CA1290840C

CA1290840C - Tool identification system

Info

Publication number: CA1290840C
Application number: CA000526130A
Authority: CA
Inventors: Richard O. Juengel
Original assignee: GTE Valeron Corp
Current assignee: Valenite LLC
Priority date: 1985-12-30
Filing date: 1986-12-23
Publication date: 1991-10-15
Anticipated expiration: 2008-10-15
Also published as: EP0230642A3; JPS62181857A; EP0230642B1; US4742470A; DE3683030D1; EP0230642A2; JPH0671344B2; ES2027956T3

Abstract

TOOL IDENTIFICATION SYSTEM

ABSTRACT OF THE DISCLOSURE
Provision is made for identifying tools used in an automated machine tool system. A module or transponder is mounted to the tool and interrogated by a transceiver which, in the preferred embodiments, has read/write capabilities.
The transponder uses energy from the transmitted signal to power itself and send information stored in its memory back to the transceiver. In one embodiment, electromagnetic energy is transmitted from the transceiver to the transponder while the transponder to transceiver communication link is provided by way of capacitive coupling. In another embodiment data is communicated bi-directional through modulated optical signals while power to the transponder is sent from the transceiver through an electromagnetic coupling.

Description

TOOL_IDENTIFICATION ~Y.STEM

Field of the Invention This invention relates generally to identification devices and, more particularly, to devices ~or identifying tools used in automated machine tool systems.

BacXaround of the Invention In order to perform the. variety of machining operations required to be per~ormed on a workpiece the computer numerically controlled (CNC) machine has access to I a tool storage magazine containing the required tools. All of these tools are mounted on an industry standard shanX
wXich can he placed in the machine ~pindle automatically by ; the machine.

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This diversity of tooling allows the machine to be programmed to produce a very wide variety of parts, or very complex parts without any need for machine operator intervention.

A further improvement o~ such a manufacturing concept is the Flexible Manufacturing System (FMS). In such an application a cell consists of several unmanned machines. In this application, not only can the machines selQct their own tools, but the machines can exchange or share tools between themselves.

As is well known, cutting tools have a finite life span after which they must be reconditioned. Thus, it would be desirable to know the amount of use each tool has received.

Further, even after reconditioning, a tool, though perfectly suited for a particular operation, may not be of an optimum dimension for which a machine is programmed thus requiring an offset.

In such a situation it would be desirable for the machine receiving a particular tool to be able to positively identify it as a modified correct tool for the operation to be performed whereby the machine can itself provide the required offset.

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~ 2~ arl) Summarv oE the Invention The present invention provides a more fle~ible and economically efficient improvement over currently known tool control arrangements.
It provides the ability to locate data indicative of a tool's identity, type, size of offset and condition with a particular tool, which can then be read and transmitted to a data receiving device.
The present invention provides an electronic implant within the cutting tool for storing the pertinent data and which requires no co-located batteries for its operation.
The present invention includes an implant in the form o~ a transponder which is mounted to the tool. The transponder is adapted to wirelessly transmit an identification associated with the tool to a remote device whereby characteristics of the tool can be interrogated prior to beginning operations on the workpiece.
In its method aspect the invention relates to a method comprising: mounting a transponder in a tool, the transponder including a read/write memory having a unique identification code stored therein; placing the tool in a temporary storage device; electromagnetically transmitting sufficient power and data from a transceiver to the transponder to power and read the memory; electrostatically transmitting the identification code to the transceiver;
comparing the identification code with preselected information; and loading the tool into a machine for per~orming operations on a workpiece as a result of the comparison.
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A particularly advantageous design is disclosed in connection with one embodiment of this invention that also finds broad utility even outside the machine tool environment.
Brie~ly, the identification system includes a transceiver having first means for transmitting an electromagnetic signal and second means for receiving an electrostatic signal. A
transponder includes a memory and ~irst means for receiving the electromagnetic signal from the transceiver. The electromagnetic signal is th~n used to supply power to the memory. The transponder also includes second means that is ~apacitively coupled to the ~econd means in the transceiver.
The second means in the transponder is used to transmit an electrostatic signal associated with information stored in the memory back to the transceiver.

Descri~tion of the Drawin~

These and other objects and features of the invention will become apparent from a reading of the detailed description of a preferred embodiment taken in conjunction with the drawings comprising:

Fig. 1 is a block diagram showing a tool having a memory implant and a number of control devices chained together for connection to a master processor.

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~ ~9~4C) Fig. 2 is a simplified schamatic of an individual control device.

FigO 3 is a schematic of the circuit of the memory implant that is located in the machine tool.

Fig. 4 is a plan view of the memory implant.

~ ig. 5 is a side sectional view of the memory implant.

Fig, 6 is a plan view of the Read/Write head.

Figure 7 is a view which shows a typical machine tool environment in which the present invent~on finds particular utili~y.

F.igur~ 8 is a side view of a tool including an adapter portion and a bit, with the module or transponder being shown mounted within the drive key of the adapter.

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Figure 9 is a cross-sectional view of a transceiver or read~write head made in accordance with the teachings of one embodiment of this invention.

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4~) Figure 10 is a side cross-sectional view of the implanted module or transponder made in accordance with the teachings of one embodiment of this invention.

Figure 11 is a generali~ed block diagram illustrating the functions carried out by the transceiver and transponder according to the broad teachings o~ the present invention.

Figure 12 is a block diagram of the electrical circuitry of the transceiver and transponder made in accordance with one embodiment of this invention.

Figure 13 is a detailed schematic diagram o the tran ponder circuitry made in accordance with one embodiment of this invention.
' Figure 14 comprises a series of waveforms helpful in understanding the decoding function in the transponder.

Description of the Preferred Embodiment In order to better gain an understanding of the invention, the basic components o~ the invention and their inter onnections with one another are shown on Fig. 1.

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Wherein a cutting bit 10 is shown mounted on the tool holder shank 11 which is mounted in the tool holder body 12.

An electronic module 13 containing a memory along with the data transmitting and receiving facilities is shown mounted within the tool holder body 12.

A box 14 representing the power and data transmitting and recaiving facility is shown facing the tool holder. This is normally positioned on a computer numerically controlled (CNC) machine near the tool pickup station from which the machine selects the tools for its subsequent machining operation. The read-write facility 14 is cabled via cable 17 to an alternating current source 15 from which it receives the power for supplying to its module 13 and also to the box labeled 16 via cable 1~ which may be an interface micro-computer supplying data to the module 13 via the read-write facility 14 as well as receiving data from the module 13. The interface micro-processor 210 may be of the type M~6~705 manuf2ctured by Motorola Semiconductor Products and described in the 1984 Edition of the Catalog and Selection Guide.

The micro-computer may be chained via cable l9 to a number of other micro-computers such as those labeled 120, 121 and 122 to a host computer 123.

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34~) Figures 2 and 3 show in schematic form the contents of read-write head 14 and associated circuits and the data module 13. The data module 13 as shown on Figures 3, 4 and 5 includes a memory chip 30 which may be a National Semiconductor type NMC 9346 E which is a 1024 bit serial electrically erasable programmable memory. This memory is capable of retaining its programmed contents through the intervals when the operating power is not present. The power for operation of this circuit is supplied ~rom a coil 31 which is magnetically coupled to a supply coil 21 driven by an alternating current source. The coupled energy received at coil 31 with its resonating capacitor 305 is rectified at a diode bridge 32 and filtsred by capacitor 33. A zener diode 34 serves to maintain the rectifier output voltage at a constant level.

Information i5 received for input data and controlling the memory 30 via thre~ photo transistors 35, 36, and 37 for the data input, clock frequency input and for the memory selsct respectively.

A light emitting diode 39 is used to transmit data read out of the memory 30, which data is amplified by a field effect transistor 38. Resistors 301, 302, 303 and 304 control rn/

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the current to the photo transistor and light emitting diode.
Circuit details of the read write head 14 are shown on Fig. 2 and a component layout of the face is shown on Fig. 6. The light emitting diodes 25, 26 and 27 are used for transmitting signals to the corresponding photo tr~nsistors 35, 36 and 37 of Fig. 3. These diod~s are connected from a +5V at a first terminal of each and then through a current limiting resistor such as resistors 201, 202 and 203 and drive amplifiers 204, 205, and 206 to the respective terminals for connection to the control interface computer 210 corresponding to that labelPd 16 of Fig. 1.

A photo transistor 29 biased via a resistor 28 to a +5V is included for receiving any data transmitted by the light emitting diode 39 of Fig. 3. Its collector output is shown connected to the interface computer 210. The emitter of transistor 29 is connected to ground potential.

A ferrite core Coil 21 shown with the center tap of the pximaxy winding connected to a positive 12 V source is the means by which power is transmitted to the electronic module of the tool holder. The coil 21 is shown with the outer terminals connected to the power amplifier consisting of two field effect transistors 225 and 226 connected in pushpull.
The transistors are driven by a coupling transformer. An rn/

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oscillator 219 has its output via a gate 218 which is controlled from the computer 210. The output of gate 218 is amplified at transistor 217 which in turn i~ connected to the primary winding of coupling transformer 224. A resonating capacitor 23 is connected across the outside coil terminals.
Another item mounted within the read-write head is a PIN light sensitive diode 20. Its cathode is connected via a resistor 24 to a positive 12V., and its anode via an amplifier 22 to a terminal for connection to the interface computer 210.

This diode provides the ability to detect when a data module is in position to be read. This is done by modulating all three LED's on the R/W head on and off at a very fast rate (about 2 KHz). The PIN diode detector 20 receives this light if ther~ i5 something close to the R/W head which reflects back the 2KH~ modulated infrared liyht. When something reflective is sensed, the microprocessor turns on the oscillator 219 and sends the proper signals to the data module to attempt to read it. If it receives valid data back from the module, it signals the machine controller that it has data for it, and waits for further instructions. Although the illustrative embodiment of the invention has bePn described in considerable detail for the purpose of fully disclosing a practical operative structurP incorporating the invention, it is to be understood that the particular apparatus shown and rn~

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described is intended to be illustrative only and that the various novel features of the invention may be incorporated in other structural ~orms without departing from the spirit and scope of the invention as defined in the subjoined claims.

In Figure 7, there is shown an example of a CNC
machine tool system 100 that incorporates a tool storage mechanism in the form of a rotating drum or magazine 102 containing a plurality of tools 104. In this embodiment the tools 104 each include an adapter portion 106 having a tool bit 108 conventionally mounted thereto (see Figure 8).
Adapter 106 lncludes a drive key slot 110 where the transponder 112 is mounted~ The transponder 112 has alternately been referred to herein as an implant or module.
Referring back to Figure 7, a transceiver 114 in the form of a read/write head is fixedly mounted on machine 100.

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I 2 9 ~ ~3 `1l ~ 3 .
Tran~o~iver 114 i6 locelted 80 that it ~ ln op~r, bl~ position to read and write iniEormation into th~ ~ne~nory of the transponder 112 contained in one c~f the tools 104. ~hi8 i~;
conveniently done ~y looat~rlg transc~rer 114 ~d~cenk to the Btat~On in ~nagazine 102 ~'rom which a tool to be u~ed ~ loaded lnto the ~sachine sp~ndle 1~6. There are ~I variety of d~ fferent tool changlng ~ech~ni,sms ~cnowTI ln Ithe ~rt ~nd therefore, the pD~ition of' t~e re~d/writ~e head or transceiver 114 srlll v~ry depending upon the p~rticular cQnstruction of t:he 2nachine tool" Preferably, how~ver, tran~eiver 114 ~s l~cated in ~ po~l~iorl 80 ~:hat ~t c~n read in~or~a1:10n fro~n the tool transponder ~mory ~before ~e t~ol i~ loaded into the ~a~hine spindle and ~n ~ posit~ on 230 that it can write infor~ation, if desired, into lthe t~ol transponder memory a~ter the tool h~s been rer~oved ~ro~ the ~zlchine spindle.
As noted ~bove, aom~ of ~e advantages of t:his approach inolude the po6iti.ve ldentigi~:ation v~ She tool ~y th~ ~achine con~roll er ~e~ore the tool ~ ~c~ual~y u6ed to perform a 2ll~chining oper~t$c~n 3n t~ ~or~l:plece 117 , i . e.; to re3ll0ve D!etal there~rom. Tool parameters ~;uch a~ Dlaximum feed ~nd ~peed ca~ be 2;tor~d in the ~emory o~ the tx~l~sponder 112 which csn 3be re d by t:he tr~nsce~ver 114 pr$or to U6~. Thus, ~e ~ob o~ khe ~achine programmer~ can ~e sn~de ~a~ier since thi~ ~nf ormation need not be p~rt of the pre~gr~m used to control the CNC ~nachine operat~on. In other words, it i~
carr~ ed by the tool inste~d o~ in 1:he c:~mput~r prc~ram.

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Anc~ther aZvant~ge i~ that tool po~nt o~:Ese'cG can be ~tored with~ n the tool and u6ed to correct the ~nachine ~o t:ha . ~t c:an produoe 3ilore accurate p~rts. In a~ition, l~e ~axlmum expect~d life o~ ol c;~n be ~niti~lly ~tored ln the tr~nsponder ~nemory hnd dec:r~ased ~ach time t}le tool ~ used by the ~nach1ne to thereby pa:ovide a r~ ng count of ~he re~aining li~e of t~e tool. V~riou6 other ~dv~ntages will beco2ne app~rent to tho~e ~kllled ~n the art upon ~ ~tudy of ~e drawing~ ~nd ~peci:~ic:~tion ~ontalne~l h~re~n.
~ h~ for~going descrlptlon ~ 18 ~gual ~ppllc:~bility So ~both ~odi~ent6 d~scribed in th~ ~ppl~Lc~tion. The ~ormer e2Dbodiment ~lescribed. ~rl ~onnection witl~ Fls~ur~ 6 ~an ~e even further i~pro~ed ~s will ~e di~cus~ed in connectiorl with Figur~s 3-13.
'rurning then to t~ese drawing ~Lgure~ and beginning w~th Figure~ 9-11 y the sltenlate $~Dbodlment ~mploys a t~an~ceiv~rtran~ponder con~truct~on th~t ~ployE~ A unique comb~ n~tiorl of el~ctro2llagnetic and ~ tro~tatic c:oupllng~ ior use in ~r~ns~nit~ing in~o~at~or ~ack an~ ~or~h ~e~ween lthe tran~c~iver ~nd tr~n6ponder. A6 shown ~ia~ra~matic~lly ~ n Figure 11, the tran~ceiver ~e6 ~ ~odulator 11~ to ~odulate ~
re~arence ~requency provided by o~ illator 117 in accordance w~th ~ nput E~ignals l~beled 0d~t~ lnn w~ich c~n ~be ~;upplied from the m~chine ~ontroller l)r ~icroprsce2~0r æu~ as ~icroproc~ or 16 in the ~igure 1 e3~0di~nent. ~ Dodul~ted l i8 amplifi~d by way oi~ ampligi~r 1~4 elrld ~uppllQ~ to an ~ ~9()~4t) inductor 126. Inductor 126 thus transmits an encoded electromagnetic signal that contains: 1) sufficient energy to power the circui~ry in the transponder 112 and 2~ su~ficient data or control signals re~uired to operate the electronic components contained within the transponder 112. For simplicity's sake, these signals will be referred to as simply "data in" signals and they include such things as clock signals, chip select signals and other operational or op codes known by those skilled in the art as being required to operate electrical components such as the electrically erasable programmable memory 128 contained within the transponder 112.
A suitable memory is the serial electrical erasable programmable memory available from National Semiconductor as component No. NMC934~E/COP395. The required data signals to : read, write and erase such a memory is set forth in National Semiconductor's trade literature which is available to the public~
Thus, the power and data in signals are provided by an electromagnetic coupling between the inductor 126 in the transceiver 114 and the inductor 130 in the transponder 112.
The electromagnetic energy induced in inductor 130 is filtered (represented by capacitor 131) and rectified (as represented by diode 133) to provide the required power for the internal ~ transponder electron.ic components which include a demodulator :~ 132. Demodulator 132 operates to demodulate the encoded data in signals and supply them to the memory 128 to perform rn/

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wh~tever operation i8 de~red 6uch as writing or reading information ~rom ~nemory 128 . ~ypic~lly, ~n ld~nti~lcat~ on code will ~be preprogr~mmed ~nto the memory 128 to prov~de ~
unigue idenl:ificat~on code or t2lg ~or each tool 104. To read ~e data out of ~emory 128, tha appr~pr~ate read coD~2nands will ~ gerler~ted :Erom the tr~rlsceiver controller, tr~n~m~ tted electromagnetic~lly vi~ lnductor 126 1thereby c~u~ing the ~nemory 128 to g~ner~t~ d~ta out s~gnal~ corresponding to inrormation ~tore~ in ~ppropr~at~ly addr~ed loc~tiDn~ in ~e ~ ory 12~. .
Pllr~uant to an i~portant f~ture o~ tllis ~n~lrention, the ndata out" lrl~onna1:1on ~rom ~a~ory 128 i~ transmitted ~lel:trostat~c~lly, as c:ompared to el~s:tro2~agnetically, ~ack to tran~;ceiver 114 . In Figure 11 l thi~; cap~c:itive coupling i8 3hown diagr~mmat~cally by one capacltor plate 134 c:onnected to ~u~table tr~n6mitting c:~r::uitry 13~ ~ln the tr~nsponder 112.
C~pacitor plate 134 ~6 2: ap~ ti~ly coupl~d to a ~econd capac~ltor plate 13~ ln the ~cr~sceiver ~14. Plate 138 ls connected to ~uit~ble receiYer ~plif~ca'c~on ~nd d~m~dul~t~on c:lrcuitry 14 0 whose output ~; c:oupled tc~ the ~achine s:ontroller .
Thu~, ~t can be ~een t~t th~ tr~nE;c~lver-to-tr~slsponder tran~mis~;ion link is prov~ded l~y way c~f ~n elec~ro~agnetic coupling w~ile the transponder-to;trlm c~ver transmi~E;ion link 1~; provided ~y ~ay o~ ~ oapacit~e l:oupl~ng.
technique h~ everal ~dv~ntaç~e~ r ~ome oi~ t~e other trans~i~;6i~ techn~que~ lthough ~t Y;hould be umlerstood that suc:h other tr~n6ml~ion techniques do ~e~ll w~thln the ~road 1:eacl~ngs of the pre6ent lnv~ntiorl. ~For ~x~pls~ n ~11 ~magnetic" 6y~tem i~ u~ed lthat e~ploy~ ~ pair o~ inductors each $n the tran~c~iver and tr~nsponder, there can be E!xperienced an unac ::ept~ble a~ount D~ cro~;~ coupling o~ the electro~nagnetic energy. In o~er word6, ~e very ~trong ~ roDI the power couplirlg coii 1 in th~ tran~c:ei~er carl couple lnto th~ o~31er trarl~ceiver co~ l used to receiv~S the data tran~mitted by the tr~n~pond~sr 1:her~y causing h~rmful 1nterf~rence w~îch c:~n degr~de t~e ~y~tem ~ccuracy. ~en the optic~1 transmis~ion 1ink descr1b~d above ln connectiorl with the ~irE;t embodi~ent o~ the pre~ent irlventiorl ha~ certain drawback~ in that it ~ay be ~usceptib1e to dirt and other debri~ whi~h i~ o~ten encountered in 'che adverE;e m~ch~ ne t901 env1ronment w~ich ~ould degrade the optica1 tran~ sion 1~nk.
In a~dition, it ~pp~ar~ necossary that 1t~e tran~cei~2r and tran~pond~r be ~proper1y ori~nt~d irl order to ~Gtab1ish the appropri~te ~o~municat10n 1ink wh~n opt$c~1 coup1ing iE~ used.

In contrast, the combinatlon oslec:tro~agnetls:-capacit~ve coupling techn~ ~;[ue overt:omeE; t~ese problems at very little ~additi~n~l expense, lP ~ny.
~ r~e ~scha~ic~l conE;trus:t$on of th~s tran~;ceiver 114 e~f this ~mbodislent i~; ~llustrated ln Figure 9. Tr2ln~c~siver or re~d/writQ h~ad pr2f~srably takes the for~ o~ a plaE~t~c outer Elhell 142 ha~flng csp~citor ~lat~ ~ 38 loc~ on one esnd 9~ 3~
.

ther~o~ transverse to the ma~or ~acis o~ tho ~hell 142. The capac~tor plate~ u~ed in thi~; ~smbodiment can con~eniently comprise a th~n Dletallic coat~ng on conYentiorlal printed circuit bo~rd D~ateri~l, although other con~;t~ucti0rls can be u~ed. Iocat~d ~nternally of shell 142 18 an inductor generally deE;lgnated by t~e numeral 126 th~t includes winding 148 wound abotlt a ~f~rrite d:ore 150. A shlelded 3-wire . able ~52 has I:wo of it~ wire6 eolm~cted to ~ppo~;ite ~nd~ of winding 14 8, witb the other wire being conn~ct~d to t~ apacitor plate 138r 5qle shield 15~ o~ c:able 152 1E~ physically connected to a ~netallic part of ~ohirle 100 whieh ~rve~ a~ ~
re~erence grour:d ~or th~ s:tric, co~nponents of both the tr~n~;ce ~ v~r and ~r~n~ponder . ~he internal co~porlent~; within 6hell 142 c:an be conveniently potted with a ~;uitable ~aterial such as nonconductiv~ epoxy.
The trsn$ponder 112 construct~on 1~ ~;ht~wn in Fl gure ~0. :~t al~o employs ~ pl~tlc outer she~ ~5~ wh~ch for~s ~
hou~ing ~or all of ~e tr~n~porlder coallponent~ whis:~ includes s:apaci~or plate 134, ~ndu::tor 130 witl~ i~s winding 1~8 and c:ore 160. Windin~ 158 and capacitor plllte 134 z!lre suitably c:onnected to a printed s~rc:uit board 162 c:ont~ning other ~lectron$c: c:omponents ~or the tr~n~ponder. Prafer2lbly, th~se components will take the ~orm o a cu6to~ lntegrated circ:uit chip in order to ~ch~eve the de~ re~ n~aturization.
The electri ::~1 components within tr~n~E~onder 112 ~hould be rQferanc~d to th~ Iga~a r~ersnc~ pc~ntlal ~15 the 90~1q{~ -) cc~mponent6 in tha tr~n ce~ver 114. ~his ~ay b~ accomplished in sever~l di~ferent ways. In th~ ~mbodi~ent ~hown ~n Figure 10 there 1~ provided another plate 164 ~d~c~nt the ~pposite ~ace o~ the tran6ponder ~hell 156 whic:h :IR oouple~ to the ~lectronlc component6 on the board lS2. When the transponder 112 il; mounted in t:he tool ~adapter 106, thes~l the pl t~ 15~
will e~t~er ~n~lce phy#icnl connection with the ~etal ~dapter or will be ~ui~iciently c:~p~c~t~.rely ooupl~d ther~to ~o that the c~pos~ent~ ~n ~ tran~pond~r ~IrQ r~r~nc:ed to the ~achine potential. ~hi~ c u~e th~ tool ~y?ter 106 i~ phy~ic~lly connecte~ to lthe ~chlne ltool 100 when lt ~ in the tool ~agazine 102. ~rhe tr~nsceiver 114 ~o~ponents ~re referenced to the E~me potenti~l by way of the cable s21ield 15~ ~hi~h i~
connected to t31e ~n~chine 100 a~ well, ~ descr~bed abo~re.
The slegre¢ o~ c~pacit~ve c~upling b~tween transc:eiver plate 138 and tr~n~ponder plate 134 is ~ ~anctlor o~ t~e ~Irea of th~ plate6 and the~ di~ e therebe~ween.
Th~se di~Den6ion~ ean be var-~d accord~ng to well ~ tabli6hed c:apac~ti~e pr~nciple~. K~wever, ~ plate ~ize of 1/2 centi~neter ~ re for plates 134 and 138 h~s provided suf~icient capac~tive coupling even whQn the plates are ~paced apart a dist~nce of about a oot. T~i~ sD~ount of ~pacing i~
prc~ba~ly not going to be uE;u~lly requlr~d. ~owever, it can be appr~ciated t~at 'cwo-wzly l:ommun~catiorl c~n ~e æ~bll hed between the tr~nE~celver ~14 and tr~nE~ponder ~12 t2~t does not r~quire precisla orient~tion there~eltween or ~ny phys~cal c:ontact O Thls~ i6 very deGir~ble ~ n t~e en~rironment which the~e device~ find particul~r utllity.
Figure 12 prov~de ~ ~ore det~ d ~un~:ional block d:l agram ~or lthe tranE;ceiver and tr~n~ponder c:ircultry . ~y way o~E a ~peci~ic ~xa~ple, 08cillat9r 117 includes ~ crystal 165 driving ~n o~clllator network 166 at about a 4 ~e~ahertz ~r~quency. O~cilla'cor ~66 æmpll~ ignal ~nd couples it to an input o~ ~ fr~guency ~h~t keyi~g (F~g) generator 1 ~ ng ~!18 ~!1 ~odulator llSo Bri~ly~ ~SX ~enerator 167 opexate~ 86 a d~vider wh$ch di~Yides t~ output of o~c~ tor 166 by one o~ two dl~ferent number~ ~p~ ng uporl whether the ~gn~l level on 1~ ne 168 coupled l:o th~ 3~odulu control ~nput i8 at a log~cal high (a ~ln) or ~ logic~l low (~ "on). In thl~ embodiment, the output of generator 167 w~ll e~ther ~e ~t ~!1 frequency o~ 307 ~ilohartz or 333 kiloh~rtz re~ul~c~ng from the d~vi8~ on of the o~cillator ~requency by the number 12 or ' ' 13 d~pendirlg upon t~e "d ta inH ~gnz~ ~els on l~ne 168.
~he data in 8igl'18l le~el~ z~re s:~o~en t~ pr~v:Lde tbe nnce~C~sy dnta ~ignal6 to operate th~ tran~ponder circu~try, in partic~llar~ D~emory 128. Con~uently, lthe d~t~ in signal~
n~ed to provide cl~ck ~ nal~, ch~p ~elet:t ~ al~ and the ~ppropriate operatiorlal code6 lto r~3~d or wrlte or ~r~e data withlrl the ~emory. Thi~ i6 all acco2llp~ hed by providing the appropr~ate ~ign~l levsl~; on ~ine 16fl at t~ appropr~a~a~ time ~lotO ~rhe ~us ~c~dula~d output o~E ~SX ~cnor~tor ~67 i~
~npli~i~d by a~pli~ier 124 and coupled to a t~ned t~nX l:irc~it .

employ~ng ~r~ble capacitor 169 and inductor coil 148. As ~1 result, t:he lnductor 148 tr~n~mit~ electromaç~etiG energy haYing su~$cient ~energy oontent to ;power ~¢ tran~ponder components ~nd alGo suf f ~ cierlt data encc~ded ther~n in order *o operAte these c:omponent~.
The ~lectxomagnetic energy transmitted Irom tr~nsceiv~r 114 induces electr~c~l r urrent ln coll 158 in the transponder. The energy i~ recovered by a power recovery c:~rcuit 170 ~nd recti~ed to provide ~ t5 ~olt DC signal le~rel tc~ power the tr~n~ponder component: ~rh~ ~at~ ~n the encoded ~lectro~agrietic ~ignal i~ demodulat~d by ~ i~rQquency ~h~ft keying d~modulator network 171. ~he-particular type o~ ~ory 128 u~ed in thi~ e~bodi~ent reguire~ thre~ different operational 61gnal8 in order to ~unct~on properly. These oper~tionAl 8~gn~1~ are labeled in Flgure 12 a~ data, clock ~nd c~ip ~elect ~gn~ls. A ~nown in g~e ~rt, ~he clock and chip oelect ~l~n~ls ~u~t oc ur at ~pproprl~t2 tl~e perl~ds wh~reas ~h~ in~ormation content on ~Q data llne pro~ides op c~de~ ~at ~o~m~n~ cert~n oper~ion~ ~ro~ the ~emory ~uch a~

re~d, write or era~e ~unctions. Since ~here i~ only one ~o~munic~tion link Srom ~he tran~ceiver 114 (i.e. the alectromagnetic coupling via inductor coil~ 148 and 158) it ~ecomes n~cessary t~ decode the dat~ prev~ou~ly enc~ded ~n the ~lectromagnetic tran~mi~slon to provide th* t~r~s ~eparate operation~l ~ign~ or ~he me~ory 128. In Figur~ this deco~ing ~unction i~ r~pr~onted by A ~oun~er 172 that 9~0~3(~

Eaupplie~ pulE;e po~i ~on modulatlon (PPM) dock pul~es (Tl, T2) to a ti~e ~lot decoder 173. The d~coding sche~e u~ed in thi~
particul~r ¢mbod~m~nt will be d~:~crib~ ~ore~ detail ~,n connection with Flgures 13 snd ï4~ Suff~ce i'c 1:o ~ay ~a~ the encoded infor~ation i~ decoded and coupled to the ~emory 123 neces~ry to c:ontrol th~ desired ~Eunct~ons t:hereo~.
~ u~lng th~t an 2~ppropr~te read co~nand i6 r~e:eived by tl~e t:ransponder, t}~e ~æ~aory 128 prov~des ~ ~eries o~ one~ ~nd ~er~ ~ependi~g upon ~tE~ ~ata cc~nterlt on line 174 .
wh~ch $~ coupled to ~e Dlodulu~ ~ontrol ~rlput o~ ~ diYider 175 . ~en ~ t i8 desired to reaa th~ cont~nts ~rom th~
tran~ponder ~e~ory, the freguency; oi~ the sl~e'cro~agrletic ~nersry ~rom the tra~sc~iver i~ ~t a fixed ~re~uency, here, 330 k~lohertz . In oth~r words, no new data i~ 3~eing encoded ~ nto tha transmitted signal ~rom ~e tr~lnsceiver. Thi~ 330 ~cilohertz "c~rrier" ~gn~ divided ~y a giv~n number ~n ounter 175 dependlng upon wh~ther the dat~ on line 1~4 i8 Z~
~ogical 1 or logic:al 0. In thl~ pzlrticular e~bodim nt, dt~rider 175 dividel; ~y th~a numberE; 2 or 3 ther2~y pr~v~ding an output ~requency c:oupled to capacitor plat~ 174 of 111 or 166 . 5 kilohertz .
Thus, ~n electros~atic sigrlal osc~llating at one of two different fregu~ncies ~ generated ~t cap~citor pl~'ce 134.
T211~ el~ctrost~tlc 6~ c~lpaciti~s~ly coupl~ rc~ug~ ~ir which serve6 a~ ~ d~electrlc to t;h~ e~p~ tor ~plat~ 138 ln the tr~nscel~er. 8uitable ~aTIdpass . ~lt~r~ 176 a~nd 177 ~n the . .

tran6ceiver are u~ed t:o tune th8 trans~eiver tc~ recelve ~;ignal~ ting at the 111 or 166 . S Prequency ranyes w~ile . iltç!r~ng out ~rtraneous ~reguencies. Alt:houslh not ~bfiolutely necessary, a tuned circuit 178 can be ut~liz~d to re~ect 6ignal6 bearing ~ ~requency (her~, 330 RKz~ cor:resporlding to tllat being ~enerated electroma~etil::ally over the c:oil 148 during ~e time transceiver 114 ~ receiv~ ng data . The net result i6 th~t signals bearing one of the two re~quencie~ ~ill ~e Empl~ied by ~ ~uitable ~mplification network 179 ~hich is ~ed ~nto an FS~ demodulntor ne~work utilizing lia pha~e loc~ed loop c~rcu~t 180. A~ 3cnown ~n t~e art, p~ loc:ke~d loop (P$I.) cir6uit~ can b~ u~ed 'co l~ck in to a p~rticular ~requency tmd provide a dlgital output irl re~pon~e thereto.
Thu~, the output of P~ lZ0 i~ the recreation of the ormation or data b~ing read Ixom tlhe ~emory ~28. The output line 181 c~n be ~uitably coupl~ad t~ the ~:ontroller o~
t~e ~utom~ted ~achine tool 10~ to take ~ppropri~t~ tion ~n re~on~e to ~e data ~P~ving b~or~ rg:a~ ~rrom ~ pllrtic~ r tool ~t i~ ~bout to be l~aded into th~ ~chine.
A det~iled ~chemnt~ c diagra~n of the transponder circuitry iE; illlastrated in Figure 13. The indivldual t:omponents performing tlle ~unction~a of the ~unction~l block di~ ed isl connectis~s~ w~th Figure 12 hE~ve ~een ~n~ompas~ed by a dotted line which bearE; the corre~pt3n~ing r~ference nu~er~l a; the functiorlal blc~cX. Th~ c:o~pos~entE~ erein ~aYe ~es~ labeled wi~ industry ~t~ndard compone~t n~b~ and pin ~%90~34~

numbex~; ~own in t~e ~rt. Tn thi~ p~rticular embodiment, the component~ are available ~ro:m Motorol~, Inc. C4nsequently, it i~ believed that thi~ ~igure i~ ~ssent$ally ~el~-explanatory especially wllen taken ~n con~unction with th~ previous d~scription E;o ~at a p~rson o~ ordin~ kill in the ~rt can readily isnplement t~$~ cir~uit w~ thout undue experimentation.
Con~e~uently, a ccmporlent by compon~nt dllsscription i not n~ce~sary 3ceeping wlth the d¢~irabillty o~ D;a~nt~ining the ~psci~icatiorl ~6 clenr and conci~e a~ po~ le,.
Referenc~ to the w~ve~orm ~hown ln F~gur~ lJ. will help in underst~nd~ng the d~tailed operation o~ the ~bodiment of the pre ent ~nvent~on, e~peci~ the decoding funct~on.
As~ume, ~or ~xample, that the mach~ne controller g~nerates data $n ~ignal6 on line 168 (Figure 12) to ~odulate the re~erence oscillating ~gnal 60 th~t the tr~nsceiver 114 tran~m~ t8 an electro~agnetic ~ig~al ~aving ~h~ frequency ~har~cteri~tic~ represent~ in Figure ~4(a3- The electro~agnetic energy iB recti~le~ by a Wheat~tone ~ridge n~twork, ~lltered ~nd r~gulat~ by æ~ner d~ode ~o provide a ~5 ~olt DC re~rence to th~ internal ~lectron~ ~o~ponenta in the tran~ponder. The B~ gn 1 ~rom the tr~nscei~er i~ o coupled through a ~haper device lB2 ~or the purpo~e o~ ~quAring up the rounded lnput wavefoxms. ~he output of ~haper 1~2 ~ coupled into ~n input of a one shot multipl~er 183. The Q output of fl~p ~lop 184 will go hlgh wh~never ~ 3~3 k~loher~z ~gnal is received. ~owever, the logical ~igh l~vel a~ ~he output of 1 X'~3~

~lip ~lop 184 needs to be decoded intc~ three di~ferent control 8~grllal8 ~or the ~nem~ 128; namely~ lock ~ignals~ chip Gel~ct signal~ or data E;ignals 5'o thi~ end, a pul6e po~itian ~odulatlon t~chnigue i.8 used to decode the in~ormatiorl- ~ime ~lot decoder 173 ~n eon~unction with diYider c:ounter 172 provides di~;cret~ ti~e ~lot~ labeled ~1 ~nd ~2 in Figmre 14 (e~
~nd 14 ~ f ), respe~tlvely. To gen~r~at~ i!a chip E;elect ~ignal I
the tr~nsceiver ~ic:roproce~or cau~3 ~ 333 ~iloherSz ~;igs~al tC~ ~t32 ~odulated during the appropriate t~m~ p~rlc~d wlth$n the ti~ lot d~flned by ~1. Thi~ will ~et NAND qate ~B5 which i~
latched ~nlto lstch 186 t~s ~llu~tr~ted ln Fi~ure 14 (~ ;o that the chlp elect ~lgnal can be l~ded into ~e 3l1emory 128 ~t the next ~lock pul~;e. The c:lock pul~es are generated at appropr~2ltely t~med lrlter~ whic:h ~h~ppen repetit~rely regardlesE; o~ whether ~t 1~ llecessary to produc~ a chip ~ielect or log~cal 1 data ~lgnal. ~r~ other word~, tbe tr~n~ceiYer and tran~por~der ~idleN ~uch 'sh~ pul~e tra~n ~hown ~n Figure l~(b) ~ utom~t~Ghlly prc~duc:sad dur~ng operat~on. ~hi~; i8 ~lIDW
the cl~ck pul~e~ are ~nerated ~or ~e ~emory 128. Sf it i6 de~ired to tran~mit ~ logical 1 d~t~ ~ignal, the tran~ceiver controller modul~tes the ~lectro~nagnet$~: ~lgnal ~not 6hown ~r~
Figure 14 ~ o th~t it will produce a 330 kilohert2 signal 21t th~ time 810t T2. In such ~a~e, the NAND g~te 187 will go h~h (Figure 14 (d) ~ which ~; latch~d into l~tch 18~ (as illu~trat~d in Figure 14 (b) ~ fos~ lo;~ding lnto th~ D~emory 128 on the n~axt clocX pull;e. On the other hand, ~ there ~re no ~5 3~ 3 l~gical high output~ ~rom ~lip ~lop 184 during time slot~ Tl or T2 t~en the ~emory 128 interpret~ thi~ ~IS ~ log~ cal zero dJ~t~ ~ignal. Thu~, lt can be ~een that ~11 o th~ s~o~es~a~y ~ontrol ~ignal~ ~or operating the ~emory î28 have b2en provided even th~ugh only one communic~t~on link i6 used.
Assuming thAt ~ re~d coD~mand 1~ generated, the memory 12 8 provide~ a ~erial ~it output 6tr~am to the modulus control lnput of counter 189 ~cin~ up ~e ~i~ider network 175. Dur~ng a s~emory rea~ cycle ~e ~ra~cei~er ~re~uency r~ains ~t a sub~ntially ~:on~stan~ 333 lcilohertz r~te. ~rht~;
~requency i~ divided ~y c:~mter 189 ~y th~ nu~er 2 or 3 dependir~g upon whether the d~ta out ~ vels from the ~e~ory Are 21~ a logical high or logi~:al low level. For ex~mple, i~ the datn bit i~ a log~c~l 1 level the divider 189 will provide ~n output o~ 166 . S kilohertz whereas if the lagical level i a zero tl~en the output requency wouls~ be at 111 kilohertz. Thi~ c~utput ~igna~L i8 conn~cted t~ capacitor pla1:e 134 which, a~ noted ~bc~ve, 1 c:ap~:itively . oupled to transceiv~r pl~te 13~ ~Eor r~celving the electro~t~t~cally ener~ted ~ign~l.
~ hu~, two-way co~uni ::ation i~ establi~;h~d betw~er~
the tranE;ceiver a~nd tr~nsponder ~n a ~anner ~hat malces icient use of the two eom~nuniç~tion lin)ts w~ile at the ~ame ti~e provlding` a highly accur~te ~nd ~sy to u~e dentif ic:~tion ~yste~ . Various :~od~ tlon~ of t~e ~mbod~entE~ disclo~ed in ~e for~goin5~ ~p~ t~on will be~ome apparent t;:~ ~ne E;Xilled in t~e ~rt upon ~ ~tudy of the s~ecific~ltion ~nd followinq t:lalms.

......

Claims

1. In an automatically controlled machine for removing metal from a workpiece by way of at least one tool including an adapter portion and a bit, wherein the improvement comprises:
transponder means implanted in said tool;
transceiver means mounted at a fixed position spaced from said tool, said transceiver means positioned to transmit a signal containing data and power to operate electrical components in said transponder means; and said transponder means transmitting a return signal to the transceiver means whereby characteristics of the tool can be interrogated prior to beginning operations on the workpiece.

2. The improvement of Claim 1. wherein the machine includes storage means for temporarily retaining a plurality of different tools, and wherein the improvement further comprises:
said transceiver means being mounted at a fixed location relative to said storage means.

3. The improvement of Claim 2 wherein said transponder means includes a memory, and wherein said transceiver means is adapted to write information into said memory and to read selected information from said memory in response to preselected commands generated by the transceiver.

4. The improvement of Claim 3 wherein said transponder means includes:
transmitter means for electrostatically transmitting information stored in said memory back to said transceiver means in response to an electromagnetic command signal from the transceiver means whereby a different wireless communication link is used to transmit data back to the transceiver means than is used to transmit data from said transceiver means to the transponder means.

5. An identification system for use in an automated machine tool system comprising:
transceiver means remote from a tool storage magazine having first means for transmitting an electromagnetic signal, and second means for receiving an electrostatic signal; and transponder means located on at least one tool in the tool magazine including a memory, first means for receiving said electromagnetic signal and supplying power to said memory, and second means capacitively coupled to said second means in the transceiver means for transmitting an electrostatic signal associated with information stored in the memory back to the transceiver.

6. The system of Claim 5 wherein said transceiver means is mounted in the machine tool system and wherein said transponder means is mounted in an adapter portion of at least one tool, said at least one tool adapted to be removably inserted into the machine tool system for performing operations on a workpiece whereby information about the tool can be transmitted to a controller for the machine tool system prior to performing operations on the workpiece.

7. The system of Claim 6 wherein:
said transceiver means includes oscillator means for generating a reference alternating current signal, modulator means for shifting the frequency of the reference signal in accordance with certain input control signals, the output of said modulator means being coupled to an inductor for transmitting frequency shifted electromagnetic energy, said transceiver means further including a capacitor plate for receiving the electrostatic signal from the transponder means, the output of said capacitor plate being connected to the machine controller; and said transponder means including an inductor for receiving said electromagnetic energy from the transceiver means, demodulator means for demodulating the electromagnetic signal into a plurality of control signals for operating said memory, with said electromagnetic signal also supplying power to said memory, and said transponder means further including a capacitor plate for transmitting information stored in the memory back to the capacitor plate in the transceiver means.

8. The system of Claim 7 wherein said memory includes clock signals, chip select signals, and data signals to operate; and wherein said modulator means in the transceiver means is adapted to encode said electromagnetic signal with information sufficient to provide said clock, chip select, and data signals for the transponder memory; and wherein said transponder means further includes decoder means for decoding said clock, chip select, and data signals from the electromagnetic energy transmitted from the transceiver means.

9. The system of Claim 8 wherein said modulator means is adapted to shift the frequency of said reference alternating signal at preselected times in order to encode said memory control signals, and wherein said decoder means in the transponder means is adapted to detect the occurrence of frequency shifts in said electromagnetic signal during preselected time slots.

10. The system of Claim 9 wherein said memory provides a serial bit output when information is read therefrom, with the output of said memory being connected to a modulus control input of a divider means, said divider means being operative to divide a given frequency signal into one of two different frequency levels depending upon the logical level of the bits in the memory output, with the output of said divider being connected to the capacitor plate in said transponder means.

11. An identification system comprising a transponder mounted in a tool and a transceiver for reading and writing information wirelessly from said transponder mounted to a machine tool, wherein:
said transceiver including a crystal controlled oscillator having an output providing a reference alternating current signal at a given frequency, divider means having an input connected to the output of said oscillator means, said divider means having a control input; digital controller means coupled to said control input whereby the output of said divider is at one of two frequencies depending upon the digital signals applied to the control input of the divider, a tuned tank circuit including an inductive means connected to the output of the divider for transmitting electromagnetic energy to the transponder, said transceiver further including a capacitive plate for receiving electrostatic signals from said transceiver bandpass filter means for passing signals of desired frequencies received by said capacitor plate, and phase lock looped means for providing a digital output in response to receive signals at preselected frequencies; and said transponder including inductive means for receiving said electromagnetic energy for the transceiver, a memory having a data input port, a clock input port, a chip select input port and a data out port; power recovery means coupled to the inductive means for rectifying the electromagnetic energy received from the transceiver and supplying said power to said memory; demodulator means for demodulating said electromagnetic signal into a plurality of digital signals, decoder means having an input coupled to the output of said demodulator means and outputs coupled to the data input port, clock input port and chip select port of said memory, said decoder means being operative to decode the signals from the demodulator into signals sufficient to operate the memory including reading and writing information therefrom, transmitter means having an input connected for receipt of a given frequency signal received from said transceiver, said transmitter means further including a divider network having a control input connected to the data output port of said memory, and a capacitor plate connected to an output of said divider means.

12. A method comprising:
mounting a transponder in a tool, said transponder including a read/write memory having a unique identification code stored therein;
placing said tool in a temporary storage device;
electromagnetically transmitting sufficient power and data from a transceiver to the transponder to power and read the memory;
electrostatically transmitting the identification code to the transceiver;
comparing the identification code with preselected information; and loading said tool into a machine for performing operations on a workpiece as a result of said comparison.

13. The method of claim 12 which further comprises:
removing the tool from the machine after it has performed operations on the workpiece;
using the transceiver to electromagnetically transmit sufficient power and data to write information into the transponder memory; and returning the tool to the storage device.

14. The method of claim 13 wherein said information written into the memory is a function of the expected remaining useful life of the tool.

15. The method of claim 12 wherein information relating to the maximum feed rate for the tool is also contained within said memory.

16. The method of claim 12 wherein the maximum speed for the tool is also programmed into said memory.

17. The method of claim 12 wherein said electromagnetic signal is modulated by shifting the frequency of a reference signal, and wherein said electrostatic signal is modulated by dividing a given frequency of the received electromagnetic energy by given numbers depending upon the logical level of the information contained within the memory.

18. The improvement of claim 3 wherein:
said transceiver means includes optical transmission means for transmitting said data to the transponder means, photoreceptor means for receiving data from the transponder means and electromagnetic means for transmitting electromagnetic energy to power said transponder means; and said transponder means including photoreceptor means for receiving data transmitted by the optical transmission means of the transceiver means;

optical transmission means for transmitting data to the transceiver photoreceptor means; and inductive means for receiving the electromagnetic energy from the receiver and supplying power to said memory.

19. The improvement of claim 18 wherein the transceiver means optical transmission means and said transponder means photoreceptor means include a plurality of photodiode and phototransistor pairs to establish plural data links for transmitting commands for operating said memory.

20. The improvement of claim 1 wherein said transceiver means includes means for periodically transmitting signals and means for detecting reflection of said signals off of the tool whereby said transceiver means can detect that the tool is in a proper location to perform read/write operations thereon.