US3017905A

US3017905A - Hot line stick

Info

Publication number: US3017905A
Application number: US644148A
Authority: US
Inventors: Charles H Klein
Original assignee: National Telephone Supply Co
Current assignee: National Telephone Supply Co
Priority date: 1957-03-05
Filing date: 1957-03-05
Publication date: 1962-01-23
Anticipated expiration: 1979-01-23

Description

Jan. 23, 1962 c. H. KLEIN 3,017,905

HOT LINE STICK Filed March 5, 1957 INVENTOR. CHARLES H. KLEIN United hta tes Patent Ohio Filed Mar. 5, 1957, Ser. No. 644,143 2 Claims. (Cl. 140-113) The invention relates in general to hot-line sticks or elongated poles carrying tools for working on hot lines, that is, high voltage conductors, and relates more particularly to a combination of an elongated pole and a conduit combined therein for conducting fluid under pressure to be used in the tool or head carried on the end of the pole.

Hot-line sticks have been used by line repair and construction crews with such sticks being in the order of ten feet in length, for example, and constructed of laminated wood or other insulating material so that an operator may grasp and manipulate one end of the stick and maneuver a tool or head on the upper end of the stick to perform Work on conductors which may be energized with high voltage or be in close proximity to other conductors so energized. The work performed on such conductors may include the mechanical crimping of compression splicing sleeves on the conductors to connect together ends of two conductors. Such mechanical crimping is only satisfactory up to about No. 1 copper (.289 inch) or the equivalent conductivity in aluminum. For larger sizes a fluid operated die head or compression device has been utilized, such as in my Patent 2,533,943, issued December 12, 1950, entitled Die Head Device. The use of such hydraulic die head devices, however, is practically limited to use on the ground and, of course, when the conductors to be joined are not energized with high voltage nor are they in proximity with other conductors so energized.

An object of the invention, therefore, is to provide a hydraulically operated hot-line stick.

Another object of the invention is to provide a combined hot-line stick and conduit for fluid under pressure.

Another object of the invention is to provide a stiff hot-line stick which may be used to carry and manipulate a tool or head and which stick also contains a small bore conduit therein for supplying fluid under pressure which is utilized in the head of the hot-line stick to perform useful work.

Another object of the invention is to provide a single elongated pole which acts both as a handle for manipulating a compression tool and acts also as a conduit for supplying hydraulic fluid under pressure for operating the compression tool to compress splicing sleeves on conductors which at least are in proximity to conductors energized at high voltages.

Another object of the invention is to provide a tool to splice electrical conductors in the air which are carrying electric current or which are close to other conductors carrying electric current at high voltages.

Other objects and a fuller understanding of this invention may be had by referring to the following description and claims, taken in conjunction with the accompanying drawing, in which:

FIGURE 1 is a perspective view of the complete hotline stick; and

FIGURE 2 is an enlarged view of the head partially in section.

FIGURES 1 and 2 show the construction of the combined hot-line stick and conduit 11 of the invention. This hot-line stick 11 consists generally of an elongated pole 12 and a work head 13. The elongated pole 12 may be in the order of five to ten feet in length depending upon the voltage it is designed to withstand. FIGURE 2 Patented Jan. 23, 1&52

ice

shows that the pole 12 has a central small bore conduit 14 therein which bore is small relative to the outside diameter of the pole 12. The pole 12 is constructed without any metallic reinforcing members and is designed to have a thick enough wall section to withstand very high internal pressures. The pole 12 may be made from any of the so-called plastic materials, which may or may not be reinforced with non-conducting cord or fabric, for example, thermosetting or thermoplastic materials, having the required stiffness and bursting strength. One such material is that sold under the trade term nylon.

The work head 13 is shown to enlarged scale in FIG- URE 2 and has a generally C-shaped body' 17 containing a cylindrical bore 13 which in turn contains a movable piston 19. A piston rod 20 connects the piston 19 to a movable ram 21. A die half 22 is removably carried on the ram 21, and a mating die half 23 is carried on the upper end 24 of the C-shaped body. Reciprocation of the piston 19 thus causes the die

halves

22 and 23 to move toward and away from engagement.

As shown in FIGURE 1, the work head 13 may be used to compress a splicing sleeve 27 upon the ends of first and

second conductors

28 and 29, respectively, to join them together. The work head 13 makes a series of compressed indentations 319 along the sleeve 27 in a well-known manner to effect this electrical and mechanical splicing connection.

An internal conduit 32 connects the lower end of the cylinder 18 to the conduit 14 in the pole 12. The upper end of the pole 12 may have a suitable hydraulic fitting 33, for example, a standard high pressure hose fitting; and as part of this, a metallic insert 34 may be molded in or otherwise fixedly carried on the upper end of this pole 12. A mechanical coupling 35 forms a part of the hydraulic fitting 33 to mechanically rigidly connect the work head 13 to the upper end of the pole 12.

The lower or second end of the pole 12 carries another hydraulic fitting 36 for connection to a flexible conduit 37 which may be a standard high pressure hydraulic hose. This flexible conduit leads to a source of fluid pressure which may be either a poweroperated or manually operated pump, in this case shown as a manually operated pump 38. A valve 39 may be provided to control application of fluid pressure from the pump 38 through the conduit 37 and bore 14 to the cylinder 18. The cylinder and piston 1% and 19 constitute a fluid motor for causing movement of the die halves relative to each other to perform useful work, in this case to compress a sleeve 27 upon the

conductors

28 and 29. The die

halves

22 and 23 are removable so that die halves of different sizes may be utilized with the same clamp body 17.

In operation the hot-line stick 11 is used to compress splicing sleeves, and first another hot-line stick or another work head on the same elongated pole 12 would be used to trim off the ends of the conductors, if necessary, and to place the splicing sleeve 27 thereon. Then the work head 13 would be manipulated into position by the operator grasping the lower end of the pole 12 to position the

die halves

22 and 23 on the splicing sleeve 27. Then by operation of the handle 41B of the pump 38, fluid pressure may be built up to actuate the ram 21 and thus cause an indentation 311 on the sleeve 27. The pressure may be released by opening the valve 39, and the work head 13 may then be moved to a new location on the sleeve 27 and the operation repeated to provide another indentation and so on to complete the splice.

With voltages on the conductors 2'3 and 29 of five hundred fifty volts and less, it may be safe for an operator to use an insulated handle tool and to use rubber gloves and then work the line hot. However, in voltages upwards of one thousand volts, hot-line sticks are generally used. As the operating voltage increases, the height of the towers or supporting poles carrying the conductors also increases; and for large current capacities, the diameters of the conductors become larger. This increases the complexity of the problem because the operators are working at higher elevations above ground and at higher potentials relative to ground potential and are workng on larger diameter conductors with larger, heavier, and more cumbersome tools. In attempting to maneuver such hotline sticks, even though the line on which the operator is working may not be energized, it is usually in relatively close proximity to other lines which remain energized because only in dire emergencies may all the lines on a particular supporting pole or tower be tie-energized to permit working on only one of such lines.

The elongated pole 12 is constructed to have a sufficiently large outside diameter to have sufiicient stiffness so that the Work head 13, which may weigh up to fi ty pounds, may be raised as a cantilever load on the end of this elongated pole 12. A feature of the invention is that a central bore 14, since it is quite small relative to the outside diameter, and since it is along the axis of the pole 12, does not appreciably reduce the strength of this pole so that it has essentially the same strength as a completely solid pole. Also, the small bore gives an extra heavy wall section to withstand the pressures which may be up to ten thousand p.s.i. working pressure and up to thirty thousand p.s.i. bursting strength.

It will therefore be seen that the combined hot-line stick and conduit 11 performs two functions; namely, it permits physical manipulation or positioning of the work head 13 and also provides a means for supplying fluid under pressure such as hydraulic fluid to be utilized in the work head 13 to perform useful work.

The splicing of conductors may be effected by the operators standing on the ground, and hence being at ground potential, and with the conductor lowered sufficiently so that the operators may reach it with the hot-line stick 11. Alternatively, the operators and pump 38 may be moved to a location near the conductors on the supporting pole or tower. In such cases a platform just below the conductors may be utilized such as is often called a diving board platform. This supports the operators at an elevated position from the ground, but they may be at ground potential since the operators are supported on the tower. The pump 38 is preferably located closely adjacent the operators for easy manipulation thereof. Often the high pressure hoses 37 contain metallic reinforcement in order to withstand the high pressures involved, but this is unimportant from a safety standpoint because the hot stick 11 still provides the necessary insulation to withstand the high voltages on the

conductors

28 and 29 for safety to the operators.

Although this invention has been described in its preferred form with a certain degree of particularity, it is understood that the present disclosure of the preferred form has been made only by way of example and that numerous changes in the details of construction and the combination and arrangement of parts may be resorted to without departing from the spirit and the scope of the invention as hereinafter claimed.

What is claimed is: 1. A fluid operated tool comprising, a working head,

compression clamp jaws removably carried on said head,

a reciprocable fluid motor in said head connected to relatively move said jaws toward and away from engagement to clamp a compression sleeve upon a high voltage conductor, an elongated relatively rigid insulated handle having first and second ends, means fixedly mounting said head on said handle first end to permit maneuvering said head by said handle, a small bore longitudinally in said handle, conduit means communicating said bore and said fluid motor, fluid pump means, a flexible conduit connecting said pump means and said bore at said handle second end for fluid communicaion from said pump means to said motor, whereby said tool may be operated in safety on said high voltage conductor by an operator operating said tool by said handle second end and when said operator and pump means are established at a high potential difference relative to said conductor.

2. A hot-line stick for operating on or adjacent high tension lines comprising, a combined rigid handle and conduit having first and second ends, a pump adapted to be located at ground potential and to be operable to supply hydraulic fluid under pressure, a flexible hydraulic hose connecting said pump to the second end of said hotline stick handle to supply fluid under pressure to the conduit therein, a hydraulic clamping tool physically carried on said first end of said handle and connected in fluid communication with the conduit in said hot-line stick handle so as to be operable by the fluid pressure from said pump to compress a connecting sleeve upon first and second conductors to be joined at least adjacent high tension lines, said combined hot-line stick handle and conduit being in the order of ten feet in length with a stiffness suflicient to carry said clamping tool as a cantilever load and having an electrical resistance to withstand at least ten thousand volts per foot and with no metallic conductors therein, whereby an operator may be located near said pump and hold said second end of said hot-line stick to manipulate said hot-line stick and clamp while remaining at ground potential, and said clamp may be operable at voltages in' excess of ten thousand volts with safety to the operator.

References Cited in the file of this patent UNITED STATES PATENTS 731,145 Wilbur June 16, 1903 1,672,477 Tipsord et a1 June 5, 1928 2,182,663 Eby et al Dec. 5, 1939 2,230,498 Loos et a1 Feb. 4, 1941 2,254,613 Matthysse Sept. 2, 1941 2,493,480 Eisner Jan. 3, 1950 2,556,663 Smalley June 12, 1951 2,564,031 Rich Aug. 14, 1951 2,617,548 Falkner Nov. 11, 1952 2,688,449 Haagensen Sept. 7, 1954 2,693,218 Freedom Nov. 2, 1954 2,696,850 Peterson Dec. 14, 1954 2,731,656 Payne Jan. 24, 1956 2,772,715 Neijstrorn et al. Dec. 4, 1956