Method and apparatus for making a series of pocketed coil springs
AssigneeSimmons U.S.A. Corporation
InventorWalter Stumpf
Life of this patent
Estimating the term…
Abstract
A method and apparatus are disclosed for making a series of coil springs pocketed within individual pockets in an elongate fabric strip comprised of two overlying plies capable of being thermally welded together. The fabric strip is fed along a guide path during which compressed coil springs are inserted between the piles with the axes of the springs substantially normal to the planes of the plies, whereafter the fabric plies are thermally welded together longitudinally and transversly to form a series of connected pocketed springs. After thermal welding, the pocketed springs are passed through a turner assembly during which the coil springs are reoriented within the fabric pockets to positions wherein the axes of the springs are transverse to the fabric strip.
Claims20
Apparatus for making a series of coil springs pocketed within an elongate stretchable fabric strip comprised of at least two overlying plies capable of being thermally welded together, said apparatus comprising, in combination, means defining a guide path adapted to receive said fabric strip for longitudinal movement therealong, indexing drive means operative to engage and to advance said fabric strip intermittently along said guide path, inserter means adjacent said guide path means and operative to deposit a compressed coil spring between said plies, first thermal weld head means operatively associated with said guide path means and operative to thermally weld said two plies together along at least one weld line longitudinally of said strip adjacent to the edge thereof into which the spring is inserted, second thermal weld head means operatively associated with said guide path means and adapted to thermally weld said two plies together along weld lines transversely of said strip between successive springs, said weld lines defining an individual spring retaining pocket about each of said inserted springs, both of said thermal weld head means being positioned adjacent to said inserter means along said guide path in the direction of movement of said fabric strip to hold the stretchable fabric strip during the insertion of spring between the plies, said first and second weld heads being disposed adjacent to each other and being operated simultaneously to complete the spring retaining pocket at a location immediately adjacent and downstream of said inserter means, means associated with said guide path to maintain said springs in compression between said two plies until after the operation of said weld head means, and control means operatively associated with said indexing drive means, said inserter means, and said first and second weld head means operable to effect operation of said inserter means and said weld head means in unison and in alternate relation with said indexing drive means so as to insert the springs and to form the pockets while said fabric strip is intermittently at rest.
Apparatus for making a series of coil springs pocketed within an elongate fabric strip comprised of at least two overlying plies capable of being thermally welded together, said apparatus comprising, in combination, means defining a guide path adapted to receive said fabric strip for longitudinal movement therealong, indexing drive means operative to engage and to advance said fabric strip intermittently along said guide path, inserter means adjacent said guide path means and operative to deposit a compressed coil spring between said plies, first thermal weld head means operatively associated with said guide path means and operative to thermally weld said two plies together along at least one weld line longitudinally of said strip adjacent to the edge thereof into which the spring is inserted, second thermal weld head means operatively associated with said guide path means and adapted to thermally weld said two plies together along weld lines transversely of said strip betwen successive springs, said weld lines defining an individual spring retaining pocket about each of said inserted springs, both of said thermal weld head means being positioned adjacnt to said inserter means along said guide path in the direction of movement of said fabric strip, means associated with said guide path to maintain said springs in compression between said two plies until after the operation of said first and second weld head means, control means operatively associated with said indexing drive means, said inserter means, and said first and second weld head means operable to effect operation of said inserter means and said weld head means in unison and in alternate relation with said indexing drive means so as to insert the springs and to form the pockets while said fabric strip is intermittently at rest, wherein said control means includes control circuit means operatively associated with said inserter means, said first and second thermal weld head means, and said indexing means and adapted to effect operation thereof in predetermined relation with each other during operation of said apparatus, said control circuit means including means for energizing said thermal weld head means, and further including safety switch means adapted to deenergize said thermal weld head means if said inserter means is prevented from fully inserting a coil spring between said fabric plies.
In apparatus for turning compressed coil springs disposed within individual pockets formed between overlying plies of a fabric strip so that the springs are reoriented from first positions wherein their coil axis are substantially perpendicular to the planes of said plies to second positions wherein their coil axis are substantially parallel to the planes of said plies said apparatus including guide path means adapted to receive and guide a length of said fabric strip having a series of pocketed springs therein, means associated with said guide path means and operative to intermittently advance said pocketed springs to a turning station, and turner means at said turning station operative to engage said fabric strip and effect turning of said springs from said first positions to said second positions;
- the combination therewith comprising spring positioning means operatively associated with said turner means and adapted to cramp said fabric strip toward one side of the guide path in opposition to the force exerted upon the strip by said turner means so that said springs expand into opposite ends of their respective pockets during turning thereof,
- said spring positioning means including a roller member supported for rotation about an axis substantially normal to the plane of said fabric strip in said guide path at one side of center thereof as said strip approaches said turning station, said roller member being positioned to engage said strip in a manner to urge said fabric strip with contained springs toward the side of the guide path opposite said roller.
A method for making a series of connected pocketed coil springs comprising the steps of intermittently advancing two overlying plies of thermally weldable fabric strip along a predetermined guide path, successively inserting a plurality of compressed coil springs between said two overlying plies of thermally weldable fabric strip when said strip is at rest so that said springs are spaced longitudinally along said strip, maintaining the compression of said springs and thermally welding said fabric plies together with contact pressure simultaneously along weld lines transversely of said strip between successive inserted springs and longitudinally of said strip along the edge thereof into which the springs are inserted when said strip is at rest so as to form a retaining pocket about each of said springs while the springs are compressed and at a location immediately adjacent to and downstream of the insertion of the compressed spring between the plies, said contact pressure holding said edge in place at a location downstream in the advancing direction and closely adjacent to the path of movement of the compressed spring during its insertion.
Apparatus for making a series of coil springs pocketed within an elongate fabric strip comprised of at least two overlying plies capable of being thermally welded together, said apparatus comprising, in combination, means defining a guide path adapted to receive said fabric strip for longitudinal movement therealong, indexing drive means operative to engage and to advance said fabric strip intermittently along said guide path, inserter means adjacent said guide path means and operative to deposit a compressed coil between said plies, first thermal weld head means operatively associated with said guide path means and operative to thermally weld said two plies together along at least one weld line longitudinally of said strip adjacent to the edge thereof into which the spring is inserted, second thermal weld head means operatively associated with said guide path means and adapted to thermally weld said two plies together along weld lines transversely of said strip between successive springs, said weld lines defining an individual spring retaining pocket about each of said inserted springs, both said thermal weld head means being positioned adjacent to said inserter means along said guide path in the direction of movement of said fabric strip, means associated with said guide path to maintain said springs in compression between said two plies until after the operation of said weld head means, and control means operatively associated with said indexing drive means, said inserter means, and said first and second weld head means operable to effect operation of said inserter means and said weld head means in unison and in alternate relation with said indexing drive means so as to insert the springs and to form the pockets while said fabric strip is intermittently at rest, and
- a continuously rotating beater which flails the fabric strip transversely thereof after the pockets have been formed about the springs and the springs have been released for expansion within their pockets, said beater serving to turn the springs within the pockets to position their axis transversely of the strip to expand into the opposite ends of said pockets, and upstanding roller positioned to contact the fabric along one side edge thereof before the strip enters the zone of the beater to cramp the strip toward the opposite side of the guide path in opposition to the force exerted on the strip by the beater.
Dependencies are inferred from the claim text.