Blow molding machine

A method of controlling a blow molding machine during a period of time from completion of a predetermined number of a first product of a first resin to preparation of production of a second product of a second resin, the blow molding machine including a plurality of devices comprising an extruder, a transport jig, a calibrating unit, first mold, blow pin, die and core for the first product, and second mold, blow pin, and die and core for the second product, the method comprising the steps of:

• controlling a temperature of the first resin within the blow molding machine and a temperature of the second resin therewithin;
• controlling an operation of the plurality of devices, said operation controlling step ensuring a stop of the extruder after pressing out the first resin therein, a drainage of water within the first mold, a detaching of the first blow pin, a mounting of the transport jig, a detaching of the first mold by the transport jig, a detaching of the first die and core, a mounting of the second die and core, a mounting of the second mold, a detaching of the transport jig, a mounting of the second blow pin, a centering of the second blow pin, and a returning of the calibrating unit to a home position,
• said detaching of the first blow pin being carried out through a first block, a second block slidably engaged with said first block and having the first blow pin, and passages for supplying fluids to the first blow pin, said passages allowing a fluid communication between said first block and said second block in a stationary position of the two, said mounting of the second blow pin being carried out through said first block, said second block slidably engaged with said first block and having the second blow pin, and said passages for supplying said fluids to the second blow pin, said passages allowing a fluid communication between said first block and said second block in said stationary position of the two;
• controlling a sequent transport of some of the plurality of devices in predetermined positions, said some of the plurality of devices including the first mold, blow pin, and die and core, and the second mold, blow pin, and die and core;
• and
• controlling a change of the first resin for the second resin in accordance with a supply stop of the first resin and data on the second product.

A method of controlling a blow molding machine during a period of time from completion of a predetermined number of a first product of a first resin to preparation of production of a second product of a second resin, the blow molding machine including a plurality of devices comprising an extruder, a transport jig, a calibrating unit, first mold, blow pin, die and core for the first product, and second mold, blow pin, and die and core for the second product, the method comprising the steps of:

• controlling a temperature of the first resin within the blow molding machine and a temperature of the second resin therewithin;
• controlling an operation of the plurality of devices, said operation controlling step ensuring a stop of the extruder after pressing out the first resin therein, a drainage of water within the first mold, a detaching of the first blow pin, a mounting of the transport jig, a detaching of the first mold by the transport jig, a detaching of the first die and core, a mounting of the second die and core, a mounting of the second mold, a detaching of the transport jig, a mounting of the second blow pin, a centering of the second blow pin, and a returning of the calibrating unit to a home position,
• said centering of the second blow pin being carried out by:
• measuring predetermined variables of a fluid provided from at least four points which are opposite to each other in the diametrical direction of the second blow pin when the second blow pin is inserted into the second mold,
• comparing said predetermined variables with each other to obtain differences between every opposite two of said at least four points, and
• moving the second blow pin so that said differences of said predetermined variables are null;
• controlling a sequent transport of some of the plurality of devices in predetermined positions, said some of the plurality of devices including the first mold, blow pin, and die and core, and the second mold, blow pin, and die and core;
• and
• controlling a change of the first resin for the second resin in accordance with a supply stop of the first resin and data on the second product.

A method of controlling a blow molding machine during a period of time from completion of a predetermined number of a first product of a first resin to preparation of production of a second product of a second resin, the blow molding machine including a plurality of devices comprising an extruder, a transport jig, a calibrating unit, first mold, blow pin, die and core for the first product, and second mold, blow pin, and die and core for the second product, the method comprising the steps of:

• controlling a temperature of the first resin within the blow molding machine and a temperature of the second resin therewithin;
• controlling an operation of the plurality of devices, said operation controlling step ensuring a stop of the extruder after pressing out the first resin therein, a drainage of water within the first mold, a detaching of the first blow pin, a mounting of the transport jig, a detaching of the first mold by the transport jig, a detaching of the first die and core, a mounting of the second die and core, a mounting of the second mold, a detaching of the transport jig, a mounting of the second blow pin, a centering of the second blow pin, and a returning of the calibrating unit to a home position,
• said detaching of the first blow pin being carried out through a first block, a second block slidably engaged with said first block and having the first blow pin, and passages for supplying fluids to the first blow pin, said passages allowing a fluid communication between said first block and said second block in a stationary position of the two, said mounting of the second blow pin being carried out through said first block, said second block slidably engaged with said first block and having the second blow pin, and said passages for supplying said fluids to the second blow pin, said passages allowing a fluid communication between said first block and said second block in said stationary position of the two,
• said centering of the second blow pin being carried out by:
• measuring predetermined variables of a fluid provided from at least four points which are opposite to each other in the diametrical direction of the second blow pin when the second blow pin is inserted into the second mold,
• comparing said predetermined variables with each other to obtain differences between every opposite two of said at least four points, and
• moving the second blow pin so that said differences of said predetermined variables are null;
• controlling a sequent transport of some of the plurality of devices in predetermined positions, said some of the plurality of devices including the first mold, blow pin, and die and core, and the second mold, blow pin, and die and core;
• and
• controlling a change of the first resin for the second resin in accordance with a supply stop of the first resin and data on the second product.