|Title of Invention||
PRODUCTION MONITORING SYSTEM FOR SEWING MACHINES IN A GARMENT MANUFACTURING UNIT
|Abstract||A production monitoring system for a series of sewing machines in a garment manufacturing unit,said system comprising : for each sewing machine, - a wheel plate (1) rotatably mounted on the main shaft of the sewing machine; a sensing means (3) mounted in front of said wheel plate and spaced at a distance from the wheel plate; a reflective tape or reflective material (5) fixed on said wheel plate; and a work station (7) connected to said sensing means and to a master computery(8), said master computer displaying the data received from the work station.|
|Full Text||FORM 2
THE PATENTS ACT, 1970 (39 of 1970)
COMPLETE SPECIFICATION (See Section 10; rule 13)
PRODUCTION MONITORING SYSTEM FOR SEWING MACHINES IN A GARMENT MANUFACTURING UNIT
AHMEDABAD TEXTILE INDUSTRY'S RESEARCH ASSOCIATION of P.O. AMBAWADI VISTAR, AHMEDABAD 380 015, GUJARAT,INDIA A SOCIETY REGISTERED UNDER THE SOCIETIES REGISTRATION
ACT, XXI OF 1860
NATIONAL INSTITUTE OF FASHION TECHNOLOGY PLOT NO. E/4, GIDC ELECTRONIC ESTATE, SECTOR-25 GANDHINAGAR 382 044, GUJARAT, INDIA
The following specification particularly describes the nature of this invention and the manner in wh-jr-h it is to
The present invention relates to a production monitoring system for sewing machines in garment manufacturing unit having means to continuously monitor the event undergoing at a particular sewing machine and of the sewing room as a whole.
In the garment manufacturing industry, the shop floor production information is gathered manually at the end of the day and the planning is thereafter, made for the next day. This results in poor system efficiency, (around 60% to 70%). Apart from that, in the majority of the industries, this type of planning is not done, the obvious reason for which, is non¬availability of timely information. Usually present Indian Ready Made Garment (RMG) industry has a postmortem approach.
It is therefore necessary that the manager/supervisor should do the planning very often in a day to improve the production. For that, one should have accurate and latest information of individual machines in the sewing room.
So there is dire need to develop a system which can reduce the various production losses in Indian garment industry in order to compete in the global market.
The production losses in the sewing room are mainly of two kinds, viz. unavoidable losses and avoidable losses.
Unavoidable losses are machine set up time, some material handling, personnel fatigue time, inspection and instruction to operator, delay allowances like rethreading, bobbin change, needle change etc.
Avoidable losses are response time for system balancing, poor floor planning, reduction in size of bottleneck operation, frequent machine breakdown, excessive material handling, late starts, early stops, low speed, and extensive breaks.
Absolutely there is no doubt that the greater benefit is due to increased machine uptime. The greatest productivity loss comes from idle machines. Unavoidable machine idle time can be controlled and probably reduced. But avoidable machine idle time represents significant opportunity for productivity improvement through management action. If production managers or supervisors get timely and precise information, with which they can routinely assess the performance and isolate the problems, this improves the production.
The present invention provides a production monitoring system for a series of sewing machines in a garment manufacturing unit, said system comprising : for each sewing machine, -
a wheel plate rotatably mounted on the main shaft of the sewing machine;
a sensing means mounted in front of said wheel plate and spaced at a distance from the wheel plate;
a reflective tape or reflective material fixed on said wheel plate; and
a work station connected to said sensing means and to a master computer, said master computer displaying the data received from the work station.
In this system, the sensing means preferably comprises an
optical sensor, and more preferably comprises of an infrared
light transmitter and receiver. Alternatively, the sensing.
means may comprise a proximity switch . The master computer is
connected to a program memory for storing sOftwaref program 'and „'
a data memory provided in the work station. The optical sensor
is in communication with the program memory, a RS 485 serial-"" '
communication port, a real time clock, the data memory, a
keyboard and a 2-line LCD display. The sensing means is
preferably mounted on the sewing machine,preferably,by means
of a bracket.
One embodiment of the invention will herein-after be
described with reference to the drawings accompanying the
provisional specification wherein -
Fig.l shows diagrammatically a sewing machine
incorporating the monitoring system of the present
Fig.2 shows the arrangement of the wheel plate and
optical sensor of Fig.l and a reflective tape;
Fig.3 shows diagrammatically work stations connected to
a master computer;
Fig.4 shows diagrammatically the monitoring system.
Detailed description of the Invention
The system consists of a reflective tape, a sensing means
such as a non-contact optical sensor (reflectance type), a
sensor-holding device, a single board microcomputer called
Workstation,wiring and a Host Computer called Master(or Master
As shown in Fig.l, wheel Plate 1 is mounted on the main shaft (not show) of the Sewing Machine 2. The Wheel Plate' 1 rotates when the sewing machine is in the ON position. A sensing means such as a non-contact type Optical Sensor 3 is mounted in front of the Wheel Plate 1 at a suitable distance' on a Bracket 4. Alternatively, the signal can also be generated by any other means from any of the moving parts or the part which helps in switching the machine ON or OFF. For eg., the optical sensor may be replaced by a proximity switch.
The schematic arrangement of Wheel Plate 1, Reflective Tape 5 and Optical Sensor 3 is shown in Fig.2. The Optical sensor 3 senses the status of the sewing machine, i.e. whether the machine is ON or OFF. The Optical Sensor, consists of an infrared light transmitter and a receiver. Whenever Reflective Tape 5 comes in front of Sensor 3, light transmitted from the sensor on to the -reflective tape returns and output voltage level of the sensor changes. Thus, the sensor changes its output state whenever the machine is running above certain speed and maintains it as long as the machine is running at that speed.
Each sewing machine is equipped with one Workstation. Each work-station 7 is connected to the Master 8, which is kept at a suitable place and connected through wires 9 as shown in Fig.3. In Fig.3 work stations are indicated by A,B,C...Y,Z.
Each workstation 7 collects data like machine ON time, piece-handling time, piece stitching time, bundle entry and" exit time etc. Each work station stores data in memory and on demand from Master 8, it offloads the stored data to the Master Computer. The computer analyses the data and generates various reports like production, material on shop-floor, location of each piece, efficiency of operator, status of job on hand etc. These reports provide valuable and important information to the managers, supervisors and customers at any time. It also provides cost effective logistics of material movement to meet a planned schedule. It also builds up the data bank for generating norms for standard stitching time of various processes, labour skill inventory etc.
System is divided into three parts, namely -
The hardware consists of an 8-bit single chip micro controller 15 based system. As shown in Fig.4, it has a 64KB program memory 14 to store monitor program, a 64KB data memory 6 and a 4 x 4 matrix keyboard 10 for data input manually. It has 16 characters, 2 lines LCD display 11 to-display information like ongoing bundle number, pending bundle number etc. It has got a RS485 serial communication port 12 for data trans-receive. It has also a Real Time clock 13 to get various event times.
Movement of data is handled using RS485 serial communication method. RS485 is a specialized inter face that
would not be considered standard equipment on' today's home PC but is very common in the data acquisition world. RS485 supports 32 drivers and 32 receivers and with a repeater if supports another 32 drivers and receivers. Maximum cable length can be as much as 4000 feet because of the differential voltage transmission system used. Using RS485 technique, a single PC is connected to several addressable microcomputer boards sharing cable. Thus it saves cable cost. Since it employs differential voltage transmission technique, data are transmitted efficiently.
Software has been developed in Assembly language, which runs on single board microcomputer and keeps track of various events like machine on time, machine off time, piece completion time, piece handling time, bundle/piece monitoring etc. It stores these events data in data memory and sends stored data to host computer on demand.
Software uses Visual Basic as well as in Access, which collects data generated at each station at regular interval, analyzes the collected data and upgrades various reports. It also allows user for inputing various other data manually.
Name of the operator
Production grid diagram
Operationwise Piece rate/daily wage/monthly salary:.
Target output per operator. .
Management Information and Reports Generation
The system can generate following types of reports, i. Status of complete sewing floor at every 3-minutes
interval. ii. Operationwise and product's actual Standard Allowable
Minutes (SAM). iii. Operator/machine wise daily performance report, iv. Operation/operator/machine-wise Needle Down Time &
Handling, v. Development and continuous up-gradation of Skill matr
chart. vi. Work in Progress (WIP) status of the floor, vii. Estimated order completion time at the beginning of
order planning. viii.Per day expected output and actual output, ix. In case of piece rate system daily earning of the
operator. x. Order-wise detail of direct labour cost, xi. Rejection/rework level machine and operator-wise. xii.Back tracing of the garment.
Flow of information to and from the production floor is automated through more accurate set up standards, such as -i. Operatorwise/machinewise/operationwise production data, ii. Accurate & fast product base costing, iii. Improvement in training programme, iv. Fast identification & removal of Bottleneck in
operation, v. Generation of SAM.
vi. Easy development of Skill Matrix Chart, vii. Upgraded material handling procedures, viii.Total work in process, ix. Machine downtime x. Differentiation between needle time and material
handling time, xi. Actual throughput time.
xii. Reduce the response time to problem identification, xiii Bench-mark can be developed for the production system.
These benefits all contribute to improve production, lower unit production cost and to execute the order in time.
Although the invention has been described with reference to a preferred embodiment, the invention includes all modification falling within the scope of the invention as hereinafter claimed.
We Claim :
1. A production monitoring system for a series of sewing
machines in a garment manufacturing unit,said system
for each sewing machine, -
a wheel plate (1) rotatably mounted on the main shaft of the sewing machine;
a sensing means (3) mounted in front of said wheel plate and spaced at a distance from the wheel plate;
a reflective tape or reflective material (5) fixed on said wheel plate; and
a work station (7) connected to said sensing means and to a master computery(8), said master computer displaying the data received from the work station.
2. The monitoring system as claimed in claim 1, wherein said sensing means comprises an optical sensor.
3. The monitoring system as claimed in claim 2, wherein said optical sensor comprises an infrared light transmitter and receiver.
4. The monitoring system as claimed in claim 1, wherein said sensing means comprises a proximity switch.
5. The monitoring system as. claimed in any of claims 1 to 4, wherein said sensing means is mounted on a bracket attached to said sewing machine.
6. The monitoring system as claimed in any of claims 1 to 5, wherein said master computer is connected to a program . memory for storing software program and a data memory provided in said workstation, said sensing means being in communication with said program memory.
7. A production monitoring system for a series of sewing machines, substantially as herein described, particularly with reference to the accompanying drawings.
|Indian Patent Application Number||973/MUM/2002|
|PG Journal Number||30/2007|
|Date of Filing||11-Nov-2002|
|Name of Patentee||AHMEDABAD TEXTILE INDUSTRY'S RESEARCH ASSOCIATION|
|Applicant Address||P.O. AMBAWADI VISTAR, AHMEDABAD 380 015, GUJARAT, INDIA.|
|PCT International Classification Number||D05B 25/00|
|PCT International Application Number||N/A|
|PCT International Filing date|