| 摘要 |
PCT No. PCT/GB85/00333 Sec. 371 Date Apr. 21, 1986 Sec. 102(e) Date Apr. 21, 1986 PCT Filed Jul. 26, 1985 PCT Pub. No. WO86/01370 PCT Pub. Date Mar. 13, 1986.A metering mechanism comprises a housing (7) with a material inlet (12) and a rotary metering member (27) that is rotatably mounted between side walls (8,9) of the housing with its periphery exposed to a chamber (48) within the housing so as to meter material from the chamber as it rotates, characterized in that a removable insert (74) is provided that is a close fit in said chamber and has a passage (75) through it that communicates at one end with said inlet (12) and at the other end with the periphery of the rotary metering member (27) so that the effective volume of said chamber (48) is reduced to the volume of said passage (75). Thus, if the metering mechanism incorporates the known shutter-type tramlining device in which a shutter (24) serves to close the inlet (12) to the housing, the quantity of speed retained in the chamber within the housing is reduced and therefore the length of a bout that will be sown after closing the shutter will be correspondingly reduced. The metering mechanism may also incorporate a tramlining device comprising an arcuate shutter member (84) that is mounted within the housing so as to be rotatable about the rotary metering member between the periphery of the rotary metering member and the insert, thereby to open or close said other end of the passage (75) under the control of an external control mechanism (87). The arcuate shutter member (84) is carried on one side of an annular support member (35) that is rotatably mounted on a side wall (8, 37) of the housing and receives the adjacent end of the rotary metering member (27) as a close rotary and axially slideable fit. |
