US2737674A

US2737674A - Street sweeper

Info

Publication number: US2737674A
Application number: US265650A
Authority: US
Inventors: George R Dempster
Original assignee: Individual
Current assignee: Individual
Priority date: 1952-01-09
Filing date: 1952-01-09
Publication date: 1956-03-13
Anticipated expiration: 1973-03-13

Description

March 1956 G. R. DEMPSTER STREET SWEEPER 3 Sheets-Sheet 1 Filed Jan. 9, 1952 mm i w; WP m e D R 2e 5% m 6 @Mw/zmz, flzm fdm ATTOR NEYAS March 1956 G. R. DEMPSTER .STREET SWEEPER 3 Sheets-Sheet 2 Filed Jan. 9, 1952 INVENTOR George R. Dempsi'er BY ATTORNEYS March 13, 1956 G. R. DEMPSTER 2,737,674

STREET SWEEPER Filed Jan. 9, 1952 5 Sheets-Sheet 3 1N VENTOR Geoz 'gje E. Dempsl'er @mmmflfiwm J51 64m ATTORNEYS STREET SWEEPER George R. Dempster, Knoxville, Tenn. Application January 9, 1952, Serial No. 265,650 I 14 Claims. c1. -84) This invention relates to street sweepers and more particularly to a self-propelled sweeper having improved means for collecting and disposing of the sweepings. This application is a continuation-in-part of my prior application Serial No. 221,859, filed April 19, 1951, now abandoned.

Although the use of specially designed and constructed sweepers for cleaning city streets has become a widespread practice, there is still a substantial problem with regard to the handling and disposal of the accumulated sweepings. The material swept from the streets collects in a container in the sweeper, and when the container becomes loaded, either its contents are discharged onto the street pavements in piles for subsequent collection, or the sweeper is driven to the dump or barge and its contents discharged at those points. The latter method of disposal of the sweepings usually requires a rather long haul, often amounting to several miles, and thus involves a substantial loss of sweeping time and a corresponding decrease in the output per sweeper, and necessitates the use of more sweepers with consequently increased equipment and labor costs. Hence in many cases the sweepings are simply dumped on the street pavement for collection at some later time by a dump truck or the like. However, the sweepings quickly dry out after having been sprinkled by the sweeper and the piles of dry sweepings constitute a traflic obstruction and also a hazard to sanitation and health.

The chief object of the present invention is to minimize if not eliminate the foregoing disadvantages of current practice. To this end the invention makes possible an improved sweeping system by the provision of improved equipment whereby successive sweeper loads are collected and stored in a series of detachable containers which can be left at suitable locations and later transported to desired points and there dumped at any convenient time by other equipment of a well known type.

A further object is to provide improved equipment of the type characterized above wherein the sweeper and the containers are provided with cooperating means actuated by the sweeper power plant for lifting a container to and maintaining it in proper position to collect the sweepings, and for lowering the container to and leaving it on the ground at any desired time.

Another object is to provide cooperating means as characterized in the preceding object which are automatic in operation so that the container can be attached to or detached from the sweeper without manual handling.

A still further object is to provide container lifting and supporting means of the type characterized in the preceding objects which means are so designed and constructed that the weight of the container itself maintains it in sweepings-collecting position.

Another object is to provide container lifting means of the aforesaid type which are designed and constructed so that when desired the sweeper itself can discharge the sweepings from the container without detaching it from the sweeper.

Other objects of the invention will appear hereinafter as the description proceeds.

Generally described, a street sweeping system utilizing the invention employs a plurality of containers for each sweeper. Each container and the sweeper are provided with cooperating means such that an empty container can be picked up from the ground by the sweeper and lifted to and maintained in a predetermined position there on to receive the sweepings as the sweeper moves over the area to be swept. Conversely, on reverse operation of said cooperating means, a filled or partially filled container is lowered to the ground for detachment from the sweeper. For these purposes it is advantageous, although not essential, to employ cooperating attaching means on the sweeper and containers of a type such that said means are automatically engaged or disengaged by movement of the sweeper toward or away from the container when resting on the ground.

By the use of such equipment, more efficient and economical utilization of both labor and equipment can be realized without any of the disadvantages mentioned above. For example, a suitable number of empty containers can be spotted in advance at strategically located points in a given area to be swept, being placed in outof-the-way positions in alleys or adjacent to and preferably outside the curbs in side streets, etc. As the sweeper gradually progresses over the area to be swept, these containers are picked up and filled one by one in succession, each container when filled being deposited and left at a similar out-of-the-way point. Thus long hauls are avoided and all of the time of the sweeper and of its operator is used for sweeping, while at the same time the accumulated sweepings are stored in a series of containers so that they are off the streets and present no obstruction to trafiic or hazard to health. The filled containers can then be picked up at any convenient time, dumped and returned to the same or a different location for further use. To facilitate these operations, the containers and the lifting means thereon are preferably such that they can be handled by transporting and dumping vehicles of the type disclosed for example in U. S. Patent No. 2,179,779, as well as by the sweeper itself.

Several embodiments of the invention have been illustrated in the accompanying drawings, but it is to be expressly understood that said drawings are for purposes of illustration only and are not to be construed as a definition of the limits of the invention, reference being had to the appended claims for this purpose.

In the drawings,

Fig. l is a side view of a sweeper and container embodying the invention;

Fig. 2 is a partial front view of the sweeper and container;

Fig. 3 is an enlarged side view of the right-hand end of Fig. 1;

Fig. 4 shows a suitable container for use with the sweeper;

Fig. 5 is an end view of Fig. 4;

Fig. 6 shows another type of container suitable for use with the sweeper;

Fig. 7 is an end view of Fig. 6; 1

Fig. 8 shows still another suitable type of container;

Fig. 9 is an enlarged view similar to Fig. 3 but showinga modified construction;

Fig. 10 is a section on the line 1010 of Fig. 9;

Figs. 11 and 12 are diagrammatic views illustrating the dumping of a container by the sweeper itself; and

Fig. 13 is a detail of a supplemental hook that may be used for the operation shown in Figs. 11 and 12.

Street sweepers of the ype in question are preferably but not necessarily self-propelled vehicles which embody power-driven rotary brushes or like sweeping devices. The sweepingdevices are preferably arranged to throw the sweepings in the direction of movement of the sweeper vehicle, and any suitable means can be employed for collecting the sweepings and delivering them to the container, preferably a conveyor located just ahead of the brushes which carries the sweepings up to an elevated discharge point above the container, the top of the container being open to receive the sweepings discharged from the conveyor. With this arrangement, the container is located at the forward end of the sweeper vehicle, but it will be understood that any other suitable arrangement can be employed.

Fig. 1 shows by way of example a typical sweeper of the type described above which comprises a suitable chassis frame including side channels 1, said frame being supported in any suitable manner on two laterally spaced front wheels 2 and a single rear steering wheel 3 that is mounted in a rotatable frame 4 controlled by a steering wheel 5 in the drivers cockpit. The channels 1 are spaced apart at their front ends and the wheels 2 rotate on stub axles to provide a space between the frame members and Wheels for the container which receives the sweepings. Each side frame member 1 is supported on its associated front wheel axle in any suitable manner. Referring to Fig. 2, the forward end of each frame member is connected by means of gusset plates 6 to the outwardly turned end 7 of a support 8 that extends downwardly to and is mounted on the wheel axle in any suitable manner. The construction is further strengthened at each side by a side plate 9 (Fig. 3) secured to and extending rearwardly from the support 8 with its upper margin inside and secured to the frame member 1. To provide additional strength at the front end of the sweeper, without interfering with the container space mentioned above, the forward ends of the frame members 1 may be connected by a transverse bridge structure comprising channels 10 extending upwardly from the ends 7 of the supports 8 and having their upper ends connected by a transverse channel 11 and suitable gussets 12. The forward end of the sweeper is preferably enclosed in a housing which in the form shown comprises an arcuate hood 13 and side plates 14 extending downwardly from the edges of the hood and secured to the frame members 1, the transverse channel 11 as shown passing through the side walls 14 underneath and close to the hood 13.

The sweeper is driven in any suitable manner, preferably by an internal combustion engine housed in an engine compartment 15 behind the drivers cockpit. The drive from the engine to the wheels and other driven parts may be of any suitable type and is not illustrated in detail. As shown, a transverse drive shaft 16 rotates in suitable bearings mounted on the side frame members 1 and carries at each end a drive sprocket 17 for a drive chain 18 which runs around an idler sprocket 19 and a sprocket 20 (Fig. 2) associated with one of the wheels 2.

The arrangement of the sweeping brushes and the details of mounting and driving the same also may be of any suitable type known to the art and hence need not be described in detail. In general, such sweepers are provided with one or more relatively small side brushes 21 for cleaning gutters, which are arranged to throw sweepings into the path of a main transversely extending brush 22 rotating in a direction to throw the sweepings forwardly with respect to the direction of movement of the sweeper. In accordance with known practice, a forwardly and upwardly inclined flexible belt conveyor 23 provided with suitable flights 24 may be employed to receive the sweepings from the main brush 22 and to carry them upwardly to an elevated discharge point above the container to be described hereinafter. The conveyor 23 may be driven in any suitable manner and runs around an upper roller or the like having end bearings 25 mounted on the side plates 14 of the sweeper housing. A similar roller at the lower end of the conveyor is mounted in suitable bearings 26 supported by side plates 27 which extend downwardly from the side frame members 1. Preferably a pan 28 is connected to the forward edges of these side plates and underlies the lower reach of the conveyor below the frame members 1.

It will be understood that the details of construction thus far described are merely typical of known sweeper constructions, being set forth only by way of example of a sweeper suitable for the application of the present invention.

The container space forwardly of the conveyor 23 and between the frame members 1 and the wheels 2 is thus free and unobstructed to receive a relatively large container for the sweepings discharged at the top of the conveyor. When the container is in its transporting and sweeping-receiving position shown in Fig. 1 and described hereinafter, the front wall of the container preferably forms an arcuate continuation of the sweeper hood 13 and the end walls of the container similarly form continuations of the side walls 14 of the sweeper housing.

Figs. 4-8 illustrate three forms of containers suitable for use with such a sweeper. Referring first to Figs. 4 and 5, the container comprises a generally rectangular body having end walls 29, a bottom 30 which is provided with strengthening rails 31 forming a support for the container when it is resting on the ground, and a front wall 32 which is preferably arcuate to form a continuation of the sweeper hood 13 as mentioned above. Said front wall 32 is hinged to the container at 33 so as to swing open as shown in dotted lines in Fig. 5, and a suitable latch 34 normally maintains it in closed position. The top of the container is provided with an opening 35 to receive the sweepings, which opening may be closed if desired by a suitable lid swing'able from closed position to the dotted line position indicated at 36 in which it lies against an inclined wall 37 along the upper rear side of the container. The lower vertical rear wall 38 of the container is suitably recessed at 39 to house a dumping bail 40 pivoted to the bottom of the container at 41. On each end wall 29 of the container is mounted a casting 42 part of which forms a lifting pin 43.

Figs. 6 and 7 show a container of the drop bottom type comprising a generally rectangular body provided on each of its ends with a casting 44 and lifting pin 45 similar to the lifting pins 43 mentioned above. The external configuration of the container is similar to that described above, the container comprising a lower vertical rear wall 46, an upper inclined rear wall 47, a top opening 48 which if desired may be provided with a lid as described above, and an arcuate front wall 49. However, the front Wall 49 need not be hinged as in Figs. 4 and 5, since the bottom 50 of the container is hinged to the container body at 51 so as to drop open as described below. Preferably the bottom 50 is provided with strengthening rails 52 similar to the rails 31 mentioned above. At the ends of the container bottom are upright walls 53 of triangular shape, the end walls 54 of the container body being similarly cut away so that when the container bottom is closed, one of the bottom end walls 53 cooperates with one of the body end walls 54 to form the complete end wall of the container. As shown in Fig. 7, the plates 44 and lifting pins 45 are mounted on the bottom end walls 53, and the meeting edges of the

walls

53 and 54 are preferably covered by guide plates 55. The

rear walls

46 and 47 are suitably recessed at 56 to house a dumping bail 57.

Fig. 8 shows a container of the tilt type having end walls 81 provided with lifting pins 82, a bottom wall 83 strengthened by rails 84, a vertical rear wall 85 recessed at 86 to receive a dumping bail 87 pivoted at 38 to the bottom 83, and an inclined upper rear wall 89, these parts being similar to the corresponding parts of Figs. 4 and 5. As in the previously described containers, the top of the container shown in Fig. 8 is open at 90 to recei ve sweepings discharged from the conveyor, but in this case no lid is provided. The front of the container com-' prises an upwardly and outwardly inclined wall 91 provided with a dumping lip 92. The space between the top of the container and the dumping lip may be closed by a wall or door 93 hinged to the container body at 94 and forming a continuation of the hood 13 of the sweeper.

The use of the containers described above in the sweeper shown in Figs. 1, 2 and 3 is set forth in detail below. When the filled containers are to be dumped, however, they may be picked up by a transporting and dumping vehicle of the type disclosed in the aforementioned patent, the lifting chains or like lifting means on the vehicle being attached to the lifting pins 43, 45 or 82 for this purpose. The filled containers can thus be lifted onto the dumping vehicle and transported to the desired dumping location, the door 32'of the container shown in Figs. 4 and 5 being meanwhile held closed by the latch 34, the bottom 50 of the container shown in Figs. 6 and 7 being meanwhile held closed by virtue of the fact that the lifting pins 45 are mounted on the drop bottom, and the door 93 of the container of Fig. 8 remaining closed by gravity. At the dumping location, the container is elevated until its dumping

bail

40, 57, or 87 is engaged with a suitable dumping hook, whereupon the lifting means connected to the

pins

43, 45 or 82 are slacked off. The result is that the container shown in Figs. 4 and 5 tilts and its front wall 32 swings open to dump the contents of the container, the latch 34 being first released, or that the drop bottom 50 of the container of Figs. 6 and 7 swings open to discharge its contents, or that the container of Fig. 8 tilts bodily about its bail pivot 88 until the foward wall 91 is downwardly inclined and the door 93 swings open by gravity; all of these dumping operations are of a type well understood in the art.

The container lifting pins 43, 45 or 82 also serve to lift the container to its transporting and sweepings-receiving position on the sweeper. For this purpose the sweeper is provided with cooperating lifting means preferably including attaching elements that are automatically engageable with or disengageable from the lifting pins on movement of the sweeper toward or away from the container when the container is resting on the ground. In the form shown, these attaching elements take the form of openfaced hooks 58 which depend from the sweeper at a height above the ground substantially equal to that of the lifting pins as shown in dotted lines in Fig. 3, but can be elevated to the full line position also shown in Fig. 3. When a container of any of the above types is resting on the ground as shown in dotted lines, the operator of the sweeper drives it forwardly toward the rear wall of the container, the hooks 58 being spaced laterally by a distance somewhat greater than the width of the container so that they move forwardly along the container end walls into engagement with the lifting pins as shown in doted lines in Fig. 3. The sweeper isthen stopped and the lifting means on the sweeper are actuated to elevate the hooks 58 and therewith the container to its transporting position shown in full lines in this figure.

The lifting means on the sweeper is power-actuated, preferably by means of a hydraulic cylinder, and may comprise any suitable mechanical means for elevating the hooks 58 as described above. In the form shown, said hooks are suitably secured as by welding to connecting rods 59 threaded in members 60 so that the height of the hooks above the ground can be adjusted if necessary. Each member 60 is pivoted at 61 on the free end of an arm 62 that is pivoted at 63 in a bracket 64 mounted on the forward end of the side frame member 1. Each arm 62 also has a lug that is pivotally connected at 65 to the end of a piston rod 66 working in a hydraulic actuating cylinder 67, the other end of the cylinder being pivoted at 68 on a bracket 69 mounted on the side frame member 1. The cylinder is operated by hydraulic fluid admitted to way locations as mentioned above.

and exhausted from the cylinder through suitable con' nections 70 and 71. It will be understood that any suitable type of control valve is provided to regulate the supply of hydraulic fluid to the cylinder under the control of the driver.

When the piston rods 66 are drawn into their cylinders, the arms 62 are swung upwardly and inwardly about their pivots 63 from the dotted line position to the full line position shown in Fig. 3, thereby elevating the hooks 58 and the container to transporting position. When the container becomes filled and is to be returned to the ground, on the other hand, the hydraulic fluid control is operated to cause the arms 62 to swing outwardly and downwardly on their pivots to the dotted line position shown in Fig. 3. The container is thus lowered to and rests on the ground and the operator has only to back the sweeper away from the container whereupon the hooks 58 are automatically disengaged from the lifting pins on the container.

Preferably suitable abutment means are provided on the sweeper to limit the upward and inward movement of the container and thus to determine its transporting and sweepings-receiving position. In the form shown, the container tends to swing by its own weight about the pivot 61 in a clockwise direction in the manner of a pendulum, but such motion is prevented by engagement of the vertical rear wall of the container with a transverse vertical plate 72 extending between the side plates 9 mentioned above as shown in dotted lines in Fig. 3. Further the swinging movement of the arms 62 and the resulting upward and inward movement of the container are preferably limited by engagement of the container with suitable abutments secured to the side plates 14 of the sweeper housing. In the form shown, these abutments comprise angle irons 73 extending horizontally along the lower edges of the side walls 14 of the housing in position to be engaged by the upper horizontal edges of the container, and also inclined angles 74 along the adjacent inclined edges of the side walls 14 in position to be engaged by the similarly inclined edges of the container at the ends of their inclined upper

rear walls

37, 47 or 89.

Thus the container is pulled up tightly into its transporting position and is held therein in engagement with the stop angles 73 and 74 and the vertical plate 72. In this position, the

top openings

35, 48 or 90 of the containers are located below the upper end of the conveyor 23 to receive sweepings discharged therefrom. It will be understood that, if desired, the pivot points 61 and 63 and the abutments '72, 73, 74 can be arranged as hereinafter described so that when the container is in its transporting position, the line between the pivot 61 and the lifting pin 45 lies to the left of the pivot 63 instead of to the right and the container is thus locked in transporting position by its own weight.

It will be seen that the

angles

73, 74 not only act as abutments but also reinforce the side walls 14 of the sweeper housing. The forward lower edge of the hood 13 also is preferably stiffened by means of a suitable transverse angle 75 extendlng along this edge inside the sweeper housing. If desired, a portion of the hood 13 may comprise an inspection door '76 hinged at 77 to the hood. In this case the edges of the door 76 are preferably stiffened by suitable angles 78 and the adjacent edges of the hood are preferably stiffened by suitable angles 79. In accordance with usual practice, moreover, suitable Water spray pipes 80 can be provided to sprinkle the pavement in advance of the brushes 21 and 22 described above.

The use of the invention will be understood from the foregoing description without further detailed explanation. Briefly summarized, a plurality of containers such as those described above are located at desired points in a given area to be swept, being preferably placed in out-of-the- The containers can all be placed at one convenient point in this area, but if feasible they will preferably be distributed at various points selected so as to minimize loss of sweeper time. The sweeper is driven up to the first container, the hooks 58 are engaged with the lifting pins, and the container is then lifted to and maintained in transporting position until substantially filled. At this time the sweeper will be close to the next empty container, if the containers are distributed as mentioned above, or is driven to the common point where all the containers are located. The filled container is then deposited on the ground and the next empty container is picked up and carried until substantially filled. This operation is repeated until the sweeper has covered the desired area, the filled containers being left behind for subsequent disposal. Thus all of the time of the sweeper and its operator is used in productive work, while at the same time the containers are deposited in locations where they are out of the way and do not interfere with traffic. Moreover, the storing of the accumulated sweepings in the cointainers avoids the unsightly ap earance and the hazard to health and sanitation that result when the sweepings are simply deposited in open piles. Thus immediate removal of the containers is not necessary. On the other hand, the ultimate disposal of the sweepings can be accomplished quickly and easily whenever desired by a transporting and dumping vehicle of the type shown in the aforementioned patent, most municipal maintenance departments already being provided with such vehicles. As will be readily understood by those skilled in the art, such a vehicle can be used to pick up the containers and transport them one by one to the desired dumping location, where they are quickly and easily dumped and then returned to any desired point for further use.

As mentioned above, it may be desirable to provide container lifting means such that the weight of the lifted container itself maintains it in transporting position without maintaining the hydraulic pressure in the lifting cylinders. Fig. 9 is a view similar to Fig. 3 but showing modified container lifting means whereby this result may be accomplished. For purposes of example, Fig. 9 illustrates a container of the drop-bottom type shown in detail in Figs. 6 and 7. The container bottom 95 is pivoted to the body of the container at 96 and is provided with triangularly-shaped end walls 97 carrying lifting pins 98, the walls 97 cooperating with body end walls 99 to form the complete end walls of the container.

The lifting means are actuated by hydraulic cylinders 101 one on each side of the sweeper, each cylinder being pivoted at 101 to a bracket 102 that is mounted on the side frame member 1 described above. Hydraulic pressure fluid is admitted to the cylinder through supply lines 103 whereby a piston rod 104 can be either retracted into the cylinder or extended to the position shown in full lines in Fig. 9. The container is lifted to its transporting position by suitable means actuated by the piston rod 104. In the form shown, a double-armed lever 105 is pivoted at 106 to the end of the side frame member 1, one arm of said lever being pivotally connected at 107 to the end of the piston rod 164, and the other arm of said lever being pivotally connected at 108 to the end of an arm 109 which hangs freely from this pivot and terminates in a hook 119 adapted to engage the lifting pin 98. It will be understood, of course, that the same or equivalent lifting mechanism is provided on the other side of the sweeper. When the piston rods 1% are retracted, the levers 1G5 swing around their pivots 106 in a clockwise direction to lower the hooks 110 toward the dotted line position shown in Fig. 9, and the arms 109 are moved into engagement with the lifting pins 93 by driving the sweeper toward the container resting on the ground as described above. The cylinders 1% are then operated to extend the piston rods and swing the levers 105 on their pivots in the opposite d' 'cction, thus lifting the arms 109 to bring the bights of the hooks 110 into engagement with the pins 98 and then to lift the container to the transporting position shown in Fig. 9.

By virtue of the arrangement of the parts, including the angular shape of the arms 109, the line between each lifting pin 98 and pivot 108 passes slightly to the left of the pivot 196, and the weight of the container thus acts through the hooks 110 and arms 109 on the levers in a direction tending to swing said levers in a counterclockwise direction about their pivots 106. Thus the container tends to swing further to the left as seen in Fig. 9, but since such further movement is prevented by suitable means such a stop plate 111, the weight of the container automatically holds it in the transporting position. It will be evident that this is true with respect to any of the several forms of container described above.

In some cases it may also be desirable to dump the container without detaching it from the sweeper, and Figs. 9-13 illustrate one suitable means for accomplishing this result. Referring to Figs. 9 and 10, as the piston rods 1% are retracted into their cylinders, the levers 1.65 swing in a clockwise direction and the container carried by the hooks first moves forwardly and slightly downwardly from its transporting position. As a result of such initial movement, the container comes automatically into supporting engagement with suitable supporting means mounted on the forward end of the sweeper and whereby the container is supported independently of the hooks 110. In the case of the drop-bottom type container shown in Fig. 9, said means are arranged to suspend the container in the position shown in dotted lines in Fig. 9 and preferably comprise hooks 112 (Fig. 10) that are pivotally mounted at 113 on the stop angles 73 described above. When it is desired to lift the container from and return it to the ground in the normal manner previously described, the hooks 112 can be moved to and held in the inoperative dotted line position shown in Fig. 10 by any suitable means such as one or more cables 114 operated by the driver. When the hooks 112 are allowed to hang freely from their pivots 113 as shown in full lines, however, they are in position to be engaged by inwardly turned flanges 115 on the upper edges of the container body end walls 99 as shown in dotted lines in Fig. 9 and in Fig. 10, these flanges being preferably strengthened by bars 116 or the like welded or otherwise secured thereto. As shown, the flanges 115 and bars 116 have sufiicient length to permit the container to move farther upwardly and inwardly from the dotted line position of Fig. 9 to the full line position therein. Preferably, guards 117 are secured to the container body end walls in position to prevent fouling of the hooks by accumulated sweepings in the container.

When it is desired to dump the container, retraction of the piston rod 104 first causes the container to move outwardly and downwardly until the flanges 115 and bars 116 come into engagement with the bights of the hooks 112 to suspend the container. With the container thus suspended by the hooks 112, continued or further retraction of the piston rods 104 causes the books 110 to continue their downward movement toward the dotted line position of Fig. 9 and permits the drop-bottom 95 of the container to open. In some cases the sweeper is merely driven to the edge 118 of a dumping pit or the like as shown in Fig. 12 and the amount of drop of the container bottom that is provided by the movement of the hooks 110 to their lowermost positions is sufficient for dumping. In case greater opening of the container bottom is desired, however, the procedure illustrated by Figs. 11 and 12 can be followed. Fig. 11 is a somewhat diagrammatic view in which the container bottom has been dropped to the point also shown in dotted lines in Fig. 9 where it has come into engagement with the ground, after which the hooks 110 have been moved downwardly away from the lifting pins 98, this operation being performed when the sweeper has been driven close to the dumping pit. Suitable extensions such as the supplemental hooks 119 (Fig. 13) are now applied to the freely hanging hooks 110 so as to increase the effective length of the arms 109. As

shown, said supplemental hooks 119 are provided with hooked ends 120 adapted to engage in the hooks 110 and with opposite hooked ends 121 turned at right angles and adapted to engage the lifting pins 98. The cylinders 100 are now operated to lift the arms 109 and bring the hooked ends 121 into lifting engagement with the pins 98. Thus the bottom 95 of the container can be lifted sufiiciently to clear the ground and the sweeper can be driven forwardly to the dumping pit as shown in Fig. 12, the cylinders 100 being then operated to drop the bottom 95 to the full extent permitted by the length of the supplemental hooks 1B. The empty container can then be returned to its transporting position by reversing the above sequence of operations.

Because of uneven distribution of the load in the container and/ or the weight of the container itself, the container may tend to tilt around the lifting pins as it is lifted to transporting position and returned to the ground, or about the hooks 112 when suspended in dumping position. In such cases it is desirable to provide one ormore lugs on the end walls of the container which are located in position to engage the

arms

59 or 109 of the lifting means to prevent such tilting. For example, Figs. 8, 9, 11 and 12 show one such lug 122 located to prevent undue tilting of the container in a counterclockwise direction. It will be understood that a similar lug or lugs can be provided on the containers shown in Figs. 47 if desired.

It will be understood that the invention is not restricted to the details specifically set forth above by way of example but is susceptible of other embodiments, and also that various changes can be made in the form, details of construction and arrangement of the parts without departing from the spirit of the invention. Reference should therefore be had to the appended claims for a definition of the limits of the invention.

What is claimed is:

1. In a street sweeper of the type comprising a vehicle having street sweeping means and means for elevating the sweepings to and discharging them at an elevated point, a container having an opening to receive said discharged sweepings, lifting pins on said container, pivoted hook members depending swingably from said vehicle in position to engage and disengage said pins on movement of said vehicle toward and away from said container when resting on the ground, power means on said vehicle for lifting said hook members and moving them longitudinally relative to the vehicle and therewith said container to a transporting and sweepings-receiving position below said elevated point, and means on said vehicle for limiting the lifting and longitudinal movement of said container to determine said position.

2. A street sweeper as defined in claim 1, said power means comprising pivoted arms from which said hook members depend and hydraulic means for swinging said arms on their pivots to raise and lower said hook members.

3. In a street sweeper of the type comprising a vehicle having street sweeping means and a conveyor for elevating the sweepings to and discharging them at an elevated point, a detachable container normally maintained in a transporting position at one end of said vehicle and having a sweepings-receiving opening located below said elevated discharge point, lifting pins on said container, lifting means on said vehicle including attaching members depending swingably from said vehicle for engagement with and disengagement from said pins on movement of said vehicle toward and away from said container when resting on the ground, and power means on said vehicle for actuating said lifting means thereon and moving said container both upwardly and inwardly toward said vehicle, said vehicle having abutments for limiting the upward and inward movement of said container and thus determining said transporting position when said container is moved into engagement therewith.

4. A street sweeper as defined in claim 3, said lifting 10 means including arms pivoted on said vehicle to which said attaching members are connected for relative swinging movement, said arms swinging outwardly and downwardly on their pivots to lower said attaching members for engagement with said pins and upwardly and inwardly to lift said container to said transporting position.

5. A street sweeper as defined in claim 4, said lifting means being constructed and arranged so that when said container is in its transporting position, lines between said lifting pins and the connections of said attaching members to said arms pass inwardly of the pivots of said arms on said vehicle.

6. In a street sweeper of the type comprising a wheeled vehicle having a chassis frame open at its front end and formed in part of spaced side members supported on the forward wheels, and also having sweeping means adapted to discharge sweepings at an elevated discharge point into a container located therebelow in a transporting position between said side members and forward wheels, a detachable container adapted to occupy said transporting and sweepings-receiving position, lifting means on the ends of said container, lifting means mounted on said side members and including depending swingable elements for engagement with and disengagement from the lifting means on said container on movement of said vehicle toward and away from said container resting on the ground, power means on said vehicle for actuating said lifting means thereon to elevate said container between said side members and to move it inwardly between them to said transporting position, and abutment means on said vehicle to limit movement of said container in said position.

7. A street sweeper as defined in claim 6, said lifting means on said vehicle comprising arms pivoted on said side members, said depending elements comprising hook members pivotally connected to said arms and depending therefrom on the outer sides of said side members, said lifting means on said container projecting outwardly from the ends thereof below said side members for engagement with said hook members.

8. A street sweeper as defined in claim 6, including side plates on said vehicle extending downwardly from said side members, and said abutment means including a transverse member connecting said side plates, a portion of said container in said transporting position extending between said side plates and engaging said transverse member.

9. A street sweeper as defined in claim 8, said lifting means on said vehicle comprising arms pivoted on said side members and said depending elements being connected to said arms for relative swinging movement, said power means swinging said arms upwardly and rearwardly to elevate said container, said depending elements extending forwardly and downwardly when said container is in said transporting position and said arms and depending elements being arranged so that lines between said container lifting means and the connections of said depending elements to said arms pass inwardly of the pivots of said arms on said side members, whereby the weight of said container tends to maintain it in engagement with said transverse member.

10. A street sweeper as defined in claim 9 in which said sweeping means includes a forwardly and upwardly inclined conveyor for conveying sweepings to said elevated discharge point, and wherein said container has a top opening which is located below said discharge point when said container occupies said transporting position, an inclined upper wall which is substantially parallel to and underlies said conveyor, and a substantially vertical lower wall which engages said transverse member.

11. In a street sweeper of the type having power-driven sweeping means and power-driven conveying means for elevating the sweepings to and discharging them at an elevated point, a container having an opening to receive said discharged sweepings, lifting means on said container, cooperating lifting means on said sweeper adapted for engagement with and disengagement from the lifting means on said container upon movement of said sweeper toward and away from said container when resting on the ground, power means on said sweeper for elevating said cooperating lifting means and moving them longitudinally relative to the sweeper and therewith said container to a transporting position in which said opening is located below said elevated discharge point, and suspension means on said sweeper positioned to engage and suspend said container independently of said lifting means for dumping, said container and suspension means having cooperating members engageable to suspend the container at a point in its path of movement away from and spaced from said transporting position.

12. A street sweeper as defined in claim 11, said suspension means comprising pivoted hooks movable to inoperative position when said container is to be placed on the ground.

13. A street sweeper as defined in claim 11, said suspension means comprising hook members on opposite sides of said sweeper positioned to be engaged by the upper portions of the end walls of said container as it is moved by said power means from its transporting position toward its position of rest on the ground.

14. A street sweeper as defined in claim 11, said container being of the drop-bottom type having a top opening to receive said discharged sweepings, said lifting means being secured to the bottom of said container, whereby movement of said cooperating lifting means away from said transporting position moves said container from its transporting position to a position in which it is suspended by said suspension means and further movement of said cooperating lifting means causes the bottom of said container to open for dumping.

References Cited in the file of this patent UNITED STATES PATENTS 242,971 Pennypacker June 14, 1881 493,950 Van Wagenen Mar. 21, 1893 671,280 .lene Apr. 2, 1901 1,921,233 Kuchar Aug. 8, 1933 2,179,779 Dempster Nov. 14, 1939 2,313,514 Brooks Mar. 9, 1943 FOREIGN PATENTS 589,947 Great Britain of 1947