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Publication numberUS936681 A
Publication typeGrant
Publication dateOct 12, 1909
Filing dateMar 28, 1908
Priority dateMar 28, 1908
Publication numberUS 936681 A, US 936681A, US-A-936681, US936681 A, US936681A
InventorsFrank Loring Union
Original AssigneeFrank Loring Union
Export CitationBiBTeX, EndNote, RefMan
External Links: USPTO, USPTO Assignment, Espacenet
Ladder.
US 936681 A
Abstract  available in
Images(2)
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Claims  available in
Description  (OCR text may contain errors)

r. L.- UNION. LADDER. APPLICATION FILED MAR. 28, 1906.

936,681. Patented Oct. 12,1909.

a P. L. UNION.

Patented Oct. 12,1909.

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*FRAN'K LORING UNION, OF NEW YORK, N. Y.

LADDER.

Specification of LettersPatent.

Patented Oct. 12, 1909.

App'lication file'd March '28, 1908. Serial No. 423,978.

To all whom it may concern:

Be it kn own that I, FRANK LORING UNION, a citizen of the United States, residing at New York, borough of Manhattan, State of New York, have invented certain new and useful Improvements in Ladders, of which the following is a specification.

This invention frelates to ladders of the folding or collapsible type, and the object of the same is to provide a ladder which can be compactly collapsed 3 and stored away in small compass ready for use, and which can be quickly and easily extended foruse.

The improved ladder is built on the lazytongs principle, and consists of certain features of construction and combinations of parts to be hereinafter described and then claimed with reference to the accompanying drawings showing a desirable form of the invention, and in which,

Figure l is a perspective view of the ladder showing the same extended for use; Fig. 2 is a perspective view showing the ladder collapsed and stored in a small space near-the ceiling of a room; Fig. 3 an enlarged broken side elevation of the improved ladder; and Fig. 4 is a side elevation of the improved ladder showing its use in connection witha fire-escape balcony. V V p In Figs. 1 and 2 theimproved ladder is shown in a room of a building suspended from a sky-light :20, and in Fig. 4t it is shown suspended from a fire-escape balcony'y.

The ladder comprises sides a, Z), which are respectively composed of bars a, a and Z), I). The bars a, aare crossedand likewise the bars 71. b, and at the points of crossing are pivotally connected by means of pivot rods (Z which form rungs and which enable thetwo pairs of side bars to open and shut like scissors. The so connectedand pivoted side bars a, a and I), Were connected by means of pivot rodsr'l with other similarly formed sections a, 7)., (Z, these rods d forming the other rungs of the ladder, and connecting the side bars in such way as to form lazy-tongs sections, each consisting of two pivotally connected pairs of side bars at one side of the ladder, and two pivotally connected pairs at the opposite side, these pivotally connected pairs being multiplied and extended according to the number of lazy-tongs sections and length of ladder desired. The upper side bars 0, c and c 0 do not cross each'other, but are connected at their upper ends by one of the rungs (Z, while a similar rung likewise connects the uncrossed side bars 0 and 0*, 0* located at the lower end of and which constitute the'feet of the ladder.

In Figs. land 2 the described ladderis shown as "hung or suspended from a skylight w located in the ceiling of a room, this being accomplished through the medium of a pair of hangers e, c, which are suitably secured to the sky-light and which are provided with eyes or bearing portions 0, c in which is pivoted the upper rungd of the ladder. It will be seen that the ladder may be extended as shown in Fig. 1, or 001- lapsed as shown in Fig. 2, due to the lazytongs principle of its construction. One of the best ways to permit it to be extended or collapsed is to attach a rope or cable f to one of the lower rungs (Z and pass it upwardly overa suitable pulley or pulleys g which are suspended adjacent the sky-light w, the free end of the rope or cable supporting acounter weight 71 To overcome the counter weight it is only necessary to take hold of the weight and raise it, whereupon the weight of the ladder will cause its sections to be automatically extended into suband takes the place of the ordinary movablelower section or lower ladder of an 1ron fire-escape. In this case the ladder may be suspended so as tobe quickly released, by means of a hook Z pivoted to the fire-escape and engaging one of the rungs ofthelower l'aZy-tongs'section of theladder. The ladder inthis-case may also have means for raising it, as a rope or cable is which is attached to the lower lazy-tongs section of the ladder, which rope may be removably attached to the fire-escape balcony at m. When the ladder is collapsed out of use, the rope or cable lc may be drawn up tight and it is only necessary to disengage the hook 1 from the lower rung in order to permit the ladder to be quickly dropped by the rope and extended into using position. In this case the means of operating the ladder is slightly different from that shown in Figs. 1 and 2, wherein the parts are balanced similar to suspended harness used for fire horses.

construction herein described and shown may be modified without departing from the spirit and scope of the invention.

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

1. In a collapsible ladder for extending from an elevated point to a supporting surface, the combination of means for pivotally and terminally supporting the ladder at its upper end, duplicate lazy tongs constituting the two ladder sides, each of said lazy tongs consisting of a series of successive pairs of long intermediate bars or links, each twice the length of the ladder step, terminal pairs of bars or links at both the upper and lower ladder ends, the pivots for connecting together the two bars or links of each of said pairs being a first series, and the pivots for hinging the ends of each of said long links to the links above and below being a second series; a main series of rungs corresponding -to and coincident with said first series of pivots, a second series of rungs corresponding to and coincident with said second se- 2 rles of plvots at the ends of said longlinks whereby when the ladder is extended the rungs of the second series will alternate with those of the main series to reduce the length of ladder step, while when the ladder is collapsed the rungs will arrange themselves in three orderly groups, the entirety when extended being more than of length to reach the supporting surface, whereby it may rest on the supporting surface at its lower end with the ladder in inclined posi tion; and the second series of said rungs being a double series whereby the alternating ladder steps will have single and double rungs respectively; and means for retaining the ladder when not in use in collapsed position.

2. In a collapsible ladder for extending from an elevated pointto a supporting surface, the combination of means for pivotally and terminally supporting the ladder at its upper end, duplicate lazy tongs constituting the two ladder sides, each of said lazy tongs consisting of a series of successive pairs of long intermediate bars or links, each twice the length of the ladder step, terminal pairs of short bars or links of half the length of said long links at both the upper and lower ladder ends, the pivots for connecting together the two bars or links of each of said pairs being a first series, and the pivots for ninging the ends of each of said long links to the links above and below being a second series; a main series of rungs corresponding to and coincident with said first series of pivots, a second series of rungs corresponding to and coincident with said second series of pivots at the ends of said long links whereby when the ladder is extended the rungs of the second series will alternate with those of the main series to reduce the length'of ladder step, while when the ladder 1s collapsed the rungs will arrange themselves in three orderly groups, the entirety when extended being more than of length to reach the supporting surface, whereby it may rest on the supporting surface at its lower end with the ladder in inclined position, and the edges of the ends of certain of the links or bars abutting against the edges of the ends of certain other links or bars when the ladder is in fully extended position, and the second series of said rungs being a double series whereby the alternating ladder steps will have single and double rungs respectively; and means for retaining the ladder when not in use in collapsed position.

The combination with the wall of a skylight hole or the like, and means of support at one end thereof, of a. ladder attached at its upper end to said means of support, be low said wall, said ladder comprising lazytongs sides, rungs between them forming the pivots for the tongs, the upper of which rungs is the sole means of attachment to said means of support, and means for collapsing the ladder, said collapsed ladder leaving a free opening approximately onehalf the length of the sky-light between the joints directly under the sky-light and the opposite end of the said wall.

In witness whereof I have hereunto set my hand this 23d day of lvlarch, 1908.

FRANK LORING UNION. lVitnesses Gno. L. WHEELOCK, GERTRUon W. ldAn'rLINo.

Referenced by
Citing PatentFiling datePublication dateApplicantTitle
US3025925 *Mar 10, 1959Mar 20, 1962Chemring LtdLazy-tongs mechanisms, with particular application to foldable ladders
US3251330 *Nov 14, 1963May 17, 1966Honegger Herbert HMotor for docking boat
US5261645 *Sep 30, 1991Nov 16, 1993Huffman Charles EProjector ceiling lift
US5366203 *Jul 22, 1993Nov 22, 1994Safety Lock And Lift, Ltd.Projector ceiling lift
US5551658 *Aug 15, 1994Sep 3, 1996Chief Manufacturing, Inc.Projector lift system
US6073892 *Jun 11, 1996Jun 13, 2000Chief Manufacturing, Inc.Modular projector lift
US6585214Mar 28, 2001Jul 1, 2003Chief Manufacturing IncorporatedExtended travel lift mechanism for a flat panel display
US6637711Jun 8, 2001Oct 28, 2003Draper, Inc.Projector lift
US6986485 *Mar 22, 2004Jan 17, 2006The Boeing CompanyOverhead space access stowable staircase
US7080806Mar 26, 2004Jul 25, 2006The Boeing CompanyOverhead space access conversion monument and service area staircase and stowage system
US7631848Jun 5, 2002Dec 15, 2009Draper, Inc.Projector lift
Classifications
International ClassificationE04F11/06
Cooperative ClassificationE04F11/066
European ClassificationE04F11/06A2