Spring loaded grabbing and hoisting tongs

Tongs for the gripping of articles to be displaced and operable between an open relation in which an article to be displaced can be received and a collapsed relation in which a received article is seized between cooperative gripping members for displacement. Comprising the tongs is a pair of L-shaped lifting arms pivotally secured at their upper ends to a central lifting eye. Lower legs of the lifting arms extend parallel and spaced apart from each other and extend to opposite gripping members at their distal ends. The gripping members are biased toward a collapsed relation in which to grip a received article by a pair of oppositely connected springs in tension. Opposing collapse of the lifting arms and gripping members are a pair of trigger arms each laterally secured from an opposite lifting arm and both pivotally secured to an intervening arm-stop which also restricts displacement of the gripping members between the open and collapsed relation of the tongs.

BACKGROUND OF THE INVENTION 
1. Field of the invention 
This invention relates to tong structures for seizing and lifting of 
articles. 
2. Description of related art including information disclosed under 37 CFR 
.sctn..sctn.1.97-1.99. 
Tongs and tong-like structures for the retrieval and transfer of articles 
have been widely used for well over a century. They are available in a 
variety of structural forms for both general and specific applications. 
Exemplifying tongs of the prior art are the disclosures of prior U.S. Pat. 
Nos. 596,908; 1,132,003; 1,376,414; 1,485,972; 1,782,326; and 1,909,788. 
In a typical construction, tongs resemble a large scissors with end 
gripping members extending inward toward each other for gripping or 
seizing an article. A chain or rope can be connected via a center loop to 
a hoisting ring. Depending on orientation and method of operation, the 
tongs can be utilized to lift, seize, or hold an article for retrieval 
and/or transport. 
SUMMARY OF THE INVENTION 
The general object of the invention is to provide a novel tongs structure 
operable between open and collapsed relations for the gripping and 
hoisting of articles. In general, the object is achieved by a pair of 
opposite lift arms each being of substantially L-shape and pivotally 
secured at their upper end to a centrally located lifting eye. In the open 
orientation of the tongs, each L-shaped arm includes a first leg extending 
oppositely in a common plane to an offsetting second leg that terminates 
at its distal end inwardly directed as a prong or other suitable gripping 
member. 
A pair of elongated springs arranged in a crossing pattern are each 
connected in tension between the first upper leg of one lift arm to the 
second lower leg of the other lift arm. A pair of aligned trigger arms 
each laterally extending pivotally secured from the second leg of a 
respective lift arm are commonly joined at their inner ends to a centrally 
located arm stop. 
With the tongs in a more or less horizontal orientation and in the open 
relation the arm stop serves to maintain the trigger arms in a near linear 
relation centrally slightly below center so as to maximize the spread 
between the lift arms. Placing the tongs in a vertical orientation enables 
self-weight of the structure to push the trigger arms upwardly over and 
past center so as to permit the springs to collapse the lift arms and draw 
the gripping members toward each other. Supplying a draw force such as by 
a chain or rope secured to the lifting eye, similarly causes the lift arms 
to be drawn toward each other. 
The above, as well as additional objects, features and advantages of the 
invention will become apparent in the following detailed description.

DESCRIPTION OF THE PREFERRED EMBODIMENT 
Referring to the drawings, the tongs hereof are designated 10 and include a 
center lifting eye 12 to which a pair of cooperating and opposite lift 
arms 14 and 16 are pivotally secured. Each lift arm is L-shaped and both 
include a coplanar first leg 18 extending when in the open relation 
oppositely rectilinear from the eye. Offset depending second legs 20 
extend spaced apart and parallel to each other. At the terminal distal end 
of each second leg is an inwardly pointed gripping prong 27 or other 
suitable gripping structure adapted to grip or minimally penetrate an 
article to be retrieved or lifted. 
Urging collapse of the opposite lift arms toward each other are a pair of 
elongated elastomeric springs 22 and 24. The springs are arranged in a 
crossing pattern and are secured tensioned at each of their ends by an S 
hook 26. In this arrangement, the first leg 18 of one lift arm is 
connected via a spring to the second leg 20 of the other lift arm. 
Opposing the biasing force of the springs 22 and 24 toward collapse of the 
tongs are a pair of trigger arms 28 and 30 serving to maintain the open 
spread between the lift arms until the tongs are to be utilized as will be 
understood. The individual trigger arms are each pivotally supported from 
one of the lift arms via a pin 32 and are centrally joined in a toggle 
relation to a central arm stop 34. In this relation, with the lift arms 
spread apart, the arm stop positions trigger arms about 10 degrees below 
center. When the tongs are to be utilized, the trigger arms are caused to 
pass through center in the course of collapsing the spread between the 
lift arm prongs 27. Inward displacement of the prongs 27 during collapse 
is limited, as will be explained. 
As best seen in FIG. 6, lift eye 12 is comprised of a clevis yoke in which 
to receive the overlapping tongue ends 36 and 38 of the opposite lift arms 
to be secured pivotally thereat via a cross pin 40. A through aperture 42, 
near the upper end of the clevis enables receipt of a draw force via a 
rope or chain or even a finger. 
The arm stop 34 is best seen in FIG. 7 and is comprised of an angle section 
that includes a horizontal upper ledge 44 and a vertical leg 46. Located 
in the vertical leg are three spaced-apart apertures the outside ones of 
which-are adapted to receive pins 48 and 50 to secure the distal ends of 
trigger arms 28 and 30 respectively. Inward displacement of the prongs 27 
in the course of collapsing the tongs is limited by engagement between the 
squared distal end 52 of arm 30 when engaging the underside of arm ledge 
44 (see FIG. 8). Likewise, outward displacement is limited by engagement 
between the upper edge of arm 30 and the undersurface of arm stop ledge 
44. 
Use of the tongs hereof for seizing a carton or other suitably grasped 
article 54, can best be understood by reference to FIG. 8. Being 
constructed of metal or reinforced plastic, the tongs enjoy some amount of 
self weight. By placing the tongs in a vertical orientation while held at 
eye 12, the weight thereof effectively pushes the trigger arms 28 and 30 
in a toggle relation past center. When this occurs, the tensioned springs 
22 and 24 act to draw the lower legs toward each other until stopped by 
engagement between the distal corner 52 of trigger arm 30 and the 
underside of arm-stop ledge 44. In the course of being displaced, the 
prongs 27 are enabled to grasp the article 54 previously received 
therebetween. With a rope or chain 56 secured in aperture 42 the article 
can conveniently be hoisted and transported to a suitable destination. 
Where used for retrieval, as from a horizontal bin, the tongs can be 
oriented horizontally and caused to collapse by drawing on eye aperture 
42. 
Being that the tongs hereof are convenient to use, a considerable saving is 
realized in both time and labor enabling one person to retrieve and 
dispose of various, articles with minimal effort. 
Since many changes could be made in the above construction and many 
apparently widely different embodiments of this invention could be made 
without departing from the scope thereof, it is intended that all matter 
contained in the drawings and specification shall be interpreted as 
illustrative and not in a limiting sense.