Title of Invention

IMPROVEMENT IN DIMENSION OR DEPTH CONTROL SYSTEM IN A MACHINE

Abstract

The present invention relates to improvement in dimension / depth control system used in a machine, more particularly it relates to automatic dimension / depth control for operations like drilling, tapping, reaming, boring on radial drilling or other conventional machine(s). Dated this 26TH day of JULY 2005 MAHINDRA & MAHINDRA LTD. BY THEIR ADVOCATES-IP TO THE CONTROLLER OF PATENTS THE PATENT OFFICE, MUMBAI 26 JUL 2005

Full Text

FORM 2 THE PATENTS ACT, 1970 [39 OF 1970] COMPLETE SPECIFICATION [SEE SECTION 10 & RULE 13] 1 TITLE Improvement in Dimension /Depth control system on a machine 2 APPLICANT NAME MAHINDRA & MAHINDRA LTD. ADDRESS 1, GATEWAY BUILDING, APOLLO BUNDER, MUMBAI 400001 NATIONALITY INDIA The following specification particularly describes the nature of the invention and the manner in which it is to be performed:- Field of the Invention The present invention relates to improvement in dimension / depth control system used on a machine, more particularly it relates to automatic dimension / depth control for operations like drilling, tapping, reaming, boring on radial drilling or other conventional machine(s). Provision of an additional automatic control system in existing conventional machine configuration allows operational flexibility in terms of various depths, dimensions, sizes, and types of operation on same machine with improved dimensional accuracy. Background of the Invention Various machines such as Radial Drilling Machines, Milling Machines, Special Purpose Machines, Computerized Numerical Control (CNC) machines are being used for 'manufacturing industrial components. Selection from above machines is purely based on quality and cost requirement. Conventional drilling, milling or other machines are more popular for manufacturing industrial components / parts because of their cost advantage. Machining with conventional machines always requires special attention / checkpoint once the operation is completed. In current manufacturing practices 100% inspection / checking is carried out after completion of these drilling, tapping, reaming, boring or alike operations on conventional machine(s). Such inspection for each and every component is very tedious, time consuming and expensive. Also these exercises are neither foolproof nor having positive controls on various dimensions / depths control because of the reliance on pure manual controls. Examples of the related patents in this area are explained below. US Patent No:-5328303, Dated 12,1994 According to this invention by using worm and worm wheel and braking mechanism a mechanical control system is provided. The power corresponding to revolution speed reduction is converted in to elevating or lowering the spindle automatically. 2 2 6 JUL 2005 This concept cannot be easily implementable in conventional machines, as it requires major modifications in machine spindle and head assembly. Because of worm and worm arrangement, such machines are restricted for high-speed operation, hence not suitable for mass production. • US Patent No.-5857814, dated 07,1999 In this patent a sensor is used for sensing the revolution of spindle and also another sensor for sensing vertical traveling of the spindle. An electronic brake is used to control the movement by means of micro controller. Vertical distance traveled by the spindle is controlled by controlling current flowing through electronic brake. The mechanism involved worm and worm wheel arrangement for moving tool holder up and down. This concept is not easily implementable in conventional machines, as it requires major modifications in machine spindle and head assembly. • US Patent No.-4985841, dated 15,1991 According to this patent a Servomotor with servodrive and position controller is used for controlling the depth. This concept is similar to computerized numerical control (CNC) machines, wherein spindle rotation and axial motion are synchronized for rigid tapping. In this case speed command is coming from position controller. In conventional radial machines induction motor is use and hence to employ the above concept major mechanical as well as electrical modifications will be required. • US Patent NO.-4831364, dated 05,1989 According to this invention a drive motor current is sensed by using the meter-relay. The value during no load current is sensed and stored meter -relay. This value is compared with the current during the drilling operation and time is measured from the instance of current rises from the no load to the instance when current comes back to the no load value. This time is corresponding to the distance traveled. This method has got many limitations like the value of current will be fluctuating and hence can't be set precisely. Conceptually this invention distinguishes from the present invention. 3 26 JUL 2005 Therefore it is the requirement of control system to be adopted in the conventional machine(s) for automatic controlling of various dimensions / depths of drilling, tapping, milling, boring or alike operations irrespective of number of operations, their dimensional requirements and components design with least modifications in the existing machine configuration. Thus adaptation of invented automatic dimension / depth control system eliminates the requirement of 100% inspection thereby minimizing operational time and cost, improves machining accuracy and reduces rejection / wastage. Summary of the Invention It is the primary objective of the present invention to provide control system on conventional machine(s) like Radial Drilling, Tapping machine or other similar type of conventional machine(s), which will automatically control various machining dimensions / depths during operation. It is another object of the present invention to provide foolproof method / system for various dimensions / depths control, which will improve machining productivity, machining cost along with operational accuracy. It is another object of the present invention to provide a control system in existing conventional machines, which is enough flexible to work on various industrial components / parts design irrespective of number of operations and their dimensional requirements with least modifications. Brief description of the drawings Figure 1 shows the Isometric view of at last one of the conventional machine (Radial drilling machine) widely used for manufacturing various industrial parts / components. Figure 2 shows the schematic view of automatic control system adopted in the conventional machine as illustrated in figure 1. Figure 3 shows the Isometric view of another conventional machine (Tapping machine) widely used for manufacturing various industrial parts / components. 5 26 JUL 2005 Figure 4 shows the schematic view of automatic control system adopted in conventional machine as illustrated in figure 3. Detailed Description of Preferred Embodiments Referring to the figure 1, which shows the isometric view of at least one of the conventional (Radial Drilling machine) machine (1). The machine (1) has a moving head assembly (2), which is having tool-holding mechanism (3). The part to be machined (tapping, drilling, reaming, boring) is placed on a machine base (4) below the head assembly (2). The head assembly (2) moves by rotating hand wheel provided on it. In the present invention the non-conductive plate(s) (6) of material like Bakelite, Teflon is fixed on the machine base plate (4) in order to isolate the machine base plate electrically from the workpiece (7). Again on this non-conductive plate(s) (6) an additional electrical conductive plate(s) (8) of stainless steel, copper, aluminum or alike material is fixed, on which the workpiece (7) is to be rested. This stainless steel plate(s) (8) is connected to an electronic controller (9) by means of wire(s) (10) and the wiring connections are so made that the wire(s) (10) does not interfere with the workpiece (7) during loading / unloading process. According to the above arrangement the workpiece (7) is totally isolated from the machine body (1). Low voltage of about 12v is given to machine head assembly (2), which is from machine (1) electric supply system . Since the complete head assembly (2) is made up of metal, it conducts. Also when the workpiece (7) is placed on conductive plate(s) (8), the wire (10) attached to it will get 12v through the workpiece (7), as soon as the cutting tool (s) (11) touches the workpiece (7). This low voltage current is used to command the electronic controller (9) about starting point of the operation. The reference for dimension / depth measurement is established from the point of contact (20). Counter weight(s) (12) is provided for counter balancing machine head assembly (2) by using chain (13) and the guide arm (14). When the machine head assembly (2) moves downwards the counter weight(s) (12) moves upward in the same proportion. This movement of counter weight(s) (12) is transmitted to the Encoder (Linear or Rotary) (15) by means of the suitable arrangement shown in the figure 2. In this arrangement an 6 26 JUL 2005 additional shaft (16) is provided, which is supported at it's both the ends (17) with counter weight pulley (14) at its center. The rotary movement of this shaft (16) is transferred to the encoder (15) by providing a flexible coupling (19) in-between shaft (16) and Encoder (15). The electronic output of an Encoder (15), which is in the form of electronic pulses is given to the Electronic Controller (9) fitted anywhere on the machine body (1). The controller then counts number of pulses using micro-controller based circuitry. The micro-controller is programmed in assembly language to count the pulses. These pulses counted are converted to the distance travelled by means of the conversion ratio already fed into the program. This conversion ratio is actually calculated on the machine by measuring the physical distance travelled by the cutting tool (11) from the reference point (20) and equivalent displacement indicated by the Electronic Controller (9). These pulses are directly proportionate to the vertical distance travelled by the counter weight (s) (12) and hence by the tool holder (3) / cutting tool (11). The Encoder (15) generates electronic pulses, when machine head assembly (2) moves in upward and downward direction. The pulses, generated when machine head assembly moves in downward direction after the reference point(20) are to be counted by the Electronic controller (9). This discrimination is made in the electronic controller (9) through software code. The converted distance is compared against the set value (set by user / operator prior to new machining set up) for the respective tool(s) (11). As the tool (11) travels downward with every unit distance travelled by the machine head assembly (2), the display value on the electronic controller (9) reduces by a one unit. Now after conclusion of machining operation, if operator withdraws the cutting tool (11), then the point at which metal contact breaks (low voltage signal) the electronic controller (9) will check/verify whether the actual tool travel is equal to the set value (set by user / operator prior to new machining set up). If it is not so then the Electronic Controller (9) will display an error which error is conveyed to the operator in audio / visual form by means of hooter / lamps etc. (21) provided anywhere on the machine. As an additional feature, provision can be made to forward this error to any machine components like machine contactor (not shown), for discontinuing machining operation. 7 26 JUL 2005 In order to facilitate various operations of more than one dimension the provision of different settings for individual operation is made in the present invention. For this user / operator should go in setting mode by pressing the SET mode key (22) provided on the controller (9). With this set key (22) pressed for predetermined time, the controller (9) shows - - on display. Once again the set key (22) is to be pressed and then P_0 will be displayed on display (23). On pressing the set key once again the dimension set for the first tool (II) will be displayed. This dimension can further incremented or decremented by using Increment key (24) or Decrement key (25) in the desired range (unit). The required value is set after the set key (22) is pressed once again to set the required dimension in the controller memory. The value stored in this way will be stored in the EEPROM (Electrically Erasable Programmable Read Only Memory) section of Microcontroller and will be retained even after any power shutdown. Hence the user doesn't need to set specified dimensions every time after power shutdown. When required dimension for all cutting tools (II) are set then user must press the reset button (26) in order to come out from the setting mode. In the present invention there is a scope for counting number of machined holes during machining of workpiece (7). For this the workpiece (7) loading / unloading feedback is given to the Electronic Controller (9) through limit switch (27). After workpiece (7) loading input is received by the electronic controller, the number of holes machined according to their specifications are counted and compared with the set value (set by user / operator prior to new machining set up). If number of operations is found to be less than the set value then after unloading the workpiece (7), the Electronic controller will display an error and this error is conveyed to the operator in audio / visual form by means of hooter / lamps etc. (21) provided anywhere on the machine body (1). In the present invention the automation changeover for various cutting tools (11) is achieved by modifying tool storage / holding arrangement (28). As shown in figure 2 low voltage signal is given to the cutting tool holder(s) (29). The signal is given to the electronic controller (9) if the tool (11) is available in the respective pocket(s) (30) of tool holder(s) (29). Since the tools (11) are made up of metal, they conduct electricity and complete the circuit path, on the other hand signal will break if the cutting tool is missing 8 26 JUL 2005 (not available) from the tool holder pocket (30). This arrangement facilitates the electronic controller (9) to select specified dimension for the specific cutting tool, which is missing from tool holder(s) pocket. If more than one cutting tool is missing then the electronic controller (9) will trigger the missing alarm for indicating the same. In the present invention an additional care is taken to avoid the false triggering of an alarm when operator tries to locate cutting tool(s) (11). Since during this operation there may be several makes and breaks of contact with the workpiece (7), because of which there is a possibility of wrong alarm triggering. To avoid this tolerance (travel distance) is set in electronic controller (9). The electronic controller (9) does not trigger alarm if the cutting tool (11) is withdrawn within this set tolerance which is from workpiece reference (20). Also the Controller (9) is programmed for continuous measurement of cutting tool travel in workpiece, inspite of several makes and brakes of cutting tool (11) and workepiece (7).Another embodiment of the present invention is explained with reference to the figures 3 and 4, wherein tapping machine is taken as a reference. The basic elements of dimension / depth control system described in above paragraphs for radial drilling machine remains the same, whereas the mechanical arrangement for transmitting cutting tool (11)/ tool holder (3) travel to the encoder (15) will be changed according to the construction and location of various machine components. As show in figure 4 the vertical movement of the tool holder (3) is transmitted to rotary encoder (15) by means of suitable arrangement in between tool holder (3) and encoder (15). This suitable arrangement may consist of shaft (16), shaft supports (17), chain drive (13) and (14). The said shaft (16) driven by tool holder (3) and further transmits drive to an encoder (15) through chain drive (13) and (14) provided at the end of machine head (2). While the above description herein described constitutes a preferred embodiment of this invention, it is to be understood that the invention is not limited to this precise form, and that changes may be made therein without departing from the scope of the invention which is defined in the appended claims. 9 2 6 JUL 2005 We Claim :- 1. An improved dimensional / depth control system on a machine comprising :- a) Machine body (1), b) Non-conductive plate(s) (6) of Bakelite, Teflon or other similar type of material, c) Conductive plate(s) (8) of stainless steel, copper, aluminum or other similar type of material, d) Mechanical arrangement for transferring cutting tool (11) and / or tool holder (3) traveling distance to an Encoder (15), e) Said Encoder (linear or rotary) to count said cutting tool travel distance, f) An Electronic controller (9), g) An audio and / or visual means (21), h) Machine contactor or like machine components, i) An electrical cables / wires (10) for necessary electronic connection of said dimensional / depth control system. 2. A system as claimed in claim one wherein, a) Said machine body is preferably metallic body and is a part of conventional machine like Radial Drilling, Tapping or other similar type of machines, b) Said non-conductive plate is. provided on a machine base plate (4) and in-between said base plate and said conductive plate, c) Said conductive plate(s) is fixed on to the said non-conductive plate(s) on which workpiece (7) is to be located for machining, d) Distance traveled by said cutting tool is transferred to said encoder located anywhere on said machine body by means of said mechanical arrangement, e) Output of said encoder, which is in the form of electronic pulses, is given to said electronic controller, which is also located anywhere on said machine body, f) Said conductive plate(s), encoder, electronic controller, audio / visual means and machine contactor are connected to each other by means of said electric cables / wires, g) In case of malfunctioning or non-conformity during the intended operation on the said workpiece / component(s), said electronic controller displays an errors, which 10 2 6 JUL 2005 is then transmitted to said audio and / or visual means or any machine component like said machine contactor for discontinuing machining operation. 3. Said mechanical arrangement as set forth in claim 1 and 2 for Radial drilling machine can be comprising: a) Counter weights (12) provided for the balancing of said tool holder and moves depending upon said tool holder / cutting tool travels, b) A chain(s) or linkage(s) (13) to link said counter weights and said tool holder, c) Said chain rolls over a sprocket(s) (14), d) Said sprocket is located on a shaft (16), supported with suitable arrangement at its both the ends (17) on said machine body, e) One end of said shaft is coupled to said encoder by means of a coupling (19) in-between said shaft and encoder, h) An electronic controller as set forth in claim 1 and 2 gets inputs from said cutting tool, said workpiece, said encoder, said conductive plate(s) and after processing said inputs generates an output in the form an electronic errors, in case of any abnormality / malfunctioning occurred during machining of said workpiece / component(s), said electronic error is then transferred to said audio and / or visual means or any machine component like said machine contactor for discontinuing machining operation. 4. An improved dimension / depth control system in a machine comprising of: a) Machine body (1), b) Non-conductive plate(s) (6) of Bakelite, Teflon or other similar type of material, c) Conductive plate(s) (8) of stainless steel, copper, aluminum or other similar type ofmaterial, d) Mechanical arrangement for transferring cutting tool travel (11) to an Encoder (15), e) Said Encoder (linear or rotary) to count said cutting tool traveling distance, f) An Electronic controller (9), 11 26 JUL 2005 g) An audio and / or visual means (21), j) Machine contactor or like machine components, h) Cutting tool fixture (28), i) Cutting tool holders (29), j) Variety of cutting tools (11), k) Contact sensor(s) (27), k) Electronic cables / wires (10) for necessary connection of said dimensional / depth control system. 5. An improved dimension / depth control system as set forth in claim 4 wherein, a) Said machine body is preferably metallic body and is a part of conventional machine like Radial Drilling, Milling or other similar type of machines, b) Said non-conductive plate is provided on the base plate (4) and in-between said base plate and said conductive plate, c) Said conductive plate is fixed on to the said non-conductive plate on which workpiece (7) is to be located for machining, d) Distance traveled by said cutting tool is transferred to said Encoder fixed anywhere on said machine body by means of said mechanical arrangement, e) Output of said encoder, which is in the form of electronic pulses, is given to said electronic controller, which is also located anywhere on said machine body, f) Said cutting tool fixture located near by said machine body for holding said cutting tools required for intended machining of said workpiece / machine component(s), g) Said tool holder are formed in cutting tool fixture to store said cutting tools when not in use, h) Said contact sensor is located on said conductive plate(s), i) Said conductive plate(s), said Encoder, said Electronic controller, said audio and / or visual means, said machine contactor, said cutting tool fixture, said cutting tool holders, said contact sensor are connected to each other by means of said electronic cables / wires, 12 26 JUL 2005 i) In case of malfunctioning or non-conformity during the intended operation on the said workpiece / component said Electronic controller displays an electronic errors, which is then transmitted to said audio and / or visual means or any machine component like said machine contactor for discontinuing machining operation. 6) An electronic controller as set forth in claim 5 and 6 gets inputs from said cutting tool, said workpiece, said encoder, said conductive plate(s), said cutting tool fixture, said tool holders, said contact sensor and after processing said inputs generates an output in the form of said electronic errors, in case of any abnormality / malfunctioning occurred during machining of said workpiece / component, said electronic error is then transferred to said audio and / or visual means or any machine component like said machine contactor for discontinuing machining operation. Dated this 26TH day of JULY 2005 MAHINDRA & MAHINDRA LTD. BY THEIR ADVOCATES-IP TO THE CONTROLLER OF PATENTS THE PATENT OFFICE, MUMBAI 13 26 JUL 2005

Documents:

886-mum-2005-abstract(26-7-2005).doc

886-mum-2005-abstract(26-7-2005).pdf

886-mum-2005-claims(26-7-2005).doc

886-mum-2005-claims(26-7-2005).pdf

886-MUM-2005-CLAIMS(AMENDED)-(22-8-2012).pdf

886-MUM-2005-CLAIMS(AMENDED)-(30-6-2011).pdf

886-MUM-2005-CORRESPONDENCE(13-4-2009).pdf

886-mum-2005-correspondence(20-10-2007).pdf

886-MUM-2005-CORRESPONDENCE(22-3-2012)-.pdf

886-MUM-2005-CORRESPONDENCE(22-3-2012).pdf

886-MUM-2005-CORRESPONDENCE(24-4-2012).pdf

886-mum-2005-description(complete)-(26-7-2005).pdf

886-MUM-2005-DRAWING(22-8-2012).pdf

886-mum-2005-drawing(26-7-2005).pdf

886-MUM-2005-DRAWING(30-6-2011).pdf

886-mum-2005-form 1(26-7-2005).pdf

886-MUM-2005-FORM 13(22-3-2012).pdf

886-MUM-2005-FORM 18(13-4-2009).pdf

886-mum-2005-form 2(26-7-2005).doc

886-mum-2005-form 2(26-7-2005).pdf

886-mum-2005-form 2(title page)-(26-7-2005).pdf

886-MUM-2005-FORM 2(TITLE PAGE)-(30-6-2011).pdf

886-mum-2005-form 26(26-7-2005).pdf

886-mum-2005-form 3(26-7-2005).pdf

886-mum-2005-form 5(26-7-2005).pdf

886-MUM-2005-MARKED COPY(22-8-2012).pdf

886-MUM-2005-REPLY TO EXAMINATION REPORT(30-6-2011).pdf

886-MUM-2005-REPLY TO HEARING(22-8-2012).pdf

886-MUM-2005-SPECIFICATION(AMENDED)-(22-8-2012).pdf

886-MUM-2005-SPECIFICATION(AMENDED)-(30-6-2011).pdf