US3063514A - Retractable scaffold - Google Patents

Description

. Nov. 13, 1962 KAZUO HlYAMA .l RETRACTABLE SCAFFOLD 3 sheets-sheet 1 Filed March 13. 1961 ,wl V Illlllllllll KAZUO 'l/VAMA /NVENOR HUEBNER 8 WURREL Now-13, 1962 KAZUOA HIYAMA .A

RETRACTABLE sc'AFFoLD Tile@ Marcnl. 1961 3 Sheets-Sheet 2 Filed March 13, 1961 RETRAC'TABLE SCAFFOLD 3 Sheets-Sheet; 3V

KAZUO H/YAMA Husa/v5@ s Wamel. Arme/vans l 46 United States Patent ce i j 3,963,514 Patented Nov. 13, 1952 3,063,514 RETRACTABLE SCAFFOLD Kazuo Hiyama, 8184 E. Adams Ave., Fowler, Calif. Filed Mar. 13, 1961, Ser. No. 95,419 13 Claims. (Cl. 182`63) The present invention relates to la retractable scaffold and more particularly to a simple, compact, and stable mobile scaffold including a relatively large platform for supporting one or more workmen and which is movable between a work position in elevationally adjacent relation to an upright object, such as a tree, and a retracted position wherein the overall transverse dimensions of the scaffold are reduced to facilitate earth traversing movement.

The scaffold of the present invention was developed for use in orchard care although the invention is not to be limited to such use. Nevertheless, it is convenient to refer to the care of an orchard in briey describing certain problems solved by the subject invention.

For thinning, picking and pruning trees, it is conventional to employ ladders. Of necessity these ladders must be large enough to enable access to the upper branches; therefore, they are usually heavy and cumbersome to handle. Accordingly, care of orchards is a tedious and time consuming task.

-For the foregoing reasons and the general trend toward farm mechanization, considerable effort is currently being devoted to the development of a relatively simple, compact and stable mobile orchard scaffold. My prior copending application Serial No. 17,9017, filed March 28, 1960 discloses a mobile scaffold excellently suited to the described purposes. The subject application is an improved form of scaffold of the type shown in my prior application cited above.

Accordingly, it is an object of the present invention to provide a retractable mobile scaffold including a relatively large workman support platform but which is relatively simply, compact, and stable.

Another object is to minimize the time and effort involved in pnlning, thinning, and picking trees in an orchard.

Another object is to provide a retractable mobile scaffold including a support platform mounted for movement between an outwardly extended, substantially horizontal, work poistion and a retracted position wherein the overall dimensions of the scaffold are reduced to facilitate earth traversing movement thereof.

Another object is to provide a retractable scaffold including a workmans support platform which is easy to move between a substantially horizontal work position and an upwardly extended retracted position.

Another object is to provide a retractable scaffold including a pair of platforms movable between a coplanar work position and an inverted V-shaped retracted position, wherein the platforms are dependably releasably sup-ported in said work position, but wherein they are readily urged toward said retracted position upon release from said work position.

Another object is to provide a mobile orchard scaffold adapted for movement between a pair of adjacent rows of trees in an orchard and being further adapted for movement into a workmans support position enabling access to a plurality of trees in each of said rows.

These, together with other objects, will become more fully apparent upon reference to the following description and accompanying drawings.

In the drawings:

FIG. l is a top plan view of a retractable scaffold embodying the principles of the present invention, showing a pair of platforms in coplanar -work position, and further showing hidden portions of the scaffold beneath the platforms in dashed lines.

FIG. 2 is a side elevation of the scaffold shown in FIG. l.

FIG. 3 is a somewhat enlarged end view taken from a position represented -by line 3 3 in FIG. 1, showing the platforms in a retracted position in dashed lines, and further showing a pair of trees in adjacent rows of an orchard in dashed outline.

FIG. 4 is a horizontal section taken 0n line 41H4 in FIG. 3 but with the scaffold being broken away centrally thereof for illustrative convenience.

FIG. 5 is a somewhat enlarged, longitudinal vertical section taken on line 5-5 in FIG. 4.

FIG. 6 is a fragmentary, somewhat enlarged, end elevation taken from a position indicated by line 6 -6 in FIG. 4.

FIG. 7 is a fragmentary, somewhat enlarged detailed end view taken from a position indicated by line 7 7 in FIG. 2.

Referring more particularly to the drawings, a mobile frame 15 is shown in FIGS. l, 2 and 3. The frame has a substantially horizontal base 16 including a front axle 17, a rear axle 18, and opposite, longitudinally extended, side members 19 rigidly interconnecting the front and rear axles in spaced, substantially parallel relation, as best illustrated in FIG. l. Further, elongated cross-members 20 have opposite ends rigidly connected to the front and rear axles adjacent to the connections of the side members. These cross-members are extended transversely of the frame in X-shaped relation and impart rigidity to the base of the frame.

Rear wheels 25 are journaled on opposite ends of thc rear axle 18 while front wheels 26 are rotatably mounted on opposite ends of the front axle 17 for steering movement about vertical axes as well as about horizontal axes. Steering arms 27 are rigidly radially forwardly extended from the vertical pivot axes of the front wheels, and an elongated steering bar 28 pivotally interconnects the arms in forwardly spaced, parallel relation to the front axle. An elongated drawbar 29 provides a rear end pivotally connected to the axle 17. The drawbar is likewise pivotally connected to the Vsteering bar 28 and forwardly eX- tended for connection to any suitable draft appliance, not shown.

With particular reference to FIGS. 3 and 4, brackets 35 include base flanges 36 rigidly connected to the front and rear axles 17 and 18 adjacent to opposite ends thereof by clamps 37. It is to be noted that the brackets are closely outwardly adjacent to the side members 19 but are inwardly spaced from the wheels 25 and 26. Each bracket also has a mounting ilange 38 in acute angular relation to its respective base flange with opposed mounting iianges on each axle being divergently upwardly extended therefrom.

The frame 15 also includes front and rear pairs of elongated sleeves 45. Each sleeve has a lower end portion 46, an upper end portion 47, and an elongated slot 48 extended longitudinally thereof. The lower end portions of each pair of sleeves are rigidly connected to the mounting flanges 38 at their respective ends of the frame, as by welding. The sleeves of each pair `are convergently upwardly extended in the plane of their corresponding front or rear axles 17 or 18 with their upper end portions in intersecting relation at 50. Furthermore, each pair of sleeves is rigidly interconnected, as by welding, at said intersections. It is evident, therefore, that the pairs of sleeves are in upstanding, X-shaped relation. Furthermore, the sleeves are of uniform construction and their points of intersection are in `longitudinal alignment relative to the frame and substantially equidistantly spaced from the base 16. Additionally, the slots in the sleeves are upwardly disposed. Elongated tie members -2 are extended in X-shaped relation on opposite sides of the frame and provide front and rear ends 53 individually connected to the upper and lower end portions of the sleeves on corresponding sides of the frame rigidly to hold the sleeves in position.

.Elongated rods S5 are individually slidab-ly `fitted in the sleeves 45 and provide upper and lower portions 56 and 57. Lugs 58 are rigidly radially outwardly extended through the slots 48 from the lower portions of the rods. It is also to be understood that the rods are of uniform length.

A pair of substantially rectangular platforms 60 is provided. Each platform has transversely spaced, substantially parallel inner and outer edges 61 and 62 and longitudinally spaced, substantially parallel front and rear edges 64 and 65. Each platform has a substantially semicircular, intermediate opening 67 notched inwardly from its outer edge and front and rear, substantially quartercircle openings 68 notched out of the outer corners of the platform.

The platforms 60 are interconnected along their inner edges 61 by an elongated hinge 75. The platforms are thus pivotally interconnected for movement about a predetermined axis between a coplanar position land a `\{`-shapecl position. Abutments 76 are rigidly secured to the upper surface of each platform adjacent to the inner edge thereof. The abutments are engageable in the coplanar position of the platform to limit pivoting movement of the platforms beyond said coplanar relation and to relieve strain on the hinge. Ears 77 are rigidly downwardly extended from t-he lower surface of each platform outwardly of the inner edge thereof with the ears on each platform being longitudinally spaced from each other substantially the same distance as the longitudinal spacing between the front and rear pairs of sleeves 45 and rods 55. The platforms are mounted on the frame lby pins 78 individually pivotally interconnecting the ears and the upper portions 56 of the rods. More specifically, the platforms are mounted with the longitudinal pivotal axis of the hinge 75 extended longitudinally of the frame and substantially parallel to the pins '78, that is, the pivotal axes of interconnection between the rods and the platforms. The hinge is disposed downwardly toward the frame while the abutments are directed upwardly 'from the platforms. When mounted in this manner, the platforms are movable between a substantially horizontal work position in coplanar relation to each other when the rods are outwardly extended from their respective sleeves, and a retracted position with the platforms in inverted V-shaped relation, with the inner edges spaced above the plane of t-he platforms in work position, and with the outer edges of the platforms spaced inwardly of the wheels 25 and 26. Furthermore, the rods are retracted within the sleeves when the platforms are in retracted position. In said work position, the outer edges of the platforms are outwardly spaced from the wheels, and the abutments 76 preclude movement of said inner edges :below the work plane of the platforms.

Idler pulleys 80 are journaled in brackets 81 secured to the lower end portions 46 of the sleeves 45 downwardly spaced from the intersections 50 of the sleeves. A main control winch is generally indicated by the numeral 85 and includes multiple front and rear sheaves 86 rotatably mounted on the frame adjacent to the intersections 50 of the front and rear pairs of sleeves. The axes of rotation of the sheaves are in coaxial alignment and are substantially parallel to said pivotal axis of the hinge 75. An elongated shaft 87 rigidly linterconnects the sheaves, and a crank 8S is connected to an end of the shaft adjacent to the forward pair of sleeves, as best illustrated in FIGS. 2, 4, and 5. As shown in FIG. 7, a ratchet-type latch 89 interconnects the frame 15 and the shaft so that the shaft is rotatable in lboth directions when the latch is released but is precluded from rotating in one direction when the latch is in a latching position.

The winch provides platform cables 95 individually connected to sections of the front and rear sheaves 86. The platform cables have ends 96 upwardly extended from the sheaves and connected to the hinge 75. The winch also provides rod cables 98 wound about other sections of the front and rear sheaves and providing ends 99 and 100. One of the ends of each rod cab-le extends outwardly from its respective sheave and is connected to the .lug 58 on one of the rods 55. The other end of each rod cable is extended outwardly from its respective sheave, trained about one of the idler pulleys 80, and also connected to the corresponding lug. The cables are tensioned about their respective pulleys and sheave and are thereby in frictional engagement therewith.

With reference to FIG. 2, substantially horizontal plates areV rigidly extended inwardly of the frame 15 from a sleeve 45 in each pair of sleeves. Front and rear slide members 106 have upper ends 107 pivotally connected to the hinge 75 above the plates and lower end portions downwardly slidably extended through the plates. Collars 109 are longitudinally, adjustably slidably connected to the slide members above the plates, and setscrews 110 extend transversely through the collars for releasable engagement with the slide members for selective positioning of the collars on the slide members. Coiled compression springs 112 individually encircle the slide members and are positioned between the corresponding plates and collars. When the platforms are moved into work position, the springs are placed under compression .by movement of the collars downwardly toward their respective plates. The platforms are held in said work position by engagement of the latch 89. Upon release of the latch, the springs urge the inner edges of the platforms upwardly out of coplanar relation. While the described plates, slide members, collars, and springs are excellently suited for moving the platforms out of coplanar relation, in another form of the subject invention, the outer edges 62 of the platforms are weighted so that the platforms are gravitationally urged toward an inverted V-shaped relation when the latch is released. Further, movement of the platforms toward inverted, V-shaped relation can be effected by an outward shifting of weight on the platforms, as for example, by movement of the workmen voutwardly toward the outer edges of the platforms.

Operation The operation of the described embodiment of the su-bject invention is believed to be readily apparent and is briey summarized at this point. As previously stated, the subject scaffold is conveniently described in connection with the care of an orchard. For this purpose, two trees. in an adjacent pair of rows of trees in such an orchard are generally indicated by the numeral in FIG. 3.

If it is desired to prune the trees '120, for example, the scaffold is drawn longitudinally between the rows of trees with the platforms 60 in retracted position, as illustrated in dashed lines in FIG. 3. It is to be noted that the outerv edges 62 of the platforms are spaced inwardly of the wheels 25 and 26 so as to minimize the overall transverse dimension of the scalfold and to facilitate its earth traversing movement between the rows of trees. Preferably, the scaffold is pulled by a tractor -or other draft appliance, not shown, which is connected to the drawbar 29.

The scaffold is stopped between the rows of trees 120 with the intermediate openings 67 individually located opposite to a pair of transversely aligned trees in said rows. The crank 88 is rotated to wind the cables 95 and 98 about the sheaves 86. This moves the inner edges 61 of the platforms 66 downwardly and inwardly, and the lower portions 57 of the rods 55 upwardly and inwardly, toward the intersections 50 of their respective sleeves 45. By thus moving the inner edges of the platforms downwardly and the outer edges of the platforms outwardly and upwardly, the platforms are moved into their work position, as shown in full lines in FIG. 3. The platforms are moved against the urgence of the springs 112 and until the abutments 76 are brought into engagement. The latch 89 is pivoted into a latching position, as illustrated in FIG. 7, whereby the shaft 87 is precluded from rotating in such a direction as to allow the springs to move the inner edges of the platforms upwardly. The latch thereby releasably precludes movement of the platforms out of work position.

In swinging the platforms 66 from retracted position to work position, the intermediate openings 67 of the platforms of? move upwardly about their adjacent trees 120 so that the platforms extend about substantially half of the trees. The front and rear corner openings 68 receive about one-quarter of transversely aligned trees positioned forwardly and rearwardly of the trees received in the intermediate openings. Workmen then ascend the platforms where they are conveniently positioned for pruning the portions of the trees adjacent to the platforms.

When the pruning is completed to the degree possible, the workmen descend from the platforms 60. The latch 89 is released whereupon the springs i12 move the inner edges 61 of the platforms 6% upwardly out of coplanar relation. The platforms are then fully collapsed for transport by telescopically retracting the rods 55 into their respective sleeves 45. This is readily accomplished by rotating the winch SS in such a direction that the cables 98 pull downwardly on the rods. The scaffold is then moved longitudinally of the rows of trees 12o until the intermediate openings 67 are opposite to the transversely aligned pair of trees forwardly adjacent to the trees which were previously partially circumscribed by the front corner openings 63. The platforms are returned to operable position by rotating the winch 35 in the opposite direction telescopically to extend the rods 55 from their sleeves 45. As the inner edges of the platform descend in the return of the platforms to work position, the spring lf2 is compressed so as to be preconditioned for subsequent collapse of the platform for transport. Excessive downward' movement of the inner edges is precluded by the engagement of the abutments 76.

It is believed evident that when the platforms 60 are moved into work position, the rear corner openings 68 partially circumscribe those trees which were previously partially received in the front corner openings. When the inwardly disposed sides of a pair of adjacent rows of trees are pruned in this manner, the scaffold is driven between the next adjacent pair of rows of trees and the operation is repeated. In this manner the entire orchard is rapidly pruned.

From the foregoing, it will Vbe evident that a retractable, mobile scaffold has been provided which is relatively simple, compact, and stable, notwithstanding its provision of large platforms capable of supporting several workmen for movement over a wide area. The scaffold has a relatively low center of gravity and provides a collapsed or retracted position wherein its overall transverse dimension is reduced to facilitate maneuverability and earth traversing movement. The scaffold is easy to adjust or move between work and retracted positions, is dependably maintained in work position, and is durable in construction to withstand rugged treatment in the held.

Although the invention has been herein shown and described in what is conceived to be the most practical and preferred embodiment, it is recognized that departures may be made therefrom within the scope of the invention, which is not to be limited to the details disclosed herein but is to be accorded the full scope of the claims so as to embrace any and all equivalent devices and apparatus.

Having described my invention, what I claim as new and desire to secure by Letters Patent is:

1. A scaffold comprising an elongated mobile frame, a pair of elongated platforms having pivotally interconnected inner edges, disposed longitudinally of the frame,

and telescopic means mounted on the frame and pivotally connected in sole supporting relation to the platforms at fixed positions on the platforms in spaced relation to said inner edges, said means being adapted correspondingly to reciprocate the positions of connection to the platforms along upwardly divergent downwardly convergent paths whereby the platforms are folded for transport upon downward movement of said positions and whereby the platforms are drawn into substantial horizontal alignment for load support upon upward movement of said positions.

2. The scaffold of claim 1 including resilient means engageable with the inner edges of the platform to urge said inner edges upwardly when the platforms are in substantial horizontal alignment.

3'. A mobile scaffold comprising a mobile frame having opposite ends; a pair of corresponding telescopic members mounted at each end of the frame, the telescopic members of each pair having lower ends connected in spaced relation to the frame, intermediate portions rigidly interconnected, and upwardly extended upper ends; a pair of platforms having pivotally interconnected inner edges; said platforms being individually rested on corresponding upper ends of the telescopic members with the inner edges of the platforms disposed in substantially vertical alignment with the interconnected intermediate portions of the telescopic members; means pivotally connecting the platforms to the upper ends of the telescopic members on which they are rested; and powered means connected to the telescopic members for corresponding extension and contraction thereof.

4. In a workmans retractable support; a base; a pair of platforms having opposite inner and outer edges; means pivotally interconnecting the inner edges; means borne by the base mounting the platforms on the base for movement about spaced substantially parallel, horizontal elevationally adjustable axes between a work position with the platforms in a substantially common-horizontal plane, and a retracted position with said platforms in inverted V-shaped relation, said mounting means mounting the platforms for elevational movement of their respective axes along upwardly divergent downwardly convergent reciprocal paths; and platform moving means connected to said mounting means and to the platforms adjacent to their inner edges for elevationally moving said inner edges along a common, upright, substantially rectilinear path while moving said axes along said divergent-convergent paths whereby the platforms are moved between work and retracted positions respectively.

5. A mobile scaffold comprising a base mounted for earth traversing movement and having opposite sides; a pair of platforms having opposite inner and outer edges; means pivotally interconnecting the inner edges of the platforms for movement about a predetermined axis substantially parallel to said inner edges; means connected to the platforms in outwardly spaced relation to said inner edges and mounting the platforms on the base for movement between a work position with said platforms and edges thereof in a common substantially horizontal plane and with the outer edges of the platforms spaced outwardly of their respective sides of the base, and a retracted position with the platforms in inverted V-shaped relation to each other, with said inner edges spaced upwardly from said common plane, and with said outer edges spaced inwardly of their respective sides of the base; and powered means borne by the base and connected to the platforms and to said mounting means for moving the platforms between said work and retracted positions.

6. In a scaffold, a substantially horizontal base, a sleeve rigidly upwardly extended from the base in acute angular relation therewith, an elongated rod longitudinally slidably fitted in the sleeve, a platform pivotally mounted on the rod, and means borne by the sleeve and being connected to the rod and to the platform for moving the rod outwardly of the sleeve and the platform into a position substantially parallel to the base, and for moving the I rod inwardly of the sleeve and the platform into oblique angular relation to the base.

7. The scaffold of claim including abutments mounted on the platforms and engageable with each other in said work position for precluding movement of the inner edges below said common plane.

S. The scaffold of claim 5 wherein the platforms are substantiall 1 uniformly rectangular with said inner and outer edges in substantially parallel relation to each other, and wherein the platforms provide openings notched inwardly from said outer edges.

9. In a scaffold, a substantially horizontal base, a sleeve rigidly upwardly extend from the base in acute angular relation therewith, an elongated rod longitudinally slidably fitted in the sleeve, a platform mounted on the rod for pivotal movement about a predetermined axis substantially parallel to the base and having inner and outer portions extended in opposite directions from the pivotal connection of the platform to the rod, a sheave borne by the sleeve for rotation about an axis substantially parallel to the pivot axis of the platform, cables wound about the sheave individually connected to the inner portion of the platform and' to the rod on the opposite side ofthe sheave from the platform, means connected to the sheave for imparting rotation thereto thereby sliding the rod longitudinally of the sleeve for enabling movement of the platform between a position substantially parallel to the base and a position in oblique angular relation to the base, and means borne by the sleeve engageable with the platform for limiting movement thereof in said substantially parallel position.

10. A scaffold comprising a substantially triangular, upright frame having a substantially horizontal base and a pair of sleeves, the sleeves providing lower end portions rigidly connected to the base and upper end portions convergently upwardly extended and being rigidly interconnected in intersecting relation to each other; elongated rods providing lower portions individually slidably fitted in the sleeves and opposite upper portions; platforms having opposite inner and outer edges; hinge means interconnecting the inner edges of the platforms for hinging movement about a predetermined axis; means individually pivotally connecting the platforms tothe upper portions of the rods intermediate the inner and outer edges of the platforms with said predetermined axis in a plane substantially normal to the base and with the axes of pivotal connection of the rods and platforms being substantially parallel to said predetermined axis; and platform moving means mounted on the sleeves adjacent to their intersection and being connected to the hinge means and to f the lower portions of the rods for concurrently moving said hinge means and lower rod portions toward said intersection and for enabling concurrent movement of said hinge means and said lower rod portions away from said intersection whereby the platforms are movable between a substantially horizontal, coplanar work position and a retracted position in inverted V-shaped relation to each other.

y11. The scaffold of claim 10 wherein said moving means includes a winch having a sheave journaled in the frame for rotation about an axis substantially parallel tot said predetermined axis, and cables wound about the' sheave and connected to the hinge means and to the. lower rod portions.

l2. The scaffold of claim 10 wherein the sleeves aref provided with elongated slots; wherein lugs are secured".

to the lower portions of the rods and are extended out-V wardly through the slots in their respective sleeves;v

wherein idler pulleys are rotatably mounted on the sleevesY in downwardly spaced relation to their respectively adia-A cent lugs; and wherein the cables connected to the rods. are trained about the pulleys on their respective sleeves. and connected to the lugs of their corresponding rods.

13. The scaffold of claim 10 wherein a plate is mounted on the frame below said hinge means, wherein an clon-- gated slide member is pivotally connected to the hinge means and downwardly slidably extended through the plate, wherein a collar is connected to the slide member above the plate, and wherein a compression spring is interposed the plate and the collar in encircling relation to the sliding member, the spring being placed under compression in the work position of the platforms for yieldably urging the inner edges of the platforms above the common plane of the platforms in said work position; and wherein said control means includes a latch for releasably holding the platforms in said work position.

References Cited in the tile of this patent UNITED STATES PATENTS 284,308 Klein Sept. 4, 1885 476,400 Morgan et al. lune 7, 1892 568,999 Young Oct. 6, 1896 1,056,271 `Fredericltson Mar. 18, 1913 1,201,017 Brand Oct. 10, 1916 1,362,944 Kirby Dec. 21, 1920 2,003,581 Daly June 4, 1935 2,471,901 Ross May 31, 1949 2,672,319 Nelson Mar. 16, 1954 2,767,032 Mitchell Oct. 16, 1956 2,772,935 Read Dec. 4, 1956 2,843,430 Johnson July 15, 1958 2,879,120 Howe et al Mar. 24, 1959 2,917,129 Grover Dec. 15, 1959 2,959,244 Fedde NOV. 8, 1960 FOREIGN PATENTS 136,208 Australia Feb. 3, 1950 482,265 Germany Sept. 10, 1929

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