Method of predicing injection molding cycle time

Patent metadata

Field	Value
Publication number	US-2016167295-A1
Application number	US-201414568323-A
Country	US
Kind code	A1
Filing date	Dec 12, 2014
Priority date	Dec 12, 2014
Publication date	Jun 16, 2016
Grant date	—

Abstract

The invention features, in general, a method for determining a target cycle time for an injection molded part. The method comprises the steps of ascertaining the solidified volume percentage (V n ) as a function of cooling time (T n ) data for solidification of an injection molded part and calculating a cooling speed indicator (CSI n ) for each data point, (T n ,V n ). The solidified volume percentage (V n ) as a function of cooling time (T n ) and solidified volume percentage (V n ) as a function of cooling speed indicator (CSI n ) are tabulated and used to determine a target cycle time.

First claim

What is claimed is:

1 . A method of determining a target cycle time for injection molding a production part, comprising the steps of:
a. creating a computer based model of an injection molded part; b. creating a computer based model of a mold for an injection molded part; c. ascertaining the solidified volume percentage (V n ) as a function of cooling time (T n ) data for solidification of the injection molded part from V 0 =0% to V total =100%; d. calculating a cooling speed indicator (CSI n ) for each solidified volume percentage as a function of time data point (T n ,V n ); e. determining the solidified volume percentage (V n ) as a function of a cooling speed indicator (CSI n ) data, (CSI n ,V n ), from V 0 =0% to V total =100%; f. determining a Turning Point (CSI n ,V n ) Turning Point for solidified volume percentage (V n ) as a function of a cooling speed indicator (CSI n ) data; g. determining a target cycle time (T n ) corresponding to the solidified volume percentage (V n ) at the Turning Point; and h. applying the target cycle time to the production molded part.

2 . The method according to claim 1 wherein

CSI
n

=

(

Tn
-
Tn
-
1

)

/
Ttotal

Vn
-
Vn
-

1
/
Vtotal

.

3 . The method according to claim 2 wherein the Turning Point, (CSI n ,V n ) Turning Point , is a data point, (CSI n ,V n ), having a minimum value defined by

(
CSIn
)

2

+

(

100
-
Vn

)

2

2

.

4 . The method according to claim 2 further comprising the step of:
a. producing a first graph of solidified volume percentage (V n ) as a function of cooling time (T n ).

5 . The method according to claim 4 further comprising the step of:
a. producing a second graph of the solidified volume percentage (V n ) as a function of a cooling speed indicator (CSI n ).

6 . The method according to claim 5 further comprising the step of:
a. determining a Turning Point on the second graph for solidified volume percentage (V n ) and a cooling speed indicator (CSI n ).

7 . The method according to claim 6 further comprising the step of:
a. determining a target cycle time by finding the cycle time (T n ) on the first graph corresponding to the solidified volume percentage (V n ) at the Turning Point on the second graph.

8 . The method according to claim 6 wherein the Turning Point (V n , CSI n ) Turning Point is the point having a minimum distance to a data point defined by solidified volume percentage (V n )=(V total )=100% and CSI n =CSI 0 =0 wherein

distance
=

(
CSIn
)

2

+

(

100
-
Vn

)

2

2

.

9 . A method of determining a target cycle time for injection molding a production part, comprising the steps of:
a. creating a computer based model of an injection molded part; b. creating a computer based model of a mold for an injection molded part; c. ascertaining the solidified volume percentage (V n ) as a function of cooling time (T n ) data for solidification of an injection molded part from V 0 =0% to V total =100%; d. calculating a cooling speed indicator (CSI n ) for each solidified volume percentage as a function of time data point (T n ,V n ), where

CSI
n

=

(

Tn
-
Tn
-
1

)

/
Ttotal

Vn
-
Vn
-

1
/
Vtotal

;

e. determining the solidified volume percentage (V) as a function of a cooling speed indicator (CSI) data, (CSI,V) from V 0 =0% to V total =100% ;
f. determining a Turning Point (CSI n ,VO Turning Point for solidified volume percentage (V n ) as a function of a cooling speed indicator (CSI) data, wherein the Turning Point, (CSI n ,V n ) Turning Point , is a data point, (CSI n ,V n ), having a minimum value defined by

(
CSIn
)

2

+

(

100
-
Vn

)

2

2

;

g. determining a target cycle time (TO corresponding to the solidified volume percentage (V n ) at the Turning Point; and
h. applying the target cycle time to the production molded part.

10 . The method according to claim 9 further comprising the step of:
a. producing a first graph of solidified vo

Assignees

• Procter & Gamble

Inventors

• Wang Sean

Classifications

• B29C2945/76892

  Solidification, setting phase · CPC title

• G06F2113/22

  Moulding · CPC title

• B29C2945/76558

  termination · CPC title

• G06F30/20 Primary

  Design optimisation, verification or simulation (optimisation, verification or simulation of circuit designs G06F30/30) · CPC title

• B29C2945/76561

  duration · CPC title