초록 ▼

A container is made in two stages from material such as thermoplastics that is deformable when heated. In the first stage a preform (1) is injection moulded, the mould parts easily releasing a tubular body (2) with a closed end and an outwardly projecting rim (3) at the open end. On or in the surfac

A container is made in two stages from material such as thermoplastics that is deformable when heated. In the first stage a preform (1) is injection moulded, the mould parts easily releasing a tubular body (2) with a closed end and an outwardly projecting rim (3) at the open end. On or in the surface of the rim facing away from the body there is a formation such as a spiral rib (5) or groove. In the second stage the still heated preform (1) is blow moulded, possibly with some preliminary mechanical stretching, with the blow pin (9) seated in the open end of the body (2) and the preform held by the outer part (7) of its rim. The wall of the body (2) is expanded and the inner part (4) of the rim is urged away from the blow pin (9), deforming into a short tubular mouth with the formation (5) facing inwards. A spiral becomes a screw thread for receiving a screw-in cover.

대표청구항 ▼

1. A method of making a container to which entry is via an opening having a detent (5) for positively retaining a closure member within that opening, the material of the container being susceptible to deformation when heated, characterised in that in a first stage an embryo container (1) is formed a

1. A method of making a container to which entry is via an opening having a detent (5) for positively retaining a closure member within that opening, the material of the container being susceptible to deformation when heated, characterised in that in a first stage an embryo container (1) is formed as a closed end tube (2) with an outward, generally radial flange (4, 7) at its mouth, part of the upper surface of which flange is to provide the inside of the opening, the detent (5) being simultaneously formed as a projection from or depression in said surface, and in that in a second stage the outer peripheral portion (7) of the flange is held fast while the tube (2), at an elevated temperature, is expanded by differential pressure, this drawing down and forcing outwardly the inner portion (4) of the flange and transforming said upper surface from an upwardly facing one into a passage providing the opening with the detent (5).