Patent Publication Number: US-2021172230-A1

Title: Counterbalance assembly and system

Description:
CROSS-REFERENCE TO RELATED APPLICATIONS 
     This Application is related to, and claims the benefit of priority of U.S. Provisional Application No. 62/660,053, filed on 19 Apr. 2018, entitled COUNTERBALANCE ASSEMBLY AND SYSTEM and U.S. Provisional Application No. 62/767,555, filed on 15 Nov. 2018, entitled COUNTERBALANCE ASSEMBLY AND SYSTEM, the contents of which are incorporated herein by reference in their entirety for all purposes. 
    
    
     BACKGROUND OF THE INVENTION 
     When managing the movement of two components with respect to one another, it is sometimes beneficial to employ a mechanism to counterbalance the components. This invention provides an assembly configured to counterbalance components movable relative to one another as well as a counterbalanced system including such components. 
     SUMMARY OF THE INVENTION 
     According to one aspect of the invention, an assembly is configured to counterbalance components movable relative to one another, the assembly including a mounting bracket configured to be coupled to one of the components; a follower arm pivotally coupled to a follower arm mounting point on the mounting bracket; a follower coupled to a follower mounting point on the follower arm; means for exerting force between a force exerting means mounting point on the mounting bracket and a force exerting means mounting point on the follower arm; and a cam configured to be coupled to another one of the components in such a way that the follower contacts a cam profile of the cam. 
     According to optional aspects of the assembly, the means for exerting force can be selected from the group consisting of a mechanical spring, a pneumatic spring, and a hydraulic spring. More than one of each of these springs may be used, or a combination of types of springs may also be used in the practice of this invention. Specifically, the means for exerting force can be one mechanical spring, or can be two more such springs. More specifically, a mechanical spring such as a compression spring or springs can be interposed between the mounting point on the mounting bracket and the mounting point on the follower arm. The assembly can also include a spring guide associated with and positioned to guide each spring. The cam profile can include a detent, and the follower can include a roller. 
     According to another aspect of the invention, a counterbalanced system includes components movable relative to one another and at least one assembly counterbalancing the components relative to one another. The at least one assembly has a mounting bracket coupled to one of the components, a follower arm pivotally coupled to a follower arm mounting point on the mounting bracket, a follower coupled to a follower mounting point on the follower arm, means for exerting force between a force exerting means mounting point on the mounting bracket and a force exerting means mounting point on the follower arm, and a cam coupled to another one of the components in such a way that the follower contacts a cam profile of the cam. The at least one assembly facilitates movement of the components relative to one another. 
     According to optional aspects of the counterbalanced system, one of the components can be a vehicle panel. Also, the vehicle panel can include a vehicle hood. Additionally, one of the components can be oriented at an angle with respect to a horizontal plane in a first position and movable relative to the other one of the components to be oriented at a smaller angle with respect to the horizontal plane in a second position. The component oriented at the angle with respect to the horizontal plane in the first position can be oriented substantially vertically. Also, the components can be pivotally coupled relative to one another in addition to being coupled by the at least one assembly. 
     According to other optional aspects of the counterbalance system, non-limiting examples of one of the components include: a copier lid; a printer lid; medical equipment; diagnostic equipment; a cover for industrial machinery; a food preparation machine such that machinery can be moved out of the way when not in use; a fold-up or fold-down work surface; a flip-up counter such as those in restaurants, bars and other venues; a cover for an armored vehicle hatch such as a hatch on a tank; bitable displays for gaming machines or gaming systems or other video systems; and any other application in which one component is coupled for movement with respect to another component in a controlled manner with perceived weight management. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         FIG. 1  is side view of an exemplary embodiment of the invention in a first configuration; 
         FIG. 2  is a perspective view of the exemplary embodiment of the invention shown in  FIG. 1 ; 
         FIG. 3  is another perspective view of the exemplary embodiment of the invention shown in  FIG. 1 ; 
         FIG. 4  is a rear view of the exemplary embodiment of the invention shown in  FIG. 1 ; 
         FIG. 5  is a side view of the exemplary embodiment of the invention shown in  FIG. 1 , in another configuration; 
         FIG. 6  is another perspective view of the exemplary embodiment of he invention shown in  FIG. 1 ; 
         FIG. 7  is a side view showing the movement of the exemplary embodiment of the invention shown in  FIG. 1 ; 
         FIG. 8  is a perspective view of a second exemplary embodiment of the invention; 
         FIG. 9  is another perspective view of the second exemplary embodiment of the invention; 
         FIG. 10  is a side view of a third exemplary embodiment of the invention; 
         FIG. 11  is a perspective view of the third exemplary embodiment of the invention; 
         FIG. 12  is a perspective view of a fourth exemplary embodiment of he invention; 
         FIG. 13  is a side view of the fourth exemplary embodiment of the is invention; 
         FIG. 14  is a cross-sectional view of the fourth embodiment of the invention in a closed position; 
         FIG. 15  is a cross-sectional view fourth embodiment of the invention in a partially open position; 
         FIG. 16  is a cross-sectional view of the fourth embodiment of the invention in an open position; 
         FIG. 17  is a partially exploded perspective view of embodiment of the invention; 
         FIG. 18  is an exploded view of the fifth embodiment of the invention; 
         FIG. 19  is a perspective view of a sixth embodiment of the invention in a closed position; and 
         FIG. 20  is a perspective view of the sixth embodiment of the invention in an open position. 
     
    
    
     DETAILED DESCRIPTION OF THE INVENTION 
     Although the invention is illustrated and described herein with reference to specific embodiments, the invention is not intended to be limited to the details shown. Rather, various modifications may be made in the details within the scope and range of equivalents of the claims and without departing from the invention. 
     It is to be understood that if the same reference numbers are applied to different embodiments, that the part number to which the reference number refers is the same or similar for the each embodiment, i.e., part number  112  refers to a spring in each of the six exemplary embodiments described below. 
     Generally, a counterbalance mechanism is provided by this invention, including embodiments utilizing a compression spring or springs (or other compressive force device such as a pneumatic cylinder, an air spring or other means for exerting force) acting on a follower arm in combination with a customizable cam profile generating a counter acting force to the center of gravity of a system (e.g., a truck hood, a door, etc.). In one aspect of the invention, a vertically mounted mechanism is provided to counterbalance and/or provide a customizable opening profile to a system having multiple components. This is achieved by utilizing a compressive force coupled to a cam and a follower that work in conjunction with the system, which applies a is counteracting force to the weight of the system about its point of rotation, 
     An overall advantage of orienting this system vertically, as one option, is that less space is taken up by the counterbalance components, compared to the use of a horizontal counterbalance rod system, or even a single torque rod. This additional space due to the vertically mounted counterbalance system can allow clearance for adding other equipment and components to the system where the inventive device is used. An example of such a component is a snowplow, for instance. If the system is used for example on the hood for a vehicle, there is also additional space to facilitate maintenance of the engine compared to a horizontally mounted counterbalance system. 
     The compression device is preloaded to a set force. Throughout any infinite number of points throughout the travel of the system, that force is amplified or minimized as the follower translates (e.g., rolls, slides etc.) over the cam profile. The relationship between the point at which the cam profile acts on the follower and the point at which the compressive force acts on the follower creates the counteracting force relative to the point of rotation in the overall system. 
     The system, as shown and illustrated in various embodiments herein, utilizes a fixed cam attached to a non-moving section of a system (e.g., a truck frame, a doorframe, etc.), and the compression spring counterbalance is attached to the rotating part of the system (e.g., a truck hood, a door, etc.). 
     The system is infinitely customizable, which means that depending on the particular design of the cam profile a truck hood (or other movable element such as the display for a gaming machine) can be designed to open automatically or be partially or even perfectly counterbalanced (made to feel weightless throughout the motion). The moveable element can thus be made to feel like any possibility of desired weight when moved. 
     The system can also be mounted in the reverse configuration where the compression force counterbalance would be fixed and the cam profile would be attached to the rotating or movable part of the system. The system can also be designed to include a hinge or used in conjunction with an external hinge system. 
     The counterbalance assembly is shown in accordance with several exemplary embodiments in the Figures. It should be understood that the counterbalance assembly can be utilized in a variety of applications. Non-limiting examples of applications are vehicle hoods, such as on trucks or cars, heavy doors or lids of containers Or compartments, either in a vehicle or in other applications which require the use of heavy doors or covers that need to be periodically opened and closed, such as lids on a dumpster, bulkhead doors, etc. Also, this invention can be used for any application in which the perceived weight of a component is modified (decreased or increased) at any point along its movement relative to another component. 
     It should be also understood that a single application, for instance a truck hood, can utilize one or more of the counterbalance assemblies or mechanisms described herein in order to facilitate opening or closing the hood. 
     In the present examples the counterbalance mechanism is incorporated on a vehicle hood, in which the front of the hood when in the closed position is generally vertical, and when pulled open from the top or otherwise moved toward an open position, rotates to a more horizontal position, such that engine of the vehicle is accessible. In this example, the compression device is a compression spring, but it can be appreciated by those with skill in the art that any such compression device (e.g., a member that is designed to provide compression) could also comprise a pneumatic cylinder or an air spring, or a hydraulic device, as non-limiting examples. The spring can be a helical spring. It should be also be appreciated that the counterbalance mechanism can utilize a single compression device, for instance one spring, as shown in the first exemplary embodiment, or more than one compression device, such as the two springs shown in the second exemplary embodiment. In addition, as shown in the fourth exemplary embodiment, the force exerted by the compression device may be adjustable. Such adjustability is exemplified as the compression spring shown in the fourth embodiment in which a preload on the compression spring is adjustable by a screw, for instance. 
     Referring generally to the figures, and according to one aspect of the invention, a counterbalance assembly  100  is configured to counterbalance components movable relative to one another, the assembly  100  including a mounting bracket  118  configured to be coupled to one of the components; a follower arm  124  pivotally coupled to a follower arm mounting point  122  on the mounting bracket  118 ; a follower  132  coupled to a follower mounting point  130  on the follower arm  124 ; means for exerting force between a force exerting means mounting point  120  on the mounting bracket  118  and a force exerting means mounting point  128  on the follower arm  124 ; and a cam  136  configured to be coupled to another one of the components in such a way that the follower  132  contacts a cam profile  134  of the cam  136 . 
     According to optional aspects of the assembly, the means for exerting force can be selected from the group consisting of a mechanical spring, a pneumatic Spring, and a hydraulic spring, One spring or a plurality of springs can be used as a means for exerting force. Specifically, the means for exerting force can be a mechanical spring. More specifically, a mechanical spring such as a compression spring or springs  112  can be interposed between the mounting point  120  on the mounting bracket  118  and the mounting point  128  on the follower arm  124 . The assembly  100  can also include a spring guide  113  positioned to guide the spring  112 . The cam profile  134  can include a detent, and the follower  132  can include a roller  132 . If more than one spring  112  is used, each can have an associated cam profile  134 , follower  132 , e.g, a roller  132 , or the more than one spring  112  can be associated together with a common cam profile  134 , follower  132  such as a roller  132 . The cam profile(s)  134  and the spring(s)  112  are selected so as to produce the desired counterbalance force as needed for the particular application. 
     According to another aspect of the invention, a counterbalanced system includes components movable relative to one another and at least one assembly  100  counterbalancing the components relative to one another. The at least one assembly  100  has a mounting bracket  118  coupled to one of the components, a follower arm  124  pivotally coupled to a follower arm mounting point  122  on the mounting bracket  118 , a follower  132  coupled to a follower mounting point  130  on the follower arm  124 , means for exerting force between a force exerting means mounting point  120  on the mounting bracket  118  and a force exerting means mounting point  128  on the follower arm  124 , and a cam  136  coupled to another one of the components in such a way that the follower  132  contacts a cam profile  134  of the cam  136 . The at least one assembly  100  facilitates movement of the components relative to one another. 
     According to optional aspects of the counterbalanced system, one of the components can be a vehicle panel. Also, the vehicle panel can include a vehicle hood  110 . Additionally, one of the components can be oriented at an angle with respect to a horizontal plane in a first position and movable relative to the other one of the components to be oriented at a smaller angle with respect to the horizontal plane in a second position. The component oriented at the angle with respect to the horizontal plane in the first position can be oriented substantially vertically. Also, the components can be pivotally coupled relative to one another in addition to being coupled by the at least one assembly. 
     Referring specifically to  FIG. 1 , which shows a side view of counterbalance assembly  100  mounted to the front of a hood  110 ,  FIG. 1  shows the hood  110  in the vertical position and therefore the hood  110  is closed. The counterbalance assembly  100  is constructed and arranged to pivotally connect the hood  110  to the truck frame (not shown). 
     The counterbalance assembly  100  comprises a compression spring  112 . Although the assembly  100  is shown with a single spring  112 , it should be understood that there could be a plurality of springs  112 . As shown in  FIG. 1 , the spring  112  has an optional internal spring guide  113 , which is constructed and arranged to shorten or lengthen as needed, according to the changing length of the spring, as the compression spring  112  is subjected to more or less compressive force. The spring guide  113  is a telescoping assembly that can expand or retract while guiding the shape of the compression spring  112  to extend along a spring axis. The compression spring  112  has a spring top end  114  and a spring bottom end  116 . Note that the spring bottom end  116  has been illustrated as contacting a nut  117 . The spring guide  113  and the nut  117  are mutually threaded, so that the nut  117  can be moved up or down the shaft of the spring guide  113 . This movement of the nut  117  serves to add or subtract compression to the spring  112 , which adjusts the pre-load on the spring  112 , thereby providing adjustability to the force that the spring  112  exerts to counterbalance the force of gravity. 
     The spring top end  114  is pivotally coupled to a spring mounting bracket  118 , The spring mounting bracket  118  is fixedly mounted to an interior surface of the hood  110 . The spring mounting bracket has a top end  120  and a bottom end  122 . 
     Although not shown in this view, a wire may optionally be threaded through the center of spring  112 , parallel to the spring guide  113 . The wire can be attached to the spring mounting bracket  118 , to provide an additional measure of safety in the event that the spring  112  breaks or comes loose from the spring mounting bracket  118 . Such a wire may be optionally added to any of the embodiments  100 ,  200 ,  300 ,  400 ,  500 ,  600  disclosed herein. 
     As shown in  FIG. 1 , the spring top end  114  is thus pivotally mounted to the spring mounting bracket top end  120 . The spring bottom end  116  is pivotally coupled to a follower arm  124 . The follower arm  124  has three mounting points. These are generally described as a front mounting point  126 , a top mounting point  128 , and a back mounting point  130 . The directions are in reference to the truck, i.e., front is towards the front of the truck, back is towards the back of the truck, and top is towards the top of the truck. 
     The front follower arm mounting point  12 i is pivotally coupled to the spring mounting bracket bottom  122 . The spring bottom end  116  is pivotally coupled to the top mounting point  128 . The back mounting point  130  is rotatably coupled to a follower  132 . The follower  132  is in contact with a profile  134  of a cam  136 . While not shown in  FIG. 1 , the profile  134  can optionally comprise a detent or other surface contour, such as an indent, which would serve to hold or urge the follower  132  in a fixed or stable position, thereby allowing the hood  110  to remain fixed or stable in a position partway between fully opened and fully closed, while still allowing the follower  132  to travel along the profile  134  and thus the hood  110  to be easily moved toward the open or closed position from the position partway between fully opened and fully closed, Additionally, more than one such surface contour can be provided to facilitate stable positioning at multiple intermediate positions. 
     The follower  132  in this embodiment is shown as a rotating disc or a wheel such as the outer surface of a bearing, but it should be understood that the follower  132  could be merely a sliding element, that could optionally be provided with a friction-reducing coating, or another form of cam follower. The cam  136  is fixedly mounted to the truck frame (not shown). Also shown  FIG. 1  is cam hinge point  138  and an optional  3 -bracket  140  extending between the hood and the pivot point. 
     Turning to  FIG. 2 , the  3 -bracket  140  is shown more clearly, in relation to the hood  110  and the cam  136 . The  3 -bracket  140  is pivotally coupled at its front end  142  to the cam  136  at the cam hinge point  138 . The  3 -bracket  140  is fixedly mounted at its back end  144  to a mounting plate  146 . As shown in  FIG. 2 , the 3-bracket back end  144  is mounted to the mounting plate  146  using bolts  148 . The mounting plate  146  is fixedly attached to the hood,  110 . The part  110  may be any other pivotal part of a system such as: a copier lid; a printer lid; medical equipment; diagnostic equipment; a cover for industrial machinery; a food preparation machine such that machinery can be moved out of the way when not in use; a fold-up or fold-down work surface; a flip-up counter such as those in restaurants, bars and other venues; a cover for an armored vehicle hatch such as a hatch on a tank; tiltable displays for gaming machines or gaming systems or other video systems; and any other application in which one component is coupled for movement with respect to another component in a controlled manner with perceived weight management, as non-limiting examples. The attachment of the mounting plate  146  to the hood  110 , or other of the non-limiting examples may be accomplished by any suitable means, for instance, welding or fasteners such as bolts, it should be understood that while a J-bracket  140  is shown, any suitable mounting device can be used and the cam hinge point  138  on the cam  136  could be merged with the spring mounting bracket  118 . This embodiment is shown in  FIGS. 10 and 11 , which are discussed below. 
       FIG. 3  shows a slightly different perspective view of the counterbalance assembly  100 , wherein the  3 -bracket  140  as mounted to the mounting plate  146  is shown more clearly.  FIG. 4  shows a rear view of the counterbalance assembly  100  as mounted on the hood  110 . 
     The mechanism of action of the counterbalance assembly  100  is explained by examining  FIG. 5  and  FIG. 6  as well as  FIG. 7 ,  FIG. 6  shows the counterbalance assembly  100  in the closed position, wherein the hood  110  is vertically disposed. 
     Looking closely at  FIG. 6 , it should be appreciated that the cam profile  134  has a particular contour, or shape. The compression spring  112  is constructed and arranged such that it continually exerts a force on the follower arm  124  and therefore the follower  132  is continually pressed against the cam profile  134 . The length and structure of the compression spring  112 , and therefore the amount of force from the compression spring  112 , is dictated by the position of the follower  132  and follower arm  124 . The shape of the cam profile  134  determines the position of the follower  132  and the follower arm  124 , and therefore the force from the compression spring  112 , which counteracts the moment caused by pivoting the hood  110  from the open or the closed position, which can therefore be varied depending on the shape of the cam profile  134 . 
     As can be seen in  FIG. 7 , which shows the front of the hood  110  in the closed or more vertical position A, as well as in the open, or more horizontal position B in broken lines, one can see that the follower  132  has moved along the cam profile  134 , and as it does so, the force applied by the compression spring  112  can be varied depending on the shape of the cam profile  134 . 
     The compression spring  112  is preloaded to a set force. As noted in this detailed description, this preloaded set force may be adjusted or rendered adjustable, either during manufacture, assembly, or use of the counterbalance system. Throughout any infinite number of points throughout the rotation of the counterbalance assembly  100  caused by the movement of the hood  110 , that force is amplified or minimized as the follower  132  translates (e.g., rolls, slides, etc.) over the cam profile  134 . The relationship between the point at which the cam profile  134  acts on the follower  132  and the point at which the compressive force from the compression spring  112  acts on the follower  132  creates the counteracting force relative to the point of rotation in the overall counterbalance assembly  100 , which is the hinge point  138  on the cam  136 . 
     The counterbalance assembly  100 , as shown, utilizes a fixed cam  136  that is attached to the non-moving section of a system. The non-moving part could be a truck frame as shown above, but could also be a doorframe, for instance. As explained above, the compression spring counterbalance assembly  100  is thus attached to the rotating part of the system (e.g., truck hood, door), but a person skilled in the art can readily appreciate that the operation of the counterbalance assembly  100  could easily be reversed wherein the fixed cam  136  is attached to the rotating part (e.g., hood, door, etc.) and the movable elements (the compression spring  112 , follower arm  124  and follower  132 ) are attached to the truck frame, for instance. A person skilled the art can also understand that the counterbalance assembly  100  as described herein can be used in conjunction with an external hinge system, or the counterbalance assembly  100  as described can itself also include a hinge element. 
     The counterbalance assembly  100  is infinitely customizable depending on the design of cam profile  134 , and a hood  110  or other component could be designed to open automatically or be partially or even perfectly counterbalanced (made to feel lighter or weightless throughout all or part of the motion) or any possibility of desired weight. For example, as noted above, the cam profile  134  can comprise an optional detent (not shown), whereby by the hood  110  can be left partially opened, without having to exert force to hold the hood  110  in a partially open position. 
       FIG. 8  shows a second embodiment of a counterbalance assembly  200 , which operates in substantially the same way as the first embodiment of the counterbalance assembly  100 . The counterbalance assembly  200  has a second compression spring  112 . The second spring  112  is attached to the same follower arm  124  as the other compression spring  112 . The operation of the second embodiment counterbalance assembly  200  is otherwise the same as the first embodiment  100 . 
       FIG. 9  shows another view of counterbalance assembly  200 . In this view, it can be appreciated that the counterbalance assembly  200  (and also, of course the first embodiment assembly  100 , which has a single spring) can be mounted in any orientation, i.e., as shown in  FIG. 9 , the cam  136  is above the springs  112 . Further, it can be seen more clearly in  FIG. 9  that the optional spring guide  113 , has been omitted from each spring  112 . 
       FIG. 10  shows a side view of a third embodiment of a counterbalance assembly  300  which, like the first embodiment  100 , has one spring  112 . In addition, in this embodiment, it can be seen that the optional  3 -bracket  140  has been omitted. Significantly, the hinge point  138  has been merged with the spring mounting bracket  118 , which is mounted on the hood  110 . 
       FIG. 11  shows a perspective view of the third embodiment of the counterbalance assembly  300 . In this view, it can be seen that the hinge point  138  comprises an axle  150  that is configured and arranged to rotatably couple the spring mounting bracket  118  to the cam  136 . 
       FIG. 12  shows a perspective view of a fourth embodiment counterbalance assembly  400 . This fourth embodiment  400  has one compression spring  112 . In this embodiment, the hinge point  138  has been merged with the cam  136 . Thus, in this embodiment, the cam  136  is moveable and would be mounted to the truck hood  110  (not shown), while the mounting bracket  118  is fixed and would be mounted to the truck frame (not shown). 
     As described previously in connection with other embodiments spring  112  may be selected from a wide variety of spring types, including for example a mechanical spring (including for example a helical spring), a pneumatic spring (including for example a gas or air strut or piston), and a hydraulic spring (including for example a hydraulic strut or piston). One spring or a plurality of springs can be used as a means for exerting force. Specifically, in the fourth embodiment  400  illustrated in  FIG. 12 , the means for exerting force can be one or more mechanical springs. 
     As shown in  FIG. 13 , which is a side view of the counterbalanace assembly  400  in the opened position, the cam  136  rotates upward around the hinge point  138  when the truck hood  110  (not shown) is moved to the open position. Also shown in  FIG. 13  is a socket head screw  152 , as well as an upper collar  154 . The screw  152  and the upper collar  154  are mutually threaded, such that when the screw  152  is rotated, the upper collar  154  is moved with respect to the screw  152 . The upper collar  154  is configured and arranged such that it presses on the spring  112 . Thus, when the screw  152  is rotated, the collar  154  moves up or down and thereby changes the preload on the spring  112 , which changes the force that the spring  112  exerts. Note that the head  156  of the screw  152  is more clearly shown in the perspective view  FIG. 12 . Note also that the screw  152  also acts as a guide for the helical spring  112 . 
     Shown in both  FIG. 12  and  FIG. 13  is a screw mount  158 . The screw mount  158  is pivotally mounted to the follower arm  124  at a screw mount pivot point  162 . Also shown in  FIGS. 12 and 13  are a lower collar  164  which holds the spring  112  in pivotal relation at its lower end to the bracket  118 . 
     Turn next to the series of cross-sectional views of counterbalanace assembly  400  in  FIGS. 14, 15 and 16 , which show in cross-section, the movement of the assembly  400  as it is moved from the closed position in  FIG. 14 , to a partially open position in  FIG. 15 , to the open position in  FIG. 16 . As can be seen in these Figures, when the cam  136  rotates upward, the cam follower  132  moves along the cam profile  134 , urged upwards by the force of the compression spring  112  between the lower collar  166  and the upper collar  154  that is attached to the follower arm  124 . 
       FIGS. 17 and 18  show a partially exploded perspective view and an exploded view, respectively, of an exemplary fifth embodiment of a counterbalance assembly  500 . 
     Looking first at  FIG. 17 , the partially exploded view, it can be appreciated that, similar to the second embodiment ( FIG. 8  is exemplary), there are two compression springs  112 . However, in this embodiment, the two springs  112  are mounted in series, rather than in parallel, as they are in the second embodiment. In other words, the springs are generally aligned along a common axis as opposed to being aligned along separate generally parallel axes. 
     The two springs  112  may each have the same compressibility or different compressibility, thereby lending an additional adjustability factor to the counterbalance force that can be achieved with this system. Note that in this partially exploded view  FIG. 17 , there can be seen a spring connector  168  which is located between the two springs  112 . The spring connector  168  is constructed and arranged to hold the two springs  112  in fixed, coaxial relation to each other. While for clarity, the springs  112  in  FIG. 17  are shown as not being in contact with one another, in practice, the spring connector  168  has two projections  170 , each emerging from an opposite side of an annular flange  172 . The projections  170  are constructed and arranged to fit into the center of each spring  112  and the flange  172  is thus pressed tightly between the two springs  112 . The two springs  112  are thus held together along a common axis. The spring connector  168  thus enables the force from both springs  112  to be transferred therebetween. 
     Note also that the follower  132  in  FIG. 17  is not shown in its appropriate position as rotatably attached to the follower arm  124 . Also seen in this partially exploded view are the cam  136  which is rotatably mounted to the spring mounting bracket  118  at the cam hinge point  138 . There are also shown in  FIG. 17 , a bracket spring tip  174  and a follower arm spring tip  176 . These spring tips  174  and  176  allow the springs  112  to be rotatably mounted to the bracket  118  and the follower arm  124 , respectively. 
     Looking next at the exploded view of this fifth embodiment counterbalance system  500  shown in  FIG. 18 , one can see that the spring tips  174  and  176  each have a projection  178 ,  180 , respectively, that are constructed and arranged to fit into the center of the springs  112 , in a manner analogous to the projections  170  on the spring connector  168 . Each spring tip  174  and  176  has a set of legs  182 ,  184 , respectively, and each of these legs  182 ,  184  has through holes  186 ,  188  respectively. 
     As can be seen by examining  FIG. 19 , the through holes  186  are arranged to coincide with through holes  190  in the spring mounting bracket  118 . A set of flanged bearings  192  is thus constructed and arranged to mount into both sets of through holes  186  and  190 , thereby rotatably coupling together the springs  112  and the bracket  118 , via the bracket spring tip  174 . In a similar manner, there are a pair of through holes  194  in the follower arm  124  which are arranged to coincide with the through holes  186  in the follower arm spring tip  176 . Flanged bearings  196  are thus constructed and arranged to mount into both sets of through holes  186  and  194 , thereby rotatably coupling together the springs  112  and the follower arm  124 , via the bracket spring tip  176 . 
     As seen in the exploded view  FIG. 18 , the follower arm  124  has a second set of through holes  198  (only one is visible). These through holes  198  coincide with a set of through holes  202  in the bracket  118 . A set of flanged bearings  204  are constructed and arranged to fit into the through holes  198  and  202 , thereby rotatably coupling together the follower arm  124  and the bracket  118 . The follower  132  in this embodiment can be seen to be in the form of a roller. The follower  132 , as shown in the exploded view  FIG. 18  has a through hole  206 , which a set of bearings  208  fits into. The follower arm  124  has a set of through holes  210  that are constructed and arranged to coincide with the bearings  208  located in the follower through hole  206 . An axle (not shown) is provided that is located in the bearings  208  and the through holes  210  and thus rotatably couples the follower  132  with the follower arm  124 . 
     Looking at the partially exploded view  FIG. 17 , one may observe that the cam  136  is rotatably coupled to the bracket  118  at hinge point  138 , The hinge point  138  on the cam  136  comprises a through hole. There is a pair of through hales  212  in the bracket  118 . The pair of through holes  212  are arranged to coincide with the hinge point/through hole  138  in the cam  136 . Also shown in  FIG. 18  are a hub  214 , as well as two flanged bearings  216 ,  218 . The hub  214  comprises a through hole  220 . The hub  214  fits into the through holes  212  in the bracket  118 , and the hinge point/cam through hole  138 , thus rotatably coupling together the cam  136  and the bracket  118 . The two flanged bearings  216 , fit into the through holes  212  and then into through hole  220  in the hub  214 , and thus serve to prevent the hub  214  from sliding loose from the bracket  118 . 
     Like the other counterbalance assembly embodiments disclosed herein, a person having skill in the art can appreciate that in an embodiment, the bracket  118  may be mounted to a fixed element of a system, such as a hatch opening in a tank, to cite a non-limiting example. The cam  136 , which rotates with respect to the bracket  118  could be mounted to a cover for the hatch opening, which would rotate open and closed. Alternatively, the bracket  118  may be mounted to the rotatable element of a counterbalanced system, while the cam  136  may be mounted to the fixed element of a counterbalanced system. 
     Thus, the principle of operation of this fifth embodiment is therefore for the springs  112  to apply a counterbalancing force, via their rotatable attachment to the follower  132  via the follower arm  124 , to the cam  136  and thence to the hatch cover (as a non-limiting example), or other rotatable element of a system. The cam surface  134  in an embodiment can be shaped and configured so that in conjunction with selection of appropriate springs  112 , for instance, the weight of the hatch cover may be made to feel weightless throughout its travel. This principle also applies in the case when in the bracket  118  is attached to the rotatable hatch cover and the cam  136  is attached to the fixed element such as a side of the hatch. 
     A sixth embodiment counterbalance assembly  600  is shown in perspective views in  FIG. 19  and  FIG. 20 .  FIG. 19  shows the assembly  600  in the closed position and  FIG. 20  shows the assembly  600  in the open position.  FIG. 20  also shows schematically, the components  10 ,  20  of the counterbalanced system that are to be moved pivotably with respect to each other. 
     As shown in  FIG. 20 , component  10  is attached to the cam  136  and component  20  is attached to the bracket. In overview, this sixth embodiment counterbalance system  600  is much like the other five embodiments  100 ,  200 ,  300 ,  400  and  500 , in that this sixth embodiment  600  comprises the components of the cam  136 , the follower arm  124 , and the follower  132 , which travels along the cam profile  134  on the cam  136 . The cam  136  is rotatably attached to the bracket  118  at the hinge point  138 . 
     Note that in this sixth embodiment  600  the bracket  118  is not symmetric and thus the cam  136  is attached on one side only. This embodiment  600  also comprises the spring  112  which is rotatably mounted between the spring mounting bracket  118  at its lower end and the follower arm  124 . This sixth embodiment also comprises the telescoping spring guide  113 , also discussed in the first embodiment  100 . As shown, one may appreciate that the bracket  118  may be, in a non-limiting embodiment, fixedly mounted to component  20  which may be a gaming machine housing, while the cam  136 , which moves, may be fixedly attached to component  10 , which may be a display for the gaming machine. Thus, in an embodiment, the counterbalance assembly  600  may be used to counterbalance the weight of the relatively heavy gaming machine display, so that the display may be easily moved relative to the gaming machine housing so that the display is not in the way for servicing of the electronics, and other equipment in the interior of the gaming machine. 
     One may appreciate that the sixth embodiment counterbalance assembly  600  can be mounted to the exemplary gaming machine in the opposite manner, i.e., the bracket  118  could be mounted to the display for the gaming machine which then is represent by component  20 , while the cam  136  could be mounted to the housing of the gaming machine represented by component  10 . 
     As can be seen in both  FIG. 19  and  FIG. 20 , in this embodiment  600 , the spring guide  113  is threaded. This embodiment, like the first embodiment  100 , comprises the adjustment nut  117 . The adjustment nut  117  is threaded such that it may be rotated and moved up and down the spring guide  113 . Looking again at  FIGS. 19 and 20 , there is seen a washer  222 . The washer  222  is arranged between the spring  112  and the nut  117 . Thus, looking at the perspective views in  FIGS. 19 and 20 , one may appreciate that as the nut  117  is moved up and down on the spring guide  113 , the preload on the spring  112  is thereby adjusted. Thus the counterbalance force that the spring  112  can apply to the follower  132  via the rotatable attachment of the spring guide  113  to the follower arm  124  and thence to the cam  136  via the cam profile  134  may be adjusted as desired, even while the counterbalance assembly is attached to the gaming machine and its display. 
     The shape of a particular cam profile for any of the embodiments disclosed herein may be optionally generated using an algorithm into which variables are input. For example, the force applied by the compression spring(s) or other means, the weight of the movable component, the location of the center of gravity of the movable component, the location of the theoretical or actual point of rotation, and other variables can be input into an algorithm to generate the shape of the cam profile. 
     Various exemplary aspects of the invention may be summarized as follows: 
     Aspect 1: An assembly ( 100 ,  200 ,  300 ,  400 ,  500 ,  600 ) configured to counterbalance components ( 10 ,  20 ) movable relative to one another, the assembly ( 100 ,  200 ,  300 ,  400 ,  500 ,  600 ) comprising: 
     a mounting bracket  118  configured to be coupled to one of the components ( 10 ,  12 ); 
     a follower arm ( 124 ) pivotally coupled to a follower arm mounting point on the mounting bracket ( 118 ); 
     a follower ( 132 ) coupled to a follower mounting point on the follower arm ( 124 ); 
     means for exerting force ( 112 ) between a force exerting means mounting point on the mounting bracket and a force exerting means mounting point on the follower arm; and 
     a cam ( 36 ) configured to be coupled to another one of the components ( 10 ,  20 ) in such a way that the follower contacts a cam profile ( 134 ) of, the cam ( 136 ). 
     Aspect 2: The assembly ( 100 ,  200 ,  300 ,  400 ,  500 ,  600 ) of Aspect 1, the means for exerting force ( 112 ) being selected from the group consisting of at least one mechanical spring, at least one pneumatic spring, and at least one hydraulic spring. 
     Aspect 3: The assembly ( 100 ,  200 ,  300 ,  400 ,  500 ,  600 ) of Aspect 2, the means for exerting force ( 112 ) being at least one mechanical spring. 
     Aspect 4: The assembly ( 100 ,  200 ,  300 ,  400 ,  500 ,  600 ) of Aspect 3, the at least one mechanical spring being a compression spring or compression springs interposed between the mounting point on the mounting bracket and the mounting point on the follower arm. 
     Aspect 5: The assembly ( 100 ,  200 ,  300 ,  400 ,  500 ,  600 ) of Aspect 3, further comprising a spring guide ( 113 ) positioned to guide at least one of the at least one spring ( 112 ). 
     Aspect 6: The assembly ( 100 ,  200 ,  300 ,  400 ,  500 ,  600 ) of Aspect 1, the cam profile ( 134 ) further comprising a detent. 
     Aspect 7: The assembly ( 100 ,  200 ,  300 ,  400 ,  500 ,  600 ) of Aspect 1, wherein the follower ( 132 ) comprises a roller. 
     Aspect 8: A counterbalanced system comprising: 
     components ( 10 ,  20 ) movable relative to one another; and 
     at least one assembly ( 100 ,  200 ,  300 ,  400 ,  500 ,  600 ) counterbalancing the components ( 10 ,  20 ) relative to one another, the at least one assembly ( 100 ,  200 ,  300 ,  400 ,  500 ,  600 ) having
         a mounting bracket ( 118 ) couple to one of the components ( 10 ,  20 ),   a follower arm ( 124 ) pivotally coupled to a follower arm mounting point on the mounting bracket ( 118 ),   a follower ( 132 ) coupled to a follower mounting point on the follower arm ( 124 ),   means for exerting force ( 112 ) between a force exerting means mounting point on the mounting bracket ( 118 ) and a force exerting means mounting point on the follower arm ( 124 ), and   a cam ( 136 ) coupled to another one of the components ( 10 ,  20 ) in such a way that the follower ( 132 ) contacts a cam profile ( 134 ) of the cam ( 136 );       

     wherein the at least one assembly ( 100 ,  200 ,  300 ,  400 ,  500 ,  600 ) facilitates movement of the components ( 10 ,  20 ) relative to one another. 
     Aspect 9: The counterbalanced system of Aspect 8, wherein one of the components ( 10 ,  20 ) is a vehicle panel and the other of the components ( 10 ,  20 ) is a vehicle. 
     Aspect 10: The counterbalanced system of Aspect 9, wherein the vehicle panel comprises a vehicle hood. 
     Aspect 11: The counterbalanced system of Aspect 8, wherein the counterbalanced system is a gaming machine and one of the components ( 10 ,  20 ) is a gaming machine display and the other of the components ( 10 ,  20 ) is a housing of the gaming machine. 
     Aspect 12: The counterbalanced system of Aspect 8, wherein one of the components ( 10 ,  20 ) is oriented at an angle with respect to a horizontal plane in a first position and is movable relative to the other one of the components ( 10 ,  20 ) to be oriented at a smaller angle with respect to the horizontal plane in a second position. 
     Aspect 13: The counterbalanced system of Aspect 12, wherein the component ( 10 ,  20 ) oriented at the angle with respect to the horizontal plane in the first position is oriented substantially vertically. 
     Aspect 14: The counterbalanced system of Aspect 8, wherein the components ( 10 ,  20 ) are pivotally coupled relative to one another in addition to being coupled by the at least one assembly. 
     Aspect 15: The assembly ( 100 ,  200 ,  300 ,  400 ,  500 ,  600 ) of Aspect 1, the means for exerting force ( 112 ) being a spring. 
     Aspect 16: The assembly ( 100 ,  200 ,  300 ,  400 ,  500 ,  600 ) of Aspect 15, the spring being selected from the group consisting of at least one mechanical spring, at least one pneumatic spring, and at least one hydraulic spring. 
     Aspect 17: The assembly ( 100 ,  200 ,  300 ,  400 ,  500 ,  600 ) of Aspect 16, the mechanical spring comprising a helical spring. 
     Aspect 18: The assembly ( 100 ,  200 ,  300 ,  400 ,  500 ,  600 ) of Aspect 17, the force exerted by the helical spring being adjustable. 
     Aspect 19: The assembly ( 100 ,  200 ,  300 ,  400 ,  500 ,  600 ) of Aspect 18, the force exerted by the helical spring being adjustable with a screw ( 152 ). 
     Aspect 20: The assembly of Aspect 18, the force exerted by the helical spring being adjustable with a nut ( 117 ). 
     Aspect 21: The assembly ( 100 ,  200 ,  300 ,  400 ,  500 ,  600 ) of Aspect 16, the pneumatic spring comprising a pneumatic cylinder or an air spring. 
     Aspect 22: The assembly ( 100 ,  200 ,  300 ,  400 ,  500 ,  600 ) of Aspect 16, the hydraulic spring comprising a hydraulic cylinder. 
     Aspect 23: An assembly ( 100 ,  200 ,  300 ,  400 ,  500 ,  600 ) configured to counterbalance components ( 10 ,  20 ) movable relative to one another, the assembly ( 100 ,  200 ,  300 ,  400 ,  500 ,  600 ) comprising: 
     a mounting bracket ( 118 ) configured to be coupled to one of the components ( 10 ,  20 ); 
     a follower arm ( 124 ) pivotally coupled to a follower arm mounting point. on the mounting bracket ( 118 ); 
     a follower ( 132 ) coupled to a follower n mounting point on the follower arm ( 124 ); 
     a spring ( 112 ) positioned to exert a force between a spring mounting point on the mounting bracket ( 118 ) and a spring mounting point on the follower arm ( 124 ); and 
     a cam ( 136 ) configured to be coupled to another one of the components ( 10 ,  20 ) in such a way that the follower ( 132 ) contacts a cam profile ( 134 ) of the cam ( 136 ). 
     Aspect 24: The assembly ( 100 ,  200 ,  300 ,  400 ,  500 ,  600 ) of Aspect 23, the spring ( 112 ) being selected from the group consisting of at least one mechanical spring, at least one pneumatic spring, and at least one hydraulic spring. 
     Aspect 25: The assembly ( 100 ,  200 ,  300 ,  400 ,  500 ,  600 ) of Aspect 24, the at least one spring ( 112 ) being at least one mechanical spring and the force between the spring mounting point on the mounting bracket and the spring mounting point on the follower arm being adjustable. 
     Aspect 26: The assembly ( 100 ,  200 ,  300 ,  400 ,  500 ,  600 ) of Aspect 25, the at least one mechanical spring ( 112 ) being at least one helical spring and the force being adjustable with at least one screw ( 152 ). 
     Aspect 27: The assembly of ( 100 ,  200 ,  300 ,  400 ,  500 ,  600 ) Aspect 25, the at least one mechanical spring ( 152 ) being at least one helical spring and the force being adjustable with at least one nut ( 117 ). 
     While preferred embodiments of the invention have been shown and described herein, it will be understood that such embodiments are provided by way of example only. Numerous variations, changes and substitutions will occur to those skilled in the art without departing from the spirit of the invention. Accordingly, it is intended that the appended claims cover all such variations as fall within the spirit and scope of the invention.