US2739850A

US2739850A - Telescopic tower jack

Info

Publication number: US2739850A
Application number: US322873A
Authority: US
Inventors: Thomas H Hollingsworth
Original assignee: Individual
Current assignee: Individual
Priority date: 1952-11-28
Filing date: 1952-11-28
Publication date: 1956-03-27
Anticipated expiration: 1973-03-27

Description

9 ATTOQUEYS INVENTOR. Holll't lgsll/OPf/Z T. H. HOLLINGSWORTH TELESCOPIC TOWER JACK 2 Sheets-Sheet l I I momasfl 2 m. m m D E f. Ma r E! M.\ a W 5 2. J/ lfil 1 w 4 w o p March 27, 1956 Filed Nov. 28, 1952 March 1956 T. H. HOLLINGSWORTH 2,739,350

TELESCOPIC TOWER JACK 2 Sheets-Sheet 2 Filed NOV. 28, 1952 INVENTOR. mamas flizollg'izgswfifi ATTOEA/EKS TELESCOPIC TOWER JACK Thomas H. Hollingsworth, Moulton, Ala. Application November 28, 1952, Serial No. 322,873

2 Claims. (Cl. 304-29) This invention relates to an improved telescopic tower scaffold and means for holding the sections thereof in extended relation.

A main object of the invention is to provide a novel and improved extensible telescopic tower scaffold which is simple in construction, which is easy to manipulate, and which may be rapidly extended from its lowered position to and held in raised positions with a relatively small amount of manual effort.

A further object of the invention is to provide an improved scaifold means for extending a telescopic tower of the type employed for supporting a television antenna or the like, the improved scaffold means being inexpensive to construct, being easy to appy to a telescopic tower, being usable either for raising the tower or for lowering same to permit repair operations to be performed on the antenna, greatly reducing the cost of erection of the tower, and requiring a minimum amount of labor in elevating or lowering a tower.

Further objects and advantages of the invention will become apparent from the following description and claims, and from the accompanying drawings, wherein:

Figure 1 is a side elevational view of an extended telescopic tower scaffold provided with cable means according to the present invention.

Figure 2 is an enlarged side elevational viewshowing a modified form of scaffold means according to the present invention.

Figure 3 is a horizontal cross sectional view taken on the line 33 of Figure 2.

Figure 4 is a vertical cross sectional view taken through the telescopic tower with the sections thereof substantially in nested positions, namely, with the tower in a lowered position.

Figure 5 is an enlarged vertical cross sectional detail view taken through one of the anchoring members employed to clampingly engage an outer telescopic section of the tower while an inner section is being elevated by the cable means.

Figure 6 is a top plan view of the clamping member illustrated in Figure 5.

Referring to the drawings, and more particularly to Fig. 1, the illustrated scaffold comprises a telescopic tower 11 comprising a plurality of telescoped extensible tubular sections, shown for example at 12 to 16, the

sections

13, 14 and 15 being provided at their upper end portions with outwardly projecting pairs of diametrically opposed

stop pins

17, 17 adapted to limit the downward movement of the respective sections relative to the subjacent sections by abutment with the top edges of the subjacent sections, as shown in Figure 4. The top section 16 is provided at its top portion with a transverse stop pin 18 which is adapted to engage the top edge of the subjacent section 15, as shown in Figure 4, to limit downward movement of the top section 16 into the section 15.

Designated generallly at 19 is a frame adapted to be secured to' an outer telescopic section, such as, for example, the outermost or lowermost telescopic section 12,

States Patent 0

ice elements

20, 21 of the frame being connected by respectivevertical

post members

24 and 25 which rise substantial distances above the upper

horizontal frame members

20 and 21. The

frame members

20 and 21 are further connected by

transverse bolts

26 and 27 extending across the frame at the intermediate portion thereof, the

bolts

26 and 27 being located at opposite sides of tower 11, such as for example, the outer section 12 of the tower, as illustrated in Figure 3, whereby the

members

20 and 21 may be clamped tothe section 12 by tightening the nuts 28 on the

respective bolts

26 and 27.

Posts

24 and 25 are fixed to and rise from opposite ends of the frame 19, the post 25 being taller than the post 24. Connected to the top end of the post member 24' by a chain 29 is a holding clamp member 30 which is adapted to engage around an inner telescopic section, such as the section 13, located adjacent to the outer section 12. As shown in Figures 5 and 6, the clamping member 30 comprises a first arcuate plate element 31 provided with an integral, elongated apertured lug 32 to which the chain 29 is adapted to be connected.

A lifting arcuate plate member 33 is connected at its secured together by fastening bolts 34 as illustrated. The respective ends of the plate members 31 and 33 may be each provided with a plurality of apertures 35 through which the fastening bolts 34 may be selectively engaged in order to provide a desired resultant size of the aperture between the arcuate edges of the plate members 31 and 33. As shown in Figure 5, the clamping member 30 is engageable around the telescopic section and clampingly engages the telescopic section when the clampingmember is tilted.

The post member 25 rises somewhat higher than the post member 24 and is provided at its top end with a pulley 36, said pulley being rotatably supported in any suitable manner on the top portion of the post member 25. Extending over the pulley 36 is a cable 37 having secured to its end a second clamp member 30 adapted to clampingly engage the telescopic section above the first-mentioned clamp member 30, as shown in Figure l. The opposite end of the cable 37 is connected to a drum of a winch 38, said winch being mounted on a suitable clamping bracket 39 which is adjustably secured to the lower most telescopic section 12, as shown in Figure 1.

In the modified form of the invention illustrated in Figures 2 and 3, the winch 38 is rigidly secured to the lower portion of the post member 25 and is thus carried directly by the frame 19. As shown in Figure 3, the winch 38 may comprise a vertical'channel 40 having its web welded to the post member 25, said vertical channel having journaled therein the winch reel 41 which carries the gear 42. A suitable handle 43 may be rotatably mounted on the channel 40, the shaft of the handle extending rotatably through the flange of the channel adjacent the gear 42 and said shaft being provided with a smaller gear 44 which meshes with gear 42, whereby rotation of the handle 43 causes the reel 41 to be rotated to wind up the cable 37 thereon.

In using the device of Figure 1, the outermost section 12 is first secured in a vertical position, the frame 19 is then secured to the outermost telescopic section 12, and the

clamps

30, 30 are engaged with the innermost section 16 to which the antenna is secured. The winch 38 is then operated to raise the inner section 16 to its extended position, in which position the section 16 may be locked to the next inner section 15 by means of a transverse bolt-46 engaged through the top portion of the section 15 and the lower portion of the section 16. This procedure is then repeated with the

clamp members

30, 30 engaged with the next inner section 15, The section 15 may be locked in its extended position by means of a transverse bolt 46 extending through the lower portion of section 15 and the upper-portion of section 14. The same procedure is then repeated to elevate the section 14. The operation is continued until the mast has been fully extended. To lower the tower, the procedure is reversed.

In using the form of the invention shown in Figures 2 and 3, the frame 19 carries the Winch 38, and the extension of the respective inner sections is accomplished by operating the winch 38 in the same manner as in the previously described embodiment of the invention except that the winch accompanies the frame 19.

As the sections increase in diameter, the effective aperture defined by the arcuate clamping plates 31 and 33 may be increased by changing the points of connection of the overlapped ends of the arcuate plates 31 and 33 in the manner above described, the openings 35 being provided for adjusting the size of the effective aperture defined by said clamping plates.

While certain specific embodiments of the invention have been disclosed in the foregoing description, it will be understood that various modifications within the spirit of the invention may occur to those skilled in the art. Therefore, it is intended that no limitations be placed on the invention except as defined by the scope of the appended claims;

What is claimed is:

1. In a tower scaffold, a tower comprising an outer section and an inner section having upper ends, the inner section being telescoped in the outer section, means on said upper end of the inner section engageable with the outer section to preclude subsidence of the upper end of the inner section below the upper end of the outer section, a frame surrounding and secured to the outer section, said frame having opposite ends, a holding post fixed to and rising above one end of the frame, a lifting post fixed to and rising from the other end of the frame, said posts having upper ends, a holding clamp, connecting means flexibly and dependingly securing the holding clamp to said holding post on a level above the upper end of the outer tower section, a sheave flexibly secured to the lifting post at the upper end of the lifting post, a cable trained over the sheave, said cable having a first end and a second end, a lifting clamp secured to the first end of the cable,

operating means engaged with the second end of the cable for operating the cable to relax said cable in one direction and to pull said cable in the opposite direction, said holding and lifting clamps each comprising plate means having apertures larger in diameter than and receiving the inner tower section, the lifting clamp engaging the inner tower section above the holding clamp.

2. In a tower scaffold, a tower comprising an outer section and an inner section having upper ends, the inner section being telescoped in the outer section, means on said upper end of the inner section engageable with the outer section to preclude subsidence of the upper end of the inner section below the upper end of the outer section, a frame surrounding andsecured to the outer section, said frame having opposite ends, a holding post fixed to and rising above one end of the frame, a lifting post fixed to and rising from the other end of the frame, said posts having upper ends, a holding clamp, connecting means flexibly and dependingly securing the holding clamp to said holding post on a level above the upper end of the outer tower section, a sheave flexibly secured to the lifting post at the upper end of the lifting post, a cable trained over the sheave, saidcable having a first end and a second end, a lifting clamp secured to the first end of the cable, operating means engaged with the second end of the cable for operating the cable to relax said cable in one direction and to pull said cable in the opposite direction, said holding and lifting clamps each comprising plate means having apertures larger in diameter than and receiving the inner tower section, the lifting clamp engaging the inner tower section above the holding clamp, the apertures in the plates defining opposed gripping edges engageable with opposite sides of the related tower sections when the plates are tilted relative to the axes of the tower sections, in line with the gripping edges, said connecting means being secured to the holding plate in line with the gripping edges thereof, and the cable being secured to the lifting plate inline with the gripping edges thereof.

References Cited in the file of this patent UNITED STATES vPATENTS Nelson Mar. 16,