US 3883934 A
A wire spring clip having a pair of arms or legs interconnected adjacent one end and projecting therefrom in spaced relation relative to one another with each of the legs having a helical portion formed therein to receive a post when brought into alignment against the resiliency of the clip. One of the legs has a portion protruding therefrom terminating in an open-throated eye for receiving and holding a reference datum or string line. The clip is placed on a post and frictionally retained thereon by the resiliency of the clip with the eye portion spaced from the post and adjustable by sliding the clip longitudinally along the post or turning it about the axis of the post. A string line extends from one eye to another providing a reference datum to control construction machinery utilizing sensors and automatic height and level control.
Description (OCR text may contain errors)
[ May 20, 1975 0 United States Patent [191 Rochfort 1 WIRECLIP  Inventor: William P. K. Rochfort, Fargo, N.
Dak. 58102  Filed: Nov. 5, 1973  Appl. No.: 413,174
 U.S. Cl. 24/261 R; 404/84  Int. Cl A44b 21/00  Field of Search 256/32, 47, 57; 404/84; 24/261 R, 261 PT, 252 TH  References Cited UNITED STATES PATENTS 637,634 11/1899 Martz 256/57 939,520 11/1909 Leyner 24/261 R 3,239,195 3/1966 Todd et al. 256/47 3,302,328 2/1967 King 24/261 PT Primary Examiner-Donald A. Griffin Attorney, Agent, or FirmStanley E. Johnson  ABSTRACT A wire spring clip having a pair of arms or legs interconnected adjacent one end and projecting therefrom in spaced relation relative to one another with each of the legs having a helical portion formed therein to receive a post when brought into alignment against the resiliency of the clip. One of the legs has a portion protruding therefrom terminating in an open-throated eye for receiving and holding a reference datum or string line. The clip is placed on a post and frictionally retained thereon by the resiliency of the clip with the eye portion spaced from the post and adjustable by sliding the clip longitudinally along the post or turning it about the axis of the post. A string line extends from one eye to another providing a reference datum to control construction machinery utilizing sensors and automatic height and level control.
8 Claims, 4 Drawing Figures PMENIE HAYZO I975 1883.934 SHEET 1 OF 3 PATENTEB HAYZO I975 SHEET 3 OF 3 WIRE CLIP This invention relates to an endless wire spring clip with an extension thereon for holding a string or reference datum line and to the combination of a plurality of such spring clips arranged one on each of a series of posts and having a string line supported by the clips along a selected path.
Wire-type spring clips are known and also it is known to support a string line on a series of posts for use, as for example, in providing a datum line externally of a curb and gutter slip former wherein sensors contacting the line provide height and level adjustment for the machine as it travels along the same path as the line and to one side thereof.
The known wire and spring clips are provided for fastening tags or the like to a backing member, or alternatively, of the clothespin type, to fasten an article to a line such as a clothesline. In such type of spring clips, there is no provision for passing a post through aligned portions of the clip and having a further portion extending therefrom to which is attached, in a detachable manner, a string line. In the prior art post and line combinations, the members for holding the line on the posts are complicated, and require considerable effort in placing the members on the posts adjusting the position to place the line along the desired course.
A principal object of the present invention is to provide a simple spring clip assembly of the wire type which may be fastened to a stake or post member and held thereon through the shape and resiliency of the clip.
A further principal object of the present invention is to provide a wire clip which may be readily placed on a stake or a post and conveniently adjusted for height and/or vary the distance of the protruding portion, placing a string line attached thereto and extending from one post to another at various selected elevations and/or path of travel.
Accordingly, there is provided in accordance with the present invention a wire clip comprising (a) a pair of legs arranged at an angle to one another; (b) means interconnecting the legs adjacent one end thereof; a helical portion in each of the legs at a position spaced from the position at which the legs are interconnected, the helical portions having substantially at least one helix for embracing a post member and arranged with their axes substantially parallel to one another and offset laterally in a normal at rest state of the clip; (d) a further leg portion extending from one of the helical portions and terminating in an open throated eye; and (e) means resiliently resisting movement of the helical end portions from their at rest offset relative positions to a position wherein their respective axes are substantially coincident with one another.
The invention is illustrated by way of example in the accompanying drawing wherein:
FIG. 1 is an oblique view of a clip constructed in accordance with the present invention on respective ones of a pair of adjacent posts and supporting a string line from a free end thereof;
FIG. 2 is a top plan view of the clip in FIG. 1 but shown in an at-rest state;
FIG. 3 is a side elevational view of FIG. 2; and
FIG. 4 is similar to FIG. 1 illustrating a modified clip.
Shown in FIG. 1 are two posts of a series of posts or stakes driven into the ground and each having a wire clip 20 frictionally held thereon and supporting a string line 30 on a free end portion of the clip which projects laterally beyond the post. The line 30 may be a wire, cord or the like hereinafter referred to as a string line utilized as a reference datum for construction machines having automatic height and level control, as for example, disclosed in U.S. Pat. No. 3,249,026, issued May 3, 1966 to J. Curlett et al. The string line 30 is supported by the posts 10 spaced at intervals to one side of a path along which the constuction machine travels. The machine carries sensors having feelers which contact the string line. The string line is preset appropriately by adjusting the clips on the post providing a grade line and path for the machine to follow.
The clip 20 is a single length of resilient steel or plastic wire bent to provide legs 21 and 22 extending outwardly from and interconnected by a coiled or helical portion 23. The legs 21 and 22 have respective coil or helical portions 24 and 25 each formed with at least one helix (preferably open) and when brought into alignment against the resilient spring pressure of legs 21, 22 receive post 10 engaging the same at positions spaced longitudinally along the post. The helical portion 24 terminates in a free end 26 adjacent the post and the helical portion 25 has a further leg 27 extending outwardly from the post in a direction angularly related to the direction which legs 21 and 22 radiate out from the post. The leg 27 has a hook portion 28 adjacent the free end thereof, providing an eye 29 for receiving and holding the string line 30. The hook portion 28 has an extending portion 28a which projects beyond the leg portion 27 terminating in an end 31. The hook end extending portion 28a and the projecting leg portion 27 are offset from one another providing a throat through which the string line 30 may be readily placed into the eye 29.
From FIG. 2, it will be seen the legs 21 and 22 of the clip are, in an at-rest position, laterally offset from one another and, accordingly, to place the clip on the post, it is necessary to press the arms 21 and 22 generally in a direction toward one another against the resilient bias of the spring, bringing the helices 24 and 25 into axial alignment.
FIG. 3, a side elevational view, illustrated the arms 21 and 22 as being offset from one another corresponding to a direction longitudinally along the length of the post 10 in FIG. 1. If desired, the axis of helical portions 24 and 25, designated in FIG. 3 respectively A and B, may be slightly inclined relative to one another sloping in opposite directions relative to the axis of helical coiled portion 23 such that in placing the clip on the post the arms must be deflected in a direction generally towards one another as viewed in FIG. 3, bringing the axes A and B coincident with one another for receiving the post. This places the spring under compression in each of two directions, when placed on the post, thereby firmly holding the clip on the post by frictional engagement therewith.
In the embodiment illustrated, helices 24 and 25 are arranged with respect to the helical portion 23 such that the legs 21 and 22 crisscross in plan view when the helices 24 and 25 have a post 10 inserted therethrough. The helices 24 and 25 are wound in opposite directions. However, if desired, they may be wound in the same direction.
To place the clip on the post 10, the legs 21 and 22 are pressed together against the resiliency thereof,
bringing helical portions 24 and 25 into alignment along a common axis and spaced apart longitudinally therealong with respect to one another. The helical portions are then slid over the top end of the post and placed in an approximate position. A string line is threaded throughtheeyes of clips on the posts. To bring the line into the desired elevation, the clips are slid as required longitudinally along the post. To place the line in a final adjustment along the desired path, the clips are rotated about the axis of the post on which they are mounted.
In the foregoing spring clip, the loops provided by respective spiral portions 24 and 25 may be of slightly different radii if desired. The loop provided by spiral 24 may, if desired, be slightly larger than the diameter of the post while the loop provided by spiral 25 may be the same size or even slightly smaller than the post. The latter loop may be readily enlarged by using legs 27 and 22 as lever arms to open the helix 25 increasing its diameter during placing the same over the post. On letting go, the helical portion 25 will frictionally engage the post holding the clip in position thereon. During repeated use of the posts, the upper end may become burred from hammering the post into the ground and to allow for the same, the upper helical portion 24 may initially be made somewhat larger than the diameter of the post.
Referring to FIG. 4, there is illustrated a modified clip 50 mounted on respective one of a series of posts 10. Each clip consists of legs 51 and 52 interconnected at one end by a helical portion 53. Spaced from the helical portion 53 on the respective legs 51 and 52 are further helical portions 54 and 55 having their respective axes substantially in alignment for receiving the post 10. A continuation of the helical portion 55 provides a further leg 56 extending from the post substantially in the same direction as the legs 51 and 52. The leg portion 56 projects from the post 10 to a greater extent than the helical portion 53 and terminates in an open hooked eye 57 for receiving a string line 30. The leg portions 51 and 52, when the clip is mounted on a post, contrary to the embodiment in FIG. 1, do not cross one another but, instead, in plan view, are substantially parallel to one another. The legs 51 and 52 are in a state of tension as in the previous embodiment when the clip is mounted on the post 10 by virtue of having helical portions 24 and 25 offset in plan view in an at-rest state as viewed in FIG. 2.
In the embodiment illustrated in FIG. 4, leg 56 further is in tension from its engagement with the helical portion 53 and which tension is provided by the helical spring portion 55. Disengagement of the leg 56 from the helical portion 53 would result in the eye portion 57 moving to the right as viewed in FIG. 4 for an at-rest position. The helical portion 53, accordingly, provides effectively a rest for the leg 56 stabilizing the same providing a more rigid arrangement for holding the string line.
1. A clip comprising:
a. a pair of legs arranged at an angle to one another;
b. means interconnecting said legs adjacent one end thereof;
c. a helical portion in each of said legs at a position spaced from the interconnection of said legs, said helical portions having substantially at least one helix for embracing a post member and arranged with their axes substantially parallel to one another and offset laterally in a normal at-rest state of the clip, said helical portions further being offset in a direction parallel to said axes;
d. a further leg portion extending from and substantially beyond one of said helical portions, said further leg portion terminating in a free outer end having an open throated eye radially spaced from a post member passing through and embraced by said helical portions; and
means resiliently resisting movement of the helical end portions fromtheir at-rest offset relative positions to a position wherein their respective axes are substantially coincident with one another.
2. A clip as defined in claim 1 wherein said legs and helical portions are a continuous length of wire made of springy material.
- 3. A clip defined in claim I wherein said means interconnecting the legs comprises a further helical portion.
4. A wire clip as defined in claim 1 wherein one of said pair of legs and said further leg project substantially radially in opposite directions from the axis of the helical portion associated therewith.
5. A wire clip as defined in claim 1 wherein one of said pair of legs and said further leg project generally in the same direction from the axis of the helical por' tion associated therewith.
6. A clip formed from a single length of springy wirelike material and having a pair of legs interconnected at one end by a first helical portion, a second and third helical portion in respective ones of said pair of legs at a position spaced from said first helical portion, the axis of said second and third helical portions being substantially parallel to one another and laterally offset in a clip at-rest state, said second and third helical portions further being offset from one another in a direction parallel to said axes, and a further portion extending from one of said second and third helical portions and projecting therefrom beyond and generally in the same direction as the leg associated with such helical portion, said further leg portion terminating at the free end in an open-throated eye having the axis thereof transverse i the axes of the helical portions and offset therefrom.
7. A datum line for use with sensors on a construction machine to control height, level and/or steering thereof during movement of the machine, comprising: a plurality of posts disposed in vertical relation at longitudinally spaced intervals along and to one side of a path to be followed by the machine, a spring clip on each of said posts comprising a pair of legs interconnected adjacent one end thereof and having a helical portion in each of the legs at a position spaced from the interconnected portion, said helical portions receiving a post therein and located respectively at spaced-apart position longitudinally along the post, a further leg member extending from one of said helical portions and projecting away from the post, said further leg member terminating in an open-throated eye free end portion spaced from the post; and a reference datum string line extending through the eye of each of said clips at a selected level and direction for engagement by feelers for said sensors to control the direction of travel, height and/or level of the machine.
8. The arrangement as defined in claim 7 wherein said clip is formed from a single length of springy wirelike material, said legs being interconnectedat said one end by a further helical portion having the axis thereof substantially parallel to the axes of said helical portions in the respective legs and wherein said further leg is resiliently biased in abutting relation against said further helical portion.