US2114262A

US2114262A - Ladder truck

Info

Publication number: US2114262A
Authority: US
Inventors: Homer M Havens
Original assignee: Seagrave Corp
Current assignee: Seagrave Corp
Priority date: 1935-04-23
Filing date: 1935-04-23
Publication date: 1938-04-12
Anticipated expiration: 1955-04-12

Description

pril 12, 1938. H. M. HAvENs LADDER TRUCK Filed April 25, 1955 4 Sheets-Sheet l Srmentor HUMER M.HAVENS f gli (Ittorneg 5 April l2, 1938' H. M. HAVENS 2,114,262

LADDER TRUCK Filed April 25, 1955 4 sheets-sheet 2 76 (f o l m 7s 73 El 50 7g f1.5 f o u l 1| O O o www I6 I l l5 nnenfor m93' 3 HUMER NLHAVENS (Ittorneg 5 April 12, 193s. H M, HAVENS 2,114,262

LADDER TRUCK Filed April 23, 1935 4 Sheets-Sheet 3 Srmentor ynMER M.HAv ENs Bg @M (Ittorneg .1

April 12, 1938. H. M HAVENS 2,114,262

LADDER TRUCK Filed April 25, 1935 4 Sheets-Sheet 4 mnentor HUMER M.HAVENS y Wx (lttorneg J Patented Apr. l2, 1938 UNITED- STATESI PATENT oFFicE LADDER Tanon Homer M. Havens, Columbus, Ohio, assignor to The Seamve Comration, Columbus, Ohio, a

corporation o f Michigan l Application April 23, 1935, Serial No. 17,835

SCiaims.

'This invention relates to aerial ladders such as used by the fire departments of municipalities to aid in extinguishing res and rescuing persons and property from burning buildings.

Such ladders are now commonly transported by engine driven trucks.

Because such ladders and the, essential parts thereof are necessarily heavy and bulky and therefore dimcult to quickly move, the primary object of the invention is to provide improvements in details of construction whereby their operations are facilitated and speede'd by the application of the power used to transport the ladder and thereby relieve the ladder men of the physical exertion heretofore necessary in the handling oi' such parts. 'Ihe particular object of the invention is to provide improved means whereby flexible hose for conducting pressures is dispensed with so that the turn table in such structure may be rotated in either 'direction as much as desired. Other objects will appear from the disclosure herein.

In the accompanying drawings showing one exempliiication of the invention- 1 Figure 1 is a general view in sideelevation and partly diagrammatic onv a relatively small scale illustrating a fraction of a truck with a turntable thereon supporting the ladder and the power applying means whereby the ladder is raised and lowered.

Fig. 2 is a detail on a largergscale partly in` section and elevation illustrating the mounting and connection of the parts for applying power to raise and lower the ladder.

Fig. 3 is a detail partly in section and showing .means to operate the ladder extensions.

Fig. 4 is a detail view partly in elevation and partly in section of the means for rotating the turn-table and for hoisting the ladder extensions. f

Fig. 5 is a detail view in rear elevation of means for locking the turn-table in the position to which it'may be rotated.

Fig. 6 is a plan view with parts in section of the means for controlling the operation of the ladder. i

Fig, 'I is a detail plan and sectional view of the operating and controlling means for the hoisting of the ladder extensions.

Fig. 8 is detail view of the base of the ladder to show portions of the means for hunting the raising of the ladder.

In the views I6 designates the truck bed of the chassis and I I the. turn-table which is supported centrally to be rotated on said truck bed. The turn-table II is`engagedand supported at its rim on the truck bed by a suitable "track I3 withv ball bearings; and at the center of the turn-table is secured la double valve structure supported on a ring Il in which latter is supported a non-rotatable casing I5. Said non-rotatable casing is provided with a threaded intake I6 having an upwardvpassage I6, the upper end of which communicates with the two valve casings I'I and I6 for the purpose of supplying oil under pressure to raise and lower the ladder and also to turn a winding drumy to raiseand lower the ladder extensions.y The casing I5is provided with a distinct discharge downward passage I9SL surrounding said upward passage and leading to a threaded opening I9 for the return of the oil to the tank.

' 2iidesignates the main ladder, it being pivoted at its base on the opposite ends of a shaft 2l ljournaled in brackets 2|L rising from the Lturn table. 'Ihe main ladder carries extensions 2lim andlib.

At each of its opposite sides the ladder is connected 'with the turn-table by a piston rod 22 having piston 22EL working in a cylinder 23, said piston rod being pivoted to the ladder and said l cylinder pivoted to the turn-table so that wh'en liquid (preferably oil) is forced into the cylinder at the lower side of the piston the ladder is raised on the shaft ends 2|, and when liquid is forced into the cylinder through a by-pass 24 to the upper side of the piston the ladder is lowered. Each of the two valve, casings II-and I 8 contains a double slide valve, one to control the ow of oil in

pipes

25 and 26. The pipe 25 andits two

branches

25 and 25b conduct the oil tothecylinder 2l for raising the ladder and pipe 26 and its two branches 26'l and 26b conduct oil to the bypass 24 for lowering theladder. The two heads of each of said valves are mounted on the opposite ends of a tube as at 21 carried by the stem of the valve, said tube being closed between the heads, but -perforated as shown at 2lb at its opposite projecting ends to permit the flow of oil through thetube between the chamber portions of the casing beyond the valve heads.

The stems of

valves

21 and 28 are each shifted by manual operation at the housing 41 to open and close the ports to said

pipes

25 and 26, but means are provided as hereinafter described for vautomatically closing them upon predetermined operation.

The valve casings I1 and I8 and ring bearing the discharge I9 of the casing I5 communicates with a storage tank 34 that in turn is connected with the intake ofthe pump 33. The pump 33 is of the usual rotating type and is operated by the power take off shaft 35 from the engine 36 that propels the truck carrying the ladder to the site of a re. The engine of the truck referred to and the power take off are not shown in detail because they are of ordinary and well known construction. In the pressure delivering operation the same liquid (the oil) is repeatedly used to,

raise the ladder or project the ladder extensions because after removing the oil from the tank 34 to perform these operations it is returned to said tank through the discharge I9 of the stationary casing I5.

The valve casing I8 has connected communicatingly with it pipes 31 and 38 for the purpose of conducting oil under pressure to a fluid motor for raising or lowering the ladder-extensions 2lia and 2Gb, said extensions being connected in the usual manner for their concurrent movement. Said extensions are operated by means of two cables (one shown at 39) connected to opposite ends of the drum to wind in opposite directions, one of said cables to draw up the extensions and the other to pull down said extensions according -to th direction of rotation of the drum.

The pipe 38 leads the oil under pressure from the control valve casing I8 to a port 38a (shown in broken lines Fig. 3) of a fluid motor 5I, and after operating said motor to the extent desired the oil is returned to said valve casing I8 by means of the pipe 31 connected with the port 31B of said motor 5I. Said operation occurs only when the pressure intake and exhaust of the casing I8 are utilized.

Connected with the shaft 2l of the cable winding drum 58 is a worm gear 40 driven by a worm 4I on the shaft of the motor 5I. By reason of this construction said motor 5I can be driven to rotate the cable in the proper direction to cause the extending or drawing down of the ladder extensions. Change of rotation of the motor and winding drum isaccomplished by shifting the valve of the casing I8 to cause the oil under pressure to flow through the pipe 31 or 38 according to the direction of rotation necessary to achieve the operation desired. The two points for attaching the cables to simultaneously wind and unwind them are indicated at 50a and 58".

The two valve casings I1 and I8 have between them at 42 an intake common to them for the pumped oil, said intake being connected by passages with the intake I8 of the casing I5.

When oil is being pumped to raise the ladder the residual oil in the cylinder 23 above the piston therein is returned or exhausted to the tank 33 through the tube 21.1 connecting the valve heads of the valve casing I1 through outlet I9 and down passage I9EL and outlet I9 in the casing I5. And when the piston is shifted to cause the pressure to pass through the by pass I6 in lowering the ladder the oil below the piston in the cylinder exhausts directly through the outlet 44 and through the down passages in the casing I5 to the tank 34. The operation is the same'when raising and lowering the ladder extensions but is controlled by the valve of similar` construction in casing I8. By reason of this construction theactuating medium'is saved for repeated use, and at the same time provides a construction whereby the turn table can be turned unrestrictedly in either direction at will.

The

stems

21 and 28 for the valves in the casings I1 and I8 are forked at their outer ends to receive a link 21d with one of two crank arms on a shaft 45 op rated by a handle 46 at the top of housing 41 containing the controlling means` whereby said valves can be shifted to initially direct the flow of the oil pressure for the opera.-

Ation of raising the ladder and its extensions, but

it is desirable that said rising movement be automatically limited. For this purpose, and in the case of the ladder raising, the stem 21 is provided with a collar 21c engaged by one arm 48 of a bell-crank lever 49 pivoted on the turntable, the other arm of said lever being actuated by a collar 52 on a rod 53 connected with one end of alink 54 having its other end connected with an ear 55 on the base of the ladder so that when the ladder has been raised to the predevtermined limit the oil pressure is cut off provided the valve stem has not been earlier manually shifted. And likewise in the case of the ladder-extension-raising-means the valve stem 28 is provided with a collar 28c engaged by one end of a bell-crank lever pivoted on the turntable, the other arm of said lever being actuated by a collar 6I on a rack rod 62 riding on a pinion 63 on the shaft of a large worm gear 64 driven by a worm 65 on the shaft of the 'motor that turns the ladder-extension hoisting drum'50, so that when the ladder extensions have been extended to the predetermined limit provided the valve in the casing I8 has not been earlier manually shifted to cut off the flow of the oil pressure. It will be observed that the flow of pressure in the valve casing I1 or I8 can be arrested by moving the valves therein to neutral position and the ladder or extensions thereof supported in any position to which moved by reason of the fluid entrapped in the cylinders or motor.

The means for rotating the turn-table includes the followingz-The supporting track I3 having its rim provided with gear teeth engaged by an intermediate gear wheel 10 so that in turn it is engaged by a pinion 1I secured on the lower end of a vertical shaft 12 extended upward in the housing 41 secured on a base on the turn-table. The upper end of said shaft 12 has secured to it a bevel gear 14 that is engaged by a pinion secured on a shaft- 15 turned by a hand wheel 16 so that by turning said wheel 16 in one direction or the other the turn-table canbe turned to the position desired and suitable for pointing the ladder and its extensions in the direction desired notwithstanding the position of the truck carrying the apparatus; When the ladder has been pointed, as desired, the shaft of the hand wheel 16 can be locked to prevent any movement of the table by means of a clevis 11 on said shaft drawn tightly around said shaft by a cam 18 connected with a bolt and a handle operating on the clevis to draw the free ends thereof together into pinching engagement with said shaft.

At 88 is an ordinary relief chamber to take care of excess pressure in the oil system in case the ladder meets an obstruction either in raising 1. In a truck ladder, a turn-table mounted o i the truck, a ladder pivoted on the turn-table, fluid pressure actuated means for raising and lowering the ladder, a valve casingsupported on the turn-table to rotate therewith and communicating with said means for raising and lowering the ladder, said valve casinghaving an intake and a discharge passage and containing a valve to control the application of fluid pressure to said means for raising and lowering the ladder, a pressure uid conducting casing supported stationarily on the truck coaxially with the axis of rotation of said turn table, said stationary casing having a fluid pressure intake and discharge passage distinct `from each other communicating in all positions of the turn-table with corresponding passages in said control valve casing, a tank into which the outlet of said stationary casing discharges, and a pump for creating fluid pressure through the intake of said stationary casing to the said valve casing and ladder raising and lowering means.

2. In a truck ladder, a turn-table mounted on the truck, a ladder pivoted on the turn-table, fluid pressure actuated means for raising and lowering the ladder, a valve casing supported on the turn-table to rotate therewith and communicating with said means for raising and lowering the ladder., said valve casing having an intakev and a discharge passage and containing a valve to control the application of iiuid pressure to said means for raising and lowering the ladder, a pressure fluid conducting casing supported stationarily on 4the truck coaxially with the axis of rotation of said turn-table, said stationary casing having a fluid pressure intake and discharge passage distinct from each other communicating in all positions of the turn-table with corresponding passages in said control valve casing, a. tank into which the outlet oi' said stationary casing discharges, a pump for creating pressure through the intake of said stationary casing, and a conductor for 'feeding the pressure medium from said tank to said pump.

3. In a ladder truck, a turn-table mounted on the truck and supporting the main ladder and an extension thereon, a fluid pressure conducting casing supported stationarily on the truck below said turn-table, said casing having an inlet and an outlet passage distinct from each other in respect to a pressure supply means, two valve casings supported upon said turn-table to rotate therewith, said valve casings having concentric communication in all positions of the turn table with the inlet and outlet passages of said stationary casing, iiuid pressure actuated means communicatingly connected with said valve casings for raising and lowering the main ladder, and independently operable fluid pressure means communicatingly connected with said valve casings to extend or retract the ladder extension, and valve means in said valve casings for controlling at will the application of fluid pressure to said main ladder and its extension.

4. In a ladder truck, a turn-table mounted on the truck and supporting the main ladder and an extension thereon, a uid pressure conducting casing supported stationarily on the truck beiowsaid turn-table, said casing having an inlet and an outlet passage in respect to a pressure supply means distinct from each other, two valve \casings supported upon said turn-table, s aid valve casings swiveled to said stationary pressure conducting casing and having concentric communication with the inlet and outlet passages thereof, tluid pressure actuated means communicatingly connected with said valve casings for raising and lowering the main ladder, andindependently operable iluid pressure means communicatingly connected with said valve casings to extend or retract the ladder extension, and valve means in s aid valve casings for controlling at will the application of iiuid pressure to saidl main ladder and its extension.

5.v In a ladder truck. a turn-table mounted on the truck and supporting the main ladderhaiid an extension thereon, fluid pressure supplying and actuated means for said ladder and extension including ya fluid pressure conducting casing supported stationarily on the truck below said turntable, said casing having an inlet and an outlet passage distinct from each other in respect to a pressure supply means, two valve casings supported upon said turn-table, said valve'casings swiveled to said stationary pressure conducting casing and having concentric communication with the inlet and outlet passages thereof, means for automatically limiting the application of pressure to said fluid pressure actuated means communicatingly connected with said valve casings for raising and lowering the main ladder,

` and independently operable fluid pressure applying means communicatingly connected with said valve casings to extend or retract the ladder f extension at will. 6. In a ladder truck, a turn-table mounted on the truck and supporting the main ladder and an extension thereon, a fluid pressure conducting casing supported stationarily on the truck below said turn-table, said casing having an inlet and an' outlet passage distinct from each other in respect to a pressure supply means, two valve casings supported upon said turn-table, said valve casings swiveled to said stationary pressure-conducting casing and having concentric communication with the inlet and outlet passages thereof, packing means at the swiveling junction of said valve casings and pressure conducting casing for preventing leakage of pressure iiuid to the atmosphere and from one passage to the other, fluid pressure actuated means communicatlngly connected with one of said valve casings for raising and lowering the main ladder, and independently operable uid pressure means communicatingly connected with theV other of said valve casings to extend or retract the ladder extension, and valve means in said valve casings for controlling at will the application of fluid pressure to said main ladder and its extension.

7. In a ladder truck, a turn-table mounted on the truck and supporting the main ladder and an extension thereon, fluid pressure actuatable means for raising and lowering the main ladder and independently operable iiuid pressure actuatable means including a fluid motor and gearing means actuated thereby for extending and retracting the ladder extension, two valve casings and means therein and connected therewith for controlling at will the application vof fluid pressure to each of said uid pressure actuatable means, a iiuid pressure conducting casing supported stationarily on the truck, said casings having iluid pressure'inlet and outlet passages dissage distinct from each other in respect to a pressure supply means, two valve casings supported upon the turn-table, said valve casings swiveled to said stationary pressure conducting casing and having coaxial communication with thc inlet and outlet passages thereof, means for controlling the application of pressure to said main and extension ladder, and means for automatically limiting the application of pressure to the extension ladder.

HOMER M. HAVENS.