Link 1 turns about fixed axis B and is connected by turning pairs C and D to gears 3 and 2. Rotary latches A, of segment shape, are connected to gears 2 and 3 by systems of levers. The lever system connected to gear 2 is similar to that connected to gear 3. Therefore, when a torque is applied to link 1, the forces acting on the lever systems transmitting motion to latches A are equal in magnitude and counterbalance each other. The forces of resistance applied to latches A also counterbalance one another. As a result, even though the mechanism has several degrees of freedom, there is certainty of motion when link 1 is turned. Latches A turn about their fixed axes and lock the refrigerator door.
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