US896406A

US896406A - Portable jib-crane.

Info

Publication number: US896406A
Application number: US38631907A
Authority: US
Inventors: Howard H Maxfield; George Clinton Gardner Jr
Original assignee: Individual
Current assignee: Individual
Priority date: 1907-07-31
Filing date: 1907-07-31
Publication date: 1908-08-18
Anticipated expiration: 1925-08-18

Description

En. 396.406. G EATENTED AUG. 1s, 190s.

' E. E. MAXEIELD R G. G. GARDNER, JR.

PORTABLE JIR CRANE.

APPLICATION FILED JULY 3l, 1907.

2 SHEETS-SHEET 1.

PATENTED AUG. 1,8, 1908- H. H. MAXFIELD @L G. C. GARDNER', JR.

PORTABLE .TIB CRANE. APPLIOATION FILED JULY a1, 1907.

avm-3.1mm

z SHEETS-SHEET 2.

UNITED STATES PATENT OFFICE.

HOWARD H. MAXFIELD AND GEORGE CLINTON GARDNER, JR., OF TRENTON, NEW JERSEY.

PORTABLE .TIB-CRANE.

To all whom t 'may concern:

Be it known that we, HOWARD H. MAX- FIELD and GEORGE CLINTON GARDNER, Jr., citizens of the United States, and residents of Trenton, in the county of Mercer and State of New Jersey, have invented certain new and useful lm rovements in Portable Jib- Oranes, of whic the following is a specication.

This invention relates to improvements in portable jib cranes and more particularly to that class of such cranes which are employed where the rapid unloading and loading of material and the removing of machine parts occurs frequently and great facility in shifting and moving the crane is desirable without requiring the necessity of guying or bracing the crane each time it has been shifted and the object of our invention is to provide a crane of this kind, which is strong and durable and reliable, and easy in action, and by means of which a load can be raised and lowered or shifted rapidly and which requires no anchorage on the iioor or ground or any guy line or similar brace.

ln the accompanying drawings, in which like characters of reference indicate like parts in all the iigures: Figure 1 is a side view of our improved crane, parts being broken away and others in section. Fig. 2 is an enlarged detail vertical section of the upper parts of the mast or standard. Fig. 3 is a plan view of the crane, parts being broken out and shown in section. Fig. 4 is an end view of the upper part of the crane parts being broken out and others shown in section, the hoisting cable being omitted. Fig. 5 is a sectional plan view of the line 4 4, ofFig. 4, parts of the base being broken away.

The entire crane rests and is secured upon a base plate 1 preferably made circular in shape and of cast iron and of dimensions proportionate to the size of the crane. On this base 1 is erected a standard or mast 2 which is composed essentially of three bars 3 preferably made of angle iron, but which can be made of rolled iron or cast metal of any other desired shape and which are suitably connected by one or more braces or cross pieces 4 on which for example, the winding gear 5 of any desired construction may be mounted.

Specification of Letters Patent.

Application :filed July 31,

The three bars, or more, forming the standard or mast, are united at their upper ends by a mast cap or center plate 6, the lower part or neck of which extends downward in the hollow-mast or standard formed by the bars and is securely riveted to the upper ends of said bars by a series of rivets 7 so that this mast cap or center plate firmly and securely unites and binds together the upper ends of the bars forming the mast or standard. The mast cap 6 is provided with an external annular rib 8, and the upper end of this inner center plate 6 is surrounded by an annular housing 9, made of two semi-circular sections bolted together by bolts 1() as shown in Figs. 1 and 3. This housing is provided in its inner face with an annular recess 11 for receiving the rib 8 and the

roller bearings

12 and 13 resting respectively against the upper and lower surfaces of the rib 8 and against the upper and lower surfaces of the recess 11, the rib 8 being wedge shaped and the upper and lower faces of the recess 1 1 shaped accordingly so that the

rollers

12 and 13 in the shape of a truncated cone can be used. The

rollers

12 and 13 take up the entire vertical thrust.

For the purpose of taking up any lateral thrust vertical anti-friction rollers 14 are mounted in recesses formed in the adjacent vertical faces of the central plate 6 andthe housing 9 beneath the rib 8 as clearly shown in Fig. 2. Webs 15 of any suitable shape project upward from the top of the housing 9 as is clearly shown in Fig. 3 and to these webs the channel bars or other rolled bars 16 are bolted which rolled bars form the boom of the crane and thus turn with the housing 9 on the center plate or cap 6.

The boom formed by the bar 16 is provided with a truss rod 17 secured at the rear or shorter end of the boom to a bolt 18 uniting the two rods 16 and at the front end of the boom to an upwardly extending bracket 18 by means of an eye and threaded end and nut connection so that the truss rod can be drawn up and tightened when necessary. The truss rod passes over a truss bearing 20 formed with standards bolted to the inner sides of the beams 16 and on the upper end of this truss bearing a suspension eye 2 1 is formed for receiving a hook attached to a cable by means of which the entire crane can readily v and is passed over two sheaves 25 between which it passes over the sheave 26 of the hoisting hook 27 and then passes over a sheave 28 on the truss bearing 20 and then' down through the center of the mast of the hoisting drum.

The sheaves 25 are mounted on a carriage 29 running on the boom, said carriage having flanged wheels 30, the flanges of which extend down on the inner sides of the beams 16 and the treads of the wheels 30 running on the upper edges of the beam 16 of the boom so as to prevent derailment of the carriage. These wheels are mounted on axles 31 upon which they rotate, said axles forming an arbor for the sheaves 25. As the boom is balanced and as the vertical and lateral thrust is taken up by the roller bearings, the boom may be freely rotated in any direction and by means of the hoisting drum the load can be brought to any point within the circle described by the length of the radius of the boom. The counter-weight 22 suspend ed from`the rear end of the boom a proper distance from the center of the mast in conjunction with the weight of the base always maintains the crane in a condition of stable equilibrium with a load at any point on the boom even when the load is suddenly started.

The operation is as follows When the load is to be raised the hoisting cable 23 is Wound on the Winding drum whereby the hoisting hook 27 is raised correspondingly. If the load is to be shifted to any point of a circle of a radius extending from the center of the mast to the point of suspension of the hook, the boom can easily be turned on the mast or central standard and if the load is to be moved to any point along the length of the boom, it is only necessary to apply a light force or pressure against the load in the direction in which it is desired to move the same. As the heavy base 1 and the counter-weight 22 balance all parts of the boom and even the load thereon it Willbe seen that no anchoring of the base nor of any parts or guying of the mast or standard is required thus affording the possibility of operating with this crane in a confined space and permitting of readily shifting the crane so as to bring it into most suitable position for performing its Worlr.

Having described our invention what we claim as newand desire to secure by Letters Patent is 1. 1n a crane, the combination with a supporting frame, of a center plate at its upper end, which center plate has an annular rib, a housing surrounding said center plate and having an internal annular groove, horizontal rollers contained in said housing and running on said rib of the center plate, and a boom secured to said housing, substantially as set forth.

2. In a crane, the`combination with a supporting frame, of a center plate secured in the top of the frame and having an external annular rib, a housing loosely surrounding the center plate, horizontal friction rollers in said housing and resting against the rib, a set of vertical rollers between the center plate and the rotative housing, and a boom secured on the housing, substantially as set forth.

3. In a crane, the combination with a supporting frame, of a center plate secured on the same and provided with an external annular rib having inclined top and bottom faces, a housing loosely surrounding the center plate and having a beveled internal annular Arecess provided with an inclined top and bottom, friction rollers in the shape of a truncated cone resting respectively between the upper surface of the rib and the top of the recess and the under surface of the rib and the bottom of the recess and a boom securedto said housing, substantially as set forth.

4. In a crane, the combination with an upright frame, of a center plate secured on the upper end of the same, a housing mounted rotatively on said center plate, and provided with upwardly projecting lugs, beams forming the boom resting on the Vhousing and riveted to said lugs, substantially as set forth.

5. In a crane, the combination with a base, with uprights secured to the base, a center plate connecting the vuprights at their upper ends, of a housing loosely surrounding the center plate and a boom attached to said housing, substantially as set forth.

6. ln a crane, the combination with a standard, of a boom mounted to turn'on the same, a truss frame on the boom, a truss rod having its ends connected with the end of the boom, and passing over said truss frame, and an eye secured on the upper end of the truss frame, substantially as set forth.

7. 1n a crane, the combination with a standard, of a center plate on the upper end of the same, a housing loosely surrounding the center plate, two eye beams bolted to the center plate and forming a boom, a truss frame bolted to the inner sides of the eye beams above the housing, an upwardly extending bracket riveted to the inner sides of the eyebeams at one end of the boom, a truss rod secured to said bracket, passing over the truss frame and secured to the opposite end of the boom, a sheave pvoted in the truss frame, a carriage on the boom,

sheaves on the carriage, a hoisting cable secured to said bracket and passed over the of Mercer and State of New JerseyT this 1.0

Signed at the city of Trenton in the county sheaves on the carriage and over the sheave twenty-Erst day of June A. D. 1907.

on the truss frame, a Winding drum with which the cable s connected, and a hoisting hook suspended from that part of the chain between the tWo sheaves on the carriage, substantially as set forth.

HOWARD H. MAXFIELD. G. CLINTON GARDNER, JR. Witnesses:

SCOTT SCAMMELL, v JOHN H. WooLvERToN.