| 摘要 |
<p>of the Invention The motor drives the timing drum continuously at low speed through a gear train having a one-way clutch. The motor also drives the input of a second one-way clutch having a drive on its output engageable with the spaced teeth on the interrupted gear formed on the hub of the drum. When the low speed drive rotates the drum to a position in which a tooth on the hub can be engaged by the drive gear the drum is rapidly advanced until contact with the tooth is lost. Switches operated by the cams on the drum are sequenced rapidly during rapid advance. When the drum is manually advanced both clutches are overridden.</p> |
