Background of the Invention

1■ Field of the Invention

The present invention relates generally to riding sweepers and, more particularly, is directed to riding sweepers of the type having an air filter and a filter back flushing system.

2. Description of the Prior Art

Riding sweepers of the type having a dumpable hopper for collecting dirt and debris are well known in the art. These systems include a dirt and debris collection hopper and a brush for directing the dirt and debris into the hopper during the travel of the sweeper. In addition to the broom, the sweepers generally incorporate a suction system including a fan, for creating an air flow within the hopper. This creates suction within the hopper to assist in pulling the dirt therein and therethrough.

Such systems have included air filters to protect the fan from excessive dust. Additionally, systems for cleaning the filter without removing the filter have been developed and are known as back flushing systems. These systems utilize pulses of air to clean the filter directed from an air nozzle. The pulses of air are timed and are directed toward portions of the filter to clean a part of the filter during the air pulse. The air pulse is directed against the incoming flow of air such that the particulates collected on the filter fall into the hopper. Generally, such systems utilize several air nozzles in a sequence to continuously clean the filter.

While these systems are generally adequate, they have their shortcomings. These prior art systems do not protect the dirt sensitive components from the dust laden air since the components are generally housed with the engine.

Therefore, it is the object of the present invention to provide an improved dust control system within a riding sweeper.

Summary of the Invention The present invention provides a continuous dust control system within a riding sweeper. The riding sweeper includes a hopper for dirt arid debris collection. The hopper is divided into a dirty chamber and a ciean air chamber. A filter is disposed at an opening between the dirty and clean air chambers. Disposed in the clean air chamber is an air powered filter back flushing system that includes an air manifold, air nozzles, and electronic sequencer for selecting the appropriate air nozzle, valves for directing air from the manifold to the selected nozzle and a pressure switch that measures the pressure in the air manifold.

Once the air manifold reaches a predetermined pressure, the pressure switch sends a signal to the sequences or control module that opens a selected valve to allow the air stored in the air manifold to exit through the selected nozzle. The compressor, powered by a motor that obtains its energy from the on-board battery, then refills the air manifold once the nozzle valve closes. Additionally, the air compressor and motor are located in the clean air chamber. This prevents the • compressor from ingesting dirty air or being impact damaged. The motor and compressor are powered directly from the machine power source. The sequencer is also powered by the 12 volt dc machine power source.

A Brief Description of the Drawings

So that the manner in which the above recited features, advantages, and objects of the present invention are attained and can be understood in detail, a more particular description of the invention, briefly summarized above, may be had by reference to the embodiment thereof which is illustrated in the appended drawings.

It is noted, however, that the appended drawings illustrate only a typical embodiment of the this invention and is therefore not to be considered limiting of its scope, for the invention may admit to other equally effective embodiments. Reference to the appended drawings, wherein: Figure 1 is a perspective view of a riding sweeper that incorporates the present invention;

Figure 2 is a side elevation view of the sweeper of Figure 1 depicted emptying it's debris hopper into a trash container; Figure 3 is an enlarged side view of the hopper of the sweeper showing the continuous dust control in the clean air chamber;

Figure 4 is an enlarged perspective view of the hopper of Figure 3 and partial cut-away showing the placement of the continuous dust control system in the clean air chamber;

Figure 5 is a perspective view of the sweeper of Figure 1 in partial cut-away showing the airflow pattern; and Figure 6 is a schematic of the dust control air and electrical distribution.

Detailed Description

Referring now to Figure 1 there is shown a riding sweeper generally designated 10. The sweeper 10 includes a chassis 12 that is movably retained on a front pair of wheels 14, of which only one wheel is shown, and a rear center wheel 16, shown in Figure 2. The single rear wheel 16 steers or directs the sweeper as the wheel 16 is operably connected to a steering wheel 20. The chassis supports a driver's seat 18 along with various other control mechanisms 22. The sweeper 10 is divided into a front portion 24 that defines a dirt and debris collection hopper in the interior thereof and a rear portion that houses an engine 34, battery 36, and the ■ like (Fig. 5) . The sweeper 10 includes a front brush 28 for assisting and directing debris into the hopper opening.

Referring to Figure 2, the sweeper 10 is shown with the front hopper 24 in it's hinged or opened position ready for emptying the contents thereof into a trash receptacle 30. Once the hopper 24 is full, the sweeper 10 is positioned next to the trash receptacle 30 where the front hopper pivots for unloading of the contents therein.

With particular reference to Figure 5, the sweeper 10 is shown in partial cut-away view. The sweeper 10 is driven by a typical engine 34 or motor that includes a 12 VDC battery 36 both of which are disposed in a cavity 32 within the rear housing 26. The motor is operably connected (not shown) to the rear wheel 16 for driving the same.

The hopper 24 has an opening 40 adjacent to which a longitudinal brush 38 is disposed. The longitudinal brush 38 is rotatable and driven by the sweeper power source. As the sweeper 10 moves in the forward direction, the brush 38 gathers and pushes the dirt and debris into hopper 24 via the opening 40. The

main hopper 24 is divided into a dirty or debris collection chamber 44 and a clean air chamber 56. The dirty chamber 44 is further divided into a primary collection chamber 45 and secondary collection chamber 52 by walls 48 and 50. The primary collection chamber 45 is for the collection of large debris while the secondary collection chamber 52 is for the collection of smaller debris and particulates.

Disposed over an opening between the secondary chamber 52 and the clean air chamber 56 is a filter 58. Disposed within the clean air chamber adjacent to the filter 58 is a continuous dust control system generally designated 64. The continuous dust control system 64 includes, among other components described in particular hereinbelow, an air reservoir 70 or manifold disposed adjacent to the filter 58, a motor 68 that is operatively connected to an air compressor 66, nozzles 76, 78, 80, a pressure sensor/switch 94, a 12 VDC controller/sequencer 92, and various valves. A blower or a fan 6.0 is also disposed in the sweeper 10 and is used to provide the suction through the hopper system to assist the collection of. dirt and debris. When the sweeper 10 is operating, the fan 60 causes an air flow or suction to exist within the hopper 24 as designated by the air flow arrows. Once the air or debris enters the hopper it follows the tortuous chambers eventually into the filter 58. An air filter cover 82 directs the filtered air out towards the continuous dust control system and through the fan and duct work 62 of the sweeper to thereafter push the clean air out the rear of the sweeper.

With reference to Figures 3 and 4, the continuous dust control system 64 will be described with particularity. As indicated above, the filter 58 is disposed over the opening between the secondary chamber

56. The filter 58 is releaseably affixed over the opening in a known manner. Disposed over the filter 58 is a hood or cover 82 which is generally triangular shaped and which includes three partitioned areas 88, 89, 90 for directing the flow of air through the partitioned areas 88, 89, 90 and out into the clean air chamber. The cover 82 is tapered closed at one end and opened at the other. The cover 82 is secured over the filter by two removable tiebars 84, 85 coupled to the sweeper frame and which are bolted thereto and extend thereacross .

Additionally, the cover includes a first flange 86 that couples to a second flange 87 at the side of the hopper 24.

The compressor 66 is mounted by brackets 69 adjacent to the air reservoir 58 and is in communication therewith via a tube 67. The compressor continuously supplies the reservoir 70 with air. Disposed on the air reservoir 58 and in communication therewith are three air nozzles and pneumatic valves 76, 78, 80. A pressure sensor 94 is also coupled to the air reservoir 58 and electrically connected to an electronic sequencer or controller 92 for sensing the pressure of the air within the reservoir 70 and sending a signal to the controller 92 for selecting and opening the appropriate nozzle in which to direct the blast of air.

Referring now Figure 6, the operation of the dust control system 64 will now be described. The motor 68 is connected to the sweeper power source, battery 36, that drives the compressor 66 via a pulley 72 and belt 74 (Fig. 4) . The compressor 66, being a Thomas Pneumotive SGH series, is connected by tubing 67 to the air reservoir or manifold 70. The air reservoir 70 stores the compressed air for eventual pulsing of air through a respective nozzle 76, 78, 80, which directs the pulses of air through the respective chambers 88, 89, and 90 of the hood 82. This directs the blast of air through the

portions of the filter 58. A pressure sensor 94, such as a Suco 016E series, is coupled to the air reservoir 70 for sensing when the air reservoir has reached a predetermined pressure level. When this predetermined pressure level is reached, the pressure switch 94 sends a signal to the control module or sequencer 92 through electrical line 112. The control module or sequencer 92 determines which of the three nozzles, 76, 78, and 80, to fire. Usually the sequence is a predetermined succession of nozzles.

The continuous dust control unit 64 further includes solenoid controlled air valves 96A, 96B, and 96C, such as a Humphrey 310 series valve, one for each of the nozzles 76, 78, 80. Each solenoid activated valve, 96A, 96B, and 96C, is electrically connected to the control module 92 by respective electrical lines 118, 116, and 114. Further, the solenoid controlled air valves 96A, 96B, and 96C are coupled to the air reservoir via conduits 119, 124, 122, and 120. Thus, as the pressure sensor indicates that there is sufficient air pressure within the air reservoir 72 to fire a pulse of air, the control module sends a signal to the respective solenoid controlled valves 96A, 96B, 96C to trigger pneumatic valves 100, 102, and 104, such as a Goyen model 2561, that are operably connected to nozzles 76, 78, and 80. The pneumatic valves 100, 102, and 104 open when a pulse of air is received through a respective line 200, 201, or 202, which is accomplished when the respective solenoid controlled valve is actuated. The air pressure from the manifold 70 is then caused to flow through conduits 106, 108, or 110 into the pneumatic valve 100, 102, or 104 which then flows out the respective nozzle. In this manner, the nozzles are caused to direct the pulse of air into the filter.

What has been described hereinabove is a continuous dust control system wherein the compressor for the air reservoir and thus the back flushing air always pumps clean air into the air reservoir since it is located in the clean air chamber of the hopper. A pressure switch determines when the air reservoir is ready for discharging wherein valves trigger the nozzles once the air reservoir reaches the predetermined level. A 12 VDC electronic sequencer or timer chooses the valve and thus the nozzle to fire the pulse of air.

Additionally, the machine power source drives the compressor motor and sequencer.