Abstract: A duct joiner for connecting an air duct to another duct or other part of an air conditioning system has a tubular neck portion, a retaining clip and a sealing ring both mounted on the neck portion. The retaining clip has a ring portion received in a groove in the outer surface of the neck portion and a series of resilient teeth extending outwardly from the ring portion. The teeth are resiliently deformable to allow a hollow duct to be fitted over the neck portion and have either sharp edges or barbs thereon which dig into the internal surface of the duct to retain the duct on the neck portion of the joiner. The sealing ring has a ring section received in another groove in the outer surface of the neck portion and a resilient skirt which provides a seal between the neck portion of the joiner and the duct. The joiner may have one or more other neck portions with respective retaining clips and sealing rings for joining one duct to one or more other ducts.

Abstract: An air diffuser for diffusing conditioned air into a room has a diffuser body mounted in a housing to define an air channel which narrows towards the outlet end of the housing to produce a venturi-like effect causing the air to speed up as it leaves the diffuser so that the conditioned air can penetrate stratified layers of air in the room. The diffuser body is of tapered form having a narrow upper end portion and a wider lower end portion disposed in the open, outlet end of the housing. The diffuser body has a surface which faces the internal surface of a sloping side wall of the housing and which is inclined at an angle to the vertical greater than that of the sloping side wall of the housing to provide the narrowing air channel. The diffuser body is adjustably mounted for movement relative to the housing so that the flow of conditioned air leaving the outlet end of the housing can be adjusted.

Abstract: A method for clipping a line segment boundary-defined area against a limiting plane is disclosed for use in a computer graphics display system wherein graphics figures are represented by random sets of polylines definitive of line segment boundary-defined areas. Pursuant to the clipping method, once two intersection points are generated against one plane, the points are connected to form an edge of the new clipped boundary-defined area. The order of intersection point connection is irrelevant to the invention and the method can accomodate discontinuously presented data as readily as continuously presented data. Implementing the method essentially requires only one register to store the first intersection point and a flag register to indicate the status of the present clip point, i.e., whether the clipped point is the first or second of two points to be paired.

Abstract: A multi-window display station having main frame (host) interactive and local personal computer display data buffers is provided. The outputs of the two data buffers are merged, using a row or swath buffer, according to default or escape codes stored in one of the data buffers and the combined output drives a plasma panel display. Registers for modified data tags and for presence/absence of escape codes speed the panel update process. Means are included to provide alpha-numeric and graphic windows together on the panel screen.

Abstract: A normally open plunger switch capable of closing upon initial movement of the plunger, and allows overtravel of the plunger at least to the extent of one half the depth of the switch. The actuator is pivoted in the case in the manner of a conventional rocker/actuator and it is coupled to the plunger by projecting portions on both it and on the plunger to provide for both these features.