Claims Analysis
Total Claims: 17
Claim 1
Independent Claim
213 words
A method for sealing together the ends of at least two different diameter tubes made of thermoplastic materials heat-sealable together to form a multiple-walled tube which comprises: (a) arranging the tubes concentrically with the ends to be sealed near each other, the end of one tube being positioned to extend beyond the end of the other tube; (b) positioning a rod having good heat conductivity and a higher melting point than the plastic of the tubes inside the inner tube with its one end spaced slightly axially inwardly of the end of said other tube to form an assembly of ends of said inner and outer tubes and rod; (c) placing said ends in a mold cavity having a surface conforming substantially to a desired outer surface of the sealed tube ends; and (d) heating said tube ends to a temperature sufficient to at least soften the plastic of the extended tube and seal the tube ends together, and shaping said plastic against the heat-conducting metal rod which facilitates conduction of heat through the sealing area and forms a dam to hold the maximum amount of melted plastic in the sealing area to make a strong joint and a multiple-walled tube is formed in which the ends of the tubes are sealed together.
Claim 2
Independent Claim
213 words
A method for sealing together the ends of at least two different diameter tubes made of thermoplastic materials heat-sealable together to form a multiple-walled tube which comprises: (a) arranging the tubes concentrically with the ends to be sealed near each other, the end of one tube being positioned to extend beyond the end of the other tube; (b) positioning a rod having good heat conductivity and a higher melting point than the plastic of the tubes inside the inner tube with its one end spaced slightly axially inwardly of the end of said other tube to form an assembly of ends of said inner and outer tubes and rod; (c) placing said ends in a mold cavity having a surface conforming substantially to a desired outer surface of the sealed tube ends; and (d) heating said tube ends to a temperature sufficient to at least soften the plastic of the extended tube and seal the tube ends together, and shaping said plastic against the heat-conducting metal rod which facilitates conduction of heat through the sealing area and forms a dam to hold the maximum amount of melted plastic in the sealing area to make a strong joint and a multiple-walled tube is formed in which the ends of the tubes are sealed together.
Claim 3
Dependent Claim
20 words
The method of claim 1 in which the sealing is conducted to form a tube having a completely closed end.
Claim 4
Dependent Claim
19 words
The method of claim 1 in which the tube ends are sealed by electrical high frequency heating said mold.
Claim 5
Dependent Claim
11 words
The method of claim 1 in which the rod is metal.
Claim 6
Dependent Claim
48 words
The method of claim 1 in which the tubes are made of thermoplastic materials having different melting points and the end of the tube made of the lower melting point plastic material extends slightly beyond the end of the other tube during the sealing of the tube ends.
Claim 7
Dependent Claim
21 words
The method of claim 5 in which the sealing is conducted to form a (double-walled) tube having a completely closed end.
Claim 8
Dependent Claim
18 words
The method of claim 1 in which the ends of the tubes are axially spaced apart during sealing.
Claim 9
Dependent Claim
37 words
The method of claim 7 in which the tubes are made of different melting point plastics and the end of the tube made of the lower melting point plastic extends beyond the end of the other tube.
Claim 10
Dependent Claim
99 words
The method as described in claim 1 for sealing together the ends of different diameter tubes to make a combination multiple-walled tube, the rod concentrically-positioned within said tubes having a circumferential shoulder near its end, the method further including the steps of: arranging the tubes and rod concentrically with the rod inside the inner tube and its shoulder near the sealing end area of the tube ends; and heating the assembly in the area of the tube ends to seal their edges together and form an internal shoulder in the sealing area corresponding to the shoulder of the rod.
Claim 11
Dependent Claim
24 words
The method of claim 9 in which the end of the rod adjacent its shoulder protrudes beyond the ends of the tubes during sealing.
Claim 12
Independent Claim
120 words
A method for completely sealing together the edges of at least two different diameter tubes made of thermoplastic material heat-sealable together to form a multiple-walled tube with a completely closed end which comprises: (a) arranging the tubes concentrically with the ends to be sealed near each other, one of said tubes being positioned to extend beyond the other; (b) placing the ends to be sealed in a mold cavity having a surface conforming substantially to the desired outer surface of the sealed tube ends; and (c) heating the ends of the assembled tubes and at least said extending tube end being heated sufficiently to seal the tube ends together to form a completely closed end and form a multiple-walled tube.
Claim 13
Independent Claim
120 words
A method for completely sealing together the edges of at least two different diameter tubes made of thermoplastic material heat-sealable together to form a multiple-walled tube with a completely closed end which comprises: (a) arranging the tubes concentrically with the ends to be sealed near each other, one of said tubes being positioned to extend beyond the other; (b) placing the ends to be sealed in a mold cavity having a surface conforming substantially to the desired outer surface of the sealed tube ends; and (c) heating the ends of the assembled tubes and at least said extending tube end being heated sufficiently to seal the tube ends together to form a completely closed end and form a multiple-walled tube.
Claim 14
Dependent Claim
24 words
The method of claim 11 in which the tubes are sealed by electrical high frequency heating and rapidly cooled after heating of the mold.
Claim 15
Dependent Claim
22 words
The method of claim 11 in which the tubes are arranged during sealing with the ends of the tubes axially spaced apart.
Claim 16
Dependent Claim
53 words
The method of claim 13 in which the tubes are made of plastics having different melting points, the tube of lower melting point plastic extends beyond the end of the other tube a distance of about its external diameter during heating, and the tube ends are sealed to form a completely sealed end.
Claim 17
Dependent Claim
14 words
The method of claim 13 in which the tube ends are completely sealed off.