US 5,188,046 AGranted

Plastic bobbin basket with damage resistant members

AssigneeBakron Corp.

InventorPaul Badillo

Life of this patent

Estimating the term…

Abstract

A bobbin basket for use with a rotary loop-taker in a lock-stitch sewing machine is disclosed. The basket is integrally formed of plastic, with damage resistant members for reducing wear and impact damage at specified locations. The extent of each such location may be only a small fraction of the potential area of wear and damage. Inserts are disclosed for the needle thread stop, the needle thread pick-up notch, the upstream side wall of a rotation-restraining notch, the bearing rib, and the downstream side wall of the rotation-restraining notch.

Claims29

Dependent claims

A bobbin basket for use with a rotary loop taker in a lock-stitch sewing machine, which basket comprises:

a cylindrical side wall, a crosswise support member for the cylindrical side wall extending across the bottom of the bobbin basket, a bobbin spool support post extending axially from said crosswise support member into the space defined by said cylindrical side wall,
a flange extending radially outward from the top portion of said cylindrical side wall, two portions of said flange forming first and second oppositely facing side walls that are positioned generally radially to form a rotation-restraining notch in the top surface of the flange, said first notch side wall forming the downstream side of the rotation-restraining notch relative to the direction of rotation of the rotary loop taker with which the bobbin basket is adapted to be used, said second notch side wall forming the upstream side of said notch relative to said direction of rotation, said notch being adapted to receive the stud portion of a stationary positioning finger with a secure but sufficiently loose fit to permit limited back-and-forth rotational movement of the bobbin basket, and
an annular bearing rib extending radially outward from said cylindrical side wall, said rib being located between the aforesaid outwardly extending flange and the bottom of the bobbin basket and extending substantially around the periphery of the bobbin basket except for a minor portion of said annular rib that is omitted to provide two oppositely facing rib end portions that define a needle thread pick-up and release area,
the first of said oppositely facing rib end portions forming a pick-up notch at the downstream end, relative to the aforesaid direction of rotation of the rotary loop taker with which the bobbin basket is adapted to be used, of the needle thread pick-up and release area, and
the second of said oppositely facing rib end portions being located adjacent said rotation-restraining notch to form a needle thread stop at the upstream end, relative to said direction of rotation, of the needle thread pick-up and release area,
characterized in that:
(a) the bobbin basket, including said cylindrical side wall, said outwardly extending flange and said outwardly extending bearing rib, is integrally formed of plastic,
(b) said bearing rib includes means for reducing wear on said second, upstream rib end portion that forms the aforesaid needle thread stop, as the needle thread loop comes into contact with said stop and the thread is pulled forcefully across the stop to tighten the loop around the bobbin thread,
(c) said bearing rib includes means for reducing wear on said first, downstream rib end portion that forms the aforesaid pick-up notch, as the needle thread loop is caught in said notch and moves axially across the notch as the rotary loop taker rotates and enlarges the loop,
(d) said second, upstream side wall of the rotation-restraining notch includes means for minimizing impact damage to said second side wall caused by the aforesaid stud portion of the stationary positioning finger as the bobbin basket is jerked back and forth by the needle thread loop to cause said second side wall to strike said stud repeatedly as tension is applied to the thread of the needle thread loop first in one direction and then in the other,
(e) said bearing rib includes means for reducing wear on the rib body caused by the rotary loop taker raceway in which the rib is journaled, while at the same time substantial contact is maintained between the raceway and the rib body including said wear-reducing means, and
(f) the area occupied by each of said means for reducing wear or minimizing impact damage at a given location on the bobbin basket falls in the range from a small fraction of the potential area of wear or impact damage at that given location to the entire area of potential wear or damage at that location.

9 more elements

A bobbin basket for use with a rotary loop taker in a lock-stitch sewing machine, which basket comprises:

a cylindrical side wall, a crosswise support member for the cylindrical side wall extending across the bottom of the bobbin basket, a bobbin spool support post extending axially from said crosswise support member into the space defined by said cylindrical side wall, and
a flange extending radially outward from the top portion of said cylindrical side wall, two portions of said flange forming first and second oppositely facing side walls that are positioned generally radially to form a rotation-restraining notch in the top surface of the flange,
an annular bearing rib extending radially outward from said cylindrical side wall and extending substantially around the periphery of the bobbin basket except for a minor portion of said annular rib that is omitted to provide two oppositely facing rib end portions that define a needle thread pick-up and release area,
one of said oppositely facing rib end portions being located adjacent said rotation-restraining notch to form a needle thread stop at the upstream end, relative to the direction of rotation of the rotary loop taker with which the bobbin basket is adapted to be used, of the needle thread pick-up and release area,
characterized in that:
(a) the bobbin basket, including said cylindrical side wall, said outwardly extending flange and said outwardly extending bearing rib, is integrally formed of plastic, and
(b) said bearing rib includes means for reducing wear on said rib end portion that forms the aforesaid needle thread stop at the upstream end of the needle thread pick-up and release area, as the needle thread loop comes into contact with said stop and the thread is pulled forcefully across the stop to tighten the loop around the bobbin thread,
the area occupied by said means for reducing wear on said needle thread stop falling in the range from a small fraction of the potential area of wear at that location to the entire area of potential wear at that location.

5 more elements

A bobbin basket for use with a rotary loop taker in a lock-stitch sewing machine, which basket comprises:

a cylindrical side wall, a crosswise support member for the cylindrical side wall extending across the bottom of the bobbin basket, a bobbin spool support post extending axially from said crosswise support member into the space defined by said cylindrical side wall, and
an annular bearing rib extending radially outward from said cylindrical side wall, a portion of said annular rib being omitted to provide two oppositely facing rib end portions that define a needle thread pick-up and release area,
one of said oppositely facing rib end portions forming a pick-up notch at the downstream end, relative to the direction of rotation of the rotary loop taker with which the bobbin basket is adapted to be used, of the needle thread pick-up and release area,
characterized in that:
(a) the bobbin basket, including said cylindrical side wall and said outwardly extending .bearing rib, is integrally formed of plastic, and
(b) said bearing rib includes means for reducing wear on said rib end portion that forms a pick-up notch, as the needle thread loop is caught in said notch and moves axially across the notch as the rotary loop taker rotates and enlarges the loop,
the area occupied by said means for reducing wear on said pick-up notch falling in the range from a small fraction of the potential area of wear at that location to the entire area of potential wear at that location.

4 more elements

A bobbin basket for use with a rotary loop taker in a lock-stitch sewing machine, which basket comprises:

a cylindrical side all, a crosswise support member for the cylindrical side wall extending across the bottom of the bobbin basket, and a bobbin spool support post extending axially from said crosswise support member into the space defined by said cylindrical side wall,
a flange extending radially outward from the top portion of said cylindrical side wall, two portions of said flange forming first and second oppositely facing side walls positioned generally radially to form a rotation-restraining notch in the top surface of the flange, said first notch side wall forming the downstream side of the rotation-restraining notch relative to the direction of rotation of the rotary loop taker with which the bobbin basket is adapted to be used, said second notch side wall forming the upstream side of said rotation-restraining notch relative to said direction of rotation, said notch being adapted to receive the stud portion of a stationary positioning finger with a secure but sufficiently loose fit to permit limited back and forth rotational movement of the bobbin basket,
characterized in that:
(a) the bobbin basket, including said cylindrical side wall and said outwardly extending flange, is integrally formed of plastic, and
(b) said second, upstream side wall of the rotation-restraining notch includes means for minimizing impact damage to said second side wall caused by the aforesaid stud portion of the stationary positioning finger as the bobbin basket is jerked back and forth by the needle thread loop to cause said second side wall to strike said stud repeatedly as tension is applied to the needle thread loop first in one direction and then in the other,
the area occupied by said means for minimizing impact damage to said second side wall falling in the range from a small fraction of the potential area of impact damage at that location to the entire area of potential wear at that location.

3 more elements

A bobbin basket for use with a rotary loop taker in a lock-stitch sewing machine, which basket comprises:

a cylindrical side wall, a crosswise support member for the cylindrical side wall extending across the bottom of the bobbin basket, and a bobbin spool support post extending axially from said crosswise support member into the space defined by said cylindrical side wall,
a flange extending radially outward from the top portion of said cylindrical side wall, two portions of said flange forming first and second oppositely facing side walls positioned generally radially to form a rotation-restraining notch in the top surface of the flange, said first notch side wall forming the downstream side of the rotation-restraining notch relative to the direction of rotation of the rotary loop taker with which the bobbin basket is adapted to be used, said second notch side wall forming the upstream side of said rotation-restraining notch relative to said direction of rotation, said notch being adapted to receive the stud portion of a stationary positioning finger with a secure but sufficiently loose fit to permit limited back and forth rotational movement of the bobbin basket,
characterized in that:
(a) the bobbin basket, including said cylindrical side wall and said outwardly extending flange, is integrally formed of plastic, and
(b) the portion of said flange that forms said first, downstream side wall of the rotation-restraining notch includes means for reducing wear on said flange portion caused by contact with the bobbin thread as it exits from the bobbin spool,
the area occupied by said means for reducing wear on said first side wall falling in the range from a small fraction of the potential area of wear at that location to the entire area of potential wear at that location.

3 more elements

Dependencies are inferred from the claim text.

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Abstract

A bobbin basket for use with a rotary loop taker in a lock-stitch sewing machine, which basket comprises:

a cylindrical side wall, a crosswise support member for the cylindrical side wall extending across the bottom of the bobbin basket, a bobbin spool support post extending axially from said crosswise support member into the space defined by said cylindrical side wall,
a flange extending radially outward from the top portion of said cylindrical side wall, two portions of said flange forming first and second oppositely facing side walls that are positioned generally radially to form a rotation-restraining notch in the top surface of the flange, said first notch side wall forming the downstream side of the rotation-restraining notch relative to the direction of rotation of the rotary loop taker with which the bobbin basket is adapted to be used, said second notch side wall forming the upstream side of said notch relative to said direction of rotation, said notch being adapted to receive the stud portion of a stationary positioning finger with a secure but sufficiently loose fit to permit limited back-and-forth rotational movement of the bobbin basket, and
an annular bearing rib extending radially outward from said cylindrical side wall, said rib being located between the aforesaid outwardly extending flange and the bottom of the bobbin basket and extending substantially around the periphery of the bobbin basket except for a minor portion of said annular rib that is omitted to provide two oppositely facing rib end portions that define a needle thread pick-up and release area,
the first of said oppositely facing rib end portions forming a pick-up notch at the downstream end, relative to the aforesaid direction of rotation of the rotary loop taker with which the bobbin basket is adapted to be used, of the needle thread pick-up and release area, and
the second of said oppositely facing rib end portions being located adjacent said rotation-restraining notch to form a needle thread stop at the upstream end, relative to said direction of rotation, of the needle thread pick-up and release area,
characterized in that:
(a) the bobbin basket, including said cylindrical side wall, said outwardly extending flange and said outwardly extending bearing rib, is integrally formed of plastic,
(b) said bearing rib includes means for reducing wear on said second, upstream rib end portion that forms the aforesaid needle thread stop, as the needle thread loop comes into contact with said stop and the thread is pulled forcefully across the stop to tighten the loop around the bobbin thread,
(c) said bearing rib includes means for reducing wear on said first, downstream rib end portion that forms the aforesaid pick-up notch, as the needle thread loop is caught in said notch and moves axially across the notch as the rotary loop taker rotates and enlarges the loop,
(d) said second, upstream side wall of the rotation-restraining notch includes means for minimizing impact damage to said second side wall caused by the aforesaid stud portion of the stationary positioning finger as the bobbin basket is jerked back and forth by the needle thread loop to cause said second side wall to strike said stud repeatedly as tension is applied to the thread of the needle thread loop first in one direction and then in the other,
(e) said bearing rib includes means for reducing wear on the rib body caused by the rotary loop taker raceway in which the rib is journaled, while at the same time substantial contact is maintained between the raceway and the rib body including said wear-reducing means, and
(f) the area occupied by each of said means for reducing wear or minimizing impact damage at a given location on the bobbin basket falls in the range from a small fraction of the potential area of wear or impact damage at that given location to the entire area of potential wear or damage at that location.

9 more elements