DEVICE FOR SWEEPER UNITS

Abstract: Device for sweeper units of the type which comprises an elevator in the shape of an inclined chute (16, 18). Carriers or brooms (28) which run in an endless path, are at one end of the path in contact with the ground surface which is to be cleaned, and transport refuses and the like upwards along the bottom (16) of the chute from the lower transverse edge of the chute. An interspace which exists between the lower transverse edge of the chute and the ground surface is, according to the invention, bridged over thereby that an endless, flexible sheeting (40) passes over, and substantially covers, the bottom (16) of the chute. After the passage over the bottom of the chute, the sheeting runs downwards ahead of the chute viewed in the direction of travel (22) or the sweeper unit (10) and contacts said ground surface (20), whereby said interspace between the lower transverse edge of the chute and the ground surface is bridged over by said sheeting (40).

Description: The present invention relates to a device for street sweeper units of the type which comprises an elevator in the shape of an inclined chute along the bottom of which carriers operating in an endless track transport refuses or the like upwards from the lower end of the chute. Such a device is known, for instance, from DE-C-376 016 or from SE-B-335 747. The carriers which usually have the shape of brooms, bear against the ground surface and sweep the refuses in the direction of travel of the unit towards the chute located ahead of the elevator, wherein the refuses are transported by the carriers upwards to a collecting vessel, which is located in attachment to the upper edge of the chute inclined in the direction of travel of the unit. The lower transverse edge of the chute must necessarily be located at a distance from the ground surface in order to prevent it during drive of the unit from striking against irregularities in the ground. A problem in connection with the described type of sweeper is constituted thereby that some portion of the refuses is thrown onwards by the carriers or brooms between the lower transverse edge of the chute and the ground surface and thus does not follow with the brooms upwards into the chute. For solving this problem it is known from SE-B-335 747 to mount adjacent the lower transverse edge of the chute a freely rotatable sweeping roll which is intended to bridge over the interspace between the transverse edge and the bottom or the ground surface which is being swept. In this way the sweeping roller guides the refuses up into the chute in cooperation with the carriers or brooms of the elevator so that the lower edge can be applied at a sufficiently great distance from the ground surface for preventing it from becoming damaged when the sweeper unit is advanced. Even with this known device one is dependent thereon that the distance between this lower transverse edge of the chute and the ground plan does not undergo too great changes during drive or by wear on the sweeping roller. The main object of the present invention is to produce a device for sweeper units of the kind described above which eliminates the stated problem and in this respect follows another way than the known technique. This object is attained, according to the invention, thereby that the device has received the characteristic features stated in the following claims. The invention will be described nearer hereinafter in connection with the drawing. Figure 1 shows, partly diagrammatically and partly in a section, a lateral view of a sweeper unit with an elevator. Figure 2 shows a view similar to that of Fig. 1 of a modified embodiment. In the drawing, there is indicated in Figures 1 and 2 with dot and dash lines a sweeper unit 10, which e.g. may be supported by supporting arms 12 also known by dash and dotted lines on a tractor or similar machine (not shown). The sweeper unit 10 is of a type known per se having rotating brooms, for example (not shown), which sweep together the refuses on the ground surface into a windrow, which thereupon is taken up by the elevator 14 of the sweeper unit, as will be described nearer more below. Such a sweeper unit is shown in, for example, SE-B-335,747, to which reference is made for a more general description of the function of the sweeper unit and the rotating brooms. The sweeper unit comprises a chute with a flat bottom 16 and upraised side edges 18. The chute is applied so in the unit 10 that it extends from a lower transversal edge, which, as shown in the position of use of the unit is located at some distance above the ground level 20 which shall be swept, obliquely upwards in the direction of travel of the unit and which is marked by the arrow 22, to a position where the upper end of the chute 16 is positioned in attachment to a refuses collecting vessel 24 disposed in the unit 10, into which vessel the refuses drop down from the upper transverse edge of the chute 16. The transport of the refuses along the chute is effected by means of the said elevator 14 which comprises an endless belt 26, onto which carriers in the shape of brooms 28 are disposed at suitable mutual distance over the length of the belt. The belt 26 is carried by a pair of turning rollers 32 and 34, journalled adjacent the ends of the chute on a frame 30, of which the upper roller 32, for example, is driven by a motor (not shown), such as a hydraulic motor, for example. The chute 16 is supported at the frame 30 of the elevator by means of two supporting members 36, which preferably are made resilient so as to cause the chute 16 to be loaded with a predetermined preload in a direction towards the frame 30 of the elevator. A bar 38 is fixed in between the frame 30 and each of the side edges of the chute 16 in order to stabilize the chute in its longitudinal extension. The shown and described resilient supporting of the chute 16 and the elevator 14 in relation to each other results in that the carriers or brooms 28 remain always in contact with the bottom of the chute 16 even when the brooms 28 become worn in use. The above described elevator device 14 operates, as has been mentioned, in such a manner that the refuses in the direction of travel 22 of the unit are swept forwards and upwards in the chute and transported further by the brooms 28 to the upper transverse edge of the chute, where the refuses fall down into the collecting vessel 24, as is indicated in the drawing. For bridging over the indispensible interspace between the lower transverse edge of the chute 16 and the ground surface 20, there is disposed, according to the invitation, a soft, flexible sheeting 40, which runs in an endless loop over the bottom 16 of the chute and substantially covers the same, and from the upper transverse edge in downward direction towards the ground plan 20 for bearing against the same and thereupon again to the lower transverse edge of the chute and up to the bottom of the chute. As mentioned, the sheeting 40 is soft, flexible and pliable and manufactured of, for example, rubber or some other material having the desired properties as, for example, rubber-like plastic material, and is positioned loosely guided over the bottom of the chute, which for this purpose has edges belled with a soft radius. In order to achieve that the upper transverse edge of the chute is located above the collecting vessel 24, the sheeting 40 is conducted over a fixed bending place 42, which may be constituted by a transversal rod or the like, for example. The sheeting 40 moves together with the carriers or brooms 28 of the elevator 14 by conveying through friction the sheeting in the direction of transport of the refuses, as is indicated by the arrows in Figure 1. Hereunder the sheeting 40 overbridges the interspace between the lower transverse edge of the chute and the ground plan 20 and thus prevents refuses from becoming slung in the direction of sweep ahead of the chute, but instead are caused to follow up to the bottom 16 of the chute between the sheeting 40 and the broom 28. In the embodiment according to Figure 2, where the parts common with the embodiment of Figure 1, have the same reference numerals, it is shown how the sheeting 40 can be provided with transversal fillets or projections 44, which ensure still more that the sheeting 40 is conveyed with the brooms 28 over the bottom 16 of the chute. In this connection it is obvious that the projections or fillets 44 which engage the carriers 28 of the elevator 14, need be positioned with such spacing only that a new fillet 44 will engage a broom 28 at the lower transverse of the chute simultaneously as the preceding fillet or elevation 44 leaves the chute at the upper transverse edge thereof, even though the projections 44 may be positioned more densily if so should be desired. It becomes evident from the aforesaid that the device made according to the invention with a soft sheeting which bridges over the interspace between the chute of the elevator 14 and the ground surface 20 complies with the object stated above in the introduction. Thanks to the feature that the sheeting 40 is soft, flexible, pliable and in unstressed position lies down loosely over a considerable portion of the ground surface 20 and thereby becomes independent of the spacing between the chute and the ground surface as well as possible unevenness in the latter. The refuses do not obtain any possibility of passing past the lower transverse edge in the direction of travel 22, but stick fast on the sheeting and are carried along by the same and the brooms 28 of the elevator upwards on the chute to the discharge end thereof. Obviously, the invention is not limited to the shown and described embodiment, but may be varied in a plurality of aspects with the scope of the idea basic for the same, as defined in the appended claims.

Claims: 1. Device for sweeper units of the type comprising an elevator (14) in the shape of an inclined chute (16, 18), along the bottom of which a carrier (28) working in an endless track transports refuses and the like upwards from the lower end of the chute, characterized in that endless, flexible sheeting (40) substantially covering the bottom (16) of the chute extends over the chute and downwards ahead of the chute seen in the direction of travel (22) of the sweeper unit (10) to abutment to the ground surface (20) over which the sweeper unit (10) passes so that possible interspaces between the lower transverse edge of the chute and the ground surface are bridged over. 2. Device according to claim 1, characterized in that the sheeting (40) has such a length that a substantial portion of said sheeting comes into contact with the ground surface (20) ahead of the elevator seen in the direction of travel (22) of the unit. 3. Device according to either of claims 1 or 2, characterized in that the sheeting (40) is guided loosely over the chute and caused to move over the bottom (16) thereof and along its endless path by frictional engagement with carriers (28) of the elevator. 4. Device according to claim 3, characterized in that the chute (16, 18) and the carriers (28) of the elevator are resiliently loaded relatively to each other for achieving the said frictional engagement. 5. Device according to either of claims 3 or 4, characterized in that the path of the sheet is formed by fixed bending places (16, 42). 6. Device according to claim 5, characterized in that the bottom (16) of the chute has belled lower and upper transverse edges in order to constitute two of said fixed bending places. 7. Device according to any of the claims 1 through 6, characterized in that the sheeting is provided with transversal fillets or elevations (44) devised to engage the carriers (28) of the elevator (14) when the sheeting moves over the bottom (16) of the chute. 8. Device according to any of the claims 1 through 7, characterized in that the carriers (28) of the elevator (14) in a manner known per se comprise a series of brooms (28) disposed with interspaces on an endless belt (26). 9. Device according to any of the claims 1 through 8, characterized in that the sheeting (40) is soft, flexible and pliable, e.g. of a material as rubber or plastic with corresponding properties.

Inventors: SANDSTROEM, HENRY, Sandström, Henry
Applicants: SANDSTROEM, HENRY
Application year: 1987
Main classification: E01H1
IPC codes: E01H1