Patent GB-525763-A (GB)
Title: Improvements in and relating to motor vehicles, in particular motor turntable ladders, provided with supporting spindles
IPC: B60S9/08
Filed: 1939-02-28
Abstract: 525,763. Fire escapes. KLOCKNER-HUMBOLDT-DEUTZ AKT.-GES. Feb. 28, 1939, Nos. 6565 and 6566. Convention dates, March 1, 1938, and April 29, 1938. [Class 47 (i)] [Also in Group XXXI] In a motor vehicle, particularly one carrying a turntable ladder, whereon jack - like frame steadying members are adapted to be lowered and raised independently of the engine drive and which may be lowered when the engine is running, reciprocal locking means are provided to prevent the jacks being lowered while the driving gear is operable and, vice versa, to prevent the driving gear being operated until all the jacks have been raised into their travelling position. Further inter-locking means may also be provided between the jack and gear operating means and means respectively for locking the vehicle suspension springs and erecting the ladder. In the form shown in Fig. 1, jack-like frame supporting members 5 with bases 6 are normally retained in the raised position in casings 4 by locking bolts 10, dropping to the ground by gravity when released and being raised again by rotation of handles 7. The bolts 10 locking the respective jacks are carried by arms 11 connected by a rod 12 and are released by depression of an operating lever 8. Release is however prevented when the vehicle driving control lever 9 is in the operative position as shown, by a projection 16 on a rod 15 coupled to the lever 9 which obstructs movement of a bell crank lever 13 pivoted to the connecting rod 12, this obstruction being removed when the lever 9 is shifted to its inoperative position. When the jacks are released levers 18, engaging recessed parts 19 thereof, are rocked against the pressure of springs 17 and through bell cranks 21 raise a common bolt 24 against a spring 23 to obstruct the return of the rod 15, thus preventing operation of the lever 9 until all the jacks have been restored to their raised positions. In the modification shown in Figs. 2 and 4, in addition to interlocking between the driving gear control lever 9 and the jack operating means further interlocking is provided between these controls and the control 46 for the ladder erecting gear' and means 39 for connecting the wheel axle 2 directly to the vehicle frame 1. In this form, the jack members 5, which rotate as they descend, are normally secured in the raised position, Fig. 2, by spring pressed plungers 10 each engaging a hole in a disc 25 secured to a jack member. To release the jacks, the operating lever 8 is depressed causing 'bell crank arms 11 to raise the plungers by their heads 27, the bell cranks being connected by a rod 12 stressed by a spring 32. Release cannot however be effected until the driving control lever 9 is moved to withdraw a locking arm 16 from engagement with a slot 31 in a segmental disc 30 integral with the shaft of one of the bell cranks 11, whereafter the arm 16 rides on the periphery of the segment to prevent operation of the lever 9. Before the jacks can be released it is also necessary to engage the pivoted locking member 39 with the wheel axle 2, this operation being effected through, linkwork 40, 41, 42 either by rocking a hand. lever. 43 or detaching a hose reel 44. Until this is done, the arm 51 of one of the bell cranks 11 is obstructed by an arm 48 on a shaft 49 rocked by movement of the lever 43 in the manner described in Specification 505,058. In the travelling condition, Fig. 2, the ladder erecting control means 46 is also locked by a plunger 45 connected to a bell crank lever 35, 37 maintained in a raised position by a projection 34 on the bell crank arm 35 riding on the periphery of a pivoted plate 33 movable with the connecting rod 12, the other arm 37 of the bell crank being in engagement with a stop 38 on the axle clamp 39. Thus when the lever 9 has been rocked to disengage the drive, and the obstructing arm 48 removed by bringing the clamp 39 into engagement with the axle 2, the jacks may be released by depressing the arm 8. When the arm 8 is released and after the jacks have dropped, the plungers 10 and bell cranks 11 under the stress of springs 26 take up the final position shown in Fig. 4. the plate 33 thereby being rocked to release the locking plunger 45, allowing the ladder to be erected. In the return movements, the jacks are raised by rotation individually, as shown in Fig. 4, the plate 25 pushing the plunger 10 before it until the hole in the plate comes into alignment with the plunger. After all the jacks have been raised, the lever 9 still cannot be operated until the plate 33 has been freed from the stop 34 by raising the locking plunger either, directly by means of a handlever 47 or by disengaging the axle clamp 39. The lever 47 is provided to enable the vehicle to be moved with the axle clamp in engagement in cases in which the erected ladder cannot be retracted owing to damage.