Lock device

A lock device, comprising:

• a lock mechanism provided on one of two members to be engaged with each other;
• and
• a striker provided on the other of the two members,
• wherein the lock mechanism comprises a base plate having a recess that can receive the striker;
• a hook rotatably attached to the base plate via a shaft, the hook, when rotated, forming a locked condition in which the striker is held between the hook and the recess of the base plate or an unlocked condition in which the hook is spaced away from the striker;
• a pawl rotatably attached to the base plate via a shaft, the pawl maintaining the hook in the locked condition when the pawl is rotated to a position in which the pawl can engage the hook;
• a lock spring provided between the hook and the pawl, the lock spring imparting a biasing force to the hook so as to bias the hook in a direction that the unlocked condition is formed;
• a cam rotatably supported via the shaft of the pawl so as to be coaxially rotatable with the pawl, the cam further pressing the hook in the locked condition in a locking direction;
• and a push spring provided between the cam and the base plate, the push spring biasing the cam so as to press the hook,
• wherein a first contact point in which the pawl contacts the hook in the unlocked condition by an elastic force of the lock spring and a second contact point in which the cam contacts the hook in the unlocked condition by an elastic force of the push spring are separately set at different positions, and
• wherein assuming that a value obtained by dividing a distance between a rotation center of the hook and the first contact point along a direction of a normal with respect to an arc of the hook and the pawl at the first contact point by a distance between the normal and a rotation center of the pawl is A, and that a value obtained by dividing a distance between the rotation center of the hook and the second contact point along a direction of a normal with respect to an arc of the hook and the cam at the second contact point by a distance between the normal and the rotation center of the pawl is B, the second contact point is set such that B is smaller than A.