fabrication of gear type injection moulding achine

8/10/2019 Fabrication of Gear Type Injection Moulding Achine

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DESIGN FABRICATION OF GEAR TYPE INJECTION MOLDING MACHINE

PROTOTYE:

ABSTRACT:

The project deals about the injection moulding machine.The main principle is to compress the

plastic material in a barrel and the compressing motion is developed by rotating the gear box

arrangement .The plastic material is heated by the heater surrounding by the barrel .Then it is

converted in to molten state .Then molten plastic is injected through the nozzle in barrel to the

dye by the compressing force .After completing this process, we will get the product from the

die.commercial products like bushes,couplings,switches etc., can be produced. Here we have

fabricated the gear type injection molding machine. Its a new innovative concept. This

equipment has been mainly developed for molding the plastic materials in plastic molding

industries. This equipment is very useful in make the injection molding process. In this

equipment we are using the rack and pinion, motor, heater and control unit for making of such

operations. The performance of plastic gears in wide variety of power and motion transmissionapplications is rather limited due to weak mechanical properties and divergent mechanism of

failures. A methodical simulation is carried out to analyze the gear performance with various

gating system types, gate locations, and processing parameters via grey-based Taguchi

optimization method. With the obtained optimum results in simulation stage, the flow patterns of

polymer melt inside the mould during filling, packing, and cooling processes are studied and the

plastic gear failures mechanism related to processing parameters are predicted. The output results

in the future can be used as guidance in selecting the appropriate materials, improving part and

mould design, and predicting the performance of the plastic gear before the real process of the

part manufacturing takes place.

INTRODUCTION:


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Gears have been in use for more than three thousand years and commonly utilized in

power and motion transmission under different loads and speeds. Due to the fiscal and

practical advantages, the demand of using plastics in gearing industry is significantly

increased and indubitably continues in the future. In comparing with metal gears, plastic

gears have several advantages such as light weight, noiseless running, resistance to

corrosion, lower coefficients of friction, and ability to run under none lubricated conditions

[1, 2]. Plastic gears can be produced by hobbing or shaping, likewise to metal gears or

alternatively by injection moulding. With the continuous expansion of technology, plastic

injection moulding bears itself to considerably more economical means of mass production

to meet the rapidly rising market demand of plastic gearing in various applications.

Injection moulded plastic gears have been used with success in the automotive industry,

office machines, and household utensils, in food and textile machinery, as well as a host of

other applications areas [3]. Unlike metal gears, the potential uses of plastic gear, however,

are rather limited due to weak mechanical properties, poor heat conductors, and tendency

to undergo creep [4]. Apart from that, the plastic gear tooth experiences complex stresses

during service and can fail by divergent mechanism.

Apart from material selection, a proper part or mould design also plays a major role in

getting the most out of plastic gears. A high quality moulded plastic gear starts with the

design and construction of a high quality plastic gear mould. The mould shall always haveproper cooling channels, venting, properly sized gates and runners, ample coring and

ejection capabilities, quality mould surface finish, precision fits and tolerances,

concentricity between mould components, and proper mould material selection. Any

misjudgment in the part and mould design can lead to disastrous consequences on the

plastic gear produced and cause subsequent modifications in the production line, indirectly

incurring high production cost [13]. In the research conducted by Luscher et al. [14], the

number of gates, if kept small, was shown to have a strong influence on the periodicity of

both run-out and long-term transmission error on moulded polyketone gears. However, the

gating scheme had minimal influence on the total magnitude of the errors for the same

gears.


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As plastic materials exhibit extremely convoluted properties, the complexity of the

moulding process makes it very challenging to attain the desired gear part properties. The

intricacy of injection moulding process in producing a wide range of parts with complex

shape including those with tight tolerances [15, 16] has created a very intense effort to keep

the quality characteristic of moulded plastic gear under control. Even if it is possible to

select an optimal material for a specific gear task based on the properties such as strength,

wear, stiffness, damping, and noise production, due to the complexity of injection moulding

process which involving many processing parameters, such as pressure, temperature, and

time, improper setting of processing parameters could negatively affect the final quality of

the moulded plastic gear. In fact, the optimum properties of the plastic material with the

most innovative part and mould design cannot be achieved and become meaningless

without optimum processing parameters during the gear manufacturing. In addition, poor

processing practices relying on experience, intuition, or trial and error in obtaining

information regarding the processing parameters will also create the conditions for gear

failure modes that could not be predicted or accounted for by even the most prudent of

designers.

FABRICATION TECHNIQUES:

`, softening, tempering, stability, the size and shape are important in describing the

method. These methods are different kinds of plastics. Broadly speaking the method may be

discussed under the following headings,

1. MOULDING PROCESS

2. FOAMING PROCESS

MOULDING PROCESS:

In this process the plastics are fabricated under the effect pressure and heat and both

thermoplastics and thermosetting plastics may be starting materials.

INJECTION MOULDING:

Thermoplastics are produced by this method. In this the material is softened by

heating and the hot softened plastic is forced under high pressure into the mold, when it is

set by cooling and the mold is ejected. Injection molding (injection moulding in the UK) is a


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manufacturing process for producing parts by injecting material into a mould. Injection

moulding can be performed with a host of materials, including metals,glasses,elastomers,

confections, and most commonly thermoplasticand thermosettingpolymers. Material for

the part is fed into a heated barrel, mixed, and forced into a mould cavity, where it cools

and hardens to the configuration of the cavity.[1]:240

After a product is designed, usually by

an industrial designer or an engineer, moulds are made by a mouldmaker from metal,

usually either steel or aluminum, and precision-machined to form the features of the

desired part. Injection moulding is widely used for manufacturing a variety of parts, from

the smallest components to entirebody panelsofcars.Advances in 3D printing technology,

using photopolymers which do not melt during the injection moulding of some lower

temperature thermoplastics, can be used for some simple injection moulds.

Parts to be injection moulded must be very carefully designed to facilitate the moulding

process; the material used for the part, the desired shape and features of the part, the

material of the mould, and the properties of the moulding machine must all be taken into

account. The versatility of injection moulding is facilitated by this breadth of design

considerations and possibilities.

Injection Process

With injection moulding, granular plastic is fed by gravity from a hopper into a heated

barrel. As the granules are slowly moved forward by a screw-type plunger, the plastic is

forced into a heated chamber, where it is melted. As the plunger advances, the melted

plastic is forced through a nozzle that rests against the mould, allowing it to enter the

mould cavity through a gate and runner system. The mould remains cold so the plastic

solidifies almost as soon as the mould is filled

I njection moulding cycle

The sequence of events during the injection mould of a plastic part is called the injection

moulding cycle. The cycle begins when the mould closes, followed by the injection of the

polymer into the mould cavity. Once the cavity is filled, a holding pressure is maintained to

compensate for material shrinkage. In the next step, the screw turns, feeding the next shot
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to thefront screw.This causes the screw to retract as the next shot is prepared. Once the

part is sufficiently cool, the mould opens and the part is ejected.

FOAMING PROCESS:

This involves the blowing of a volatile organic liquid, which is entrapped into a polymer

network resulting in the formation of foamed plastics. Foamed polystyrenes are produced in this

process.

COMPONENTS OF GEAR TYPE INJECTION MOULDING MACHINE:

GEAR BOX:

A gearbox is a mechanical method of transferring energy from one device to another and is used

to increase torque while reducing speed. Torque is the power generated through the bending or

twisting of a solid material. This term is often used interchangeably withtransmission.
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Located at the junction point of a power shaft, the gearbox is often used to create a right angle

change in direction, as is seen in a rotary mower or a helicopter. Each unit is made with a

specific purpose in mind, and the gear ratio used is designed to provide the level of force

required. This ratio is fixed and cannot be changed once the box is constructed. The only

possible modification after the fact is an adjustment that allows the shaft speed to increase, along

with a corresponding reduction in torque.

In a situation where multiple speeds are needed, a transmission with multiple gears can be used

to increase torque while slowing down the output speed. This design is commonly found in

automobile transmissions. The same principle can be used to create an overdrive gear that

increases output speed while decreasing torque.

Manual transmission is available in two different systems: sliding mesh and constant mesh. The

sliding mesh system uses straight cut spur gears. The gears spin freely and require driver

manipulation to synchronize the transition from one speed to another. The driver is responsible

for coordinating the engine revolutions to the road speed required. If the transition between gears

is not timed correctly, they clash, creating a loud grinding noise as the gear teeth collide.

GEAR BOX TRANSMISSION:

A machine consists of a power source and a power transmission system, which provides

controlled application of the power. Merriam-Webster defines transmission as an assembly of

parts including the speed-changing gears and the propeller shaft by which the power is

transmitted from an engine to a live axle.[1]

Often transmissionrefers simply to the gearboxthat

usesgearsandgear trainsto providespeedandtorqueconversions from a rotating power source

to another device. The transmission reduces the higher engine speed to the slower wheel speed,

increasing torque in the process Conventional gear/belt transmissions are not the only

mechanism for speed/torque adaptation. Alternative mechanisms include torque convertersand

power transformation
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.

MAIN SHAFT PULLEY:

A shaft is an element used to transmit power and torque, and it can support reverse bending

(fatigue). Most shafts have circular crosssections, either solid or tubular. The difference betweena shaftand an axle is that the shaft rotates to transmit power, and

that it is subjected to fatigue. An axle is just like a round cantilever beam, so it is not subjected to

fatigue.

Shafts have different means to transmit power and torque. For example, it can use gears,

sprockets, pulleys, etc., and also have

some grooves to keep these elements rigid and avoid their vibration, such as key seats, retaining

ring grooves, etc. Also, to be able to

avoid vibration of the elements, and assure an efficient transmission of power and torque, some

changes in the cross-section of the shaft can be made


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The nomenclature is not always clear cut and there is often an overlap of function and therefore

of definition.In general, a ROTATING member used for the transmission of power.

Shaft Diagram

Belt (mechanical):

A belt is a loop of flexible material used to mechanically link two or more rotatingshafts,

most often parallel. Belts may be used as a source of motion, totransmit powerefficiently,

or to track relative movement. Belts are looped overpulleysand may have a twist between

the pulleys, and the shafts need not be parallel. In a two pulley system, the belt can either

drive the pulleys normally in one direction (the same if on parallel shafts), or the belt may

be crossed, so that the direction of the driven shaft is reversed

RACK AND PINION SHAFT:

A rack and pinion is a type of linear actuator that comprises a pair of gears which convert

rotational motion into linear motion. A circular gear called "thepinion"engages teeth on a linear
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"gear" bar called "the rack"; rotational motion applied to the pinion causes the rack to move,

thereby translating the rotational motion of the pinion into the linear motion of the rack.

For example, in a rack railway, the rotation of a pinion mounted on a locomotiveor a railcar

engages arackbetween the rails and forces atrainup a steep slope.

Pinion shafts are present in most gear train assemblies. The pinion shaft transfers the input of

drive shafts (commonly known as cranks) to generate the work for which gear trains are

designed. Pinion gears transfer the drive motion to linear gear assemblies or to 90 bevel gear or

miter gear assemblies. W.M. Berg's high quality pinion shafts are typically single-piece

assemblies manufactured from one piece of steel stock.

NOZZLE:

A nozzleis a device designed to control the direction or characteristics of afluidflow (especially

to increase velocity) as it exits (or enters) an enclosed chamber orpipe.

A nozzle is often a pipe or tube of varying cross sectional area, and it can be used to direct or

modify the flow of a fluid (liquidorgas). Nozzles are frequently used to control the rate of flow,speed, direction, mass, shape, and/or the pressure of the stream that emerges from them. In

nozzle velocity of fluid increases on the expense of its pressure energy.

WORKING PRINCIPLE:

The injection-moulding process is best suited for producing articles made of thermoplastic

materials. Here, the equipment cost is relatively high but the main attraction is the amenability

of the injection-moulding process to a high production rate. In injection molding, a definite

quantity of molten thermoplastic material is injected under pressure into a relatively cold mold

where it solidifies to the shape of the mould.

The injection moulding machine is shown in the process consists of feeding the

compounded plastic material as granules, pellets or powder through the hopper at definite time

intervals into the hot horizontal cylinder where it gets softened. Pressure is applied through a
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hydraulically driven piston to push the molten material through a cylinder into a mould fitted at

the end of the cylinder. While moving through the hot zone of the cylinder, a device called

torpedo helps spread the plastic material uniformly around the inside wall of the hot cylinder

sand thus ensures uniform heat distribution. The molten plastic material from the cylinder is

then injected through a nozzle material from the cylinder is then injected through a nozzle into

the mould cavity.

The mould used, in its simplest form, is a two-part system. One is a movable part and the

other stationary. The stationary part is fixed to the end of the cylinder while the movable part

can be opened or locked on to the stationary part. By using a mechanical locking device, the

mould is proper held in position as the molten plastic material is injected under a pressure as

high as 1500kg/cm. The locking device has to be very skillfully designed in order to withstand

high operating pressures. Further more, a proper flow of the molten material to the interior

regions of the mold is achieved by preheating the mould to an appropriate temperature. Usually,

this temperature is slightly lower than the softening temperature of the plastic material under

going moulding.

After the mould is filled with the molten material under pressure, then it is cooled by cold

water circulation and then opened so as to eject the molded article. The whole cycle could be

repeated several time either manually of in an automated mode.

Base contains the side support, supporting arm and other equipments of this project. The base

contains the molding die on it. The rack and pinion arrangement is mounted on the supporting

arm. The rack is guided by the guide arrangement in this equipment. The raw material is poured

into the barrel, then the heater is switched on and the particular time the Rack and pinion

arrangement is working by the motor get power from automatically through the control unit, the

rack and pinion moves up to down then the molded plastic forcedly moves to the molding die.

The molding die is split able to two parts. So finish the molding process then cool the molding


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die to the required time and remove the molded specimen from the die. This equipment is easily

operateable, used for injection molding needed plastic parts manufacturing industries.

Injection molding is the most important molding method for thermoplastics. It is based on

the ability of thermoplastic materials to be softened by heat and to harden when cooled.

The process thus consists essentially of softening the material in a heated cylinder and

injecting it under pressure into the mold cavity, where it hardens by cooling. Each step is

carried out in a separate zone of the same apparatus in the cyclic operation.

A diagram of a typical injection-molding machine is shown in Figure PP.6. Granular

material (the plastic resin) falls from the hopper into the barrel when the plunger is

withdrawn. The plunger then pushes the material into the heating zone, where it is heated

and softened (plasticized or plasticated). Rapid heating takes place due to spreading of the

polymer into a thin film around a torpedo. The already molten polymer displaced by this

new material is pushed forward through the nozzle, which is in intimate contact with the

mold. The molten polymer flows through the sprue opening in the die, down the runner,

past the gate, and into the mold cavity. The mold is held tightly closed by the clamping

action of the press platen. The molten polymer is thus forced into all parts of the mold

cavities, giving a perfect reproduction of the mold.

The material in the mold must be cooled under pressure below Tm or Tg before the mold is

opened and the molded part is ejected. The plunger is then withdrawn, a fresh charge of

material drops down, the mold is closed under a locking force, and the entire cycle is

repeated. Mold pressures of 8,000000 psi (56212 kg/cm2) and cycle times as low as 15

sec are achieved on some machines.

Note that the feed mechanism of the injection molding machine is activated by the plunger

stroke. The function of the torpedo in the heating zone is to spread the polymer melt into

thin film in close contact with the heated cylinder walls. The fins, which keep the torpedo

centered, also conduct heat from the cylinder walls to the torpedo, although in some

machines the torpedo is heated separately.


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Injection-molding machines are rated by their capacity to mold polystyrene in a single shot.

Thus a 2- oz machine can melt and push 2 oz of general-purpose polystyrene into a mold in

one shot. This capacity is determined by a number of factors such as plunger diameter,

plunger travel, and heating capacity.

The main component of an injection-molding machine are (1) the injection unit which melts the

molding material and forces it into the mold; (2) the clamping unit which opens the mold and

closes it under pressure; (3) the mold used; and (4) the machine controls.

PP.5.1 Types of Injection Units

Injection-molding machines are known by the type of injection unit used in them. The oldest

type is the single-stage plunger unit (Figure PP.6) described above. As the plastic industry

developed, another type of plunger machine appeared, known as a two-stage plunger (Figure

PP.7a). It has two plunger units set one on top of the other. The upper one, also known as a

preplasticizer, plasticizes the molding material and feeds it to the cylinder containing the second

plunger, which operates mainly as a shooting plunger, and pushes the plasticized material

through the nozzle into the mold.

GEAR

Molded Gear Transmission

Molded plastic gears have very little in common with machined gears other than the factthat both use the involute for conjugate action. The differences are quite fundamental.

Machined gears are cut to size with specialized machinery designed specifically for the

task. Molded gears are formed in gear cavities that are usually cut with wire Electrical

Discharge Machines (EDM). These cavities are sized so that the molded gear will shrink to


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the proper size after molding. One cavity might be expected to form more than a million

molded gears.A molding insert tool along side the molded gear

And the gear cavity

A gear cutting manufacturer is charged with the task of cutting gears within

tolerance with every piece made. The gear mold is charged with the task of making one

nearly perfect gear cavity and then processing each gear from that cavity within tolerance

for every piece made. This small but significant difference leads to many other variations.

The differences begin as soon as the choice for molded gears is made.

Design

Molded gears invariably must operate in molded housings. This single fact has

significant consequences. Molded housings and the shafts in them are rarely going to have

the precision tolerances that a machined transmission can provide. The housings and gears

will shrink and expand due to moisture and temperature, perhaps at different rates. The

strength, hardness, and even efficiency of the plastic material will also vary due to local

conditions. Surface toothtemperatures will rise under load, which affects plastic properties.

All of these variables and more dictate a need for custom design of gear teeth.

The advantage the plastic gear designer has is in the application. Most plastic

transmissions are unique. A gear mesh can be designed strictly for its intended function

with a single mating gear. Additionally, the molded gear can be optimized with very little

regard for tooling. Wire EDMs can generate machined patterns with the precision of

CAD. A gear cavity can be made with micron tolerances. Given the fact that traditional

hobs are not required,Diametral Pitch or Module are unimportant specifications. The

involute base circle is the variable ofimportance. Pressure angles can be adjusted in an

analog fashion to balance strength and depth of tooth engagement. Custom designed gearswill offer a great improvement in performance, quietness, and allowable tolerances than

standard gearing.

Comparison of Standard Gear Mesh to Custom Shape Formed Gears


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Molded gears can be made in many forms and varied sizes.

Very Fine Pitch Gear

The Gear Molding Tool

With the gear mesh designed and toleranced, the next step is tool construction. Gear

tooling

must be precise with excellent thermal stability, hardened sleeves and surfaces, exact gear

cavity formation, and designed for high-pressure injection molding. The gear cavity itself

must

be specifically designed for the selected molding material.

There is no way to accurately predict the actual shrinkage for molded plastic gears in a

specific

application. This is due to a number of factors. Most importantly, plastic does not shrink

from

the cavity in an isotropic fashion. The main body of the gear will shrink in a manner that

may be

similar to manufacturers estimations, but the individual tooth is surrounded by steel and

its

cooling pattern will differ from the macroscopic pattern of the larger mass.


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Distinct shrink rates for general plastic gears

A good method to determine shrink requires to two-step approach. Shrink factors are

estimated

for the gear in question. After the tool is made and the first gears are molded, they are then

profile inspected for exact involute geometry. The individual shrink rates are then

determined, a

new cavity is made to the measured shrink and the final gear geometry is properly sized.

Only

profile inspection will be able to accurately determine involute shrinkage. Gear roll testing

may

give some idea of shrinkage anomalies, but it can also give misleading indications.

Sometimes heavily glass filled material is selected for gears due to its low shrink rate.

Shrinkage

then becomes less of an issue in mold design. This approach can also cause its own

problems.

Unfilled engineering resins such as nylon and acetal mold into very precise shapes, albeit

with

shrinkage. Glass filled materials will have knit lines where injection flow fronts merge.

These


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knit lines can cause distortion at the tooth surface as well as localized weak spots on the

gear.

Glass filled gears will generally be much more abrasive during their life than equivalent

unfilled

gears. Generally, filler should only be used when a specific need has been established that

outweighs potential problems.

Mold Processing

All molding is not equivalent. All molding machines are not equivalent. Gears require mold

processing that is exact and repeatable. In general, virgin resin is used for high accuracy

gears.

Even with virgin resin, the material must be of correct dryness, its melt temperature must

be

controlled exactly and repeatably. Injection pressures must be established precisely. The

interaction of the mold tool and process control must also be taken into account.

As plastic is injected at high temperature and pressure, the melt must displace air in the

gear

cavity. Vent paths must be created to allow air to escape, but must be thin enough to stop

the

resin from venting as well. If the vents are too small, gas will be trapped and burning could


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result. If the vents are to big, plastic melt will flow through and cause flash on the part. It is

often advisable for the gearing customer to visit the molding facility before placing the final

order. Just a cursory inspection of molding equipment, general plant cleanliness, inspection

capabilities, and personnel, can help to evaluate their potential for successful molding and

control. For instance, it will be very difficult to mold precision gears in a non-temperature

controlled environment. Molding precision gears in 90% humidity at 100F is fraught with

difficulty.

Inspection

Over the years gear inspection has been refined to discover most errors that trouble cut

gearing.

A profile scanning inspection of the involute profiles is usually done for only a few teeth

around

the gear. Metal gears are produced on turning machinery and patterns can be expected

from

tooth to tooth. Plastic molded gears can have large solitary errors anywhere on any surface

of the

gear. Furthermore, the molding process can introduce a much different kind of error than

in

traditional manufacture.


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Since any molded gear will shrink, the involute profile is a target, not a given value.

Whether

one considers Diametral Pitch, Module, base pitch, pressure angle or any other involute

feature

as the controlling geometry, this feature will be a variable in the actual part. It is necessary

to

set realistic tolerances for these truly variable features.

The Involute Shrinkage of a Molded Gear

Typical errors in a Molded Part

The only way to be certain that a plastic molded gear is within tolerance is by scanning the

involute profile and determining the actual physical geometry of the gear. The molded part

can

be completely out of specification and still give acceptable roll test results. Below is a profile

inspection of such a gear. The involute base circle was very far off the defined value. The

gear

had 64 teeth and a master used to measure the gear had 64 teeth. With such a large

number of


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meshing teeth in roll testing, there was almost no tooth-to-tooth error. The gear simply

appeared

large, even though the base circle was small. The molder thinned the teeth, brought the

gear into

good specification with a roll test, and supplied parts to the customer. The parts

immediately

failed when meshed with a cut metal gear of correct size.

Badly Shrunk Plastic Molded Gear To prevent this type of error the gear must be

completely specified with each variable toleranced.

One such method is recognized by the AGMA in the recently completed Information guide

for

Inspection of Molded Plastic Gears.

NUMBER OF TEETH

BASE PITCH (BASIC DIMENSION)

BASE CIRCLE DIAMETER +/-

BASE CIRCLE TOOTH THICKNESS +/-

ROOT DIAMETER** +/-

OUTSIDE DIAMETER +/-

INVOLUTE FORM DIAMETER max

TIP RADIUS max


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CENTER DISTANCE WITH MASTER GEAR Tbd

MASTER GEAR SPECIFICATION Tbd

TOOTH-TO-TOOTH COMPOSITE ERROR max

PROFILE FORM TOLERANCE (fi) max

**ROOT TROCHOID MUST BE DIRECTLY GENERATED

(RE: AGMA STANDARD 1006-A97 APPENDIX F)

OPERATING DATA

NOMINAL OPERATING DIAMETRAL PITCH

NOMINAL OPERATING MESH ANGLE

NOMINAL OPERATING TOOTH THICKNESS

Suggested Gear Data Specification for Molded Gears

In this approach the base circle geometry of the gear is used as the fundamental control.

The

indirect specification of Diametral Pitch and Pressure Angle are included in the operating

data

field as a reference for traditional analysis.

Gear roll testing is almost always the best way to assure consistency of the molded part in

production. Rather than simply describe allowable Total Composite Error (TCE) or Tooth-

to-


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Tooth error (TTE), the actual center distance with a given master can be specified with

indicated

+/- tolerances. This will provide an easy method to assure that the gears are molding the

same

day after day. Roll tests of sample gears can be gathered to assure both the general form

and the

absolute size of the gears are within tolerance. Roll testing for plastic gears is more like

establishing a roll test signature and confirming that the parts conform to that signature

day

after day.

Typical Roll Test Signature of 10 Molded Gears

The future for plastic molded gears is quite promising. Materials are improving greatly.

Molding

machinery is becoming more accurate. Inspection equipment is now capable of measuring

these

unique parts with great precision. In the future, plastic can be expected to replace metal

gears in

lighter duty applications. They are and will continue to find uses in areas that cannot be

served

by metal gears.

In order to reach these new potentials, every step must be taken correctly and every

advantage


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exploited. The result will be a remarkable new generation of power transmission products.

Prototype Injection Molding

We provide a wide range of prototype injection molded components (featuring plastic gears)

using methods that best meet your requirements.

Our Start to Part(STP) team provides rapid delivery of parts with minimal tool grooming and

limited inspection data to ensure that you have good parts quickly.

Our Production I ntent Prototype service delivers production capable tooling and parts. This

method of prototyping takes into account a customer's need for greater inspection data and the

highest quality of parts.

Comparative Features

While the original concept of the STP acronym was Start To Part, the intent of the group isSteps To Production. Yet it differs from conventional production-quality tooling, as follows:

Production Intent Prototyping

Tooling is owned by the customer and in most cases has customer tool design approval

Tooling is either self contained, in a common frame, or is a single cavity pull-ahead in the

production mold.

Molding process is optimized for tolerances as well as cycle time, which may or may not be

applicable to a production tool.


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QA: full SIR, PPAP, and capability studies are applicable and are made available to the

customer, usu. OEM

Normal delivery

ABA-PGT "Start To Part:

Tooling is owned by ABA-PGT

Tooling is a cavity set in an ABA-PGT owned universal frame

Process optimization is minimized in lieu of speed, yet dimensional characteristics are

monitored for accuracy. Some operator assembly and machining operation may be

incorporated.

Sample inspection reports (SIR) are performed for OD, ID, OAL and gear data. Capability is

reserved for production.

Rapid parts delivery

Applications:

Medical Applications

ABA-PGT works with customers in providing solutions for Surgical Instruments, Biopsy

Instrumentation, Robotics, Dental Implant products, and more...

Automotive Applications

In Automotive, we develop and supply products for Electrical Throttle Controls, Steering

Systems, Instrument Clusters, Window and Door Latch systems, and more.

Business Machine Applications

Whether it is helping to move money in a currency exchange unit, making sure that your

important report prints out right the first time, providing photocopies that are clean and crisp, or

a postal mail machine processing your mail for delivery, ABA-PGT offers cost-effective

solutions for these and many other paper path applications

Miscellaneous Applications


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Water pumps, Small engine transmission, irrigation sprinklers, HVAC, Fractional Motors, Water

& Gas meters, Actuators, Consumer Appliances...

Truth be told...ABA-PGT provides solutions to over 50 different applications.

Injection Molding Machine Control

The FACTSTotal Injection Molding Control (TMC)system integrates and centralizes control

of the entire Injection Molding machine. TheTMC Systemis applicable for all new or existing

injection Molding machines typically larger than 500 ton.

The TMC System provides full integration of the blow molding machine including

control/monitoring of:

Extruder Speed and Temperature

Platen Temperature

Platen Movement

Complete Form Cycle

Control of Injection, Pack & Hold Steps

All Machine Sequence Logic

In addition to our Injection Molding Control System, FACTSprovides:

Heater and Drive Enclosure Assemblies

Drive and Motor Upgrades

Hydraulic Power Package

Total Information Manager

APPLICATIONS:

Batch Mixing Control Systems:


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The FACTS Total Mixing Control (TMC) System for batch processes integrates and

centralizes control of the entire mixing and compounding process. The TMC System is

applicable for all new or existing mixing lines.

The TMC Systemprovides full integration of all line equipment including control/monitoring

of:

Material Handling Systems

Oil Ingredient Weights

Bulk Compound Weights

Minor Compound Weights

Mixer Speed and Temperatures

Mix Time, Temperature and/or Energy

Extruders

Pelletizers

Drop Offs

Batch Offs

In addition to ourTotal Mixing Control System, FACTSprovides:

Recipe Management

Job Scheduling

Weigh Belt Manager


Structural Foam Machine Control

TheFACTSStructural Foam Machine Control System integrates and centralizes control of

the entire Structural Foam machine. The Structural Foam Control Systemis applicable for all

new or existing Structural Foam machines.


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The Machine Control Systemprovides full integration of the structural foam machine including

control/monitoring of:

Extruder Speed and Temperature

Platen Temperature

Platen Movement

Complete Form Cycle

Control of Injection, Pack & Hold Steps


In addition to our Structural Foam Machine Control System, FACTSprovides:


Drive and Motor Upgrades

Hydraulic Power Package


Thermoformer Machine Control

The FACTS Total Thermoformer Control (TTC) System for In-Line and Roll Fed

Thermoformers integrates and centralizes control of the Thermoforming machine. The TTC

Systemis applicable for all new or existing thermoforming machines.

The TTC Systemprovides full integration of the forming machine including control/monitoring

of:

Oven Temperatures

Index Position

Platen Position Movement

Complete Form Cycle

Eject Functions



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In addition to our Total Thermoforming Control System, FACTSprovides:


Servo Drive and Motor Upgrades

Trim Press Integration


Hose, Pipe and Tubing Extrusion Line Control

The FACTS Total Line Control (TLC) System for Hose, Pipe & Tubing Extrusion

lines integrates and centralizes control of the entire extrusion process. The TLC System isapplicable for all new or existing hose, pipe or tubing processes.

The TLC System removes islands of automation and provides full integration of all line

equipment including:

Letoffs

Feed Systems:

o

Volumetrico Gravimetric

Extruder Speeds & Temperatures

Cold Start Protection

Automatic Melt Pump Control

Screen Changers

Internal Air Support Systems

Sizing Tanks

Lappers/Braiders

Gauging:

o Laser Micrometer

o UltrasonicDatasheet 1532-00
http://www.facts-inc.com/wp-content/uploads/2012/04/1532-00-IOW-Gauge-Print.pdfhttp://www.facts-inc.com/wp-content/uploads/2012/04/1532-00-IOW-Gauge-Print.pdfhttp://www.facts-inc.com/wp-content/uploads/2012/04/1532-00-IOW-Gauge-Print.pdfhttp://www.facts-inc.com/wp-content/uploads/2012/04/1532-00-IOW-Gauge-Print.pdf


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Pullers/Capstans

Cutters

Wind-ups/Take-ups

In addition to our Total Line Control System, FACTSprovides:

Heater and Drive System Assemblies

Motor Replacements


MERIT

The daily using components can be easily made.

The cost of the project is very less.

High electricity consumption.

Textile products can be produced.

Less skilled labour is enough.

Different shape of the components can be made according to the die what are

used.

Double-cylinder balanced injection system;

.Multi-stage pressure &speed injection;

Back pressure adjustment device;

Low pressure mold protection;

.Single hydraulic core pulling and inserting;

hydraulic ejector knock-out;

Advantage:

1. T Slot Platen;

2.Machine Weight more than most factory.

3.Machine base use rectangular Tube.


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4pcs safe door are moveable,maintain the machine more easy;

5.Hydraulic tank is moveable,more easy to clean the tank,

6.heating band is made by cermics,use life is long

7.prepare more spare parts for customer

DISADVANTAGES

Additional Cost is required for Gear box and motor.

Heating coil consumes high current

Conclusion:

The findings of fabrication experiment reveal that the advancement of the simulation packages

is capable of simulating the scenarios of the polymer melt without conducting the real

experiment. As in this study, MPI software is a useful tool to predict volumetric shrinkage and

deflection of the moulded gear under different process conditions. The integration of the grey-

based Taguchi optimization method and numerical simulation provides designers and engineers

with a systematic and efficient approach to identify the most significant processing parameters

on the quality characteristics of the final moulded gear out of numerous processing variables

with minimal simulation trials required. Through a series of analysis and optimization, it was

found out that gate types and locations have a great influence on the filling pattern or the

transient progression of the polymer flow front within the feed system and mould cavity.

Predicting and visualizing the filling pattern in mould cavity using simulation packages before

the real manufacturing process takes place reduces the incurring high production cost due to

subsequent mould modification in production line as well as minimizing the potential aesthetic

issues in the moulded gear.

fabrication of gear type injection moulding achine

Documents