Abstract: A platform system useful for constructing, maintaining, or repairing greenhouse roofs comprises a platform section providing a working area surface formed with removable treads supported on left and right platform rails. The platform section is supported by downwardly projecting upper and lower support bases appointed to rest on structural members of the roof, thereby providing a clearance between the working area surface and the roof beneath. Guardrails extend along the sides of the platform section between guardrail posts attached at the upper and lower ends of the platform rails. The system is light-weight, minimizing the loading imposed on the roof and permitting it to be readily positioned by a small work crew. The support base may include retractable rollers that permit it to be slid upward across the eaves and onto the roof. A deployment assist cart may be used to erect, support, and access the platform system.

Abstract: A method for producing a spliced yarn comprising alternating predetermined lengths of a first and a second yarn and to the yarn is disclosed. A predetermined length of a first yarn is drawn through an intermingling jet. A leading portion of a second yarn is forwarding into the intermingling jet and into overlapping relationship with a trailing portion of the first yarn. The yarns are held in the intermingling jet, as by a clamp disposed forwardly of the jet. Using a pressurized fluid the overlapped portions are intermingled. The first yarn is then severed, and the spliced portion and a predetermined length of the second yarn are drawn through the intermingling jet. The cycle is repeated with the second yarn being the currently drawn yarn and the first yarn being forwarded into overlapping relationship therewith.

Abstract: Apparatus for forming a spliced yarn includes a yarn conduction member with an intermingling jet disposed forwardly thereof. The yarn conduction member has respective yarn conduction channels through which the first and second yarns are conveyed to the intermingling jet. The yarn conduction member has a first and second knife blade disposed adjacent to one of the yarn conduction channels. The first and second knives are insertable into and retractable from the channel to which they are adjacent. In the inserted position the passage in the knife aligns with the channel into which it is inserted, while in the retracted position the solid portion of the blade interdicts the passage to prevent movement of a yarn therethrough.

Abstract: Apparatus for forming a spliced yarn includes a yarn conduction member with an intermingling jet disposed forwardly thereof. The yarn conduction member has respective yarn conduction channels through which the first and second yarns are conveyed to the intermingling jet. The axis of each yarn conduction channel from the inlet to the outlet of the member is a straight line, with no bends or deviations. The yarn conduction member has a knife blade disposed adjacent to a respective yarn conduction channel. Each knife blade has a passage defining a cutting edge and a solid portion disposed between the passage and the tip of the blade. The first and second knives are insertable into and retractable from the channel to which they are adjacent. In the inserted position the passage in the knife aligns with the channel into which it is inserted, while in the retracted position the solid portion of the blade interdicts the passage to prevent movement of a yarn therethrough.

Abstract: A method for producing a spliced yarn comprising alternating predetermined lengths of a first and a second yarn and to the yarn are disclosed.