US 4,503,976 A · Envelope tracking system for mail sorting machines

Abstract

An improved envelope tracking and control system for a mail sorting machine of the type which reads a sorting code imprinted on each envelope and deposits the envelope in the proper sorting bin by deflecting a diverter gate associated with the bin. Each diverter mechanism has two sets of photo sensors which sense the presence of an approaching envelope. Tracking circuitry processes the sort code obtained from the envelope and transfers the processed data to the tracking circuit for the next diverter if the data does not coincide with a code that has been preassigned to the diverter. The processed data is held in a latch circuit and is passed on only if the envelope is sensed by the second set of photo sensors. If there is coincidence of the data, a one shot pulse applied to a solenoid deflects the appropriate gate for a predetermined time period that avoids possible damage to the solenoid or to the circuit components. Existing components are used in a self test system which includes an astable oscillator that simulates successive envelopes passing through the machine.

Claims10

Dependent claims

In a mail sorting machine having a conveyor for transporting envelopes along an envelope path, a plurality of gates for diverting the envelopes off of said path control circuitry for comparing data indicative of each envelope with preassigned data corresponding to each gate approached by the envelope, means for controlling each gate in a manner to divert an envelope off of said path in the event of coincidence between the data indicative of the envelope and data corresponding to the gate, a clock controlled circuit included in said control circuitry for initiating same, and sensing means for normally applying a clock pulse to said clock controlled circuit upon approach of an envelope toward a gate, the improvement comprising:

first switch means for disabling said sensing means in a test position, said first switch means having a normal position wherein the sensing means is enabled;
an astable oscillator for applying test clock pulses to said clock controlled circuit in a test mode of operation to simulate envelopes successively approaching the gates;
and
second switch means having a normal position disconnecting said oscillator from the clock controlled circuit and a test position connecting said oscillator with the clock controlled circuit to apply test clock pulses thereto in the test mode,
whereby in the normal position of said first and second switch means said clock controlled circuit is clocked by envelopes successively approaching the gates and in the test position of said first and second switch means said oscillator applies to the clock controlled circuit test clock pulses simulating envelopes successively approaching the gates.

2 more elements

In a mail sorting machine having a conveyor for transporting envelopes along an envelope path and a plurality of serially arranged diverters for diverting envelopes off of said path, the improvement comprising:

first sensing means for each diverter located upstream of the diverter and operable to sense the presence of an envelope approaching the diverter;
means for providing a first alert signal in response to sensing of an approaching envelope;
circuit means for each diverter responsive to said first alert signal and operable to process data indicative of the approaching envelope and to compare the processed data with preassigned data corresponding to the diverter being approached by the envelope;
a latch circuit for receiving the processed data from said circuit means and holding the processed data, said latch circuit having a clock input and responding to the application of a signal to said clock input by transferring the processed data from the latch circuit to the circuit means for the next diverter approached by the envelope;
second sensing means for each diverter located downstream from said first sensing means and operable to sense an envelope present at said second sensing means;
means for applying a second alert signal to said clock input of the latch circuit when an envelope is sensed at said second sensing means;
and
control means for each diverter for controlling same in a manner to divert each approaching envelope off of said envelope path in the event of coincidence between the processed data and the preassigned data corresponding to the diverter.

5 more elements

Dependencies are inferred from the claim text.

Envelope tracking system for mail sorting machines

Life of this patent

Envelope tracking system for mail sorting machines

Life of this patent

Abstract

Claims10