumference of said sleeve inside surface,

(0.) said core being snugly slidably received in said sleeve and transversely deforming said sleeve whereupon said outside surface thereof conforms to said core peripheral contour,

(2) said sleeve maintaining said core portions in coaxial relation whereby an elongated rigid concave groove abrading tool is formed.

4. The combination of claim 3 including:

(a) finger-engaging means on outer ends of said core for slidably removing said portions from said sleeve.

References Cited by the Examiner UNITED STATES PATENTS 3/42 Johnson 51-185 1/50 Bonkowski 51-187 11/50 Stucker 51l87 @WW. have

Claims

1. IN COMBINATION, AN ELONGATED ABRASIVE SLEEVE AND AN ELONGATED AND SLEEVE SUPPORTING CORE: (A) SAID SLEEVE NORMALLY BEING CYLINDRICAL IN FORM AND SUBSTANTIALLY SMOOTH ON THE INSIDE SURFACE THEREOF AND HAVING ABRASIVE MATERIAL ON THE OUTSIDE SURFACE THEREOF, SAID SLEEVE BEING EASILY DEFORMABLE IN TRANSVERSE CROSS-SECTIONAL PROFILE BUT SUBSTANTIALLY RIGID IN AXIAL BENDING. (B) SAID SUPPORTING CORE BEING STRAIGHT AND HAVING A LENGTH SUBSTANTIALLY EQUAL TO THE LENGTH OF SAID SLEEVE, SAID CORE BEING OF RIGID MATERIAL AND UNITARY IN CROSSSECTION TRANSVERSE TO THE LENGTH THEREOF AND OF CONSTANT TRANSVERSE CROSS-SECTIONAL PERIPHERAL CONTOUR ALONG THE LENGTH THEREOF, (C) SAID CORE PERIPHERAL CONTOUR HAVING A CIRCUMFERENCE SUBSTANTIALLY EQUAL TO THE CIRCUMFERENCE OF SAID SLEEVE