[0052]As shown in FIGS. 1-5, a first embodiment 25 of a vehicular sweeping machine includes frame 26, engine compartment 27, operator's cab 28, broom assembly 29, broom conveyor 30 and articulating discharge conveyor 31. Contained within engine compartment 27 is an engine (not shown) that provides power for driving rear wheels 32 of the machine, as well as for operating the broom assembly and other components of the vehicular sweeping machine. Steering of machine 25 is accomplished by means of a conventional steering assembly operating through front wheels 34. When machine 25 is driven in forward sweeping direction “D”, it is desirable that the bottom of broom assembly 29 sits down on the sweeping surface to create a stable seal against the roadway. Such stability is provided by mounting the broom assembly 29 on frame 26 by means of a four-link arrangement comprised of a pair of lower links, right lower link 36 and left lower link 38, and a pair of upper links including right upper link 40 and a left upper link (not shown) that is mounted parallel to right upper link 40 on the left side of machine 25. Furthermore, a plurality of linear actuators are provided in this embodiment of the invention, including front linear actuator 42 and rear linear actuator 44, for raising and lowering the broom assembly with respect to the frame. In some embodiments of the invention, a pair of front linear actuators are provided, one on each side of the broom assembly, along with a pair of rear linear actuators (also located on opposite sides of the broom assembly). In other embodiments of the invention, only one or a plurality of rear linear actuators (such as rear linear actuator 44) will be required. Thus, for example, FIGS. 23 and 24 illustrate an alternative embodiment of a portion of vehicular sweeping machine 125 that is similar in many respects to vehicular sweeping machine 25 of FIGS. 1-5. In this embodiment of the invention, however, a single linear actuator 144 is mounted in a diagonal configuration between frame 126 and broom assembly 129.
[0053]Broom assembly 29 includes broom enclosure 45 and a broom comprising a generally cylindrical broom tube 46 with attached bristles that is adapted to rotate about a generally horizontal axis within the broom enclosure. The drawings show brooms having different bristle configurations and/or in different states of bristle wear. Thus, for example, FIGS. 6, 18 and 19 show broom tubes 46 with a plurality of short densely packed bristles 48 attached thereto, whereas FIGS. 2, 4, 7, 10, 11, 15 and 20-24 show broom tubes 46 with a plurality of longer, more widely-spaced bristles 50. It is important to realize that as the longer spaced bristles 50 of the embodiments shown in FIGS. 2, 4, 7, 10, 11, 15 and 20-24 wear, they may be reduced in length to a length similar to that of bristles 48 shown in FIGS. 6, 18 and 19.
[0054]When machine 25 is driven in forward sweeping direction “D”, milling chips, dust and other material on the roadway will enter broom assembly 29 from its front side. The efficiency of the sweeping operation is facilitated by the four-link mounting arrangement of the broom assembly to the frame, and the linear actuator(s) associated therewith that may be employed to raise and lower the broom assembly with respect to the roadway. More particularly, this mounting arrangement comprises right upper link 40, which is pivotally mounted at one end to frame 26 and at the other end to an upper right position on broom assembly 29. Similarly, a left upper link (not shown but substantially identical to right upper link 40) is pivotally mounted at one end to frame 26 and at the other end to an upper left position on broom assembly 29 (opposite to the upper right mounting position of right upper link 40). Right lower link 36 is pivotally mounted at one end to frame 26 and at the other end to a lower right position on broom assembly 29, and left lower link 38 is pivotally mounted at one end to frame 26 and at the other end to a lower left position on broom assembly 29. Front linear actuator 42 and rear linear actuator 44 are each mounted between the broom assembly and the frame and are adapted to raise and lower the broom assembly with respect to the frame, and consequently, with respect to the roadway surface. In some embodiments of the invention (such as the embodiment illustrated in FIGS. 23 and 24), either or both of the front and rear linear actuators is mounted with one end pivotally attached to the frame on one side of the machine and the other end pivotally attached to the broom assembly on the opposite side of the machine. In other embodiments of the invention, the linear actuators may be mounted generally vertically in pairs with one end attached to the frame and the other end attached to the broom assembly. In these embodiments, one front linear actuator and one rear linear actuator are mounted generally vertically on one side of the machine and one front linear actuator and one rear linear actuator are mounted generally vertically on the other side of the machine. In addition to facilitating a sweep seal of the roadway, the mounting assembly comprising the four-link mounting arrangement and one or more linear actuators makes it easier to load the sweeping machine on a flatbed truck for transport to and from the sweeping site.
[0055]The broom may be rotated about a generally horizontal axis in a counterclockwise direction as viewed in FIG. 2, or in a clockwise direction as viewed in FIGS. 4, 6, 7, 10, 23 and 24. Because of the configuration of the broom enclosure, rotation of the broom in either direction causes much of the material on the roadway to be deposited onto lower end 52 of broom conveyor 30 for transport to discharge conveyor 31. However, some of the material from the roadway may be trapped in the bristles of the broom, and some material may be ejected away from the broom towards the top and/or rear of the broom enclosure. Such material is contained by the preferred broom enclosure which comprises a moldboard assembly having two layered moldboards arranged at the rear end of broom assembly 29 in such a way as to form a labyrinth seal that will trap material inside the broom enclosure. An outer moldboard comprises generally rigid upper panel 54 and generally rigid lower panel 56 that are joined together at hinge 58. An inner curved moldboard 60 is attached at the top of upper panel 54 of the outer moldboard by hinge 62. Upper panel 54 of the outer moldboard has a pair of integral side panels, including side panel 64 shown in FIGS. 8 and 9, and inner moldboard 60 also has a pair of integral side panels, including side panel 66 shown in FIGS. 8 and 9. The side panels slide across the end gates of the broom enclosure, including right end gate 68 shown in FIGS. 8 and 9, to insure that the broom is always enclosed by the end gates and moldboard assembly of the broom enclosure and by the underlying road surface when the sweeping machine is being operated. The combination of these features and the relative placement of the two moldboards causes the bristles of the broom to direct and contain the material within the broom enclosure, regardless of the length of the bristles of the broom, as can be seen by comparing FIGS. 6 and 7. Material that is ejected away from the broom towards the top and/or rear of the broom enclosure is directed by the moldboards down towards the roadway surface, so that it can be swept by the bristles of the broom onto lower end 52 of broom conveyor 30. The arrangement of the inner and outer moldboards is such that as the bristles of the broom wear and become shorter, thereby decreasing the sweeping diameter of the broom (or as brooms of different sizes are employed), the moldboards will always create a sloped surface that sheds material onto the roadway, as shown by the arrows in FIGS. 8 and 9, and will prevent the buildup of material within the broom enclosure behind the broom. The moldboard assembly is configured and arranged to automatically adjust to accommodate brooms having various bristle lengths. As shown in FIG. 7, the bristles 50 of a broom with a large sweeping diameter will contact the inside surface of inner moldboard 60 in such a way that the inside angle between upper panel 54 and lower panel 56 of the outer moldboard (i.e., the inside angle between upper panel 54 and lower panel 56 at hinge 58) is larger than in the configuration of FIG. 6 wherein contact of the bristles 48 of a broom with a smaller sweeping diameter with the inside surface of the inner moldboard causes the inside angle between upper panel 54 and lower panel 56 of the outer moldboard to be smaller. Thus, as shown in FIGS. 6-9, lower end 69 of inner moldboard 60 remains in contact with the bristles of the broom regardless of the length of such bristles.
[0056]The operation of broom assembly 29 is rendered more efficient than that of conventional broom assemblies by a material presentation system comprising structures that control or condition material to be swept by the broom onto broom conveyor 30 for transport to discharge conveyor 31. Preferably, these structures serve to move material into contact with the broom in the form of a windrow that is located generally in front of the center of the broom assembly. The arrows in FIGS. 10 and 11 indicate the relative movement of material to be swept as vehicular sweeping machine 25 moves in the forward sweeping direction, i.e., in a direction towards the left side of the page on which FIG. 10 is displayed and in a direction towards the bottom of the page on which FIG. 11 is displayed. Certain of the novel structures of the material presentation system of broom assembly 29 serve to direct material to the broom and to prevent material from passing outside of the end gates of the broom enclosure. Thus, as shown in FIG. 11, right end gate 68 and left end gate 70 are located on opposite sides of broom tube 46, and knock-down blade 72 (also shown in FIGS. 10, 12 and 16) is located at the front of the broom assembly and somewhat above the surface of the roadway. The knock-down blade is adapted to control the height of the material on the roadway that is contacted by the broom. As shown in FIGS. 10, 11 and 16, knock-down blade 72 comprises a generally vertical face that is located at the front of broom assembly 29 below lower end 52 of broom conveyor 30. Attached to knock-down blade 72 is preferred V-shaped rake 73, best shown in FIG. 16, which is comprised of a plurality of spring steel tines 74 that are flexibly mounted to a pair of rake rods 75 in such a fashion that the tines will flex as they encounter material on the roadway surface. As shown in FIGS. 11 and 16, V-shaped rake 73 is preferably formed from two equal-sized rake portions (each comprising a rake rod and a plurality of tines) that meet at an obtuse angle φ that is preferably equal to about 150°.
[0057]The knock-down blade regulates the height of material that is presented to the V-shaped rake, and the rake, which is located so as to contact the surface of the roadway, is adapted to pull up any material stuck to the roadway surface and to prevent material with relatively large particle size from contacting (and possibly damaging) the lower side of the belt on broom conveyor 30. The V-shaped rake also evens the height of the material across the width of the broom assembly and urges it into the restricted space between a pair of foot assemblies located behind the rake.
[0058]Left foot assembly 76 has a horizontally disposed left bottom panel 77 (shown in FIG. 11), an angled left lower wall 78 (shown in FIG. 12) and an angled left upper face 79 (shown in FIGS. 12, 17 and 18) that is adjacent to the left side of lower end 52 of broom conveyor 30. Preferably, the angle of left upper face 79 is generally the same as that of lower end 52 of broom conveyor 30 with respect to the roadway. Attached to the outside edge of bottom panel 77 is left foot ski 80, which is adapted to slide along the roadway as sweeping machine 25 is operated. Similarly, right foot assembly 81 has a horizontally disposed right bottom panel 82, an angled right lower wall 83 and an angled right upper face 84 that is adjacent the right lower end of broom conveyor 30. Preferably, the angle of right upper face 84 is generally the same as that of lower end 52 of broom conveyor 30. Attached to the outside edge of bottom panel 82 is right foot ski 85, which is adapted to slide along the roadway as the machine is operated. The foot assemblies are positioned on the broom assembly so that a small gap will be created between the bottom panels and the roadway surface, which allows a minimal amount of material to pass under the bottom panels, while the major portion of the material is redirected to the center of the broom assembly by rake 74 and foot assemblies 76 and 81. Any material that passes under the bottom panels is retained within the broom enclosure by end gates 68 and 70.
[0059]In order to facilitate the removal and replacement of a broom core, at least one of the end gates of the broom enclosure is mounted so as to pivot about a generally vertical hinge towards the front of the broom assembly. Thus, right end gate 68 is pivotable from the closed position shown in FIG. 17 to the open position shown in FIGS. 18 and 19. In addition, right side head cover 86 is also part of the preferred broom enclosure and is attached with a generally horizontal hinge, so that it can be opened to allow the broom to be removed from the side of the broom enclosure. Thus, right side head cover 86 is pivotable from the closed position shown in FIG. 17 to the open position shown in FIG. 18. Broom tube 46 is mounted between a pair of hubs, including drive hub 87 on the left side, the generally conical inner broom engaging portion of which is shown in FIGS. 12-15 and 19, and idler hub 88, the generally conical inner broom engaging portion of which is shown in FIGS. 12-15 and the outer portion of which is shown in FIGS. 17-19. Drive hub 87 comprises or is attached to a rotary actuator that is adapted to rotate the broom about its axis of rotation. Idler hub 88 is attached to right hub mount arm 89, and drive hub 87 is attached to left hub mount arm 90, with each hub having an inner portion that extends through the hub mount arm for engagement with one of the ends of the broom tube, as best shown in FIGS. 12-15 and 17-19. Of course, it is contemplated within the scope of the invention that the drive hub could be attached to a right hub mount arm and the idler hub attached to a left hub mount arm. It is also contemplated within the scope of the invention that both hubs could be driven by or comprise rotary actuators.
[0060]Right hub mount arm 89 and left hub mount arm 90 are also mounted to the rear of the broom enclosure by a plurality of outer tubes 92 and inner telescoping tubes 94. In the embodiment of the invention shown in the drawings, each of the outer tubes is attached to left hub mount arm 90 and to a plurality of brackets 95 on the rear of the broom enclosure. Each of the inner telescoping tubes 94 has a fixed end that is attached to right hub mount arm 89 and a free end that is adapted to slide within the outer tube 92 with which it is associated. The free ends of the inner telescoping tubes move into and out of the outer tubes by the action of a linear actuator such as actuator 96 which is attached between the broom enclosure and right hub mount arm 89. Thus, as may be understood by comparing FIGS. 17 and 18, when right side head cover 86 is pivoted to the open position and right end gate 68 is pivoted to the open position, right hub mount arm 89 with attached broom tube 46 can be moved outwardly from the side of the broom assembly, as shown in FIGS. 18 and 19. This will disengage broom tube 46 from left hub 87. Then broom tube 46 can be disengaged from right hub 88 and removed from the machine. A new broom can then be installed by reversing this process.
[0061]FIGS. 20-22 illustrate additional features of a preferred embodiment of the invention. As shown therein, the hub (not shown) associated with right hub mount arm 89 can be withdrawn from broom tube 46 by moving right hub mount arm 89 outwardly from the side of the broom assembly. Right hub mount arm 89 may then be then rotated about an axis through the center of inner telescoping tube 94, as show in FIG. 22, to make it easier to remove broom tube 46 from the hub (not shown in FIG. 22) associated with left hub mount arm 90. After the broom tube is disengaged from the hubs on both sides, it can be easily removed from the machine. A new broom can then be installed by reversing this process.
[0062]The invention thus provides a fully-enclosed broom assembly that can more efficiently be operated to remove material milled by a milling machine from a roadway. Furthermore, even though the broom assembly is fully-enclosed, it can be manipulated with common tools and in a short period of time to allow for removal and replacement of the broom.
[0063]Although this description contains many specifics, these should not be construed as limiting the scope of the invention, but as merely providing illustrations of the presently preferred embodiment thereof, as well as the best mode contemplated by the inventors of carrying out the invention. The invention, as described herein, is susceptible to various modifications and adaptations, as would be understood by those having ordinary skill in the art to which the invention relates.