US2034306A

US2034306A - Dump truck

Info

Publication number: US2034306A
Application number: US9027A
Authority: US
Inventors: Elbert W Lowdermilk
Original assignee: Individual
Current assignee: Individual
Priority date: 1935-03-02
Filing date: 1935-03-02
Publication date: 1936-03-17
Anticipated expiration: 1953-03-17

Description

March17, 1936. w LQWDEfQMILK Z,U34,306

DUMP TRUCK Filed March 2, 1935 2 sheets-sheet 1 INVENT OR.

ATTORNEY.

March 17, 1936. E, w, LOWDIERIMILK 2,934,306

DUMP TRUC K Filed March 2, 1935 2 sheets she et 2 um 'ulml Ell Patented Mar. 17, 1936 UNITED STATES ATENT OFFICE DUMZP TRUCK Elbert W. Lowdermilk, Denver, 0010. Application March 2, 1935, Serial No. 9,027

4 Claims.

This invention relates to a dump truck and has for its principal object the provision of a dump construction, which will elevate the dump body to an exceedingly high elevation; which can be operable from the usual truck Winch; which will require a minimum of power to elevate a maximum load; which will eliminate all projecting posts, hoists, etc.; and which will rapidly raise and lower the body or lock the same in any desired position.

Another object of the invention is to so construct the device that a series of different leverages will be employed; so that a minimum of power will be required to start a heavy load, carry it through the first heavy lifting stages; and thence rapidly through the final lighter lifting stages.

A further object of the invention is to provide a winch operating dump body which will not interfere with the use of the winch for hoisting operating derrick or other purposes.

Other objects and advantages reside in the detail construction of the invention, which is designed for simplicity, economy, and efficiency. These will become more apparent from the following description.

In the following detailed description of the invention reference is. had to the accompanying drawings which form a part hereof. Like numerals refer to like parts in all views of the drawings and throughout the description.

In the drawings:

Fig. 1 is a side elevation of the improved dump truck illustrating it in the partially elevated position.

Fig. 2- is an enlarged fragmentary side elevation illustrating the bed starting to elevate.

Fig. 3 is a longitudinal section through the preferred form of winch employed with the invention.

Fig. 4 is a fragmentary side elevation illustrating the bed in the full elevated position.

Fig. 5 is a similar view illustrating the bed in the down position.

Fig. 6 is a detail perspective view illustrating the cable connections to the winch.

In the drawings: a typical truck chassis is indicated at I!) supported upon the usual wheels I and provided with the usual drivers cab I2, engine hood l3 and bed I4. The bed I4 is pivoted to the rear of the chassis l9 upon a suitable hinge bolt 49. At the rear of the cab I2 is a winch l5 which may be any of the usual truck winches, but is preferably of a special design, as shown in Fig. 3.

The winch illustrated in Fig. 3 comprises a tubular winch shaft l6 driven from suitable worm drive gears enclosed in a housing IT. The worm drive may be connected with the engine drive shaft through a chain as is usual in truck winches. The winch shaft is supported in a bearing I8 at one extremity and in the winch housing IT at its other extremity and terminates in a fixed spool or nigger head 50.

Mounted upon the winch shaft are two side dumping spools I 9 and 20, positioned at each side of a main spool 2|. All of the spools are normally free to rotate upon the winch shaft l6. A first sliding gear 22 is mounted on the winch shaft within the spool l9, and a second sliding gear 23 is mounted on the winch shaft between the spools 20 and 2|. The first gear 22 may be brought into mesh with an internal gear 24 on the interior of the spool ill. The second gear 23 may be selectively brought into mesh with an internal gear 25 on the main spool 2| or an internal gear 26 on the side spool 20.

The two gears 22 and 23 may be moved axially by means of a slide rod 21 which extends into the hollow shaft l6 and connects by means of suitable spider arms 28 with the gears. The spider arms 28 slide in longitudinal slots formed in the wall of the tubular winch shaft IS. The slide rod is operated from an operating lever 29 which is connected to the slide rod 21 and fulcrumed in a bracket 39 on the support of the bearing l8. It is preferred to extend the operating lever 29 to a point within the reach of the operator in the cab I2.

It can be readily seen that as the operating lever 29 is swung inwardly (to the right in Fig. 3) it will cause the sliding gears 22 and 23 to lock the side spools l9 and 29 to the winch shaft Hi. When swung outwardly, it will cause the sliding gear 23 to lock the main spool 2| to the winch shaft. When in between these two positions, none of the spools will be locked to the shaft, but will be free to rotate thereon.

The side spools 9 and 20 are formed with suitable brake drums 3| and 32 against which brake bands 33 and 92 act. The main spool 2| is provided with suitable brake drums 35 against which brake bands 39 act.

The dumping operation is accomplished by means of the side spools l9 and 20. The dumping mechanism consists of a pair of similar toggle arms 3? hinged below and at each side of the forward extremity of the bed l4, and terminating in a horizontal roller shaft 38. A pair of sliding arms 39 extend forwardly and downwardly from the roller shaft 38 at each side of the chassis I. These sliding arms are formed with elongated slots 40 in their forward extremities, through which guide bolts 4| pass. The bolts 4| are permanently fixed to the chassis |0.

The roller shaft 38 extends across the chassis |0,-connecting the opposite pairs of

levers

31 and 48. This shaft carries a series of sheave wheels 42 between the arms 31 and a roller 43 at each extremity between each pair of

arms

31 and 39. A jack shaft 5| extends laterally across the chassis ahead of the roller shaft 38 and carries a second series of sheave wheels 52. An equalizing pulley 45 is mounted below the winch l5. An endless cable 44 is trained from each side spool of the winch rearwardly about the sheaves 42, thence forwardly about the sheaves V 52 and around the equalizing pulley 53.

The side members of the chassis are formed with top track members 46, the rearward extremities of which are inclined to form an inclined track 41. 'This track is so positioned that when the sliding arms 39 are at their rearmost positions, with respect to the slots 4|], the rollers 43 will be at the bottom of the inclined tracks 41. Beneath the forward extremity of the bed I4 is a cable roller 48, which, when the bed is down, rests upon the cables 44.

Let us assume that the bed I4 is in the horizontalposition of Fig. 5, and that it is desired to dump the contents thereof. The operator swings the operating lever 29 to the right so as to engage the winch with the side spools l9 and 20. He then starts to reel in the cable 44. The first tightening of the cable acts to lift the sheave wheel 48 directl upward and start the initial dumping movement of the bed, as shown in Fig. 2. The tightening cable then acts to draw the roller shaft 38 toward the winch. This causes the rollers 43 to travel upwardly on the inclined tracks 42 so as to continue the upward movement of the bed and straighten the toggle of the

arms

31 and 39. As the rollers move forwardly, the sliding arms 39 will also move forwardly until the extremities of the guide slots 40 reach the guide bolts 4|. At this point, the rollers 43 will have reached the top of the inclined tracks 41. From then on, the action is a simple toggle action between the

levers

31 and 39. The tightening cable will tend to straighten these levers and.

force the bed upwardly to the position of Fig. 5.

The bed may then be locked in the elevated position by means of the

brake bands

33 and 34, the side spools can be released from the winch .1 shaft, the winch clutch released and the truck started; The bed can then be lowered as desired by releasing the

brake bands

33 and 34.

The brake bands can be operated in any suitable way, such as from brake lever shafts 5| and 52 operated from suitable brake levers convenient to the driver.

The dumping mechanism can be operated from the ordinary truck-winch by simply training the cable 44 over the ordinary winch spool. This necessitates disconnecting the cable from the dumping mechanism when it is desired to use the winch for other purposes; With the winch of Fig. 3, however, the center spool 2| can be used for the usual winch purposes without interfering with the use of the side spools for dumping operations.

If desired, space could be conserved by placing the winch spools below the drivers seat in the cab |2. Thus, enabling the entire chassis to be used for bed purposes. 7

It is desired to call particular attention to the fact that it is always difilcult to start the movement of a pair of closed toggle arms. Therefore it would require excessive power to cause the cable to pull directly upon the roller shaft 38 to obtain the initial lift. In this invention, this excessive power requirement is avoided, first, by allowing the tightening cable to lift directly on the front of the bed, through the roller 48; second, by allowing the toggle arms to slide forward while the rollers travel up the inclined tracks 41. After this first movement is started, it is comparatively easy for the cable to straighten the toggle arms for the final lift. By bringing the cable about the two series of sheaves 42 and 52, a leverage is also obtained to assist the raising of the bed.

The equalizing pulley 45 acts to equalize the strain in the cable 44 and to cause the cable to lift equally at both sides of the chassis. It would be practically impossible to obtain an equal lift at both sides with two independent cables since it would be impossible to start reeling both of them simultaneously and. to retain them at equal lengths.

While a specific form of the improvement has been described and illustrated herein, it is desired to be understood that the same may be varied,

within the scope of the appended claims, without departing from the spirit of the invention. Having thus described the invention, what is claimed and desired secured by Letters Patent 1. Means for dumping a hinged truck body comprising: a chassis; a body hinged at its rear extremity to said chassis; a first pair of toggle arms hinged to said chassis; beneath the forward extremity of said body; a second pair of toggle arms hinged to said first pair and extending upwardly therefrom to a connection with said body; a winch supported on said chassis; a cable connecting said winch with the hinge point between said arms so as to pull the latter to a straight position to elevate said body; rollers positioned at the hinge points of said toggle arms and inclined planes carried by said chassis beneath said rollers to impart the initial movement to said body as said cable tightens, said toggle armsbeing arranged to allow a limited preliminary movement for the actuation of said rollers.

2. In a truck body having a chassis and a dumping body hinged adjacent the rear extremity of said chassis; means for lifting the forward extremity of said body comprising: a. first pair of toggle arms hinged to each side of the forward exrearward thereunder; a roller shaft extending between the rearward extremities of said arms; a cable wheel mounted on said roller shaft between said arms; a second pair of toggle arms mounted at their rearward extremities on said roller shaft and extending normally forward therefrom; guide members secured to each side of said chassis, said second pair of arms being slotted to pass over said guide members; a winch mounted on said chassis; a cable extending rearwardly from said winch about said cable wheel and forwardly to a connection with said chassis, said body normally resting upon said cable when in the lowered position.

3. In a truck body having a chassis and a dumping body hinged adjacent the rear extremity of said chassis; means for lifting the forward extremity of said body comprising: a first pair of toggle arms hinged to. each side of the forward extremity of said body and extending normally rearward thereunder; a roller shaft extending between the rearward extremities of said arms; a cable wheel mounted on said roller shaft between said arms; a second pair of toggle arms mounted at their rearward extremities on said roller shaft and extending normally forward therefrom; guide members secured to each side of said chassis, said second pair of arms being slotted to pass over said guide members; rollers mounted on each extremity of said roller shaft; inclined surfaces on said chassis below said rollers, said surfaces being positioned so that as said rollers travel therealong, said slots will move along said guide members; a winch mounted on said chassis; and a cable extending from said winch to said cable wheel so as to draw said roller shaft forwardly.

4. A dump truck construction comprising: a chassis; a dump body hinged adjacent the rear extremity of said chassis; a pair of toggle arms hinged to and suspended from the forward extremity of said body at each side thereof; a guide stud carried at each side of said body, the lower arm of each pair of toggle arms being slotted to receive said stud; a shaft connecting the hinge points of said pairs of toggle arms; rollers carried by said shaft; inclined members positioned immediately ahead of said rollers; and cable means for drawing the hinge point of said toggle forwardly so that said rollers will travel upward on said inclined members as the lower arms travel forward on said studs.

ELBERT W. LOWDERMILK.