Abstract:
A compact mobile variable angle vibrating screen with an overhead feed conveyor drive system configured to accommodate nesting into the feedbox of the vibrating screen by use of a 90-degree input shaft speed reducer; a V-belt drive and a drive shaft coupling the two and a motor mounted in front of and perpendicular to the head pulley of the feed conveyor, all arranged in a configuration to nest within a feed box of the vibrating screen and to minimize the need for offset feeding with the conveyor.

Description:
CROSS REFERENCE TO RELATED APPLICATIONS 
       [0001]    This application claims the benefit of the filing date of the provisional patent application having Ser. No. 61/522,016 filed Aug. 10, 2011. This application also relates to the co-pending patent applications, filed on even date herewith: 
         [0002]    bearing attorney docket number 11800.017U SCREEN LIFT MECHANISM FOR VARIABLE SLOPE VIBRATING SCREENS by Payton Schirm and Greg Young and 
         [0003]    bearing attorney docket number 11800.018U, entitled PLATFORM AND LADDER INTERFACE FOR VARIABLE SLOPE VIBRATING SCREENS by Payton Schirm and 
         [0004]    bearing attorney docket number 11800.020U, entitled CONVEYOR SUPPORT MECHANISM FOR VARIABLE SLOPE VIBRATING SCREENS by Rex Carter and 
         [0005]    bearing attorney docket number 11800.021U, entitled FINES SCALPING CHUTE FOR VARIABLE SLOPE VIBRATING SCREENS by Ken Irwin and Chris Reed and 
         [0006]    Bearing attorney docket number 11800.024, entitled MOBILE MODULAR SCREEN PLANT WITH HORIZONTAL AND VARIABLE OPERATING ANGLES, by Greg Young and Payton Schirm. 
         [0007]    The contents of these applications are incorporated herein in their entirety by these references. 
     
    
     BACKGROUND OF THE INVENTION 
       [0008]    This invention relates to vibrating screens and more particularly to compact variably sloped vibrating screens. 
         [0009]    Sometimes a screen is designed to be oriented in various sloped positions. This is frequently found in portable equipment that requires a lower profile for travel, as well as multiple sloped positions as needed for various screening applications. 
         [0010]    In the past, screens have provided for the ability to meet transport restrictions by generally scaling down the size and capacity of the screen. Others have used conveyors with all of the drive components mounted on one side of the conveyor. Still others have required that the drive guards be removed or other partial dismantling occurs to allow for proper nesting. While these systems have provided for variable positions and ability to nest conveyors into screen feed boxes, they did have several drawbacks, most significantly, a reduction in performance and output capacity and in one sided design an increased need for offset feeding which has known shortcomings. In the case of requiring dismantling to occur, there is additional time required to configure the mobile screen for transport; there is the risk that drive guards will not be removed and the system may be damaged, and that the drive guards may not be replaced, which often increases the risk of personal injury. 
         [0011]    Consequently, there is a need for improvement in conveyor systems for compact mobile variable slope vibrating screens. 
       SUMMARY OF THE INVENTION 
       [0012]    More specifically, an object of the invention is to reduce a need for offset feeding of the conveyor in the hopper and thereby more evenly distribute the feed across the width of the screen. 
         [0013]    It is a feature of the present invention to provide for drive components on a side of the conveyor and the front of the conveyor. 
         [0014]    It is an advantage of the present invention to reduce the width of the conveyor and drive component combination. 
         [0015]    It is another advantage of the present invention to better balance the weight distribution between sides of the conveyor and minimize twisting in the conveyor frame. 
         [0016]    It is another feature of the present invention to include a V-belt drive together with a drive shaft and a 90-degree speed reducer. 
         [0017]    It is another advantage of the present invention to allow the motor to be located safely away from the discharge material leaving the conveyor. 
         [0018]    The present invention includes the above-described features and achieves the aforementioned objects. 
         [0019]    Accordingly, the present invention comprises a vibrating screen with a nesting overhead feed conveyor which provides minimized offset feeding and the ability to nest within the feed box. 
     
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         [0020]    The invention may be more fully understood by reading the following description of the preferred embodiments of the invention, in conjunction with the appended drawings wherein: 
           [0021]      FIG. 1  is an elevation view of a material processing system of the present invention with a screen in an inclined operational configuration. 
           [0022]      FIG. 2  is an elevation view of the system of  FIG. 1  except that the screen is in a horizontal operational configuration. 
           [0023]      FIG. 3  is a close-up view of a portion of the system of  FIGS. 1 and 2  except that the screen is in an intermediate inclined operational configuration. 
           [0024]      FIG. 4  is a close-up elevation view of an intermediate conveyor support portion of the system and configuration shown in  FIG. 2 . 
           [0025]      FIG. 5  is an elevation view of the system of  FIG. 1  except that the screen is in a horizontal transport configuration. 
           [0026]      FIG. 6  is a close-up elevation view of an intermediate conveyor support portion of the system and configuration shown in  FIG. 5 . 
           [0027]      FIG. 7  is a close-up elevation view of a front conveyor support portion of the system and configuration shown in  FIG. 2 . 
           [0028]      FIG. 8  is a close-up elevation view of a front conveyor support portion of the system and configuration shown in  FIG. 5 . 
           [0029]      FIG. 9  is a plan view of the top of portions of the system and configuration of  FIG. 5 . 
           [0030]      FIG. 10  is a close-up elevation view of a tail section slide/pivot support portion of the system and configuration shown in  FIG. 2 . 
           [0031]      FIG. 11  is a close-up elevation view of a tail section slide/pivot support portion of the system and configuration shown in  FIG. 5 . 
           [0032]      FIG. 12  is a close-up, partially dismantled view of the conveyor  15  of  FIG. 9 . 
           [0033]      FIG. 13  is a close-up view of portions of the screen of  FIG. 1 . 
           [0034]      FIG. 14  is a schematic diagram of a hydraulic circuit of the present invention. 
           [0035]      FIG. 15  is a close-up view of a portion of the screen of  FIG. 13 . 
           [0036]      FIG. 16  is a very close-up partially exploded view of a portion of the assembly of  FIG. 15 . 
           [0037]      FIG. 17  is an end view of the screen of  FIG. 1 . 
           [0038]      FIG. 18  is a close-up view of portions of the screen of  FIG. 1 . 
           [0039]      FIG. 19  is a close-up partially dismantled view exposing portions of the gates of the screen of  FIG. 1 . 
           [0040]      FIG. 20  is a close-up view of a portion of the chutes of the screen of  FIG. 1 . 
           [0041]      FIG. 21  is a side view of the screen of the present invention. 
           [0042]      FIG. 22  is a side view of the screen of  FIG. 21 , but in sloped screen configuration. 
           [0043]      FIG. 23  is a view of the present invention in a detached modular configuration. 
       
    
    
     DETAILED DESCRIPTION 
       [0044]    Now referring to the drawings wherein like numerals refer to like matter throughout, and more specifically referring to  FIG. 1 , there is shown an elevation view of a material processing system of the present invention, generally designated  100 , with a screen  1  in an inclined operational configuration. System  100  includes a feed hopper  5  which may have grizzly bars or other sorting structure thereon to remove oversized objects. Screen  1  is shown disposed on feed hopper frame  236 , which is shown supported by feed hopper wheels  238 . The material which exits feed hopper  5  is fed up on belt feeder  6  and the bottom feed support section  7  portion of the overhead conveyor  101 . A single continuous belt can be supported by bottom feed support section  7 , independent intermediate conveyor support section  14  and overhead conveyor head support section  15 . Throughout this description, conveyors are discussed as being troughing belt-type conveyors; however, it should be understood that this is an exemplary design, and other systems for conveying material, such as chain conveyors, rollers, augers and any type of system suitable for transporting material could be used. Screen base frame  2  is shown supporting screen  1  and also access walkway railing  12 , so that both pivot together when the screen is sloped at an angle for operation. Screen  1 , overhead conveyor  101 , and feed hopper  5  are all supported by wheeled chassis main frame  4  which also supports, in a “frame fixed” or stationary configuration, cross conveyors  8 , blend chute  9  and under screen conveyor  10 . A ladder or vertical foot tread structure  11  is coupled to wheeled chassis  4  and not directly to screen base frame  2 , which supports access walkway railing  12 . It can be seen that steps to railing gap  13  have a variable width dimension when the screen  1  is sloped for operation, by manipulation of hydraulic adjustable support legs  16 . 
         [0045]    Now referring to  FIG. 2 , there is shown the system  100  where the screen  1  is in a horizontal operational configuration. Note that the steps to railing gap  13  remain substantially the same width along vertical foot tread structure  11 . Independent intermediate conveyor support section  14  is shown at the same angle as in  FIG. 1 , but the angle between independent intermediate conveyor support section  14  and overhead conveyor head support section  15  has changed. 
         [0046]    A more complete understanding of the function and operation of independent intermediate conveyor support section  14  can be gleaned by now referring to  FIG. 3 , which shows the overhead conveyor head support section  15  oriented at a 5 degree incline (between that of  FIGS. 1 and 2 .) 
         [0047]    Now referring to  FIG. 4 , there is shown a close-up elevation view of an intermediate conveyor support portion of the system and configuration shown in  FIG. 2 . The independent intermediate conveyor support section  14  remains at the same angle with respect to the wheeled chassis  4  in all positions of the screen base frame  2 . Linkage is shown which maintains this angle, yet allows for relative movement between bottom feed support section  7  and overhead conveyor head support section  15 . More specifically, there is shown an intermediate support main leg structure  140  which is pivotally coupled with chassis mounted support  148  and is coupled to intermediate support main linkage body  141  via main leg to main linkage body pivot pin  146 . Intermediate support main roller support structure  142  is fixed to intermediate support main linkage body  141  via main roller support to main linkage body connection point  145  and pivotally coupled to bottom feed support section  7  via bottom feed to intermediate support pivotal link  143 . Similarly, Intermediate support main roller support structure  142  is coupled to overhead conveyor head support section  15 . Pivoting main linkage body to chassis support  144  is pivotally coupled to both intermediate support main linkage body  141  and chassis mounted support  148 . 
         [0048]    Now referring to  FIG. 5 , there is shown an elevation view of the system of  FIG. 1 , except that the screen is in a horizontal transport configuration. 
         [0049]    Now referring to  FIG. 6 , there is shown a close-up elevation view of an intermediate conveyor support portion of the system and configuration shown in  FIG. 5 . In this configuration, the intermediate support main leg structure  140  is substantially horizontal, thereby meaning that the intermediate support main roller support structure  142  is at a lower elevation with respect to the chassis mounted support  148 . 
         [0050]    Now referring to  FIG. 7 , there is shown a close-up elevation view of a front conveyor support portion of the system and configuration shown in  FIG. 2 . Overhead conveyor head support section  15  is held in place by upper slide arm  71  and lower slide arm  72 , which are coupled via sliding connection point  73 . The length of upper slide arm  71  and lower slide arm  72  is controlled by hydraulic adjustable arm  74 , which is coupled at a lower end to lower slide arm  72 , which is coupled at pivot point  76  to screen base frame secured support structure  75 . Hydraulic adjustable arm  74  is coupled at an upper end to upper slide arm  71 , which is coupled to overhead conveyor head support section  15  at conveyor to slide arm pivot point  77 . In this horizontal operational configuration, overhead conveyor head support section  15  is directly above, but separated from screen  1 . 
         [0051]    Now referring to  FIG. 8 , there is shown a close-up elevation view of a front conveyor support portion of the system and configuration shown in  FIG. 5 . Overhead conveyor head support section  15  is clearly shown disposed, at least in part, within a top portion of screen  1 . 
         [0052]    Now referring to  FIG. 9 , there is shown a plan view of the top of portions of the system and configuration of  FIG. 5 . 
         [0053]    Now referring to  FIG. 10 , which shows a close-up elevation view of a tail section slide/pivot support portion of the system and configuration shown in  FIG. 2 , the bracket  200  is fixed to the wheeled chassis  4  while the fixed location  202  is fixed to the bottom feed support section  7  as it translates along its path. 
         [0054]      FIG. 11  is a close-up elevation view of a tail section slide/pivot support portion of the system and configuration shown in  FIG. 5 . Note that fixed location  202  is outside of the bracket  200 . 
         [0055]    Now referring to  FIG. 12 , there is shown a close-up view of a portion of the overhead conveyor  101 , which includes a head pulley  300  to cooperate with the conveyor belt (not shown) to move the conveyor belt and thereby transport material for processing. Head pulley  300  is driven through a speed reducer  310 , which may be a 90-degree speed reducing gear assembly which is coupled to a jack shaft  350 , which is coupled to v-belt drive  340  which is powered by motor  330 . Speed reducer  310  is preferably an input shaft-type speed reducer which is flange or face mounted to the conveyor frame and is shorter in width (along the turning axis of head pulley  300 ) than the motor  330 . The above system is supported at least in part by support structure  320 , which may be disposed at side mount pivot point  77 . Motor  330  may be a single speed motor, and speed of the rotation of the head pulley  300  can be changed by changing the size of sheaves on the motor  330  and jack shaft  350 . The length of the jack shaft  350  may be varied; i.e., replaced with a longer jack shaft if high speed operation is expected and, therefore, the trajectory of material of the head pulley  300  would be flatter and further. The width of the overhead conveyor  101  is reduced because the width of the head pulley  300  and speed reducer  310  combined is less than what it would have been had the motor been mounted next to the speed reducer  310  in the present invention, so its central axis is parallel to the turning axis of the conveyor head pulley. 
         [0056]    Now referring to  FIG. 13 , there is shown screen  1  raised to an inclined operation position by hydraulic adjustable support legs  16 , which comprise a cylinder  162  for providing lifting force and an outer adjustable support leg  163  and an inner adjustable support leg  164  which can be locked to a predetermined length by locking pin  165 . The screen is coupled to hydraulic adjustable support legs  16  at lifting point  161  and is pivoted about base frame pivoting point  160 . In operation, once the locking pin  165  is inserted, the cylinder  162  is commanded to pull down upon the locking pin  165 , thereby removing any slack in the system that can result in unwanted vibration of the support structure. Alternatively, a threaded rod, ball screw or other tensioning device could be used to remove slack. 
         [0057]    Now referring to  FIG. 14 , there is shown a hydraulic circuit, generally designated  1400 . Generally, the system controls the operation of hydraulic adjustable support legs  16  via cylinder  162  by controlling hydraulic pressure thereto. The system performs two main functions: 1) lifting and lowering the screen  1  to angled orientations and 2) reducing the slack or slope in the mechanism holding or applying a biasing force to urge the screen in such positions. Hydraulic pressure power unit  1420  includes a hydraulic pump  1410  and a tank  1422  for providing high pressure hydraulic fluid to the cylinder  162 . Hydraulic pump  1410  is coupled to system control valve  1430 , which may be a 3 position valve with a system control valve return to tank normal position  1432 , a system control valve return criss-cross flow position  1434  and a system control valve return up down position  1436 , depending on the direction the valve is slid. Two lines (A and B) exit system control valve  1430  and go to cylinder  162 . Note the cylinder  162  has a port for applying pressure to retract and another for extending. The lines into each of these ports are capable of providing fluid into and receiving fluid from the cylinder  162 . Lines A and B enter manifold  1440  and encounter manifold pilot operated check valve  1441 . Check valve  1441  allows free-flow of oil into cylinder  162 , but flow control valve  1444  meters oil out of cylinder  162 . 
         [0058]    When the screen  1  is operating and the system  1400  is attempting to minimize slack in the support system, Pilot open check valve  1441  holds pressure in the retract side of cylinder  162 . The accumulator  1450  stores the pressure in the system. Accumulator  1450  provides for this holding pressure to continue at a functional level longer and thereby reduce the frequency that the system will need to be re-pressurized to function optimally. A pressure gauge  1462  is provided so a worker can re-pressurize the accumulator when necessary. Alternately, this could be automated with a sensor and transducer loop etc. Flow fuses  1448  are included to minimize losses in the event of a sudden failure (e.g., a burst hose etc.). A dump valve  1460  is included for use during maintenance or other times when completely discharging the pressure in the system  1400  is desired. 
         [0059]    Now referring to  FIG. 15 , there is shown a close-up view of the hydraulic adjustable support legs  16  of the present invention, which includes cylinder  162  outer adjustable support leg  163 , inner adjustable support leg  164 , locking pin  165  and half circle void  168  in outer adjustable support leg  163  so as to receive locking pin  165 . A pin storage bracket  167  is shown disposed adjacent to the half circle void  168  and is used to hold locking pin  165  when not inserted through the holes. 
         [0060]    Now referring to  FIG. 16 , there is shown a closer partially exploded view of outer adjustable support leg  163 , inner adjustable support leg  164  and locking pin  165  combination of the present invention. 
         [0061]    Now referring to  FIG. 17 , there is shown an end view of the screen  1  with an innovative fines scalping feature of the present invention. The system functions as follows: fines drop below the bottom screen deck onto underscreen fines pan  402 , which carries the fines material to an area where they can be deflected into right-hand fines primary movable chute  150  and left-hand fines primary movable chute  170  or alternately passed down to underscreen discharge reject conveyor  406 . Right-hand fines primary movable chute  150  and left-hand fines primary movable chute  170  are connected to the screen and are tilted up and down as the screen  1  is moved between various angular operating, transport and/or maintenance positions. Right-hand fines primary movable chute  150  mates with right-hand fines secondary fixed chute  180 , which is fixed to the frame of the system (which does not pivot). Similarly, left-hand fines primary movable chute  170  mates with left-hand fines secondary fixed chute  190 . 
         [0062]    Now referring to  FIG. 18 , there is shown a side view of the screen  1  in a horizontal (non-angled) position. The chutes are visible. 
         [0063]    Now referring to  FIG. 19 , there is shown a partially dismantled screen of the present invention which exposes to view the underscreen fines pan  402 , adjustable deflecting gates  400  and underscreen discharge reject conveyor  406  and their respective orientations. 
         [0064]    Now referring to  FIG. 20 , there is shown a perspective view of the system of the present invention where nesting relationship of left-hand fines primary movable chute  170  and left-hand fines secondary fixed chute  190  is clearly shown. 
         [0065]    Now referring to  FIG. 21 , there is shown a side view of the screen  1  of the present invention in a horizontal configuration, the gap  13  between stationary access platform railing  212  and railing  12  is shown at a maximum. Note that the stationary access platform railing  212  is fixed to the wheeled chassis main frame  4  as is the ladder  11 . As the screen  1  pivots to various operating angles, the stationary access platform railing  212  and ladder  11  remain stationary; i.e., fixed to the frame  4 . When the screen is in a horizontal configuration, the stationary access platform railing  212  and the pivoting access platform  214  may be flush; i.e., no step up required. When the screen is pivoted upwardly as is shown in  FIG. 22 , the stationary access platform railing  212  is stationary, and the nearest portion of the pivoting access platform  214  has been relatively elevated, thereby requiring a person to step up from the stationary access platform  210  to the pivoting access platform  214 . However, as they walk along pivoting access platform  214 , the railing  12  is at a constant height. In another configuration, there may be a required step down when the screen is in a horizontal configuration; and at a midpoint between horizontal and maximum inclination, no step up or down would be required and when the screen is at a maximum inclination, there would be a required step up. This level at the middle angle of inclination approach minimizes the magnitude of the highest step up or down required over the range of inclination angles. This configuration is shown in  FIGS. 22 and 23 . 
         [0066]    Now referring to  FIG. 23 , there is shown an alternate configuration of the system of  FIGS. 1 and 2 , where the wheels  238  are attached to a feed hopper frame  236  which is detached from the wheeled chassis main frame  4 , which is now shown with wheels  230  attached thereto. This approach can permit use of the system without the feed hopper  5 , or it can permit separate towing of the feed hopper  5  from the remainder of the system. 
         [0067]    It is thought that the method and apparatus of the present invention will be understood from the foregoing description and that it will be apparent that various changes may be made in the form, construct steps, and arrangement of the parts and steps thereof, without departing from the spirit and scope of the invention or sacrificing all of their material advantages. The form herein described is merely a preferred exemplary embodiment thereof.