Machine for forming cavities in foam pads and trimming same

Claim 2

A machine comprising a die in the form of a flat rigid plate material including a surface section for supporting a foam blank or pad and an aperture exposing a selected area portion of the lower surface of a foam pad supported on the die, a pressure plate superimposed above the die, means to advance the pressure plate against the upper surface of the foam pad whereby to extrude a fraction of the foam material through the aperture to the extent of forming a mound of the foam below the die but with a fraction of the total thickness of the foam within the outline of the aperture remaining above the die, a horizontal knife below the die and contiguous thereto, means for traversing the knife across the foam material to sever the mound, whereby a cavity in the undersurface of the pad results upon removal of the pressure and return of the foam material to its original expanded condition, and a vertical knife adapted to cut through the blank or pad to form an end thereof, and means to advance the vertical knife through the blank or pad.

Claim 3

A machine as defined in claim 1 in which there are means mounting the vertical knife which are adjustable to effect either a vertical or angular cut.

Claim 4

A machine comprising a stationary die in the form of a rigid plate presenting an elongated flat smooth surface section adapted to support a foam blank or pad for longitudinal sliding advancement over the plate or stationary lodgment thereon, and an aperture in the flat surface section adapted to expose a predetermined area portion of the lower surface of a foam pad supported on the die, a pressure plate superimposed above the die presenting a surface section having a substantially flat area greater than that of the aperture and overlying the latter with portions extending laterally beyond the perimeter of the aperture, means to force the pressure plate from an elevated position to a lowered position whereby its surface section is pressed down against the upper surface of the foam pad compressing and clamping the latter on the stationary die plate outside the perimeter of the aperture, and extruding a fraction of the foam material through the aperture to the extent of forming a mound of the foam below the die but with a fraction of the total thickness of the foam within the outline of the aperture remaining above the die, a longitudinally shiftable horizontal knife disposed below the die and contiguous thereto, and means for advancing and retracting the knife whereby in advancing it traverses the extruded foam material to sever the mound resulting in the formation of a cavity in the undersurface of the pad upon removal of the pressure, the space above the die when the pressure plate is in elevated position being free of obstruction for a sufficient height to permit unimpeded movement over the die of foam to be worked on.

Claim 5

A machine comprising a stationary die in the form of a rigid plate presenting an elongated flat smooth surface section adapted to support a foam blank or pad for longitudinal sliding advancement over the plate or stationary lodgment thereon, and an aperture in the flat surface section adapted to expose a predetermined area portion of the lower surface of a foam pad supported on the die, a pressure plate superimposed above the die presenting a surface section having a substantially flat area greater than that of the aperture and overlying the latter with portions extending laterally beyond the perimeter of the aperture, means to force the pressure plate from an elevated position to a lowered position whereby its surface section is pressed down against the upper surface of the foam pad compressing and clamping the latter on the stationary die plate outside the perimeter of the aperture, and extruding a fraction of the foam material through the aperture to the extent of forming a mound of the foam below the die but with a fraction of the total thickness of the foam within the outline of the aperture remaining above the die, a longitudinally shiftable horizontal knife disposed below the die and contiguous thereto, and means for advancing and retracting the knife whereby in advancing it traverses the extruded foam material to sever the mound resulting in the formation of a cavity in the undersurface of the pad upon removal of the pressure, the space above the die when the pressure plate is in elevated position being free of obstruction for a sufficient height to permit unimpeded movement over the die of foam to be worked on.

Claim 6

A machine as defined in claim 3 in which the die is of a width sufficient to handle two foam blanks or pads simultaneously and there are two apertures in the die transversely separated, a longitudinal guide is positioned between the apertures to define separate channels for receiving the pads, and there are pressure plates superimposed above the die for coaction with both pads, the last named pressure plates being interconnected for simultaneous movement.

Claim 7

A machine as defined in claim 1 in which there are two vertical knives spaced horizontally apart to form both ends of the pad, and means independently mounting the knives which are adjustable to change the distance between them and to effect either a vertical or angular cut.

Claim 8

A machine as defined in claim 3 in which there is an elongated frame, the die is mounted stationary in the frame, the knife is an elongated blade type, means supported by the frame mount the knife at both ends thereof for longitudinal movement relative to the frame, the means for traversing the knife across the foam include a traversing screw and a travelling nut thereon, and means transmitting travel of the nut to the knife.

Claim 9

A machine as defined in claim 3 in which there is an elongated frame, the means to advance the pressure plate includes a cross beam on which the pressure plate is mounted, vertically movable stabilizing means carried on sections of the frame support opposite ends of the cross beam, and a fluid pressure system is coupled to the cross beam to lower and raise the beam and consequently the pressure plate.

Claim 10

A machine as defined in claim 1 in which there are means mounting the vertical knife which include a fixed standard, a plate slidable on the standard, means connecting such knife to the standard, and the means to advance such knife comprise bell crank assemblies.

Claim 11

A machine as defined in claim 1 in which both horizontal and vertical knives are reciprocable, and a reciprocating means is connected to each knife.

Claim 12

A machine as defined in claim 1 which includes a back pressure plate subjacent the bottom of the die, the back pressure plate presenting a flat surface section having an area at least as great as that of the aperture and in general vertical alignment therewith, and means to force the last named plate from a lowered position to an elevated position in pressure contact with the foam mound to increase the density thereof throughout the mound during the cutting action of the knife.

Claim 13

A machine comprising a stationary die in the form of a rigid plate presenting an elongated flat smooth surface section adapted to support a foam blank or pad for longitudinal sliding advancement over the plate or stationary lodgment thereon, and an aperture in the flat surface section adapted to expose a predetermined area portion of the lower surface of a foam pad supported on the die, a pressure plate superimposed above the die presenting a surface section having an area approximately as great as that of the aperture and in general vertical alignment therewith, means to force the pressure plate from an elevated position to a lowered position whereby its surface section is pressed down against the upper surface of the foam pad to extrude a fraction of the foam material through the aperture to the extent of forming a mound of the foam below the die but with a fraction of the total thickness of the foam within the outline of the aperture remaining above tHe die, a longitudinally shiftable horizontal knife disposed below the die and contiguous thereto, means for advancing and retracting the knife whereby in advancing it traverses the extruded foam material to sever the mound resulting in the formation of a cavity in the undersurface of the pad upon removal of the pressure, the space above the die when the pressure plate is in elevated position being free of obstruction for a sufficient height to permit unimpeded movement over the die of foam to be worked on, a back pressure plate subjacent the bottom of the die, the back pressure plate presenting a flat surface section having an area at least as great as that of the aperture and in general vertical alignment therewith, and means to force the last named plate from a lowered position to an elevated position in pressure contact with the foam mound to increase the density thereof throughout the mound during the cutting action of the knife.

Claim 14

A machine comprising a stationary die in the form of a rigid plate presenting an elongated flat smooth surface section adapted to support a foam blank or pad for longitudinal sliding advancement over the plate or stationary lodgment thereon, and an aperture in the flat surface section adapted to expose a predetermined area portion of the lower surface of a foam pad supported on the die, a pressure plate superimposed above the die presenting a surface section having an area approximately as great as that of the aperture and in general vertical alignment therewith, means to force the pressure plate from an elevated position to a lowered position whereby its surface section is pressed down against the upper surface of the foam pad to extrude a fraction of the foam material through the aperture to the extent of forming a mound of the foam below the die but with a fraction of the total thickness of the foam within the outline of the aperture remaining above tHe die, a longitudinally shiftable horizontal knife disposed below the die and contiguous thereto, means for advancing and retracting the knife whereby in advancing it traverses the extruded foam material to sever the mound resulting in the formation of a cavity in the undersurface of the pad upon removal of the pressure, the space above the die when the pressure plate is in elevated position being free of obstruction for a sufficient height to permit unimpeded movement over the die of foam to be worked on, a back pressure plate subjacent the bottom of the die, the back pressure plate presenting a flat surface section having an area at least as great as that of the aperture and in general vertical alignment therewith, and means to force the last named plate from a lowered position to an elevated position in pressure contact with the foam mound to increase the density thereof throughout the mound during the cutting action of the knife.

Claim 15

A machine as defined in claim 11 in which the die is of a width sufficient to handle two foam blanks or pads simultaneously and there are apertures in the die transversely separated, a longitudinal guide is positioned between the transversely separated apertures to define separate channels for receiving the pads, pressure plates are superimposed above the die for coaction with both pads, and back pressure plates are disposed subjacent the bottom of the die, each back pressure plate being in general vertical alignment with an aperture above it and presenting a flat surface section having an area at least as great as that of the aperture with which it is aligned, and means to force each back pressure plate from a lowered position to an elevated position in pressure contact with the foam mound directly above it to increase the density thereof throughout the mound during the cutting action of the knife.