Title of Invention	AUTOMATED THREAD ROLLING MACHINE
Abstract	The present invention relates to an automated thread rolling machine for eliminating rolling working of undersize, low hardened/high hardened components. The present invention also relates to a method for eliminating rolling working of undersize low hardened/high hardened components.

Full Text

FIELD OF THE INVENTION The present invention relates to an automated thread rolling machine for eliminating Rolling/working of undersize, low hardened/high hardened components. The present invention also relates to a method for eliminating rolling/working of undersize, low hardened/high hardened components. BACKGROUND OF THE INVENTION Circular thread Rolling Machines are used to form threads on fasteners and other Threaded components, profiles such as spine etc. with close accuracy and geometrical tolerances. Circular Thread Rolling Machines are used for rolling of threads using two rotating rollers and a work rest blade having desired thread profile. The two rotating rolls and work rest blade provide a three-point support for the blanks that are to be rolled and fix the geometric center for the system. This is called centreless operation for producing accurate thread profiles with close geometric accuracy of the rolled parts. The accuracy of products produced depends on a number of factors like machine condition, part condition, tool condition etc. A paired rolls having multi start thread profile are assembled on two shafts of the machine, either one of the rolls will be fixed and other one will be moving or both the rollers are moving in opposite direction. The work rest blade is positioned in such a way that when a part is fed on to the blade, the center of the part will be same as roll center after rolling. The rolls are driven by electric motor and will be rotating at the same speed. The rolls will apply pressure through hydraulic power pack. The operation sequence is as follows: - rolls are assembled and checked for matching; - work rest blade center is checked for correct height; - roll motor is switched on and the rolls start rotating in desired direction; - hydraulic motor is switched ON; - parts are manually fed on to the work rest blade; - tip of the part is stopped against a positive stopper to ensure constant threaded length; - when Cycle start button is pressed, moving rolls will advance with fast approach and at a preset position will change over to slow speed and high pressure, the rolling of parts are completed and the rolls will reach set position, this is to ensure consistent thread dimensions. - rolls will return to home position and ready to start next cycle; and - part is unloaded manually on to the collection bin. Presently, the auto manufacturers are introducing automated assembly lines. Parts are directly fed into the assembly line without any incoming inspection and human involvement. Hence, the parts have to be defect free and have consistent quality. Any mixing of similar parts entering into the automated assembly line may cause stoppage of line. Customers insist on defect free supplies that can be directly fed to assembly line without any incoming inspection also, maintaining just in time inventory, no scope for rejection and segregation. This necessitates the supplies to have a robust system at manufacturing station to have defect free products. The final quality inspection by way of sorting is a time consuming process and also it does not provide the guarantee of 100% defect free supply as expected by the customer. Hence there is a long felt need for developing a system which removes the necessity of inspection and produces defect free products and 100% confirmation to specification of the products. All systems used for detecting bad parts in manufacturing process used either a force sensor or only a distance sensor. This invention uses the force and distance sensor in conjunction and develops a relation between distance and force based on which the product evaluation and subsequent rejections are done. Force-distance relationship also enables tool to be withdrawn on overload and therefore preventing damage to tools, machine etc. This system uses a combination of force and distance to segregate parts in manufacture to ensure zero defect and can be used on any manufacturing operation where a co-relation exists between distance and force. OBJECTS OF INVENTION The main object of the present invention is to provide a method for eliminating rolling/working of undersize, low hardened/high hardened components and a method to perform the rolling operation. An object of the present invention to provide a thread rolling machine for checking the correctness of the input materials, mix up of similar parts and misfeeds. Another object of the present invention is to provide a thread rolling machine for checking runup/pull down parts and incorrect blanks of length, bent blanks and any under size/over size blanks getting into blanks. Yet another object of the present invention is to provide a thread rolling machine for checking die wear, and die chipping. Still another object of the present invention is to provide a thread rolling machine for checking the hardness of the input material and segregating any unhampered parts from getting into rolling cycle, products that have not completed in previous operations. One another object of the present invention is to provide a thread rolling machine for detecting the materials which deviate from a pre-determined set of values for the various parameters discussed above or which have some abnormalities due to machine condition or input material variation or roll conditions and marking it as a bad part. Yet another object of the present invention is to provide a machine wherein both displacement sensors and force sensors are used conjunctively. Yet another object of the present invention is to provide a thread rolling machine for segregating any bad parts. Further object of the present invention is to protect the machine from overloading and causing damage to machine part, which is done by preventing rolling operation when blanks are out of specification at the start of rolling. Yet another object of the present invention is to provide a thread rolling machine for checking the correctness of the input material in terms of size and shape hardness, monitoring the force applied during rolling and detecting and segregating bad parts at the delivery end when any departure from a preset value or any abnormality occurs during thread rolling either due to machine condition or due to input material variation or roll conditions. STATEMENT OF THE INVENTION The present invention relates to an automated thread rolling machine for eliminating rolling/working of undersize, low hardened and high hardened components and to obtain zero defect products, said machine comprising:a force sensor used in conjunction with a displacement sensor; a force amplifier;a timing sensor; a movable slide with a rolling head having a thread rolling die; a fixed slide with a rolling head having a thread rolling die; a roll motor to start the rolls; an end stopper with touch sensor to confirm the component; the thread rolling dies are mounted on two shafts rotating in same direction; a work rest blade; a control system; a man machine interface unit (MMI); an ejector to eject components after rolling; a cycle start button to start the process cycle; a dumper; a hydraulic motor; a hydraulic system; an auto feeder unit; and a collection bin; and a method of eliminating rolling/working of undersize and low hardened/high hardened components with an automated thread rolling machine, said method comprising the steps of: assembling the rolls; switching on the roll motor to enable rolls to rotate in the desired direction; switching on the hydraulic motor; feeding parts on to the work rest blade; moving the slide and contacting the tip of the part with the end stopper which has a touch sensor housed in it to send a signal to CPU, which in turn sends signal to the hydraulic system for starting a new cycle; measuring the reference distance from distance between the moving slide and the part with correct size and storing in the Man Machine Interface(MMI); measuring average force in semi auto mode; switching on the cycle start button to start the moving roll; advancing the roll to contact the part; tracking the distance by the distance sensor at which the rolls contact the part and transmitting to the CPU; comparing with the reference distance as stored in MMI; sensing the touch force and transmitting the signals to CPU where they will be compared with a pre-determined reference distance to verify the correctness of the blank size; ejecting the suspect part out and separating at dumper box and transferred to rejected bin automatically; and moving forward the rolls to carry out thread rolling operation to obtain zero defect threaded products. DETAILED DESCRIPTION OF THE INVENTION An embodiment of the present invention is to provide an automated thread rolling machine for eliminating rolling/working of undersize, low hardened and high hardened components and to obtain zero defect products, said machine comprising: (a) a force sensor used in conjunction with a displacement sensor; (b) a force amplifier; (c) a timing sensor; (d) a movable slide with a rolling head having a thread rolling die; (e) a fixed slide with a rolling head having a thread rolling die; (f) a roll motor to start the rolls; (g) an end stopper with touch sensor to confirm the component; (h) the thread rolling dies are mounted on two shafts rotating in same direction; (i) a work rest blade; Q) a control system; (k) a man machine interface unit (MMI); (1) an ejector to eject components after rolling; (m)a cycle start button to start the process cycle; (n) a dumper; (o) a hydraulic motor; (p) a hydraulic system; (q) an auto feeder unit; and (r) a collection bin. An embodiment of the present invention, wherein the force sensor is a quartz crystal that develops a potential difference when subjected to pressure. Another embodiment of the present invention, wherein the force sensor generates a potential difference of 0 to lOV when subjected to pressure. Yet another embodiment of the present invention, wherein the force sensor verifies the correctness of the parts by ensuring the correct dimensions of the parts. Still another embodiment of the present invention, wherein the displacement sensor is a laser sensor. Further embodiment of the present invention, wherein the displacement sensor gives an output of ± 4V corresponding to the linear distance of ±40 mm covered by the movable slide. Yet another embodiment of the present invention, wherein the displacement sensor will scan the movable slide through out the movement and also ensures constant stopping position at the end of the travel of the slide. Further embodiment of the present invention, wherein the force amplifier is an electronic unit, which amplifies millivolts, received from force sensor to a measurable voltage. Yet another embodiment of the present invention, wherein the timing sensor is used to regulate the force amplifier. Still another embodiment of the present invention, wherein the timing sensor is a proximity switch, which will be switched ON during rolling to provide an electric signal voltage to force amplifier and switches OFF to reset the amplifier. Yet another embodiment of the present invention, wherein the movable slide having the rotating thread rolling die moves from the rest position to the location of the part. Further embodiment of the present invention, wherein the fixed slide having the rotating thread rolling die. Still another embodiment of the present invention, wherein the fixed and movable rolls consist of multi start thread profile. Yet another embodiment of the present invention, wherein the rolling dies are driven by the roll motor and move at a constant speed. Still another embodiment of the present invention, wherein the end stopper with touch sensor housed in it confirms the component and permits the slide to move forward for rolling operation. Further embodiment of the present invention, wherein the rotation of the shaft is from a motor. Yet another embodiment of the present invention, wherein the shafts are supported by suitable bearings. Still another embodiment of the present invention, wherein two thread rolling dies are mounted on each shaft. Further embodiment of the present invention, wherein the work rest blade in positioned to ensure that the centre of the part will be same as roll center after rolling. Yet another embodiment of the present invention, wherein the control system receives signals from the sensors, compare it with a predetermined value and sends command to machine elements to perform task based upon the sensed signal. Further embodiment of the present invention, wherein the control system is a programmable Logic Controller consisting of a processing unit, input/output modules. Yet another embodiment of the present invention, wherein the input/output modules of said control system is selected from digital and analogue systems. Further embodiment of the present invention, wherein the Man Machine Interface Unit (MMI) provides interface between operator and the Control System. Yet another embodiment of the present invention, wherein the Man Machine Interface Unit (MMI) is used for entering control parameters selected from force and distance directly. Further embodiment of the present invention, wherein Man Machine Interface Unit (MMI) displays reference distance, force values during 10 sample mode and load values generated during each rolling cycle. Still another embodiment of the present invention, wherein the Man Machine Interface Unit (MMI) provides means for assessing the samples before the machine enters the auto mode. Yet another embodiment of the present invention, wherein the ejection mechanism with touch sensor is used for product confirmation and to eject the part of the machine as per confirmation signal received from Displacement sensor. Further embodiment of the present invention, wherein the dumper segregates good and bad parts at the delivery end, based on the signal received from Control System. Still another embodiment of the present invention, wherein the component to be rolled fed by means of an automatic feeding loading device. Yet another embodiment of the present invention, wherein the collection bin is used to collect the threaded parts. Further embodiment of the present invention, wherein the combination of force and distance references is used to segregate parts during the manufacture and to ensure zero defect. Still another embodiment of the present invention, wherein a consistent thread dimensions of the parts are obtained as the distance sensor ensures that the rolls reach a constant position at the end of the operation by comparing the distance moved with the pre-determined position. Yet another embodiment of the present invention, wherein said machine is used to check die wear and die chipping. Further embodiment of the present invention, wherein said machine is used to check run up, pull down parts, incorrect parts of length, bent parts and under size/over size parts. Yet another embodiment of the present invention, wherein said machine is used for any manufacturing device wherever force/displacement co-relation exists, more preferably for circular thread rollers. Still another embodiment of the present invention, wherein pressure is set in the range of 6-8 bar to prevent the roll from creating an impression on the parts. The present invention also provides a method of eliminating rolling/working of undersize and low hardened/high hardened components with an automated rolling thread machinery device, said method comprising the steps of: (a) assembling the rolls; (b) switching on the roll motor to enable rolls to rotate in the desired direction; (c) switching on the hydraulic motor; (d) feeding parts on to the work rest blade; (e) moving the slide and contacting the tip of the part with the end stopper which has a touch sensor housed in it to send a signal to CPU, which in turn sends signal to the hydraulic system for starting a new cycle; (f) measuring the reference distance from distance between the moving slide and the part with correct size and storing in the Man Machine Interface(MMI); (g) measuring average force in semi auto mode; (h) switching on the cycle start button to start the moving roll; (i) advancing the roll to contact the part; (j) tracking the distance by the distance sensor at which the rolls contact the part and transmitting to the CPU; (k) comparing with the reference distance as stored in MMI; (1) sensing the touch force and transmitting the signals to CPU where they will be compared with a pre-determined reference distance to verify the correctness of the blank size; (m)ejecting the suspect part out, separating at dumper box and transferring to rejected bin automatically; and (n) moving forward the rolls to carry out thread rolling operation to obtain zero threaded products. An embodiment of the present invention, a method wherein the rolls are assembled to ensure matching by positioning the two dies so that the crests of one die are exactly opposite the roots of the other at the point of rolling contact with the work piece. Yet another embodiment of the present invention, a method wherein the matching of the two dies is ensured by positioning the dies in such a way that crest and root of the threads are matched. Further embodiment of the present invention, a method wherein the desired direction of the rolls depends on the type of thread to be rolled on blank, which is selected from Left thread or Right thread. Yet another embodiment of the present invention, a method wherein the component is fed by means of an automatic bolt loading device. Still another embodiment of the present invention, a method wherein in semi auto mode is used during initial setting of the machine to perform a single cycle of operation. Further embodiment of the present invention, a method wherein the distance sensor will scan the slide through out the movement of the slide during the operation. Yet another embodiment of the present invention, a method wherein the distance sensor will ensure that the rolls reach a constant position at the end of the operation by comparing the distance moved with the pre-determined position, thus ensuring constant minor diameter of the product, which is an indicator of consistent thread dimensions. Further embodiment of the present invention, a method wherein when the force-measuring sensor feels force value beyond set limit, a signal is sent to dumber and the product will get separated and deposited in rejection bin. Yet another embodiment of the present invention, a method wherein the variation of measured force beyond the set limit is due to low or high hardness value compared to specified value, or due to threaded length being out of the specified range. Still another embodiment of the present invention, a method wherein the reference value is obtained by taking values of 10 correct components. Yet another embodiment of the present invention, a method wherein the upper and the lower limits of rolling are set by trial and error method. Further embodiment of the present invention, a method wherein the displacement sensor gives an output of ±4V. Still another embodiment of the present invention, a method wherein force-distance relationship enables to discard bad parts that are out of specification before the commencement of rolling. Yet another embodiment of the present invention, a method wherein the tools are withdrawn on overload to prevent damage to the tools and the machine. Further embodiment of the present invention, a method wherein the combination of force and distance is used to segregate parts in manufacture to ensure zero defects. The invention is further explained in the form of following embodiments: Force amplifier: Force amplifier gives 0- 10 V output corresponding to the millivolt from the sensor. There are 3 stages of amplification available namely Low , Medium , and High. If the output signal in Low mode is X then in medium it will be 10 X and in high it will be 100 X. This amplification can be used depends on signal strength from force sensor. Work rest blade: Normally the work rest blade is set based on final size of the component after rolling. For example, if MIO thread to be formed on a blank, then initial blank diameter will be less than lOmm.This means that the centre line of the component will be below the centre line of the roll. Once the thread is completely formed, then the blank diameter will become close to 10 mm and the centre line of the MIO size thread will be in line with roll centerline. Man Machine Interface: This interface is a display unit, where operator can enter control parameters for rolling say force and distance directly. This unit will display reference distance, force values during 10-sample mode, mean load etc. Operator can observe through these readings by scrolling and can enter and set higher and lower limit of the force for rolling operation. Hence MMI interfaces operator directly with the logic controller. Force and Displacement sensors: There are force and displacement sensors mounted on the machine at a specific locations. The force sensor will send mV output to the amplifier during rolling operation where this signal voltage will be amplified to a measurable input and send to the CPU, while the displacement sensor will send voltage input to the CPU where there is a distance - voltage correlation exists. These two sensors have been integrated and the concept of monitoring the operation based on the logic provided to the CPU. FORCE SENSOR AMPLIFIER mV 0-IOV f CPU OK /NOT OK DISPLACEMENT -4V/ + 4V i i OUTPUT SENSOR AND AM PLIFIER Referencing valve: The referencing solenoid valve (1) of hydraulic system is energized and the fluid will pass through pressure reducing valve (14) at set flow rate. The flow rate is set based on rolling feed rate. Normally rolling feed rate is set to 0.076mm/roll rev. There is a knob in the flow control valve to set the flow. When the moving roll touches the component, slide stops and distance moved from home to part touch point is registered in MMI. Hydraulic system: The hydraulic system of the present invention having the following components: (a) single solenoid valve for referencing application (1); (b) solenoid valve for slide forward reverse application (2); (c) single solenoid valve for slide forward and reverse application (3); (d) single solenoid valve for rapid feed application (4); (e) single solenoid valve for slide return (5); (f) high response pressure switch for rapid to feed application (6); (g) single acting cylinder for slide actuation (7); (h) single solenoid for referencing (8); (i) low pressure high flow pump for rapid traverse (9); (j) high pressure low flow pump for feed (10); (k) low pressure relief valve (11); (1) high pressure relief valve for rolling operation (12); (m)pressure and temperature compensated flow control valve for feed regulation (13); and (n) pressure reducing valve for referencing (14); Single cycle operation of semi automatic mode: Roll start moving from home position at rapid feed. When the rolls touch the component the pressure develops and high-pressure low volume pump takes over the rolling operation. Complete rolling operation, slide reaches the forward position then returns to its home position at faster rate. Part ejects from the machine. This cycle will be used for 10-sample mode cycle in MMI. Once initial force setting is over, then machine will be switched over to MONITOR mode. Then selector will be put in Auto mode for continuous production. Matching of rolls: This is a very important procedure requiring great care and accuracy. The two dies are positioned, when rolling a standard screw thread, so that the crests of one die are exactly opposite the roots of the other at the point of rolling contact with the work piece. In order to establish this relationship a matching or roll-timing coupling has been provided whereby the drive shaft to the left-hand die spindle (fixed slide) is rotated independently of the moving slide die. This will position the dies in such a way that crest and root will be matched. The machine of the present invention can sense force variations due to defects and a laser sensor will scan the distance. This combination of the system with a central processing unit and MM! will ensure that parts delivered to accepted part will conform to specification and 100% defect free. Bad parts will get segregated providing scope for analysis and improvement. BRIEF DESCRIPTION OF THE ACCOMPANYING DRAWINGS Fig. 1 represents the placement of the part in the machine. Fig. 2 represents the monitoring system [Timing Sensor will be 'ON' during 'Cycle Start'. This is to switch on force amplifier] Fig. 3 represents the Block diagram for referencing Fig. 4 represents the block diagram for undersize/oversize elimination Fig. 5 represents the block diagram for low hard/high hard component elimination. Fig. 6 represents auto feeding and monitoring system Fig.7 represents hydraulic system Fig. 8 represents auto feeding and monitoring system - machinery device along with their linkages and its function Fig. 9 represents hierarchical functions hydraulic system Fig.lO represents engineering diagram of thread rolling machine The device is described hereafter with reference to the examples. The following examples are given by way of illustration and therefore should not be construed to limit the invention in any manner. Example 1 SCREEN SETTING FOR MAN MACHINE INTERFACE (MMH First Screen SYSTEM DEVELOPED BY SPM DIVISION SUNDRAM FASTENERS LIMITED PADI, CHENNAI NEXT Press NEXT Second Screen REFERENCE MODE UL REFERENCE DISTANCE: LL REFERENCE FORCE : SLIDE FORWARD REF SLIDE RET NEXT PRVS For referencing Press REF i Keep an OK component properly on work rest blade Turn on Hyd Press SLIDE FORWAR New reference d, stance will appear on the screen Press SLIDE REV T Do this operation for 2 or 3 times I Set UL, LL (initially feed component tolerance for UL - Upper Limit and LL - Lower Limit. In case more rejection and components are OK for gauge increase the limit) NEXT Press for next screen Third Screen Data 1 Data 2 Data 3 Data 4 Data 9 10 SAMPLES MODE Data 5 Data 6 Data 7 Data 8 Data 10 RESET PRVS NEXT Now keep selector switch in Semi auto mode. i Send 10 samples to roll 1 Now 10 readings (Force) will be available on this screen !_ Press NEXT for next screen RESET i is to reset all values in case of next job change. RESET will work only in Manual mode, also selector should be in 'Roll On', 'Hyd On', 'Coolant On' position. Note: All 10 'Samples' should be thoroughly inspected before going for auto cycle. In case any problem in rolling reset whole values and redo the exercise. Fourth Screen FORCE LIMIT MODE UL: TOUCH MEAN PEAK LOAD : LOAD LL: ACTUAL PEAK LOAD : Mean Peak Load Force 1+ Force 2 Force 10 10 (From 10 samples mode) : This value will automatically memorized. CAUTION! : Auto Cycle will not start without mean peak load. Ensure that mean peak load is appearing on 'Force Limit Mode' Screen. An Error message will be displayed, in case mean peak load is zero. 'Go through' 10 samples force received. 1 Find upper force and lower force 1 Add #10 with upper force and subtract #10 from lower force. i Set these values as UL and LL. In case more projections and if those components are OK to gauge and other quality terms are met, increase the limit in increment of #10. Press NEXT For next screen. PRVS Press for previous screen. 5"' Screen CNTR RESET M/C RUNNING MODE HOME DISTANCE HOME FORCE PEAK LOAD HOME PRVS COUNTER NOTE When machine is in normal running condition, ensure that MMI is in 'M/C RUNNING MODE'. Operator need not set anything in this mode. -^ HOME DISTANCE is the current distance when slide is in Home Position -> HOME FORCE is the current force when slide is in Home Position (normally zero) -> PEAK LOAD is the load generated during each and every rolling cycle. COUNTER is the number of pieces produced. CNTR RESET To reset the counter before going for next job change, press CNTR RESET Conditions for CNTR RESET I> Selector should be in manual mode 2> Turn on 'Roll On' 'Hyd On' and 'Coolant On' 3> Reset in 10 Samples mode (all values should be zero) 4> Then Press CNTR RESET EXAMPLE 2 MACHINE SETTING SET THE MACHINE FOR A PARTICULAR COMPONENT KEEP SELECTOR IN MANUAL MODE GOTO 'REFERENCE MODE' IN MMI KEEP A COMPONENT (MEASURE DIA OF THE COMPONENT AND CONFIRM THE TOLERANCE REFERENCING MODE TURN ON HYD, PRESS 'REF' & 'FWD' BUTTON IN MMI REFERENCE VALUE WILL NOW APPEAR IN MMI REPEAT THIS FOR 3-4 TIMES AND ENSURE THAT SAME READING OBTAINS IN MMI NOW SET TOLERANCE FOR SI7F VARIATION COME OUT FROM 'REF MODE' AND GOTO 10 SAMPLES MODE IN MMI RESET THE PREVIOUS FORCE KEEP SELECTOR IN SEMI AUTO MODE TURN ON 'ROLL ON' 'HYDON' & 'COOLANT ON' SELECTOR NOW SEND 10 SAMPLES TO ROLL AFTER 10 SAMPLES STOP THE CYCLE GO TO THE FORCE LIMIT MODE SET UPPER AND LOWER LIMIT FOR MEAN FORCE OBTAINED AUTO MODE GO TO M/C RUN-ING MODE IN MMI KEEP SELECTOR IN 'AUTO MODE' SET AUTO LOADER MACHINE AUTO START IN THIS MODE ONE CAN OBSERVE 1. PEAK LOAD DURING ROLLING 2. HOME DISTANCE 3. HOME FORCE 4. ERROR MESSAGE EXAMPLE 3 Component Dia rolling This distance can be set by Displacement sensor Generally displacement sensor will give an output of+/- 4V analogue output 6D±T. Tolerance V Set the reference distance by displacement sensor - i.e. OV at home. - Now initial distance with correct component is established. - Set tolerance of the component Vario sensor amplifier will give following output Set the initial ref. Force by using vario sensor i The o/p signal while slide touches the component. Set Reference distance with correct component This signal will compare With Reference distance This is mainly for under size/over size segregation V Send 10 samples to roll For setting upper and lower limit of force \f A wrong product where ODi>cDD PLC/micro- Slide moves forward and initial force signal develops before reference distance -> Product is oversize o/p from Processor to solenoid Undersize/-oversize V A wrong product where 4)D2«1>D Slide moves forward and initial force will not reach even after reference distance Product is undersize o/p from PLC/ Microprocessor to solenoid i Rolling Cycle Scanning of rolling force with respect to distance moved through out the rolling cycle r Set force reaches before target distance High hardness of product, o/p to solenoid Hardness segregation I Set force doesn't Reach even after target distance Low hardness of product, o/p to solenoid V EXAMPLE 4 Eliminating rolling undersize/oversize components: 1. take reference diameter to be rolled. 2. OD is the rolling diameter with tolerance and X is the reference distance. 3. depending upon component tolerance, the reference distance will vary from x +A X to X -A X where A x is the component tolerance, and 4. set minimum force signal at x+AxtoxAx THROUGH MMI 5. if force signal reaches below X-Ax or above x+Ax it indicates that the component is oversize/undersize. Hence the component will be rejected. EXAMPLE 5 Eliminating rolling of high hard / low hard components. 1. take rolling of 10 components is 'SEMI AUTO MODE' 2. the system will set the mean value of the rolling force obtained for the 10 components, and 3. set upper and lower limit of this mean value by trial and error method. ERROR MESSAGES 1. Component over size and Component under size 2. High hardness and Low hardness 3. Check touch sensor 4. Other failures due to limit switch. Proximity Switch, Motor OLR also will be displayed. CONDITIONS FOR RESET IN 10' SAMPLES MODE 1. Only when selector in manual mode 2. 'Roll ON', 'HYD ON' and 'Coolant ON' conditions CONDITIONS FOR REFERENCE MODE 1. Selector in manual mode 2. Ref Mode will be inactive in AUTO, SEMI AUTO MODE. This is an additional safety provided for auto cycle. CONDITIONS FOR AUTO CYCLE 1. Ejector should be in HOME position. 2. M/c slide in HOME position (through displacement sensor) 3. Home force should be ZERO 4. Component should be touched at touch sensor MEASUREMENT OF REFERENCE DISTANCE The Laser displacement sensor will give an output ranging from + 4 / - 4 V which corresponds to the linear distance of + 40 mm / - 40 mm. During referencing amount of voltage develops will be converted into linear distance. For example, if + 2V develops during referencing cycle indicates that slide has covered a distance of 20mm from its home position. EXAMPLE 6 The following case study has been done to assess the efficacy of the machine. Collar Bolts of the dimension M13 x 1.25 x 57 are used for rolling. Referencing cycle: Reference distance obtained Tolerance set Target force 5.22 = x (Fig 1) ±0.01 #30 It is observed that any component having reference distance 5.22 ± 0.01 is accepted for rolling, else the component is rejected and no rolling operation is performed for such components. It is also observed that any component having the reference distance less than 5.22 + 0.01, PLC does not receive target force within the reference band 5.22 ±0.01, hence the component is treated as oversize. It is also further observed that any component having the reference distance more than 5.22 + 0.01, PLC does not receive target force within the reference band 5.22 ± 0.01, hence the component is treated as undersize. During rolling operation soft components are rejected, wherein the force obtained while rolling operation is found to be less than lower limit of the force set. ADVANTAGES 1. In the present invention the variation in input material and under and over size of diameters of the blanic parts are eliminated before rolling through the application of force and displacement sensing. 2. The present invention also provides means for eliminating low and high hardness components before they are rolled by the application of force and displacement sensing. 3. In the present invention, the distance/force correlation eliminates any defective components entering or coming out of the machine, thereby ensuring zero defect rolling. WE CLAIM: 1. An automated thread rolling machine for eliminating rolling/working of undersize, low hardened and high hardened components and to obtain zero defect products said machine comprising: (a) a force sensor used in conjunction with a displacement sensor; (b) a force amplifier (c) a timing sensor (d) a movable slide with a rolling head having a thread rolling die; (e) a fixed slide with a rolling head having a thread rolling die; (f) a roll motor to start the rolls; (g) an end stopper with touch sensor to confirm the component; (h) the thread rolling dies are mounted on two shafts rotating in same direction; (i) a work rest blade; (j) a control system; (k) a man machine interface unit (MMI); (1) an ejector to eject components after rolling; (m)a cycle start button to start the process cycle; (n) a dumper; (o) a hydraulic motor; (p) a hydraulic system; (q) an auto feeder unit and (r) a collection bin. 2. The machine according to claim 1, wherein the force sensor is a quartz crystal that develops a potential difference when subjected to pressure. 3. The machine according to claim 1, wherein the force sensor generates a potential difference of 0 to 1OV when subjected to pressure. 4. The machine according to claim 1, wherein the force sensor verifies the correctness of the parts by ensuring the correct dimensions of the parts. 5. The machine according to claim 1, the displacement sensor is a laser sensor. 6. The machine according to claim 1, wherein the displacement sensor gives an output of ± 4V corresponding to the linear distance of ±40 mm covered by the slide. 7. The machine according to claim 1, wherein the displacement sensor will scan the moving slide through out the movement and also ensures constant stopping position at the end of the travel of the slide. 8. The machine according to claim 1, wherein the force amplifier is an electronic unit, which amplifies mill volts, received from force sensor to a measurable voltage. 9. The machine according to claim 1, wherein the timing sensor is used to regulate the force amplifier. 10. The machine according to claim 1, wherein the timing sensor is a proximity switch, which will be switched ON during rolling to provide an electric signal voltage to force amplifier and switches OFF to reset the amplifier. 11. The machine according to claim 1, wherein the movable slide having the rotating thread rolling die moves from the rest position to the location of the part. 12. The machine according to claim 1, wherein the fixed slide having the rotating thread rolling die. 13. The machine according to claim 1, wherein the fixed and movable rolls consist of multi start thread profile. 14. The machine according to claim 1, wherein the rolling dies are driven by the roll motor and move at a constant speed. 15. The machine according to claim 1, wherein the end stopper with touch sensor housed in it confirms the component and permits the slide to move forward for rolling operation. 16. The machine according to claim 1, wherein the rotation of the shaft is from a motor. 17. The machine according to claim 1, wherein the shafts are supported by suitable bearings. 18. The machine according to claim 1, wherein two thread rolling dies are mounted on each shaft. 19. The machine according to claim 1, wherein the work rest blade in positioned to ensure that the centre of the part will be same as roll center after rolling. 20. The machine according to claim 1, wherein the control system receives signals from the sensors, compare it with a predetermined value and sends command to machine elements to perform task based upon the sensed signal. 21. The machine according to claim 1, wherein the control system is a programmable Logic Controller consisting of a processing unit, input/output modules. 22. The machine according to claim 1, wherein the input/output modules of said control system is selected from digital and analogue systems. 23. The machine according to claim 1, wherein the Man Machine Interface Unit (MMI) provides interface between operator and the Control System. 24. The machine according to claim 1, wherein the Man Machine Interface Unit (MMI) is used for entering control parameters selected from force and distance directly. 25. The machine according to claim 1, wherein Man Machine Interface Unit (MMI) displays reference distance, force values during 10 sample mode and load values generated during each rolling cycle. 26. The machine according to claim 1, wherein the Man Machine Interface Unit (MMI) provides means for assessing the samples before the machine enters the auto mode. 27. The machine according to claim 1, wherein the ejection mechanism with touch sensor is used for product confirmation and to eject the part of the machine as per confirmation signal received from Displacement sensor. 28. The machine according to claim 1, wherein the dumper segregates good and bad parts at the delivery end, based on the signal received from Control System. 29. The machine according to claim 1, wherein the component to be rolled fed by means of an automatic feeding loading device. 30. The machine according to claim 1, wherein the collection bin is used to collect the threaded parts. 31. The machine according to clam I, wherein the combination of force and distance references is used to segregate parts during the manufacture and to ensure zero defect. 32. The machine according to claim 1, wherein a consistent thread dimensions of the parts are obtained as the distance sensor ensures that the rolls reach a constant position at the end of the operation by comparing the distance moved with the pre¬determined position. 33. The machine according to claim 1, wherein said machine is used to check die wear and die chipping. 34. The machine according to claim 1, wherein said machine is used to check run up, pull down parts, incorrect parts of length, bent parts and under size/over size parts. 35. The machine according to claim 1, wherein said machine is used for any manufacturing device wherever force/displacement co-relation exists, more preferably for circular thread rollers. 36. The machine according to claim 1, wherein pressure is set in the range of 6-8 bar to prevent the roll from creating an impression on the parts. 37. A method of eliminating rolling/working of undersize and low hardened/high hardened components with an automated thread rolling machine, said method comprising the steps of: (a) assembling the rolls; (b) switching on the roll motor to enable rolls to rotate in the desired direction; (c) switching on the hydraulic motor; (d) feeding parts on to the work rest blade; (e) moving the slide and contacting the tip of the part with the end stopper which has a touch sensor housed in it to send a signal to CPU, which in turn sends signal to the hydraulic system for starting a new cycle; (f) measuring the reference distance from distance between the moving slide and the part with correct size and storing in the Man Machine Interface(MMI); (g) measuring average force in semi auto mode; (h) switching on the cycle start button to start the moving roll; (i) advancing the roll to contact the part; (j) tracking the distance by the distance sensor at which the rolls contact the part and transmitting to the CPU; (k) comparing with the reference distance as stored in MMI; (1) sensing the touch force and transmitting the signals to CPU where they will be compared with a pre-determined reference distance to verify the correctness of the blank size; (m)ejecting the suspect part out and separating at dumper box and transferred to rejected bin automatically; and (n) moving forward the rolls to carry out thread rolling operation to obtain zero defect threaded products. 38. The method according to claim 37, wherein the rolls are assembled to ensure matching by positioning the two dies so that the crests of one die are exactly opposite the roots of the other at the point of rolling contact with the work piece. 39. The method according to claim 37, wherein the matching of the two dies is ensured by positioning the dies in such a way that crest and root of the threads are matched. 40. The method according to claim 37, wherein the desired direction of the rolls depends on the type of thread to be rolled on blank, which is selected from Left thread or Right thread. 41. The method according to claim 37, wherein the component is fed by means of an automatic bolt loading device. 42. The method according to claim 37, wherein in step semi auto mode is used during initial setting of the machine to perform a single cycle of operation. 43. The method according to claim 37, wherein the distance sensor will scan the slide through out the movement of the slide during the operation. 44. The method according to claim 37, wherein the distance sensor will ensure that the rolls reach a constant position at the end of the operation by comparing the distance moved with the pre-determined position, thus ensuring constant minor diameter of the product, which is an indicator of consistent thread dimensions. 45. The method according to claim 37, wherein when the force-measuring sensor feels force value beyond set limit, a signal is sent to dumber and the product will get separated and deposited in rejection bin, 46. The method according to claim 37, wherein variation of measured force beyond the set limit is due to low or high hardness value compared to specified value, or due to threaded length being out of the specified range. 47. The method according to claim 37, wherein the reference value is obtained by taking values of 10 correct components. 48. The method according to claim 37, wherein the upper and the lower limits of rolling are set by trial and error method. 49. The method according to claim 37, wherein the displacement sensor gives an output of 50. The method according to claim 37, wherein force-distance relationship enables to discard bad parts that are out of specification before the commencement of rolling. 51. The method according to claim 37, wherein the tools are withdrawn on overload to prevent damage to the tools and the machine. 52. The method according to claim 37, wherein the combination of force and distance is used to segregate parts in manufacture to ensure zero defects. 53. An automated thread rolling machine for eliminating rolling/working of undersize substantially as herein described and illustrated. 54. A method of eliminating rolling/working of undersize substantially as herein described and illustrated.

Documents:

0284-mas-2001 abstract duplicate.pdf

0284-mas-2001 abstract.pdf

0284-mas-2001 claims duplicate.pdf

0284-mas-2001 claims.pdf

0284-mas-2001 correspondence others.pdf

0284-mas-2001 correspondence po.pdf

0284-mas-2001 description (complete) duplicate.pdf

0284-mas-2001 description (complete).pdf

0284-mas-2001 description (provisional).pdf

0284-mas-2001 drawings.pdf

0284-mas-2001 form-1.pdf

0284-mas-2001 form-18.pdf

0284-mas-2001 form-26.pdf

0284-mas-2001 form-3.pdf

0284-mas-2001 form-5.pdf

0284-mas-2001 petition.pdf