Preform conveying device, preform conveying method, and blow molding device

Patent metadata

Field	Value
Publication number	US-11065803-B2
Application number	US-201515513863-A
Country	US
Kind code	B2
Filing date	Sep 17, 2015
Priority date	Sep 24, 2014
Publication date	Jul 20, 2021
Grant date	Jul 20, 2021

Abstract

A preform conveying device ( 100 ) of the invention includes a control unit that detects an arriving time at which a conveyor jig arrives at a reference position based on an output of a first encoder, and commands a second motor to move a conveyor arm to a target position at regular intervals from the arriving time. The target position in each command is a position obtained by adding, to a current position of the conveyor jig which is obtained based on a latest output of the first encoder which was obtained when the command has been issued, a moving distance by which the conveyor jig has advanced during a delay time T which spans from a time when the latest output is outputted from the first encoder to a time when the command is received by the second motor.

First claim

The invention claimed is:

1. A preform conveying device, comprising:
a continuous conveyor section that continuously conveys a conveyor jig which supports a preform along a heating conveyor path;
an intermittent conveyor section that intermittently conveys a conveyor arm between a first position and a second position along a direction which is parallel to the heating conveyor path, the preform being transferred from the conveyor jig to the conveyor arm during the conveying of the conveyor arm; and
a controller that controls the intermittent conveyor section so that the conveyor arm which was waiting in the first position can catch up with the conveyor jig, which is being conveyed continuously,
wherein the continuous conveyor section includes a first motor which applies conveying force to the conveyor jig and a first encoder which detects a rotation angle of the first motor,
wherein the intermittent conveyor section includes a second motor which applies conveying force to the conveyor arm,
wherein the controller is in communication with the first and second encoders and detects an arriving time at which the conveyor jig arrives at a reference position facing the first position based on an output of the first encoder, and commands the second motor to move the conveyor arm to a target position at regular intervals from the arriving time, the target position in each command being a position calculated by the controller by adding, to a current position of the conveyor jig which is obtained based on a latest output of the first encoder which was obtained when the command has been issued, a moving distance by which the conveyor jig has advanced during a delay time which spans from a time when the latest output is outputted from the first encoder to a time when the command is received by the second motor,
wherein the continuous conveyor section further includes:
an endless chain conveying the conveyor jig and in which a plurality of links are connected; and
a drive sprocket driven by the first motor and meshing with the endless chain, and

wherein a distance over which the endless chain moves from the reference position during a synchronously driving period, which is a period during which the conveyor arm staying in the first position is caused to catch up with the conveyor jig by the command, is set less than one fourth of a link length which is a length between supporting points of one link.

2. The preform conveying device according to claim 1 ,
wherein the controller calculates the moving distance by multiplying a constant time corresponding to the delay time by a speed of the conveyor jig.

3. The preform conveying device according to claim 1 ,
wherein the controller calculates the moving distance based on an average speed of the endless chain during the synchronously driving period.

4. The preform conveying device according to claim 3 ,
wherein the conveyor jig includes a conveying table which is capable of moving up and down and which supports the preform in an inverted state where a mouth portion of the preform is facing downwards,
wherein the intermittent conveyor section includes a forward-backward drive portion which drives the conveyor arm to move forward and backward with respect to the conveying table, and
wherein a timing at which the synchronously driving period ends is set to be after the conveyor arm has been moved forward by the forward-backward drive portion to hold the mouth portion of the preform and when the conveying table is lowered.

5. The preform conveying device according to claim 4 ,
wherein the controller controls the intermittent conveyor section during an additional synchronously driving period which is a period from after the end of the synchronously driving period to when the conveyor arm is moved backward by the forward-backward drive portion, the moving distance in a command outputted from the controller during the additional synchronously driving period being calculated based on the average speed of the endless chain during the synchronously driving period.

6. The preform conveying device according to claim 1 ,
wherein the intermittent conveyor section further includes a second encoder for that detects a rotational angle of the second motor; and
wherein the controller starts a transfer operation of transferring the preform from the conveyor jig to the conveyor arm when a distance between a position of the transfer jig which is obtained based on a latest output from the first encoder and a position of the conveyor arm which is obtained based on a latest output from the second encoder becomes a predetermined value or smaller.

7. A blow molding device comprising:
the preform conveying device according to claim 1 .

8. A preform conveying method comprising:
a first step of continuously conveying a conveyor jig which supports a preform along a heating conveyor path by using driving force of a first motor;
a second step of intermittently conveying a conveyor arm between a first position and a second position along a direction which is parallel to the heating conveyor path by using driving force of a second motor; and
a third step of transferring the preform from the conveyor jig to the conveyor arm during the conveying of the conveyor arm,
wherein the second step includes a synchronously driving step of causing the conveyor arm which was waiting in the first position to catch up with the conveyor jig which is being conveyed continuously,
wherein the synchronously driving step includes:
a step of detecting an arriving time at which the conveyor jig arrives at a reference position facing the first position based on an output of a first encoder which detects a rotational angle of the first motor; and
a step of commanding the second motor to move the conveyor arm to a target position at regular intervals from the arriving time,

wherein the target position in each command is a position obtained by adding, to a current position of the conveyor jig which is obtained based on a latest output of the first encoder which was obtained when the command has been issued, a moving distance by which the conveyor jig has advanced during a delay time which spans from a time when the latest output is outputted from the first encoder to a time when the command is received by the second motor,
wherein the first step of continuously conveying further includes:
conveying the conveyor jig by an endless chain that has a plurality of connected links; and
driving, by the first motor, a drive sprocket that meshes with the endless chain, and

wherein a distance over which the endless chain moves from the reference position during a synchronously driving period, which is a period during which the conveyor arm staying in the first position is caused to catch up with the conveyor jig by the command, is set less than one fourth of a link length which is a length between supporting points of one link.

Assignees

• Nissei Asb Machine Co Ltd

Inventors

• Tanabe Yoshiaki

Classifications

• B29C49/42085

  holding inside the neck · CPC title

• B29C49/42832

  Moving or inverting sections, e.g. inverting bottom as vacuum panel · CPC title

• B29C49/78

  Measuring, controlling or regulating · CPC title

• B29C49/4236

  Drive means · CPC title

• B29C49/42101 Primary

  Conveyors, e.g. flat conveyor or clamping between two bands · CPC title