Abstract:
A waste container having a body and a lid pivotably connected to the body. The lid includes a gravity activated locking mechanism having a latch that engages the lid to the body when the container is in an upright position. The locking mechanism rotates to disengage the latch and allow the lid to open when the container is inverted for dumping the waste. The waste container further including a slideable member that is engageable with a locking member when the container is not in an upright position or inverted for dumping, to prevent rotation of the locking mechanism and opening of the lid.

Description:
CROSS-REFERENCE TO RELATED APPLICATIONS 
     The present application claims the benefit of U.S. Provisional Application Ser. No. 61/768,049 filed Feb. 22, 2013, the contents of which are incorporated herein by reference. 
    
    
     FEDERALLY SPONSORED RESEARCH OR DEVELOPMENT 
     N/A 
     FIELD OF THE INVENTION 
     The present invention generally relates to a latch mechanism for a waste container having a body and a lid pivotably connected to the body; and more particularly to a latch mechanism for a waste container that is gravity activated for use with automatic features or equipment of a waste collection truck. 
     BACKGROUND OF THE INVENTION 
     One problem with waste containers that are stored outside and that contain organic materials is the entry of pets, rodents, and vermin. In particular, raccoons have been shown to be very skillful in the art of getting to the contents of communal and commercial waste containers. 
     Some containers, especially those designated for the collection of organic waste, have elaborate latch mechanisms that make it difficult for animals to actuate, but allow the human user to open and close the lid with one hand for filling. 
     To save costs, more and more municipalities use automated trucks to collect waste. These trucks are manned by one driver, who operates the unloading of containers via joystick-controlled grab arms and cameras. This means that any latch mechanism on the container needs to be automatically unlatched during dumping because the driver does not leave the truck in normal operation. 
     One known solution to the problem is to add a sliding weight to the arm of the truck that actuates a latch on the container. A downside to this type of system is that it requires a specialized arm or a modification to existing dump trucks. 
     To overcome the need to have to modify the dump system, gravity latches have been developed that unlock the lid of a waste container when a certain tilt angle is reached. Known mechanisms include: U.S. Pat. No. 5,094,358 LOCKING MECHANISM FOR CONTAINER LID; U.S. Pat. No. 5,474,341 GRAVITY ACTUATED CONTAINER LOCK; U.S. Pat. No. 5,415,314 GRAVITY LOCKING MECHANISM EMPLOYING FIRST AND SECOND PENDULUMS FOR SECURING THE LID OF A REFUSE CONTAINER; and FRANZEN International offers a gravity lock for trash carts (http://www.franzenint.com/trash-bin-gravity-locks.html). 
     The present invention provides an improved waste container with a gravity activated latch mechanism. 
     SUMMARY OF THE INVENTION 
     The present invention provides a waste container having a container body and a lid pivotably attached to the container body. The waste container is provided with a gravity locking mechanism in the lid for locking the lid to the container body when in an upright position, and for disengaging the lock when the container is inverted (typically by automatic dumping equipment). Inverting the container causes a weight in the mechanism to rotate a lever connected to a latch to disengage the latch and allow the lid to open. 
     In accordance with one embodiment, a waste container with a gravity locking mechanism is provided. The waste container includes a container body having an open top portion and a catch on a front portion of the top portion. A lid is pivotably connected to the top portion of the container body. A locking mechanism is connected to the lid. The locking mechanism includes a rotatable member having an axis of rotation; a latch configured to engage the catch when the lid is pivoted to a closed position and a weight. A lever connects the rotatable member, latch and weight. The locking mechanism is configured so that placement of the container in an upside down position causes the weight to rotate the lever about the axis of rotation of the rotatable member to disengage the latch from the catch to enable opening of the lid. 
     The rotatable member can be positioned at a first end of the lever above the latch. The weight can be positioned at a second end of the lever. The weight can be a separate piece of material, such as steel or other similar material, and can be secured to the locking mechanism by a push-in fastener or other similar means. Alternatively, the weight does not have to be a separate piece of material. Instead, the weight can be made from the same material used for the lever and be integrally formed therewith. 
     The waste container can include a button in a front portion of the lid. The button can be slideably configured to disengage the latch from the catch when the container is in an upright position to enable opening of the lid. A variety of other mechanisms could also be used to allow a user to manually unlatch the lid when upright. For example: a rotatable knob or key, a secondary lever, or a rigid extension of the main lever that protrudes through the lid, or other known means could also be used. 
     The container body can include wheels connected to a lower portion of the container body to facilitate movement of the container. Additionally, the container body can include features to facilitate use with automatic dumping equipment. The lid can also be provided with a handle. 
     The lid can also be provided with a cover plate having a portion positioned between the locking mechanism and the container body. The cover plate separates the locking mechanism from the interior of the container body and prevents waste from contacting or otherwise interfering with the locking mechanism. 
     In accordance with another aspect of the invention, a waste container with a gravity activated latch in the lid is provided. The waste container comprises a container body having a bottom and a sidewall extending upward from the bottom to a top opening. The container body includes an inwardly directed protrusion proximate the top opening. A lid is pivotably connected at a first end to a first side of the top opening of the container body. A lock having a rotatable member is connected to an interior portion of the lid proximate a second end of the lid opposed from the first end. A first arm extends from the rotatable member. The first arm has a latch element for engaging the protrusion on the container body when the waste container is in an upright position and preventing the lid from opening. A second arm extends from the rotatable member toward the interior of the container. 
     The first arm extends generally vertically downward when the lid is in a closed position over the opening and the waste container is in an upright position. The second arm extends generally horizontally when the lid is in a closed position over the opening and the waste container is in an upright position. The first arm and second arm are preferably at a right angle. 
     The second arm includes a first end connected to the rotatable member and a second end distal from the rotatable member. A weight is connected to the second arm proximate the second end. The weight can be steel or some other suitable material. The weight is connected to the second arm by a push-in fastener or can be molded into the second arm. 
     A cover plate can be connected to an interior portion of the lid. The cover plate separates the second arm from the interior of the container body when the lid is in a closed position. The cover plate includes an opening to enable the first arm to engage the protrusion of the container body. The cover plate prevents materials in the container body from interfering with rotation of the lock. 
     The waste container can further comprise a moveable member connected to one of the lever and the lid, and a locking member connected to the other of the lever and the lid that is engageable with the moveable member to prevent rotation of the rotatable member. The moveable member moves to a locking position when the container is not in one of an upright position and an upside position (e.g., when the container is pushed on its side). 
     The container body can be formed from plastic or other similar materials. Similarly, the lid can also be formed from plastic or other similar materials. 
     In accordance with another embodiment of the invention, a waste container with a gravity latch that will not open if the container is moved into an improper position (e.g., on its side) is provided. The waste container comprises a container body having a bottom wall, a side wall extending upward from the bottom wall, and an open top. A lid is pivotably connected to the open top at one end. A gravity locking mechanism having a latch arm, a rotatable hinge portion, a latch connected to a first end of the latch arm and a first weight connected to the latch arm is connected to the lid. The latch is engageable with the container body when the container is in an upright position (keeping the lid locked to the container body) and disengageable with the container body when the container is in an upside down position by rotation of the latch arm due to gravity (allowing the lid to open to dispel any contents of the container body). The waste container further comprises a moveable (e.g., slideable or pivotable) member connected to one of the lid and the latch arm, and a locking member on the other of the lid and the latch arm. The moveable member is configured to move to engage the locking member when the container is not one of upright or upside down (e.g., pushed onto its side) to prevent rotation of the locking mechanism and unwanted opening of the lid. Moreover, the moveable member and locking structure can be used on containers having different gravity or other types of locking mechanisms. 
     The moveable member can be a second weight having a central opening allowing for slideable movement about a post. The locking structure can be a ledge positioned to engage the weight when the container is moved to an improper position (which causes the weight to slide to an engaging position). The second weight can be positioned on the latch arm (e.g., by the first weight) and the locking structure can be a ledge connected to the lid or a portion of the cover plate. 
     The waste container can further comprise a spring (such as a torsion spring) connected to the rotatable hinge portion, the latch arm and the latch. This enables movement of the latch with respect to the latch arm upon application of a force on the latch (e.g. by a push button) sufficient to overcome the spring force. This allows for opening of the container regardless of rotation of the latch arm of the locking mechanism (e.g., when the moveable member is engaged with the locking structure). 
     Further aspects of the invention are disclosed in the Figures and are described herein. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
       To understand the present invention, it will now be described by way of example, with reference to the accompanying figures in which: 
         FIG. 1  is a perspective view of a first embodiment of a waste container having a body and lid pivotably connected to the body; 
         FIG. 2  is a cross-sectional view of a top portion of the container of  FIG. 1  showing a latch feature in a latched position; 
         FIG. 3  is a cross-sectional view of the top portion of the container of  FIG. 1  showing the latch mechanism in an unlatched position; 
         FIG. 4  is a cross-sectional view of the top portion of the container of  FIG. 1  showing how gravity operates the latch mechanism to move it to the unlatched position to allow the lid to open during an automatic dumping operation; 
         FIG. 5  is a cross-sectional plan view of the top portion of a second embodiment of a waste container having a body and lid pivotably connected to the body in an upright position; 
         FIG. 6  is perspective cross-sectional view of the top portion of the container of  FIG. 5  in an inverted position; 
         FIGS. 7A, 7B and 7C  are perspective views of a secondary weight used in the container of  FIG. 5  in a first position, a second position and a third position, respectively; 
         FIG. 8  is an exploded view of a pivoting end of a latch arm of the container of  FIG. 5 ; 
         FIG. 9  is a cross-sectional view of the container of  FIG. 5  with the secondary weight positioned to catch the ledge and prevent the latch arm from rotating (e.g., when the container is on its side or back); 
         FIG. 10  is a cross-sectional view of the container of  FIG. 9  with button depressed to unlatch the lid by independently rotating and moving the hook with respect to the latch arm; and 
         FIG. 11  is a cross-sectional view of the container of  FIG. 9  in an upside down position showing the secondary weight allowing the latch arm to rotate. 
     
    
    
     DETAILED DESCRIPTION 
     While this invention is susceptible of embodiments in many different forms, there is shown in the Figures and will herein be described in detail preferred embodiments of the invention with the understanding that the present disclosure is to be considered as an exemplification of the principles of the invention and is not intended to limit the broad aspect of the invention to the embodiments illustrated. 
     As illustrated in  FIG. 1 , a waste container  10  includes a container body  12  and a lid  14  pivotably connected at one end to the container body  12  by a hinge element  16 . The container body  12  includes a bottom and sidewalls extending upward from the bottom to an open top portion (which can be selectively covered by the lid  14 ). The container body  12  also includes wheels  18  on a lower portion of the body  12 . The lid  14  includes a handle  20  extending from an upper surface of the lid  14 . The container body  12  and lid  14  can be formed from plastic or other similar or suitable materials. 
     Referring to the cross-section of  FIG. 2 , a gravity actuated locking or latching mechanism  22  (i.e., lock) is shown. The mechanism  22  includes a latch lever  4  rotatably mounted to the lid  14  of the waste container  10 . At a first end, the lever  4  includes a rotatable member  4   a  having an axis of rotation mounted to the underside of the lid  14  proximate the location of the handle  20 . The rotatable member  4   a  having the axis of rotation can be a cylindrical axle or other similar structure that allows rotation of the lever and latch. At a second opposing end, the lever  4  includes a weight  5 . 
     The locking mechanism  22  can be formed primarily out of plastic or other similar or suitable material. However, the weight  5  in the locking mechanism  22  can be steel (or other suitable material) that is fastened to the lever  4  by a push-in fastener  6 . Alternatively, the weight  5  could be overmolded into the plastic of the lever  4 , or could be fastened to the lever  4  by different means than those shown. Alternatively, the weight can be integrally formed with the lever (e.g., the same material). In this embodiment, the lever can be formed from a material with sufficient weight to enable rotation due to gravity. 
     A latch hook  4   b  is provided at the first end of the lever  4  below the rotatable member  4   a . The latch hook  4   b  is designed to cooperate with an inwardly projecting protrusion, such as a catch  24  formed at the top of the container body  12 . When the lid  14  is down covering the opening of the container body  12  (i.e., when the waste container  10  is right-side-up) the latch hook  4   b  engages the catch  24  and locks the lid  14  to the container body  12 . The weight  5  at the second end of the lever  4  provides a downward force on the end of the lever  4  which causes the rotatable member  4   a  to rotate clockwise (in cross-section) and keeps the latch hook  4   b  in place against the catch  24  in this upright position. 
     A push button  3  is slideably mounted at the front of the lid  14  to enable a user to manually disengage the latch hook  4   b  and open the lid  14  when the waste container  10  is in the upright position. As illustrated in  FIG. 3 , pushing in the button  3  pivots the latch hook  4   b  back and upward to disengage the catch  24  on the container body  12 . The force to push the button  3  in this embodiment is affected by the weight  5 , the distance from the weight  5  to the axis of rotation  4   a , and the distance from the axis of rotation  4   a  to the point where the button  3  makes contact with the latch hook  4   b . The amount of force needed to open the lid  12  can be adjusted by altering any of these three variables. The lid  14  is provided with a space for the weight  5  in the pivoted-unlatched position. When the lid  14  is lowered, the latch  4   b  will reengage the catch  24  and lock the lid  14  to the container body  12 . 
     A cover plate  7  is positioned below the lever  4 . A portion of the cover plate  7  separates the locking mechanism  22  from the interior of the waste container body  12 . This protects the locking mechanism from contacting waste placed in the container, and prevents such waste from interfering with the mechanism during operation. 
     The locking mechanism  22  is configured to automatically (i.e., via gravity) unhook the latch hook  4   b  when the container  10  is turned upside down (e.g., by a waste disposal vehicle or other similar apparatus). As illustrated in  FIG. 4 , when the container  10  is turned upside down, the weight  5  causes the lever  4  to pivot about the axis of rotation  4   a  in a counter-clockwise direction which disengages the latch hook  4   b  from the catch  24 . This allows the lid  14  to open under gravity. 
     As illustrated in  FIGS. 1-4 , the lever  4  has a first vertical arm (when the lid is closed and the container is in an upright position) extending downward from the rotatable member  4   a  with the latch at an end of the arm, and a horizontal arm extending from the rotatable member  4   a  toward an interior of the waste container. The weight  5  is at a distal end of the second arm. The first and second arms form a right angle at the rotatable member  4   a.    
     One potential shortcoming of the waste container  10  shown in  FIGS. 1-4 , is that the design may not prevent the lid  14  from opening when the container falls over on its side (e.g., accidentally by a person placing waste in the container, or by a raccoon or other animal attempting to get inside). In such instances, gravity or other centrifugal forces may pivot the weighted latch lever  4  out of its locked position, which can result in the unintentional opening of the lid  14 . This can lead to spillage of, or access to, the contents of the container  10 . 
       FIGS. 5-11  illustrate another embodiment of a waste container  10 ′ with a gravity latch mechanism. The waste container  10 ′ includes a lid  1  pivotably connected at one end to a container body  12 . 
     The lid  1  includes a gravity actuated locking or latching mechanism  22 ′ having a latch arm  30  and a separate latch hook  32  (that is, unlike the container of  FIGS. 1-4 , the latch arm  30  and latch hook  32  are two separate pieces). The latch arm  30  and latch hook  32  are connected through a hinge tube  34  surrounding an axle  35 . The axle  35  is fastened to the lid  1  and allows the latch arm  4  and hook  32  to rotate together about the axle  35  in the manner discussed above. 
     Additionally, the latch hook  32  in the embodiment of  FIGS. 5-11  can move (i.e., rotate) relative to the latch arm  30  by a small amount (approximately 12° to 15°). A torsion spring  36  surrounds the hinge tube  34  and exerts a rotational force between the latch arm  30  and the latch hook  32 . The torsion spring  36  is configured to bias the hook  32  to extend generally perpendicular to the latch arm  30 . An exploded view of these components (i.e., the pivoting end of the latching mechanism  22 ′) is shown in  FIG. 8 . Although a torsion spring is shown, other types of springs or spring-like elements (e.g., compression or elastomeric springs) can be used. 
     A first, primary weight  5 ′ is connected to the latch arm  30  at an end of the latch arm  4  distal from the end proximate the hook  32 . The first primary weight  5 ′ functions in the same manner as the weight  5  shown with respect to the embodiment in  FIGS. 1-4 . That is, the weight  5 ′ causes the latch arm  30  and hook  32  to engage the catch  24  on the container body  12  when in the upright position and to rotate the latch arm  30  and hook  32  when upside down, enabling the lid  1  to open. 
     In addition to the first primary weight, the latching mechanism  22 ′ of the embodiment of  FIGS. 5-11  includes a second, secondary weight  38 . The second weight  38  is shaped like a ring washer having a central opening  42 . As illustrated in  FIGS. 6 and 7A -C, the center of the second weight  38  is positioned over a post or projection  40  extending from a portion of the first weight  38 . 
     A cover plate  7 ′ separates the mechanism  22 ′ from the interior of the container body  12 . The cover plate  7 ′ includes a ledge  44  positioned above the first and second weights  5 ′ and  38  (i.e., in the direction of rotation of the weights) as shown, for example, in  FIG. 6 . In this regard, the ledge  44  can be any other locking feature or structure that is capable of engaging the weight  38  (when it has moved to an appropriate position as discussed herein) and preventing the latch arm from rotating. 
     As illustrated in  FIGS. 7A-C , the second or secondary weight  38  can slide freely about the projection  40  in a generally U-shaped pocket  48  formed by the primary weight  5 ′ and the latch arm  30 . In this regard, weights having other shapes with a central opening can also be used. 
       FIGS. 7A-C  show the position of the secondary weight  38  relative to the primary weight  5 ′ (which is locked in position with respect to the latch arm  30 ), depending on the orientation of the cart  12 .  FIG. 7A  shows the secondary weight  38  in a first position—wherein the weight  38  rests along a bottom of the U-shaped pocket  48 —when the container  12  is in an upside down position for dumping its contents.  FIG. 7B  shows the secondary weight  38  in a second position—wherein the weight  38  rests along one of the sides of the U-shaped pocket  48 —when the container  12  is laying on one of its sides.  FIG. 7C  shows the secondary weight  38  in a third position—wherein the weight  38  is not resting against the walls of the U-shaped pocket  48 —when the container  12  is in a normal upright position (or laying on its back with the handle down). 
     When the container is moved sideways or backward the secondary weight  38  extends beyond the edge of the U-shaped pocket  48  and the back edge of the primary weight  5 ′—as is the case of  FIGS. 7B and 7C . In these instances, the secondary weight  38  catches the ledge  44  and prevents the latch arm  4  and hook  32  from rotating because of the primary weight  5 ′ and thus keeps the lid  1  locked to the container body  12 . 
       FIG. 9  illustrates operation of the secondary weight  38  when the container is on its side or back. As shown, the secondary weight  38  moves to the edge of the pocket  48  formed by the primary weight  5 ′. In this position, a portion of the secondary weight  38  is positioned under the ledge  44  in the cover plate  7 ′. This portion will contact the ledge  44  and prevent the latch arm  30  from rotating, and in turn, rotating the latch  32 , keeping the lid  1  in a closed position. 
     As illustrated in  FIG. 10 , the lid  1  can still be opened in such situations by utilizing the push button  3 —even if the secondary weight  38  catches the ledge  44  (which prevents the latch arm  30  from rotating). This is because the hook  32  is a separate component from the latch arm  30  (i.e., it is not rigidly connected to or an integral part of the latch arm as in the embodiment of  FIGS. 1-4 ) and can move independently from the latch arm  30 . As discussed above, the hook  32  is connected to the latch arm  30  via the hinge tube  34 , axle  35  and torsion spring  36 , and therefore can rotate relative to the latch arm  30 . The force needed to push the button  3  and move the hook  30  is determined by the strength of the torsion spring  36 . 
     As illustrated in  FIG. 11 , when the container is upside down, the secondary weight  38  slides to a position in the pocket  48  that does not overlap the ledge  44 . Accordingly, the primary weight  5 ′ will cause the latch arm  30  to rotate—which will cause the hook  32  to rotate and unlatch the lid  1  from the container body  12 . 
     While the secondary weight is shown as a ring with a central opening, other shapes or configurations can be used. Moreover, the secondary weight could be replaced with a pivoting member or mechanism, or some other similar moveable member or mechanism. Additionally, the moveable and locking structures could be reversed so that the secondary weight, or other pivotable or moveable member or mechanism, can be connected to the lid and can engage a ledge or other type of locking member on the latch arm. 
     Many modifications and variations of the present invention are possible in light of the above teachings. It is, therefore, to be understood within the scope of the appended claims the invention may be protected otherwise than as specifically described.