Claims
- 1. A method for forming a sleeve about an elongated folding blade having four spaced fold lines, said blade having at least three heaters adjacent respective corners thereof, comprising:
- (a) disposing a sheet of thermoplastics material upon a support table including an elongated anvil member and two rotatable fold plates speced apart on opposite sides of said anvil member;
- (b) engaging said thermoplastics sheet material between said anvil member and an elongated first heater characterized by two spaced corners;
- (c) heating said sheet material with said first heater while said material is engaged between said first heater and said anvil member;
- (d) bending the heated said sheet material about said spaced corners by rotating said fold plates, forming said material, about said first heater, into a channel having two sides;
- (e) heating said sides locally along two regions spaced from said first heater by two additional heaters of said three heaters;
- (f) bending upper portions of each of said sides about corners defined by said two heaters thereby forming said sleeve.
- 2. The method of claim 1 including engaging said sheet material between said anvil and said blade approximately midway between ends of said sheet material.
- 3. The method of claim 1 including cooling said sleeve and removing said sleeve from said blade.
- 4. The method of claim 1 wherein each of said two additional heaters contact said material spaced from ends of said material so that bends about said additional heaters define a side and said sleeve.
- 5. The method of claim 4 including forming said material spaced from said ends so as to define said side with end portions of said material overlapped.
Parent Case Info
This is a continuation of application Ser. No. 726,263, filed Sept. 24, 1976 now abandoned, which is a division of prior application Ser. No. 535,980, filed Dec. 23, 1974, now U.S. Pat. No. 4,002,417.
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Divisions (1)
|
Number |
Date |
Country |
Parent |
535980 |
Dec 1974 |
|
Continuations (1)
|
Number |
Date |
Country |
Parent |
726263 |
Sep 1976 |
|