US2763339A - Elevating tower - Google Patents

Description

Sept. 18, 1956 T. c. NORTH 2,763,339

ELEVATING TOWER Original EiledAJan. 20, 1950 5 Sheets-Sheen 1 j n INVENTo l Sept. 18, 1956 y T. C. NORTH ELEVATING TOWER original Filed Jan. 20, 195o 5 sheets-sheet 2 INVENTOR.

sept. 1s, 195e T. NORTH 2,763,339

ELEVATING TOWER Original Filed Jan. 20, 1950 A 5 Sheffcsfiihgmu 5 Sept. 18, 1956 T, C, NORTH 2,763,339

ELEVATING TOWER Original Filed Jan. 20, 1950 5 Sheets-Sheet 4 l: ig. 4.

INVENTOR. M M

T. C. NORTH ELEVATING TOWER Sept. 13, 1956 5 Sheets-Sheet 5 Original Filed Jan'. 20, 1950 IVENTOR. MMZQM United States Patent C ELEVATIN G TOWER Thomas C. North, Zelienople, Pa., assignor to Universal Manufacturing Corp., Zelienople, Pa., a corporation of Pennsylvania Grignal application January 20, 1950, Serial No. 139,623. Divided and this application October 19, 1955, Serial No. 541,327

3 Claims.V (Cl. 189-14) This invention relates to elevating towers in which a working platform is mounted on top of a vertical telescoping structure. This is a division of my abandoned copending patent application, Serial Number 139,693, tiled January 20, 1950. l

It is among the objects of this invention to provide a portable elevating tower which has tubular metal legs, which is strong but relatively light in weight, and which can readily be elevated and lowered.

In accordance with this invention, a plurality of telescoped vertical rectangular tower sections are supported in collapsed position by a portable base on which the outer section is rigidly mounted. The different sections have corner legs, with the legs of each section laterally overlapping the legs of the next smaller section at two opposite sides of the tower. Each leg is formed from a vertical tube circular in cross section secured to the inner narrow side of a vertical tube that is oblong in cross section with its sides parallel to the sides of the tower. Each circular tube projects laterally from the plane of the inner wide side of the adjoining oblong tube and substantially into engagement with the outer wide side of the adjacent oblong tube of the next smaller section. Guide rollers are supported by the legs of each section and engage the legs of the next smaller section on the other two opposite sides of the tower. Vertically spaced sheaves carried by two opposite sides ot each tower section have a cable extending around all of them in such a manner that when the effective length of the cable is shortened by reeling it in it will raise the different sections in succession. j

The elevated tower is steadied byoutrigging which preferably includes at each side of the base a vertical member rotatably connected to an adjacent side of the outer section of the tower, an Outrigger beam connected at one end to the lower end of the vertical member and adapted to be swung from a position from the side of the base outward to a position perpendicular to it, a diagonal brace pivotally connected at one end to the base and detachably connected at its opposite end to the outer end of the eX- tended beam, and a hook projecting from the inner end of the beam on the side opposite to the diagonal brace for receiving and supporting the free end of that brace when it is disconnected from the beam and the beam has been swung toward the pivoted end of the brace and against the base.

The preferred embodiment of the invention is illustrated in the accompanying drawings, in which:

Fig. 1 is a front view of the elevated tower with some of the central sections broken away;

Fig. 2 is a side View thereof; v

Fig. 3 is an enlarged fragmentary horizontal section taken on the line lll-lll of Fig. 1;

Fig. 4 is a horizontal section taken on the line IV-lV of Fig. 1, but with only half of the outrigging in operative position; j

Fig. 5 is an enlarged fragmentary vertical section taken on the line V--V of Fig. l and showing a safety support;

Fig. 6 is a front view of the safety support taken on the line VI-VI of Fig. 5; and

Fig. 7 is a fragmentary horizontal section taken on the level of line VII-VII of Fig. 5, but showing the legs at the side of the tower nearest to the observer.

Referring to the drawings, the base of the tower is formed from an elongated rectangular frame 1 supported at its corners by swivel wheels 2. Part or all of the frame may be covered with planks 3 to form a platform. Mounted on the base is a vertical rectangular tower section A that extends from one end of the base inward to about the center of the base and also entirely across the base frame. This section has four parallel corner legs 4 rigidly connected to the opposite sides of the base frame by vertical plates 5. The legs and side of the section nearest the center of the base will be referred to herein as the front legs and front side. The-front legs are connected by vertically spaced tubular rungs 7, to which a central vertical tube 8 is fastened. The back legs of this section are connected in the same manner. At the opposite sides of section A the front and rear legs are connected by upper and lower horizontal braces 9, by central horizontal braces 11 and by intermediate inclined braces 12. The entire section is braced by inclined rods 13 which extend from the opposite ends of the base up to the upper ends of the front legs.

To help prevent the tower from tipping over sideways, the base is provided with outrigging that can be folded against its opposite sides when not in use in order to conserve space. For this purpose, on both sides of the base the opposite ends of a vertical tube 16 are rotatably mounted in sleeves 17 and 18` secured to the upper portion of the adjacent front leg 4 and to the` base frame. The tube is prevented from sliding downward by means of a collar 19 rigidly mounted'on it and resting on vthe lower sleeve. Rigidly connected to `the tube below the lower sleeve is the inner end of a beam 21 that extends perpendicularly away from the base. The outer end of the beam carries a caster 22 Vthat rests on the ground. The 4outer end of the beam is connected to the upper end of the vertical tube 16 by an inclined brace 23.` To `hold the beam in its projecting operativel position, a diagonal brace 24 is detachably connected toits outer end. This is done by means of an upright pin 26 on the beam projecting up through a hole in the outer end of the brace. The inner end of the brace is pivotally connected at 27 to the frame of the base near the rear side of the tower. When it is desired to fold the outrigging against the tower, the diagonal braces 24 are disconnected from the beams 21 and swung outward. Then the beams are swung back toward the tower until theylie against the sides of the base, after which the diagonal braces are swung inward against the beams and held thereby` resting the` free ends of the braces on hooks 28 projecting from'the outer sides of the inner ends of the beams, as shown at the right hand side of Fig. 4. These hooks support the diagonal braces and keep them and the beamsfrom swinging out away from the base.

It is a feature'of this invention that the legs l4 of the lower section are tubular, each being formed from a vertical tube 4 circular in cross section welded to a narrow side of a four sided vertical tube 4" that is oblong in cross section. The oblong tubes have their wider sides parallel to the opposite side of the tower, and have their inner narrow sides welded to the round tubes. Also, the diameter of each round tube is greater than the thickness of the adjoining oblong tube. The outermost area of the round tube is disposedin the plane of the outer wide surface of the oblong tube, so.that the round tube will project inwardly from the plane of the inner wide side of the adjoining oblong tube. 4 l l Nesting inside of the outer section A of the tower that has just been described,'are several more telescope sections-B;*C, D, "Eg'F'and G that are constructed in substantially the same way as the outer section, except that the small sections do not require quite so much bracing asthe large ones. Sections D and E are not shown in the drawings sokthat the scale of the figures will not be too small. At thel two opposite sides of the tower the legsof each section laterally overlap the legs of the next smaller section to keep the different sections from moving sideways relative to one another. The overlapping is done by the round leg tubes which engage or practically engage the outer wide sides of the oblong leg tubes of `the next smaller section. The engagement is limited to'line contact so that there is but little friction between the legs when the sections are raised and lowered, compared with the severe friction that would exist if the flat surfaces of adjacent oblong tubes were allowed to rub against each other.

To keep the tower sections from moving forward or backward relative to one another and rubbing against one another, their legs are provided with guide rollers. Thus, brackets 29 are mounted on the inner wide side of each oblong leg tube, and a guide rollen 30 is rotatably mounted in each bracket and engages the outer narrow side of the leg of the next smaller tower section. That side of the leg being tlat,it forms an ideal track for the roller. Consequently, the tower sections roll against one another at their front and back as they are raised and lowered.

lAnother advantage of my particular tower legs is that by welding a circular tube to the narrow side of each oblong tube, the column strength of the legs is increased materially.

In order to make it possible to elevate the tower, each ofA its sections, except the inner one G, has sheaves 31 mounted between vertical plates 32 supported by the upper two 'rungs 7 at both the front and back of the section. Each section, except the inner and outer ones G and A, has a pair yof vertically spaced sheaves 33 and 34 mounted between vertical plates 36 supported by the lowest two rungs 7 atthe front of the section, and a like pair of sheaves at the back. The diameter of the upper sheave of each pair is smaller than the lower sheave. The inner section G has single sheaves 37 mounted between vertical plates 38 supported by its lowest pairs of rungs. Another pair of sheaves 39 are mounted on the base, one at the back and the other directly in front of the tower. h

Mounted on the front of the outer tower section A is a framework 41, in which a pair of drums 42 and 43 are journaled. The drums are turned by gears 44 which mesh with pinions 46 rigidly mounted on a shaft 47 that can be turned by a hand crank 48, so that both drums are turned simultaneously. As shown in Fig. 2, one end of a cable 49, shownin broken lines to avoid confusion with the solid lines, is connected to the upper drum 42 and extends up overvthe sheave 31 in the front of the outer section. From there it extends down around the lowest sheave 34 in the front of the second section B and up ,in front of the sheave 33 directly above it. The cable then extends up and around the sheave 31 in the upper end of the front of this same section and down around the lowest sheave 34 in the front of the third section C. The cable continues in the same manner -to pass around the sheaves in the front sides of the remaining sections until it passes under the sheave 37 in the front of the inner section G. From there the cable extends back across that tower section and up around the other sheave 37 in the back of it. ,It then extends up and around the sheave 31 in the upper end of the back of the next larger section F and down.' The cable is reeved around the sheaves in the back sides of the different tower sections in the same way as it is in the front, until it passes over the sheave 31 in the upper end of the .back side of the outer section A. `From there it extends..fdown and under the sheave 39 mounted on' the back of the base and then forward through the tower and up around the other base sheave 39 -to the lower drum 43. When the crank is turned the drums reel in both ends of the cable at the same time. Due to the way that the cable is reeved around the different sheaves, this shortening of its effective length causes the different sections to be raised in succession, starting with the smallest or inner section G.

The distance that each tower can rise out of the surrounding section is limited by stops. Thus, a stop 51 is welded to the outer side of each leg near its lower end. This stop projects beneath a similar stop 52 welded to the adjacent leg of the next larger tower section near its upper end. Stop 52 is spaced from the oblong leg beside it, so that they will not rub together. When the inner section G has been raised a predetermined distance, its stops 5l will strike the upper stops 52 of the surrounding section F and arrest any further relative movement between them. As the cable continues to be wound on the drums, section F must rise with section G until the lower stops of section F engage the upper stops of section E, whereupon section E begins to rise with sections F and G. This continues from section to section until the tower has reached the desired height or until the lower stops on section B strike the stops on section A. The drums then are locked to hold the tower in extended or elevated position as shown in Figs. l and 2.

Another feature of this invention is that in case the cable breaks or a sheave pulls loose, each tower section can only drop a short distance, further falling being prevented by safety supports. As best shown in Figs. 5, 6 and 7, each of these supports is a reinforced angle member 55 having a vertical portion that normally engages an angle 56 welded on the next to the top rung 7 of a tower section, and a horizontal portion that projects between the legs of the next smaller section. Where these two portions of the angle member join it is welded to a sleeve 57 that is journaled on a pivot pin 58 which extends through a pair of vertical plates 59 connected to the upper pair of rungs. Preferably, there are two safety supports lat the front of each section and two more at the back. It will be seen that when the tower sections are raised, the rising rungs will swing the safety supports upward and thus pass by them as indicated in broken lines in Fig. 5. As each rung passes a safety support the latter drops back into operative position below it, so that in case a tower section drops, it will be arrested by two of its rungs striking the four safety supports mounted on the surrounding section. Before the sections can be lowered into one another to collapse the tower, the safety supports 55 must be raised out of the path of the rungs. To accomplish this a workman swings each safety support up behind a hook 61 which is pivotally mounted on a pin 62 extending through the vertical plates 59 above the safety support.

Mounted on top of the uppermost section G of the tower is a working platform 65 provided with a trap door 66 through which a workman may climb from the rungs 7 below. The platform is surrounded by a removable guard rail 67.

According to the provisions of the patent statutes, I have explained the principle of my invention and have illustrated and described what I now consider to represent its best embodiment. However, I desire to have it understood that, within the scope of the appended claims, the invention may be practiced otherwise than as specifically illustrated and described.

I claim:

l. An elevating tower comprising a base, a plurality of telescoped vertical rectangular tower sections supported by the base with the outer section rigidly mounted thereon, said sections having corner legs, the legs of each tower section laterally overlapping the legs of the next smaller section at two opposite sides of the tower, each .5 leg being formed from a vertical tube circular in cross section secured to the inner narrow side of a vertical tube that is oblong in cross section with its sides parallel to the sides of the tower, each circular tube projecting laterally from the plane of the inner wide side of the adjoining oblong tube and substantially into engagement with the outer wide side of the adjacent oblong tube of the next smaller section, a guide roller supported from said inner wide side of each oblong tube and engaging the outer narrow side of the adjacent oblong tube of the next smaller section, and means for raising and lowering the tower sections to extend and retract the tower.

2. An elevating tower according to claim 1, including upper stop members mounted on said circular tubes near their upper ends and projecting part way across the outer wide side of the adjacent oblong tube of the next smaller section in spaced relation thereto, and lower stop members mounted on said outer wide sides near their lower ends beneath said upper stop members on the next larger section, whereby the lower stop members on each section will engage the upper stop members on the next larger section when the tower sections are raised.

3. An elevating tower comprising a base, a plurality of telescoped vertical rectangular tower sections supported by the base with the outer section rigidly mounted thereon, said sections having corner legs, the legs of each tower section laterally overlapping the legs of the next smaller section at two opposite sides of the tower, each leg being formed from a vertical tube circular in cross section secured to the inner side of a vertical tube that is rectangular in cross section with its sides parallel to the sides of the tower, each circular tube projecting laterally from the plane of one side of the adjoining rectangular tube and substantially into engagement with one side of the adjacent rectangular tube of the next smaller section, a guide roller supported from said one side of said adjoining rectangular tube and substantially References Cited in the le of this patent UNITED STATES PATENTS Dye Mar. 11, 1884 Teal June 24, 1884

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