Abstract:
A lifter is disclosed which allows for an improved operating envelope of the faceplate. The lifter utilizes a motor having 210 degrees of rotation and lifting arms of a unique geometry to rotate a faceplate from a retracted position below and substantially behind the lifter baseplate to a dumping position above and substantially behind a lower hopper edge for the purpose of dumping refuse carts into a refuse collection vehicle. This dumps refuse further into the vehicle hopper, which minimizes the number of packing cycles required on a collection route. A faceplate is attached to the motor using two lifting arms. The faceplate has a fixed upper hook and may be configured with a sliding, retractable lower hooking mechanism or a spring loaded, cam actuated rotating hook mechanism. The faceplate may include multiple sets of attachment points for attaching the lifting arms to facilitate the mounting of the lifter on a refuse collection vehicle over a range of heights without necessitating replacement of the lifting arms.

Description:
RELATED APPLICATIONS  
       [0001]     This application is a continuation-in-part of U.S. patent application Ser. No. 10/803,281, entitled “Refuse Cart Lifter With An Improved Range Of Rotation” (Attorney Docket 14893US02), filed Mar. 18, 2004, which makes reference to, claims priority to, and claims the benefit of U.S. Provisional Patent Application Ser. No. 60/455,546, entitled “Refuse Collection Cart Lifter With An Improved Range Of Rotation” (Attorney Docket 14893US01), filed Mar. 18, 2003, the complete subject matter of which is hereby incorporated herein by reference in its entirety. 
     
    
     FEDERALLY SPONSORED RESEARCH OR DEVELOPMENT  
       [0002]     [Not Applicable] 
       [MICROFICHE/COPYRIGHT REFERENCE] 
       [0003]     [Not Applicable] 
       BACKGROUND OF THE INVENTION  
       [0004]     The present invention relates to refuse container lifting devices, and in particular to refuse cart lifting devices. Refuse containers are often quite heavy, and therefore refuse collection vehicles are generally equipped with refuse container lifting devices to assist the vehicle operator when emptying the refuse containers. However, a refuse collection vehicle may encounter several different types of refuse containers on a given collection route, and the differences in these refuse containers often require the use of separate lifting devices. For example, large commercial refuse containers, or dumpsters, are typically emptied by tipping the container over the edge of the vehicle hopper using a variety of lifting devices, including tipper bars and cable and winch arrangements.  
         [0005]     Refuse carts are relatively light refuse receptacles constructed from various plastics and other synthetic materials. Features of refuse carts may include for example hinged covers, locking covers, wheels, and handles in various locations and configurations. Capacities generally range for example from 30 gallons to 95 gallons. Refuse carts typically encountered in residential areas are emptied using a refuse cart lifter capable of engaging the refuse cart, lifting it, and inverting the refuse cart to empty refuse into the vehicle hopper.  
         [0006]     Many prior refuse cart lifters present a wide profile and thus protrude from the refuse collection vehicle so as to interfere with the emptying of commercial dumpsters when they are tipped over the edge of the vehicle hopper. Protruding cart lifters also created a hazard for the rear-loading refuse collection vehicle driver when backing up, and the side-loading refuse collection driver when navigating narrow roadways, such as alleys. Some lifter designs have addressed this problem by locating the lifter off to the side of or even completely beneath the refuse collection vehicle hopper. Others attempted to reduce the profile of the refuse cart lifter to address the lifter protrusion issue.  
         [0007]     Another problem in the refuse cart lifter industry is that cart lifters typically hang down from the refuse collection vehicle, and therefore reduce the vehicle&#39;s ground clearance, particularly on uneven ground. Thus, some lifter designs include a retracted position where the lifter faceplate is angled underneath the refuse collection vehicle hopper, rather than hanging straight down.  
         [0008]     Yet another issue involves refuse compaction cycles. Prior cart lifters continuously dump refuse into the portion of the vehicle hopper closest to the refuse cart lifter because these lifters cannot empty the refuse cart a substantial distance into the hopper when dumping. The refuse therefore quickly accumulates near the refuse cart lifter, which requires the vehicle operator to stop collecting carts and compact the refuse to prevent interference with the next lifter dumping cycle. Thus, a lifter that empties refuse carts further into the refuse collection vehicle hopper would decrease the amount of time and energy spent compacting refuse between refuse cart dumping.  
         [0009]     A further issue involves maintenance of the lifter. Elevated hydraulic loads associated with some lifters correspond to increased wear and strain on cart lifter systems. Also, some lifter motor designs are readily susceptible to damage from contaminants present in the hydraulic system and eventually require complex repairs or rebuilding that can typically only be performed at the manufacturer&#39;s facility. Many lifters also use bearings that require regular greasing.  
         [0010]     A separate issue involves the effect of varying dimensions associated with lifting points on the refuse carts with respect to lifter engagement. For example, the distance between lifting points on refuse carts is set to industry standards. In practice, however, the distance between lifting points can vary appreciably. If the distance is significantly less than the industry standard, substantial force may be applied to the lifting points by the lifter&#39;s engagement mechanism. Such force can damage the refuse cart lifting points and reduce the effective life of the lifter. On the other hand, if the distance is significantly greater than the industry standard, the lifter&#39;s engagement mechanism may fail to engage the refuse cart during dumping, resulting in dropped and damaged refuse carts. Thus, a lifter engagement mechanism that can adjust to the varying dimensions between refuse container lifting points would contribute to longer refuse cart and lifter life, while improving the lifter&#39;s refuse cart engagement while dumping refuse carts.  
         [0011]     Yet another problem with existing lifters is their limited ability to control the timing of the latch mechanism that engages the refuse container lifting points during dumping. For example, the timing of the operation of a typical sliding latch is dependent on the length of an actuating arm or member. Since the actuating arm or member is rigid and secured to fixed locations on the lifter, significant modifications must be made to the actuating arm or member attachment points if a longer actuating arm or member is used. Therefore, it would be advantageous to provide a means of controlling the timing of the actuation of the latch mechanism that is not dependent on the length of the actuating arm or member.  
         [0012]     A further related problem with many existing lifters is associated with the range of ground to sill height and tailgate angle conditions encountered by refuse collection vehicles on a routine basis. For instance, the phenomenon known as “suck back” refers to the situation where a lifter&#39;s latch system engages early in the upward dumping rotation of the lifter and therefore becomes fully extended before the end of a dumping cycle, which causes the latch to retract slightly during the last few degrees of upward dumping rotation. This situation can lead to dropping of the refuse containers into the hopper near the end of the dumping cycle. Conversely, the container may be located such that the lifter&#39;s latch system engages late in the upward dumping rotation of the lifter, which can cause difficulty in engaging the refuse container, or damage to the container when the lifter&#39;s latch system releases the container before the container reaches the ground. Thus, it would be advantageous to provide a means of controlling the timing of the actuation of the latch mechanism to compensate for varying pick up conditions.  
         [0013]     Another problem involves the mounting height of the lifter. Due to the standard height of the lifting points on refuse containers, the target height for the upper engagement member of a lifter during initial engagement of the refuse cart is approximately 34 inches. However, the angle of the faceplate relative to the refuse cart must also be considered. If the lifter faceplate is at an angle to the refuse cart of approximately eleven degrees or more when the lifter&#39;s upper engagement member reaches a height of approximately 34 inches during lifter operation, the lifter faceplate may cause the refuse cart to kick away from the lifter before the lower engagement member engages with the lower lifting point of the refuse cart. Given a fixed lifter arm length, the angle of the faceplate to the refuse cart during initial refuse cart engagement is dependent upon the height at which the lifter is mounted on the refuse collection vehicle. Hence, numerous lifter arm lengths are required to accommodate a range of lifter mounting heights while maintaining the required initial engagement faceplate angle. Providing numerous lifter arm lengths requires additional expense, time and effort to change out. A lifter capable of maintaining the required initial engagement faceplate angle over a range of mounting heights while requiring a minimum of lifter arm length changes is therefore desirable.  
         [0014]     Thus, a need exists in the refuse collection industry for a residential refuse cart lifter that: possesses a slim profile; provides improved ground clearance; decreases the amount of time and energy spent compacting refuse between the emptying of successive refuse carts; provides needed lifting capacity at lower hydraulic pressures; requires little maintenance; is easy to repair or rebuild at the end user&#39;s facility; provides a lifter engagement mechanism that can adjust to the varying dimensions between refuse container lifting points; provides a means of controlling the timing of the actuation of the latch mechanism; and is capable of maintaining an acceptable initial engagement faceplate angle over a range of mounting heights while requiring a minimum of lifter arm length changes to do so.  
       SUMMARY OF THE INVENTION  
       [0015]     The present refuse cart lifter has an improved operating envelope resulting from a wide range of rotation of the lifter faceplate in combination with a unique lifter arm design. This yields a refuse cart lifter that may be capable of being retracted when not in use for increased ground clearance, while also capable of dumping refuse further into the refuse collection vehicle hopper than prior lifters. This added dumping range increases the efficiency of refuse collection because a vehicle operator does not have to operate the vehicle&#39;s packing blade as frequently, resulting in savings in time and energy.  
         [0016]     The presently preferred version of the refuse cart lifter utilizes a slim profile motor to rotate a lifting arm and faceplate 210 degrees for the purpose of dumping refuse containers into a receptacle. It is preferable to use a dual rack and single pinion hydraulically actuated unit as the motor due to its thin profile and superior lifting capacity at lower hydraulic pressures. This motor design also is preferable due to its open gear design, which makes it less susceptible to damage from contaminants in the hydraulic fluid system, and for the ease with which the lifter can be repaired or rebuilt at the end users facility. This actuator may based on the design disclosed in U.S. Pat. No. 4,773,812, which is hereby incorporated by reference.  
         [0017]     The present refuse cart lifter may include a faceplate having multiple sets of lifting arm attachment points that allow the faceplate angle relative to the lifting arms to be changed without negatively affecting the operation of the lifter&#39;s latch mechanism. The use of alternate lifting arm attachment points reduces the number of lifting arm lengths required to maintain an acceptable initial engagement faceplate angle over a range of mounting heights.  
         [0018]     The faceplate is preferably attached to the motor using two lifting arms having a unique design that is capable of directing the faceplate substantially into the vehicle hopper when used with a motor having a wide range of rotation. This allows the lifter to be more compact in its home (retracted) position and improves ground clearance when mounted on the rear of a rear loading refuse collection vehicle. The faceplate may have one fixed saddle and one moveable latch mechanism. The latch mechanism may be based on the sliding latch design that is disclosed in U.S. Pat. No. 5,308,211 and related patents, which are hereby incorporated by reference, or a cam-driven, spring loaded latch as discussed below. The latter mechanism may accommodate varying dimensions between refuse container lifting points, and provides a means of controlling the timing of the actuation of the latch mechanism.  
         [0019]     The present lifter may also incorporate an adjustable faceplate having multiple sets of attachment points for the lifting arms. This feature may advantageously enable the lifter to be mounted to a refuse collection vehicle over a range of mounting heights while maintaining an operable saddle height and faceplate angle relative to the refuse cart without changing the length of the lifting arms by simply attaching the lifting arms to the faceplate at different sets of attachment points. This feature therefore may save time and money when mounting the same lifter on different vehicles with varying mounting heights.  
         [0020]     Other design features may include the use of composite bearing materials in exposed bearing areas, such as the bearings that form a part of the sliding latch guide, to make the unit more maintenance free by eliminating the need for regular greasing. Also, longer lifting and latch arms may be utilized to allow for mounting the lifter on the side of a side-loading refuse collection vehicle.  
         [0021]     The present lifter faceplate may extend partially underneath the refuse collection vehicle in the retracted position, and therefore may not protrude significantly outward of the refuse cart lifter motor. The slim profile of the lifter motor and the retracted position of the faceplate may function to preclude interference with the dumping of large commercial containers over the lifter. Thin bumpers may also be mounted to the vehicle to protect the lifter as large commercial containers are dumped into the hopper.  
         [0022]     To empty a residential refuse cart into the hopper of the refuse collection vehicle, the lifter commences an emptying cycle. During the emptying cycle, the lifter motor rotates the lifter faceplate from a retracted position partially beneath the vehicle such that a fixed saddle engages the refuse cart. As the lifter continues to rotate, the cart is lifted in a sweeping arc motion towards the hopper. Meanwhile, the latch mechanism engages a lower lifting point on the refuse cart to prevent the loss of the cart into the hopper as the cart is emptied. If using a sliding latch, a sliding latch guide can be incorporated to prevent unwanted movements of the sliding latch during operation, which includes bearings to reduce friction while sliding. At the end of the emptying cycle, the cart is positioned significantly inward of the outer hopper edge.  
         [0023]     An unloading cycle reverses the emptying cycle and the cart is brought back down to street level in a sweeping arc motion. As the cart descends, the sliding latch disengages the lower lifting point on the refuse cart, followed by the disengagement of the upper saddle and upper lifting point on the refuse cart after the cart reaches the ground. The lifter can then be rotated further until the faceplate returns to the retracted position, substantially under the refuse collection vehicle. 
     
    
     BRIEF DESCRIPTION OF SEVERAL VIEWS OF THE DRAWINGS  
       [0024]     A full and enabling disclosure of the present invention, including the best mode thereof, directed to one of ordinary skill in the art, is set forth in the specification, which makes reference to the appended figures, in which:  
         [0025]      FIG. 1  is a perspective view of an exemplary refuse cart lifter in accordance with the present invention incorporating a sliding latch mechanism shown in a retracted position;  
         [0026]      FIG. 2  is a perspective view of an exemplary refuse cart lifter in accordance with the present invention incorporating a sliding latch mechanism shown in an intermediate position;  
         [0027]      FIG. 3  is a perspective view of an exemplary refuse cart lifter in accordance with the present invention incorporating a sliding latch mechanism shown in a dumping position;  
         [0028]      FIG. 4  is a side view of an exemplary refuse cart lifter in accordance with the present invention incorporating a sliding latch mechanism shown in a retracted position;  
         [0029]      FIG. 5  is a side view of an exemplary refuse cart lifter in accordance with the present invention incorporating a sliding latch mechanism shown in an intermediate position;  
         [0030]      FIG. 6  is a side view of an exemplary refuse cart lifter in accordance with the present invention incorporating a sliding latch mechanism shown in a dumping position;  
         [0031]      FIG. 7  is a front view of an exemplary refuse cart lifter in accordance with the present invention incorporating a sliding latch mechanism shown in a retracted position;  
         [0032]      FIG. 8  is a front view of an exemplary refuse cart lifter in accordance with the present invention incorporating a sliding latch mechanism shown in a dumping position;  
         [0033]      FIG. 9  is a side view of an exemplary refuse cart adjacent to a refuse cart lifter in accordance with the present invention incorporating a sliding latch mechanism shown in a retracted position;  
         [0034]      FIG. 10  is a side view of an exemplary refuse cart lifter in accordance with the present invention incorporating a sliding latch mechanism shown engaging the upper lifting point of an adjacent refuse cart;  
         [0035]      FIG. 11  is a side view of an exemplary refuse cart lifter in accordance with the present invention incorporating a sliding latch mechanism shown in a dumping position engaging the upper and lower lifting points of a refuse cart;  
         [0036]      FIG. 12  is a perspective view of an exemplary refuse cart adjacent to a refuse cart lifter in accordance with the present invention incorporating a sliding latch mechanism shown in a retracted position;  
         [0037]      FIG. 13  is a perspective view of an exemplary refuse cart lifter in accordance with the present invention incorporating a sliding latch mechanism shown engaging the upper lifting point of an adjacent refuse cart;  
         [0038]      FIG. 14  is a perspective view of an exemplary refuse cart lifter in accordance with the present invention incorporating a sliding latch mechanism shown in a dumping position engaging the upper and lower lifting points of a refuse cart;  
         [0039]      FIG. 15  depicts the rear of a rear-loading refuse collection vehicle showing two lifters in accordance with the present invention incorporating a sliding latch mechanism mounted to the rear of the refuse collection vehicle;  
         [0040]      FIG. 16  is a side view of an exemplary refuse cart lifter in accordance with the present invention incorporating a sliding latch mechanism shown in a retracted position and mounted on a rear-loading refuse collection vehicle;  
         [0041]      FIG. 17  is a partially cut away side view of an exemplary refuse cart lifter in accordance with the present invention incorporating a sliding latch mechanism shown in a dumping position and mounted on a rear-loading refuse collection vehicle;  
         [0042]      FIG. 18  is a perspective view of an exemplary refuse cart lifter in accordance with the present invention incorporating a spring loaded, cam actuated latch mechanism shown in a retracted position;  
         [0043]      FIG. 19  is a perspective view of an exemplary refuse cart lifter in accordance with the present invention incorporating a spring loaded, cam actuated latch mechanism shown in an intermediate position;  
         [0044]      FIG. 20  is a perspective view of an exemplary refuse cart lifter in accordance with the present invention incorporating a spring loaded, cam actuated latch mechanism shown in a dumping position;  
         [0045]      FIG. 21  is a side view of an exemplary refuse cart lifter in accordance with the present invention incorporating a spring loaded, cam actuated latch mechanism shown in a retracted position;  
         [0046]      FIG. 22  is a front view of an exemplary refuse cart lifter in accordance with the present invention incorporating a spring loaded, cam actuated latch mechanism shown in a retracted position;  
         [0047]      FIG. 23  is a top view of an exemplary refuse cart lifter in accordance with the present invention incorporating a spring loaded, cam actuated latch mechanism shown in a retracted position;  
         [0048]      FIG. 24  is a perspective view of an exemplary refuse cart lifter in accordance with the present invention incorporating a spring loaded, cam actuated latch mechanism and multiple sets of faceplate mounting holes, the lifter shown in a retracted position;  
         [0049]      FIG. 25   a  is a side view of an exemplary refuse cart lifter utilizing the outer set of faceplate mounting holes shown in a retracted position;  
         [0050]      FIG. 25   b  is a side view of an exemplary refuse cart lifter utilizing the outer set of faceplate mounting holes shown in an intermediate position;  
         [0051]      FIG. 25   c  is a side view of an exemplary refuse cart lifter utilizing the outer set of faceplate mounting holes shown in a dumping position;  
         [0052]      FIG. 26   a  is a side view of an exemplary refuse cart lifter utilizing the inner set of faceplate mounting holes shown in a retracted position;  
         [0053]      FIG. 26   b  is a side view of an exemplary refuse cart lifter utilizing the inner set of faceplate mounting holes shown in an intermediate position; and  
         [0054]      FIG. 26   c  is a side view of an exemplary refuse cart lifter utilizing the inner set of faceplate mounting holes shown in a dumping position. 
     
    
     DETAILED DESCRIPTION OF THE INVENTION  
       [0055]      FIG. 1  depicts a first preferred embodiment of the present refuse cart lifter  50  shown in a retracted position. The motor  60  is affixed to the front side  56  of the baseplate  52 . The motor  60  depicted is a dual rack, single pinion hydraulic actuator capable of 210 degrees of rotation. Those skilled in the art, however, will appreciate that other motors may be adopted for use with the present invention. The rear side  54  of baseplate  52  can be attached to a refuse collection vehicle or a large refuse collection container. Dual lifting arms  76  are attached at a first end  78  of the lifting arms  76  to the rotatable shaft  62  (see  FIG. 4 ) of motor  60 . The second end  80  of the lifting arms  76  are attached to the faceplate  64 . In this view, the inner surface  66  of faceplate  64  is clearly visible, as is the saddle  74 .  
         [0056]     The inner surface  84  of a portion of the sliding latch  82  is also seen. The sliding latch  82  is connected to the baseplate  52  with dual latch arms  88 . A first end  90  of the latch arms  88  is pivotally connected to the front side  56  of baseplate  52 . A second end  92  of the latch arms  88  is rigidly connected to the sliding latch  82 . A pair of sliding latch guides  94  which limit undesirable sliding latch  82  movement in relation to faceplate  64  is also depicted.  
         [0057]      FIG. 2  depicts the first preferred embodiment of present refuse cart  50  lifter shown in an intermediate position. In this figure, the motor  60  has rotated the lifting arms  76  and swung faceplate  64  to a position essentially parallel to baseplate  52 . Note that latch arms  88  have also swung upwards with the sliding latch  82 , which has yet to slide in relation to faceplate  64  due to the geometry of the lifting arms  76  in relation to the latch arms  88 . Also shown in this figure is the location of the upper end  70  and the lower end  72  of faceplate  64 .  
         [0058]      FIG. 3  depicts the first embodiment of the present refuse cart  50  lifter shown in a dumping position, which is the extreme opposite of the retracted position depicted in  FIG. 1 . In  FIG. 3 , the motor  60  has further rotated rotatable shaft  62  and attached lifting arms  76  preferably past a vertical position. The resulting angle of the first end  78  of lifting arms  76  away from the back side  54  of the baseplate  52  (see  FIG. 4 ) or towards the hopper if the present refuse cart lifter  50  is mounted on a refuse collection vehicle (see  FIG. 17 ), combined with the design of the lifting arms  76  that directs the second end  80  of lifting arms  76  even further away from the back side  54  of the baseplate  52  serves to swing faceplate  64  to a position above and substantially behind baseplate  52 . Lifting arm  76  design directs the second end  80  of lifting arms  76  away from the back side  54  of the baseplate  52  (see  FIG. 1 ) by offsetting the second end  80  of lifting arm  76  from lifting arm  76  using, for example, a curve or an angle in lifting arm  76 . This wide range of rotation of motor  60  and unique geometry of lifting arms  76  facilitates the dumping of refuse further into the refuse receptacle or refuse collection vehicle hopper than otherwise possible using existing lifters.  
         [0059]     Latch arms  88  have also swung upwards with the sliding latch  82 . The first ends  90  of latch arms  88  are pivotally attached to the front side  56  of baseplate  52 , while the second ends  92  of latch arms  88  (seen better in  FIG. 1 ) are fixedly attached to sliding latch  82 . Latch arms  88  are of a length and geometry calculated to cause the sliding latch  82  to slide away from saddle  74  of faceplate  64  and engage the refuse cart at some point after faceplate  64  moves from the intermediate position depicted in  FIG. 2  to the dumping position in  FIG. 3 . A sliding latch guide  94  (see  FIG. 1 ) prevents undesirable movements of the sliding latch  82 , and includes bearings to reduce the sliding friction resulting from the movement of sliding latch  82 . The point at which sliding latch  82  begins to slide away from saddle  74  of faceplate  64  can be adjusted by varying either the location of the pivotal connection of the latch arms  88  to the front side  56  of the baseplate  52 , or the length and geometry of the latch arms  88  themselves, or both.  
         [0060]      FIGS. 4 through 6  depict side views of the first embodiment of the present refuse cart lifter  50  shown in the retracted, intermediate and dumping positions, respectively.  FIG. 4  shows one end of rotatable shaft  62 . In addition, this figure shows that the lower end  72  of faceplate  64  may located below and substantially behind baseplate  52  when the lifter is in the retracted position. The unique geometry of the lifting arms  76  and the latch arms  88  can also be seen. Note the effect of the lift arm geometry as the lift arms  76  are rotated the full 210 degrees to the dumping position in  FIG. 6 . Also important is the slim profile depicted in the retracted configuration of  FIG. 4 , showing the faceplate  64 , lifting arms  76 , and latch arms  88  located substantially behind the outermost face  61  of motor  60 . This facilitates the emptying of large commercial refuse containers over the refuse cart lifter, thereby enhancing the versatility of the refuse collection vehicle.  
         [0061]      FIG. 5  depicts a side view of the first embodiment of the present refuse cart lifter  50  in an intermediate position. As in  FIG. 2 , the faceplate  64  is substantially parallel to baseplate  52 . At this point, the movement of the latch arms  88  has not yet caused sliding latch  82  to slide away from saddle  74  of faceplate  64 .  
         [0062]      FIG. 6  depicts a side view of the first embodiment of the present refuse cart lifter  50  in the dumping position. Here, it can be observed that the relative connection points and geometries of lifting arms  76  and latch arms  88  have caused sliding latch  82  to slide away from saddle  74  of faceplate  64  as the faceplate  64  moved from the intermediate position shown in  FIG. 5  to the dumping position in  FIG. 6 .  
         [0063]     As discussed in reference to  FIG. 3 , the unique geometry of the lifting arms  76  coupled with 210 degrees of lifting arm  76  rotation from the retracted position serve to position the upper end  70  of faceplate  64  above and substantially behind baseplate  52 . This facilitates the dumping of refuse further into the receiving refuse container than otherwise possible with conventional lifters.  
         [0064]      FIG. 7  depicts a front view of the first embodiment of the present refuse cart lifter  50  in the retracted position. This view shows the vertical relation of faceplate  64  to the baseplate  52 , with faceplate  64  positioned well beneath baseplate  52 .  
         [0065]      FIG. 8  depicts a front view of the first embodiment of the present refuse cart lifter  50  in the dumping position. This view shows the sliding latch  82  extended out from the lower end  72  of faceplate  64 , and faceplate  64  positioned above baseplate  52 .  
         [0066]      FIGS. 9 through 11  show a side view of the emptying of a refuse cart using the first embodiment of the present refuse cart lifter  50 . Initially, an operator would position a refuse cart  104  adjacent to refuse cart lifter  50 , as depicted in  FIG. 9  (showing a side view of the first embodiment of the present refuse cart lifter  50  in the retracted position). The upper lifting point  106  and lower lifting point  108  of refuse cart  104  are also illustrated.  
         [0067]     Once refuse cart  104  is positioned adjacent to refuse cart lifter  50 , refuse cart lifter  50  would be operated to rotate lifting arms  76  to swing faceplate  64  up such that saddle  74  engages refuse cart upper lifting point  106  as seen in  FIG. 10 .  FIG. 11  depicts the dumping position of lifter  50 , which is reached after the continued rotation of lifting arms  76  from the intermediate position in  FIG. 10  causes the upper end  70  of faceplate  64  to swing over and substantially behind baseplate  52 , thereby dumping refuse from the refuse cart  104  far behind baseplate  52 . In addition, while faceplate  64  is rotating from the intermediate position depicted in  FIG. 10  to the emptying position shown here in  FIG. 11 , the relative geometries of lifting arms  76  and latch arms  88  cause sliding latch  82  to slide out and away from saddle  74  of faceplate  64  and engage refuse cart lower lifting point  108 . This prevents refuse cart  104  from falling into the refuse collection area when saddle  74  is inverted as seen in  FIG. 11 .  
         [0068]      FIGS. 12 through 14  depict the same sequence of events as  FIGS. 9 through 11  during the emptying of refuse container  104 , but from a perspective view. Refuse cart lifter  50  is shown in a retracted position adjacent to refuse cart  104  in  FIG. 12 .  FIG. 13  depicts the refuse cart lifter  50  engaging refuse cart upper lifting point  106  (not visible in this view) after lifting arms  76  have swung faceplate  64  up and away from baseplate  52 . Finally,  FIG. 14  shows the refuse cart lifter  50  faceplate  64  swung to the dumping position with both saddle  74  and sliding latch  82  engaging refuse cart  104  at lifting points  106  and  108 , respectively (not visible in this view).  
         [0069]      FIG. 15  depicts dual lifters  50  mounted to a refuse collection vehicle  100 . The refuse hopper  101  is shown, as is lower hopper edge  102 . As discussed previously, when refuse cart lifters  50  are operated to empty a refuse cart  104  (see, e.g.,  FIG. 12 ), lifting arms  76  will cause faceplate  64  to swing over and substantially inward of lower hopper edge  102 . This can be seen by examining  FIGS. 16 and 17 , which depict a refuse cart lifter  50  mounted on a rear-loading refuse collection vehicle  100 .  
         [0070]      FIG. 16  depicts refuse cart lifter  50  shown in a retracted position and attached to a refuse collection vehicle  100 . This figure emphasizes the slim side profile of the lifter  50 , which facilitates the dumping of large commercial containers over the refuse cart lifter  50  when refuse cart lifter  50  is in the retracted position.  FIG. 17  depicts the refuse cart lifter  50  in a the dumping position, and offers a cutaway view (represented by jagged lines) of the refuse collection vehicle hopper showing the upper end  70  of faceplate  64  angled over the baseplate  52  and extending substantially inward of lower hopper edge  102 . An embodiment of the present invention could also be readily mounted to a side-loading refuse collection vehicle (not shown). It should be understood that the term “refuse collection vehicle” is intended to be understood broadly to include any type of vehicle for receiving refuse such as, for example, front, rear or side-loading vehicles, dumpsters, intermediate containers, and the like.  
         [0071]     A second embodiment of the present refuse cart lifter  150  is depicted in  FIGS. 18 through 23 .  FIG. 18  depicts refuse cart lifter  150  positioned in a retracted position. The motor  160  is affixed to the front side  156  of the baseplate  152 . The motor depicted is a dual rack, single pinion hydraulic actuator capable of 210 degrees of rotation. The rear side  154  of baseplate  152  can be attached to a refuse collection vehicle or a large refuse collection container. Dual lifting arms  176  are attached to the rotatable shaft  162  (see  FIG. 20 ) of motor  160  at a first end  178  of the lifting arms  176 . The second end  180  (see  FIG. 23 ) of lifting arms  176  are attached to faceplate  164 .  
         [0072]     As lifter  150  lifting arms  176  are rotated, attached faceplate  164  swings in a corresponding arc as lifter  150  is either extended (see  FIGS. 19 and 20 ) or retracted (see  FIG. 18 ), similar to the operation of the first embodiment relating to refuse cart lifter  50 . Unlike the first embodiment of the present lifter  50  that uses a sliding latch  82 , however, lifter  150  utilizes a spring loaded, cam actuated rotating latch  182 .  
         [0073]      FIGS. 18 through 23  illustrate that rotating latch  182  is attached to actuating rod  192  that is itself attached to rotatable actuating arm  187 . Rotatable actuating arm  187  in turn is connected to lifting arm  176  such that actuating arm  187  can rotate in a scissors-like fashion in conjunction with the movement of lifting arm  176  at attachment point  194 . One end of actuating arm  187  tracks cam  198  via cam follower  196  (best seen in  FIG. 20 ). The other end of actuating arm  187  is attached to rotating latch spring bar  186  (see  FIG. 18 ), which is turn linked to rotating latch actuating rods  192  having springs  184 . Spring tension provided by springs  184  serves to ensure that cam follower  196  stays in contact with cam  198  (see  FIG. 20 ). When actuating arm  187  rotates, springs  184  are free to move rotating latch actuating rods  192 , which in turn engages the rotating latches  182  by pivoting rotating latches  182  around latch rod  190 . A refuse container can thus be held between rotating latch  182  and saddle  174  (see  FIG. 19 ). However, when lifter  150  is in the dumping position shown in  FIG. 20 , the weight of a refuse cart may act against springs  184  and disengage the refuse container. To prevent such disengagement, a positive stop  183  (shown in  FIG. 19 ) is located on the outer surface  168  of faceplate  164  to alleviate such action against springs  184 .  
         [0074]     Once the refuse container has been emptied, actuating arm  187  tracks cam  198  as lifting arms  176  are rotated back to a fully or partially retracted position, and rotating latch spring bar  186  opposes springs  184  to move rotating latch actuating rods  192  towards springs  184 . Rotating latches  182  consequently rotate around latch rod  190  and gradually disengage the refuse container as lifter  150  moves into a fully or partially retracted position.  
         [0075]     A third embodiment of the present invention is depicted in  FIG. 24 . This embodiment is similar to the second embodiment of the invention in basic structure and operation, but unlike the other embodiments of the present invention, this embodiment employs an adjustable connection between faceplate  265  and lifting arms  276 . This adjustable connection may employ multiple sets of attachment points  300  and  302  on faceplate  265  for connecting lifting arms  276  to faceplate  265 . Thus, the assembled configuration of faceplate  265  with respect to lifting arms  276  is adjustable, which facilitates the mounting of refuse cart lifter  250  at a range of mounting heights without changing lifting arm lengths. While  FIG. 24  depicts lifter  250  faceplate  265  as having two sets of attachment points for lifting arms  276 , more attachment points are contemplated. In  FIG. 24 , faceplate  265  is depicted attached to lifting arms  276  at a first set of attachment points  300 . The second set of mounting points  302  for lifting arms  276  are not in use.  
         [0076]     It should be understood that while the third embodiment depicts attachment points  300  and  302  on faceplate  265 , the present invention is not so limited. For instance, attachment points  300  and  302  could be located on lifting arms  276 . Similarly, while the third embodiment depicts the use of nuts and bolts to attach faceplate  265  to lifting arms  276 , other means of attachment known to persons of skill in the art, such as clamps, pins, etc., may also be used.  
         [0077]     The detailed operation of lifter  250  is similar to the above description of operation relating to lifter  150  with the exception of adjustable faceplate  265 . For example,  FIG. 24  depicts lifter  250  having a spring loaded, cam actuated rotating latch  282  as described with respect to lifter  150  above. Parts of lifter  250  shared with lifter  150  are identified with similar reference numbers that correspond to the numerals used with respect to lifter  150 . Thus, lifter  250  has a baseplate  252  having a rear side  254  and a front side  256 . Motor  260  is attached to baseplate  252  and drives lifting arms  276 , which are in turn attached to faceplate  265 . Faceplate  265  has an attached saddle  274  that, in conjunction with rotating latch  282 , serves to engage and hold refuse cart during the emptying of the cart.  
         [0078]     Rotating latch  282  is attached to actuating rod  292  that is itself attached to rotatable actuating arm  287 . Rotatable actuating arm  287  in turn is connected to lifting arm  276  such that actuating arm  287  can rotate in a scissors-like fashion in conjunction with the movement of lifting arm  276  at attachment point  294 . One end of actuating arm  287  tracks cam  298  via a cam follower  296  (not seen in this view, but similar to the cam follower  196  of the second embodiment of lifter  150  shown in  FIG. 22 ). The other end of actuating arm  287  is attached to rotating latch spring bar  286 , which is turn linked to rotating latch actuating rods  292  having springs  284 . Spring tension provided by springs  284  serves to ensure that cam follower  296  stays in contact with cam  298  (not seen in this view). When actuating arm  287  rotates, springs  284  are free to move rotating latch actuating rods  292 , which in turn engages the rotating latch  282  by pivoting rotating latch  282  around latch rod  290 . A refuse container can thus be held between rotating latch  282  and saddle  274 .  
         [0079]      FIGS. 25   a  through  26   c  illustrate how adjusting faceplate  265  facilitates changing the mounting height of lifter  250  without necessitating the replacement of lifter arms  276  with arms of a different length to compensate for the mounting height difference. Turning to  FIG. 25   a , lifting arms  276  of a specific length are attached to adjustable faceplate  265  at a first set of mounting points  300 . In this configuration, lifter  250  is mounted at mounting height B from the substantially level pickup surface  299  and presents a retracted ground clearance height of A when lifter  250  is in the retracted position shown. By way of illustration for comparison with the parameters shown in  FIG. 26   a  for the same given set of lifter arms  276 , Height A in this example is approximately 17.125 inches when lifter  250  is mounted at a height B of approximately 36 inches.  
         [0080]     In  FIG. 25   b , adjustable faceplate  265  is extended to an intermediate position for engaging a refuse container wherein faceplate  265  is substantially perpendicular to a substantially level pickup surface  299 . In this intermediate position, faceplate  265  is substantially parallel to a refuse container sitting on the substantially level pickup surface  299 , and height C of saddle  274  is adequate for proper refuse container engagement and disengagement. In general, the preferred saddle height C is approximately 34 inches. Saddle height C in this example is also approximately 34 inches.  
         [0081]     Finally,  FIG. 25   c  shows lifter  250  in the extended dumping position with refuse cart  104 , wherein adjustable faceplate  265  is positioned at angle D with respect to the horizontal. By way of illustration for comparison with the parameters shown in FIG.  26   c  for the same given set of lifter arms  276 , angle D is approximately 45 degrees. Length E is the distance from the back side  254  of base plate  252  to the forward most portion of refuse cart  104 . In this example, length E is approximately 32.5 inches. Height F represents the distance between the lower most portion of refuse cart  104  and substantially level pickup surface  299 . In this example, height F is approximately 33.75 inches. Finally, height G is the distance between the uppermost portion of refuse container  104  and substantially level pickup surface  299 . In this particular example, height G is approximately 78.875 inches.  
         [0082]      FIGS. 26   a  through  26   c  correspond to  FIGS. 25   a  through  25   c , respectively.  FIGS. 26   a  through  26   c  use identical lifting arms  276  to lifting arms  276  used in  FIGS. 25   a  through  25   c . In  FIG. 26   a , adjustable faceplate  265  has been adjusted by attaching the same lifting arms  276  from  FIGS. 25   a  through  25   c  at attachment points  302  instead of attachment points  300 . Lifter  250  mounting height B has been raised to height B′, which, by way of specific example only, is approximately 37.5 inches. Height A then changes to height A′. In this example, A′ is approximately 17 inches.  
         [0083]     By moving the attachment points of lifting arms  276  to set of attachment points  302 , it is possible for lifter  250  to achieve a height C′ of saddle  274  that is substantially the same as height C of saddle  274  in the intermediate position despite increased mounting height B′. This adjustment does not adversely affect the operation of lifter  250  in any significant way.  
         [0084]     For instance, by way of comparison with  FIG. 25   c , using the same lifter arms  276  used in  FIG. 26   c  alters angle D from approximately 45 degrees to approximately 54 degrees. Length E increases from approximately 32.5 inches to 35 inches. Height F slightly decreases from approximately 33.75 inches to 33.25 inches. Finally, height G increases from approximately 78.875 inches in  FIG. 25   c  to 80.875 inches in  FIG. 26   c.    
         [0085]     The adjustable faceplate  265  of lifter  250  discussed above with respect to  FIGS. 25   a  through  26   c  can be mounted over a range of mounting heights. By way of example only, the specific embodiment of lifter  250  depicted in  FIGS. 25   a  through  26   c  using lifting arms  276  of a set length may be capable of operating over a range of mounting heights from a low mounting height B of at least approximately 36 inches to a high mounting height B′ of at least approximately 39.5 inches while maintaining saddle height C at a height adequate for proper refuse container engagement and disengagement. Changes to lifter arm  265  length and configuration will lead to other ranges of mounting heights. For example, substituting a second set of lifter arms  265  that are approximately 2 inches longer than lifting arms  265  in the example discussed in  FIGS. 25   a  through  26   c  will result in a lifter  250  that may be capable of operating over a range of mounting heights from a low mounting height B of at least approximately 37.875 inches to a high mounting height B′ of at least approximately 40.875 inches while maintaining saddle height C at a height adequate for proper refuse container engagement and disengagement. Even longer lifting arms  276  may result in an even higher operable range of lifter  250  mounting heights B. For example, the mounting height may range from a low mounting height B of at least approximately 40 inches to a high mounting height B′ of at least approximately 43 inches while maintaining saddle height C at a height adequate for proper refuse container engagement and disengagement. Those of skill in the art will appreciate, of course, that other lifter arm  265  configurations and attachment points will further alter the operable parameters of lifter  250 .  
         [0086]     The words used above are words of description rather than of limitation. Although preferred embodiments of the invention have been described using specific terms, devices, relative positions, and methods, such description is for illustrative purposes only. It should be understood that aspects of the various embodiments may be interchanged both in whole or in part. Therefore, the spirit and scope of the appended claims should not be limited to the description of the preferred versions contained therein.  
         [0087]     For example, the present refuse cart lifter could utilize a single lifting arm or a single latch arm, or various multiples of each or both. Furthermore, the lifter could be mounted to freestanding refuse containers, intermediate containers, rear-loading refuse collection vehicles, or side-loading refuse collection vehicles. Thus, it should be understood that changes and variations may be made by those of ordinary skill in the art without departing from the spirit or the scope of the present invention, which is set forth in the following claims.