Abstract In a continuous blow molding operation, mold release of the newly formed container is facilitated by providing a conveyor adjacent to the point where the mold opens. The newly formed container is connected at one end by waste material to a previously formed container that is in the conveyor and is connected at the other end to material in a closed mold behind the mold that is opening. The conveyor haul off speed and the speed of the molds are at a relative rate which maintains a certain tension in the waste material between the previously formed container and the newly formed container and there is also tension in the material between the two molds. This tension facilitates mold release of the newly formed container upon opening of the mold. The speed of the molds is greater than the haul off speed of the conveyor by a rate which is substantially equal to the rate of reduction of length in the material between the previously formed container and the closed mold to prevent any deformity in the containers due to an excess of tension.
The process as recited in claim 1 wherein said crystalline mono- Alpha -olefin is polypropylene.
Claim 2
Dependent Claim
20 words
The process as recited in claim 1 wherein said crystalline mono- Alpha -olefin is polypropylene and said containers are bottles.
Claim 3
Dependent Claim
40 words
The process as recited in claim 1 wherein only two molds are used whereby said one mold after opening, moves on a return stroke to clamp the oriented portion of the tubing between said heating means and said another mold.
Claim 4
Dependent Claim
251 words
A process for blow molding oriented containers comprising: providing an indefinite length of tubing comprising a solid polymer of crystalline mono- Alpha -olefin containing up to six carbon atoms, heating means, molds forward of said heating means, and a conveyor forward of said molds; said molds including a pair of molds one behind another; each of said molds having an oriented, expanded container therein; each container having a front seal line and a rear seal line; the container in one mold being connected at one end through waste material to a container on said conveyor and at the other end through waste material to the container in the other mold; the improvement comprising maintaining tension in the waste material located between said container on the conveyor and the forward seal line on said one mold and in the waste material between said pair of molds when both are closed whereby upon opening of said one mold the tension on the material will help dislodge the newly formed container from said one mold, and moving said molds toward said conveyor at a lineal speed which is faster than the lineal speed the conveyor is moving said container thereon by a rate substantially equal to the rate of reduction in length of the material between the forward seal lines of each of said molds to maintain tension in the material substantial enough to facilitate mold release but small enough to prevent deformity of any of the containers included in the material in tension.
Claim 5
Dependent Claim
15 words
The process as recited in claim 5 wherein said crystalline mono- Alpha -olefin is polypropylene.
Claim 6
Dependent Claim
20 words
The process as recited in claim 5 wherein said crystalline mono- Alpha -olefin is polypropylene and said containers are bottles.