Abstract: A multiple-document detection system for an insertion machine comprises a plurality of document detectors, each detector being preset to a successive maximum allowable document-group-thickness measurement; a group of documents whose measured thickness exceeds the preset maximum allowable size for a particular detector will cause that detector's input line to change from a "normal" level to a "tripped" level. A processing means then determines the actual number of documents in a measured group of documents according to which of the successively preset detectors was the first to be "tripped". The processing means also receives a signal indicative of an expected number of documents for the particular measured group. The expected-number signal is sent, for example, by a reader, upstream of the plurality of detectors, which reads the expected number from a master document in the group.

Abstract: In a document insertion machine, third-party advertising documents are fed from downstream insert stations (36, 37, 38, 39). The third party insert stations include an optional insert station (39) from which documents are to be fed only if the additional weight occasioned by the feeding does not cause an increase in the postage for a customer's stuffed envelope. The other third party insert stations (36, 37, 38) are chargeback stations which feed documents regardless of the impact of feeding upon the weight of a customer's stuffed envelope. The insertion machine apportions, among the chargeback stations (36, 37, 38), any increase in postage cost which occurs when the feeding of documents from the chargeback stations causes a customer's stuffed envelope to be classified in a more expensive postage category.

Abstract: An electrical circuit provides an indication of the relative positioning of a sensor with respect to sensed indicia borne by documents traveling proximate the sensor. The circuit includes a first clock (10), a sensor switching circuit (30) which determines when the indicia is sensed, and means for determining whether the indicia is read at an acceptable time between successive first clock (10) pulses in order for the sensor to be properly positioned with respect to a document.