| 摘要 |
<p>The disclosure herein describes a device for collecting sap from trees which has a sap-collecting section adapted to be inserted into the outer layers of a tree; this section displays thereon an annular recess in which is received an expansible sealing element. A second member is partially mounted over the sapcollecting section of the first member and is adapted to be moved against the sealing element so as to expand the element when the device is inserted into a tree cavity to thereby prevent air infiltration in the device when the sap-collecting system is operating under vacuum conditions.</p> |
