US3021885A - Apparatus for assembling cross-braces on a multi-leg tower - Google Patents

Description

Feb. 20, 1962 1. D. ROHN 3,021,

APPARATUS FOR ASSEMBLING CROSSBRACES ON A MULTI-LEG TOWER Filed July 26, 1955 4 Sheets-Sheet 1 LYVEI? fur Feb. 20, 1962 1. D. ROHN 3,021,885

APPARATUS FOR ASSEMBLING CROSS-BRACES ON A MULTI-LEG TOWER Filed July 26, 1955 4 Sheets-Sheet 2 Feb. 20, 1962 1. D. ROHN 3,021,885

APPARATUS FOR ASSEMBLING CROSS-BRACES ON A MULTI-LEG TOWER Filed July 26, 1955 4 Sheets-Sheet 3 41 Feb. 20, 1962 1. D. ROHN 3,02

-LEG TOWER 4 Sheets-Sheet 4 APPARATUS FOR ASSEMBLING CROSS-BRACES ON A MULTI Filed July 26, 1955 .21? F227 Tar IVAN .pw/a'H r Far/1v 3,021,885 APPARATUS FGR ASSEMBLEIG CROSS-BRACES H ON A MULTI-LEG TOWER Ivan Dwight Rohn', 116 LimestoneBellevue, Peoria; Ill. Filed any 26, 1955, Ser. No. 524,345 9 Claims. (11. 153-1) This invention relates to an apparatus for assembling cross-braces on a multi-leg tower or the like;

At the present time there is a huge demand for various types of towers and more particularly light weight towers for use by televion and radio owners" in areas where good reception requires an elevated aerial. Due to the" fact that different areas require different heights for the tower, in order to attain good reception and for reasons of ease of assembly, it is contemplated that the tower be Composed of a plurality of reinforced light weight sections.

It is therefore an object of the present invention to provide a novel apparatus for forming and assembling cross-braces on a multi-leg sectioned tower capable of meeting the demands of the public for a stu'r'dv light weight tower.

Another object of this invention is to provide a never apparatus for forming and assembling cross-braces on a multi-leg tower which permits large scale production techniques to be utilized at the lowest possible cost.

another object of the present invention is to provide novel apparatus to facilitate the formation of and assembling of cross-braces on a multi-leg sectioned tower.

Other objects, features and advantages of the present invention will be more readily apparent from the following detailed description of the drawings illustrating a single embodiment thereof, in which:

FIGURE 1 is a front eievational view of the apparatus utilized in the assembly of the cross-braces on the tower; FIGURE 2 is a fragmentary cross sectional view taken on the line Ii -II of FIGURE 1 showing the straps or blanks in place and one upright laying across same to be clenched thereto;

FlGURE 3 is a side elevational view showing in full and dotted lines how the cross-brace is attached to the reg or upright;

FZGURE 4 is a fragmentary side elevational view similar to FIGURE 3 showing a subsequent step' in my invenuon;

FIGURE 5 is an enlarged fragmentary sectional view through FIGURE 3 showing in greater detail how the strap blank is attached to the upright;

FIGURE 6 is an enlarged fragmentary sectional view similm to FIGURE 5 only showing a subsequent step of my mvention;

FIGURE 7 is a fragmentary front view showing the formed tower with apparatus thereon to facilitate the welding operation;

FIGURE 8 is an enlarged fragmentary view of the clamp and end jig shown in FIGURE 7;

FIGURE 9 is enlarged cross sectional view taken substantially on the line IXIX of FIGURE 8 looking in the direction indicated by the arrows; v

FIGURE 10 is an enlarged fragmentary perspective view showing a portion of the completed tower;

FIGURE ll is an enlarged fragmentary cross sectional view taken on the line XI-XI of FIGURE 3 looking in the direction or" the arrows; I

FIGURE 12 is an enlarged elevational view of a strut or brace blank; and 7 FIGURE 13 is an enlarged cross sectional view taken substantially on the line XIII-XIII of FIGURE 12 looking in the direction indicated by the arrows.

As shown on the drawings:

. H. '.V i- The reference numeral to (FIG. 3) 1nd1cates generally an anchored press or break machine which is upastsss Faltented Feb. 20, 1962 2 erated by a motor 11 connected to a V-belt drive 12 for driving an eccentric 13. Connected to the eccentric 13 are twove'rtical moving rams Hand 15 (FIG. 1) which are joined at their lower vertical ends by means of a pivotal connection (FIG. 1) to a hold-down member 16. The hold-down member is movable vertically relative to the press 10 and is guided in its; vertical movement by means of a dovetail connection Illa (FIG. 11) between the hold-down member 1 6 and press 10'. Ailixed on the vertically underside of the hold down member is are suitably eight spaced vertically movable plungers 17.

Joined to the press 10 just below the plungers 17 are a plurality of sets or pairs of spaced generally horizontaly extending fixedly mounted arms or members 13 and 19 (FIG. 7) which are all identical: in construction. The arms'lsan'd 19 are bridged between and fixedly connected to the frame 1'0 and vertically extending space d anchor supports 20 and 21'. The supports 26 and 21 and the frame 10 are engaged with opposite ends of the pairs of arms 18 and 19 and serve to maintain the arms in a stationary position.

Pivots 22 are provided between each of the pairs of the arms 18' and 19 and lever arm or member 23 enabling the lever arm to be rocked on the pivots 22 when one end of the lever arm is engaged and actuated by the plunger 17 or actuator. Each of the arms 23 is provided with a die a U-shaped die or a clinching die structure or a strap and rod supporting and strap clenching die area which is indicated generally at 24 and is disposed generally on the outer side of the arm 23.

It' will be best seen in FIGURES 1 and 3 that aplurality of spaced'pivotally mounted arms 23 are illustrated which together with the other apparatus define eight separate stations, each of which is capable of receiving a cross brace blank 25 (FIGS; 12 and 13) which is to be formed in' the die 24 inthe assembly of same upon the tower indicated generally at 26 in FIGURE 10. The tower is preferably of a tripodal construction having spaced tubular legs 27. More than three legs 27 may be used, if desired, but a tripodal type tower is the least expensive to manufacture.

The cross brace blanks 25 are each of a reinforced more or less M-shaped transverse cross section (FIG. 13) having at spaced intervals of the blank along the length flat portions 28 (FIGS. 5 and 12) which are to be deformed to engage nestingly about the rods 27 ashoreinafter will become more apparent. The number of these fiat portions 2Sdepend of course upon the number of legs 27 in the tower 26; If a tower having three legs is to be manufactured then two flat portions 28' are employed to engage two of the legs 27 and the ends 25:: and 25b of the blanks 25 are engaged with and secured to the third leg 27 as shall become more evident hereinafter. I

Each of the dies 24 (FIGS. 5 and 6) on the lever arms 23 includes a recess 2? having a vertically slidable spring tensioned anvil 30 adjustably mounted therein. The lower eridof the re'cess'29 leads into a slot 31 which is adapted to receive a bolt 32 having a spring 33 therea round in the recess; The bolt 31 is attached to a nut atone end with the other end bearing against the anvil for adjusting the level of the anvil with the top surface of the arm 23 whereby the brace or strap blank 25 may be maintained in engagement-against the tubing 27 during the clenching operation;

Mounted on the arm 23 on opposite sides of the recess 29 are protuberances 35 and 36 which serve to aid in centering a flat portion 28 of the brace or strut relative to the die (FIGS. 5 and 6). By so doing; the uprights may be equidistantly spaced from one another since the fiat portio'ns' 28' on" the blanks 25 are evenly spaced.

The amuse-harasarcuate' indentation or a die bottom- $7 which is a" component of the die 24;" and aids in the forming and assembly of the brace blanks 25 on the rods 27. In addition, spaced corners or strap forming or bending edges 33 and 3? at the vertically upper end of the recess 29 define edges along with the vertical side walls for further aiding in the formation and assembly of the braces on the rods (FIGS. 5 and 6). The stationary arms 19 have notched ends or areas or channeled rod gripping areas 40 closely approximating the cross sectional configuration of the rods 27.

in the formation of the tower section the arms 18 and 19 function as one leg of a scissor structure with the lever arms 23 being movable relative to the stationary arms 18 and 19 by the operation of the actuator structure which includes the press as well as the hold down member 16 and the plunger 17. The actuator structure provides means on the apparatus to cause relative movement between the scissor first and second legs to clench the straps to the rod or upright. When the second leg of the scissor structure is actuated the upright is forced against the one leg of the scissor structure the straps are caused to be bent and deformed about the upright by means of the dies 24 which are spaced along the second leg of the scissor structure.

Method of operation The first step in the operation of my novel apparatus is to insert the cross-brace blanks 25, in this case eight of them, although any suitable number may be employed, upon the horizontally spaced receiving stations of the machine. The fiat or corner portion 24 of each blank is centered with relation to the protuberances 35 and 36 at each station so that the portion 24 is vertically aligned with the die recess 29 (FIG. 3).

Thereafter a rod is transversely positioned across all eight of the support strap blanks 25 and in each instance is rested upon a flat portion 29 of each blank. It will be noted that a centering jig 41 (FIGS. 1 and 2) is secured to the press and carried at one end of the row of stations by one of the arms 18 so as to center the rod 27 relative to the supported blanks 25. The jig 41 has three stops 42 against which each of the tubular ends of the rods 27 are adapted to bear against in the progressive assembly of the three legs 27 and the strap blanks thereby insuring proper alignment of the ends of the legs.

At this point the anvil 30 may be adjusted to keep the brace blank 25 firmly tensioned against the tubing 27 during the clenching operation (FIG. 6).

The next step is to start the machine with the plungers 17 urging one end of each of the lever arms 23 downward and thereby urging the other end of the arm having the die 24 vertically upward to forcibly press the leg 27 against the notched area 46 of the stationary arm 19. As a consequence of the leg or rod 27 striking the arms 18 and 19, the force of the impact causes the flat portion 28 to be nested or clenched more than half way around the rod to firmly grip and clench same (FIG. 6). It will be appreciated the preferred manner of operation is one where the clenching action occurs simultaneously at all of the stations.

The operator of the machine then picks up the rod 27 and attached brace blanks 25 and manually rotates or indexes the assembly (FIG. 4) by sliding same rearwardly toward the press so that the next set of flat portions 28 of the strap blanks are aligned with the dies 24. A second rod or upright is transversely aligned by means of jig 4-1 and disposed over the dies 24 so that it rests on the flat portions of the straps 25. The plungers 17 are again activated to clench the second rod to the brace blanks 25 in the same manner as previously.

The operator then indexes or rotates the assembly again. The free ends 25a and 2512 (FIG. 9) of each of the braces 25 are then aligned end to end and the third rod is properly positioned with respect to the other'rods already clenched to the braces by means of the jig 41.

Again the plungers 17 are activated and the end portions 25a and 2512 are deformed so as to nest about the rod.

In order to insure more reinforced connections between the rods and the formed cross braces 43, each of the formed braces 43 where engaged with the rods 27 may be welded to the rods. To aid in this operation jigs 44 and 45 (FIG. 8) are utilized. Jig 44 (FIG. 8) comprises a main tripodal base 46 provided with three tubular extensions 47 each having a female terminal 43. Since the rods 27 have male terminals 49 with reduced diameters to facilitate in the vertical stacking of same, they may be readily inserted into the female terminals 48 and maintained in aligned position by means of a pin 58 through the male and female terminals.

Jig 45 comprises a bar 51 having spaced clip like clamps 52 at intervals thereon. These spaced clamps 52 are each engaged over the free ends 25a and 25b to hold same in tight engagement with the rod 27 (FIGURES 7-9).

The final step in my novel method is to weld or otherwise secure each of the points of contact between the rods 27 and the nested portions of the cross braces 43. Any suitable welding equipment may be used to weld the assembled tower braces and legs while they are held in the jigs 44 and 45 above described. Thereafter these jigs are removed from the completed tower section.

It will be understood that variations and modifications may be efiected without departing from the novel concepts of the present invention.

I claim as my invention:

1. In an apparatus to form and attach a plurality of longitudinally'spaced connecting straps to spaced uprights to form a tower section, strap receiving stations each having a pivotal connection joining it with the apparatus, the strap receiving stations being adapted to support connecting straps and an upright disposed on the connecting straps in transverse relation, each of said strap receiving stations having a die capable of receiving a portion of a connecting strap and a portion of an upright, a fixed arm mounted in a fixed position on said apparatus adjacent said die for engaging said uprights, the dies being pivotally movable in an arc towards and away from said fixed arms, means on said apparatus engaged against said strap receiving stations to rotate the dies in an arc towards said fixed arms with said fixed arms being engageable against an upright and cooperating with said dies to deform a strap portion of each of the straps by causing the upright and the strap portions to be worked in the dies and to cause the strap portions to be contemporaneously clenched in assembly with the upright, each of said dies having a vertically movable die bottom for engagement with a connecting strap and spaced strap bending edges with said die bottom disposed between them, and means connected to the die bottom for controlling the position of said die bottom with respect to said spaced strap bending edges when said straps and rods are being loaded on said stations.

2. In an apparatus to form and attach a plurality of longitudinally spaced connecting straps to spaced uprights to form a tower section, strap receiving stations each having a pivotal connection joining it with the apparatus, the strap receiving stations being adapted to support connecting straps and an upright disposed on the connecting straps in transverse relation, each of said strap receiving stations having a die capable of receiving a portion of a connecting strap and a portion of an upright, a fixed arm mounted in a fixed position on said apparatus adjacent said die for engaging said uprights, the dies being pivotally movable in an arc towards and away from said fixed arms, means on said apparatus engaged against said strap receiving stations to rotate the dies in an arc towards said fixed arms with said fixed arms being engageable against an upright and cooperating with said dies to deform a strap portion of each of the straps by causing the upright and the strap portions to be worked in the dies and to cause the strap portions to be contemporaneously clenched in assembly with the upright, each of said dies having a vertically movable die bottom for engagement with a connecting strap and spaced strap bending edges with said die bottom disposed between them, and means connected to the die bottom and cooperable with said fixed arms toinsure that the strap portions being deformed are maintained in abutment with the upright during the clenching operation.

3. In a tower section forming apparatus for attaching a plurality of longitudinally spaced connecting straps to spaced uprights, a press, a series of strap receiving stations each comprising a pair of spaced fixed arms and a rocking arm mounted between and pivoted on said fixed arms between its opposite ends, and a strap bending die disposed on said rocking arm at each station, the press being connected to the rocking arms for contemporaneously causing said rocking arms at each station to rock to cause the straps to be wrapped around the upright by means of said dies.

4. In a tower section forming apparatus for attaching a plurality of longitudinally spaced connecting straps to spaced uprights, a press, a series of strap receiving stations each comprising a pair of spaced fixed arms and a rocking arm mounted between and pivoted on said fixed arms between its opposite ends, and a strap bending die disposed on said rocking arm at each station, the press being connected to the rocking arms for contemporaneously causing said rocking arms at each station to rock to cause the straps to be wrapped around the upright by means of said dies, said press including a series of vertically movable rams each engaged with a rearward end of one of said rocking arms for rocking said rocking arm on its pivot.

5. In a tower section forming apparatus for attaching a plurality of longitudinally spaced connecting straps to spaced uprights, a press, a series or" strap receiving stations each comprising a pair of spaced fixed arms and a rocking arm mounted between and pivoted on said fixed arms between its opposite ends, and a strap bending die disposed on said rocking arm at each station, the press being connected to the rocking arms for contemporaneously causing said rocking arms at each station to rock to cause the straps to be wrapped around the upright by means of said dies, each of said dies having a vertically movable die bottom for engagement with a connecting strap and spaced strap bending edges with said die bottom disposed between them, and means connected to the die bottom and cooperable with said fixed arms to insure that the strap portions being deformed are maintained in abutment with the upright during the clenching operation.

6. In a tower section forming apparatus for attaching a plurality of longitudinally spaced connecting straps to spaced uprights, a press, a series of strap receiving tations each comprising a pair of spaced fixed arms and a rocking arm pivoted on said apparatus at each of said stations and disposed between said fixed arms, and a strap bending die disposed on said rocking arm at each station, the press being connected to the rocking arms for contemporaneously causing said rocking arms at each station to rock to cause the straps to be wrapped around the upright by means of said dies. 1

7. In a tower section forming apparatus for attaching a plurality of longitudinally spaced connecting straps to spaced uprights, a press, a series of strap receiving stations each comprising a fixed arm and a rocking arm mounted alongside of said fixed arm and pivoted between its opposite ends on the apparatus at each of said stations, and a strap bending die disposed on said rocking arm at each station, the press being connected to the rocking arms for contemporaneously causing said rocking arm at each station to rock to cause the straps to be wrapped around the upright by means of said dies, said press being positioned rearwardly of said dies and connected with rearward ends or" said rocking arms leaving an area above the dies open for free movement of collapsed strap portions therein.

8. In an apparatus to form and attach a plurality of longitudinally spaced transverse connecting straps to spaced uprights to form a tower section, a press having vertically movable rams, spaced pivotally mounted members mounted on the apparatus and disposed in front of said vertically movable rams and being capable of receiving the straps thereon at spaced intervals and capable of supporting an upright transverse of the straps, a die on a forward end of each of said members, said dies being located for wardly of said vertically movable rams, a fixed arm disposed adjacent each of said dies, said fixed arms being adapted for engagement with the upright, said vertically movable rams being engageable with rear ends of said pivotally mounted members to move said dies towards said fixed arms to forcibly urge an upright and straps towards one another with the fixed arms being engageable against the upright to bend intermediate portions of straps in the dies and to form intermediate strap portions about an upright in clenched engagement therewith.

9. In a tower section forming apparatus for attaching a plurality of longitudinally spaced connecting straps to spaced uprights, a series of longitudinally spaced strap receiving stations each having a die, said strap receiving stations comprising means for collapsing and upsetting longitudinally spaced portions of the connecting straps about an upright, a press disposed at a rear side of said dies leaving a forward area located forwardly of said dies free for an operator, and leaving an area about the dies free of the press for free movement of collapsed portions of each strap therein, said means including relatively movable arms positioned alongside one another at each station and which arms are pivoted with respect to one another and have vertically spaced portions for engagement with an underneath side of each strap and a top side of the upright and with all of the said arms being disposed between said press and said station, at least one of said arms at each station being connected with the press at a rearward location disposed rearwardly of said dies and actuatable on its pivot by the press at said rearward location for simultaneously causing spaced straps to be upset around an upright by means of said dies.

References Cited in the file of this patent UNITED STATES PATENTS 209,747 Belt Nov. 12, 1878 309,801 Rayner Dec. 23, 1884 760,167 Warner May 17, 1904 788,969 Walker May 2, 1905 841,326 Knutsen Jan. 15, 1907 969,859 Haskell Sept. 13, 1910 1,675,188 Macomber June 26, 1928 1,692,033 Gray Nov. 20, 1928 1,720,133 Le Roy July 9, 1929 1,776,124 Krutt Sept. 16, 1930 1,911,624 Kuklenski May 30, 1933 1,954,545 Uline Apr. 10, 1934 1,981,189 Peterson Nov. 20, 1934 1,981,221 Chesley Nov. 20, 1934 1,994,428 Keil Mar. 12, 1935 2,253,639 McMahan Aug. 26, 1941 2,281,299 Steenstrup Apr. 28, 1942 2,376,604 Lathrop May 22, 1945 2,399,053 McLaren Apr. 23, 1946 2,596,375 Daniels May 13, 1952 2,601,029 King June 17, 1952 2,846,760 Rohn Aug. 12, 1958

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