Mobile crane
AssigneeRenner Manufacturing Company
InventorRichard F. Voelz
Life of this patent
Estimating the term…
Abstract
A straddle type mobile crane includes a steering system which allows two-wheel or four-wheel steering. A first steering cylinder is associated with each wheel for four-wheel operation and an additional cylinder is associated with each of a first pair of wheels for two-wheel steering. An interlock system has a first mode for four-wheel drive wherein each wheel is coupled to its associated first steering cylinder and a second mode wherein each wheel is uncoupled from each first cylinder and each of the first pair of wheels are coupled to one of the additional cylinders and the other pair of wheels are locked to the frame. A first control prevents operation of the interlock unless the wheels are in predetermined orientation and a second control maintains proper alignment of the wheels in all angular positions.
Claims25
A mobile crane having spaced apart first and second front wheel means and spaced apart first and second rear wheel means which are also spaced from said front wheel means,
- first and second steering means,
- first and second coupling means for coupling said first and second steering means to said first and second front wheel means, respectively,
- first and second connecting means each having a first mode for connecting said first and second steering means to a power source for turning said front wheels through a turning angle,
- third and fourth steering means respectively associated with said first and second front wheel means and fifth and sixth steering means associated with said first and second rear wheels, respectively,
- third and fourth coupling means for coupling said third and fourth steering means, respectively, to said first and second front wheel means and fifth and sixth coupling means for locking and unlocking said first and second rear wheel means, respectively, in a predetermined orientation, said fifth and sixth steering means are operable to turn the said rear wheel means through a turning angle when the same are unlocked,
- said first and second connecting means having a second mode wherein said third, fourth, fifth and sixth steering means are coupled to said power source for simultaneously turning said front and rear wheel means through the same turning angles.
A mobile crane having spaced apart first and second front wheel means and spaced apart first and second rear wheel means which are also spaced from said front wheel means,
- first and second steering means,
- first coupling means for coupling and uncoupling said first and second steering means to said first and second front wheel means, respectively,
- connecting means having a first mode for connecting said first and second steering means to a power source for turning said front wheels through a turning angle,
- third and fourth steering means respectively associated with said first and second front wheel means and fifth and sixth steering means coupled to said first and second rear wheels, respectively,
- second coupling means for coupling said third and fourth steering means, respectively, to said first and second front wheel means, and third coupling means for locking and unlocking said first and second rear wheel means in a predetermined orientation,
- said connecting means having a second mode wherein said second and third steering means are coupled to said power source for simultaneously turning said front and rear wheel means through the same turning angles.
A mobile crane having spaced apart first and second front wheel means and spaced apart first and second rear wheel means which are also spaced from said front wheel means,
- first and second hydraulic steering means respectively associated with said first and second front wheel means,
- third and fourth hydraulic steering means, respectively associated with said first and second rear wheel means,
- each said hydraulic steering means being operative to turn its responsive wheel means through turning angles, first selectively operable valve means for connecting each said hydraulic steering means to a source of hydraulic pressure and for delivering proportioned quantities of hydraulic fluids to each, said valve means having a first mode wherein said first and second hydraulic means are coupled to said source of hydraulic pressure for simultaneously turning said front wheel means through the same turning angles.
- first and second coupling means for coupling said third and fourth hydraulic steering means to said rear wheel means, respectively, and third and fourth coupling means for selectively locking and unlocking said rear wheel means in a predetermined orientation whereby when said rear wheels are unlocked, said third and fourth hydraulic steering means are operable to turn the same through a turning angle, said valve means having a second mode wherein said first, second, third and fourth hydraulic steering means are coupled to said source of hydraulic pressure for simultaneously turning said front and rear wheel means through the same turning angles,
- servo means connected to each of said wheel means and operative to produce electrical error signals functionally related to any deviation in the turning angle of any three of said wheel means from that of said fourth,
- and second valve means responsive to said error signals and coupled to the first valve means for adjusting the flow of hydraulic fluid to the hydraulic steering means of said three wheel means in a manner to reduce any such deviation.
A mobile crane having spaced apart first and second front wheel means and spaced apart first and second rear wheel means which are also spaced from said front wheel means,
- first and second steering means,
- first coupling means for simultaneously coupling said first and second steering means to said first and second front wheel means, respectively,
- connecting means having a first mode for connecting said first and second steering means to a power source for turning said front wheels through a turning angle,
- third and fourth steering means respectively associated with said first and second front wheel means and fifth and sixth steering means associated with said first and second rear wheels, respectively,
- second coupling means for simultaneously coupling said third and fourth steering means to said first and second front wheel means and third coupling means for simultaneously locking and unlocking said first and second rear wheel means in a predetermined orientation, said fifth and sixth steering means are operable to turn the said rear wheel means through a turning angle when the same are unlocked,
- said connecting means having a second mode wherein said third, fourth, fifth and sixth steering means are coupled to said power source for simultaneously turning said front and rear wheel means through the same turning angles.
Dependencies are inferred from the claim text.