US2822686A - Wear and abrasion testing machine - Google Patents

Wear and abrasion testing machine Download PDF

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US2822686A
US2822686A US483263A US48326355A US2822686A US 2822686 A US2822686 A US 2822686A US 483263 A US483263 A US 483263A US 48326355 A US48326355 A US 48326355A US 2822686 A US2822686 A US 2822686A
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jig
abrasive
plated
wear
test piece
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US483263A
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Campana Charles Ralph
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    • GPHYSICS
    • G01MEASURING; TESTING
    • G01NINVESTIGATING OR ANALYSING MATERIALS BY DETERMINING THEIR CHEMICAL OR PHYSICAL PROPERTIES
    • G01N3/00Investigating strength properties of solid materials by application of mechanical stress
    • G01N3/56Investigating resistance to wear or abrasion

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  • the present invention relates to a wear and abrasion testing machine, and more particularlyto a machine for testing the wear resistance of gold plated articles.
  • -Wear resistance is dependent upon the composition and the thickness of the gold plate since certain plate coating compositions containing less gold but greater thickness have a longer useful life than other compositions containing more gold and less thickness.
  • the hardness of the plated coating also constitutes an important factorin the wearability of the article. Hence, without knowledge in advance of the probable useful life of the plated surface, a manufacturer cannot be certain that his product reputation may not be impaired.
  • a further object of the invention is to provide a machine of the character set forth wherewith comparative tests may be made, either simultaneously or at different times, of the surfaces of articles plated under different conditions or with different plating compositions, by one plating establishment or by a competitor.
  • 'A still further object of the invention is to provide a machine of the character set forth, adapted to removably accommodate jigsforsupporting difierenttypes of plated articles to be tested.
  • a still further object of the invention is to provide amachine of the character set forth wherein the probability of error is reducedrto a I 'Yet a further object of the invention is to provide a machine of the character set forth wherewith it can be quicklyv determined whether the thickness of the plated coating should be increased or decreased to meet certain specifications.
  • Y 'L The foregoing and other objects of the invention not specifically enumerated, I accomplish by providing a ma chine wherein, by repeatedly moving the plated article to be tested and an abrasive carrying material relatively to each other, a predetermined number of times, under controlled conditions of speed of movement, coeflicient of friction and character of abrasive used, comparisons 2,822,686 Patented F eh.
  • Figure 1 is a top plan view of the machine embodying the invention, the frame for supporting the abrasive carrying elements being omitted.
  • Fig. 2 is a longitudinal sectional view taken along the broken line 22 of Fig. 1, showing the frame with the abrasive carrying elements in raised or inoperative position.
  • Fig. 3 is a transverse view taken along the line 3--3 of Fig. 2 and showing the abrasive carrying elements in operative position. 1
  • Fig. 4 is a top plan view of the frame for the abrasive carrying element.
  • Fig. 5 is a sectional view taken on the line 5-5 of Fig. 1.
  • Fig. 6 is a detailed side elevational view of the relationship of an abrasive element as shown in Figs. 2 and 3, in operative neutral testing position on a test piece.
  • Fig. 7 is a view similar to Fig. 6 showing the abrasive element in the position that it will occupy when the jig support has been moved to its left limiting position.
  • Fig. 8 is a fractional sectional side view similar to Fig. 6, of a modified form of the invention.
  • the abrasion testing machine consists essentially of a bed 10, a' reciprocating jig support 11, an abrasive element supporting frame 12,'an odometer 13, an electric motor 14, a timer 15, a light source 16 and a light diffuser 17.
  • a base plate 18 mounted on the bed 10 is a base plate 18, at one end of which is supported the odometer 13, which is connected through a pitman 19 to the reciprocable jig support 11 to record the number of reciprocations of of said jig support.
  • a plurality of crossties 20'to' which are secured a pair of parallelly disposed angle members 21, which, in turn, support a plurality of anti-friction rollers 22 over which the jig support is reciprocated.
  • a plurality of upstanding bolts 23 adapted to adjustably support, in spaced relation to thereciprocable jig support .11, a stationary frame member 24 which carries a secondary frame member 25, to one end of which is pivotally connected by hinges 26 the abrasive element supporting frame 12.
  • Vertical adjustment of the frame 24 is accomplished through adjusting nuts 27 and 28 on the bolts 23.
  • the motor 14 which, through a reducing gear box 29, rotates a disc 30 to which is eccentricallyand pivotally connected one end of a pitman 31, the other end of which is pivotally connected to an extension, member 31a mounted on the jig support 11,. It is through the.
  • the jig support 11 which is in the form of a plate, is adapted to have removably mounted thereon various types of jigs, adapted to hold test pieces, two such types being shown.
  • One of said jigs 32 is adapted to hold clips for fountain pens, pencils and the like, and another two-part jig 33a, 33b is adapted to hold barrels for pens, pencils and the like.
  • the jig 32 is formed with a longitudinal slot 34 (Figs.
  • the part 33a of the two-part jig (Fig. 5) carries a plurality of adjustable barrel supports 40, while the part 33b carries a plurality of spring-pressed barrel tip supports which are urged outwardly from the support by coilsprings 42.
  • the barrel; mernhers 43 will be spring-held within the two:part jigs33a and 33b and can be readily removed therefrom by moving the barreltip support 21 rearwardlyagainst the force of the spring 42;
  • the jigs 32, and 33a, 3312 may be of any desired construction; depending upon the shape of the test piece which it is intended to hold.
  • the abrasive element-supporting frame 12 as shown in Figs. 2, 3, 4, 6 and 7 consists of a rectangular plate having a plurality of aligned, spaced, rectangular sockets 44 each of which is adapted to have mounted therein an abrasive carrier 45, which, when mounted in a socket, will overlie a test piece in a jig to be floatingly supported by the test piece.
  • the abrasive carrier consists of a head 45 and a substantially semi-cylindrical body 47 having secured to its peripheral surface a deformable elastic cushioning strip 48 and an abrasive element 49 which is softer than the test piece.
  • abrasive element is clamped between the head and thebody by a screw 50.
  • the headand ;body are formed of a heavy metal, the weight of which will, of course, be applied to the abrasive strip to produce a desired coefficient of friction between the abrasive element and the test piece.
  • the screw 59 may be made longer than is necessary and may'have split washers 51 mounted thereon.
  • the sockets 44 are of somewhat larger dimension than the diameter of the body members 47 so as to permit a slight rocking movement of the abrasive element over the test piece as the test piece is reciprocated in frictional contact with the abrasive element.
  • the supporting frame 12 and the secondary frame member 25 may be connected together by toggles 52 and the supporting frame with a lifting bail 52a.
  • the motor 14 is adapted to receive its electrical energy from any source,- herein shown as an outlet box 53 having a control switch 54.1
  • the motor is connected to the timer 15 which, knowing the speed of the motor, the number of reciprocations, of the support jig may be controlled by a dial 55.
  • a visible indicating means such as an electric light bulb 5 6
  • an audible signaling means such as a buzzer (not shown).
  • the outlet box 53 and the timer 15 maybe mounted at any de- 4 sired location but, in order that the testing machine be constituted as a single unit, said parts are modified on the light difiuser plate 17, which is herein shown as supported on the bed 10 by a pair of angle brackets 57.
  • the light source 17 herein shown as a fluorescent tube 16 is also preferably mounted to the rear of the light difiuser plate 17 so asto provide a diffused light under which test pieces may be examined during or at the completion of a test.
  • abrasive element-supporting frame 12 is formed with a rigid tubular member 58 within the care of which is floatingly mounted an abrasive carrier 59 in the form of a metal tube, within which is mounted a pencil-like abrasivecontaining member 60 having a core 61 formed of deformable elastic material such as the conventional rubber eraser material used in typewriter erasers ofthe pencil type. If desired, the pencil-like member tiff may be fixedly secured to the carrier 59 by a set-screw 62.
  • a machine for testing the wear resistance ofga; plated article comprising a base member, a jig for holding a plated test piece, said jig being movably supported on the base member, a stationary frame membersup ported on the base member and having a socket therein" overlying the jig, an abrasive element and a carrier therefor floatingly disposed in the socket in the-frame; said abrasive element being elastically deformable and softer than the plated test piece with which it is toco: operate and under the weight of the carrier being adaptedto bear upon such test piece when mountedqin the jig, and means for reciprocating the jig so that the abrasive element will rub over the plated surface of the test piece when mounted in the jig;
  • a machine according to claim 1 wherein the carrier for the abrasive element is a floating plunger vertically movable in the socket in the frame member and the abrasive element is of deformable elastic material-.-
  • the plunger is a pencil-like member having a core of rubber erasure material which extends through the lower end of the plunger.

Description

Feb. 11, 1958 c. R. CAMPANA WEAR AND ABRASION TESTING MACHINE Filed Jan. 21, 1955 2 Sheets-Sheet 1 IN VEN TOR LLL Charles R. Campana BY HTTORN Y6.
W A7 22 1 22 11 ft Feb. 11, 1958 c, R. CAMPANA 2,822,686
WEAR AND ABRASION TESTING MACHINE Filed Jan. 21, 1955 2 Sheets-Sheet 2 x Tl INVENTOR.
Clzarles R. Cam Jana armgmz'm United States Patent O ce WEAR AND ABRASION TESTING MACHINE Charles Ralph Campana, New York, N. Y.
: Application January 21, 1955, Serial No. 483,263
' 4 Claims. c1. 13-1 The present invention relates to a wear and abrasion testing machine, and more particularlyto a machine for testing the wear resistance of gold plated articles.
In the mass production of gold plated articles of commerce such as ball point and fountain pen parts, mechanical pencil parts, items of jewelry, etc., the demand of the trade is such that the manufacturer must know the probable life or duration of the gold plated surface when the articles are subjected to ordinary wear. The commercial plating establishments must also know,
for competitive reasons, the wear resistance of plated surfaces which will satisfy manufacturer's demand. v
-Wear resistance is dependent upon the composition and the thickness of the gold plate since certain plate coating compositions containing less gold but greater thickness have a longer useful life than other compositions containing more gold and less thickness. The hardness of the plated coating also constitutes an important factorin the wearability of the article. Hence, without knowledge in advance of the probable useful life of the plated surface, a manufacturer cannot be certain that his product reputation may not be impaired.
' Prior to the present invention, so far as I am aware, no simple and accurate means were available for determining the wear resistance of a plated article or for making comparisons of the wear resistance of plated articles originating from the same or diiferent plating establishments.
Accordingly, it is a primary object of the present invention to provide a testing machine wherewith various types of plated articles, and particularly gold plated arti- 'cle's, can be quickly and accurately tested for wear resistance.
A further object of the invention is to provide a machine of the character set forth wherewith comparative tests may be made, either simultaneously or at different times, of the surfaces of articles plated under different conditions or with different plating compositions, by one plating establishment or by a competitor. 'A still further object of the invention is to provide a machine of the character set forth, adapted to removably accommodate jigsforsupporting difierenttypes of plated articles to be tested.
A still further object of the invention is to provide amachine of the character set forth wherein the probability of error is reducedrto a I 'Yet a further object of the invention is to provide a machine of the character set forth wherewith it can be quicklyv determined whether the thickness of the plated coating should be increased or decreased to meet certain specifications. Y 'L The foregoing and other objects of the invention not specifically enumerated, I accomplish by providing a ma chine wherein, by repeatedly moving the plated article to be tested and an abrasive carrying material relatively to each other, a predetermined number of times, under controlled conditions of speed of movement, coeflicient of friction and character of abrasive used, comparisons 2,822,686 Patented F eh. 11, 1958 can be made of the plated surfaces to be tested with plated articles having known properties of abrasion resistance. Preferably, in the operation of the machine the abrasive carrying element is floatingly supported on the article to be tested and is loaded with a predetermined force which may be varied as desired, or standardized. The invention, the machine embodying the same and its operation will be readily understood from a consideration of the detailed description which follows, when considered in connection with the accompanying drawings, wherein:
Figure 1 is a top plan view of the machine embodying the invention, the frame for supporting the abrasive carrying elements being omitted.
Fig. 2 is a longitudinal sectional view taken along the broken line 22 of Fig. 1, showing the frame with the abrasive carrying elements in raised or inoperative position.
Fig. 3 is a transverse view taken along the line 3--3 of Fig. 2 and showing the abrasive carrying elements in operative position. 1
Fig. 4 is a top plan view of the frame for the abrasive carrying element.
Fig. 5 is a sectional view taken on the line 5-5 of Fig. 1.
Fig. 6 is a detailed side elevational view of the relationship of an abrasive element as shown in Figs. 2 and 3, in operative neutral testing position on a test piece.
Fig. 7 is a view similar to Fig. 6 showing the abrasive element in the position that it will occupy when the jig support has been moved to its left limiting position.
Fig. 8 is a fractional sectional side view similar to Fig. 6, of a modified form of the invention.
Referring first to Figs. 1 to 7 of the drawings, the abrasion testing machine consists essentially of a bed 10, a' reciprocating jig support 11, an abrasive element supporting frame 12,'an odometer 13, an electric motor 14, a timer 15, a light source 16 and a light diffuser 17.
Mounted on the bed 10 is a base plate 18, at one end of which is supported the odometer 13, which is connected through a pitman 19 to the reciprocable jig support 11 to record the number of reciprocations of of said jig support. Also mounted on the base plate 18 are a plurality of crossties 20'to' which are secured a pair of parallelly disposed angle members 21, which, in turn, support a plurality of anti-friction rollers 22 over which the jig support is reciprocated. Also mounted on the angle members 21 are a plurality of upstanding bolts 23 adapted to adjustably support, in spaced relation to thereciprocable jig support .11, a stationary frame member 24 which carries a secondary frame member 25, to one end of which is pivotally connected by hinges 26 the abrasive element supporting frame 12. Vertical adjustment of the frame 24 is accomplished through adjusting nuts 27 and 28 on the bolts 23. Also mounted on the bed 10 is the motor 14 which, through a reducing gear box 29, rotates a disc 30 to which is eccentricallyand pivotally connected one end of a pitman 31, the other end of which is pivotally connected to an extension, member 31a mounted on the jig support 11,. It is through the. motor 14, reducing gear box 29, disc 30 and pitman 31 that the jig support is reciprocatedi The jig support 11, which is in the form of a plate, is adapted to have removably mounted thereon various types of jigs, adapted to hold test pieces, two such types being shown. One of said jigs 32 is adapted to hold clips for fountain pens, pencils and the like, and another two- part jig 33a, 33b is adapted to hold barrels for pens, pencils and the like. The jig 32 is formed with a longitudinal slot 34 (Figs. 6 and 7) and with a plurality of transverse grooves 35 and \vitlrt1'ansverse holes 36 extending from one end of the jig into the slot 34 and adapted to accommodate plugs 37 for frictionally holding the bent end 38 f a clip 39 within the grooves 35. Only one such clip 39 andplug 37 is shown as mounted in the jig 32 ori Fig. 1 ,-;although it will be apparent from an inspection ofsaid figure that the jig is adapted to accommodate five such clips". The part 33a of the two-part jig (Fig. 5) carries a plurality of adjustable barrel supports 40, while the part 33b carries a plurality of spring-pressed barrel tip supports which are urged outwardly from the support by coilsprings 42. It will thus be seen that the barrel; mernhers 43 will be spring-held within the two:part jigs33a and 33b and can be readily removed therefrom by moving the barreltip support 21 rearwardlyagainst the force of the spring 42; Obviously, the jigs 32, and 33a, 3312 may be of any desired construction; depending upon the shape of the test piece which it is intended to hold.
The abrasive element-supporting frame 12 as shown in Figs. 2, 3, 4, 6 and 7 consists of a rectangular plate having a plurality of aligned, spaced, rectangular sockets 44 each of which is adapted to have mounted therein an abrasive carrier 45, which, when mounted in a socket, will overlie a test piece in a jig to be floatingly supported by the test piece. The abrasive carrier consists of a head 45 and a substantially semi-cylindrical body 47 having secured to its peripheral surface a deformable elastic cushioning strip 48 and an abrasive element 49 which is softer than the test piece. The
abrasive element is clamped between the head and thebody by a screw 50. Preferably the headand ;body are formed of a heavy metal, the weight of which will, of course, be applied to the abrasive strip to produce a desired coefficient of friction between the abrasive element and the test piece. If it is desired to vary the force or total weight of the abrasive carrier, the screw 59 may be made longer than is necessary and may'have split washers 51 mounted thereon. Preferably the sockets 44 are of somewhat larger dimension than the diameter of the body members 47 so as to permit a slight rocking movement of the abrasive element over the test piece as the test piece is reciprocated in frictional contact with the abrasive element. In Fig. 7 there is shown the relationship of the abrasive carrier to the test piece at the forward end of the stroke of the reciprocable jig support 11'. To hold the abrasive element supporting frame 12 in inoperative position so as to permit inspection of the test piece after it has been subjected to a predetermined number of reciprocations in contact with the abrasive element, the supporting frame 12 and the secondary frame member 25 may be connected together by toggles 52 and the supporting frame with a lifting bail 52a.
The motor 14, as will be apparent, is adapted to receive its electrical energy from any source,- herein shown as an outlet box 53 having a control switch 54.1 The motor is connected to the timer 15 which, knowing the speed of the motor, the number of reciprocations, of the support jig may be controlled by a dial 55. To apprise an operator in carrying out a test that the predetermined reciprocations have been completed, there is associated with the timer a visible indicating means such as an electric light bulb 5 6, and if desired, there may be also associated with the timer an audible signaling means such as a buzzer (not shown). The outlet box 53 and the timer 15 maybe mounted at any de- 4 sired location but, in order that the testing machine be constituted as a single unit, said parts are modified on the light difiuser plate 17, which is herein shown as supported on the bed 10 by a pair of angle brackets 57.
The light source 17 herein shown as a fluorescent tube 16 is also preferably mounted to the rear of the light difiuser plate 17 so asto provide a diffused light under which test pieces may be examined during or at the completion of a test. Q
In Fig. 8 of the drawings I have shown a modified form of abrasive carrier which ma be used for certain types of tests. As shown in said figure, the abrasive element-supporting frame 12 is formed with a rigid tubular member 58 within the care of which is floatingly mounted an abrasive carrier 59 in the form of a metal tube, within which is mounted a pencil-like abrasivecontaining member 60 having a core 61 formed of deformable elastic material such as the conventional rubber eraser material used in typewriter erasers ofthe pencil type. If desired, the pencil-like member tiff may be fixedly secured to the carrier 59 by a set-screw 62.
With a testing machine ashereinbefore described and illustrated in the drawings, it will be apparent--that the hardness or wear resistance of a plated coatingsuch as a gold plate on a basemetalpart may be quickly, ac-' curately and economically determined, and while I have shown certain preferred embodiments of the invention,- it willbe understood that changes in constructional de-1 tails thereof may be resorted to within the range of engineeringand mechanical skill without departing from thespiritof the invention as claimed.
What I claim is:
1. A machine for testing the wear resistance ofga; plated article, comprising a base member, a jig for holding a plated test piece, said jig being movably supported on the base member, a stationary frame membersup ported on the base member and having a socket therein" overlying the jig, an abrasive element and a carrier therefor floatingly disposed in the socket in the-frame; said abrasive element being elastically deformable and softer than the plated test piece with which it is toco: operate and under the weight of the carrier being adaptedto bear upon such test piece when mountedqin the jig, and means for reciprocating the jig so that the abrasive element will rub over the plated surface of the test piece when mounted in the jig;
2. A- machine according to claim 1 wherein the abrasive element and the carrier therefor as a unit has a convex surface for contacting'the test piece so'as to be rockable by the test piece as the jig is reciprocated.
3. A machine according to claim 1 wherein the carrier for the abrasive element is a floating plunger vertically movable in the socket in the frame member and the abrasive element is of deformable elastic material-.-
4. A machine according to claim 3, wherein the plunger is a pencil-like member having a core of rubber erasure material which extends through the lower end of the plunger.
References Cited in the file of this patent UNITED STATES PATENTS
US483263A 1955-01-21 1955-01-21 Wear and abrasion testing machine Expired - Lifetime US2822686A (en)

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Cited By (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US2969669A (en) * 1955-05-10 1961-01-31 Ronson Metals Corp Abrasion testing apparatus
US3688556A (en) * 1971-06-25 1972-09-05 Us Army Wear testing apparatus
US3834219A (en) * 1972-08-22 1974-09-10 Olin Corp Process and apparatus for predicting the tool wear characteristics of metal sheet

Citations (7)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US1108928A (en) * 1907-11-08 1914-09-01 William E Nickerson Apparatus for testing the durability of cutting edges.
US1478335A (en) * 1919-02-01 1923-12-18 Norton Co Method of and apparatus for grading
US1483662A (en) * 1922-09-25 1924-02-12 Mitchell F Jamar Testing and display device
US2032202A (en) * 1934-12-27 1936-02-25 Calvin L Dennis Testing machine
US2079591A (en) * 1935-03-15 1937-05-11 Floyd E Bartell Textile testing machine
US2660055A (en) * 1947-04-08 1953-11-24 Geigy Ag J R Apparatus for testing the fastness of dyeings on wetted textiles
US2721473A (en) * 1951-02-05 1955-10-25 Custom Scient Instr Inc Fabric testing machine

Patent Citations (7)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US1108928A (en) * 1907-11-08 1914-09-01 William E Nickerson Apparatus for testing the durability of cutting edges.
US1478335A (en) * 1919-02-01 1923-12-18 Norton Co Method of and apparatus for grading
US1483662A (en) * 1922-09-25 1924-02-12 Mitchell F Jamar Testing and display device
US2032202A (en) * 1934-12-27 1936-02-25 Calvin L Dennis Testing machine
US2079591A (en) * 1935-03-15 1937-05-11 Floyd E Bartell Textile testing machine
US2660055A (en) * 1947-04-08 1953-11-24 Geigy Ag J R Apparatus for testing the fastness of dyeings on wetted textiles
US2721473A (en) * 1951-02-05 1955-10-25 Custom Scient Instr Inc Fabric testing machine

Cited By (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US2969669A (en) * 1955-05-10 1961-01-31 Ronson Metals Corp Abrasion testing apparatus
US3688556A (en) * 1971-06-25 1972-09-05 Us Army Wear testing apparatus
US3834219A (en) * 1972-08-22 1974-09-10 Olin Corp Process and apparatus for predicting the tool wear characteristics of metal sheet

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