Patent ID: 7298274
Filing Date: 2007-11-20
Classification: G09F,Y10T

Abstract:
1. A passive RFID-based electronic seal comprises: a lower body, comprising: a lower sleeve having a slot placed within and a first inner screw thread implemented at a front end of the slot, and a first spring, a retaining block and a first antenna placed sequentially; and a central sleeve having a step-like hole passing therethrough and a second inner screw thread placed at a front end of the central sleeve, and an first outer screw thread placed at a rear end of the central sleeve, and a retaining plate, a second spring and a push ring placed inside the central sleeve sequentially, a chip having two ends attached to a socket and placed inside the central sleeve, then a pipe placed at a front end of the socket and a third spring and a first push tube placed sequentially inside the pipe, a guide pin passing through the middle of the first push tube and a retaining ring and a pawl ring placed at a front end of the guide pin, when the central sleeve is assembled, springs inside the central sleeve let every component in the hole of the central sleeve to move back and forth, then a seal sleeve screw to the second inner screw thread of a front end of the central sleeve to avoid every component in the central sleeve breaking away from the central sleeve, a hole placed in the middle of the seal sleeve passing through it, finally, screwing the first outer screw thread at a rear end of the central sleeve to the first inner screw thread at a front end of the lower sleeve to form the lower body; an upper body comprising a seal pipe having a third inner screw thread placed within, an upper sleeve, a push block and a second antenna, the upper sleeve having a second outer screw thread placed at a front end thereof, a step-like hole passing through the upper sleeve, then the second antenna being inserted into the hole and locked at the front end of the upper sleeve, the push block being placed inside the hole and placed in front of the second antenna, screwing the second outer screw thread of the upper sleeve to the third inner screw thread of the seal pipe to prevent the second antenna and the push block from separating apart and to form the upper body; a cone-like pawl suitably placed at a middle of the second antenna; the second antenna of the upper sleeve inserting through the hole of the central sleeve inside the lower body, when the pawl of the second antenna passing through the pawl ring, the upper sleeve and second antenna firmly got stuck in the central sleeve for an aperture of the pawl ring being smaller than that of the pawl of the second antenna, and held against a rear end of the seal sleeve from being pulled out.