Abstract: A selectively removable block and pusher assembly is provided for a feed chain comprising a plurality of links. At least some of the links are provided with a pair of parallel spaced pins extending transversely therefrom from which the block and pusher assembly is removable. Each block and pusher assembly comprises a block and a pusher removably attached to the block. The block includes a first pair of parallel, spaced bores extending therethrough parallel to its transverse axis for receiving the pins extending from the links, and a retaining member positioned in the block for releasably retaining circumferential grooves formed adjacent the free ends of the pins. The retaining member comprises a flexible and resilient U-shaped spring clip having a pair of spaced legs received in a second pair of spaced bores in the block and an intermediate portion which releasably retains the circumferential grooves in the pins.

Abstract: A bonded unitized envelope stack, manufacturing apparatus, and manufacturing method are provided in which envelopes in a stack are inter-connected by application of two spots of adhesive on the front panel of each envelope to engage the lower panel of the next above envelope. In one embodiment of the present invention, a conventional folding machine including a seal folder flap trap is modified to enable the application of the two spots of adhesive on the front panel of each envelope, and to produce bonded envelope stacks having a given fixed quantity of envelopes. When an envelope enters the seal folder flap trap, a photocell detects and triggers one counter of a dual counter system. A first counter increments each time an envelope enters the trap, until a count termed "preset 1" is reached. When "preset 1" is reached by the first counter, the glue applicator is deactivated. A second counter is then incremented.

Abstract: Method for forming an envelope having a tear strip or a tear-off flap portion for aiding in opening the envelope, comprising the steps of providing an envelope blank formed of a material capable of being weakened by the application of ultrasonic frequencies, forming the blank into a finished envelope, and applying ultrasonic energy to the finished envelope to form either a pair of closely-spaced, elongate distress lines or a single, straight distress line at which the fibers forming the material are weakened, thus defining a tear strip or a tear-off flap portion capable of manual separation form the remainder of the envelope. An envelope formed according to the above method comprises a body portion having a front panel, a back panel, and a seal flap extending outwardly from and formed integrally with a side of the front panel.