Extendable paving screed

A method for providing a screed assembly for a paving machine, said screed assembly having an elongate main screed portion having a fixed length frame and an elongate extension screed portion longitudinally axially extendible from said main screed portion, said extension screed portion having a variable length frame defined by an inner end wall and an outer end wall and having an intermediate wall, said inner end wall and said intermediate wall being axially moveable one relative to the other;

• a coupling portion located between said variable length frame inner and outer end walls, said coupling portion having a first coupling member connected to said inner end wall and extending through said intermediate wall toward said outer end wall and a second coupling member connected to said outer end wall and extending to said intermediate wall, said first and second coupling members being coaxially slidable one within the other;
• and an actuator having a first end portion connected to said main screed portion frame and a second end portion connected to said extension screed portion variable length frame outer end wall, said actuator being adapted to controllably move said extension screed portion variable length frame longitudinally axially relative to said main screed portion fixed length frame between a fully retracted position and a fully extended position, comprising the steps of:
• moving said variable length portion intermediate wall toward said, inner end wall in response to said actuator moving said extension screed portion variable length frame longitudinally axially relative to said main screed portion fixed length frame to said fully retracted position, and
• moving said variable length portion intermediate wall away from said inner end wall in response to said actuator moving said extension screed portion variable length frame longitudinally axially relative to said main screed portion fixed length frame to said fully extended position.

A screed assembly for a paving machine, comprising:

• an elongate main screed portion having a fixed length frame;
• an elongate extension screed portion longitudinally axially extendible from said main screed portion, said extension screed portion having a variable length frame defined by an inner end wall and an outer end wall and having an intermediate wall, said inner end wall and said intermediate wall being axially moveable one relative to the other;
• a coupling portion located between said variable length frame inner and outer end walls, said coupling portion having a first cylindrical coupling member connected to said inner end wall and extending through said intermediate wall toward said outer end wall and a second cylindrical coupling member connected to said outer end wall and extending to said intermediate wall, said first and second cylindrical coupling members being coaxially slidable one within the other;
• an actuator having a first end portion connected to said main screed portion frame and a second end portion connected to said extension screed portion variable length frame outer end wall, said actuator being adapted to controllably move said extension screed portion variable length frame longitudinally axially relative to said main screed portion fixed length frame between a fully retracted position at which said variable length portion intermediate wall is urged toward said inner end wall and a fully extended position at which said variable length portion intermediate wall is urged away from said inner end wall, and
• wherein said cylindrical coupling members respectively include a key and keyway positioned to permit relative linear movement between said coupling members and to inhibit relative rotational movement between said coupling members.