US3485321A

US3485321A - Work tower

Info

Publication number: US3485321A
Application number: US691668A
Authority: US
Inventors: Raymond E Smith Jr
Original assignee: SMITH RAYMOND E JUN
Current assignee: SMITH RAYMOND E JUN
Priority date: 1967-11-20
Filing date: 1967-11-20
Publication date: 1969-12-23
Anticipated expiration: 1986-12-23

Description

Dec. 23, 1969 R. E. SMITH, JR

WORK TOWER 16 Sheets-Sheet 1 Filed Nov. 20. 196'? Dec. 23, 1969 RYE. sum-l, JR 3,485,321

WORK TOWER Filed Nov. 20, 1967 16 Sheets-Sheet 2 jjj/a@ ZZ fl .5

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Dec. 23, 1969 Filed Nov. 26, 1957 R. E. SMITH, .m 3,485,321

- WORK TOWER 16 Sheets-Sheet 3 Dec. 23, 1969 R. E. SMITH, .1R 3,485,321

WORK TOWER Filed Nov. 20, 1967 16 Sheets-Sheet 4 ji@ 5 .25, Q f

^ fz iV Dec. 23, 1969 "hjEsMm-k JR 3,485,321

WORK TOWER Filed Nov. 20, 1967 16 Sheets-Sheet 5 11g 7 L .D7 I

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WORK TOWER Filed NOV. 20, 1967 16 Sheets-Sheet 6 El] Y IV [El {El} 242 .g l ,y

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Dec. 23, 1969 WORK TOWER 16 Sheets-Sheet 7 Filed NOV. 20, 1967 Dec. 23, 1969 R. E. 5mm, JR

WORK TOWER 16 Sheets-Sheet 8 Filed NOV. 20, 1967 16 Sheets-Sheet 9 WORK TOWER R. E. SMITH, JR

Dec. 23, 1969 Filed Nov. 20, 1967 Dec. 23, 1969 R. E. SMITH, 1R 3,485,321

WORK TOWER Filed Nov. 20, 1967 16 Sheets-Sheet 1o Dec. 23, 1969 R. E. SMITH, JR

WORK TOWER 16 Sheets-Sheet 11 Filed Nov. 20, 1967 Dec. 23, 1969 R. E. SMITH, JR

WORK TOWER 16 Sheets-Sheet x2 Filed NOV. 20. 1967 INM,

Dec. 2s, 1969 R. E. SM'IT'H, JR 3,485,321

WORK TOWER Filed NOV. 20, 1967 16 Sheets-Sheet 125 Dec. 23, 1969 yR. E. SMITH, .1R

WORK TOWER 16 Sheets-Sheet 14 Filed Nov. 20, 1967 Dec. 23, 1969 R. E. Mlm JR 3,485,321

WORK TOWER Filed Nov. 2o, 1967 1e sheets-sheet 15 Dec. 23, 1969 R. E. SMITH, JR 3,485,321

WORK TOWER Filed Nov. 20, 1967 f 16 Sheets-Sheet 1e 3,485,321 WURK TOWER Raymond E. Smith, Ir., 385 E. Greenwood Ave., Lake Forest, Ill. 60045 Filed Novu 20, 1967, Ser. No. 691,668 Int. Cl. Elllg N; E06c 5/04;F16g 11/12 US. Cl. 182-131 14 Claims ABSTRACT 0F THE DISCLOSUREA A work tower with a hydraulically positionable personnel platform and Work lplatform and hydraulically powered outriggers which are vertically and horizontally positionable to tilt and support the work tower at a vertical angle.

Introduction The present invention relates lto work towers and more specifically to a fully portable work tower which provides exible operation with integral powered loading, unloading and erection in a highly compact structure adapted for maneuverability in limited space.

The invention basically comprises a movable base supporting a personnel-supporting platform, means for raising and lowering the platform, and Outrigger means pivotally connected to the base. The Outrigger means are extendable and are adapted to selectively vertically tilt the work tower for transportation.

Further objects, features and advantages of the invention pertain to the particular arrangement and structure whereby the above mentioned aspects of the invention are attained. The invention will be better understood by reference to the following description and to the drawings forming a part thereof, which are substantially to scale, wherein:

FIGURE 1 is a top plan elevation of an exemplary work tower in accordance with the present invention with outriggers extended;

FIGURE 2 is a sectional view taken along the line 2 2 of FIGURE 1;

FIGURE 3 is a front elevation taken along the line 3 3 of FIGURE l; v

FIGURE 4 is a side elevation taken along 4 4 of FIGURE l;

FIGURE 5 is an enlarged 5 5 of FIGURE 3;

FIGURE 6 is a sectional view taken along 6 6 of FIGURE 5;

FIGURE 7 is an enlarged view taken along the line 7 7 of FIGURE 3;

FIGURE 8 is a plan view showing the Work tower moving on end through a narrow doorway;

FIGURE 9 is a side elevation of the work tower in its collapsed position taken along theV line 9 9 of FIG- URE 3;

FIGURE l0 is a enlarged side elevation of the lower position of FIGURE 9 with the work tower rotated 90 to a vertical position;

FIGURE 11 is a top plan view of the work tower in a vertical position looking in the direction of the line 11 11 of FIGURE l0;

FIGURE 12 is a bottom elevation of the lower portion of the work tower taken along the line 12-12 of FIGURE 1l;

FIGURE 13 is a front elevation of the work tower taken along the line 13 13 of FIGURE 9;

FIGURE 14 is a plan elevation taken along the line 14-14 of FIGURE 9;

FIGURE 15 is a sectional view taken along the line 1-5-15 of FIGURE 14;

the line view taken along the line the line nited States Patent() "ice FIGURE 16 is a sectional view taken along 16-16 of FIGURE 9;

FIGURE 17 is a sectional view taken along 17 17 of FIGURE 9;

FIGURE 18 is a sectional view taken along 18-18 of FIGURE 9;

FIGURE 19 is a perspective view of the frame of an Outrigger ofthe work tower;

FIGURE 20 is an enlarged fragmentary view taken along the line 20 20 of FIGURE 13;

FIGURE 21 is a sectional view taken along the line 21 21 of FIGURE 20;

FIGURE 22 is a fragmentary sectional view taken along the line 22 22 of FIGURE 2l;

FIGURE 23 is a view similar to FIGURE 20 but with the Outrigger rotated 45 FIGURES 24 through 29 are schematic side elevations successively illustrating the loading of the work tower of FIGURES l through 23 onto a transport vehicle;

And FIGURES 30 through 32 are side elevations of the work tower of FIGURES 1 through 29 in a vertical position.

the line the line the line Description of the exemplary embodiment Referring to the FIGURES 1 through 32, there is shown an exemplary work tower 20 in accordance with the present invention. The work tower 20 is a self-contained portable unit including a wheeled base 22 and a personnel-supporting platform 24 raised and lowered from the base 22 by a rst hydraulically powered scissors linkage 26. The personnel platform 24 mounts a separate work supporting platform 28 independently raised and lowered by a second hydraulically powered scissors linkage 30. Pivotally connected to the base 22 at opposite sides are

outriggers

32 and 34 adapted to extend from the base. The

outriggers

32 and 34 are vertically pivotable by integral hydraulic cylinders with respect to the base 22 to selectively vertically tilt the entire work tower 20 to any desired angle including a fully vertical position.

The entire work tower 20 is preferably actuated by hydraulic cylinders powered by a hydraulic system on the base 22. Commercially available hydraulic system components may be employed. Line current or self-contained batteries may be employed to drive the hydraulic pump.

Considering the base 22, it provides the basic connection point and support for the work tower 20. Preferably, it has two large iixed axis wheels 36 at a first end 3S and two large pivotable (castered) wheels at the opposite or second end 40.

Each of the two

outriggers

32 or 34 is adapted to act as an arm for hydraulically manuevering the entire work tower 20. The entire Outrigger unit is pivotally connected by its frame 41, shown in FIGURE 19, to the base 22 by a vertical pin 42. The Outrigger is normally restrained from horizontal rotation by a securing pin 44 connecting an ear of the Outrigger frame 41 with the base 22. As shown in FIGURE 23, two different apertures for the pin 44 may be provided. Thus, the Outrigger may be held parallel the side of the base 22 or horizontally pivoted to a 45 angle to the base 22 to provide lateral stability forrthe work tower as shown in FIGURE l. In either position, with the pin 44 in place the Outrigger is secured to the base 22.

The outriggers each include an elongate Outrigger arm 46 pivotally secured thereto for horizontal rotation about a pin 4S in the frame 41 adjacent the inner end of the Outrigger arm 46. The arm 46 is a rectangular tubular member and is adapted to slidably receive therein an extension arm 50. The extension arm 50 slides into either the inner or outer ends of the Outrigger arm 46, co-

3 linearly extending the Outrigger beyond the end of the work tower in the first case and past the midpoint or center of gravity of the work tower in the other case. The extension arm 50 can also telescope almost entirely inside the Outrigger arm 46 for minimum extension as shown in FIGURES 30 through 32.

The Outrigger contains its own wheel system comprising a small caster wheel at the outer end of the Outrigger arm 46 and a small caster wheel 51 at the outer end of the extension arm. The extension arm 50 also has a pin lockable fixed axis wheel 52 Opposite its caster wheel 51. By inserting the extension arm 50 in the Outrigger arm upside down, the wheel 52 is presented toward the oor rather than the caster wheel 51. It will be noted that, with the Outrigger arm in a horizontal position and the work tower in its normal position, as in FIGURE 24, only the wheels on the base 22 contact the floor. The wheels on the base 22 extend below the wheels on the Outrigger arms and the extension arm, thereby providing clearance for positioning the outriggers.

The Outrigger may be tilted vertically, i.e. about a horizontal axis, or the base may be tilted vertically depending upon the position of the extension arm 50. This vertical movement may be either above or below the horizontal and is accomplished by the piston movement of a hydraulic cylinder 54. The selectable operation of the cylinder 54 provides in effect a variable length arm connecting the outer end of the Outrigger arm 46 with a pivot point 56 on the Outrigger frame 41 spaced above the piston 48. Thus expansion or contraction of the cylinder 54 respectively lowers or raises the outer end of the Outrigger arm 46, thereby pivoting both the Outrigger arm and the extension arm vertically about the pin 48.

When the work tower is tilted into its vertical or on end position by the

outriggers

32 and 34, as in FIGURES 8 and 10 through 12, the work tower is supported and movable on the Outrigger wheels alone. The wheels on the base 22 are pivoted off the floor. Accordingly, referring to FIGURES through 32, to allow the retraction of the extension arm 50, an elongated lever 58 is provided to lift both the first end 38 of the base and the outriggers slightly above the floor. The lever 58 has its fulcrum point on the base 22 closely spaced above the floor to provide a high leverage ratio. The short arm of the lever below the fulcrum is adapted to engage the floor and to tilt up and hold the work tower and the outriggers when the lever 58 is rotated from a generally vertical to a generally horizontal position.

The personnel-supporting platform 24 may be automatically from a compact folded position to any selected working height with the personnel remaining on the work tower. Referring particulary to FIGURES 4 and 7, an effective yet simple hydraulically powered scissors linkage 26 raises and lowers the platform 24 from the base 22 while maintaining the horizontal level of the platform. The scissors linkage 26 includes at both sides of the work tower 20 two

elongate legs

60 and 62 centrally pivotally connected. The lower end of the leg 60 is pin connected to the first end 38 of the base 22. The corresponding overlying end of the platform 24 is pin connected to the upper end of the leg 62. The upper end of the leg 60 has a roller which engages and rolls horizontally along the underside of the platform 24. Correspondingly, a roller on the lower end of the leg 62 rollably engages the base 22.

The lifting of the platform 24 is provided here by a hydraulic cylinder 64. Because of the large forces and varying positions involved, a special lever link 66 connection is preferably provided between the hydraulic cylinder 64 and the scissors linkage 26. The cylinder 64 is pivotally secured at one end to the lower end of the leg 60. The piston end of the cylinder 64 is pivotally secured to the Outer end of the link 66. The link 66 is an elongate integral member and is pivotally secured to the lower portion of the leg 62 at a pivot point 68. Due

to the pivotal connections, the cylinder 64 and the link 66 are normally pulled colinearly by the cylinder 64. and the lifting force exerted by lthe cylinder 64 normally acts through the pivot point 68.

However, for the initial lifting movement of the work platform, i.e. when the scissors 26 are closed, a desired different lifting leverage is provided. This is provided by a fulcrum projection 70 on the link 66. The projection 70 extends at right angles to the link 66 substantially spaced from the pivot point 68. When the scissors 26 are substantially closed, as in FIGURES 9 and 15, the projection 70 operatively engages a point of contact 72 on the leg 62 spaced substantially above the pivot point 68. It may be seen that in this position, the link 66 is not colinear the cylinder 64. ILower pressure is needed in the cylinder 64 for the initial lifting of the platform 24 than would be required without this arrangement.

The work supporting platform 28 may be independently raised and lowered above the personnel-supporting platform 24 to place the work materials at any desired height convenient to the workmen and the ceiling or work height, thus greatly improving working efficiency in many applications. The work platform 28 is positioned and supported by a separate hydraulic powered scissors linkage 30 connected to and overlying the personnel platform 24 as shown in FIGURES 4 through 6. It differs somewhat from the personnel platform 24 system in that its hydraulic cylinder 73 operates against a lever arm 74 which is rigidly secured to a leg of the scissors.

The personnel-supporting platform 24 preferably includes a central framework 75 and foldable and

removeble walkways

76 and 77 along each side as shown in FIGURES l, 3, 13 and 18 for example. Each walkway is preferably an integral unit providing horizontal flooring and vertical outside safety railing. Each walkway is retained by a plurality of hooks 78 which fit over horizontal pins 80. The pins 80 are inside the open ends of tubular members 82 of the framework 75, thus providing lateral restraint for the hooks 78. Rotation of the walkways about the pins 80 below the horizontal is prevented by the abutment of the inside edge of the walkway with the underside of the platform framework 75 at contact areas 84.

Each

walkway

76 and 77 may be removed by lifting the hooks 78 off the pins 80. Further, the walkways can be pivoted upwardly to compactly fold over each other and the work tower when both of the tower platforms are in their lowered positions.

The

walkways

76 and 77 may be constructed primarily of wood if desired. However, they may also be of metal construction. The entire work tower 20 is preferably constructed with high strength yet relatively light weight materials for portability. Suitable tubular metal construction is shown in the drawings.

The work tower 20 provides both flexible operation and compact portability without requiring either manual exertion or auxiliary equipment. Both the operation and transportation can be accomplished by a single person operating the appropriate hydraulic valves, Outrigger components and the lever 58 without requiring a dock, crane or other equipment even though the work tower may be of a weight which would normally preclude manual movement. The work tower 20 is particularly suitable for the needs of building contractors who must make installations above the oor level. It may be constructed small eenough to be transported to any job site in a pickup truck. At the job site, it can be unloaded without assistance by manipulation of its own hydraulic outriggers. The work tower can then Ibe easily moved and positioned on itS integral wheels. When in position, it may -be stabilized by its own outriggers. The work tower can also turn itself completely on end so that it may move through narrow door openings. Both the equipment to be installed and the workers can be vertically positioned where desired by the raising of the tower platforms to the respective desired working heights. The personnel can work on both sides of the load on the walkways Or one walkway may be removed for clearance if desired.

For stabilizing the work tower 20, the outriggers may be arranged and positioned as shown :in FIGURES 1 and 2. The Outriggers are pivoted horizontally as previously described, and the extension arm 50 is positioned in the Outrigger arm 46 so that the pin lockable wheel 52 can be locked and forcibly brought to bear against the fioor by the Operation of the hydraulic cylinder 54.

FGURES 24 through 29 illustrates the steps of selfloading the work tower 20 Onto a vehicle. During unloading, the same steps are reversed.

In FIGURE 24, it may be seen that the Outrigger arms 46 and the extension arms 50 extend parallel the sides of the work tower. The extension arms 50 extend from the inner end of the Outrigger arms 46 with the caster wheel 51 down. Then, as shown in FIGURE 25, the hydraulic cylinder 54 is actuated and the second end 40 of the work tower is lifted above the vehicle floor level. At this point, the work tower is supported and movable on the wheels 36 at the first end 38 of the work tower and the caster wheels 51 on the extension arm. Thus, the work tower may be pushed forward until the second end 40 is over the vehicle iioor. Then the hydraulic cylinder 54 may be actuated to lower the wheels on the second end 40. Continued operation Of the hydraulic cylinder 54 can then lift the extension arm 5f) sufficiently for it to be removed, turned over and inserted in the outer end of the Outrigger arm 46 as shown in FIGURE 26. Further operation of the cylinder 54 then results in lifting the front end 38 above the vehicle fioor level so that it may be rolled into the truck on the wheels 52 and the wheels on the second end 40 as shown in FIGURES 27 and 28. The cylinder 54 may then be actuated again to lift the outriggers into a vertical position as shown in FIGURE 29.

It may be seen that there has been described herein a work tower which is extremely versatile and transportable. The apparatus described herein is presently considered to be preferred; however, it is contemplated that further variations and modifications within the purview of those skilled in the art can be made herein. The following claims are intended to cover all such variations and modifications as fall within the true spirit and scope of the invention.

What is claimed is:

l. A movable work tower adapted for compact storage and movement through a narrow opening comprising:

a horizontally disposed base having predetermined lateral dimensions and adapted to support said work tower on a generally horizontal first surface;

a personnel-supporting platform connected tO said base;

means for raising and lowering said personnel-supporting platform above the first surface, said personnel supporting platform in its lowered position and said base being of a combined thickness less than either of said predetermined lateral dimensions;

and Outrigger means pivotally connected to said base at a point to one side of the center thereof;

said Outrigger means being extendable from said base and having roller means for engaging the first surface;

said Outrigger means being adapted to tilt said base on end so said base is oriented vertically relative to said generally horizontal first Surface with said roller means serving to rollably support said work tower for movement through said confined opening and said Outrigger means being further adapted to provide lateral stabilizers for said work tower when said base is in its horizontal postion.

2. The work tower of claim 1 further including a work support platform On said personnel-supporting platform and means for independently raising and lowering said work support platform relative said first surface and said personnel-supporting platform.

3. A movable work tower comprlsing:

a base having first and second ends and wheels movably supporting said base on a 'horizontal first surface,

a personnel-supporting platform connected tO said Jbase,

means for raising and lowering said personnel-supporting platform above said first surface,

an elongate Outrigger arm having inner and outer ends,

each said Outrigger arm being pivotally connected for vertical and horizontal rotation about its inner end at opposite sides of said first end of said base,

anextension arm colinearly projecting from each said Outrigger arm,

said extension arm having lockable means for rollably engaging said first surface at its Outer end,

both said inner and outer ends of said Outrigger arm being adapted to selectively connect with said extension arm,

wheel means on said outer end of said Outrigger arm adapted to engage said first surface,

hydraulic means connecting between said Outrigger arm and said base for vertically pivoting said base relative to said Outrigger about said first end of said base,

and lever means, pivotally connected to said base adjacent said outrigger means, for lifting said base and said Outrigger means from said first surface for movement of said extension arm.

4. The work tower of claim 3 further including a work support platform on said personnel-supporting platform and means for independently raising and lowering said work support platform relative said first surface and said personnel-supporting platform.

5. A movable work tower comprising:

a base having first and second ends and adapted to support said work tower on a generally horizontal first surface,

a personnel-supporting platform connected to said base,

means for raising and lowering said personnel-supporting platform above the first surface,

and Outrigger means pivotally connected to said base,

said Outrigger means being extendable from said base and having means for engaging the first surface,

said Outrigger means being adapted to selectively vertically tilt said first and second ends of said base above the first surface and to provide lateral stabilizers for said work tower,

and lever means, pivotally connected to said base adjacent said Outrigger means, for lifting said base and said Outrigger means from said first surface for extension and retraction of said Outrigger means,

6. The work tower of claim 5 further including a Work support platform on said personnel-supporting platform and means for independently raising and lowering said work support platform relative said first surface and said personnel-supporting platform.

7. The work tower of claim 5 wherein said means for raising and lowering said personnel-supporting platform includes,

a scissors connector therebetween with at least two pivotally connected legs and lifting means moving said scissors connector between Opening and closing positions,

said lifting means including a hydraulic cylinder and a lever linkage pivotally connecting with said hydraulic cylinder and pivotally connecting with a first point on said scissors connector,

said lever linkage providing a lifting connection of said hydraulic cylinder with a second point on said scissors connector substantially spaced from said first point in said closing position of said scissors connector,

and said lever linkage providing a lifting connection of said hydraulic cylinder with said scissors connector only at said first point during the remainder of the movement of said scissors connector. 8. The movable work tower of claim '7 wherein said lever linkage is an elongate integral member having a fulcrum portion projecting at right angles thereto, said fulcrum portion engaging said second point of connection only in said closing position of said scissors connector.

9. In a portable work tower having an ambulatory base and a lift platform supported thereon, self-loading means adapted for lifting said work tower between generally horizontal rst and second surfaces at vertically spaced levels comprising:

rst lever means supported on the underside of said base adjacent one end thereof and adapted for pivotal movement about a generally horizontal axis;

second lever means comprising an elongated lever arm adapted for selective locking engagement with said first lever means in each of a first and a second position in which said second lever arm extends along a line generally parallel to the longitudinal axis of said Work tower in respective opposite directions from said first lever means;

and power operated actuator means coupled between said first lever means and said base for pivoting said rst lever means to displace, through coaction of said elongated lever arm and one of said first and second surfaces, one end of said work tower between said lirst and second surfaces when said elongated lever arm is in said rst position and for displacing the other end of said work tower between said rst and second surfaces when said elongated lever arm is in said second position.

10. The self-loading means of claim 9 in which said first lever means and said elongated lever arm of said second lever means are each comprised of a hollow channel member with said hollow channel of said first lever means being of internal dimensions for snugly receiving one end portion of said elongated lever arm therewithin and in which said first lever means and said elongated lever arm are selectively maintained in locking engagement by a bolt extending through aligned apertures in said hollow channel members.

11. The self-loading means of claim 10 in which said power operated actuator means comprises a hydraulically operated piston and cylinder arrangement with said piston and said cylinder being each pivotally mounted to a respective one of said rst lever means and said base.

12. The self-loading means of claim 11 and including wheel means at each end of said elongated lever arm of said second lever means for rollably engaging said lirst and second surfaces. Y

13. A portable work tower for raising objects to a predetermined substantial height and for folding into a compactly stored unit comprising:

base means including a generally rectangular bed having wheels thereon supporting said base for rollable movement;

first platform means having a support deck and further having power actuated lifting apparatus for displacing said support deck between a lowered position substantially contiguous said bed of said base means and a raised position a predetermined distance above said bed;

second platform means, mounted on said support deck of said first platform means, having an associated support deck and further having power actuated lifting apparatus for displacing said associated support deck between a closed position substantially contiguous said support deck of said first platform means and a raised position a'predetermined distance above said support deck of said lirst platform means;

and a pair of personnel carrying platform means hingedly mounted to opposed sides of said support deck of said second platform means and pivotable inwardly from normal work positions lateral of said second platform means toward one another to lie in overlapping relation on said lowered support deck of said second platform means to effect a compact storage of said personnel carrying platform means.

14. The work tower of claim 13 in which said pair of personnel carrying platform means each comprise a personnel supporting deck and a guard rail mounted about the outer periphery about said deck.

References Cited UNITED STATES PATENTS 1,577,989 3/ 1926 Sieber 182--69 2,656,942 10/ 1953 Helms 214-515 2,843,430 7/ 1958 Johnson 182-63 2,935,218 5/1960 Fritz 182-63 3,015,497 l/1962 Aldred 182-17 3,259,369 7/1966 Gridley 182-141 3,283,831 1l/1966 Bronder 214-515 3,411,646 11/1968 Emery et al 254-45 REINALD P. MACHADO, Primary Examiner U.S. Cl. X.R.