9 Mold Design
Content
Dr. Mikó Balázs [email protected]
The role of ejection system BAGIM1ENNB
Design and manufacturing of plastic injection mould
Cause of shrinkage the product will suit tightly to the core Demoulding of the part from the mould
09 – Ejection system
2
Location of the ejection
Ejector plates
Close to the critical areas So large area as it can The deformation of the part is forbidden Aesthetical viewpoint (the mark of the ejection bar)
Stopper / buffer plate
Screw Stopper / buffer plate
Ejector base plate Ejector retaining plate
3
Moving of the ejection plates
The aim of the stopper is to separate the base plate from the clamp plate.
The base plate is thicker than the retaining plate, cause of higher stress and load.
4
Moving of the ejection plates
5
6
1
Moving of the ejection plates
Guide of the ejection plates Loose fit
Loose fit Tight fit
The suggested length of the thread is 1.5 – 2 x d.
Tight fit
Tight fit
This insert ensures this requirement.
Increasing mould size 7
Guide of the ejection plates
8
Guide of the ejection plates
The right fitting is important
Ball-roll guide bush
9
Re-moving of the ejection plates
10
Retainer pin
Ejector bars
Retainer pin
A-plate Pressure insert
Spring The additional role of the springs are the pre-loading of the ejection system (30%).
B-plate Retainer pin Ejector plate
Support pillars Clamp plate 11
12
2
Summary
Cylindrical ejector pin Smooth or stepped Hardened or nitrided
d1=0,8 - 25
d2=0,8 – 2,5 13
Fit in the ejector retainer plate
14
Guide in the B plate or core insert g6/H7
+1
Drilling +1 mm
In general: H7/g6, Or no fitting in order to befeszülés.
3-5xd B-plate Core insert
Ejector retainer plate Ejector base plate
Case of small diameters use larger length .
15
Ensure the angle position
16
Ensure the angle position
Non Parallel straight pin The position of the non-symmetrical ejector bars must be ensure!
17
Perpendicular straight pin
Perpendicular straight pin
With slot 18
3
Kihajlási veszély
Kihajlás
Karcsúsági tényezı λ =
lo
imin =
imin I=
d4
Π I=
b
64
I A
Rugalmas kihajlás: Törıfeszültség:
h3
σt =
Π2 E
12 Ft = Π2
Ft = σt A
l λp : határ karcsúság Ötvözetlen acél: 105 – 89 Ötvözött acél: 112
Fmeg =
λ=
lo imin
λ2
imin =
I A
Imin E lo2
Ft b
b: 2 – 5 (karcsúsággal növekszik
Képlékeny kihajlás: lo=0.5 l
λ ≥ λp : rugalmas kihajlás (Euler) λ < λp : plasztikus kihajlás (Tetmajer)
Törıfeszültség:
σt = 303 – 1.29 λ
(ötvözött acél esetén)
19
Sprue puller
20
Sprue puller
Z-pin
Undercutted insert and ejector pin 21
Rectangular / blade ejector pin
22
Ejection on the rib
b x s = 3,8 x 0,8 – 11,5 x 2,5
The blade ejector is thinner than the rib or we have to modify the part geometry!
The manufacturing of the rectangular „hole” means some problem!
Késkilökı Penge kilökı Lapos kilökı 23
24
4
Ejection n the rib
Sleeve ejector
Part Part
Cylindrical pin
Cylindrical pin
25
Ejector bush
X
26
Stripper plate
27
Stripper plate
28
Ejection by air
Thick wall. 29
30
5
Air valve for ejection
Two steps ejection
One pin moving. 31
Two steps ejection
32
Two steps ejection
One pin moving.
33
Two steps ejection
34
Two steps ejection
One pin moving.
35
Two ejector plates.
36
6
Two steps ejection
Two steps ejection
Two ejector plates.
37
Two steps ejection
38
Two steps ejection
39
Two steps ejection
40
Two steps ejection
41
42
7
Ejection in the A-side
Moving by hydraulic cylinder Sprue bush
Moving/Drive:
Spring Hydraulic cylinder From the B-side
In-mould-cylinder hydraulic system. 43
Round latch lock
44
Spring lock system
45
Latch locking unit
46
Latch locking unit
47
48
8
Latch locking unit
Examples
Strack animation films
49
Robotic demoulding
50
Industrial robot
Install the robot system, communication between the robot and the injection mould machine Enough space for the robot arm and appropriate part surface Robot gripper
51
Grip the part
Ensure the part position
Linear lifter
52
Robot gripper
Put up from the cavity
Mechanical fitting Connect the controllers Robot programming
Mechanical (pneumatic) Vacuum
Put up and hold
h = 0.2 – 0.5 mm
Ejector pin
Linear lifter 53
suction cups
54
9
Mechanical gripper
Vacuum gripper
55
Vacuum gripper
56
Vacuum gripper Adjust possibilities
Vacuum connection
Spring holder Frame Mechanical interface
Suction cup 57
58
10
The role of ejection system BAGIM1ENNB
Design and manufacturing of plastic injection mould
Cause of shrinkage the product will suit tightly to the core Demoulding of the part from the mould
09 – Ejection system
2
Location of the ejection
Ejector plates
Close to the critical areas So large area as it can The deformation of the part is forbidden Aesthetical viewpoint (the mark of the ejection bar)
Stopper / buffer plate
Screw Stopper / buffer plate
Ejector base plate Ejector retaining plate
3
Moving of the ejection plates
The aim of the stopper is to separate the base plate from the clamp plate.
The base plate is thicker than the retaining plate, cause of higher stress and load.
4
Moving of the ejection plates
5
6
1
Moving of the ejection plates
Guide of the ejection plates Loose fit
Loose fit Tight fit
The suggested length of the thread is 1.5 – 2 x d.
Tight fit
Tight fit
This insert ensures this requirement.
Increasing mould size 7
Guide of the ejection plates
8
Guide of the ejection plates
The right fitting is important
Ball-roll guide bush
9
Re-moving of the ejection plates
10
Retainer pin
Ejector bars
Retainer pin
A-plate Pressure insert
Spring The additional role of the springs are the pre-loading of the ejection system (30%).
B-plate Retainer pin Ejector plate
Support pillars Clamp plate 11
12
2
Summary
Cylindrical ejector pin Smooth or stepped Hardened or nitrided
d1=0,8 - 25
d2=0,8 – 2,5 13
Fit in the ejector retainer plate
14
Guide in the B plate or core insert g6/H7
+1
Drilling +1 mm
In general: H7/g6, Or no fitting in order to befeszülés.
3-5xd B-plate Core insert
Ejector retainer plate Ejector base plate
Case of small diameters use larger length .
15
Ensure the angle position
16
Ensure the angle position
Non Parallel straight pin The position of the non-symmetrical ejector bars must be ensure!
17
Perpendicular straight pin
Perpendicular straight pin
With slot 18
3
Kihajlási veszély
Kihajlás
Karcsúsági tényezı λ =
lo
imin =
imin I=
d4
Π I=
b
64
I A
Rugalmas kihajlás: Törıfeszültség:
h3
σt =
Π2 E
12 Ft = Π2
Ft = σt A
l λp : határ karcsúság Ötvözetlen acél: 105 – 89 Ötvözött acél: 112
Fmeg =
λ=
lo imin
λ2
imin =
I A
Imin E lo2
Ft b
b: 2 – 5 (karcsúsággal növekszik
Képlékeny kihajlás: lo=0.5 l
λ ≥ λp : rugalmas kihajlás (Euler) λ < λp : plasztikus kihajlás (Tetmajer)
Törıfeszültség:
σt = 303 – 1.29 λ
(ötvözött acél esetén)
19
Sprue puller
20
Sprue puller
Z-pin
Undercutted insert and ejector pin 21
Rectangular / blade ejector pin
22
Ejection on the rib
b x s = 3,8 x 0,8 – 11,5 x 2,5
The blade ejector is thinner than the rib or we have to modify the part geometry!
The manufacturing of the rectangular „hole” means some problem!
Késkilökı Penge kilökı Lapos kilökı 23
24
4
Ejection n the rib
Sleeve ejector
Part Part
Cylindrical pin
Cylindrical pin
25
Ejector bush
X
26
Stripper plate
27
Stripper plate
28
Ejection by air
Thick wall. 29
30
5
Air valve for ejection
Two steps ejection
One pin moving. 31
Two steps ejection
32
Two steps ejection
One pin moving.
33
Two steps ejection
34
Two steps ejection
One pin moving.
35
Two ejector plates.
36
6
Two steps ejection
Two steps ejection
Two ejector plates.
37
Two steps ejection
38
Two steps ejection
39
Two steps ejection
40
Two steps ejection
41
42
7
Ejection in the A-side
Moving by hydraulic cylinder Sprue bush
Moving/Drive:
Spring Hydraulic cylinder From the B-side
In-mould-cylinder hydraulic system. 43
Round latch lock
44
Spring lock system
45
Latch locking unit
46
Latch locking unit
47
48
8
Latch locking unit
Examples
Strack animation films
49
Robotic demoulding
50
Industrial robot
Install the robot system, communication between the robot and the injection mould machine Enough space for the robot arm and appropriate part surface Robot gripper
51
Grip the part
Ensure the part position
Linear lifter
52
Robot gripper
Put up from the cavity
Mechanical fitting Connect the controllers Robot programming
Mechanical (pneumatic) Vacuum
Put up and hold
h = 0.2 – 0.5 mm
Ejector pin
Linear lifter 53
suction cups
54
9
Mechanical gripper
Vacuum gripper
55
Vacuum gripper
56
Vacuum gripper Adjust possibilities
Vacuum connection
Spring holder Frame Mechanical interface
Suction cup 57
58
10
