Patent Publication Number: US-2023138318-A1

Title: Moldboard with a scraping tool for a milling machine

Description:
TECHNICAL FIELD 
     The present disclosure relates to milling machines, e.g. a cold planer, asphalt milling machine, and the like. Specifically, the present disclosure relates to a moldboard and associated attachments disposed behind the rotary cutting drum assembly of such machines. 
     BACKGROUND 
     Rotary tools such as cutting drums are routinely employed by milling machines such as cold planers, asphalt milling machines, and the like for ripping up a work surface such as soil, loose rock, asphalt, pavement, concrete, etc. During this process, a rough surface such as shown in  FIG.  1    with grooves is often created. This rough surface may be problematic for several reasons. 
     For example, the rough surface may still be used as an interim road surface so that entire roads are not shutdown during construction. The rough surface may adversely affect traction or create undesirable vibration for vehicles that pass over the rough surface. 
     German Patent No. DE202008016953U1 discloses a construction machine, in particular a stabilizer or a recycler, which has a rotor housing in which a milling or mixing rotor is arranged. These machines are known for the stabilization or consolidation of soils, with which binders, or example lime or cement, can be mixed into the soil to improve its ability to be installed and as well as its load-bearing capacity. To adapt the rotor housing to different working depths of the milling and mixing rotor, the rear housing part in the direction of travel has a flap which attached to the rotor housing so that it can pivot about a horizontal axis. In order to deposit the homogeneously milled material evenly behind the stabilizer or recycler, a wiper lip is attached to the adjustable flap, which extends between the side walls of the rotor housing over the entire working width of the machine. 
     As can be seen, a device for removing the rough surface created by a milling machine or the like is still needed. 
     SUMMARY 
     A milling assembly for use by a milling machine is provided. Such a milling assembly according to an embodiment of the present disclosure may comprise a pair of side panels, a rear moldboard terminating at a bottom edge, and a scraper that is attached to the bottom edge of the moldboard. 
     A scraper for use with a moldboard of a milling machine according to an embodiment of the present disclosure may comprise a rigid material including at least one of the following: a hardened steel having a hardness of at least 50 Rockwell Scale C, a carbide, and PCD diamonds. 
     A scraper for use with a moldboard of a milling machine according to another embodiment of the present disclosure may comprise a rigid scraping portion manufactured from a rigid material including at least one of the following: a hardened steel having a hardness of at least 50 Rockwell Scale C, a carbide, and PCD diamonds. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
       The accompanying drawings, which are incorporated in and constitute a part of this specification, illustrate several embodiments of the disclosure and together with the description, serve to explain the principles of the disclosure. In the drawings: 
         FIG.  1    illustrates a rough cut asphalt surface that may be created by a milling machine if a device such as a scraper configured according to an embodiment of the present disclosure is not used. 
         FIG.  2    is a perspective view of a machine such as an asphalt milling machine or the like that includes a milling assembly with a moldboard at its rear. This machine employs a scraper attached to the moldboard according to an embodiment of the present disclosure. 
         FIG.  3    is an enlarged detail view of the scraper attached to the moldboard of  FIG.  2    at the rear of milling assembly. 
         FIG.  4    is rear perspective view of the milling assembly, and moldboard employed on the milling machine of  FIG.  2    removed from the machine. This views shows a scraper configured according to an embodiment of the present disclosure attached to the moldboard. 
         FIG.  5    is a side view of the milling machine of  FIG.  2    depicting the scraper disposed behind the milling drum assembly. 
         FIG.  6    is an enlarged detail view of the scraper and milling drum of  FIG.  5   . 
         FIG.  7    is a rear view of another embodiment of scraper that employs a plurality of bits that are attached to the moldboard using a mounting plate. 
         FIG.  8    shows a similar embodiment to that of  FIG.  7    except that a mounting block is employed instead of a mounting plate. 
     
    
    
     DETAILED DESCRIPTION 
     Reference will now be made in detail to embodiments of the disclosure, examples of which are illustrated in the accompanying drawings. Wherever possible, the same reference numbers will be used throughout the drawings to refer to the same or like parts. In some cases, a reference number will be indicated in this specification and the drawings will show the reference number followed by a letter for example,  100   a ,  100   b  or by a prime for example,  100 ′,  100 ″ etc. It is to be understood that the use of letters or primes immediately after a reference number indicates that these features are similarly shaped and have similar function as is often the case when geometry is mirrored about a plane of symmetry. For ease of explanation in this specification, letters and primes will often not be included herein but may be shown in the drawings to indicate duplications of features, having similar or identical function or geometry, discussed within this written specification. 
     The present disclosure relates to the moldboard of a milling asphalt machine. Currently, moldboards do not fully remove the material from breakout areas left behind the milling asphalt due to bolt-on carbide scrapers. More particularly, the present disclosure pertains to a moldboard attachment in a milling asphalt machine for interacting with the surface. The machine includes attachments such as plate(s) or milling bits that act as scrapers. These scrapers may have patterns designed to interact with the breakout areas and can be attached to the moldboard. 
       FIG.  2    illustrates a perspective view of an exemplary milling machine  10 , according to the present disclosure. Machine  10  includes a frame  12  and a milling assembly  14  positioned on the underside of frame  12 . Milling assembly  14  may be integrally formed with frame  12  or may be otherwise coupled to milling assembly  14 . Machine  10  also includes a conveyor assembly  16  configured to advance the milled material from milling assembly  14  away from the ground surface, for example, to be deposited into a bed of a truck. Machine  10  includes a plurality of wheels or track members  18  coupled to frame  12  via a plurality of hydraulic cylinders  20 . Machine  10  also includes a moldboard  22  positioned to the rear of milling assembly  14  via a moldboard support structure  24 . 
     It is noted that milling assembly  14  may include side doors  26  on each side portion of milling assembly  14 . Moldboard  22  and side doors  26  enclose an interior rotor or milling drum assembly  90  (e.g., see  FIG.  5   ) that engages and mills the ground surface. Each side door  26  may be movably coupled to frame  12  via at least one side hydraulic cylinder  28 , for example, in order to raise the side door  26  to inspect or repair milling assembly  14  and/or the internal drum assembly. 
     Referring to  FIGS.  2    thru  5 , the moldboard  22  may help milling assembly  14  to remove the ground surface by removing any loose aggregate or debris that has not been captured by the milling drum assembly. Moldboard  22  may help to push the loose aggregate back toward the milling drum assembly, which may then urge the aggregate to conveyor assembly  16 . Removing the loose aggregate may help yield a clean and smooth milled surface behind machine  10 , which may then be more easily resurfaced. In order to further urge any loose aggregate toward the milling drum assembly, moldboard  22  may also include an angled interior surface and/or nozzles to dispense fluid. As discussed in greater detail below, moldboard support structure  24  connecting moldboard  22  to machine  10  may help increase the range and degrees of freedom of motion of moldboard  22  to accurately traverse the ground surface, without introducing bending or other strains on moldboard support structure  24 . 
     Also a scraper  100  (shown in  FIGS.  2    thru  6 ),  200  (shown in  FIGS.  7  and  8   ) may be attached to the moldboard in order to smooth out a surface such as asphalt, etc. 
     With continued reference to  FIGS.  2    thru  4 , the moldboard  22  is mounted to a rear portion of machine  10  via moldboard support structure  24 . Moldboard support structure  24  includes a rear hydraulic cylinder  30 . Rear hydraulic cylinder  30  includes a piston rod  32  movable within and extending out of a piston barrel  34 . The movement and position of piston rod  32  relative to piston barrel  34  depends on the movement and pressure of hydraulic fluid, as is known to one having skill in the art. 
     Focusing on  FIG.  4   , the moldboard support structure  24  also includes a trunnion mount  52 , and trunnion mount  52  may be coupled to piston barrel  34  in order to couple rear hydraulic cylinder  30  to milling assembly  14  or to frame  12 . Trunnion mount  52  may allow rear hydraulic cylinder  30  to pivot in one or more directions. In one aspect, the connection of rear hydraulic cylinder  30  to machine  10  may include at least one U-joint trunnion mount, for example, a dual trunnion mount including two U-joint trunnion mounts. Moldboard support structure  24  may also include a bearing  36  coupling moldboard  22  to piston rod  32 . For example, rear hydraulic cylinder  30  may be connected to a bottom portion of moldboard  22  via bearing  36 . In one aspect, bearing  36  may include a spherical portion (not shown), allowing rear hydraulic cylinder  30  to pivot in at least one direction relative to the bottom portion of moldboard  22 . 
       FIGS.  5  and  6    show a rotary drum assembly (may also be referred to as a milling drum assembly  90 ) that may be provided inside of the milling assembly  14 . A plurality of bits  92  are shown that break-up surfaces such as asphalt, concrete, etc. Other configurations for the milling assembly  14  are possible in other embodiments of the present disclosure. 
     As alluded to earlier herein,  FIG.  1    shows the ruts or roughened surface of asphalt that are produced by the milling process, and that may be removed or minimized using scrapers configured according to various embodiments of the present disclosure. 
       FIG.  4    shows moldboard support structure  24  connecting moldboard  22  to machine  10 . It is noted that portions of machine  10  are removed in  FIG.  4    in order to more clearly illustrate these connections and other pertinent aspects of this disclosure. Rear hydraulic cylinder  30  includes at least two fluid ports  38  coupled to at least two hydraulic fluid lines  40  in order to selectively raise or lower piston rod  32 , and accordingly raise or lower moldboard  22 . 
     It may be necessary to raise or lower moldboard  22  in order to ensure that moldboard  22  follows the ground surface during milling and urges any loose aggregate back toward milling assembly  14  and the milling drum assembly for removal. Also, enough force may be needed to force the scraper downward to remove the striations in the asphalt, etc. Moldboard  22  may include a handle (not shown) to allow a user to grip and/or manipulate moldboard  22 , for example, during inspection or repairs. It is also noted that  FIG.  4    illustrates side door  26  being movably coupled to frame  12  via two side hydraulic cylinders  28  positioned, for example, at a front portion and a rear portion of side door  26 . 
     As discussed above, rear hydraulic cylinder  30  may be coupled to moldboard  22  via bearing  36 , and bearing  36  may be a cylindrical rod. Bearing  36  may allow relative movement between moldboard  22  and rear hydraulic cylinder  30 , and may reduce the likelihood of wear on both components. Bearing  36  may couple a bottom portion  44  of moldboard  22  to a piston coupling  46  at a bottom of piston rod  32 . Bottom portion  44  of moldboard  22  may include one or more projections  48 . Piston coupling  46  and one or more projections  48  may be circular. Piston coupling  46  may be positioned adjacent to one projection  48  or between two projections  48 . Bearing  36  may then pass through piston coupling  46  and the one or more projections  48 . The coupling may provide for a gap on one or both sides of piston coupling  46  of rear hydraulic cylinder  30 . 
     As noted above, rear hydraulic cylinder  30  may be coupled to machine  10  via a trunnion mount  52 . Rear hydraulic cylinder  30  may be “mid-mounted” to machine  10 , meaning that rear hydraulic cylinder  30  is coupled to a middle or central portion along the height of machine  10 , or two such cylinders may be provided on either lateral side as shown in  FIG.  4   . Piston barrel  34  may be mounted on or positioned substantially even with a top portion of milling assembly  14 , and below a user operation position. Trunnion mount  52  may be bolted to a top portion of milling assembly  14  or directly to frame  12 . Trunnion mount  52  may be a dual-trunnion mount or double U-joint trunnion mount. 
     Turning to  FIG.  3   , the scraper  100  (scraper  200  is not shown in  FIG.  4    but it is to be understood that it may be substituted for scraper  100 ) may be fastened to the bottom edge  54  of the moldboard  22  via mounting blocks  56  shown in  FIG.  6   . Other methods of attachment may be used in other embodiments of the present disclosure. In  FIG.  6   , the scraper  100  is shown to include a rectangular side profile  102  including a bottom surface  104  that is substantially parallel to the pattern left by the cut (e.g., within 30.0 degrees). This may not be the case in other embodiments of the present disclosure. As shown in  FIG.  7   , the scraper  200  may include a series of projections  202  that are laterally spaced apart from each other. One or more scrapers  100 ,  200  may be positioned to the rear of the milling drum assembly  90 , etc. 
     Next, one or more embodiments of a scraper that may be provided as a replacement part or a retrofit in the field will now be discussed. 
     Starting with  FIGS.  4  and  5   , such a scraper  100  for use with a moldboard of a milling machine may be made from a rigid material including at least one of the following: a hardened steel having a hardness of at least 50 Rockwell Scale C, a carbide, and PCD (polycrystalline diamond) diamonds. This rigid material may include any combination of these materials, such as an alloy, etc. 
     As best seen in  FIG.  6   , the scraper  100  may include a pointed front attack edge  106 . The pointed front attack edge  106  may be formed by a front surface  108 , and a bottom surface  104  that form an acute included angle  110  that ranges from 60.0 degrees to 90.0 degrees in some embodiments of the present disclosure. Other angles for the included angle may range from 0 to 180.0 degrees. In other embodiments, this pointed front attack edge may be formed by a conical surface  201   a  or the point  201  of a cutting bit  92  (e.g., see  FIG.  7   ), etc. 
     Still referring to  FIG.  6   , a rear attachment surface  112  may connect the front surface  108  to the bottom surface  104 , either directly or indirectly. Also, the pointed front attack edge  106  may be formed by a pair of surfaces (e.g., see  104 ,  108 ) comprising the rigid material. 
     Focusing now on  FIG.  6   , a scraper for use with a moldboard of a milling machine may have a rid scraping portion manufactured from a rigid material (e.g., described above herein) that defines a width  114  (measured along the lateral direction that may be parallel to the axis of rotation of the cutting drum) to the thickness  116  (measured perpendicularly to the lateral direction) ratio. 
     As best seen in  FIG.  7   , the mount portion  206  may include a series of projections  202  that are spaced apart from each other a predetermined distance  208 . More specifically, each of the series of projections may include a pointed attack edge  210 . For example, the pointed attack edge may be formed by a conical surface  201   a . This surface may define an included cone angle  216  that may range from 100.0 degrees to 160.0 degrees in some embodiments. 
     In some embodiments, the cutting bits  92  of the rotary cutting drum assembly may be interposed between the plurality of scrapers  200 . Put another way, the scrapers  200  are spaced longitudinally (e.g., see  208 ) along axis  94  (may be the same as the axis or rotation of the cutting drum assembly, or nearly so). Thus, in various embodiments, the series of projections may form a pattern configured to remove the striations left during a milling process. 
     The arrangement, function, and dimensions of the various features of any embodiment of a scraper, milling assembly, machine, milling drum assembly, bits, etc. as discussed herein may be altered as needed or desired to be different than what has been specifically mentioned herein. 
     INDUSTRIAL APPLICABILITY 
     In practice, a scraper, a milling assembly, a moldboard, and a machine using any of these components assemblies according to any embodiment described herein may be sold, bought, manufactured or otherwise obtained in an OEM (original equipment manufacturer) or after-market context. 
     It will be apparent to those skilled in the art that various modifications and variations can be made to the embodiments of the apparatus and methods of assembly as discussed herein without departing from the scope or spirit of the invention(s). Other embodiments of this disclosure will be apparent to those skilled in the art from consideration of the specification and practice of the various embodiments disclosed herein. For example, some of the equipment may be constructed and function differently than what has been described herein and certain steps of any method may be omitted, performed in an order that is different than what has been specifically mentioned or in some cases performed simultaneously or in sub-steps. Furthermore, variations or modifications to certain aspects or features of various embodiments may be made to create further embodiments and features and aspects of various embodiments may be added to or substituted for other features or aspects of other embodiments in order to provide still further embodiments. 
     Accordingly, it is intended that the specification and examples be considered as exemplary only, with a true scope and spirit of the invention(s) being indicated by the following claims and their equivalents.