EP1482824A1 - Litter vaccum - Google Patents

Abstract

A mobile litter pickup vehicle has a pair of forward corner brushes (32, 34) independently mounted on articulated arms (46) so that the brushes (32, 34) may be moved in the event an obstacle is encountered to avoid damage to the brushes (32, 34) or to the object. An air recirculating system is employed for prolonging the life of the final outlet filter, and an impermeable trash bag (133)may be used for disposing of the contents of a primary scrim collection bag (131) .

Description

LITTER VACUUM

Related Application

This application claims benefit under 35 U.S.C. 120 of co-pending provisional

application S.N. 60/273,977 filed March 7, 2001 for LITTER VACUUM.

Field of the Invention

The present invention relates to motor-driven or riding vacuum machines of

the type used to clean litter, debris and dirt or sand from public parkways, streets,

sidewalks, and large open areas such as parking lots, parks, and the like. Vehicles

of this type are designed to recover a large range of litter, including dust, dirt, sand

and debris, bottles, cans, clippings, hedge trimmings, and the like.

Summary of the Invention

The present invention relates to improvements in litter vacuums. A first

improvement is directed to the suspension of the vacuum housing or "shoe" and the

mounting of the forward or "corner" sweeper brushes. An actuator such as an

hydraulic cylinder operated by the operator rotates a crank which lifts the vacuum

shoe. A four-bar or parallelogram linkage suspends the vacuum shoe to the chassis

or frame of the vehicle so that it may be moved between a lowered use position and

a raised transport position. Moreover, the forward portion of the vacuum housing

is mounted by means of linkages having slots or "lost motion" links so that when the

vacuum housing is in the lowered or use position and the housing rests on rollers or

wheels to provide the proper operating height, the vacuum housing may ride over

obstacles or bumps independently of the corner sweeper brushes. At the same time,

if the operator sees an unusually large object in the way, such as a quart or liter

plastic bottle, he may actuate a cable to raise the vacuum jjhoe to permit it to accommodate the large object, and suction the object up. Again, this raising of the

vacuum shoe is independent of the sweeper brushes.

The sweeper brushes are mounted to the same hydraulic lift mechanism which

raises and lowers the vacuum shoe. However, the brushes may be latched in the

raised or storage position to permit the vacuum shoe to be used on gross or outdoor

carpeting. The sweeper brushes are mounted on linkages which permit an articulated

motion of the brushes. Each brush is mounted similarly to the other so that only one

need be described. The brushes operate independently of each other. If a corner

brush encounters an object head-on in the sweeping position, it is permitted, against

a spring bias, to rotate outwardly and rearwardly, about a vertical pivot located

inwardly and rearwardly of the vertical center of the brush. This permits the brush

to move rearwardly of the forward-moving machine without damage. It also increases

the moment arm by which a second articulated arm on which the brush is mounted

may move inwardly toward the center of the machine, folding the brush beneath the

chassis or frame in cooperation with the first articulating link and protecting the

brush against further damage.

Thus, the shoe and brushes may be raised for transport or storage or lowered

for use while the brushes may be latched in the storage position as the vacuum shoe

is used for suctioning debris, and the shoe may be independently raised for larger

objects.

The vacuum shoe is equipped with a door mounted to close or adjust the inlet

opening by a cable controlled by the operator. The door is provided with a flexible

lower strip to adjust to the surface being cleaned. By closing the inlet opening, the operator may control the velocity of the air entering the front of the vacuum shoe and

directing the incoming air to pass close to the surface being cleaned. This section

entrains dust, debris and smaller particles such as sand into the suction air stream

from which the debris is filtered and collected.

Another improvement incorporates a scrim bag to collect and filter the debris

in a hopper which may be pivoted to dump the contents. This improvement renders

unnecessary a supplemental refuse container. The scrim bag is disposable and

coupled to an inlet from the blower to receive the debris. Air passing through the

scrim bag and not passing through the main filter is recirculated to the vacuum shoe.

A disposing plastic bag is mounted in a flat configuration adjacent a rear hopper

door. When it is desired to dispose of the material collected in the scrim bag, the

hopper door is unlatched, the hopper is rotated to the dump position, and the scrim

bag and its contents falls into the plastic trash bag which is then secured so the

contents may be disposed of.

As an alternative, when the debris is primarily larger material such as lawn

clippings or trimmings or cups and plates, a scrim bag may be used to collect debris

and the scrim bag may be emptied directly into a refuse container.

The present invention also includes provisions for a recirculation aperture in

the hopper at a location between the solid walls of the hopper and the scrim bag or

other filter bag in the hopper. Refuse entrained in the suction air is introduced

through the hopper into a pre-filter bag. Air (and some smaller particles) passes

through the filter bag and exits the hopper, through a final filter which extracts

"fines" or dust from the air before exhausting the air into the atmosphere. The debris, once it enters the filter bag, tends to settle down because the velocity of the

suction air decreases in the larger volume of the hopper. By placing the inlet of a

recirculation conduit between the wall of the hopper yet outside the filter bag, the

recirculating aperture acts as a differential pressure regulator responsive to the

pressure across the final filter. If the final filter becomes clogged, the pressure across

it increases, and a greater amount of air is then recirculated to the vacuum housing.

This extends the useful time of the final filter before replacement or cleaning the final

filter.

Other features and advantages of the present invention will be apparent to

persons skilled in the art from the following description of the illustrated embodiment

accompanied by the attached drawing whether identical reference numerals will refer

to like parts in the various views.

Brief Description of the Drawing

FIG. 1 is an upper right frontal perspective view of a litter vacuum machine

incorporating the present invention;

FIG. 2 is a right side view of the machine;

FIG. 3 is a left side view of the machine of FIG. 1;

FIG. 4 is a front view of the machine of FIG. 1;

FIG. 5 is a fragmentary right side view of the suspension system for the

vacuum shoe and the sweeper brushes lowered to the use position;

FIG. 6 is a view similar to FIG. 5 with the vacuum shoe and sweeper brushes

raised for storage; FIG. 7 is a view similar to FIG. 5 with the vacuum shoe raised to

accommodate larger objects in perspective, of the suspension system for the vacuum

housing;

FIG. 7A is a view similar to the FIG. 5 with the brushes latched in the raised

position;

FIG. 8 is a right upper frontal perspective view of the vacuum shoe partially

cut away to show the adjustable door;

FIG. 9 is a vertical cross section view of the vacuum shoe taken from the right

side;

FIGS. 10, 11, 12 and 13 are diagrammatic top views showing the operation

of the articulated linkage for the sweeper brushes;

FIG. 14 is a left upper frontal perspective view of the vacuum shoe illustrating

the left portion of the mounting of the brush and the left portion of the lift

mechanism;

FIG. 15 is a partial view, in perspective, of the articulate arm for the right

corner brush;

FIG. 16 is an upper right frontal perspective view of the vacuum shoe, hopper,

blower and portion of the machine exterior housing illustrating the air intake path;

FIG. 17 is a view similar to FIG. 16 omitting the blower and hopper and some

of the intake recirculation conduit to better illustrate the flow of recirculating air

from the hopper back to the vacuum shoe;

FIG. 18 is an upper left perspective view showing a portion of the machine

and illustrating the hopper in the raised position; FIG. 19 is a perspective view taken from the rear, left side with a portion of

the hopper broken away to illustrate the placement of the refuse bag within the

hopper, with the hopper door raised;

FIG. 20 is diagrammatic view illustrating a vertical cross sectional view

looking toward the left of the machine, and taken through the center of the hopper,

illustrating the location of a scrim bag and a plastic trash bag in the hopper, with the

hopper in the use position;

FIG. 21 is a view similar to FIG. 20, with the hopper raised to the dump

position and the hopper door open, showing the dumping of the scrim bag into the

poly bag for disposal.

Detailed Description of the Illustrated Embodiment

Referring first to FIGS. 1-4, there is shown a litter vacuum machine

incorporating the present invention. The machine is generally designated by

reference numeral 10 in the drawing, and it includes a frame or chassis, a pair of

front wheels 12, 13 carried by the frame, a rear steerable wheel 15 which is driven,

conventionally, by an hydraulic motor powered by a diesel engine carried by the

frame and housed within the molded housing or outer casing 17. Mounted above the

forward portion of the outer casing 17 is a driver's seat 19 in front of which is a

steering wheel 20 mounted in a steering pedestal 24 located at the forward end of

the frame of the vehicle.

It will be observed from FIGS. 2 and 3 that the operator's seat 19 is located

between and above the forward wheels 12, 13. The drive, steering linkage and frame

are conventional and need not be described in further detail. Rather, the invention is related to the mounting of a vacuum (i.e., suction) hopper or "shoe" 27 beneath

the forward portion of the frame, the suspension of left and right sweeper brushes

generally designated 32 and 34, the emptying of the debris hopper 35 and the

recirculation of suction air from the hopper to the vacuum shoe. The hopper 35 is

mounted above the rear portion of the casing 17 behind the driver so as to avoid

obstructing his/her view during normal operation which is in a forward direction, and

leaving unobstructed lateral views, as can be seen from FIGS. 2 and 3.

In operation, the motor of the machine, in addition to driving the rear wheel

15, drives a conventional suction fan or blower housed within the molded casing 17

and beneath the driver's seat 19. The input of the blower is coupled, as will be

further described, by means of a large conduit to the vacuum housing 27. In the

operating position, the vacuum housing may ride along the surface to be cleaned or

slightly elevated, at the option of the operator. The suction or vacuum air, as will be

further described, picks up the debris and dust, which passes through the blower and

is further crushed or broken, and then delivered by means of a conduit 36 to the

hopper 35 (FIG. 1).

Turning now to FIGS. 5-8, the vacuum shoe 27 includes a tubular coupling 28

to which is mounted a flexible suction hose 29 connected to the inlet of the blower.

The coupling 28 is mounted to the top plate 38 (FIG. 8). A smaller coupling 30 is

also mounted to the top plate 38 and is coupled to a flexible hose 31 for delivering

recirculated air to the shoe 27. FIGS. 5-8 illustrate the improved suspension for the

vacuum housing 27 and the forward left and right sweeper brushes 32, 34 (see FIGS.

1, 2). The mounting of the brushes 32, 34 is the same, except that the mount for the left brush is the mirror image of the mount for the right brush, as will be

understood. Thus, the mounting for only one of the brushes need be described in

further detail for an understanding of the improvements. The operation of each

articulated suspension arm for the brushes is independent of the other.

As can be seen from FIG. 8, the forward portion (i.e. , inlet opening) of the

vacuum shoe 27 is provided with an adjustable door or flap designated at 39, to

permit the shoe 27 to receive debris. The forward portion of the housing, at the left

and right sides, is provided with rollers or wheels 40 for engaging the ground when

the vacuum housing is lowered to the use position, as seen in FIG. 5 (and FIG. 7A)

for suctioning up the debris within the vacuum shoe 27.

A pair of arms 42 (FIG. 6) are fixed, as by bolting, to the vacuum shoe 27.

The rear portions of the arms 42 are connected by means of a transverse rod 43

which, in turn, is rotatably carried by the frame of the machine so that the arms 42

may be rotated between the lowered or use position of FIG. 5 and the raised or

transport position of FIG. 6 by an actuator such as hydraulic cylinder (FIG. 7). In

addition, the operator may raise the vacuum show 27 to suction larger objects while

the actuator is in the use position with the brushes sweeping the ground, as seen in

FIG. 7. This is accomplished by a pivot handle 110 and cable 111 connected

between the handle 110 and the front of the vacuum shoe at 112. The handle 110

is accessible from the operator's station and pivotally mounted to the frame at 114

(FIG. 5). The front of the vacuum housing 27 is mounted by means of left and right

slotted links 44 (the left one being shown in FIG. 14 and the right slotted link 44

being shown in FIG. 5) pivotally mounted to respective ones of the forwardly extending arms support arms 42 of the pivoted show support. Referring to FIGS. 5-

7A, the upper ends of the slotted links are pivotally connected to left and right side

lift plates 47. The lift plates 47, in turn, are mounted to and supported by an

actuator mechanism which includes left and right four-bar linkages 48, as will be

described presently. The lift plates also support left and right articulated arms 46

which, in turn, carry the brushes 32, 34. These structures, including the slotted

links, lift plates, articulated arms and four-bar actuating linkages are similar on left

and right sides.

The four-bar linkage 48, as seen in FIGS. 5 and 7, includes a lower link 49

(which acts as a crank arm) and an upper link 50. A portion of the frame of the

machine, in the form of two downwardly and forwardly extending support struts, is

designated E in FIGS. 5 and 7. The forward portion of the upper link 50 is pivotally

connected at its forward end, to the frame F at 51 (see also FIGS. 16-17), and its

rear end is pivotally connected at 52 to the right lift plate 47. The forward end of

the lower parallel link or crank 49 is fixed to a rock shaft 55 (FIG. 14) which is

journaled in forward extensions of the frame E. Downwardly extending tabs 56 are

welded to the rock shaft 55. The rear ends of the parallel links 49, 50 are pivotally

connected to associated lift plates 47.

Turning now to FIG. 14, an hydraulic cylinder 58 has its rod end pinned to

the tabs 56 welded to the rock shaft 55, and its cylinder end pinned to the frame F.

Thus, the lower links 49 of the parallel linkages 48 are arms of a crank actuated by

the cylinder 58. When the cylinder 58 is retracted the rock shaft 55 rotates

clockwise as viewed from the right (FIG. 5) relative to the frame E of the machine, thus raising the lift plates 47 which carry the front end of the vacuum shoe via

slotted links 44 and the articulated arms 46, thereby raising both the vacuum shoe

27 and the brushes 32, 34 to the storage or transport position seen in FIG. 6. The

parallel linkage 48 maintains the articulated arms 46 in a generally horizontal

disposition for all elevations of the articulated links 46, as will be seen by comparing

FIGS. 5 (the lowered or use position) and 6 (stored position) except when the

articulated arms are latched in the raised position, as will be described.

As indicated in FIGS. 5 and 6, the slotted links 44 which suspend the forward

portion of the vacuum housing 27 from the rear of the lift plates 47, receive bolts or

pins, such as the one designated 59 in FIG. 7, secured to the side of the vacuum

housing 27. The pins 59 are free to ride in the slots so that the forward portion of

the vacuum housing 27 may raise as the wheels 40 encounter a bump or other

obstruction without affecting the setting of the rotating sweeper brushes 32, 34.

Turning now to the articulated arms 46, reference is made to FIGS. 5, 6, 7

and 7A. As mentioned, FIGS. 5 and 6 illustrate the right side articulating arm 46,

and the left articulating arm (shown in FIGS. 10-13, and 14) is substantially the

same as the right arm except in mirror image.

Turning first to FIG. 14, the articulating arm 46 is pivotally mounted to lift

plate 47 by means of a plate 53 having two curved slots 54 and 54A and a pivot

point 546 (FIG. 6). Slots 54 and 54A and pivot 54B receive pin 61 fixed to the lift

plate 47. A first link 63 is pivotally mounted to the plate 53 for rotation about a

vertical pivot axis as at 64. A forward link or arm 65 (FIG. 15) is mounted for rotation about a vertical pivot 66 (FIG. 15) to the forward portion of the first link

63. The right side brush assembly 34 is mounted to the forward link 65.

Turning now to FIG. 15, the right side link or arm 63 may rotate in a

counterclockwise direction, which viewed from above, from its normal, fore-to-aft

direction (the use position) seen in solid line in FIG. 15. A stop member 68 (FIG.

14) prevents the inner link 63 from rotating outwardly beyond the fore-to-aft

position parallel to the direction of travel of the machine. In other words, the first

or inner links of the articulating linkages are permitted to rotate laterally inwardly

toward the center of the machine, thereby moving the associated brush assemblies

as diagrammatically illustrated in FIG. 11 for the left brush, inwardly. A first

extension spring 70 (FIG. 5) is connected at it forward end to the outboard side of

the link 63 by means of a peg 71, and its rear end is connected by means of a peg

72 to the lift plate 47. The spring 70 is pre-loaded under tension, so that the rear

arm 63 is biased outwardly toward the use position shown in FIG. 10, limited by the

stop 68 (FIG. 5). However, as will be explained, a laterally inward force caused by

an impact may cause the arm 63 to rotate inwardly.

Similarly, a second extension spring seen in FIGS. 5 and 15 and designated 74

is connected in tension between a pin 75 at the rear of the link 63 and forward link

65, biasing the forward link 65 to the position shown in solid line in FIG. 15 which

is the forward limit or normal use position. An impact in the direction of the arrow

in FIG. 15 would cause the arm 65 to rotate clockwise as viewed from the top (for

the right linkage seen in FIG. 15), and thereby causing the brush assembly 34 to

move rearwardly to the position shown in dashed line. Again, the link 65 (which is formed generally forwardly and thence outwardly of the normal position of the first

link 63 as seen in FIG. 15) is limited at the forwardmost position by a stop 77

engaging the link 63 so that it may not rotate further inwardly toward the center of

the machine.

Turning now to FIGS . 10-13, the range of motions for the articulating linkages

supporting the brushes is illustrated for the left brush 32. As seen in FIG. 10, the

articulating linkage is in the normal position, the outline of the machine chassis or

frame being schematically illustrated by the solid chain line. In the normal use

position of FIG. 10, the first or rear articulating link 63 extends parallel to the

direction of travel, and the forward, angled link 65 suspends the left brush (and its

associated housing and drive motor) in the normal, desired use position, leaving the

brush 32 capable of cleaning corners to the left of the machine or beneath overhangs,

or over normal, flat terrain. In the event of a side impact, caused either by

movement of an object from left to right, engaging the brush 32 or its housing, or by

steering the machine too close to a wall or other obstruction on the left side of the

machine, the articulating linkage as a whole is permitted to rotate clockwise about

the rear pivot 64, moving the brush 32 inwardly toward the center of the chassis and

reducing damage to the brush assembly.

In the case of a forward impact (i.e., directly from the front), it will be

observed that the link 63 is located in a fore-to-aft direction and has little or no

freedom of movement in the case of a direct, head-on collision. However, the angled

forward link 65 extends laterally of a link 63 and is thus permitted to move against

the bias of spring 74 (not seen in the diagrammatic showings of FIGS. 10-13) and to rotate counterclockwise about the forward pivot 66 to a position rearward of the

forward section of the machine frame, as illustrated in the diagrammatic showing of

FIG. 12.

In the case where the machine is turning toward the right, or encounters a

head-on collision at a higher speed and it is therefore more difficult to alleviate by the

operator, it will be observed from FIG. 12 that the moment arm exerted by the

angled link 65 about the rear pivot 64 has increased relative to the moment arm at

the normal position seen in FIG. 10. Thus, there is more leverage (counterbalancing

the force of spring 70) to rotate the rear link 63 clockwise to the protected position

of FIG. 13. In this case which is illustrated by a right turn which is improperly

executed, the rear link 63 pivots inwardly about the rear pivot 64, and the forward,

angled link 65 rotates counterclockwise about the forward pivot 66. The

combinations of the two motions bring the brush 32 to nest within the more

protective confines of the machine frame, thereby reducing damage to the brush

assembly 32 and the articulated linkages.

There are times when it is desirable for the operator to manually raise the

forward portion of the vacuum housing, for example, in the event that a large

container is encountered, such as a quart-size beverage container. To accommodate

this, the previously described pivoted lever 110 adjacent the operator's position, and

the wire cable 111 (FIG. 7) are used to manually raise the vacuum shoe 27 as seen

in FIG. 7. The lever 110 enables the operator, without substantially reducing speed,

to expand the inlet opening of the vacuum housing to receive such larger objects without interfering substantially with the operation of the machine and the efficient

pick-up of trash and debris.

Turning now to FIG. 7, on each side of the frame F there is a latch member

designated 77 which is pivotally mounted to the frame. A pin 78 is mounted to the

inner link 63 in a position such that the operator may manually raise the side broom

34 and its associated articulated linkage to the position shown in FIG. 7A, and the

latch 77 rotated to engage and secure to the pin 78, thereby elevating the brush 34

to the raised position seen in FIG. 7A while permitting the vacuum shoe 27 to remain

in the use position. Such a position is useful for suctioning debris from lawns or for

suctioning trimmings adjacent hedges or the like. The vacuum shoe 27 includes an

upper metal housing 27A mounted to the lift arms 42, and a lower flexible skirt 27B

depending from the housing 27A; the skirt 27B may be made of polyurethane.

Turning now to FIGS. 8 and 9, the vacuum shoe 27 is seen in more detail. A

flap or door 39 having its lower edge provided with a flexible strip 77 of a material

such as vinyl or rubber is pivotally mounted at 78 to the forward wall of the housing

of the vacuum shoe 27. A curved link 79 is fixed to the flap 39 and extends

upwardly through the top wall 38 of the housing of the vacuum shoe 27, as best seen

in FIG. 8. A cable 84 is pivotally connected at 85 to the curved link 79. The cable

84 is part of a cable assembly, the sheaf of which is mounted to the top wall 38 of

the vacuum shoe 27 by means of a bracket and clamp generally designated 86. The

remote end of the cable assembly is carried by the frame of the machine adjacent the

operator's station, and the cable may be extended or retracted by means of a knob

88, seen in FIGS. 1 and 8, adjacent the operator's position. When the cable 84 is extended by the operator, the link 75 is forced to the forward position shown in solid

line in FIG. 9, thereby raising the flap 39 to the position shown in solid line and

opening the inlet of the vacuum shoe to its maximum position. By moving the cable

84 rearwardly, the operator is able to lower the flap 39 to any desired position, the

lower limit being shown in FIG. 9 with the flexible strip 77 engaging the surface

being treated. As the inlet opening is adjusted to a smaller size, that is, closed by

lowering the flap 39 to the position shown in dash line in FIG. 9, the velocity of the

air suction entering the vacuum shoe is increased. Moreover, the air is routed

through a location adjacent the surface being treated or cleaned. The higher velocity

and the location of the inlet air stream agitates dust and small debris which is then

entrained in the suction air and routed through the blower and into the collection bag

within the hopper 35, as will be described below.

The top of the vacuum shoe is provided with a first coupling member 28 which

is connected to a flexible hose, the other end of which is connected to the inlet of the

blower. The vacuum shoe is also provided with a smaller coupling member 30 which

receives a flexible conduit for recirculating air, as will be described further below.

A forward baffle 95 routes the suction air drawn through the inlet opening of the

vacuum shoe directly to the coupling member 28 which communicates with the inlet

of the blower. Baffle 96 routes the recirculated air from the coupling member 30

forwardly to the rear portion of the baffle 95 and thence upwardly to be recirculated

through the coupling member 28.

Referring now to FIGS. 16 and 17, the air recirculation system for the litter

pickup machine will be described. As described in connection with FIG. 8, suction air is routed from the vacuum shoe 27 through a connecting coupling 28 and a

flexible conduit 29 to a blower 97.

The outlet end of the flexible conduit 29 is connected to a tubular inlet conduit

98 by means of a hose clamp 100 having an over-center latch 101. Thus, by a

simple unlatching action, the outlet end of the conduit 29 may be released from the

inlet section 98 to the blower 97 for inspection or removing debris. The inlet section

98 is also provided with a side inlet section 102 which is adapted to receive a

flexible conduit (see 104 in FIGS. 18, 19) which may be used for a manual suction

tool adapted to clean places which cannot be reached by the vehicle, such as under

benches or other seating. A conventional shutter plate may be used to shut off

suction from the manual tool when it is not in use, and the conduit may be wrapped

around the rear of the vehicle, beneath the level of the hopper, for storage when not

in use, all of which features are known in the art, and need not be described for

detail.

The discharge end of the blower 97 is coupled to a conduit 36 in the form of

an elbow, the downstream end of which is bolted to the front wall of the hopper 35

so that the debris is delivered into the interior of the hopper directly.

The rear of the hopper 35 is provided with a door 105 which is hinged at 106

to swing upwardly (see FIG. 19). Moreover, as seen in FIG. 18, the rear of the

hopper 35 is hingedly mounted by means of hinge members 107 to the rear of the

machine for movement between the use position of FIG. 1 and the dumping position

of FIG. 18. The outlet of the blower 97 is provided with a gasket 109 of flexible, sealing material, such as neoprene, so that when the hopper is lowered, the conduit

36 forms a seal with the outlet of the blower.

The hopper 35 includes a partial side wall on either side, the left side partial

bottom wall being designated at 116 in FIG. 18. An outlet aperture 117 is provided

in the bottom wall 116 which serves as a discharge aperture for air passing through

the filter bag (as will be described) and being recirculated back to the vacuum shoe,

as will now be debunbed. The aperture 117 is aligned with a similar aperture 118

(FIGS. 17 and 18) which is provided with a sealing gasket 119. The aperture 118

is formed in a molded lateral housing section or "fender" generally designated 120.

The left fender 120 is a sealed shell except for the inlet opening 118 and a discharge

opening designated 121 in FIG. 17.

The fender 120 includes a recess 123 for a battery, and it also includes a

recess 124 for accommodating a fuel tank, and a clean out plug 126. Otherwise, as

mentioned, the fender 120 acts as a conduit for the recirculating air as indicated by

the arrows 125. As can be seen, the recirculating air from the hopper enters the

opening 118, travels downwardly adjacent the recess 124 and thence beneath the

battery recess 123 and thence upwardly and forwardly through a discharge conduit

127 and the discharge aperture 121 into the previously described conduit 31, the

outlet end of which is connected to the recirculating air connector 30 on the top wall

38 of the vacuum shoe 27.

Turning now to FIGS. 19-21, as best seen in FIGS. 20-21, the conduit 36

extending from the outlet of the blower to the front wall of the hopper 35 extends

into the interior of the hopper, and the top portion is provided with a deflector 130. A first collection bag 131 has its opening mounted to the interior extension of the

conduit 36, and it is secured by means of a stretched cord 132 or other elastic band

to the extension of conduit 36.

The bag 131 may be a "scrim" bag, made of pressed polyethylene fibers so

that it permits air to flow through it but traps larger particles and most debris. Air

passing through the scrim bag 131 passes through a filter mounted in the top of the

hopper 35 which filters out fine particles. Air which does not pass through the filter

is routed through the outlet opening 117 (FIG. 18) and into the fender 120 for

recirculation to the vacuum shoe as described above.

After a period of use, the outlet filter begins to clog as the fine materials collect

on it. This increases the flow of recirculation air back to the vacuum shoe, and this

acts as a pressure regulator, maintaining the collection efficiency of the system until

the filter is changed. Obviously, the filter must ultimately be changed.

When it is desired to empty the scrim bag 131, the hopper door 105 is

opened, and, if a trash bag is not used, the scrim bag may simply be pulled off the

extension 132 and the elastic band remains on the bag, acting as a closure member.

Alternately, the hopper 35 may be tilted to the raised position seen in FIGS. 18, 21.

The scrim bag 131 then falls off of its own weight onto the ground or, if a trash bag

is used, into that bag which may then be removed from its holder and the scrim bag

and its contents may be disposed of in the trash bag 133.

When the scrim bag 131 is used for collecting refuse, provision may be made

for including an impermeable, conventional trash, lawn or leaf bag 133. The opening

of the trash bag 133 is secured about the opening covered by the hopper door 105 by means of a wire hoop 136 which is inserted into the opening of bag 133 and is

then releaseably fit into an angled holder members 137 and 137A as shown in FIG.

20.

As an alternative, the scrim bag may be replaced by a nylon mesh bag having

a water-impermeable bottom.

Having thus disclosed in detail the illustrated embodiment, persons skilled in

the art will be able to modify certain of the structure which has been described and

to substitute equivalent elements for those disclosed; it is, therefore, intended that

all such modifications and substitutions be covered as they are embraced within the

spirit and scope of the appended claims.

Claims

WE CLAIM:

1. In a mobile vehicle adapted for cleaning a surface having a plurality of

support wheels, the combination;

a frame;

first and second ground-engaging brushes driven in rotation about

generally, upright axes and located respectively at a front left corner and a front right

cover of said vehicle;

first and second articulated mechanisms carried by said frame for

mounting arm said first and second brushes respectively for independent movement

in response to contact with an object, each articulated arm comprising:

a first arm mounted for rotation about a first vertical axis

from a position wherein the associated brush is located at a desired position for use

to a second position inboard of said desired use position; and

a second arm pivotally carried by said first arm at a

forward position thereof and mounted for rotation about a vertical axis from said

position of intended use in counter rotation to the rotation of said first arm, thereby

to permit said brush to move laterally of said first arm in a direction counter to the

direction of movement of said first arm when said first arm moves away from said

position of intended use, whereby when both of said first and second arms are

actuated by engagement of the associated brush with an object, said associated brush

moves both inwardly and rearwardly of said frame.

2. The parts of claim 1 further comprising:

a lift linkage mounted to said frame and supporting said first and

second articulated arms; and

a first actuator carried by said frame and adapted to actuate said

lift linkage under control of an operator selectively to raise and lower said first and

second articulated arms.

3. The apparatus of claim 2 further comprising a vacuum shoe having an

open front and bottom carried by said frame to the rear of said brushes to suction

material from said surface, including material moved inwardly by said brushes; and

at least one link connected at one end to said lift linkage and

connected at another end to said vacuum shoe by means of a slot such that as said

actuator lowers said brushes to a use position, said vacuum shoe is lowered to a

working position relative to said surface, and said vacuum shoe is free to rise over

an object on said surface.

4. The apparatus of claim 3 further comprising a support arm connected

at one end to said vacuum shoe and pivotally connected at a distal end to said frame

to support and guide said vacuum shoe and to guide said vacuum shoe into parallel

relation with said surface in its use position.

5. The apparatus of claim 4 further comprising a second actuator

controlled by a user selectively to lift said vacuum shoe to said raised position above

said surface while permitting said brushes to remain in their respective use positions.

6. The apparatus of claim 3 further comprising a latch for each of said

articulated arms for securing an associated articulated arm in a raised position while

permitting said actuator to lower said vacuum shoe to the rise position.

7. The apparatus of claim 5 further comprising a blower:

a first conduit coupled between said vacuum shoe and said

blower for evacuating air and debris from said shoe;

a hopper carried by said frame and having an inlet receiving said

debris and air from said blower;

an air permeable bag in said hopper having an opening coupled

to said inlet of said hopper to receive said debris and air from said fan and filtering

out and retaining said debris;

a filter for fine particles mounted to said hopper to permit air to

pass through said hopper while filtering finer particles therefrom; and

a recirculating conduit for routing recirculating air from within

said hopper to said vacuum shoe.

8. The apparatus of claim 1 further comprising, for each of said articulated

mechanisms:

a first spring biasing an associated first arm outwardly to a use

position while permitting said first arm to pivot inwardly toward the center of said

vehicle; and

a second spring interconnected between associated ones of said

first and second arms to bias its associated second arm to a use position while

permitting said associated second arm to rotate in a direction counter to the

rotational direction taken by said associated first arm in moving away from the use

position thereof in response to engagement with an object.

9. The apparatus of claim 3 further comprising:

a flap pivotally mounted to said vacuum shoe and sized and

arranged to substantially close said inlet opening thereof; and

a third actuator, controlled by a user, for rotating said flap on the

go to adjust the size of said inlet opening for said vacuum shoe, the size of said inlet

opening adjusting the velocity of air into said vacuum shoe through said inlet

opening.

10. The apparatus of claim 9 further comprising a rubber edging strip

attached to the lower edge of said flap. *

11. The apparatus of claim 2 further comprising first and second latches for

selectively coupling said first and second articulating arm mechanisms to said frame

whereby when said first actuator is actuated to lower said lift linkage, said vacuum

shoe will be lowered but said first and second brushes will remain in a raised

position.

12. The apparatus of claim 8 wherein said air permeable bag comprises:

a spun synthetic fiber; said hopper further comprising:

a rear opening and a door hinged to close said rear opening, said

hopper being pivotally mounted for rotation between a use position and a dumping

position; said apparatus further comprising:

a mount extending adjacent said rear opening for receiving

a wire frame to secure a trash bag about said rear opening;

whereby the contents of said air permeable bag may be

transferred directly to said trash bag opening said door, securing said trash bag to

said mount with said wire frame and unsecuring said air permeable bag and rotating

said hopper to said dump position.

13. The apparatus of claim 8 wherein said bag comprises a nylon scrim bag

having a water impermeable lower section adapted to rest on the bottom of said

hopper, whereby said hopper door may be opened and said hopper tilted to the dump

position to discard the contents of said bag under gravity.

14. The apparatus of claim 7 wherein said vehicle includes an outer casing

and said recirculation conduit includes a section passing through a hollow cavity in

said casing, said cavity acting as a plenum for catching heavier debris in the

recirculated air; and further comprising a plug removably coupled to a lower wall of

said cavity for any debris trapped therein under gravity.

15. The apparatus of claim 1 wherein said first arm of each of said first and

second articulated arm mechanisms extends fore-to-aft of said vehicle in the use

position;

said apparatus, further comprising:

a first spring biasing its associated first arm to rotate

outwardly of a center of said vehicle; and

a stop for limiting the outboard rotation of said associated

first arm.

16. The apparatus of claim 15 wherein said second arm of each of said first

and second articulated arm mechanisms supports its associated brush such that the

axis of rotation of said associated brush lies outboard of an extension of its associated

first arm in the direction of travel, thereby permitting said brush to move laterally

outwardly of said associated first arm and simultaneously rearwardly about the

pivotal convection between said first and second arms when said brush encounters

an obstruction.

17. In a vehicle for picking up litter from a surface, said vehicle including

a plurality of ground wheels, a frame and an operator's station, the improvement

comprising;

a blower for generating suction at an input and having an outlet

for delivering forced air;

a vacuum shoe suspended beneath said frame and including a

housing providing an open front and bottom;

a hopper including:

an inlet receiving air from said blower outlet;

a first discharge outlet provided with a filter; and

a recirculating outlet for routing recirculating air received

through said inlet and not exhausted through said first discharge outlet;

first connecting conduit communicating an outlet of said vacuum shoe

with said inlet of said blower, the outlet of said blower coupled in sealing engagement

with said inlet of said hopper;

a body casing having a closed, hollow passage defining a plenum and

communicating with said recirculating outlet of said hopper to receive recirculated

air from said hopper and pass said air through said plenum to an outlet of said

plenum to trap larger particles entrained in recirculated air in said plenum; and

second connecting conduit communicating said outlet of said plenum to

said vacuum shoe to introduce said recirculated air into said vacuum shoe.

18. The apparatus of claim 17 further comprising an over-center hose clamp

having an actuating lever, said hose clamp releaseably attaching said first conduit to

said inlet of said blower.

19. The apparatus of claim 18 wherein said hopper is hinged to said frame

for rotation from a use position to a dump position; said inlet of said hopper being

in releaseable sealing engagement with said outlet of said blower, and said

recirculating outlet of said hopper being in releasable sealing engagement with said

recirculation outlet of said hopper when said hopper is in said use position.

20. The apparatus of claim 17 wherein said vacuum shoe further includes

a flap pivotally mounted above from said inlet opening; and

an actuator under control of a user for adjusting the position of

said flap to adjust the inlet opening of said vacuum shoe thereby to adjust the

velocity of air entering said vacuum shoe and directing said air to enter said vacuum

shoe at a location adjacent the surface being cleaned such that as said flap is moved

to reduce said inlet opening, the velocity of incoming air is increased and said

incoming air sweeps along said surface being cleaned to entrain dirt and smaller

particles therein.

21. The apparatus of claim 17 wherein said body casing includes a bottom

wall having a discharge opening; and further including a removable closure for said

discharge opening of said body casing.