| 摘要 |
<p>DOOR JACK A door jack comprises a fixed vertical clamping member and a movable clamping member including a horizontal projection for receiving the weight of the door. Guide surfaces provided on the movable clamping member and on a support therefor guide movement of the clamping member under the weight of the door so that it moves toward the stationary plate to clamp the door therebetween. A spring is positioned between the movable clamping member and the support in a recess of the clamping member for withdrawing the movable clamping member when the weight of the door is removed.</p> |
