A Rotary Type Blow-molding Machine

Based on the design requirements of the motion
curve of blow-station, a Bezier curve is used as the motion curve
of open/close blow-station cam. A multi-objective function for
minimize angular acceleration and pressure angle with
continuous angular jerk constraint is defined. By using 

Augmented Lagrange Multiplier (ALM) method and the theory
of Envelope, the profile of the open/close blow-station cam with
optimal motion curve is obtained. The result of this work
shows the productivity of this machine is increased from
8,000bottles/hrs to 11,000bottles/hrs after using this optimum
designed blow-station cam. It is 37.5% increscent to the
available machine provided by a local company. 

Keywords: Rotary type blow-molding machine,
blow-station cam, optimal design

The advantages of PET bottles are low cost, light
weight, high toughness, stable structure, easy to
transparent and burnish, and high security [1]. Figure 1
shows the skeleton of a rotary type PET bottle
blow-molding machine. The preform is heated up in
the heating zone (VIII), in-feed preform wheel (I)
transmits the perform, and the catch arm of in-feed
preform cam-linkage mechanism (II) picks the preform
from the in-feed preform wheel then send it into the
blow-station (III) to form a PET bottle. The catch arm
of outlet bottle cam-linkage mechanism (IV) picks the
PET bottle take it out of the blow-station and transmits to
the outlet bottle wheel (V) for packing.


In the blow-station device, the blow-station linkage
mechanism is driven by the open/close blow-station cam
mechanism as shown in Figure 2. SI(OIXIYI) is the
fixed coordinate system. Pivots A0 and B0 are incident
to the blow wheel and the blow-station linkage
mechanism, respectively. Coordinate system OMXMYM
is a moving coordinate system attached to the
blow-station linkage mechanism. Angle b is between
start line OIC1 and end line OIC2 of the open/close
blow-station cam. b1 is the open phase angle and b2 is
the close phase angle of the blow-station. RP is a
position vector from OI to A0, RB is a position vector
from OI to B0, qp and qB are the vector angles of the
vectors RP and RB, respectively. qopen is the angle that
blow-station can open. The blow-station is attached to
the blow-station linkage mechanism and the blow-station
linkage mechanism is attached to the blow wheel. The
blow wheel rotates with constant angular velocity
wB counterclockwise. When the blow wheel rotates, the
roller follower contacts the cam and the crank of the
linkage mechanism will be pushed to rotate. The crank
drives the blow-station linkage mechanism to generate
open and close actions. When angle qB is at -d, the
blow-station is about to open. The blow-station is
closed when qB is at (-d+b1+b2). The kinematic
characteristics of the blow-station of a rotary type
blow-molding machine are dominated by its open/close
blow-station cam mechanism.


In the target commercial available machine, the

motion curves, are discontinuous at the interface

position. In order to improve this disadvantage, this
paper proposes an optimal design approach for designing
the profile of the open/close blow-station cam with
continuous angular jerk at the interface position. In
1988, Tsay and Huey proposed an application of
spline functions to the general synthesis of cam motion
programs. In the same year, MacCarthy proposed a
very general spline construction in kinematic design. In
1994, Ting et al. applied the Bezier technique for
motion program synthesis of cam-follower mechanisms.
It shows that any polynomial curve can be obtained
through the Bezier technique by selecting control points.
In 2005, Qiu et al. proposed a new method for
synthesizing the motion curves of cams based on
kinematic or dynamic optimization. In this paper, an
optimal design of the Bezier motion curve with
continuous angular jerk constraint of open/close
blow-station cam is proposed by using ALM optimal
approach. Based on Envelope theory, the profile of the
open/close blow-station cam is obtained. According to
the vector loop method and the definition of pressure
angle, the motion of the follower and the pressure angle
of the cam are analyzed.

II. Design requirements of the blow-station
In Figure 3, PL is the most right side point of the left
mold, PR is the most left side point of the right mold, n1
is a vector perpendicular to the line bf , n2 is a vector


characteristics of the blow-station with different motion
curve.  the angular velocity curve is the smoothest curve at the interface position
between the open phase and the close phase. And, its
peak value  is the lowest among motion curves. A
discontinuous angular jerk Jg in MS, MT, and MCV
motion curves will be generated at the interface position, respectively. And, this will
cause the blow-station to vibrate and noise. However,
the variation of angular acceleration ag at the interface
position is eliminated and its peak value is decreased in
the optimum Bezier motion curve. Therefore, the
angular jerk Jg in the optimum Bezier motion curve is
continuous. Its peak value is also decreased.
According to the results shown in Tables 1 to 3, the r.m.s.
value of angular acceleration of the blow-station in
Bezier curve is decreased by 6.82 %, 13.67 %, and 8.87
% relative to MS, MT, and MCV, respectively. And, the
fluctuation value of angular acceleration is decreased by

11.40 % and 38.87 % relative to MS and MCV,
respectively; but it is increased by 0.19 % relative to MT
curve. The r.m.s. value of angular jerk is decreased by
25.50 %, 31.21 %, and 63.70 % relative to MS, MT, and
MCV curves, respectively. The fluctuation value of
angular jerk is decreased by 43.06 % and 61.71 %
relative to MS and MCV curves, respectively; but it is
increased by 13.2 % relative to MT curve.
Figure 7 is the profiles of open/close blow-station
cam with different motion curves. Figure 8 is the
pressure angles in different motion curves. The peak
value of pressure angle in Bezier curve is obviously
smaller than the other three curves. And the r.m.s.
value of pressure angle with Bezier curve is decreased by 

10.03 %, 11.72 %, and 3.82 % relative to MS, MT, and
MCV curves, respectively. And the fluctuation value is
improved by 29.57 %, 30.58 %, and 30.36 % relative to
MS, MT, and MCV curves, respectively. 

Angular acceleration characteristics of the blow-station and the pressure angle
of the cam are improved. And, by using the designed

open/close blow-station cam mechanism, the vibration

Packing Machines

After each bottle get labeled it must grouped to be packed in carton.
So we need an Incamatic machine to group bottles together and put each group in separated carton.

The carton is shaped in car-toning machine then each carton is felled by Incamatic machine then each filled carton is closed by second car-toning machine.

After that we need a Palatalizing machine to arrange car-tones in layers then put those layers above each other, The number of carton per layer and the number of layers per pallet are predetermined by machine setting.

After that we can shrink the filled pallet b Shrink wrapper machine.

After the Pallet get wrapped it became ready to transferred to the storage area as a product.

Labeling machine

Labeling machine is used to paste label of the product on each bottle.

Labeling machine must has a tank for the glue and it must be heated very well before starting the machine cycle.

almost of Labeling machines use servo motors to obtain high accuracy and very fine movement.

The Labeling machine in-feed is a filled and capped bottles but the out-feed is filled, capped and labeled bottles.

Bottle Conveyor

Bottle conveyor is the conveyor that delivered with filled and capped bottles from filling machine and deliver them to the next stage of the production line.

Bottle conveyor is consist a motor which lead a chain which carry bottles.

Each motor is a leader of a certain length of a chain therefore you must study the number of tracks that the conveyor will carry to determine the power and the speed of each piece of bottle conveyor (motor) to avoid the overload of motors and avoid a falling of bottles due to high speed of motors.

Filling Machines

Filling machine is the machine which filling bottles or CANs with beverages or water.

Filling machine is the most important machine in the production line, the production planning is mainly depend in the bottle per hour that the filling machine can produce.

Filling machine must be connected with pneumatic piping to deliver it with 7 Bar pressured air, and also must be connected with pipes of the main material that you produce like water or beverages.

But you produce a product that the human will consume, therefore you must be have very hygienic system.

To obtain a hygienic product you must design a CPI system to the filling machine which delivered with special  chemical materials and hot water circulated in the pipes and filler to kill any bacteria in pipes which deliver beverages or water to the filling machine.

Some filling machines have built in rains-er  which washing PET bottles with pressured water before it get filled.

After the bottles get filled with beverage it vacuumed and capped very will to be ready to the next stage in production line.

Air Conveyor

Air conveyor is a conveyor that empty bottles hanged on and moved by air pressure to the next stage of production.

Blowers Introduction Animation

In beverages manufacturing air conveyor transfers empty bottles which produced by blowing machine to the filling machine.

But how bottles pushed from the out-feed of blowing machine to the in-feed of filling machine?
You must install several air blowers on the air conveyor to produce pressured air towards the destination by sufficient pressure and sufficient flow rate to can push many bottles in the same time in one line.

The number of blowers you need to install on air conveyor depends on the length of  air conveyor and the number of curves found in air conveyor.

 

Bottle blowing machine

The first machine in production line of beverage industrial plant is the Blowing machine.
Blowing machine is consisting of preform hopper, preform elevator,the oven and blowing part.

The function of Blowing machine is blowing the preforms to be bottles with a good shape to be filled with beverage.

Parts of Blowing machine:
  -The preform hopper is the storage hopper of preforms
  -The preform elevator function is raising the preforms to deliver it to the next part(The oven).
  -The oven function is heating the preforms to increase the elasticity of them to make them easier to be blowing.
  -The Blowing part is the part which blowing the heated preforms in shaped molds,Blowing part can be linear or rotary according to machine design.

The Blowing machine utilities:
    Blowing machine can not working without utilities like pressured air (10 bar) for parts which need air for movement and pre-blowing  of preforms.
It's also need 40 bar air for blowing bottles to make them formed to final shapes.
Blowing machine needs also an in-feed of cooling water for cooling parts of machine during operation, usually blowing machine has chiller which cooling water to feed it to Blowing machine.

When the bottles are ready after blowing process they delivered to air conveyor.

Industrial Area

In this post I'd like to explain how to think and initiate your new industrial business.
As an example let's talk about beverages manufacturing .
First you must think about the area that you will need to install your production line,The production line may be a lot of machines (We will discuss this later).

So you have to study the area of your site and min. area that the production line need
taking in the consideration the area needed to store the materials needed by the all production line, the area needed to each machine materials and the spaces for movement for both forklifts and persons(operators).

You can use software tools to design the layout of the industrial area like Auto-cad to make sure that all spaces you need will be fit before you start transfer and install machines.

Before you start you must make sure that the area you have is processed very will to be qualified to install  the machines to make the ground qualified to withstand the wight and the vibration will done by the machines and you must make sure that the ground has drain channels  in the right places,It's good to make that clear in your layout design.

The production line for beverages manufacturing is consist of several machines, I will mention them here then I will talk about them individually in more details.
Blowing machine,Air conveyer, Filling machine, Labeling machine, Box formatting machine, Incamatic machine, Cartooning machine,Palatalizing machine.

To be continued in next post...