Title:
MOBILE LOAD HANDLING MACHINES
United States Patent 3856149


Abstract:
A mobile load handling machine primarily in the form of a crane is provided in which a jib is pivotally mounted from the machine chassis on upstanding mutually inclined linkage which interconnects front and rear wheeled portions of the machine chassis, which chassis portions are movable relative to one another along the fore and aft axis of the machine while ram means and tie linkage are pivotally connected between a mounting member movable in a fore and aft direction on one of the chassis portions and the jib whereby on extension and retraction of the ram means it operates in conjunction with the tie linkage to effect raising and lowering luffing movement of the jib and also operates in conjunction with the mutually inclined linkage to effect relative retraction of the chassis portions to reduce the wheel base of the machine on raising of the jib and vice versa.



Inventors:
SHAW D
Application Number:
05/367373
Publication Date:
12/24/1974
Filing Date:
06/06/1973
Assignee:
SHAW TREW & SMITH LTD,GB
Primary Class:
Other Classes:
180/432, 212/231, 280/638
International Classes:
B60P3/28; B62D21/14; B66C23/62; (IPC1-7): B62D5/06
Field of Search:
212/38,17,59,124,140,145,141,6,10 214
View Patent Images:
US Patent References:



Foreign References:
NL272937A
Primary Examiner:
Sheridan, Robert G.
Assistant Examiner:
Oresky, Lawrence J.
Attorney, Agent or Firm:
Watson, Cole Grindle And Watson
Claims:
I claim

1. A mobile load handling machine, comprising: a chassis having front and rear wheeled portions movable relative to one another along the fore and aft axis of the machine; upstanding mutually inclined linkage pivotally interconnecting said chassis portions; a jib supported by said linkage from the chassis portions; a mounting member movable in a fore and aft direction on one of the chassis portions; tie linkage pivotally connected between said mounting member and the jib; and ram means pivotally connected between the mounting member and the jib whereby, on extension and retraction of the ram means, said ram means operates in conjunction with the tie linkage to effect raising and lowering luffing movement of the jib and also operates in conjunction with the mutually inclined linkage to effect relative retraction of the chassis portions to reduce the wheel base of the machine on raising of the jib and vice versa.

2. A mobile load handling machine according to claim 1 wherein the ram means and mutually inclined linkage are pivotally connected to the jib about a common axis.

3. A mobile load handling machine according to claim 1 wherein the mutually inclined linkage is linked to the mounting member in order to stabilise the latter and the ram means and tie linkage in relation to the mutually inclined linkage.

4. A mobile load handling machine according to claim 3 wherein the mutually inclined linkage and the linking thereof to the mounting member define a parallelogrammic link formation with the ram means acting substantially diagonally in relation to said formation.

5. A mobile load handling machine according to claim 1 wherein one of the said chassis portions is provided with a longitudinal member slidably engaging the other chassis portion, said member having a swivel connection with the first mentioned chassis portion about the fore and aft axis of the machine to permit relative oscillation of the chassis portions about said axis.

6. A mobile load handling machine according to claim 1 wherein there is provided in combination with the machine fork lift means mounted at the front of the front chassis portion and operable separately or in conjunction with the jib.

7. A mobile load handling machine according to claim 6 wherein forks of the fork lift means are pivotally mounted from the latter whereby they may be swung back to an inoperative position especially for the purpose of operation of the jib.

Description:
The object of this invention is to provide an improved load handling machine primarily in the form of a crane for carrying out a variety of load handling operations. Practical advantages of the invention in this and various other respects and also constructional features will be apparent from the following disclosure.

In the accompanying drawings:

FIG. 1 is a side elevation of the machine or crane with the jib or boom lowered.

FIG. 2 is a cross section taken on the line II -- II of FIG. 1

FIG. 3 is a detail plan view of the front wheel steering and inturning mechanism

FIG. 4 is a diagrammatic elevation showing the machine with the jib or boom raised and the chassis retracted and

FIG. 5 is a diagrammatic elevation showing the machine provided with a fork lift attachment.

The chassis 1 comprises forward and rearward portions 2, 3 respectively carrying the front and rear wheels 4, 5, which portions 2, 3 are relatively movable or slidable in a fore and aft direction for obtaining variation in the distance apart or wheel base of the front and rear wheels 4, 5. Thus a rearwardly extending member or beam 30 from the forward chassis portion 2 slidably engages the rearward portion 3 between guide rollers 31 in the latter (see FIG. 2)

The beam 30 has a swivel mounting about the fore and aft axis at 35 with the forward chassis portion 2 to permit relative articulation or oscillation of the chassis portions 2, 3 about said axis when travelling over uneven ground.

A telescopic jib or boom 10 is pivotally connected by means of tie linkage 6 to a mounting member or carriage 7 longitudinally movable relative to the rearward chassis portion 3, which carriage 7 also pivotally carries at 38 a pair of hydraulic rams 8 which in turn are pivotally connected at their upper ends to the jib 10 at 9. In the retracted condition of the rams 8 the jib 10 assumes a substantially horizontal position as shown in FIG. 1 but on extension of the rams 8, the jib 10 assumes an upwardly inclined position as indicated in FIG. 4 with intermediate luffing of the jib 10 obtainable between these positions by appropriate operation of the rams 8.

Connected to the jib 10 at preferably the pivotal connection 9 of the rams 8 thereto are a pair of mutually inclined links 12, 13 which are pivotally connected at their lower ends at 32, 33 to respective chassis portions 2, 3. Further mutually inclined links 14 are pivotally connected from mid points or thereabouts at 34 of the first mentioned links 12, 13 to a common pivotal connection 15 with the carriage 7 in order to stabilise the latter. Such linkage is duplicated at each side of the vehicle, (see FIG. 2) and as shown in FIG. 1 the links 12, 13, 14 define a parallelogrammic link formation with the rams 8 acting substantially diagonally in relation to said formation.

The carriage 7 is shown movable by rollers 37 in guideways 36 in the rear chassis portion 3.

On retraction of the rams 8 the action of the links 12, 13 is to thrust the chassis portions 2, 3 away from one another in order to increase the wheelbase of the front and rear wheels 4, 5 to the maximum condition shown, the fully retracted position of the front wheels being indicated at 4a. Conversely on extension of the rams 8 the links 12, 13 are moved towards one another and likewise the chassis portions 2, 3 for reducing the wheelbase i.e., as the jib 10 is raised or luffed to the inclined position.

In addition to such action of varying the wheelbase with jib movement in the interest of greater stability of the vehicle according to the attitude of the jib 10, the linkage 12, 13, 14 supports the pivotally mounted jib 10 in relation to the chassis portions 2, 3. Furthermore the upright arrangement of the rams 8 and tie linkage 6 results in rapid operation of the jib 10 being obtainable from the horizontal to the almost upright position and vice versa.

The main body 10a of the jib 10 is shown provided with a winch 11 at its rear end which is preferably a hydraulic motor driven at 11a rope 16 from the winch 11 passing forwardly to a pulley 17 at the head 10d of the jib extension 10b from where the rope 16 passes about the pulley 19 of a pulley block or hook 39 and then rearwardly about a further head pulley 18 to an anchorage 16a at the rear end of the jib extension 10b. The arrangement is such that as the jib 10 is extended or retracted, compensation of the effective length of the rope 16 is obtained so that the position of the pulley block 39 in relation to the jib head 10d remains substantially unaltered during jib extension or retraction which thus does not effect the operation of the pulley block by the winch 11. The ram 100 operates the jib 10 for extension as indicated at 10c. (FIG. 4).

For travelling movement of the vehicle, the front wheels 4 are shown driven by hydraulic wheel motors 49 and the front wheels 4 are in-turnable for obtaining swivelling movement of the vehicle for jib slewing about a turn table or other pivotal mounting at the rear wheels 5, preferably by differential swivel mechanism as set forth in British Pat. No. 1,297,113, commonly owned herewith.

Referring to FIG. 3, steering of the front wheels 4 for travelling purposes is shown effected by a pair of hydraulic rams 40 acting from fixed structure of the forward chassis portion 2 on one end 43 of a double armed lever 41 pivotally mounted at 42, the other end of the lever 41 being pivotally connected at 44 to and between a pair of hydraulic rams 45 pivotally connected at 46 to swivel or king pin mounting 48 of the front wheel stub axles on the front axle beam 47.

Appropriate operation of the rams 40 effects steering movement of the wheels 4, the rams 45 remaining inoperative and serving as a track rod. However when in-turning of the front wheels 4 is required as at 4b, the rams 40 remain inoperative to lock the lever 41 from which the rams 45 extend to effect in-turning of the wheels 4 about the king pin mounting 48.

An internal combustion engine (not shown) is conveniently carried by the forward chassis portion 2 for driving one or more pumps in supplying hydraulic fluid under pressure to the wheel motors 49 and the various rams of the machine. The forward chassis portion also carries the driving and control position indicated by the cab 25.

When the jib or boom 10 is in the horizontal positon and is telescopically fully retracted, the arrangement can be such that it enables unhindered operation of a fork lift unit 20 (FIG. 5) to be effected at the forward end of the vehicle in the manner indicated at 20a, the unit 20 being pivotally carried at 21 at the front end of the forward chassis portion 2 for back and forth angular movement by ram operation 26 in engaging the forks 22 with a load and lifting the latter. Conversely when the fork lift attachment is retracted to its minimum height unhindered operation of the jib 10 is possible including forward telescopic extension in the horizontal position During operation of the jib 10 the forks 22 may be swung back to an inoperative position about transverse pivotal mounting 23 against the column 24 of the attachment. The fork lift unit 20 may be operated in any known or suitable manner.

With the jib 10 in the horizontal position shown the chassis 1 is fully extended for maximum wheelbase and stability of the vehicle for operation of the fork lift unit 20.

As will be appreciated from the foregoing the machine as shown in FIG. 5 is capable of carrying out a wide variety of load handling operations by appropriate operation of the crane jib 10 and/or the fork lift unit 20 either separately or in conjunction with one another.