Telescoping Ladder

Abstract

A telescoping ladder having a lower section with the rungs fixedly secured to the side rails. Additional side rails telescope into the side rails of the lower section and can be telescoped out of the lower section to extend the side rails. Removeable rungs are mounted in the telescoped side rails to provide a relatively rigid ladder of the desired length.

Description

BACKGROUND OF THE INVENTION

FIELD OF THE INVENTION

The present invention relates to telescoping ladders.

SUMMARY OF THE INVENTION

The telescoping ladder of the instant invention has a lower section with rungs rigidly secured thereto. Side rails telescope out of the side rails of the lower section and are connected by removeable rungs which are clamped tightly into place therein forming a relatively rigid ladder.

The primary object of the invention is to provide a telescoping ladder which can fit easily into the trunk of a motor vehicle and which can be opened to any desired length.

Other objects and advantages will become apparent in the following specification when considered in light of the attached drawings.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a perspective view of the invention in partially extended position;

FIG. 2 is a perspective view of the invention in collapsed position;

FIG. 3 is an enlarged fragmentary vertical sectional view, taken along the line 3--3 of FIG. 1, looking in the direction of the arrows;

FIG. 4 is an enlarged fragmentary vertical sectional view of the foot attachment structure;

Fig. 5 is an enlarged fragmentary horizontal sectional view, taken along the line 5--5 of FIG. 1, looking in the direction of the arrows;

FIG. 6 is a fragmentary vertical sectional view, taken along the line 6--6 of FIG. 5, looking in the direction of the arrows;

FIG. 7 is a fragmentary end elevational view, taken along the line 7--7 of FIG. 6, looking in the direction of the arrows;

FIG. 8 is a fragmentary vertical sectional view, taken along the line 8--8 of FIG. 6, looking in the direction of the arrows;

FIG. 9 is an enlarged fragmentary vertical sectional view, taken along the line 9--9 of FIG. 6, looking in the direction of the arrows;

FIG. 10 is a fragmentary elevational view shown partially broken away and in section of the central portion of a rung;

FIG. 11 is a fragmentary exploded perspective view of one rail and its rungs just prior to connection; and

FIG. 12 is a view similar to FIG. 9 with the wedge turned and in retracted position.

DESCRIPTION OF THE PREFERRED EMBODIMENT

Referring now to the drawings in detail, wherein like reference characters indicate like parts throughout the several figures, the reference numeral 20 indicates generally a telescoping ladder constructed in accordance with the invention.

The telescoping ladder 20 includes a pair of generally rectangular hollow side rails 21, 22. The side rails 21, 22 are rigidly connected together by rungs 23 which extend from the inner faces of the side rails 21, 22 without obstructing the hollow center of the rails 21, 22.

A foot 24 is provided for the lower end of each of the side rails 21, 22 and includes a rubber nonslip sole portion 25 secured to the lower face thereof. A pair of upstanding ears 26 are secured in spaced parallel relation to the foot 24 with each having an elongate slot 27 formed therein. A bolt or securing element 28 extends through the lower end of each of the rails 21, 22 and through the slots 27 in the ears 26. A wing nut or fastener 29 secures the bolts 28 to the rails 21, 22 so that the foot 24 may be easily removed when desired. The feet 24 are provided with transverse detents 30 which are adapted to receive the front or or rear edge respectively of the lower ends of the rails 21, 22 as can be seen in FIG. 4.

The ladder 20 in collapsed form as illustrated in FIG. 2 may be used as a ladder with the side rails in stored position.

The side rail 21 has a generally rectangular hollow side rail 31 telescopically mounted therein. The side rail 22 has a generally rectangular hollow side rail 32 telescopically mounted therein. A generally rectangular hollow side rail 33 is telescopically mounted in the side rail 31 and a generally rectangular hollow side rail 34 is telescopically mounted in the side rail 32. The side rail 21 is provided with an aperture 35 and a spring detent 36 is secured to the side rail 31 and is adapted to engage in the aperture 35 to limit the movement of the side rail 31 out of the side rail 21. A similar spring detent 36 prevents movement of the side rail 33 out of the side rail 31. The side rails 22, 32 and 34 are also similarly equipped. The side 31, 32, 33 and 34 are provided with a plurality of bores 37 which extend completely therethrough. The position of the bores 37 at the lower end of the side rails 31, 33 are at the very top of the next lower side rail for reasons to be assigned.

The side rails 31, 32, 33 and 34 are connected by a plurality of rungs indicated generally at 38. Each of the rungs 38 include a generally cylindrical tube 39 which extends substantially the complete distance between the side rails 31, 32 and the side rails 33, 34. The tube 39 has a pair of elongate slots 40 formed adjacent each end portion thereof and extending generally parallel to the axis of the tube 39. Each of the elongate slots 40 have an enlarged central portion 41 for reasons to be assigned. An elongate slot 42 opens inwardly from each end of the tube 39 for reasons to be assigned.

A tube 43 is telescopically mounted in one end of the tube 39 and is adapted to be extended through the bore 37 in the side rails 31, 32, 33 and 34. The tube 43 has a pair of diametrically opposed slots 44 in opposite sides thereof to permit the end portion of the tube 43 to be expanded. A pair of wedge members 45 are rigidly secured internally of the tube 43 to cooperate with a wedge plug 46 interposed therebetween. The wedge plug 46 can be turned 90 degrees to slide between the wedge members 45 without moving them apart and can be turned to engage the wedge members 45 so as to move them apart as the plug is moved inwardly of the rungs 38. A shaft 47 extends through the plug 46 and is secured to a nut 48 on the outer end thereof. A coil spring 49 is positioned in the plug 46 and is engaged by the nut 48 so as to resiliently connect the shaft 47 to the plug 46. The inner end of the shaft 47 is then at right angles to form a handle 50 which extends through a generally J-shaped slot 51 formed in the tube 43.

The tube 43 has a rib 52 formed thereon with a stop 53 formed on its inner end. The rib 52 is adapted to engage in a slot 54 formed in each of the bores 37. The rib 52 and stop 53 are adapted to engage in the slot 42 of the tube 39 to prevent relative rotation between the tube 39 and tube 43 as well as to prevent relative rotation between the tube 43 and the side rails 31, 33, 32, 34. The tube 43 has a spider 54 mounted therein with the shaft 47 slidably mounted therethrough.

The opposite end of the tube 39 has a tube 43' telescopically slidably mounted therein. The tube 43' has an inner reduced diameter extension 55 which telescopes in the tube 43 as can be seen in FIG. 6. The tube 43' with the exception of the reduced diameter extension 55 is otherwise identical to the tube 43 and operates in the same manner.

In the use and operation of the invention the rung 38 is positioned between a pair of the rails 33, 34 in alignment with the bores 37 therein. The handle 50 is pushed outwardly to force the tubes 43, 43' through the bores 37. The handle is pushed on outwardly so as to free the plug 46 from the wedge members 45 and it is then turned to bring the plug 46 into cooperation with the wedge members 45. The handle 50 is then moved inwardly to draw the plug member 46 into wedging engagement with the wedge members 45 and finally the handle member 50 is turned into the lock portion 56 of the slot 51. The cooperative movement of the plug 46 between the wedge members 45 forces the end portions of the tubes 43, 43' into binding locking engagement with the edges of bores 37 to lock the rungs 38 thereto.

When it is desired to remove the rungs 38 the reverse procedure is followed following which the rails 31, 32, 33, 34 are telescoped into the rails 21, 22 and the rungs are placed in a suitable container for storage and transport.

Having thus descirbed the preferred embodiment of the invention it should be understood that numerous structural modifications and adaptations may be resorted to without departing from the spirit of the invention.

Claims

What is claimed is:

1. A telescoping ladder comprising a pair of spaced apart parallel hollow side rails, a plurality of generally horizontal spaced apart rungs having their opposite ends rigidly secured to said side rails, additional side rails telescopically mounted in said side rails and adapted to move to an extended position with respect thereto, a plurality of rungs detachably secured to said additional side rails in generally horizontal spaced apart relation, means for releasably locking said named rungs to said additional side rails, the means for releasably locking said rungs to said additional side rails including hand actuated means, said hand actuated means including a plurality of wedge members for expanding the ends of said last named rungs in said side rails.

2. A device as claimed in claim 1 wherein means are provided on said rungs for selectively cooperating with means on said side rails for preventing relative rotation of said rungs with respect to said side rails.

3. A device as claimed in claim 2 wherein the means for connecting said last named rungs to said additional side rails includes telescopic tubes with the smaller tube adapted to extend through said additional side rails.

4. In a telescoping ladder, a pair of generally rectangular spaced parallel hollow side rails, rungs extending from the inner faces of the side rails and rigidly securing the side rails together without obstructing the hollow center of the rails, a foot is provided for the lower end of each of the side rails and each foot including a non-slip sole portion secured to the lower face thereof, a pair of upstanding ears secured in spaced parallel to the foot with each ear having an elongate slot therein, a securing element extending through the lower end of each of the rails and through the slots and the ears, a fastener securing the securing elements to the rails, said feet being provided with transverse detents for receiving the lower ends of the rails, additional side rails having a generally rectangular hollow formation telescopically mounted in said first rails, certain of said additional rails having apertures therein, spring detents secured to certain of said additional rails for engaging the apertures to selectively limit the movement of the additional rails out of the first named rails, certain of said rails being provided with a plurality of bores that extend completely therethrough, rungs connected to said additional rails and said rungs including a generally cylindrical tube that extends substantially the complete distance between the rails, said tubes having slots therein that extend generally parallel to the axis of the tube, each of the last named slots having an enlarged central portion, tubes telescopically mounted in one end of the last named tube and adapted to extend through a bore in certain of the rails, said last named tubes having diametrically opposed slots in opposite sides thereof to permit the end portion of the tubes to be expanded, wedge members rigidly secured internally of the last named tubes, wedge plugs interposed between said wedge members, and said wedge plugs capable of being turned 90.degree. to slide between the wedge members, a shaft extending through the wedge plug and having a fastener on the outer end thereof, a coil spring positioned in the wedge plug and engaged by the last named fastener for resiliently connecting the shaft to the wedge plug, the inner end of the shaft being arranged at right angles to form a handle, there being a slot in one of said tubes for projection therethrough of said handle, one of said tubes having a rib thereon that is provided with a stop, said rib adapted to engage in a slot in each of the bores, and one of said tubes having a spider mounted therein with the shaft slidably mounted in the spider, a tube having an inner reduced diameter extension that telescopes in one of the first named tubes.