BRIEF DESCRIPTION OF THE DRAWING
FIG. 1 is a schematic side view of a walk-behind sweeper.
FIG. 2 is a schematic section illustration of the walk-behind sweeper of FIG. 1.
FIG. 3 is a schematic side view of one embodiment of the sweeper.
FIG. 4 is a schematic side view of another embodiment of the sweeper.
DESCRIPTION OF THE PREFERRED EMBODIMENTS
The sweeper 1 illustrated in FIG. 1 has a handle frame 2 on which two handles 3 are attached. By means of the handles 3, the sweeper 1 can be moved across the floor by the operator. The sweeper 1 has two front wheels 4 and two rear wheels 5 of which only one is illustrated, respectively, in FIG. 1. The two front wheels 4 and the two rear wheels 5 are not powered. The sweeper 1 has a leading sweeping roller 6 that, relative to the travel direction 48 of the sweeper 1, is arranged in front of the two front wheels 4; also provided is a rear sweeping roller 7 that, relative to the travel direction 48, is arranged between the front wheels 4 and the rear wheels 5. The sweeper 1 has a dirt collecting container 8. Above the rear sweeping roller 7 there is a baffle or deflector 9 that deflects the swept-up material that has been swept up by the sweeping rollers 6, 7 to the dirt collecting container 8. The swept-up material is conveyed into a dirt collecting chamber 50 that is provided in the dirt collecting container 8. A motor housing 10 is arranged behind the dirt collecting container 8 relative to the travel direction 48. The motor housing 10 has exit openings 18 for cooling air.
FIG. 2 shows a schematic section illustration of the sweeper 1. As shown in FIG. 2, a drive motor configured as an internal combustion engine 11 is arranged in the motor housing 10. The internal combustion engine 11 has a cylinder 21 provided with cooling ribs 12 on its exterior. The internal combustion engine 11 is an air-cooled single cylinder motor, particularly a two-stroke engine. The internal combustion chamber 11 drives the crankshaft 14 in rotation. Fixedly connected to the crankshaft 14 is a fan wheel 13 that conveys cooling air to the cylinder 21. The cooling air flows in the direction of arrows 25 across the cooling ribs 12 of the cylinder 21. The fan wheel 13 has a vacuum side 15 where, as a result of the rotation of the fan wheel 13, a vacuum is generated. Advantageously, the fan wheel 13 takes in the cooling air stream in the axial direction of the crankshaft 14 and conveys the cooling air in the radial direction outwardly. At the vacuum side 15, the fan wheel 13 takes in the cooling air in the direction of arrow 24.
The vacuum side 15 of the fan wheel 13 is connected by a cooling air passage 22 to the clean side 23 of the filter 16. The filter 16 is arranged at the topside 45 of the dirt collecting chamber 50. The filter 16 is arranged in a filter housing 19; the filter housing 19 and the dirt collecting container 8 are configured as a monolithic or unitary part. The filter housing 19 is dosed by a cover 49. The filter 16 is accessible for maintenance work through cover 49. The motor housing 10 has an intake opening 36 through which additional cooling air from the surroundings is taken in. At the intake opening 36 a slide 37 is arranged that is movable in the direction of arrow 38. By means of the slide 37, the open cross-sectional area of the intake opening 36 and thus the portion of cooling air stream taken in from the surroundings are adjustable. It can also be provided that means for adjusting the cooling air stream taken in from the working area are arranged on the cooling air passage 22. The intake opening 36 is schematically illustrated in FIG. 2. Instead of slide 37, other means for changing the open cross-sectional area are possible. The intake opening 36 can advantageously be arranged laterally or on the topside of the motor housing 10 facing the operator.
The crankshaft 14 drives by means of gear 28 the front sweeping roller 6 and the rear sweeping roller 7 in opposite directions. The front or leading sweeping roller 6 is driven in a rotational direction 26 that, relative to the floor, is opposite to the travel direction 48. The rear sweeping roller 7 is driven in a rotational direction 27 that is opposite to the rotational direction 26 and, on the floor, is oriented in the travel direction 48. It can be provided that only one of the sweeping rollers 6, 7 is driven by the gear 28 and the movement of the other sweeping roller 7, 6 is coupled, for example, by means of a belt drive or the like to the driven sweeping roller. In this way, the internal combustion engine 11 drives in rotation both sweeping rollers 6, 7.
The two sweeping rollers 6, 7 convey the swept-up material into the interstice formed between the two sweeping rollers 6, 7 and upwardly. The swept-up material is conveyed in accordance with the overthrow principle, whose conveying action is indicated by arrow 20, into the dirt collecting chamber 50. The swept-up material is guided by the deflector 9 into the dirt collecting chamber 50.
As shown in FIG. 1, in the travel direction 48 between the two sweeping rollers 6 and 7 a working area 17 of the sweeper 1 is provided from where the sweeping rollers 6, 7 convey the swept-up material. From the working area 17 of the sweeper 1, the cooling air for the internal combustion engine 11 is taken in by the fan wheel 13 through the cooling air passage 22, the filter 19, and the dirt collecting chamber 50. In this way, the dust control during sweeping is improved. Conveying of the swept-up material into the dirt collecting chamber 50 is assisted by the cooling air stream. The cooling air passage 22 is formed in the dirt collecting container 8. The cooling air passage 22 and the dirt collecting container 8 are formed as a unitary part. In this way, no additional components are required for providing the flow connection of the working area 17 to the intake side 15 of the fan wheel 13.
One embodiment of the sweeper 30 is illustrated in FIG. 3. The configuration of the sweeper 30 corresponds essentially to that of the sweeper 1. Identical components are referenced by the same reference numerals in the drawings.
The internal combustion engine 11 of the sweeper 30 is arranged above the dirt collecting container 8 in the motor housing 40. The motor housing 40 can be supported on a frame 39 of the sweeper 30. The motor housing 40 is connected by connecting socket 31 to the working area 17 of the sweeper 30. The flow connection is realized by the dirt collecting chamber that is provided in the dirt collecting container 8. The filter 16 is arranged at the exit of the dirt collecting container 8 where the cooling air stream that is taken by the fan wheel 13 in the direction of arrow 34 exits from the container 8. The filter 16 is arranged on the topside 45 of the dirt collecting chamber 50.
A cooling air passage 32 for the conveyed cooling air is formed within the connecting socket 31 through which the entire cooling air is taken in. However, means for adjusting the cooling air portion that is taken in from the working area by means of the connecting socket 31 can be provided. An additional intake opening for taking in cooling air from the surroundings can be provided. The connecting socket 31 provides a mechanical connection between the motor housing 40 and the dirt collecting container as well as a flow connection between the intake side 15 of the fan wheel 13 and the dirt collecting chamber 50. The fan wheel 13 conveys the cooling air, taken in as indicated by arrows 34, across the cooling ribs 12 of the internal combustion engine 11 in the direction of arrow 35. The cooling air stream can exit the motor housing 40 through exit openings 18.
FIG. 4 shows another embodiment of the sweeper 46. The sweeper 46 corresponds essentially to the sweeper 1 of FIGS. 1 and 2. Identical reference numerals identify identical components. As a drive motor, the sweeper 46 has an electric motor 41 whose drive shaft 44 drives the fan wheel 13 and the sweeping rollers 6 and 7. The electric motor 41 is arranged in the cooling air stream that is conveyed by the fan wheel 13 and illustrated by arrows 24 and 25. The energy supply for the electric motor 41 is provided by battery 42 that is configured as a rechargeable battery. The battery 42 is also arranged in the cooling air stream conveyed by the fan wheel 13 so that the electric motor 41 as well as the battery 42 in operation of the sweeper are cooled by the cooling air stream. In order to enable in a simple way recharging of the battery 42, a connector 43 is provided that is accessible from the exterior of the motor housing 10 and is connected to the battery 42. It can also be provided that the battery 42 is removed from the housing 10 for recharging.
The specification incorporates by reference the entire disclosure of German priority document 10 2006 037 452.5 having a filing date of 10 Aug. 2006.
While specific embodiments of the invention have been shown and described in detail to illustrate the inventive principles, it will be understood that the invention may be embodied otherwise without departing from such principles.
Patent Application
20080034516
