US3580621A

US3580621A - Eyelet and lug assembly

Info

Publication number: US3580621A
Application number: US3619*[A
Authority: US
Inventors: Robert F Chambers
Original assignee: Individual
Current assignee: Individual
Priority date: 1970-03-23
Filing date: 1970-03-23
Publication date: 1971-05-25
Anticipated expiration: 1988-05-25

Abstract

Assembly comprises eyelet in form of shaft with series of lugs mounted on shaft. Each lug includes looped end portion of same thickness that loosely surrounds shaft and coplanar end portion of same thickness as looped portion. Looped portions of lugs contact one another in line on shaft. At least one of end lugs in line includes additional portion connected and equal in thickness to its coplanar end portion with additional portion offset in direction of adjacent lug in line.

Description

United States Patent Inventor Robert F. Chambers 504 Beverly Road. Newark, Del. 19711 Appl No 003,619 Filed Mar. 23. 1970 Division of Ser. .\'o. 735.259. June 7. 1968. Pat. No. 3,520,981. Patented May 25, 1971 EYELET AND LUG ASSEMBLY 2 Claims, 3 Drawing Figs.

US. Cl. 287/101, 35/ l 9 Int. Cl F16c 11/00 Field of Search 287/101; 35/34, 19

[56] References Cited UNITED STATES PATENTS 1,975,685 10/1934 Eglinton 287/101X 2,307,657 1/1943 Anderson 287/91 2,546,043 3/1951 Pannenter v. 287/101X Primary Examiner-David J Williamowsky Assistant Examiner-Andrew V. Kundrat Attorney-Connolly and Hutz ABSTRACT: Assembly comprises eyelet in form of shaft with series of lugs mounted on shaft. Each lug includes looped end portion of same thickness that loosely surrounds shaft and coplanar end portion of same thickness as looped portion. Looped portions of lugs contact one another in line on shaft. At least one of end lugs in line includes additional portion connected and equal in thickness to its coplanar end portion with additional portion offset in direction of adjacent lug in line.

EYELET AND LUG ASSEMBLY CROSS REFERENCE TO RELATED APPLICATION The present application is a division of pending application Ser. No. 735,259,'filed June 7, 1968 and now US. Pat. No. 3,520,981.

BACKGROUND OF THE INVENTION The present invention relates to apparatus for classroom physics experiments, and more particularly to apparatus for use in demonstrating equilibrium phenomena.

Prior to the present invention, numerous structural arrangements have been proposed for the purpose of demonstrating phenomena associated with the classroom instruction of physics. For the most part, many of these arrangements are characterized by their complex mode of operation as well as the expense of their overall construction. Moreover, and most important, is the fact that many of the heretofore available structures for use in demonstrating phenomena associated with the classroom instruction of physics fail to function properly. Often, the data formulated during the demonstration or experiment is thrown off by the improper operation of the structures comprising the experimental equipment. For example, in an equilibrium experiment the forces must be coplanar in order to obtain the best data. When the forces are not coplanar the data collected during the demonstration is inaccurate in proportion to the amount the forces deviate from the required coplanar relationship.

Accordingly, it is an object of the present invention to avoid the above disadvantages and provide apparatus for classroom physics experiments which is simple to operate and maintain, inexpensive and reliable.

SUMMARY OF THE INVENTION In accordance with present invention, dependable equilibrium experiments are easily conducted with a unique eyelet and lug assembly. The eyelet is in the form of a shaft with a series of lugs mounted thereon. Each lug includes a looped portion of the same thickness that loosely surrounds the shaft, and a coplanar end portion of the same thickness as a looped portion. The looped portions of the lugs contact one another in a line on the shaft. At least one of the endlugs in the line includes an additional portion connected and equal in thickness to its coplanar end portion with the additional portion ofi'set in the direction of the adjacent lug in the line. This assembly enables the application of coplanar forces to the eyelet.

In the case of four lugs mounted on the eyelet, the two end lugs each have an additional portion connected and equal in thickness to its coplanar end portion with the additional portion of each end lug offset in the direction of the inside lug adjacent to it.

BRIEF DESCRIPTION OF THE DRAWING Novel features and advantages of the present invention in addition to those mentioned above will become apparent to one skilled in the art from a reading of the following detailed description in conjunction with the accompanying drawing wherein similar reference characters refer to similar parts and in which:

FIG. I is a front elevational view of an apparatus utilizing an eyelet and lug assembly according to the present invention;

FIG. 2 is an exploded view of the eyelet and lug assembly according to the present invention; and

FIG. 3 is a top plan view of the eyelet and lug assembly of the apparatus shown in FIG. 1.

DETAILED DESCRIPTION OF THE INVENTION The drawing illustrates an eyelet and lug assembly 400, and more specifically a particular use of this assembly for studying coplanar concurrent forces in equilibrium. The eyelet and lug assembly comprises an eyelet in the form of a shaft 402 with a series of

lugs

404, 406, 408 mounted on the shaft 402. Each of the lugs includes a looped portion 410 of the same thickness, and each looped portion loosely surrounds the shaft to facilitate rotation of the lugs about the shaft. Moreover, when the lugs are mounted on the shaft the looped portions contact one another in a line. Each of the lugs also includes a coplanar end portion 412 of the same thickness as a looped portion. In the case of three lugs mounted on the shaft, one of the end lugs has an additional portion 414 connected and equal in thickness to its coplanar end portion 412. The additional portion 414 is offset in the direction of the lug adjacent to it in the line.

When the eyelet and lug assembly is utilized to connect four forces together in coplanar relationship a fourth lug 416 is provided. Lug 416 includes a looped portion 410 as well as a coplanar end portion 412. Additionally, end lug 416 has an additional portion 414 connected and equal in thickness to its coplanar end portion 412. Like end lug 404, the additional portion 414 on lug 416 is offset in the direction of the lug adjacent to it in the line.

Although the eyelet and lug assembly 400 has utility in other arrangements, it is particularly useful in an apparatus for studying coplanar concurrent forces in equilibrium. FIG. 1 illustrates an apparatus for conducting such a study. In this regard, a support table 420 is provided with a pair of

spacedapart supporting rods

422, 424, and each of the rods supports a pulley or bearing 425 at its upper end. In the arrangement illustrated in FIG. 1, three lugs are used to conduct the study. A string 426 is connected to the middle lug 406 and a weight 428 attached to the free end of the string. Additionally,

strings

430 and 432 are connected to

end lugs

408 and 404, respectively. These strings are trained over the pulleys 425 and

weights

434 and 436 connected to their free ends, as illustrated in FIG. 1. An adjustable protractor 438 is provided for measuring the angles of the

strings

430 and 432. The study is conducted by resolving the various forcesacting on the shaft 402 into their horizontal and verticalcomponents. The horizontal forces acting in one direction approximately cancel those horizontal forces acting in the opposite direction and the same is true of the vertical forces, which proves that the forces are in static equilibrium.

As mentioned above, the forces are in coplanar relationship with each other. This is accomplished by connecting the strings to the lugs as shown in FIGS. 2 and 3. In this regard, each of the strings passes through an opening in its respective lug. Referring to FIG. 3, string 432 passes through the coplanar end portion 412 and the additional portion 414 and is knotted at 440. Thus, string 432 is spaced two equal distances from a given side of the eyelet and lug assembly. By passing string 426 through the opening in lug 406 in the same direction as string 432 it is positioned in the same plane as string 432. Finally, by passing string 430 through the opening in its lug 408 in the opposite direction it is positioned in the same plane as the other two strings. As can readily be understood, use of the eyelet and lug arrangement enables a variety of forces to be applied to the eyelet, which forces are in coplanar relationship to one another. Moreover, if five lugs are assembled on the eyelet the fifth lug can include an additional portion twice the thickness of its coplanar end portion. The eyelet and lug assembly eliminates torque in the system it is used.

Iclaim:

1. An assembly comprising an eyelet in the form of a shaft and a series of at least three lugs mounted on the shaft, each lug including a looped portion of the same thickness that loosely surrounds the shaft and a coplanar end portion of the same thickness as a looped portion, the looped portions of the lugs contacting one another in a line on the shaft, and at least one of the end lugs in the: line including an additional portion connected to and equal in thickness to its coplanar end portion with the additional portion offset in the direction of the adjacent lug in the line so as to provide a surface substantially coplanar with the abutting surfaces of the adjacent two lugs.

tion with the additional portion of each end lug offset in the direction of the lug adjacent to it

Claims

1. An assembly comprising an eyelet in the form of a shaft and a series of at least three lugs mounted on the shaft, each lug including a looped portion of the same thickness that loosely surrounds the shaft and a coplanar end portion of the same thickness as a looped portion, the looped portions of the lugs contacting one another in a line on the shaft, and at least one of the end lugs in the line including an additional portion connected to and equal in thickness to its coplanar end portion with the additional portion offset in the direction of the adjacent lug in the line so as to provide a surface substantially coplanar with the abutting surfaces of the adjacent two lugs.

2. An assembly as in claim 1 wherein the series comprises four lugs, the two end lugs each having an additional portion connected to and equal in thickness to its coplanar end portion with the additional portion of each end lug offset in the direction of the lug adjacent to it.