US1342480A - Crane - Google Patents

Description

A. WELIN.

CRANE.

APPLICATION FILED IuLvzs. 1915.4

1,342,480. 1 Patenteuunes, 1920.

' the UNITED STATES ATENT OFFICE.

AXEL WELIN,

A COEPORATION 0F NEW YORK.

CRANE.

Specification of Letters Patent.

Patented June 8, 1920.

Application led J'uly 26, 1915. Serial No. 41,903.

To all whom t may concern:

Be it known that I, AXEL WELIN, a subject of the King of Sweden, residing at Hopetoun House, Lloyds avenue, in the city of London, England, have invented new and useful Improvements in Cranes, of which the following is a specification.

This invention relates to improved means for lufiing cranes, especially ships davits, and I will describe'it in connection with a davit.

lThe object of the invention is to provide a support for the crane or davit arm above its pivot when it is in the outboard position and thus to enable a lighter davit to be used, to reduce the size of the Jframe, and to provide a compact, inexpensive crane construction which may be manipulated to luff a load with great speed.

My invention is illustrated uin' the accompanying drawings, Figure l of which 1s a side view of one construction according to my invention and Fig. 2 is a similar view of a modication.

In said ligures a is a vertically-disposed frame at the footof which is mounted, so that it is turned about a horizontal pivot o, a crane arm c. Journaled in the frame is a worm (Z which can be rotated by means of a crank handle e and which meshes with a worm wheel f on a spindle g supported in elevated position and rotatably mounted in frame.

In Fig. l the spindle g has fast upon it an arm L the outer end of which is connected by a link z' to a pin j on the arm c at a point substantially opposite in a horizontal direction a part of the arc described by said arm The arm is shown in its limiting position in which the pin 7c, which forms the connection between the link z' and the arm h, is in the plane passing through the axes of the spindle g and the pin y'. In order to luft' the arm c inboard the crank handle is turned and the arm it turning clockwise pulls upon the link and luifs the arm. 4

In Fig. 2 the arm L is formed in one with a ring of teeth Z which mesh with Aa pinion m on the spindle, the other parts being the same as those shown in Fig. l.

It will be evident that owing to the fact that the arm c is supported at some distance above its pivot the bending stress due to the load will be less'than is the case in the ordinary construction where the arm is not supported above the pivot and consequently the arm may be considerably lighter, and furthermore that, owing to the elevation of the spindle g and arm it, and the connection of the link z' with the crane arm c at a point substantially opposite a portion of the arc described by the said arm it, power is exerted on the arm cin a substantially horizontal direction, and the most effective use of such power is thereby procured.

Vhat I claim is y The combination with a crane on a fixed pivot at its lower end to swing in a vertical plane, a vertically-disposed frame located contiguous to said pivot, a fixed spindle supported in said frame in an `elevated position, a turning member having a radial part movable in the arc of a circle above said spindle and to opposite sides thereof, means for actuating said radial part to move in opposite directions, and a connecting member pivoted at one end to said radial part and having a pivotal connection with the crane arm at its opposite end at a point on said crane arm substantially opposite in a horizontal direction a portion of the arc described by said radial part, whereby-l actuating power vmay be exerted on said crane arm in a substantially horizontal 'd1- rection.

AXEL I/VELIN.

arm pivoted

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