US2923569A

US2923569A - Pipe lifting tool

Info

Publication number: US2923569A
Application number: US769476A
Authority: US
Inventors: Milliron Hilbert
Original assignee: Individual
Current assignee: Individual
Priority date: 1958-10-24
Filing date: 1958-10-24
Publication date: 1960-02-02
Anticipated expiration: 1977-02-02

Description

Feb. 2, 1960 H. MILLIRON PIPE LIFTING TOOL Filed Oct. 24, 1958 INVENTOR. Hilbert L.Mil|iron ATTORNEY,

PIPE LIFTING TOOL Hilbert Milliron, Pittsburgh, Pa., assignor of one-third to. Paul Felix and one-third to William J. Ruano, both of Pittsburgh, Pa.

Application October 24, 1958, Serial No. 769,476

2 Claims. 01. 294-106 r This invention relates to a tool for lifting large pipesand, more particularly it relates to a clamp-like tool for engaging the inner surface of large cementitious pipes so as to enable lifting of the pipes axially and positioning of them in manholes, sewers and the like. i r

An outstanding disadvantages of tools for engaging large pipes such as used in sewers, manholes and the like, is that they are unduly cumbersome, also they do not enable the operator to control accurately the lifting and placing movements of the pipe. Generally, a chain is wrapped around a large pipe in order to lift and move it into place. However such chain has proved unsatisfactory since the pipe cannot be held steadily and-placed accurately, particularly vertically, and. often times will twist around in an undesired direction. x 2

An object of my invention is to provide a noveltool for engaging the inner surfaces of pipes of large diameter to enable lifting of the pipes by cranes or other power operated machines and to enable easy removal or accurate placement thereof when constructing manholes and the like, which tool will obviate the above mentioned disadvantages of conventional devices.

A further object of my invention isto provide a pipe lifting tool for large pipes, which enables the lifting thereof as well as turning of the pipe along its axis, also which prevents abnormal swaying when the pipe is dangling from said tool.

Other objects and advantages of my invention will become apparent from a study of the following specification taken with the accompanying drawing wherein:

Fig. 1 is a cross-sectional view of a pipe showing a tool embodying the present invention clamped to the inner surface of the pipe.

Fig. 2 is a fragmentary, vertical, cross-sectional view taken along line IIII of Fig. 1.

Fig. 3 is an enlarged, fragmentary, perspective view showing the upper portion of the chain suspension in Fig. 2.

Fig. 4 is an enlarged, fragmentary view showing the bottom portion of the suspension in Fig. 2; and

Fig. 5 is a fragmentary, enlarged, perspective view showing one of the pipe-engaging shoes illustrated in Fig. 2.

Referring more particularly to the drawing, numeral 18 denotes a large pipe of cementitious material, such as one of several feet in diameter, for the construction of manholes, sewers and the like.

The tool embodying the present invention for clarnping onto said pipe comprises'a base plate 1 of triangular or other desired outline. Integrally welded or otherwise secured to the three corners of base plate 1 are

brackets

2, 3, and 4, which serve as bearings for pivotally mounting arms, such as 4a. There are three such arms illustrated. Arms 4a may be adjustably extended in length by providing suitable holes and bolts 20 as illustrated in Fig. 5 in order to accomodate pipes of difierent diameters. At the end of arm 4a there is provided shoes, such as 5, similar to brake shoes and of a curvature 2,923,569 Patented Feb. .2, 1960 approximatingthat of the inner surface of the pipe.

However, in some instances shoes 5 may be omitted and the end of arm 4a may engage the pipe surface directly. Base plate 1 is suspended by means of a hook 14 which may be attached-to the boom of a crane or other power lifting machine (not shown).' Wire cable 12 has a top loop portion 13 which is provided by means of clamps 13a and has a similar bottom loop portion 12a. Suspended from the bottom loop 12a is an eye bolt 16 which links loop 12a and has a bolt 17 screw threaded thereto which engages the bottom surface of plates 1.

A ring 10 is clamped by means of a set screw 11 to any desired intermediate portion of the chain 12. Ring 10 provides a bearing support for ring 9 resting thereon which has secured thereto one end of the chain 6, the

other end of the chain having a hook which engages one of the arms 4a. Three such chains, such as 6, are provided, one for each arm 4d. It should be understood,

howeventhat whilethree arms are illustrated that the be increased to 4 or any other desired number may numb er.

and dot outline when the tool is to be lowered into a vertically mounted pipe which is resting on the ground.

After the tool has been lowered, the arms 4a may be extended outwardly to'the' position shown in full lines.

By subsequently lifting ,hook 14, the arms 4a firmly-engage and are clamped to the=inner surface portions of the pipe." It should be particularly noted that arms 4a do not extend quite horizontally but are disposed at a very small angle with respect to base plate 1, perhaps of the order of 10 to 15 degrees or less. Thus when the hook 14 is lifted together with wire rope 12 there will result a firm clamping onto the interior surface of the pipe because arms 4a are almost straightened out. It is far less desirable to allow arms 4a to move to a degree or greater than 90 degree angle with respect to wire rope 12 since it would be very difiicult to remove the tool or suspension from the pipe after it is lowered into place. After the shoe portions 5 of arms 4a engage the inner surface of the pipe 18, hook 14 is lifted so as to lift the pipe axially in a vertical direction and thereafter the pipe may be moved to and lowered to any desired position. Thereafter, the tool may be released merely by lowering the hook 14 and pivotally moving the arms 4a to the dash and dot line position.

Another important feature of the invention resides in the fact that the pipe is swivelly mounted by virtue of the specific suspension of the tool. More specifically, base plate 1 may rotate on the nut 17, or perhaps on a washer (not shown) intermediate said nut and plate. The arm assembly including plate 1, arms 4a, chains 6 and ring 10 may be spun around wire 12 as an axis at which time ring 9 rotates on top of ring 10 so as to turn the pipe to any horizontal angular position desired. Chains 6, even when arms 4a are in clamping engagement with the pipe, are not under tension.

The purpose of chains 6 is not to hold the arms 40, normally, but for the purpose of preventing rocking of the pipe in a vertical plane while it is being lifted or lowered so as not to allow it to get out of control.

The pipe lifter or tool according to the present invention provides a very firm and reliable clamping grip on the inner surface of the pipe and causes the pipe to remain stationary and to be moved solely in an axial direction, also to enable rotation of the pipe about its axis when desired.

Thus it will be seen that I have provided a highly eflicient tool for clamping onto and lifting large pipes during construction of manholes, sewers and the like, which tool is relatively simple in construction and oper- 3 ationand which enables lifting of the pipe axially, also which enables turning of the pipe about its own axis, and which substantially prevents rocking or swaying 'movements of the pipewhen v it is beingmoved, into;

pasit onr Whilelyhave illustrated anddescribed ar single, specific:

embodiment of my invention, it will ,be understoodthat this is by way of, illustrationonly, and that various changes and modifications may be made WlthllLthCflCOl'k templation of my invention-andwithin the-scope of the following claims.

I claim;

1, A pipe 1iftiug; tool,comprisinga base-plate; an

eye bolt extending through a hole in the center of said Plate, a cable having. a lower loop extending through the eye of said bolt, a nut threaded to said bolt underneath said plate so that the plate will be rotatable about the axis of saidbolt, a plurality of arms pivotally mounted on equally spaced, peripheral portions of said plate, means, for adjusting the length of-said arms, a ringrof largerpinnerdiameter than said cable and freelymounted forrotation about an intermediate portion of said-cable,

a second-ring adjustably mounted in height about said,

cable and serving as a bearing support for said first mentioned ring, a plurality of chains, each havingone end connected to said ring and the other end connected to an intermediate portion; of one of said arms, said arms being of such length that when said cable and plate are loweredaxially inside the pipe and the arms are pivotally extending radially outwardly, they will engage the inside surface of saidpipe when making an angle. of less thanabout:li5-"- with: the plate, so that upon lifting said cable, saidarms will, clampingly. engage the pipe. by toggleaction;

and liftit axialIy said chains being untensioned during such lifting moveme. t and serving as limit stops for preventing excessive sway of the pipe as it is being lifted or lowered.

2. A pipe lifting tool comprising a base plate, a swivel connector extending upwardly through a hole in the center of said plate, flexible suspending means for supporting said swivel connector, a, plurality of arms pivotally mounted on equally spaced, peripheral portionsof said plate, a ring rigidly=secured to an intermediate portion" of 'said flexible suspending means, a second ringf'surrounding said flexible suspending means and directly supportedlon said first-ring, the inner diameter of said second ring being larger than the diameter of said flexible suspending means, a plurality of flexible connectors having one end connected to said second ring and the other end connected to an intermediate portion of one of said arms; said 7 arms being of such length that their extremities will engage the inside surface of. the-pipe. when;

making. an angle ofless than 15 with saidtplate and said; plurality offiexible connectors being untensioned. when said arm extremities engage the pipe so as to serve;

solely as, stop elements to prevent excessive rocking of the pipeiwhen lifted or lowered.