FIELD OF THE INVENTION This invention generally relates to a material handling system and more particularly, to a handling system for conveying materials automatically between work stations for fabrication.

DESCRIPTION OF THE PRIOR ART

Garment manufacturing is classically a labour intensive activity that involves a series of sequential steps, primarily comprising designing, pattern making, grading, cutting, bundling, sewing and packaging. Progressive bundle system (PBS) is the traditional garment production system widely used by garment manufacturers for several decades till today. As the name implies, the bundle of garment parts, for example, collars, sleeves, pockets, etc, are moved sequentially, in bundles of 5, 10, 15, 20, 25 or 30 pieces, to feed the operation line. Within the line, a worker brings the bundle to her work station for a particular sewing operation. The worker must first unfasten the bundle for sewing, then she assembles the bundle after she has completed her part and subsequently transfers the bundle to the next worker for upstream sewing operation. Sometimes, factory porters are hired to do this transporting work. But usually, the worker has to stop and leave their work station to look for the bundles.

This is an ineffective practice as wages of a worker is calculated piece-rate, namely, based on the number of pieces she has completed. A worker must carefully count and keep track of the amount of pieces she has completed. Inevitably, the repeating cycle of transferring, unfastening and assembling of bundles, and counting the number of completed pieces results in wastage of time during a working day. In fact, an analysis shows that the time spent by a worker in sewing operation is rather little if compared to the time spent handling the bundles of material. Consequently, various types of systems have been developed and installed in industrial garment manufacturing plants to improve productivity and efficiency, especially material handling equipment and systems to reduce manual material handling by sewing workers and also to reduce material transportation.

For example, an overhead material transport system transports cut pieces for a single garment from work station to work station. All the cut pieces are loaded onto a hanging carrier that travels along an overhead conveyor. This system consists mainly of an overhead conveyor and hanging carriers. It operates much like a railroad track where carriers transport cut pieces along the conveyor to target work stations for a sewing operation. At the completion of an operation, the worker presses a button to move the carrier to the next work station for the next sewing operation.

GB publication no. 2 288 379 A disclosed an overhead conveyor system comprising essentially a guide rail, a plurality of electric movers that can be controlled to stop at a particular station, a hanger to carry an article, and a stopping mechanism disposed at each work station. Each of the electric movers comprises mainly a drive wheel which is driven by a brake-less motor, a photoelectric switch and a first detection member. The stopping mechanism comprises a stopper, a second detection member and a shifting means operatively connected to the stopper and the second detection member to displace the stopper and the second detection member.

In operation, electricity is supplied to the brake-less motor for driving the drive wheel and thereby causes the mover to travel along the guide rail. As the mover reaches a work station where the stopping mechanism is disposed, the photoelectric switch detects the second detection member and interrupts electricity supply to the brake- less motor, resulting in the drive wheel moving forward freely until it hits and is halted by the stopper. Similar stopping manner is adopted by a second mover that travels towards to the first halted mover, namely, the photoelectric switch of the second mover detects the first detection member of the first mover and brings the second mover to a gradual stop to avoid collision. When the first mover is ready to leave the station, the shifting means will displace by pivotably retracting the second detection member and the stoppers away from the guide rail so that the second detection member no longer detected by the photoelectric switch and electricity will be resumed for the brake-less motor to actuate the drive wheel to move forward again.

This overhead conveyor system involves a complicated mechanical structure, particularly in the manner of stopping the movers. For example, when the stopping mechanism of a work station malfunctions this will result in either the mover not stopping or not being able to leave the work station. In the latter situation, all downstream movers will be blocked at the work station where the stopping mechanism malfunctioned and subsequent sewing operations would be affected.

US 6,378,440 Bl disclosed an overhead conveyor system that comprises a track, a chain that runs within the track and is operatively connected to a motor, and a plurality of work piece supporting arms which are mounted to the chain at a predetermined distance relative to the distance between work stations. In operation, the motor is actuated to move the chain which in turns moves the supporting arms to a particular work station. However, the movement of all the work piece supporting arms are controlled relative to the movement of the motor and this can result in several problems. For example, when the motor is not working, the chain which is operatively connected to the motor cannot be moved and hence the entire conveyor system cannot perform its operation. Moreover, the speed of the movement of the supporting arms is predetermined. If a slow worker at one work station cannot catch up with the speed of the line, this would result in an empty supporting arm reaching the next work station. Further, the conveyor system utilizes a track having a combination of straight, curved, inclined and declined track sections. However, the track adopted is not configurable, namely, the track layout is rigid. Once the track is constructed, it has to be used for years until the track layout is no longer practicable or desirable to future projects. At that point in time, this entire track will need to be re-installed.

This invention thus aims to alleviate some or all of the problems of the prior art. SUMMARY OF INVENTION

In accordance with an aspect of the invention, there is provided a material handling system for use in seamed article fabrication. The system comprises a configurable track module having a plurality of directional track sections, the sections being detachably connectable with each other to form a desired track layout and a plurality of transporters detachably mounted to the track sections for conveying materials between work stations. Each of the track sections is provided with a guide conduit. Each of the transporters is provided with an electromechanical switching means that enables the transporter to navigate automatically from one track section to another track section. The electromechanical switching means comprises a solenoid and an electromagnetic navigating switch operatively connected to the solenoid and receivable within the track section guide conduit. In use, selective activation and deactivation of the solenoid causes movement of the navigating switch from one guide conduit to another guide conduit, hence shifting the direction of the transporter and enabling the transporter to navigate from one track section to another track section automatically.

The track section may comprise a track having a U cross-section.

In an embodiment, the track section may comprise a straight track.

In an embodiment, the track section may comprise a curved track.

In an embodiment, the track section may comprise a diverging track.

In an embodiment, the track section may comprise a converging track.

According to an embodiment, the guide conduit may be provided to the bottom at the track section.

In yet another embodiment, the track section may be further provided with a pair of rails disposed along the sides of the track section for the transporter to be slidably mounted and hence running thereon.

In yet another embodiment, the track section may be further provided with a conductor for relaying electricity for the operation of the transporters. The conductor may comprise a plurality of copper nickel alloy strips provided along the sides of the track section.

In yet another embodiment, the track section may further comprise a hall effect sensor for activation of the solenoid of the transporter.

In an embodiment, the transporter may further comprise a moving means and a motor, the motor operatively connected with the moving means. According to an embodiment, the electromagnetic navigating switch may be provided at the top of the transporter so as to be receivable within the guide conduit. The navigating switch may comprise at least one projection slidably disposed within a niche provided at the top of the transporter, the projections shifting either to the left or to the right when the solenoid is actuated.

The moving means may comprise at least a pair of wheels, each disposed at opposing sides of the transporter, and each of which is slidably received within the rail of the track section. According to an embodiment, the transporter may further comprise at least a pair of connectors, each disposed at opposing sides of the transporter and are operatively connected with the conductor of the track section.

According to yet another embodiment, the transporter may further comprise at least a pair of motion stabilizers, each disposed at opposing sides of the transporter.

The transporter may further comprise an infrared data association (IrDA) communication device. The transporter may be further provided with a plurality of anti-collision sensors. The anti-collision sensor may comprise a front sensor. The anti-collision sensor may comprise a side sensor. Anti-collision sensors incorporating infrared technology aid in minimizing the probability of a transporter colliding into another transporter during operation.

In yet another embodiment, the transporter may further comprise an attaching member disposed at the bottom of the transporter for various kind of hangers, baskets, carriers or pallets to be detachably attached thereon.

The material handling system may further comprise a wireless communication arrangement. The arrangement may comprise a control centre, a plurality of communication terminals, each of which is disposed at each work station, and a plurality of infrared data association (IrDA) detectors provided at the track module, whereby instructions from the control centre is transmitted to the transporter. During execution of the instructions, the position of the transporter is detected by the IrDA detector and signals is sent from the IrDA detector to the terminal and to the control centre for data processing. The present invention seeks to overcome the problems of the prior art by providing a material handling system with a simple, flexible and configurable track module which is comparatively inexpensive in construction. For example, when a garment manufacturing process is changed, the track layout can be easily reconfigured to adapt to the change by any ordinary worker without requiring the aid of specialists.

Furthermore, the transporter of the present invention can be installed and dismantled easily and quickly onto and from a track section.

The use of solenoid for the operation electromechanical switching means provides a highly reliable and fast operation, namely, the direction of the transporter can be automatically diverted rapidly. BRIEF DESCRIPTION OF THE DRAWINGS

The invention is illustrated, although not limited, by the following description of embodiments made with reference to the accompanying drawings in which:

Figure 1 shows a material handling system according to the present invention which comprises a configurable track module and a plurality of transporters.

Figure 2 is a perspective view of a straight track section of the present invention.

Figure 3 is a perspective view of a curved track section of the present invention.

Figures 4 and 5 are perspective views of converging/diverging track sections of the present invention.

Figure 6(a) is top view of a right-diverging track section with a transporter moves in the direction of A.

Figure 6(b) is top view of a right-converging track section with a transporter moves in the direction of A'.

Figure 7(a) is top view of a left-diverging track section with a transporter moves in the direction of B. Figure 7(b) is top view of a left-converging track section with a transporter moves in the direction of B'.

Figure 8 shows a connection of right-diverging track section with a left-diverging track section defining a U-turn route.

Figure 9(a) shows a cross-sectional view of the straight track section of Figure 2. Figure 9(b) shows a cross-sectional view of the diverging track section of the present invention.

Figure 10 shows the internal structure of a side wall of the track section of the present invention.

Figure 11 shows the external structure of a side wall of the track section of the present invention. Figure 12 shows the end-to-end securing means which is employed by the present invention in connecting a curved track section to a converging/diverging track section, or connecting a curved track section to another curved track section.

Figure 13 shows the end-to-end securing means of Figure 12 and the end-to-end securing means that connects a curved track section or a converging/diverging track section to a straight track section.

Figure 14 is a front perspective view of a transporter of the present invention. Figure 15 is a front view of the transporter of Figure 13. Figure 16 is a side view of the transporter of Figure 13.

Figure 17 shows the electromechanical switching means according to an embodiment of the present invention.

Figure 18 shows a transporter moving into a diverging track section.

Figure 19 shows a material carrier mounted on to the transporter according to an embodiment of the present invention.

Figure 20 shows a material carrier mounted on to the transporter according to another embodiment of the present invention. Figure 21 shows an embodiment of the transporter where the bottom part of the chassis of the transporter is substituted by an automated material carrier.

Figure 22 shows the automated material carrier of Figure 21.

Figures 23(a) and (b) show the mounting manner of a transporter onto a track section according to an embodiment of the present invention.

Figure 24 shows a transporter moving into a converging track section.

DETAILED DESCIRPTION OF THE EMBODIMENTS

The present invention discloses a material handling system 10 for conveying pieces of material from work station to work station for fabrication into a seamed article.

As shown in Figure 1, the system 10 comprises essentially a configurable track module 20 and a plurality of transporters 40 that travels along the track module.

As the term implies, the configurable track module 20 is a flexible module that allows for easy configuration (and reconfiguration) into any desired track layout for adaptation with different work flow of a particular sewing operation, based on the requirement of individual projects. This is achieved by having a plurality of directional track sections being detachably connectable with each other to form a desired track layout.

The track sections may be of any suitable structure capable of receiving and supporting the transporters 40 to be slidably and removably mounted thereon. For example, in the embodiment shown in Figures 9(a) and 9(b), the track section is essentially a track comprising a U cross-section having a top surface 21 and two side walls 22. Any suitable rigid, light weight and durable material may be used in the manufacture of the track section of this invention. For example, polyoxymethylene, or the like. The track section may be provided in any suitable configuration, for example a straight track section 201, a curved track section 202 or a converging/diverging track section 203, 204. Figure 2 shows a straight track section 201 according to the present invention. The top surface 21 of the track section 201 may be made of aluminum instead polyoxymethylene. It further comprises a longitudinal trench 25 for attaching purposes which will be explained in the following portions of the description. Figure 3 shows a curved track section 202 according to the present invention.

As can been in Figures 4 and 5, a diverging track section 203, 204 comprises a side-bifurcation 23, 24 disposed either to the right side or left side of a straight track section. With reference to the transporter moving in direction of the arrow A, Figure 6(a) is a right-diverging track section 203, whereas in direction of the arrow B, Figure 7(a) is a left-diverging track section 204. In fact, a diverging track section 203, 204 can also be considered as a converging track section if the transporter is travelling in an opposite direction, i.e. in the direction of the arrow A' as can be seen in Figure 6(b), which is now a right-converging track section 203a and in the direction of the arrow B' as can be seen in Figure 7(b), which is now a left-converging track section 204a.

Further, as can be seen in Figure 8, joining a right-diverging track section 203 with a left-diverging track section 204 or a right-converging track section 203a with a left- converging track section 204a defines a U-turn route for the transporters 40. With reference to Figures 9(a) and 9(b), each of the track sections 201, 202, 203, 203a, 204, 204a, particularly diverging track sections, is provided with a guide conduit 26 enabling an electromechanical switching means of the transporter 40 to be receivable therewithin. The guide conduit 26 may comprise a longitudinal groove disposed at the bottom portion of the top surface 21 of the track section.

Each of the track sections 201, 202, 203, 203a, 204, 204a is preferably further provided with a pair of rails 27 disposed along both side walls 22 of the track section for the transporter 40 to be mounted and slidable along the track section. Figures 9(a) and 9(b) show an embodiment of the present invention, where the rails 27 may comprise a pair of lengthwise grooves, disposed along the inner side walls 22 of the track section. One lengthwise edge of the groove is defined by the side wall 22 of the track section while the other lengthwise edge is defined by a vertical flange 27a provided to prevent the transporter 40 from sliding out of the rails 27.

At the lower level of the rails 27, each of the track section 201, 202, 203, 203a, 204, 204a is further provided with a conductor 28 for relaying electricity for the operation of the transporters 40 that travel there along. Optionally, the conductor 28 may be disposed above the rails 27 depending on the structure of the transporter 40 employed.

The conductor 28 may comprise a plurality of pairs of conductor strips attached onto the inner surface of the side walls 22 of the track section. The strips may be attached to the inner surface by way of screwing, riveting or by any other suitable means.

With reference to Figures 9(a), 9(b) and 10, each side wall 22 of the track section 201, 202, 203, 203a, 204, 204a may further comprise at least one pair of inwardly biased flanges 29 forming a through groove 30 for the conductor strip 28 to be embedded therein. Similarly, the strip 28 may be embedded in the groove 30 by way of screwing, riveting or by any other suitable means. It is however preferable that the lengthwise edge of the inwardly biased flanges 29a is further provided with a lengthwise flange 29 so as to retain the strip 28 embedded therein. When attaching the strip 28 in whatsoever manner, both ends 28a of the strip 28 should be bent perpendicularly so that they come into contact with the bent end of the strips of the neighbouring track sections.

Any suitable conductive material, for example, copper nickel alloy or the like may be used. At the same level as the conductor strips 28, each side wall 22 of the track section 201, 202, 203, 203a, 204, 204a comprises at least one slot 31 defining a connector point, where electricity is supplied to the conductor strips 28. Additionally, each of the track sections 201, 202, 203, 203a, 204, 204a further comprises suitable corresponding end-to-end securing means for detachably connecting the track sections with each other. The securing means may be provided at the top surface 21 of each track section. The securing means may be in the form of a butt joint, a mortise and tenon joint, and etc.

For example, in the embodiment of Figure 12, a butt joint is adopted in the present invention. Each end of the curved 202, diverging 203, 204 and converging 203a, 204a track sections is provided with a recess 32 on its top surface 21, on which a screw hole 32a is provided. When connecting a curved track section 202 to a diverging or converging 203, 203a, 204, 204a track section, or connecting a curved track section 202 to another curved track section 202, the recesses 32 of the track sections are abutted and fastened end to end by use of a joining member (not shown), on which corresponding screw holes are also provided. Screws are driven through the holes 32a to hold them in place so as to resist the pulling apart of the joint and also the attached track sections.

However, when connecting a curved 202 or a diverging or converging 203, 203a, 204, 204a track section to a straight track section 201, a mortise and tenon joint may be employed. According to an embodiment of Figure 13 a tenon 33, preferably made of aluminum, is screwed onto the trench end 25 of the straight track section 201, where the tenon 33 is inserted and engaged within the recess (the mortise) 32 provided to the curved or diverging or converging track section. Similarly, screw is driven through the hole 32a on the recess 32 to hold them in place so as to resist the pulling apart of the joint and also the attached track sections.

Each of the track sections 201, 202, 203, 203a, 204, 204a may further comprise suitable fastening means 34 provided to the end of the side walls 22 for safe guarding the attachment between two track sections. The fastening means 34 may be in the form of a snap fit configuration realized by having a plurality of corresponding protrusions and indentations provided to the end surface of side walls of the track sections, where a protrusion of a track section snaps snugly into an indentation provided on the neighbouring track section. As shown in Figures 10 and 11, the end surface of the side walls are provided with screw holes enabling two neighbouring track sections to be fastened together by way of screwing.

A top cover 35 may be further provided to the track sections 201, 202, 203, 203a, 204, 204a to cover their top surface 21 in order to conceal electrical wiring and cables that are running along the top surface, downwardly along the side walls 22 and eventually connected to the conductor strips 28 via the slot 31 to supply electricity. The top cover 35 may be made of any suitable rigid and light weight material. The top cover 35 may be fitted onto the track section by way of a snap fit configuration.

The transporter 40 according to an embodiment of the present invention comprises essentially a moving means 41, a motor (not shown) operatively connected to the moving means 41 and an electromechanical switching means 42.

In an embodiment, the transporter 40 may comprise a suitably designed chassis 43 having a contour to be fitted within the track sections 201, 202, 203, 203a, 204, 204a. The chassis 43 may be made of any suitable rigid material, for example, plastic having thermal resistant effect. At least a pair of moving means 41 are provided with the transporter 40. As can be seen in Figure 14, the moving means 41 may comprise a pair of driving wheels, each wheel disposed on opposing sides of the chassis 43 of the transporter 40. Although not compulsory, it is preferable that the wheels are provided at the upper portion of the chassis. Each wheel is receivable within the rail 27 provided on the side wall 22 of the track section, where the wheel travels along the rail 27 when the motor connected operatively to the wheels is actuated and thereby moves the transporter 40 along the track sections.

When the transporter 40 reaches a diverging track section 203, 204, i.e. where there is an option to switch directions, the electromechanical switching means 42 navigates the transporter 40 to either continue moving straight or to change direction hence turning the transporter 40 to the right or left at the diverging track section 203, 204.

The electromechanical switching means 42 is disposed at the top of the chassis 43 of the transporter 40. It comprises a solenoid (not shown) and an electromagnetic navigating switch 42a operatively connected to the solenoid. In operation, the navigating switch 42a is received by the guide conduit 26 of the track section and slides there along when the transporter 40 moves along the track section. When reaching a diverging track 203, 204, the position of the navigating switch 42a is shifted when the solenoid is operated resulting in switching from one guide conduit to another guide conduit and thereby diverting the moving direction of the transporter 40.

As mentioned above, the navigating switch 41a is disposed at the top of the chassis

43 of the transporter 40. It comprises essentially of a projection received within a niche 42b where the projection is able to shift to the left or right when the solenoid is operated.

According to an embodiment of the present invention as shown in Figure 17, the navigating switch 42a comprises a pair of spaced apart protruding pins slidably disposed within a corresponding pair of niches 42b, and a bridging member 42c connecting both pins at the top. The bridging member 42c is aligned parallel to the guide conduit 26 so that the top portion of the switch 42a is received and engaged within the guide conduit 26 and capable of sliding along. The transporter 40 comprises a motor for its operation. The motor is disposed within the chassis 43. Any suitable motor may be employed, for example, a hybrid DC stepper motor.

The transporter 40 may further comprise a connector 44 for connecting with the conductor strips 28 of the track sections 201, 202, 203, 203a, 204, 204a hence supplying electricity to the motor for the operation of the transporter 40. The connector 44 according to an embodiment of the present invention comprises a plurality of horizontally protruding conductive members disposed at both sides at the chassis 43 of the transporter 40. The conductive members are disposed below the wheels 41 as can be seen in Figures 15 and 16. A plurality of the conductive members

44 are employed in the present invention to avoid interruption of electricity supply for the operation of the transporter 40 when one of the conductive member malfunctions. According to an embodiment of Figure 14, the connector 44 comprises a plurality of horizontal protrusions. Each of the protrusions has a smooth tip surface that interacts with the conductor strips 28 of the track sections 201, 202, 203, 203a, 204, 204a to reduce friction as the protrusions glide on the conductor strips. Any suitable protrusions may be employed, for example, carbon brush.

According to another embodiment, the connector 44 may comprise a plurality of small rollers extending horizontally from the chassis 43 of the transporter 40 and interacting with the conductor strips 28 of the track sections 201, 202, 203, 203a, 204, 204a. The rollers cruise on the conductor strips 28 as the transporter 40 travels along the track sections.

Since the transporter 40 is supported only by having a pair of wheels 41 received within the rails 27 as described above, the transporter 40 may further comprise a motion stabilizer 45 for ensuring the transporter 40 moves steadily along the track sections 201, 202, 203, 203a, 204, 204a. In the present embodiment of Figure 13, a pair of upwardly directed stabilizing members 45 are provided at each side of the chassis 43 of the transporter 40. The stabilizing members 45 on both sides of the transporter 40 press against the bottom surface of the side walls 22 of the track section when a transporter is mounted onto a track section. The stabilizing members 45 are downwardly retractable to prevent the stabilizing members from pressing excessively against the bottom surface of the side walls 22 of the track section which may curb the smooth movement of the transporter 40. Also, this retractable feature enables the stabilizing member 45 to be retracted downwardly so that the transporter 40 can be removed easily from the track section.

In another embodiment, the motion stabilizer 45 may comprise a plurality of downwardly retractable protruding wheels, such as small wheels that press against the bottom surface of the side wall 22 of the track section and run along the track section when the transporter 40 moves along the track sections. In order to retract the motion stabilizer 45, the transporter 40 may further comprise a button 46, mechanically connected to the motion stabilizer, whereby when the button is pressed, it retracts the motion stabilizer downwardly. This is particularly helpful when an operator is dismounting a transporter 40 from the track section as the motion stabilizer 45 would no longer be pressing against the bottom surface of the side walls 22 of the track section. The transporter 40 may further comprise a plurality of anti-collision sensors. For example, a front sensor 47 is disposed at the front of the chassis 43 of the transporter 40 to prevent collision with an upstream transporter. A side sensor is disposed at the both sides of the chassis 43 of the transporter 40 to prevent collision with straight moving transporters when entering a converging track section 203a, 204a. Any suitable kind of sensors may be employed. In general, an infrared sensor is preferable.

The transporter 40 is further provided with an attaching member 48 for various kind of hangers, baskets, carriers or pellets to be detachably attached thereon, hence conveying cut pieces between work stations.

In an embodiment of Figure 15, the attaching member 48 is disposed at the bottom of the chassis 43 of the transporter 40. The attaching member 48 may be a downwardly directed protrusion pivotably affixed to the bottom of the chassis 43. The protrusion is provided with a threaded bore hole extending into the body of the protrusion to enable a hanger, for example, to be screwed therein. Alternatively, the attaching member 48 may be in the form of the hook or loop, and any other similar structure, enabling a hanger to be removably hung thereon. Yet in another embodiment of Figures 21 and 22, the bottom portion of the chassis 43 of the transporter 40 where the attaching member is affixed to, may be dismantled and replaced with an automated telescopic hanger 49.

To mount the transporter 40 onto the track sections 201, 202, 203, 203a, 204, 204a, an operator simply needs to hold the transporter 40 with the direction of both wheels 41 parallel to the guide conduit 26 and insert the transporter 40 into the space within the track section as can be seen in Figure 23(a) and then turn the transporter 90° so that both wheels 41 are now facing the side walls 22 of the track section and mounted onto the rails 27 as can be seen in Figure 23(b). To dismount the transporter 40 from the track sections 201, 202, 203, 203a, 204, 204a, an operator first needs to press the button 46 to retract the motion stabilizer 45, then lift the transporter 40 until the wheels 41 are no longer engaging with the rails 47, and turn the transporter 90° and lower it down. Now, the transporter 40 is fully disengaged and can be removed easily.

According to an embodiment of the present invention, a plurality of hall effect sensors 50 may be provided on the track module 20 at predetermined locations for activating the solenoid, and, by extension shifting the navigating switch 42a of the transporter 40.

The hall effect sensor 50 is normally provided before a diverging track section 203, 204. When a transporter 40 travels pass the sensor 50, it activates the solenoid of the transporter 40 which in turn shifts the navigating switch 42a so that the transporter 40 changes its direction and diverts from one track section to another track section in the manner described above. The electromechanical switching means 42 provides fast and accurate direction change with high reliability.

The material handling system 10 further comprises a wireless communication arrangement. The arrangement comprises a control centre which is typically a computer control centre integrated with a material handling software to plan and monitor the route for each transporter 40, to track and record the input and output of each transporter and to analyse an operation line's production.

The arrangement further comprises a plurality of communication terminals, disposed at each work station and a plurality of infrared data association (IrDA) detectors 60 provided on the track module 20 for communicating with the transporters 40 and the terminals. For example, when a transporter 40 travels pass an IrDA detector 60, a signal is sent to the terminal for recording the time-in and time-out of a transporter 40, hence sending the data to the control centre.

Each of the transporters 40 may be provided with an infrared data association (IrDA) communication device for communicating with the control centre and for relaying signals between the terminals. The communication data between the control centre, the communication terminals, the position detectors 60 and the transporters 40 are preferably sent and received via wireless LAN. Notwithstanding the above, the communication data between the control centre and the communication terminals may be transmitted via cable communication or any other suitable communication method.

In operation, cut pieces of a garment design are arranged and loaded onto a hanging carrier of a transporter 40 to be conveyed between work stations in a sequential order. The route of the transporter 40 is predetermined by the user. When the transporter 40 reaches a work station, it travels pass the IrDA detector 60 and a signal is sent to the terminal allocated to the work station recording time-in of the transporter 40. The worker at the work station starts the sewing operation. When the worker has completed work on the carrier of the transporter 40, a push button next to the sewing machine is pressed and the transporter 40 leaves the work station for the next work station. Again, when the transporter travels pass the IrDA detector 60, a signal is sent to the terminal recording time-out of the transporter 40. The record of time-in and time-out is relayed by the terminal to the control centre. In such a way, production data is recorded by the control centre and can be easily monitored. It is not necessary for a worker to keep track of the quantity of pieces she has completed. The control centre may be connected to a display screen showing real-time input and output data so that all workers within the operation line can see their own record. The same operation manner is adopted for all the transporters within the operation line.

All directional statements such as front/forward, back/ rear, top, bottom, lateral, inward, outward, made herein are relative to the orientation of the assembly, in use.

As will be readily apparent to those skilled in the art, the present invention may easily be produced in other specific forms without departing from its scope or essential characteristics. The present embodiments are, therefore, to be considered as merely illustrative and not restrictive, the scope of the invention being indicated by the claims rather than the foregoing description, and all changes which come within therefore intended to be embraced therein.