Patent Publication Number: US-2004050985-A1

Title: Mobile impact crusher assembly

Description:
CROSS-REFERENCE TO RELATED APPLICATIONS  
     [0001] The present application is a Continuation-In-Part (CIP) of U.S. patent application Ser. No. 10/245,483 filed on Sep. 17, 2002, entitled “Mobile Impact Crusher Assembly” whose inventor is Robert R. Rossi, Jr. application Ser. No. 10/245,483 is incorporated by reference herein in its entirety for all purposes. 
    
    
     
       FEDERALLY SPONSORED RESEARCH OR DEVELOPMENT  
       [0002] N/A  
       BACKGROUND  
       [0003] One important use of impact crushers is in assisting in the cleaning up and the reduction of waste in our society. Impact crushers are capable of recycling used concrete, asphalt, brick, cinder block, demolition debris, glass, and any other substances that are hard and brittle. Impact crushers are also used for crushing rock and other natural substances. The recycling of these materials is an increasingly important aspect in the cleaning and preservation of our environment. Impact crushers may reduce objects from a larger to a smaller size in order to recycle and/or store waste material.  
       [0004] An impact crusher uses a diesel/hydraulic system in order to operate. It is often the case that other pieces of machinery that work in conjunction with the impact crusher to reduce material from a base size to the desired size also have their own diesel/hydraulic systems. For instance, an excavator may load material into the impact crusher, and a screening device may be present to reduce the size of the material that is ejected from the impact crusher. Further, a conveyor and/or feeder system is commonly employed to transport material to and from the impact crusher. In addition to the increased cost of running these separate systems, operation of such numerous diesel/hydraulic systems also negatively impacts the environment.  
       [0005] An impact crusher is a device that typically includes a frame that defines an enclosure wherein material that is to be crushed is dropped vertically into the frame. A rotor is rotationally mounted within the frame and turns about a horizontal axis. The rotor is often provided with one or more crushing bars that contact the material that is dropped into the frame. The crushing bars impact the material and forces the material against either a wall of the frame or against one or more impact plates that are positioned within the frame. The impact plates are positioned for receiving the thrown material and are provided with a dampening member in order to reduce shock to the frame. The material is crushed into smaller objects by being thrown against these impact plates and is moved into a different section of the frame. Here, the materials again may be contacted by a crushing bar of the rotor and thrown against one or more impact plates to further reduce the size of the crushed material. Eventually, the material is discharged from the frame and is deposited either into a pile or onto a conveyor system which transports the crushed objects to be further processed.  
       [0006] Some impact crushers are provided with an adjusting mechanism that may be used in order to adjust the distance between the impact plates and the rotor. Such an adjustment of this distance between the impact plates and the rotor typically occurs when the impact crusher assembly is turned off. By varying the distance between the rotor and the impact plates, an adjustment of the size of the crushed objects may be realized. Additionally, this adjustment may be done in order to maintain the desired output size of the crushed objects since the impact plates change size naturally due to wear through normal use.  
       [0007] Impact crushers may be designed in various formats to produce the crushed objects. For instance, some impact crushers are designed such that the distance between the crushing bars of the rotor and the impact plates is very small, resulting in a crushing of the material that is more akin to grinding than to shattering the object by being thrown against an impact plate.  
       [0008] An impact crusher is typically employed at construction sites. These construction sites can be, for instance, where buildings are being demolished or where roads are being built or repaired. Material from these construction sites may be placed into the impact crusher, crushed into a suitable size by the impact crusher and a further processing machine, and then reused at this particular construction site. This allows for a quick, inexpensive supply of needed materials along with the reduction of waste to the environment.  
       [0009] Impact crushers crush hard materials. In fact, impact crushers may crush materials that contain steel. It is sometimes the case that material that contains steel when crushed by an impact crusher separates from the steel upon being crushed. An example of some material that may be crushed by an impact crusher includes: rock, rubble, stone, boulders, concrete, asphalt, brick, block, glass, demolition debris, and the like.  
       [0010] In some impact crushers, the most efficient mode of operation of the impact crusher is to keep the crushing section full of material. Material may be fed into the crushing section of the impact crusher by, for instance, a conveyor and/or feeder.  
       [0011] Impact crushers are stationary devices that typically are positioned at single locations in a construction site. Other pieces of machinery must be used in order to provide material to the impact crusher to be crushed. Additional equipment must be employed in order to remove the material that is ejected from the impact crusher, and must be used to further process the material into a desired size. Additionally, further equipment may be required in order to transport the ejected material from the impact crusher into a desired location. All of the equipment and/or systems used to transport material to and from the impact crusher, in addition to further process the material, require a source of power. Also, these systems must be maintained and often operated by a user. Elimination of these systems would prove beneficial in that less energy, manpower, and/or power sources would be needed to complete the process.  
       SUMMARY  
       [0012] The present invention improves upon previous impact crushers by providing for a mobile impact crusher assembly that can be attached to a piece of construction equipment such as an excavator. Additionally, the present invention also improves upon previous impact crushers by providing for a single pass mobile impact crusher assembly that is powered by the vehicle onto which it is attached. Such a configuration reduces the number of diesel/hydraulic systems that must be employed in the crushing of materials, along with a reduction in the amount of equipment that must be employed in reducing material to a desired size. The current impact crusher may dig and load objects therein in one orientation and crush and then deposit the crushed material in another orientation. Additionally, other benefits may be realized as described herein.  
       [0013] Various features and advantages of the invention will be set forth in part in the following description, or may be obvious from the description, or may be learned from practice of the invention.  
       [0014] The present invention provides for a mobile impact crusher assembly that is used for crushing objects. The assembly includes a frame that defines an enclosure with an exterior surface and an interior space with an inlet opening to the interior space. An outlet opening is disposed generally opposite the inlet opening. The frame defines a holding section in the interior space adjacent to the inlet opening. The frame further defines a crushing section in the interior space that communicates with the holding section and the outlet opening. The frame has a connection member configured for pivotal attachment to a vehicle. The connection member desirably is carried by the exterior surface of the frame. The vehicle may be, for instance, an excavator. A rotor is rotationally mounted relative to the frame and is disposed in the interior space. A guard may be present and may be configured to be positioned to block the inlet opening of the frame and prevent some of the objects from exiting the frame through the inlet opening. In an alternative exemplary embodiment of the present invention, in addition to or instead of the guard as previously mentioned, a spray jet or jets are present and is attached to the frame. The spray jet may be used for suppressing dust brought about by the crushing of materials.  
       [0015] The present invention also provides for exemplary embodiments of the mobile impact crusher assembly as discussed above where the guard includes a hinge that is configured to allow the guard to pivot with respect to the vehicle. Additionally, the mobile impact crusher assembly may be provided with a guard that has a support frame that supports an elastomeric dampener, which can be configured with a plurality of curtains arranged in a crisscross pattern.  
       [0016] The present invention also provides for a mobile impact crusher assembly as discussed above where the guard has a pair of clevises, each clevis having a pivot pin configured to allow the guard to pivot with respect to the vehicle. Further, the mobile impact crusher assembly may be configured as discussed above where the guard also has at least one cable that is configured for attachment to the vehicle. The cable is used for supporting the guard at a desired position.  
       [0017] Also provided for in accordance with the present invention is an exemplary embodiment of the mobile impact crusher assembly as discussed above which further has a hydraulic cylinder that engages the guard and is used for positioning the guard.  
       [0018] The mobile impact crusher assembly of the present invention may also be provided with a dust suppression system. This system may include a water tank that is configured for attachment to the vehicle, and a spray jet or jets that are attached to the frame. A water line may place these two components into fluid communication with one another, and a water pump may be used to force water through the water line and out of the spray jet in order to reduce dust brought about by the crushing of material. 
     
    
    
     BRIEF DESCRIPTION OF THE DRAWINGS  
     [0019]FIG. 1 is a side elevation view of a mobile impact crusher assembly in accordance with the present invention. The mobile impact crusher assembly is shown attached to an arm of a vehicle (shown schematically) and is preparing to receive objects into a holding section.  
     [0020]FIG. 2 is a side elevation view of the mobile impact crusher assembly shown in FIG. 1. The view shows the objects being crushed by a rotor and impact plates of the mobile impact crusher assembly, and reduced objects being deposited therefrom.  
     [0021]FIG. 3A is a side elevation view of an exemplary embodiment of a mobile impact crusher assembly in accordance with the present invention. The view shows a driving mechanism being a first frictional engaging member engaging a second frictional engaging member that is driven by a motor.  
     [0022]FIG. 3B is a side elevation view of an exemplary embodiment of a mobile impact crusher assembly in accordance with the present invention. The view shows the driving mechanism being a V belt that is connected between two drive pulleys.  
     [0023]FIG. 3C is a side elevation view of an exemplary embodiment of a mobile impact crusher assembly in accordance with the present invention. The driving mechanism is shown as being a motor coupled directly to a shaft of the rotor.  
     [0024]FIG. 4A is a front elevation view of the exemplary embodiment of the mobile impact crusher assembly shown in FIG. 3A.  
     [0025]FIG. 4B is a side elevation view of the mobile impact crusher assembly taken along line  4 B of FIG. 4A. The view shows the first and second impact plates being adjustable in order to control the size of the reduced objects that are crushed in the mobile impact crusher assembly.  
     [0026]FIG. 5 is a side elevation view of an exemplary embodiment of the mobile impact crusher assembly being connected to an arm of an excavator. The excavator is attached to a screener that may further process reduced objects that are crushed by the mobile impact crusher assembly.  
     [0027]FIG. 6 is a side elevation view of an exemplary embodiment of the mobile impact crusher assembly in accordance with the present invention. The view shows the mobile impact crusher assembly being connected to an arm of an excavator and depositing reduced objects therefrom into a screener. The screener may further reduce the size of the crushed objects and deposit them into a corresponding stockpile.  
     [0028]FIG. 7 is a side elevation view of another exemplary embodiment of the mobile impact crusher assembly of the present invention. The view shows a first impact plate being positioned so as to separate a holding section from a crushing section.  
     [0029]FIG. 8 is a side elevation view of the mobile impact crusher assembly shown in FIG. 7. Here the first impact plate is positioned so that the holding section is no longer isolated from the crushing section.  
     [0030]FIG. 9 is a top plan view of the mobile impact crusher assembly shown in FIG. 7.  
     [0031]FIG. 10 is a front view of the mobile impact crusher assembly shown in FIG. 7.  
     [0032]FIG. 11 is a side elevation view of a mobile impact crusher assembly in accordance with the present invention. The mobile impact crusher assembly has a guard pivotally attached to an arm of the vehicle and held in position away from a frame of the mobile impact crusher assembly by a cable.  
     [0033]FIG. 12 is a side elevation view of the mobile impact crusher assembly shown in FIG. 11 This view shows objects being crushed by a rotor and impact plates of the mobile crusher assembly, and the guard positioned so as to prevent objects from exiting the inlet opening of the mobile impact crusher assembly.  
     [0034]FIG. 13 is a top plan view of the guard of the mobile impact crusher assembly in accordance with the present invention. The guard includes a support frame that carries an elastomeric dampener.  
     [0035]FIG. 14 is a side elevation view of an exemplary embodiment of a hinge of the mobile impact crusher assembly in accordance with the present invention.  
     [0036]FIG. 15 is a partial cross-sectional view taken along line  15 - 15  of FIG. 11.  
     [0037]FIG. 16 is a side elevation view of an exemplary embodiment of the mobile impact crusher assembly in accordance with the present invention. Here, the guard is positioned by a hydraulic cylinder that is attached to an arm of the vehicle.  
     [0038]FIG. 17 is a side elevation view of an exemplary embodiment of the mobile impact crusher assembly in accordance with the present invention. A dust suppression system is present and includes a spray jet or jets that are attached to the mobile impact crusher assembly, and a water tank and water pump configured on an excavator to which the mobile impact crusher assembly is attached.  
    
    
     DETAILED DESCRIPTION  
     [0039] Reference will now be made in detail to embodiments of the invention, one or more examples of which are illustrated in the drawings. Each example is provided by way of explanation of the invention, and is not meant as a limitation of the invention. For example, features illustrated or described as part of one embodiment can be used with another embodiment to yield still a third embodiment. It is intended that the present invention include these and other modifications and variations.  
     [0040] Referring now to the drawings, FIG. 1 shows a mobile impact crusher assembly  10  in accordance with an exemplary embodiment of the present invention. The mobile impact crusher assembly  10  includes a frame  26  that has a connection member  22  located thereon. The frame  26  defines an enclosure with an exterior surface  31  and an interior space  33 . An inlet opening  35  allows access into the interior space  33 . An outlet or discharge opening  54  is located opposite from the inlet opening  35 . The frame  26  defines a holding section  28  adjacent to the inlet opening  35 . Also defined by the frame  26  is a crushing section  30  that is in communication with the holding section  28  and the outlet opening  54 .  
     [0041] The connection member  22  is configured to be able to receive a member of a vehicle in order to allow for the mobile impact crusher assembly  10  to be selectively connected and selectively disconnected from the vehicle. For instance, a series of bolts may be provided in order to allow for attachment and disconnection of the mobile impact crusher assembly  10  to the vehicle. However, it could be the case that the connection member  22  provides for a permanent connection between the mobile impact crusher assembly  10  and the vehicle.  
     [0042] The mobile impact crusher assembly  10  may be configured to be connected to any type of machine used in the excavation industry. Examples include a hydraulic excavator, a loader, a shovel, and/or a crane. The mobile impact crusher assembly  10  may replace the vehicle&#39;s bucket and may also be powered by the vehicle onto which it is attached. The mobile impact crusher assembly  10  may be used as a bucket and transfer device, as well as being a crusher that exhibits a controlled form of crushing. In order words, it may be adjusted to regulate the output size of crushed material. This could be significant in that different States require different sized material specifications for base material as well as other products.  
     [0043] As shown in FIG. 1, the vehicle onto which the mobile impact crusher assembly  10  is attached is an excavator  12 . More particularly, the mobile impact crusher assembly  10  is connected to an excavator arm  14 . A pivot  24  is provided on a portion of the excavator arm  14 . A hydraulic cylinder  18  is also provided on the excavator arm  14 . Actuation of the hydraulic cylinder  18  results in a corresponding rotation of the mobile impact crusher assembly  10  about the pivot  24 . Such a pivoting arrangement is commonly known in the art. A hydraulic cylinder line  20  feeds hydraulic fluid to the hydraulic cylinder  18 . Although the exemplary embodiment shown in FIG. 1 makes use of hydraulics in order to move and rotate the mobile impact crusher assembly  10 , it is to be understood that other mechanisms are possible in accordance with the present invention. For instance, a gear train arrangement could be used in order to provide the required movement and/or rotation of the mobile impact crusher assembly  10 .  
     [0044] The mobile impact crusher assembly  10  includes a rotor  32  that is used to crush objects  42 . The mobile impact crusher assembly  10  is designed to process objects  42  that may be hard materials and/or recyclable type materials. For instance, the objects  42  may be concrete, asphalt, brick, cinder block, and/or demolition debris. Additionally, hard and brittle objects such as rock or glass may also be crushed. The rotor  32  is provided with at least one and desirably more than one crushing bar  34 , which are disposed about the outer circumference of the rotor  32 . The rotor  32  may hold the crushing bars  34  with the use of wedges, bolts, or through the unique shape of the crushing bar  34 . The crushing bars  34  may be replaced once they begin to exhibit wear throughout normal operation of the mobile impact crusher assembly  10 . Many variations of the rotor  32  are possible under the scope of the present invention. For instance, instead of having crushing bars  34 , the rotor  32  may be provided with a series of grinding teeth that are used to crush the objects  42 . Additionally, any number of crushing bars  34  may be employed on the rotor  32 . One such alternate arrangement of the rotor  32  is disclosed in U.S. Pat. No. 4,140,284 to Jöbkes and this patent is incorporated herein in its entirety for all purposes.  
     [0045] It will be appreciated that under the scope of the present invention, various ways of driving the rotors  32  can be employed. The rotor  32  is rotatably mounted onto a rotor shaft  46 , the rotor  32  rotating relative to the frame  26 . The rotor shaft  46  may be secured onto the frame  26  by two outboard pillow block bearings (not shown) which are carried on the outside of the frame  26 . Rotation of the rotor  32  may be obtained by a driving mechanism as will be later explained. The driving mechanism may be run by its own source of power which may be, for instance, a diesel/hydraulic system that is mounted on the frame  26 . Such a diesel/hydraulic system  110  is shown schematically on the frame  26  in FIGS. 5 and 6. Additionally, the driving mechanism can be run from the hydraulic system of the vehicle. As schematically shown in FIG. 1 for instance, a diesel/hydraulic system  114  may supply hydraulic fluid through a hydraulic line  16  that is run through the excavator arm  14  and into the driving mechanism to eventually turn the rotor  32 .  
     [0046] The mobile impact crusher assembly  10  also includes at least a first impact plate  36  and desirably a second impact plate  38 . Each impact plate  36 ,  38  is mounted on the interior of the frame  26 . The first and second impact plates  36  and  38  aid in preventing the frame  26  from being damaged by the objects  42  thrown from the rotor  32 . The mobile impact crusher assembly  10  functions by having the rotor  32  rotate so that the crushing bars  34  strike objects  42  and hurl the struck objects against the impact plates  36  and  38 . This action breaks up the objects  42  and reduces them to a smaller desired size. The first and second impact plates  36  and  38  are attached to the frame via spindles  48 . The plates  36  and  38  may also be pivotally or non-pivotally mounted onto the frame  26 . The plates  36  and  38  are mounted such that they have some yield when struck by the objects  42  thrown by the crushing bars  34 .  
     [0047] Various mechanisms may be employed in order to absorb the force of the thrown objects  42 . For instance, dampening springs may be used to absorb the forces imparted onto the plates  36  and  38 . Additionally, a fluid dampening mechanism such as a hydraulic cylinder may be employed in order to absorb this force. Such a dampening mechanism may be employed on a spindle  48 .  
     [0048] As shown in FIG. 4B for example, the plates  36  and  38  may each be provided with a hardened surface  90  in order to provide for a long life of the first and second impact plates  36  and  38 , and consequentially minimize the number of times the plates  36  and  38  need to be replaced. However, it is to be understood that in all mobile impact crusher assemblies  10 , the parts will always suffer some degree of wear and will need to be replaced. However, in lieu of simply replacing the first and second impact plates  36  and  38 , the distance between the first and second impact plates  36  and  38  and the rotor  32  may be adjusted. By moving the distance of the plates  36  and  38  relative to the rotor  32  and the crushing bar  34 , one may either vary the size of the crushed objects that are expelled from the mobile impact crusher assembly  10 , or may compensate for the wear that is imparted onto the harden surfaces  90 . Placing the plates  36  and  38  farther from the crushing bars  34  results in larger crushed objects and vice versa. The construction of impact plates are known in the art, for instance please see U.S. Pat. No. 4,140,284 by Jöbkes that shows an alternate configuration of the impact plates, spindles, and rotor.  
     [0049] The mobile impact crusher assembly  10  is manipulated by the excavator arm  14  such that it may dig into rock or other objects  42 . As shown in FIG. 4B for example, teeth  50  and  52  are provided on either end of the frame  26  in order to, among other things, aid in the initial digging and tearing of the objects  42 , or to help scrape them into a holding section  28  of the mobile impact crusher assembly  10 . Once the mobile impact crusher assembly  10  has been manipulated such that objects  42  are placed into the holding section  28 , the objects  42  may then be reduced by the mobile impact crusher assembly  10 . Referring now to FIG. 2, it can be seen that once the objects  42  are placed into the holding section  28 , the mobile impact crusher assembly  10  may be manipulated by the excavator arm  14  such that the mobile impact crusher assembly  10  is rotated approximately 90° relative to the position shown in FIG. 1. This tilting allows the objects  42  to fall from the holding section  28  into the crushing section  30 . The rotor  32  is rotated, and the crushing bars  34  impact the objects  42  such that they are hurled against the first and second impact plates  36  and  38 .  
     [0050] As shown in FIG. 2 for example, the crushing of the objects  42  takes place in a crushing section  30  of the mobile impact crusher assembly  10 . The objects  42  are reduced to a first size upon contact with the first impact plate  36 , and are reduced to a subsequent smaller size upon their impact against the second impact plate  38 . The reduced objects  44  fall through the mobile impact crusher assembly  10  due to a combination of gravity and/or the dynamic forces imparted upon the reduced objects  44  by the rotor  32  and the impact plates  36  and  38 . The reduced objects  44  are discharged from the mobile impact crusher assembly  10  through a discharge opening  54 . The reduced objects  44  then fall into either a stockpile or some other vehicle or area that is immediately below the mobile impact crusher assembly  10 . Although shown as being in a substantially vertical orientation, it is to be understood that the mobile impact crusher assembly  10  may function in orientations other than those disclosed in FIGS. 1 and 2.  
     [0051] The driving mechanism  40  is shown in more detail in FIG. 3A. This particular configuration of the driving mechanism  40  includes a first frictionally engaging member  58  and a second frictionally engaging member  60 . The frictionally engaging members  58  and  60  may be, for instance, a first rubber tire  58  and a second rubber tire  60 . The second rubber tire  60  is driven by a motor  56  that receives power via an input power line  62 . The motor  56  can be a hydraulic motor  56  that is mounted on the frame  26  and is powered by a hydraulic input line  62  from the vehicle. A hydraulic output line  64  runs from the hydraulic motor  56  through the frame, and back to the vehicle. The first rubber tire  58  is engaged by the second rubber tire  60  such that rotation of the second rubber tire  60  causes a corresponding rotation of the first rubber tire  58 . The first rubber tire  58  is fixed to rotate with the rotor shaft  46 . Therefore, rotation of the first rubber tire  58  causes a rotation of the rotor shaft  46  which subsequently causes rotation of the rotor  32  (as shown in FIGS. 1 and 2). Although shown as being hydraulically powered, it is to be understood that the first and second rubber tire  58  and  60  arrangement shown in FIG. 3A may be powered by other means. For instance, an electric motor  56  may be coupled to the second rubber tire  60  and may drive the second rubber tire  60  in much the same way as the hydraulic motor  56 . Additionally, it is to be understood that the hydraulic lines  62  and  64  from and to the vehicle do not need to be present in other exemplary embodiments of the present invention. For instance, the hydraulic motor  56  may be powered by its own diesel/hydraulic system  110  that is contained on the frame  26 , as shown in FIG. 5 or elsewhere in other exemplary embodiments.  
     [0052] When the first and second rubber tires  58  and  60  are inflated they will press against each other in order to transmit motion of one to the other. The frame  26  may be specially reinforced in the section surrounding the drive mechanism  40  in order to protect the drive mechanism  40  and the associated bearings. By changing the diameter of the tires  58  and  60  and/or other components of the drive mechanism  40  as used in other exemplary embodiments of the present invention, as well as the hydraulic pressure of the drive mechanism  40  and/or the RPM of the rotor  32 , various output sizes of the reduced objects  44  may be attained.  
     [0053]FIG. 3B shows an alternate exemplary embodiment of the driving mechanism  40 . Here, a hydraulic motor  56  is present on the frame  26  but instead of driving the second rubber tire  60 , the hydraulic motor  56  drives a drive pulley  66 . Another drive pulley  68  is also present and is in communication with the rotor shaft  46 . The drive pulleys  66  and  68  are in communication with one another through a V-belt  69 . Rotation of the drive pulley  66  brought about by rotation of the hydraulic motor  56  will cause a corresponding movement of the V-belt  69  around the drive pulley  66 . Such motion of the V-belt  69  causes a corresponding motion of the drive pulley  68  which is in contact with the rotor shaft  46  causing rotation of the rotor  32  (as seen in FIGS. 1 and 2). Again, the hydraulic motor  56  need not be present in the exemplary embodiment shown in FIG. 3B. For instance, in other exemplary embodiments of the present invention, an electric motor may be substituted for the hydraulic motor  56  shown in FIG. 3B. Additionally, if a hydraulic motor  56  were to be used, the hydraulics required to run the hydraulic motor  56  may be supplied by an independent hydraulic/diesel system  110  that is present on the frame  26 , and is not run from the vehicle into the frame  26  or elsewhere, as shown in FIG. 5.  
     [0054]FIG. 3C shows yet another exemplary alternative embodiment of the driving mechanism  40 . Here, the hydraulic motor  56  is directly mounted onto the rotor shaft  46 . Hydraulic lines  62  and  64  are again present and are run from the vehicle into the frame  26  and are used to power the hydraulic motor  56 . As previously mentioned, the hydraulic motor  56  may be substituted with an electric motor in other exemplary embodiments of the present invention. Further, the hydraulic source may be independently created and housed on the frame  26  or elsewhere as opposed to being supplied from the hydraulics of the vehicle. The direct mounting of the hydraulic motor  56  may be accomplished by various ways known in the art. For instance, the shaft emanating from the hydraulic motor  56  may be coupled onto the rotor shaft  46 . In the case of mounting the hydraulic motor  56  directly onto the rotor shaft  46 , the RPM of the rotor  32  may be regulated by a hydraulic control value (not shown).  
     [0055]FIG. 4A shows a front elevation view of the mobile impact crusher assembly  10  having the driving mechanism  40  displayed in FIG. 3A. As can be seen, the driving mechanism  40  is positioned on an end of the frame  26  and is adjacent to the holding section  28 . A counter weight (not shown) may be placed on an opposite end from the driving mechanism  40  as is known in the art. Although not shown, a screen may be placed in the opening leading to the holding section  28 . Such a screen may help ensure that objects other than those sought to be placed into the holding section  28  are prevented from entering the holding section  28 .  
     [0056]FIG. 4B is a side elevation view taken along line  4 B of FIG. 4A. Here, it can be seen that the first impact plate  36  is adjusted to an adjusted position  70 , which is schematically indicated by the chain-dashed line representation of the first impact plate  36 . Similarly, the second impact plate  38  is shown being moved to an adjusted position  72 . The adjusted positions  70  and  72  may be provided by rotation of the threaded spindles  48 . As noted above, the effect of these adjustments in position is to vary the output size of the reduced objects  44  (as shown in FIG. 2). Additionally, wear on the hardened surfaces  90  of the first and second impact plates  36  and  38  may require adjustment of the plates  36  and  38  into the adjusted positions  70  and  72  in order to provide for the correct size of the reduced objects  44  (as shown in FIG. 2).  
     [0057] As shown in FIG. 4B for example, a hydraulic cylinder  112  may be provided on the frame  26  and in engagement with the first impact plate  36 . The hydraulic cylinder  112  may be actuated in order to close off and isolate the holding section  28  from the crushing section  30 . As such, the rotor  32  may be run, and the hydraulic cylinder may then move the first impact plate  36  so that objects  42  are then hit by the crushing bars  34  of the rotor  32 .  
     [0058] An alternative exemplary embodiment of the mobile impact crusher assembly  10  is shown is FIG. 7. Here, the hydraulic cylinder  112  is shown being in an actuated position in which the cylinder  112  extends through an elongated slot (not visible in FIG. 7 view), and the first impact plate  36  is positioned so as to isolate the holding section  28  from the crushing section  30 . This is accomplished by having the hydraulic cylinder  112  being pivotally attached to first impact plate  36  through a pivotal attachment  200 . The first impact plate  36  is also pivotally attached to the frame  26  at a pivotal attachment  204 . Upon isolation of the holding section  28  from the crushing section  30 , the holding section  28  may be used as a bucket as is present on a conventional excavator.  
     [0059] As the hydraulic cylinder  112  extends, the first impact plate  36  is pivoted about the pivotal attachment  204 . The hydraulic cylinder  112  is partially housed within a frame extension  206  of the frame  26 . Hydraulic fluid is fed into and out of the hydraulic cylinder  112  through hydraulic lines  224  and  226 . The hydraulic cylinder  112  is pivotally attached to the frame extension  206  of the frame  26  through a pivotal attachment  202 . The pivotal attachment  202  allows the hydraulic cylinder  112  to pivot with respect to the frame  26  during actuation of the hydraulic cylinder  112 .  
     [0060] The second impact plate  38  is shown as being pivotally attached to the frame  26  through a pivotal attachment  208 . As such, upon being struck by thrown objects  42 , the second impact plate  38  will pivot about the pivotal attachment  208 . A further pivotal attachment  210  is present on the second impact plate  38  in order to allow a rod  216  to be connected to the second impact plate  38  and pivot with respect thereto. The rod  216  extends through a spring  218 , a frame extension  222 , and an opening (not visible in the FIG. 7 view) through the frame  26 . The spring  218  engages the frame extension  222  of the frame  26  on one end thereof, and engages a plate  220  on an opposite end.  
     [0061] A limiting member  212  being a first nut  212  is connected to the rod  216  and engages the plate  220 . Another limiting member  214  being a second nut  214  is threadably engaged upon the rod  216 , the spring  218  being positioned between the first nut  212  and the second nut  214 . It is to be understood that in other exemplary embodiments of the present invention, the first and second nuts  212  and  214  may be either threadably connected onto the rod  216  or permanently affixed to the rod  216 . Objects  42  that are thrown against the second impact plate  38  impact the hardened surface  90 . The force of this impact is transferred through the rod  216  and causes the plate  220  to compress the spring  218 . The spring  218  exerts a force in response to the impact, and tends to absorb the force of the impact. The first and second nuts  212 ,  214  may be adjusted in order to vary the distance of the second impact plate  38  from the frame  26 . This adjustment may therefore allow for the regulation of the size and amount of the crushed objects  44  that are discharged from the mobile impact crusher assembly  10 . In one exemplary embodiment of the present invention, hydraulic cylinders may be incorporated into both of the first and second impact plates  36 ,  38  in order to help prevent oversized crushed objects  44  from exiting the mobile impact crusher assembly  10 .  
     [0062] Although described as having a threaded engagement, the rod  216  and nuts  212 ,  214 , the spring  218 , and related components may be configured with a manual spring style release system that provides for faster adjustment of the second impact plate  38 .  
     [0063] The exemplary embodiment of the mobile impact crusher assembly  10  shown in FIG. 7 has the rotor  32  being provided with two crushing bars  34 . Each of the crushing bars  34  is affixed to the rotor  32  by way of a wedge  228 . The wedge  228  is designed so that the wedge  228  tightens as the centrifugal force due to the rotating rotor  32  increases. In other exemplary embodiments of the present invention, other ways of attaching the rotor  32  and the crushing bars  34  are contemplated. For instance, pins, bolts, or welding may be employed in other exemplary embodiments. Also, in other exemplary embodiments of the present invention the crushing bars  34  may have a curved cross-section instead of a rectangular cross-section. The crushing bars  34  can have a curved section in order to fit into a corresponding curved section in the rotor  32  to provide for attachment of the crushing bars  34  onto the rotor  32 .  
     [0064]FIG. 8 shows the mobile impact crusher assembly  10  of FIG. 7 where the hydraulic cylinder  112  has been retracted such that the first impact plate  36  is positioned within the interior space  33  so that the holding section  28  is not isolated from the crushing section  30 . During use, the mobile impact crusher assembly  10  may have the first impact plate  36  positioned as shown in FIG. 7 and may be manipulated such that objects  42  are placed within the holding section  28 . At this point, the mobile impact crusher assembly  10  may be rotated such that the holding section  28  is for the most part above the crushing section  30 . Rotation of the rotor  32  may be started, and once a desired rotational speed is obtained the first impact plate  36  may be swung into the open position as shown in FIG. 8. At this point, objects  42  fall into the crushing section  30  from the holding section  28  and are reduced into the crushed objects  44 . This type of an arrangement may be advantages in that the rotor  32  may be prevented from being jammed due to the fact that it is at a fully developed speed before any contact with the objects  42  occurs.  
     [0065]FIG. 9 is a top view of the mobile impact crusher assembly shown in FIGS. 7 and 8. Here, the motor  56  is a hydraulic motor that is attached to the frame  26 . A shaft  230  is coupled to the motor  56  and extends across the frame  26 . The shaft  230  is rotationally mounted onto the frame  26  by way of a pair of bearing assemblies  232 . The driving mechanism is essentially the same as the driving mechanism  40  as shown in FIG. 3B. Here, a V-belt  69  is employed in order to allow for rotational motion to be transferred from the drive pulley  66  to the drive pulley  68 . The drive pulley  66  is connected to the shaft  230  such that rotation of the shaft  230  causes a corresponding rotation of the drive pulley  66 . As can be seen, this rotation is then transferred to the drive pulley  68  which is connected to the rotor shaft  46 . Here, the rotor shaft  46  is supported by a pair of bearing assemblies  234 .  
     [0066]FIG. 10 shows a front view of the exemplary embodiment of the mobile impact crusher assembly  10  displayed in FIGS. 7 through 9. Here, a guard  236  is positioned proximate to the inlet opening  35  of the frame  26 . The guard  236  may be configured such that objects  42  are only able to enter the mobile impact crusher assembly  10  if they are of a desired size and weight. It is to be understood that in other exemplary embodiments of the present invention, the presence of the guard  236  is not necessary.  
     [0067] Although shown as employing the driving mechanism  40  of FIG. 3B, it is to be understood that in other exemplary embodiments of the present invention drive components other than the V-belt  69  and the drive pulleys  66  and  68  may be employed. Additionally, hydraulic power may be substituted for other forms of power in running the driving mechanism  40  in other exemplary embodiments. An advantage of using a hydraulic driving mechanism  40  is that the hydraulic configuration allows for the reversal of the rotation of the rotor  32 . Reversing the rotor  32  will assist in clearing the crushing section  30 , referring now to FIG. 7, if large and/or non-crushable objects  42  are present within the crushing section  30 .  
     [0068]FIG. 5 shows the mobile impact crusher assembly  10  being connected to a first excavator arm  14  of an excavator  12 . The excavator  12  includes a second excavator arm  76  that is attached to the first excavator arm  14 . The second excavator arm  76  also has a second hydraulic cylinder  74  being attached thereto and being powered by the diesel/hydraulic system  114  of the excavator  12 . Actuation of the second hydraulic cylinder  74  causes a corresponding rotation of the first excavator arm  14  about the second excavator arm  76 . As can be seen from this arrangement, it is possible for the excavator  12  to manipulate the mobile impact crusher assembly  10  such that objects  42  are able to be scooped into the frame  26  of the mobile impact crusher assembly  10 . The excavator  12  may be moved back and forth on excavator tracks  78 . Additionally, the excavator  12  may swivel about the excavator swivel base  79  such that the first excavator arm  14 , second excavator arm  76  and the mobile impact crusher assembly  10  are rotated in a direction normal to the side elevational view shown in FIG. 5.  
     [0069] The mobile impact crusher assembly  10  as opposed to simply reducing the size of objects  42 , may also act to separate objects. For instance, steel may be separated from the product in which it is encased during a pass through the mobile impact crusher assembly  10 . Objects  42  that may be crushed by the mobile impact crusher assembly  10  include rock, rubble, stone, boulders, concrete, asphalt, brick, block, glass, demolition debris and the like.  
     [0070] In one exemplary embodiment of the present invention as shown in FIGS. 5 and 6 for example, a screener  80  is attached to the excavator  12 . Such a screener  80  is commonly known in the art, and its purpose is to further reduce or separate material placed into the screener  80 . The screener  80  may be provided with screener tracks  82  or tires (not shown) in order to aid in movement of the screener  80 . The screener  80  may be run by its own power source, or may be driven via the diesel/hydraulic system  114  of the excavator  12 . The screener  80  has a screener input  84  into which objects are deposited. The screener  80  then screens the inputted objects such that only objects of a desired size and/or those exhibiting certain desirable properties are outputted onto the screener output  86 . These objects are then subsequentially transferred off of the screener  80  and deposited into a stockpile  88  of screened material. However, in other exemplary embodiments of the present invention, output from the screener output  86  is sent directly to another vehicle which then transports the screened objects to a remote location as opposed to simply depositing the output from the screener output  86  into the stockpile  88 .  
     [0071] Since the mobile impact crusher assembly  10  is replacing the bucket of the excavator  12 , the operator of the excavator  12  may use the mobile impact crusher assembly  10  to scoop objects  42  to be crushed in much the same way as the operator would when using the normal bucket.  
     [0072]FIG. 6 shows a side elevation view of an exemplary embodiment of the mobile impact crusher assembly  10  in accordance with the present invention. Here, the mobile impact crusher assembly  10  is again attached to an excavator  12  and is shown as being rotationally pivoted on the first excavator arm  14 . The mobile impact crusher assembly  10  is in a substantially vertical orientation such that objects  42  are being crushed by the mobile impact crusher assembly  10  and are being expelled into the screener input  84  of the screener  80 . At this point, the reduced objects  44  are further processed by the screener  80  such that they are reduced in size and/or sorted according to desired properties. The output from the screener output  86  is deposited into the stockpile  88  of screened material.  
     [0073] It is to be appreciated that the mobile impact crusher assembly  10  may be connected to vehicles other than the excavator  12  in other exemplary embodiments of the present invention as schematically shown in FIG. 1. For instance, the mobile impact crusher assembly  10  may be configured to be attached to a vehicle  13  such as a loader, a shovel, and/or a crane. As such, attachment to only the excavator  12  is not always necessary. It is to be understood that the connection member  22  may be configured such that the mobile impact crusher assembly  10  is engageable with two or more different types of vehicles.  
     [0074] One advantage of the present invention is that the mobile impact crusher assembly  10  is capable of being mounted onto a vehicle as opposed to simply being positioned on the ground. Such a configuration allows for the elimination of an independent power source needed to run the stand-alone impact crusher that is positioned on the ground. Additionally, several steps can be combined or eliminated when the mobile impact crusher assembly  10  is mounted onto an arm of a vehicle. For instance, it is not necessary to load the objects  42  into the stand-alone impact crusher and then retrieve the reduced objects  44  from the crusher.  
     [0075] An additional advantage of the mobile impact crusher assembly  10  as disclosed in the present application is that the mobile impact crusher assembly  10  may produce a desired saleable object by a single pass of the objects  42  through the holding section  28  and the crushing section  30 . A saleable object is defined as an object outputted from the mobile impact crusher assembly  10  that is of a desired size, and in which no other machinery is needed to place the object into the mobile impact crusher assembly  10  or remove the reduced object therefrom. It is the case that current impact crushers are used for the purpose of reducing the objects  42  into reduced objects  44  which are then required to be further processed in order to achieve objects of the desired size. In essence, current impact crushers are preparation crushers and are not capable of producing saleable objects of the desired size. However, at least one exemplary embodiment of the present invention allows for saleable objects to be realized upon departing the discharge opening  54  through a single pass of the objects  42  through the holding section  28  and the crushing section  30 . It is also to be understood that in other exemplary embodiments of the present invention, the mobile impact crusher assembly  10  can be used in a preparation stage in reducing the objects  42 . As shown in FIGS. 5 and 6 for example, the reduced objects  44  are further processed by the screener  80 .  
     [0076] Significant savings can be realized if a single diesel/hydraulic system  114  is used on the excavator  12  and also powers the mobile impact crusher assembly  10  as opposed to two separate diesel/hydraulic systems, one being for the excavator  12  and the other for a stand-alone impact crusher. Further savings can also be realized in the exemplary embodiment shown in FIGS. 5 and 6 if the single diesel/hydraulic system  114  is also used to power the screener  80 .  
     [0077] It is therefore the case, that the present invention may eliminate the need for an elaborate hopper/feeder/crusher/conveyor system. The mobile impact crusher assembly  10  may utilize the holding section  28  as a hopper and feeder. By lifting and tilting the mobile impact crusher assembly  10  at the same time, the reduced objects  44  simply discharge at a desired height from the mobile impact crusher assembly  10  to create a stockpile without the use of a conveyor. When mounted on the excavator  12 , the excavator  12  can swivel about the excavator swivel base  79  anywhere in a  3600  circumference to deposit reduced objects  44 . This allows for multiple piles of the reduced objects  44  to be stock piled without moving the excavator  12  via the excavator tracks  78 .  
     [0078] The screen  80  may be mounted on the screener tracks  82  or simply mounted on tires (not shown) while being towed. Additionally, the screener  80  may have its own source of power in order to provide its own mobility as opposed to being simply towed by the excavator  12 . As can be seen, the present invention encompasses exemplary embodiments where the screener  80  is an independent vehicle from the excavator  12  and has its own power source, and also encompasses exemplary embodiments where the screener  80  and the excavator  12  are essentially one vehicle, each sharing their own power source.  
     [0079] In one exemplary embodiment of the present invention, the screener  80  is towed by the excavator  12  and is powered by the same power source which runs the excavator  12 . The excavator  12  may use the mobile impact crusher assembly  10  to scoop a load of objects  42  to be crushed. Once material is within the frame  26  of the mobile impact crusher assembly  10 , the excavator  12  may be rotated 180° in order to position the mobile impact crusher assembly  10  directly over the screener input  84 . Reduced objects  44  are discharged from the mobile impact crusher assembly  10  into the screen  80  for sizing purposes. The entire system, that being the excavator  12  along with the screener  80  may move forward using the tracks on the excavator  12  while digging, scooping, loading, crushing, screening, and then stock piling the screened material into the stock pile  88 . As can be seen, the mobile impact crusher assembly  10  is attached to the excavator  12 , and the screener  80  and may be capable of performing all of the various necessary tasks while the entire assembly is moving in any direction.  
     [0080] Referring now to FIG. 11, another exemplary embodiment of the mobile impact crusher assembly  10  is shown. Here, a guard  302  is provided and is attached to the excavator arm  14  of the excavator  12  (FIG. 5). The guard  302  is positioned away from the inlet opening  35  of the frame  26  such that objects  42  may be scooped into the mobile impact crusher assembly  10  through the inlet opening  35 . In this regard, the guard  302  is pivotally attached to the excavator arm  14  by a hinge  306 . The guard  302  is further held in the position shown in FIG. 11 by a cable  310 . As can be seen in FIG. 11, when the excavator  12  is not crushing the objects  42 , the guard  302  may be held away from the frame  26  by the hinge  306  and the cable  310 .  
     [0081] Referring now to FIG. 12, the mobile impact crusher assembly  10  of FIG. 11 is shown in the crushing position. Here, the frame  26  is rotated into the crushing position such that the guard  302  blocks the inlet opening  35  (FIG. 11) of the frame  26 . The guard  302  prevents the objects  42  from exiting the mobile impact crusher assembly  10  through the inlet opening  35  (FIG. 11). Absent the positioning of guard  302  as shown in FIG. 12, objects  42  may be inadvertently thrown out of the mobile impact crusher assembly  10  through the inlet opening  35  (FIG. 11) due to the crushing procedure brought about by the rotor  32  impacting the objects  42  and causing them to be moved throughout the interior of the frame  26 . The guard  302  may also assist in the dampening of noise associated with the crushing of objects  42  by the mobile impact crusher assembly  10 . The guard  302  may therefore deflect objects  42  that are thrown upward while the mobile impact crusher assembly  10  is operating. Consequently, the guard  302  may protect the excavator  12  from being damaged. The guard  302  may be configured in order to block the entire inlet opening  35 , or may be configured in order to block only a portion of the inlet opening  35  in accordance with various exemplary embodiments. A portion of the side face of the guard  302  is cut away in FIG. 12 in order to show the objects  42  being blocked by the guard  302 .  
     [0082] As can be seen in FIG. 12, the frame  26  engages the guard  302  such that the guard  302  is slightly lifted off of a support member  304 . The support member  304  may be a welded structure attached to the excavator arm  14  of the excavator  12 . The support member  304  may be used to support the guard  302  when the guard  302  is not engaged by the frame  26 . Further, the support member  304  may be used as a stop in order to prevent the guard  302  from rotating or moving past a desired location.  
     [0083] The hinge  306  used to provide pivotal attachment of the guard  302  to the excavator arm  14  may be seen in more detail in FIGS. 13 and 14. Here, the hinge  306  is made from a pair of devises  316  that are each rigidly attached to the excavator arm  14 . In one exemplary embodiment, they may be welded onto the excavator arm  14 . Alternatively, the devises  316  can be attached to the arm  14  with mechanical fasteners such as bolts and nuts. The guard  302  includes a frame support  320  that extends into each of the devises  316  and is pivotally retained thereon by a pair of pivot pins  308 . Although shown as employing a pair of devises  316 , it is to be understood that in accordance with other exemplary embodiments of the present invention that more or fewer of the devises  316  may be used in order to effect pivotal attachment of the guard  302 .  
     [0084] The support frame  320  incorporated into the guard  302  may include a steel structure, for instance tubular steel, that includes a series of crisscrossing members  331  forming a shallow cage that is open at the bottom and at the front end, which is nearest the hinge  306 . Guard  302  also desirably includes an elastomeric dampener  318  that lines the interior of the cage  320 . A plurality of side frame pieces  333  (FIG. 11) may be employed in order to form a structure which provides strength to the support frame  320 , forms an enclosure preventing objects  28  from escaping the inlet opening  11 , and allows for attachment of the elastomeric dampener  318 . The objects  42  (FIG. 12) may be retained by a combination of the support frame  320  and the elastomeric dampener  318 . The elastomeric dampener  318  may be made of natural gum rubber or may have, for instance, a durometer valve of forty. However, other configurations of the guard  302  are possible in accordance with the present invention. For instance, the guard  302  may be a single piece which is in the shape of a plate or a plate having side walls, and may be made of either a single rigid material or a single flexible material. As such, various constructions of the guard  302  are possible in accordance with other exemplary embodiments of the present invention.  
     [0085] In one exemplary embodiment of the present invention, the support frame  320  may be made from tubular steel that is welded together to form a framework that outlines the elastomeric dampener  318 . The elastomeric dampener  318  may be rubber that is both pliable and durable, and may be either glued or bolted onto the support frame  320 . The elastomeric dampener  318  and possibly the support frame  320  may be somewhat flexible such that they momentarily take the shape of objects  42  (FIG. 12) that contact the guard  302 .  
     [0086]FIG. 15 is taken along line  15 - 15  of FIG. 11 and shows the guard  302 . Here, the elastomeric dampener  318  may be composed of multiple hanging curtains  319  that run lengthwise within cage  320 . Dampener  318  also can include a plurality of hanging cross-curtains  321  that are designed widthwise within cage  320  and intersect curtains  319  so that curtains  319  and cross-curtains  321  crisscross one another within the guard  302 . An advantage of this configuration is that the cross-curtains  321  can absorb a higher amount of force from propelled objects  42  due to lengthwise impacting on the cross-curtains  321 , and due to strength added from their crisscross configuration. As shown in FIG. 12 for example, dampener  318  includes a base  322  that rests against and closes off the top of cage  320 , and curtains  319  and cross-curtains  321  depend from base  322 . As shown in FIGS. 11 and 12, a front flap  317  of the dampener  318  hangs down in front of the front end of the guard  302 . As such, the guard  302  defines an open side nearest to the arm  14 . This open side is advantageous in that objects  42  are more easily retained by the guard  302  since the frame  26  may be more snuggly fit into the guard  302  since the open face allows for such insertion. However, the present invention is not limited to a specific configuration of the elastomeric dampener  318 , and various shapes may be employed in other exemplary embodiments.  
     [0087] As can be seen in FIG. 15, the guard  302  employs a cable  310 . Alternatively, a pair of cables  310  may be used in place of the single cable  310  that is run through an opening in a vehicle cable connection member  312 . Each of the cables  310  (or cable  310  if one is used) is pivotally attached to the excavator arm  14  by the vehicle cable connection member  312 , which in one exemplary embodiment may be welded onto the excavator arm  14 . As shown in FIG. 13, the cables  310  are pivotally attached to the guard  302  by a pair of guard cable connection members  314 . The guard cable connection members  314  may be spaced from one another in order to provide desired stability of the guard  302 . However, it is to be understood that in other exemplary embodiments of the present invention, that more or fewer than two guard cable connection members  314  may be used, along with variations of the positioning of the guard cable connection members  314 .  
     [0088] As shown in FIG. 11, the cable  310  is in tension, and supports one end of the guard  302 , when the guard  302  is disposed away from the inlet  35  of the frame  26 . Once the excavator arm  14  is rotated into the position shown in FIG. 12, tension is released on the cable  310  and it becomes slack, in which case the guard  302  may be allowed to be pivoted about the hinge  306 . As such, in accordance with one exemplary embodiment of the present invention, the guard  302  may be properly positioned without the use of any power source. However, other exemplary embodiments of the present invention exist in which the guard  302  is positioned by an electrical or hydraulic source. FIG. 16 shows one such exemplary embodiment where a hydraulic cylinder  324  is pivotally attached to the excavator arm  14  and the guard  302 . The hydraulic cylinder  324  may be powered by the diesel/hydraulic system  114  of the excavator  12 , and placed into communication with the diesel/hydraulic system  314  through a hydraulic line  322 . Actuation of the hydraulic cylinder  324  will cause the guard  302  to be pivoted about the hinge  306  and positioned at a desired location.  
     [0089] Although shown as being attached to the excavator arm  14 , it is to be understood that other configurations of the guard  302  are possible in accordance with the present invention. For instance, the guard  302  may be attached to the frame  26 . In this case, the guard  302  may be moved in order to block the inlet opening  35  of the frame  26  by gravity through the configuration of the guard  302 , or may be moved by an electric or hydraulic system such as the exemplary embodiment shown in FIG. 16.  
     [0090] The guard  302  may be detached from the excavator  12  by removing the guard  302  at the hinge  306  and at the vehicle cable connection member  312  in order to allow for transportation of the excavator  12 , or to mount another attachment onto the excavator arm  14 .  
     [0091] The present invention also provides for a mobile impact crusher assembly  10  that includes a dust suppression system as shown in FIG. 17. Here, the dust suppression system includes a water tank  352  that may be mounted on the excavator  12 . A water pump  356  may be included that may run off of a power system included with the excavator  12 , or may be provided with a small engine that operates the water pump  356 . Water may be pumped through a water line  354  located on the excavator arm  14  into a spray jet or jets  350  attached to the frame  26  near the outlet  54 . During crushing of the objects  42 , the dust suppression system may be activated such that water is sprayed out of the spray jet or jets  350  proximate to the discharge opening  54  (FIG. 12) of the frame  26  in order to cut down on the amount of dust produced by the crushing operation. The dust suppression system may be used apart from the guard  302  discussed above, or may be used in combination with the guard  302  as previously discussed.  
     [0092] It should be understood that the present invention includes various modifications that can be made to the embodiments of the mobile impact crusher assembly  10  described herein as come within the scope of the appended claims and their equivalents.