US2895326A - Rug wear testing machine - Google Patents

Description

" July 21, 1959. J. FESPERMAN EIAL RUG WEAR TESTING MACHJINE Filed April l9, 1955 m w .nmm

pHy M r F m Lmm g m J m w United States Patent RUG WEAR TESTING MACHINE James L. Fesperman and 'Robert F. Hackney, Dalton, Gm, assignors to Cabin Crafts, Inc., Dalton, Ga., a corporation of Georgia Application April 19, 1955, Serial No. 502,386

Claims. (Cl. 73-7) This invention relates to wear testing machines and more particularly to machines for testing specimens or samples of rugs and like materials which are constantly subjected to wear by abrasion, friction and pressure such as by the feet of persons walking thereon.

It is an object of the invention to provide a testing machine of simple structure which may be economically assembled from component parts of simple form which may be inexpensively manufactured or bought on the market individually. A related object is to provide such a machine which will be durable and reliable in operation throughout a long life.

Another object of the invention is to provide a machine which will, as nearly as possible, duplicate the action of peoples feet on a rug in order to test the wearability of rug samples and like materials which are subjected to constant wear by people walking thereon.

Other objects and advantages of the invention will appear as it is described in connection with the accompanying drawing.

In the drawing:

a Fig. 1 is a side elevation view of a machine embodying the invention.

Fig. 2 is a plan view of the machine.

Fig. 3 is a detail view partly broken away of a portion of the machine.

Referring to the drawing, the machine may be mounted on a four legged or other suitable frame having a horizontal platform 10 on which is secured an electric motor 12 connected to reduction gearing 14 of standard form and construction which may be readily purchased on the market. A horizontal main drive shaft 16, rotating at reduced speed, extends from the gear box 14 and has flexibly mounted thereon for rotation therewith a sprocket 18. Around this sprocket 18 is trained a chain 19 which is also trained around a sprocket 20 on a horizontal intermediate shaft 22 parallel to and below the driving shaft 16. The intermediate shaft 22 is journaled in suitable bearings mounted on the platform 10. Besides the is in the form of a large disc but acts as a crank to drive a connecting rod 52, one end of which is pivotally connected therewith, while its opposite end is pivotally con nected with a shoe 54. The shoe 54 is preferably a rectangular block of metal but may have any desired shape suitable to press on the rug specimen and simulate the shoe of a person walking on the rug.

As illustrated, wearing action on the rug is applied by a fibre board plate or sole 55 on the bottom of the shoe 54. The shoe has a horizontal passage therethrough for a horizontal supporting rod 56 which is pivotally mounted at one end near the edge of the platform on a horizontal pin 58. The portion of the rod 56 near said pivotal mounting may be arched, if desired, to pass over the main shaft 16. The other end of the supporting rod 56 extends beyond the opposite end of the platform and is pivotally connected to the outer end of an upwardly extending piston rod 60 which projects from a pneumatic cylinder 62. The lower end of the cylinder has a longitudinal bearing member 63 extending therefrom, through which extends a horizontal pin 65 by which the cylinder is pivotally supported from the machine frame.

Within the cylinder 62 is a conventional piston, acted on by compressed air, as a D-type slide valve controlled by an electric solenoid is operated. The solenoid and valve are in a housing 64 secured against the end of the casing of cylinder 62, with which the valve passages comsprocket 20, the intermediate shaft also carries a pair of disc cams 24 and 25 and a second sprocket 26. All rotate with the shaft. Around the sprocket 26 is trained a chain 28 which drives another sprocket 30 affixed on shaft 32 below the platform 10 and parallel to the main drive shaft 16 and intermediate shaft 22.

Lower shaft 32 is mounted in bearings carried by platform 10, and carries another sprocket 34 around which is trained a horizontally running chain 36 which drives a sprocket 38 afiixed on a horizontal shaft 40 extending out of a reduction gear box 42 mounted beneath and supported from the platform 10 at the opposite end from motor12. l f

Extending up from the gear box 42 is a vertical shaft 44 which passes through the platform 10 and has mounted on its upper end a turntable 46 which rotates with the shaft 44. On the tablenthe specimen to be tested is removably fastened in any suitable fashion. The table turns very slowly by reason of the reduction gearing 42.

On the opposite end of the main shaft 16 from the sprocket 18 is a driving member 50 which, as illustrated,

municate. The valve admits compressed air from a source through a hose or pipe 61 at one side of the piston or the other, permitting exhaust from the cylinder in front or behind the piston as the piston is forced from one end of the cylinder to the other. An exhaust port is provided in the valve block for that purpose. Since the valve and the pneumatic piston and cylinder structures are purchased as a unit on the market and their functions are already known, their details are not shown. The valve solenoid is connected by wires 66', 66" from an electric cable 66 to a source of power and to electric switches 67, 68 of conventional construction. The switches are or may be of the momentary contact type and each is in series with the power source and with one or the other of the coils of the solenoid which move the air valve in its two opposite positions. The switches have arms 67, 68' extending therefrom in the path of the rotary cams 24 and 25 on the intermediate shaft 22. Lobes 24' and 25' on the cams are located 180 apart so that with each revolution of the cam, the switch it controls will be operated once. Switch 6'] causes the piston to descend and switch 68 causes the piston to ascend. The descent will cause the supporting rod 56 to rock downwardly and the shoe to press on the rug sample. Such action is timed to occur during the forward stroke of the shoe along the horizontal supporting rod 56. Raising of the shoe by ascent of the piston rod is timed to take place during the return stroke of the shoe along the supporting rod 56. Such timing is accomplished by having the cam shaft 22 rotate once for each rotation of the main shaft 16, such as by having the sprockets 18 and 20 equal. p,

In order to remove lint and dust as the rug sample wears and to tend to make the rug pile stand up, and also to hold the temperature normal by overcoming the heat generated by friction of the shoe on the sample, a narrow hollow hood 76 is attached to one side of the shoe and has extensions around the ends of the shoe. The hood is somewhat like the mouth of a vacuum cleaner and opens downwardly. The upper portion of the hood 3 the shoe is raised. By reason of the slow rotation of the table on which the sample is mounted, the wear is not directional but is applied at differing angles during the rotation of the table and sample. The sliding action of the shoe on the rug is similar to the action of a persons shoe upon a rug as he walks upon the rug. The pressure of the shoe upon the rug can be maintained constant throughout the test period or can be varied momentarily or over different periods by regulation of a pressure control valve 80 in the air supply line 82.

Preferably the shoe is made approximately the size of the sole of a mans shoe or approximately 4" by 5". Obviously, if desired, the shoe might be made of exactly the same form and configuration as a mans shoe with a sole and heel portion. Also, the shoe could be interchangeable and one shoe could be made the shape and configuration of a womans shoe, if it should be desired that the different conditions of wear to which rugs are normally subjected be more exactly reproduced by the machine. Under most conditions, however, it is believed that the shoe shape first described will suflice.

Due to the fact that some short period of time is necessary for the air to be exhausted from the cylinder beneath the piston, when compressed air is being caused to enter above the piston, the shoe will be pressed down after the start of, and during, the forward motion of the shoe and will engage the rug sample while the shoe is in forward motion. The exact point of engagement of the shoe relative to its position along the supporting rod can be regulated by adjustment of the cam 25 on the intermediate shaft. Similarly, the point at which the shoe is caused to rise from the sample relative to the position of the shoe along the supporting rod can be controlled by adjustment of the cam 24 on the intermediate shaft. In this way, if it is preferred to have the shoe start to rise from the rug at or just prior to the shoe reaching the end of its forward travel, the adjustment of the cam 24 can be made for that purpose. For counting the number of strokes made by the shoe, a counter 800 may be provided in position to have its actuating finger operated by the connecting rod 52 each time it descends.

From the foregoing, it may be readily understood that the invention provides means for closely simulating the action of peoples shoes upon a rug and enables measurements to be taken by laboratory instruments to determine the degree of wear, by measuring the thickness and weight of the rug sample at different stages of the test period. At all times the rug sample is maintained at normal temperature and heat. Many modifications within the scope of the invention will occur to those skilled in the art. Therefore, the invention is not limited to the exact form and arrangement of parts as illustrated and described in the embodiment disclosed.

What is claimed is:

1. A wear testing machine comprising a rotatable table upon which a test specimen is attachable, a movable shoe above the table, means to move the shoe to and fro over the specimen, means to press the shoe upon the specimen while the shoe moves in one direction, and to raise the shoe off the specimen and to move it in the other direction, and means to drive the shoe moving means and to rotate continuously the table in coordination therewith.

2. A wear testing machine as claimed in claim I having a pivoted supported member, said shoe being movable along and guided by said member.

3. A wear testing machine as claimed in claim 2 wherein the means to move the shoe to and fro comprises a crank and connecting rod arrangement causing more rapid motion of the shoe during the midportion of its movement over the specimen than at the ends of such movement.

4. A wear testing machine as claimed in claim 1 having crank and connecting rod means to move the shoe across the specimen, causing more rapid motion at the midportion of said movement than at the ends.

5. A wear testing machine as claimed in claim 1 having a suction head attached to the shoe, and means for connecting a suction hose to said head.

6. A Wear testing machine as claimed in claim 1 wherein the means to press and to raise the shoe comprises a pneumatic cylinder and piston, the piston being connected to said guide means.

7. A wear testing machine as claimed in claim 6 having electrically controlled valve means to control said cylinder and piston, and means operated by said drive to operate said valve means.

8. A Wear testing machine as claimed in claim 1 having crank and connecting rod means to move the shoe across the specimen, causing more rapid motion at the midportion of said movement than at the ends and wherein the means to press and to raise the shoe comprises a pneumatic cylinder and piston, the piston being connected to said guide means.

9. A Wear testing machine as claimed in claim 8 having electrically controlled valve means to control said cylinder 1 der and piston, and means operated by said drive to operate said valve means.

10. A wear testing machine as claimed in claim 1 having means attached to the shoe to draw 01f lint and dirt during operation of the machine and wherein the means to press and to raise the shoe comprises a pneumatic cylinder and piston, the piston being connected to said guide means.

11. A wear testing machine as claimed in claim 10 having electrically controlled valve means to control said cylinder and piston, and means operated by said drive to operate said 'valve means.

12. A wear testing machine comprising a rotary table on which a specimen to be tested may be attached, a shoe, a supporting member for said shoe along which the shoe is slidable, means to move said supporting member up and down and to press said shoe upon the specimen, means to slide said shoe along said supporting member, driving means causing said shoe to engage and press upon said specirnen'when moving inone direction only, and means coordinated with said driving means to rotate continuously said table to change the area of engagement of said shoe with said specimen.

13. A wear testing machine comprising a rotary table on which a specimen to be tested may be attached, a shoe, a supporting member for said shoe along which the shoe is slidable, pneumatically operated piston means pivotally connected to said supporting member to move it up and down and to press said shoe upon the specimen, means to slide said shoe alongsaid supporting member, driving means causing said shoe to engage and press upon said specimen when moving in one direction only, and means coordinated with said driving means to rotate said table to change the area of engagement of said shoe with said specimen.

14. A wear testing machine as claimed in claim 13 having electrically controlled valve means' to control said cylinder and piston, and means operated by said drive to operate said valve means.

15. A wear testing machine as claimed in claim 1 in which said shoe-raising means lifts the shoe off the specimen after the shoe starts to'move in said other direction.

References Cited in the file of this patent V UNITED STATES PATENTS 955,630 Carney et a1. Apr. 19, 1910 1,344,301 Jury l June 22, 1920 1,732,811 l-Iill p Oct. 22, 1929 1,906,175 Millet Apr. 25,1933 2,032,202 Dennis Feb. 25, 1936 2,100,332 Hathaway et al. Nov. 30, 1937 2,293,344 Kenyon et al. Aug. 18, 1942 2,412,221 Kallas et al. Dec/10, 1946 2,673,462 Thompson Mar. 30, 1954'

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