Anti-tip hinge device and method

In combination,

• a unit having a cavity opening in the front wall thereof, and a door pivotally mounted to said unit to close said opening, wherein said door has sheath means, and
• a pair of release hinge devices mounting said unit door to close said cavity, each of said release hinge devices, comprising:
• a lever arm having a first end and a second end,
• counterbalance spring means having one end attached to said first end of said lever arm and another end attached to said unit for allowing pivotal movement of said door in the opening and closing of said cavity and for retaining said door in a generally horizontal, cantilever position in said opening of said cavity,
• cam follower means rotatably mounted at said second end of said lever arm,
• channel means in said sheath means of said door and having elongated slot means and connected to said door and to said unit for said pivotal movement of said door relative to said unit,
• cam means mounted in said channel means and having a recess and adjacent ramp means and being disposed between said slot means of said channel means,
• said cam follower means engageable with said cam means and having mounting means for said rotatable mounting of said cam follower means to said lever arm and engageable with said slot means, and being in an operative position when in said recess of said cam means, and
• biasing means connected to said cam means and said channel means for allowing pivotal movement of said cam means and movement of said cam follower means from said recess and along said ramp means of said cam means, and for causing said mounting means of said cam follower means to move along said slot means of said channel means to interrupt the effect of said counterbalance spring means on said pair of hinge devices and to cause said door of said unit to be angularly displaced from said horizontal, cantilever position when an overload is applied to said door.

An anti-tip release mechanism in a hinge device which includes a lever for connecting a door to a unit and which includes a hinge member for pivotally securing said door to said unit, which said release mechanism automatically releases said door when an excessive load is placed on said door when said door is in an open cantilever position, thereby preventing said unit from falling over, said release mechanism comprising:

• cam means mounted in said door for pivotal movement therein, and having a recess and adjacent ramp means,
• cam follower means engageable with said cam means and being in an operative position when in said recess of said cam means,
• said cam follower means being mounted to one end of said lever, and
• biasing means connected to said cam means and to said hinge device for said pivotal movement of said cam means and movement of said cam follower means from said recess and along said ramp means of said cam means to cause said door when in said open position to be angularly displaced when said overload is applied to said door.

A method for safely releasing a door pivotally connected to a unit by a hinge device when an excessive load is placed on said door when in an open condition, to prevent said unit from falling over, the steps comprising:

• attaching a first part of said hinge device to said unit and a second part to said door,
• providing a lever arm connected at one end to a counterbalance spring means in said unit and cam follower means mounted on the other end of said lever arm,
• providing cam means in said second part of said hinge device and having a recess and adjacent ramp means,
• engaging said cam follower means in said recess of said cam means for an operative condition of said door from a generally vertical position parallel to said unit, to a generally horizontal and cantilevered position, relative to said unit,
• providing biasing means connected to and on either side of said cam means for allowing pivotal movement of said cam means,
• applying said excessive load on said door, and causing said biasing means in close proximity to the cantilevered end of said door to be compressed and said cam means to be pivotted thereby forcing said cam follower means to be snapped out of said recess of said cam means and to engage and travel along said ramp portion of said cam means, resulting in said door being released from the effect of said hinge device.