Furnace for the heat treatment of work pieces

A furnace for the heat treatment of work pieces, comprising:

• a heat treatment chamber defined by several furnace walls and having a central vertical axis;
• conveyor means having a first group of work piece support elements substantially arranged in a first generally helical array concentric with said vertical axis and a second group of support elements arranged concentrically outside said first group, said first and second groups together defining a helical transport path inside said heat treatment chamber extending concentrically relative to and radially spaced from said vertical axis;
• means for moving one of said first and second groups axially and rotatably relative to the other of said first and second groups for lifting work pieces from the support elements of the other group onto the support elements of the one group, rotating and lowering the lifting work pieces onto respectively adjacent support elements of the other group;
• means for holding the other of said groups stationary within said heat treatment chamber;
• one of said mounting means including axially spaced apart annular members, axially extending support bars respectively mounted at opposite ends on said annular members, axially movable tubular mountings between each of said first group of support elements and said support bars, and tubular spacers between axially adjacent ones of said first group of support elements for determining the axial spacing of the support elements from each other to adjust the furnace for different height work pieces.

A furnace for heating workpieces, comprising:

• a furnace chamber having a vertical central axis;
• means for charging and discharging workpieces to and from said furnace chamber;
• conveyor means arranged substantially concentrically with respect to said axis;
• said conveyor means comprising a first group of workpiece support elements and a second group of workpiece support elements arranged helically about said axis for conveying the workpieces within at least a portion of said furnace chamber from said charging means to said discharging means;
• inner mounting means extending between top and bottom portions of said furnace chamber and outer mounting means extending between top and bottom portions of said furnace chamber;
• said support elements of said first group being mounted on said inner mounting means along the inner portion of said conveyor means and projecting substantially radially outwardly toward said outer mounting means, and said support elements of said second group being mounted to said outer mounting means along the outer portion of said conveyor means and projecting substantially radially inwardly toward said inner mounting means.
• said inner mounting means and said first group of support elements being movable relative to said outer mounting means and said second group of support elements in substantially vertical directions parallel to said axis and in substantially circular directions concentric to said axis such that said relative movement provides step-wise travel of the workpieces in a helical direction of travel concentric with said axis, the workpieces being supported alternatively by said first and said second group of support elements at alternating points of engagement;
• shaft means extending into said furnace chamber coaxially with said central axis for being driven externally of said furnace chamber axially and rotationally;
• one of said mounting means being drivingly and fixedly connected on said shaft for axial and rotational movement with said shaft for conveying;
• bearing means mounting the other of said mounting means on said shaft for axial and rotational relative movement for conveying, and for accurately locating said first and second groups of support elements relative to each other throughout the conveying;
• and
• means holding said other of said mounting means stationary.

A furnace for heating workpieces, comprising:

• a furnace chamber having a vertical central axis;
• means for charging and discharging workpieces to and from said furnace chamber;
• conveyor means arranged substantially concentrically with respect to said axis;
• said conveyor means comprising a first group of workpiece support elements and a second group of workpiece support elements arranged helically about said axis for conveying the workpieces within at least a portion of said furnace chamber from said charging means to said discharging means;
• inner mounting means extending between top and bottom portions of said furnace chamber and outer mounting means extending between top and bottom portions of said furnace chamber;
• said support elements of said first group being mounted on said inner mounting means along the inner portion of said conveyor means and projecting substantially radially outwardly toward said outer mounting means, and said support elements of said second group being mounted to said outer mounting means along the outer portion of said conveyor means and projecting substantially radially inwardly toward said inner mounting means;
• said inner mounting means and said first group of support elements being movable relative to said outer mounting means and said second group of support elements in substantially vertical directions parallel to said axis and in substantially circular directions concentric to said axis such that said relative movement provides step-wise travel of the workpieces in a helical direction of travel concentric with said axis, the workpieces being supported alternatively by said first and said second group of support elements at alternating points of engagement;
• shaft means extending into said furnace chamber coaxially with said central axis for being device externally of said furnace chamber axially and rotationally;
• one of said mounting means being drivingly and fixedly connected on said shaft for axial and rotational movement with said shaft;
• means holding the other of said mounting means stationary within said furnace chamber;
• said one mounting means including a plurality of circumferentially arranged bars parallel to said axis and rigidly connected to said shaft, the support elements of said one mounting means being non-rotatably and telescopically mounted on respective one of said bars, with each bar having a plurality of vertically spaced support elements telescopically mounted on it;
• and
• spacer means telescopically mounted on said bars between vertically adjacent support elements for adjusting the vertical spacing between support elements to thereby accommodate different sized workpieces.