US2476650A - Stepladder - Google Patents

Description

A. BIERY STEP LADDER July 19, 1949.

2 Sheets-Sheet 1 Filed Jan. 14, 1948 ArI/wr B/ery INVENTOR.

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a I m I N] s I iv: INF

A. 'BIERY STEP LADDER July 19, 1949.

2 sheetssheet 2 Filed Jan. 14, 1948 Fig. 2.

Fig. 7. /0 9 50 54 92 90 as Arthur B/er of the rear actuating bar 58 are provided with longitudinal slots 52 that slidably receive the guide pins 40 carried by the guide straps 36 of the rear base plates 34. Receivably engaged on the threaded ends of the pivot bolts 54 are nuts 84 that retain the actuating bar relative to the bolts 54 and which may be tightened for retaining the actuating bars in a selected adjusted or shifted position.

The upper portion of cross members 42 and 44 are each provided with a longitudinal notch58 adjacent one of their ends that communicate with the notches 45, so that there will exist a guide opening 68 between the cross members and the web portions of the guide and retaining plates 50. Slidably mounted in each of the guide openings 68 are the inner ends of a pair of looking or latch bars 18, the reduced outer ends 12 of which i are turned upwardly and are formed with suitable apertures to provide support cars 98 for locking bars or bolts 98, a portion of which is slidably received in the opening 14 provided in one of the forward side rails and one of the rear side rails. A pair of coil springs I and H12 are loosely carried by each of the locking bolts 98 and urge the arm 90 from the side rails and the bolts 98 from the openings 80 provided in the plates 18. In practical use of the device in modified form, the pivot bolts 54 are pulled downwardly in the notches 45, so that the locking bolts 98 disengage one of the openings provided in the plates 88.

' The rear and forward supports are then adjustare slidably received in openings 14 provided in one of the forward side rails I4 and a similar opening provided in one of the rear side rails l8. The inner ends of the locking bar 18 are provided with arcuate extensions or cams 16 that extend into the notches 46 for a purpose which will later be more fully described.

Recessedin the inner face of one of the forward extendable supports 28 and in the inner face of one of the rear extendable supports 30, are substantially rectangular plates 18 which are provided with a plurality of longitudinally spaced openings 88 that are adapted to register with the openings 14 provided in one of the forward side rails and one of the rear side rails and which receive the reduced ends I2 of the locking bars 10 for holding the extendable supports in an adjusted position. Loosely mounted on each of the locking bars 10 and biased between annular shoulders 82 on the locking bars and the inner faces of the side rails having the openings 14, are coil springs 84 that urge the reduced ends 12 of the locking bars 18 out of the openings 80 in the plates 18.

In practical use of the present invention, for adjusting the rearrextendable supports 30, the nut 84 is loosened so that the pivot bolt 54 may be pulled downwardly in the notch 46 provided in the rear cross bar 44. The rear actuating bar 58 is then pivoted, effecting an extension or downward movement of one of the rear supports 38 and a simultaneous shortening or upward move ment of the other of said rear supports 30. After the rear supports 30 have been adjusted to a selected position, the bolt.54 is pushed upwardly in the notch 46 so that the same will engage the arcuate end 18 of the locking bars 10 to force the reduced ends 12 of the locking bar into one of the openings 80 in the plate 18. The nut 54 is then tightened to retain the supports in a locked position. A similar procedure is followed for adjusting the forward supports 28.

Reference is now directed to Figure 7, wherein there is disclosed the means for locking the forward and rear supports 28 and 38 relative to the side rails of the step ladder in slightly modified form. In this embodiment, the notches 66 are not provided in the cross members 42 and 44 and the locking bars 10 are not employed. Fixed on the upper ends of the cross members 42 and 44, are guide pins 85 that are slidably received in guide slots 88 provided in support arms 90. The inner ends 92 of the support arms 90 are provided with integral, angular extensions 94 that are loosely positioned in the notches 46 formed in the cross bars. The outer ends of the arms 98 ed a selected length relative to the side rails of the step ladder. The pivot bolts 54 are forced upwardly in the notches 46 so that the extensions 94 engage the bolts 54, the support arms are forced away from the guide and retaining plates 50, and the locking bolts 98 are urged into the openings in the plates 18 that oppose openings 14. The nut 54 (not shown in Figure 7) is then tightened to hold the forward and rear supports in an adjusted position.

In view of the foregoing description taken in conjunction with the accompanying drawings it is believed that a clear understanding of the construction, operation and advantages of the device will be quite apparent to those skilled in this art. A more detailed description is accordingly deemed unnecessary.

It is to be understood, however, that even though there is herein shown and described a preferred embodiment of the invention the same is susceptible to certain changes fully comprehended by the spirit of the invention as herein described and the scope of the appended claims.

Having described the invention, what is claimed as new is:

1. In a ladder having a pair of side rails, a cross member extending between said side rails, a pair of slidable supports carried by said side rails, means for guiding the sliding movement of said supports, an actuating member pivotally carried by said cross member, means operatively connecting said actuating member, to said sup ports for simultaneous sliding movement of said supports in an opposite direction, a slidable looking bar carried by said cross member, means carried by one of said supports for lockably engaging said bar, means normally retaining said looking bar in a retracted position disengaged with said means carried by one of said supports for engaging said bar, and means carried by said actuating member for forcing said locking bar into a locked position.

2. The combination of claim 1 wherein said last mentioned means includes a pivot pin connecting said actuating member to said cross memher.

3. In a ladder having a pair of side rails, a cross member extending between said side rails, a pair of slidable supports carried by said side rails, means for guiding the sliding movement of said supports, an actuating member, a pivot pin slidably secured to the cross member and pivotally supporting the actuating member, means operatively connecting said actuating-member to said supports for simultaneous sliding movement of said supports in an opposite direction, a slidable locking bar carried by said cross member and actuated upon sliding movement of said pivot pin in one direction, means carried by one of said supports for lockably engaging said bar, and

means normally retaini g said. Iqckingbar in a, REFERENGCES CITED zzizisa sy zfii imiiziiziiis z sfiznzirgmzzm of in ii The combingtion of claim .3, ang a cam car- 5 STATES PATENTS 2;?.51;figiaz'zig assznizaszfifi aai ;252:: directwn' 8541152 De Cook Ma 21: 1 907 ARTHUR BIERY- 1,177,069 Verow et a1 Mar. 2a, 1916

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