US2220450A

US2220450A - Industrial truck

Info

Publication number: US2220450A
Application number: US241806A
Authority: US
Inventors: Roy C Howell
Original assignee: Individual
Current assignee: Individual
Priority date: 1938-11-22
Filing date: 1938-11-22
Publication date: 1940-11-05
Anticipated expiration: 1957-11-05

Description

Nov. 5 1940. R c HOWELL 2,220,450

INDUSTRIAL TRUCK Filed Nov. 22, 1938 4 Sheets-Sheet 1 INVENTOR ROY C. HOWELL ATTORNEY Nov. 5, 1940.. R. c. HOWELL INDUSTRIAL TRUCK 4 Sheets-Sheet 2 Filed Nov. 22, 1958 INVENTOR ROY C. HOWELL 5 4 O 0 0 O 8 O W 1 I P l I I l I l I I I .Ill llh i Q y h 9 W J 3 4 0 5 ATTORNEY Nov. 5, 1940. R. c. HOWELL INDUSTRIAL TRUCK Filed Nov. 22, 1938 4 Sheets-Sheet 3 o o 5% @n INVENTOR ROY C. HOWELL ATTORNEY Nov. 5, 1940. R. c. HOWELL INDUSTRIAL TRUCK 4 Sheets-Sheet 4 Filed Nov. 22. 1958 L L .E WM

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Patented Nov. 5, 1940 UNITED STATES INDUSTRIAL TRUCK Roy 0. Howell,

Iakewood, @liio Application November 22, 1938, Serial No. 241,806

8 Claims.

This invention relates to industrial trucks of the type used for hoisting and transporting loads on a lift platform mounted for vertical movement at the forward end of the truck frame.

To provide a high lift, industrial trucks have been'provided with telescopic standards which are extended as the platform is lifted. Such high lift trucks are, however, unsuitable for use in piling material in or removing material from boxcars or low ceilinged rooms of warehouses, because they require a clearance equal to the full height of the extended standards.

The present invention has for its object to provide a combination low lift and high lift truck having a telescopic standard which may be extended for high lifts, but which provided with a hoisting mechanism for the lift carriage by which the carriage may be lifted to the top of the standard whether the standard be extended or collapsed.

A further object is to provide a truck in which the lift carriage is operated by the movable section of the standard for high lifts and in which the lift carriage may be elevated to the top of the collapsed standard by the hoisting means.

A further object is to provide a simple and efiicient means for tilting the lift platform and elevating the same in tilted position.

With the above and other objects in view the invention may be said to comprise the truck as illustrated in the accompanying drawings hereinafter described and particularly set forth in the appended claims together with such variations and modifications thereof as will be apparent to one skilled in the art to which the invention appertains.

Reference should be had to the accompanying drawings forming a part of this specification, in which:

Figure 1 is a side elevation of a truck embodying the invention;

Fig. 2 is a fragmentary front elevation of the lower end of the guide standard upon which the lift platform is slidably mounted, viewed as indicated at 2-2 in Fig. 1;

Fig. 3 is a fragmentary side elevation of the forward end of the truck showing the lift platform in tilted position in full lines and in load pick-up position in dotted lines;

Fig. 4 is a diagrammatic view of the fluid pressure hoisting and tilting cylinders together with the fluid pressure supplying and controllin means;

Fig. 5 is a front elevation of the truck with portions of the lift carriage and the guide standard broken away and shown in section;

Fig. 6 is a vertical section indicated at line 6-6 of Fig. 5;

Fig. 7 is a detail sectional view on an enlarged scale showing the latch which controls the extension of the guide standard;

Fig. 8 is a side elevation of the trolling lever;

Fig. 9 is a top plan view of the guide standard hoisting mechanism;

Fig. 10 is a diagrammatic view showing the lift platform in its uppermost position with the guide standard unextended;

Fig. 11 is a diagrammatic view showing the lift platform in its uppermost position with the guide standard extended; and

Fig. 12 is a diagrammatic view of the lift platform in load-carrying position on a standard prolatch convided with cams for tilting the load lifting carriage as it is elevated.

In the accompanying drawings the invention is shown applied to an industrial truck having a frame I, a front axle 2 upon which traction wheels 3 are mounted, and rear steering wheels 4 mounted on forks 5 which have vertical spindles 6 journalled inthe frame. A laterally facing drivers seat I is provided on the frame and the usual steering column 8 and brake and clutch pedals 9 and ID are provided in front of the drivers seat. The truck is propelled by means of an engine mounted in a suitable housing II, the traction wheels 3 being driven through suitable driving connections in the housings l2. At the forward end thereof the frame I is provided with side plates l3 which are rigidly attached to the frame and extend forwardly between the wheels 3. Between the side plates l3 there is mounted a guide standard indicated generally by the numeral I 4 which is supported on the axle 2. A load lifting carriage I5 is mounted for vertical travel on the standard I 4, the carriage I5 being provided with a forwardly projecting load-carrying platform IS.

The standard I4 is an extensible standard consisting of a lower section attached to the truck frame and a movable section telescopically connected to the lower section. The lower section of the standard consists of a pair of inwardly facing channels l1 and the movable section consists of two outwardly facing channels l8, the flanges of which receive the flanges of the channel posts I! between them as best shown in Fig. 9. Suitable keys l9 are provided between the flanges of the channels I! and I8 to guide the channels 18 in cylinder 22 is attached at' its lower end to the {bearing member 20 and has a vertically movable c in front of the cylinder.

For hoisting the carriage" I5 and for extending .thestandards M, a hydraulic cylinder 22 is mounted between the channel posts IT. The

piston 23 which carries a sprocket 24 at its upper end. A sprocket chain '25 is connected by" an anchor bolt 26 to the bearing member and extends up over the sprocket 24 and downwardly The depending portion of the chain carries a lifting member 21 which is in the form of a hook to engage witha cross shaft 28 on the carriage l5. 7 The carriage l5 has a pair ofrearwardl'y extending arms 29 which extend 'rearwardly between the telescopically connected-channel bar of the standard. The'arms 28 of the carriage are connected by'the cross shaft 28 adjacent the lower edges of the arms and forwardly of'the standards |4. Above the shaft 28 the arms are their upper edges by a cross shaft'3l. The

shafts

28 and 3| project through the. 23 and carry rollers .32 and 33 which bear'against the front and rear sides of the channel bars l8. zThe..lifting member 21 has a flange 34 which,; in the'lowermost positionof theliftingmember, rests upon the top ofthe crossbar 2| which connects the lower ends of the channel :members l8 and the lifting member is adapted'to be connected to the cross bar 2| to lift the" channels l8 and extend the standard by Jmeans of .a latch 35 which is normally held in a position projecting beyond the rear face of the lifting member 21 so as to engage with the lower edge of the cross bar 2| when the lifting member is raised.

" member will be. retracted by engagement with thecrossbar 2| as the carriage |5.is lowered.

The latch member 35 is normally pressed rearwardly bymeans. of a spring 81 so that the latch member will normally snap to a position beneath the cross bar 2| when the carriage I5 reaches its lowermost position. The latch 35 normally connects the cross bar 2| to the lift member 21- so that when the piston 23 lselevated'the movable section of the standard is raised with the carriage l5. It-isdesirable, howevento extend the standard only for high lifts,and suitable means is providedfor rendering the latch 35 inoperativeto lift the movable section ofethe standard. The latch controlling means herein shown is a plunger 38 which is slidably mounted in a casing 38 immediately at the-rear of the cross bar 2|. The plunger 33 is normallyprojected forwardly beneath the cross bar 2| by means of. a'spring 40 in the casing 38. -spring 48 is stronger than the spring 31 of the latchsoi that when the lifting member 21 isin itslowermost position the latch 35 maybe held by the plunger 38 in a p sition clear-of the cross bar-2|. When theplunser 38 is projected-into engagementwith the latch 35, the latch 35 rides from the face. of the plunger. 33 onto-thefront face or the cross bar 2|.t0 per- -mit'the member 21 to move past thecroa its lowermost position the latch rides down the outer face 'of the cross bar 2| and onto the end face of the plunser 33.

Means is provided for retracting the plunger 38 in opposition to the spring 45 and forholding the plunger in retracted position to permit the latch 35 to engage the cross bar 2|. for causing the standard M to be extended. The plunger is retracted by means of aflexible cable 4| attached to the plunger 38 and extending to a lever 42 mounted on the frame I. The lever 42 is provided with apawl '43 which engages with a sector plate 44 to retain the lever 42 in the position in which the plunger 38 is retracted. When- .ever the pawl 43 is tripped the spring 48 returns 45 andhas a counterweight 41 attached thereto.-

The length of the chains 45 is such that when thecarriage I5 is lifted without extending the standard H, the counterweights 41 are adjacent the lower end of the standard when the carriage |5 is adjacent the upper end-of the standard.

When-thehoist cyiin'der' fl is operated with the lift member .21 disconnected from the movable -section;' of the standard, counterweights ,41 move from-aposition adjacent the top of posts l1 to a position. adjacent the lower end thereof as the carriage is elevated from lowermost position to a position adjacent theupper end of the posts I1.

When thecross bar -2| is connected by the latch 35 to the lifting member 21, the movable section of thelstandard is lifted with the carriage l5.

As the carriage is lifted by the lift. member 21 the sprockets 45 are elevated and the counterweights 41 engage with stop members 48 attached to posts |1 adjacent their upper ends. Each stop member 48 is inthe form of an angle bracket having apertures 48 through which a chain 45 extends. With the counterweights in engagement with the stop members 48, upward movement of the hoisting piston 23 will draw the chains 48 over the sprockets 45 and lift the car-.

riage |5 off the hook shaped lifting member 21, causing the carriage to move upwardly past the upper ends of the posts l1 and along the channels l8. The length of the chains .45 is such that when the movable section of thestandard is moved to its uppermost position the carriage I5 is lifted to adjacent the upper end-of the movable section as shown in Fig. 11. I i It is desirable-that the load carrying platform be'tilted .rearwardly to insure retention of the load during travel of the truck and during the elevating operation. Tilting of the carriage may be accomplished by pivotally mounting the standard l4 upon the axle'2.

As best shown in Fig. 6, the bearing member 25 is mounted to rock on the axle 2 and provided with a rearwardly extending arm 52 which is 'connectedto the piston 53 of a fluid pressure cylinder 54. The pivotal movement of the. standard. I4 is limitedlby means of pins58 attached to the channel posts l1 and extending through shortarcuate slots 5| in the side plates l3.

' As best shown in Fig. 4, of the drawings, liquid under pressure is applied to the

cylinders

22 and 54 by means-of a pump 55 which may be driven from the engine of the truck, the liquid passing throughinlet-pipe" and an outlet pipe 51, the

inlet and outlet pipes extending to a liquid reservoir 58, theout-let pipe 51 having a pressure limiting relief valve 51a adjacent the reservoir. A pipe 59 leading from the pump outlet pipe 51, extends to a valve casing 88 in which there is mounted a sliding spool valve 6| operated by lever 82. The valve 6| has spaced plungers 83, GI and providing chambers in the valve casing through which communication may be established between the pipe 59 or a return pipe 66 to the reservoir 58 with a pipe 61 leading to the cylinder 54. A

second pipe 68 leading from the pump outlet pipe 61 extends to a valve casing 69 which has a spool valve 10 operated by a lever II. The valve 10 hasspaced plungers I2, I3 and" which provide chambers in the valve casing for establishing communication between the pipe 68 or a return pipe 15 with a pipe 16 leading to the fluid pressure cylinder 22.

In the operation of the truck, as shown in Fig. 3, the platform It may be positioned in a horizontal position or in a slightly forwardly inclined position for loading and, after loading, may be tilted by means of the fluid pressure cylinder rearwardly, to a position such that there is no danger of the load falling off the platform.

A modified form of tilting device is shown in Fig. 12 in which the channels l8 are provided on the front and rear sides thereof with cam strips I1 and 18 which terminate a short distance above the lower end of the post. The lower ends of these strips are beveled as shown at 19 and 80, the beveled end 19 being somewhat below the beveled end 80, so that during the initial lifting movement of the carriage IS the

rollers

32 and 33 ride up the inclines 19 and B0 to force the rollers farther apart to tilt the carriage to the position shown in full lines of Fig. 12.

Furthermore, it is understood that the particular form of apparatus shown and described, and the particular procedure set forth, are presented for purposes of explanation and illustration and that various modification of said apparatus and procedure can be made without departing from my invention as defined in the appended claims.

What I claim is:

1. An industrial truck comprising a frame, an extensible guide standard comprising telescopically connected sections carried by the frame at the forward end thereof, one of said sections being attached to the truck and another being movable on the attached section, a load lifting carriage mounted for vertical movement on the standard, hoisting means, means for connectin said hoisting means to said carriage only to lift the same to the upper end of the unextended standard while said movable standard section remains stationary, means for connecting said hoisting means both to said carriage and to the movable section of the standard to simultaneously lift the movable section of the standard and carriage, and an auxiliary hoisting means operated by said movable section for lifting the carriage along the movable section during upward travel of the movable section.

2. An industrial truck comprising a frame, an extensible guide standard comprising telescopically connected sections carried by the frame at the forward end thereof, a load lifting carriage mounted for vertical movement on the standard, hoisting means, means for connecting said hoisting means to said carriage to lift the same to the upper end of the unextended standard, means operable when said carriage is in a lowered position for connecting a movable section of the standard to said hoisting means to extend the standard, and means operated by a movable section of the standard for moving the carriage upwardly along the movable section as the movable section is moved upwardly.

3. An industrial truck comprising a frame, a guide standard mounted on said frame, said standard comprising a lower section attached to said frame and a movable section telescopically connected to said lower section and movable from a'posltion in which its lower end is adjacent the bottom of the lower section to a position in which its lower end is adjacent the top of the lower section, a load lifting carriage mounted for vertical movement on the standard, a lifting memberengageable with said carriage and mounted on the lower standard section for movement from a position adjacent the lower end thereof to a position adjacent the top thereof, means for actuating said lifting member releasable means for connecting said movable standard section to said lifting member, and means operated by said movable standard section for lifting said ca?- riage out of engagement with said lifting member and moving the same upwardly past the lower section and along the movable section.

4. An industrial truck comprising a frame, a guide standard mounted on said frame, said standard comprising a lower section attached to said frame and a movable section telescopically connected to said lower section and movable from a position in which its lower end is adjacent the bottom of the lower section to a position in which its lower end is adjacent the top of the lower section, a load lifting carriage mounted for vertical movement on the standard, a lifting member engageable with said carriage and mounted on the lower standard section for movement from a position adjacent the lower end thereof'to a position adjacent the top thereof, means for actuating said lifting member, releasable means for connecting said movable standard section to said lifting member, and an auxiliary carriage hoisting means comprising a guide member carried by said movable section, a flexible hoisting member running over said guide and attached at one end to said carriage, a counterweight attached to the opposite end of said hoisting member and a stop for limiting the upward movement of said counterweight.

5. An industrial truck having a frame, a standard mounted on said frame, said standard comprising a lower section attached to the frame and a movable section telescopically connected with the lower section, a load lifting carriage mounted for travel on said standard, means for hoisting said carriage comprising a cylinder carried by the lower section of the standard and having a vertically movable piston, a sprocket carried by said piston at its upper end, a chain attached to the lower section of the standard at one end extending over said sprocket and having a hook engageable with said carriage at its opposite end, a second sprocket at the upper end of said movable standard section, a chain attached movable standard section to said first mentioned chain.

6. An industrial truck comprising a frame, a front axle upon which traction wheels are mounted and rear steering wheels, a standard having its lower end pivotally mounted on said axle between said traction wheels, said standard comprising telescopically connected sections, a load lifting carriage mounted for vertical movement on said standard, fluid pressure operated means mounted on the standard for extending said standard and lifting said carriage along the standard, fluid pressure means for swinging said standard rearwardly on its pivot to tilt said carriage, and stop members on the standard for limiting the swinging movements of the standard.

7. An industrial truck comprising 'a frame, a standard attached to the forward end of said frame, said standard comprising a section attached to the frame an a movable section exteriorly engaging said fixed section, a load lifting carriage having vertically ofiset rollers engaging the front and rear sides of said movable section, hoisting means, means for connecting said hoisting means to said movable standard section,

means connecting said carriage to said movable standard section-for movement in unison with the movable section, and auxiliary hoisting means carried by said movable section and operable after movable section has been lifted to a predetermined height to lift said carriage at a speed greater than that of the movable section, thereby causing the carriage to travel upwardly upon the vertically moving standard section.

8. An industrial truck comprising a frame, a standard attached to the forward end of said frame, said standard comprising a section attached to the frame and a movable section exteriorly engaging said fixed section, a load lifting carriage having vertically offset rollers engaging the front and rear sides of said movable section, hoisting means, means for connecting said hoisting means to said carriage and to said movable standard section, auxiliary hoisting means carried by said movable section and operable upon a predetermined movement of said section to lift said carriage at an increased speed, and earns carried by said movable section in the path of said rollers for tilting said carriage.

ROY C. HOWELL.