| 摘要 |
<p>In a case when a cylinder is used for door's control, it is known that if the door is desired to be kept opened at a certain position, a reliable stopper against retraction of the cylinder rod is needed. In this invention, devices with secure locking mechanisms are added to the cylinders. The simple one just has a locking plate being pressed onto the cylinder rod by thightening a screw. The others involve self-jamming parts being pressed onto the central rods of the cylinders by a spring or other mechanical means. When the cylinder rod tends to retract, the friction between the rod and the self-jamming part tends to move the self-jamming part in a direction to cause even more jamming. This provided a mean towards secure stopping of the cylinder rod's retraction so that people will not have to worry about the closing of the storm door when they are moving large items, like furniture into or out from houses. Also people can keep the storm doors opened as they desire for the following people to come. However, when the storm doors are being pushed from inside the houses, the forces of the self-jamming parts against the cylinder rods will be much weaker so as to ensure that the doors can be pushed out for safety during emergency. Similarly, if this kind of retraction stopper is temporary or permanently attached to the central rod of a pneumatic cylinder holding the hood of an automobile, this will prevent the hood from dropping down unexpectedly due to the worn out hood lifting cylinder and thus prevent causing serious bodily injuries.</p> |
