US1737315A

US1737315A - Extension plank

Info

Publication number: US1737315A
Application number: US239122A
Authority: US
Inventors: Donald J Macdonald
Original assignee: Individual
Current assignee: Individual
Priority date: 1927-12-10
Filing date: 1927-12-10
Publication date: 1929-11-26
Anticipated expiration: 1946-11-26

Description

Nov. 26, 1929 D MacDQNALD 1,737,315

EXTENSION PLANK Filed Dec. '10, 1927 17 17 Dawn/d L7. MacDunD/d I'nvE'nfmY ing the bolt G therethrough.

Patented Nov. 26, 1929 s'rrs UNITE DONALD J. MACDONALD, OF CAMBRIDGE, MASSACHUSETTS EXTENSION PLANK Application filed December 10, 1927. Serial No. 239,122.

My invention relates to extension planks of the type adaptable for use by painters or other mechanics in building or repair work. It has for its purpose to provide a plank adjustable to varying lengths for convenience in use or shipping; to provide a graduated lap joint designed to avoid stumbling; to provide a simple and effective locking means designed to prevent slipping in use; to pro- 1 vide a hinge and swinging bolt construction designed to hold bolts from turning and to facilitate ease in dismounting; and to pro- Vide the various other advantages and results made evident from the following specification.

I accomplish the objects of my invention as shown in the accompanying drawings which form a part of this specification and in which Figure 1 shows my assembled plank in position for use. Figure 2 shows a sectional view on the line A-A in Figure 1. Figure 3 shows a detailed side View of my channel unit. Figure 3 shows a detailed plan View of my channel unit. Figure 4 shows a I plan View of the base unit. Figure 5 shows a top view of my assembled plank.

Referring again to the drawings B and C designate the respective plank units, the ends of which slide within the channel units comprising the parallel bars D and E. The tops of the channel bars are deslgnated D The sides are designated D and D The end of side 1) is bifurcated as shown in Figure 3 and the arms thereof are bentto form spaced eyes D The hinges are designated D The base fingers are designated E and E. The swinging bolts are designated as D and are pivoted on crosspins D carried in the eyes D The tightening nuts are designated as D. A series of orifices F in the plank units B and C are positioned so that two thereof may register when the planks B and O are at designated extensions, and when so registered a locking in fixed position is secured by pass- While I have illustrated and described a preferred construction for carrying my nvention into effect, this is capable of variatlon or modification without departing from the spirit of the invention. I therefore do not wish to be limited to the exact details of. construction herein set forth but desire to avail myself of such variations and modifications as come within the scope of the appended claims.

Having thus described my invention I claim as new and desire to secure by Letters Patent of the United States of America p 1. An extension device comprising a pair of superposed planks overlapping throughout a portion of their lengths and slidable longitudinally with respect to each other to increase the ovcr-all length of the device, said planks having registering openings for receiving positive and removable securing means therethrough, and the overlapping portions of said planks being received in spaced keepers, each of which engages about the upper surface of the top plank and down across the edges of both planks to holdthe planks in registry one above the other, and each keeper having a hinged clamping member extending across the bottom surface of the lower plank to clamp the planks together and retain them in the keepers.

2. A keeper for clamping extension planks together, comprising a pair of hingedly connected members, one of said members being substantially usshaped and having its ends bent substantially at right angles to the body portion and extending in the same direction to engage over and down the sides of a pair of superposed planks, the ends of said U- shaped member being bifurcated and the arms of the bifurcations being bent upwardly to form pair of eyes at the ends, another mem ber having an eye at one end bolted to form a hinge connection with the eyes on one end of the first named member, a swivel bolt carried by the eyes in the other end of the first named member, and the last named memher having a bifurcated end engaged by the swivel bolt to clamp planks between said members when the bolt is taken up. In testimony whereof I aflix my signature.

DONALD J. MACDONALD.