DE7417039U - Tool adjustment device for a machine tool - Google Patents

Description

Patent attorneys Dipl.-Ing. W. Scherrmann Dr.-Ing. R. Rüger

7300 Esslingen (Neckar), Fabrkstrasse 24, Postlach 341.

May 14, 1974 _{Tele (on}

ΡΛ 14 rÜkU Stuttgart (0711) 356539

35S619

Telogrammo Palentschulz Esshngenneckat

The Cross Company, 17801 Fourteen Mile Road, Millers, Michigan 48O26 / USA

^T '? T adjustment device for a machine tool

The innovation relates to a tool adjustment device for a machine tool with a surface of a Workpiece machining tool to predetermined target dimensions and with a measuring unit, which after machining emits an output signal indicative of the predetermined dimensions after processing.

The object of the innovation is to create a tool readjustment device to compensate for tool wear, which readjusts the cutting edge or the tool by the entire dimension in a single readjustment step, since it is necessary to bring a subsequently machined part to a predetermined dimension, whereby should be zweckmässiqerweise the cutting edge or the tool in both directions aen adjustable to be able to temperature changes and the like, compensate it..

7417039 04/24/75

To solve this problem, the tool adjustment device according to the invention is provided by the one in the patent claim 1, 21, 27, 31 or 38 claimed features.

The new cutting adjustment device is advantageously used together with a measuring unit which measures a machined workpiece part and emits an analog error signal which is indicative of the size and direction of the deviation of the dimensions of the machined workpiece part from ¹ ^ assigned nominal dimensions.

In a preferred embodiment of the new cutter adjustment device a memory is provided in which the analog error signal coming from the measuring unit is stored and to which an upper and lower limit value comparator are assigned, which determine whether an upper or the lower limit value with respect to the target dimensions is exceeded. If neither an upper nor a lower If the limit value is exceeded, the tool is turned in the opposite direction by an amount corresponding to the size of the deviation Adjusted direction in order to bring a subsequently machined workpiece part to the target dimensions. If either the upper or the lower limit value is exceeded, the number of consecutive Workpieces are counted that exceed the upper or lower limit value; however, it does not become the tool: immediately re-enacted. As soon as it has been determined that a predetermined number of successively machined work piece parts, for example three, exceeding the upper or lower limit value, the tool will by such an amount readjusted that a subsequently machined workpiece is likely to come to the target dimensions. The tool is therefore not after a single determination that a machined workpiece part has reached the upper or lower limit value exceeds adjusted because the tool

7417039 04/21/75

use-reducing dimensional changes due to the normally steadily increasing tool dimensions in the Reoel are small, so that if a large one Dimensional change is detected on a machined workpiece part, it is to be assumed that this change in all probability due to an isolated difference in the hardness of the material is. As well as it is established that a predetermined number of workpieces - in this case three - an upper or

'Exceed the lower limit, it can be assumed that a

rapid tool wear has occurred and that a corresponding tool readjustment is therefore indispensable is.

ν

j The cutting or tool adjustment device that

Used with preference in the new cutting edge adjustment device assigns one from the outside:; oqliche cylindrical Surface, which is arranged on an adjusting element, which in turn for adjusting the tool on the Tool carrier, i.e. the boring bar of a drilling machine and is arranged to be retractable. This cylindrical surface can as a function of the output signal of the tool adjustment device be gripped by a collet chuck, which is rotated by a servo motor is moved. A tachometer coupled to the servo motor generates a feedback signal that shows the actual amount that the tool has been adjusted. The tool adjustment mechanism can adjust the position of the tool to a different extent, so the tool can be adjusted in a single adjustment process can be transferred into the exact position that is necessary to a subsequently machined workpiece part expected to bring on Solla * -> measurements. the Connection of a collet chuck and a tool next element equipped with a grippable cylindrical surface simplify tool set-up and alignment of the servo-motor driven part of the

Adjustment mechanism with that associated with the adjustment mechanism Part of the tool holder because the cylindrical surface has any rotation angle assignment to the

with this yekuppüit. become canoe.

Further advantageous features and properties of the new • tool adjustment device result from the following

Ending description of an embodiment of the counterpart stances of the invention as well as from the subsequent sub-

claimant.

In the drawing show:

1 shows a tool cutting adjustment device according to the inventor "in a schematic block diagram

; position together with a measuring unit and a

Drilling machine, - in a transfer machine, together

; ir, act with a number in the transfer machine

: existing workpieces,

: FIG. 2 shows a tool adjustment device according to the invention in a preferred embodiment in FIG. ^ _n a schematic block diagram,

[ Fig. 3 the one used for automatic tool adjustment

logic circuit of the device according to FIG. 2, in a schematic block diagram,

) Fig. 4 shows a tool adjustment mechanism for the tools

Adjustment device according to FIGS. 1 - 3, in a preferred embodiment, in a schematic representation, partly in axial section and in one

Side view,

j FIG. 5 shows the mechanism according to FIG. 4, sectioned along the

; Line 5-5 of Fig. 4, in a plan view and

! 7417039 04/24/75

Ci J

Fig,

the mechanism of FIG. 4, sectioned along the line 6-6 of FIG. 4 in a schematic Partial representation and in plan view.

7417039 24.0A.75

S ₁ - 6 -

In Fig. 1 a device for compensating for tool wear in a drilling machine 12 is shown. The Kcmpensationseinrichtung has a control unit 14, which with a blade adjustment mechanism 16 nd a measuring unit 18 is in operative connection. the Compensation device 10 for tool wear and the drilling machine 12 are a transfer machine 20 assigned, in which workpieces W are transported through a number of stations, 3 of which are shown in FIG are illustrated. The drill 12 has a drill rod 22 which is an adjustable cutting steel or a tool 24 carries and which can be set in rotation that the tool 2 4 a cylindrical bore 2 6 in the workpiece W generated. After the completion of the drilling, the workpieces are in transferred to an intermediate station, which is referred to as station 2 and in which the respective workpiece during of the next drilling process is at a standstill. Before the next subsequent drilling process, the workpiece W in the station 3 transferred, in which the measuring unit 18 measures the diameter of the bore 26 by the fact that a measuring head 28 is inserted into the bore 26. The measuring unit 18 and the measuring head 28 can after the pneumatic Working measuring principle; they measure the difference between the actual dimensions of the bore 26 and the Soil measurements in such a way that a measurement of air flow or the back pressure resulting from such an air flow from the measuring head 28 into the bore 26 takes place. The measuring unit 18 preferably emits an analog signal on a line 30, the size of which for the setpoint deviation of the bore 26 of the workpiece W is characteristic and that also the direction of the deviation of the dimensions of the bore 2 6 of the workpiece W indicates the setpoint dimensions. So z. B. a measurement output voltage of 3 volts indicate that the bore 26 of the

Piece W has the setpoint dimensions, while an indication of more or less than 3 volts shows a Bohreng 26 means that are larger or smaller than the target dimensions is. Here, the amount by which the output voltage deviates from the nominal value is an indication of the The amount by which the bore dimensions deviate from the target dimensions. The control unit 14 gives on one Line 32 from a control signal, which an adjustment of the tool 24 by the cutter adjustment mechanism 16 does: It also receives a feedback signal on line 34 which is that of the knife adjustment mechanism 16 indicates edge adjustment actually made.

In Fig. 2 there is the control unit 14 and the blade adjustment mechanism 16 shown in greater detail, wherein the knife adjustment mechanism 16 with a dashed line drawn Kastjn is surrounded. The control unit 14 receives on the line 30 the error signal from the measuring unit 18, while you on a line 36 a reference signal from the measuring unit 18 is supplied. When a switch 38 is closed, the analog error signal that is on the line 30 appears, applied to a capacitor 40, so that this via a resistor 22 to a voltage level is charged, the size of which is indicative of the dimensional error of the bore, as measured by the measuring unit 18. The switch 38 is dependent of the respectively discharged. Position of. Measuring head actuated in the bore 26, so that the dimensions of the bore determined at the correct time will. The charge of the capacitor 40 is through a resistor 4? with the input of a high input impedance having amplifier 44 connected so that a signal appears on a line 46, which for the error signal stored in capacitor 40 is indicative.

-B-

One for automatic tool adjustment diersrdc Local circuit 48 receives the error signal appearing on line 46 and that on line 36 occurring reference signals. The logic circuit 48 responds to the difference between the error signal on line 46 and the reference signal on line 36 and issues corresponding control commands Lines 50, 52, which form the control line 32, so that the radial projection of the tool 2 4 accordingly enlarged or reduced. The control commands appearing on lines 50, 52 v / ground e'.nem Gear motor 54 supplied to the z. B. is driven clockwise when the hole is too small, so as to the radial protrusion of the tool 2 4 as a function of a occur on the line 50 *, len signal to increase; it can be driven counterclockwise if the bore is oversized, so that the radial protrusion of the tool 24 depending on a signal appearing on line 52 is decreased. The geared motor 54 is provided with an output shaft 56 provided, which is coupled to a reduction gear 5 8, which in turn again with a pneumatisehen Chuck 60 is rotatably coupled. The amount of Drehbewegungunq of the gear motor output shaft 56 and accordingly of the pneumatic chuck 60 is measured by a rotary potentiometer 62, which via a shaft 64 with the Getricbo motor 54 is coupled. The rotary potentiometer 62 emits an output signal on a line 66, which of the one used for the automatic adjustment of the Werkzov.c logic circuit 48 received and with the on the line 50 or 52 existing command signal is compared, so r * iß the total amount of tool adjustment exactly and can be precisely monitored. A display unit 68 receives the indicative of the actual tool adjustment Signal on line 66; it gives a visible indication

the actual cutting edge position. The Schneidennachstellme ^r 'hanismus 16 is also provided with an overflow protection device 70 which is coupled to the pneumatic chuck βο via a shaft 62 and contains limit switches 74, 76 which can be actuated by a cam 78 which is rotatably mounted on the shaft and indicates when the tool reaches the limits of the setting range. This display is supplied on line 75 to a suitable display device, such as a lamp 76. The output of the overflow protection device 70 f ~ ^ is also a via a line 77 to

For purposes yet to be described, the logic circuit 48 for the automatic tool adjustment is supplied. the Logic circuit 48 also receives a manual adjustment signal via line 78 from one of the manual adjusters j serving logic circuit 80 which is a voltage source

82 contains which a negative Spannüna to a line 84 and a positive voltage on a line 86 and an adjustable voltage on a third line 88, such as this will be explained later. The logic circuit 8O serving for manual positioning receives from a terminal a switch-on signal that is only supplied when the drill rod and the tool are in the correct position for cutting edge adjustment are located. The switch-on signal occurring at terminal 90 is one of the movement in the Clockwise assigned push button 92, a reverse push button 94 and a push button 96 assigned to the counterclockwise movement, these push buttons feed the signal appearing at terminal 90 to an analog AND logic element 98, 100 and 102, respectively. the analog AND gates 98-102 receive the Signals on lines 84, 88, 86; they transmit the signals on line 78, which then connects to the logic circuit 48 for the automatic tool adjustment in still connected in a descriptive manner when the associated Push button is closed and a switch-on signal is sent to the

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7417039 04/24/75

Terminal 90 appears. Accordingly, the negative voltage of the voltage source 82 on the line 78 occurs when a switch-on signal of the terminal 90 appears and the push button 92 associated with the clockwise movement is closed. A positive signal to <^ er T. <=> It-ung B6 appears on line 78 when a switch-on signal is supplied to terminal 90 and the push button 96 assigned to the counterclockwise movement is closed. Finally, a set potential on line 88 appears on line 78 when a switch-on signal occurs at terminal 90 and the reset button 94 is closed. The automatic tool adjustment logic circuit 48 responds to the negative and positive voltages on lines 84, 86, 88 as if they were error signals so that the pneumatic chuck 60 is rotated clockwise or counterclockwise as appropriate. The Rückstelidruckknopf is used ir the tool. To transfer a predetermined position which can be adjusted by appropriate adjustment of the lying on the line 88 and the adjustable potential preferably d ^J e starting position after the insertion of a new tool is.

From the foregoing it can be seen that both an automatic readjustment of the tool 24 by the cutter readjustment mechanism 16 as well as manual readjustment by means of the push buttons 92, 94, 96 are provided. Also be these readjustments because of the interlocks caused by the switch 38 and the switch-on voltage at the terminal 90 only carried out when the tool is in the correct position for aas readjustment.

3 shows a block diagram of the logic circuit 48 for automatic tool adjustment. The signal occurring on line 4 6 and characterizing the deviation of the bore dimensions from the nominal value

-11-

becomes an upper limit comparison unit 104 and a lower limit comparison unit 106 supplied. The upper limit comparison unit 104 also receives an upper one Reference voltage, e.g. B. 3.5 V from an upper voltage generator 108 as well as a lower reference voltage, for example 2.5 V from a lower reference voltage generator 110. The upper limit comparison unit 104 emits an output signal on a line 112 when the on the The signal appearing on line 46 exceeds the upper reference voltage, indicating that an abnormally large Bohrunn has been measured. Conversely, the lower limit comparison unit 105 supplies a signal on a line 114, indicating that an abnormally small bore was measured has been. When a signal appears on line 112 indicating that the upper limit has been exceeded j and if this signal is an AND logic

member 116 simultaneously with one appearing on a line 118 Signal is supplied, ciches indicates that the tool 24 is in the correct position for readjustment stands, i.e. that the boring bar is in the retracted position and the tool adjustment element is on the Pneumatic tool adjustment chuck 60 is aligned, a signal is on a line 120 an upper Limit counter 122 is supplied, which in turn counts to 1 in its counting register. The limit counter 122 becomes three successive signals are supplied indicating that The limit counter indicates the upper limit value has been exceeded in three successive bore measurements on a line 124 a_ Ausoangssigr.ai from. In a similar way, an AND link delivers 128, if there is an output signal on line 114, the correct position if one occurs for the adjustment indicating signal on line 118 Signal to the lower limit counter 130, which is paid into the register of the counter there. As well as the lower limit counter 130 three consecutive of the and-associative

741703S 04/24/75

All 128 signals delivered on line 130 are counted has, the lower limit counter 13O emits an output signal indicative of this circumstance on a line.

Di'i: C; Uf of the line 124 Prcrheinenrlp Aiisqnnasaröhe of the upper limit counter 122 arrives at an AND logic element 136, which also receives on the line 118 a signal indicating the correct position of the readjustment. The AND logic element 136 emits an output on a line 140 when both signals are present on the lines 124, 118; this output signal is fed to an input of an AND logic element 142. The AND Verknüfunasglied 142 also receives on a Leituna 144 a signal that is derived from the menu appearing on the line 77 signal and the inverted in particular with respect to the signal on the Leituna l ^n, so that the occurrence of this signal indicates that "the Cutting edge adjustment has not yet reached one of the limit values - as is also indicated by the open limit switches 72, 74. If the sianals occur simultaneously on lines 140, 144, the AND logic element 142 emits an output signal on a line 146, which is received by a further AND logic element 148. Day AND logic element 148 also receives a signal on a line 150 if no manual readjustment has been carried out via the logic circuit 80 used for manual adjustment; when signals occur on line 146 and line together.

The lower limit counter 130 supplies its output signal to a AND logic element 154 to, which is the correct ^ telluna for Cutting edge adjustment signal is received in the manner already described on the line 118, so that it is on an Ausaanasleituna 158 emits an output signal when an output signal of the lower Crenzznhiers 13Ο and on the Line 118 in the position for cutting edge adjustment specified signal occur at the same time. The one on the exit

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7417039 01/24/75

The signal appearing at line 158 becomes an AND logic element 160, which is also on the line 144 receives a not reset signal and on a Line 162 emits an output signal when both a signal on line 144 and a signal on the Line 158 are present. The one occurring on line 162 The signal is fed to an AND logic element 164, which also has a signal on line 150 receives, which indicates that by the hand readjustment serving logic circuit 80 no manual readjustment has been made; the AND gate 164 performs on line 166 provides an output signal when there are simultaneous occurrences of signals on the line and line 150 takes place.

From the foregoing, it can be seen that signals occurring on lines 152, 166 indicate:

1. That three consecutive bores have been measured which are either greater than the upper reference limit value or less than the lower reference limit value,

2. that the tool is in the correct position for readjustment,

3. that the tool is within its adjustment range and

4. That the manual adjustment serving logic circuit. 8O operation is not set.

As will be explained below, the are on the signals appearing on the lines 152, 166 control signals, which the cutting edge adjustment by the for the correction the deviation between the measured hole diameter in the last measured hole 26 and the target value is correct Allow amount.

- 14 -

The signals appearing on lines 112, 114, which indicate that the upper or lower limit value has been exceeded, are fed to a NAND logic element 168, which emits a signal on line 170 when neither the upper nor the lower limit value of a signal occurring on line 46 is exceeded, which is characteristic of the deviation of the last measured bore. The signal appearing on line 170 is received by a NAND logic element 172, which also receives a signal on line 118 in the manner already described which characterizes the correct position for cutting edge adjustment and which then emits a signal on line 174 when the signals appearing on lines 170, 118 occur simultaneously. The output signal appearing on line 174 is received by an AND logic element 176, which also receives a signal on line 144 which indicates that the limits of the adjustment range of the tool have not yet been exceeded; the AND logic element 176 emits an output signal on the line 178 when signals occur simultaneously on the lines 174, 144. The signal appearing on line 178 is fed to an AND logic element 180, which also receives a signal on line 150 which indicates that the tool is not being readjusted by hand by the logic circuit 80 used for manual readjustment; the AND logic element 180 emits an output signal on a line 182 when signals occur simultaneously on the lines 178, 150. In the following it will be described that. a signal appearing on the line 182 is a control signal which allows the tool 24 to be readjusted after each measurement of a bore 26 if the bore measurement is within the upper and lower limit values, as determined by the reference voltages from the voltage sources 108 and 110, respectively is given in each case.

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7417039 04/24/75

It is now assumed that the workpiece measured last had a bore that was within the corresponding Limit values were as given by the upper or lower reference voltage. The control signal on the line 182 is then assigned to the drive clockwise and logic element 184 and the drive im Linking element 186 assigned counterclockwise. The signal which appears on line 46 and is indicative of the bore deviation of the workpiece is fed to a servo amplifier 188 via a line 190 ^ leads. The servo amplifier 188 also receives a

Line 192 a signal from a deviation detector 194 which is initially at a 3 V level, i.e. at the signal level, which reflects the desired tool dimensions. The servo amplifier 188 compares the on the Lines 190, 19? incoming signals and gives on a Line 195 emits an output signal when the signal appearing on line 190 indicates that the last one measured Bore undersized; on the other hand, it emits an output signal on line 196 when that The signal appearing on line 190 indicates that the most recently measured borehole was oversized. Under the assumption, the fact that the most recently measured borehole 26 is undersized results in the coincidence of one on line 195 and a signal occurring on the line 182 at the AND-logic element 184 an output signal nuf the Lei

device 198, which is fed to a driver 200 assigned to the clockwise movement, which in turn is based on the

j line 50 emits an output signal in such a way that the

drive motor 54 is set in rotation in a clockwise direction and increases the radial cutting edge projection on the boring bar, so that the bore dimensions of the next workpiece part to be machined are likely to be such Amount to be increased that the workpiece part on the

desired dimensions. The tool comes with other

ren words in a single step depending on the

- Adjusted errors. The workpiece part should be oversized

pointed out, the servo amplifier 188 would have on the

Line 196 emit an output signal, v / ai5 means that the AND logic element 186 at the same time on the Lines 182, 196 received signals and emitted an output signal on a line 2O2 which was transmitted by one of the counterclockwise movement associated driver 204 would have been received, which in turn on the line 52 would have fed a signal to the gear motor 54, under the influence of which the gear motor in the It would have been driven counterclockwise in order to remove the radial protrusion of the tool cutting edge !! the boring bar 22 to zoom out so that the next to be edited Workpiece part have smaller bore dimensions would.

When the tool 2 4 is driven either clockwise or counterclockwise, the gear motor 54 is readjusted, the rotary potentiometer 62 emits a feedback signal via line 66, received by the deviation detector 194. The abv. »?: 'chung detector. ^ 4 represents the change in the size the potentiometer voltage and outputs a signal on line 192 indicative of this change. As the tool setting changes, the signal on line 192 approaches the control signal on Line 19O on. As soon as the servo amplifier 188 determines that the signals appearing on lines 190, 192 are identical, the output is either on line 195 or line 196, d = * s for the change was responsible, ended. The deviation detector responds to the reference voltage supplied on line 36 in such a way that after a predetermined period of time after which an output signal on the line 66 is generated Movement of the rotary potentiometer 62 increases the output voltage of the deviation detector 194 on the line is reset to 3 V, with which the initial conditions for the next tool adjustment are restored,

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7417039 04/24/75

If a bore 66 is measured that lies outside the upper or lower limit value, the signal on the guide "- '" g 182 is not output in the manner explained above As already explained, a signal is output on line 152 or line 156, which is fed to the corresponding AND logic element 206 or 208. If the output signal of servo amplifier 188 assigned to the clockwise movement is present on line 195 the AND-logic element 206 received at the same time as the signal occurring on the line 152, the AND-logic element 206 outputs a signal on the line 210 to the driver 2öö assigned to the clockwise movement, which in turn initiates a crancTssicrnsl on the line 50, uel ^ ' ¹ ' = · «« H * »r hprpi ι-.ς described, a tool readjustment is effected in a clockwise direction movement in the counterclockwise direction of the servo amplifier 188 on the line 196. and a signal present on the line 166 is received at the same time at the AND-logic element 208, this outputs an output signal on the line 212 to the driver assigned to the movement in the counterclockwise direction , which in turn generates an output signal on the line 52, so that a tool readjustment takes place in the counterclockwise direction in the manner explained.

The upper and lower limits of the bore 26 of the workpiece W as determined by the upper and lower limit relation generators, respectively 108 or 110 is specified, sir.d is chosen so that it is sufficiently within the upper and lower for the workpiece W allowable tolerance limit. If required, upper tolerance comparators and lower tolerance comparators can be used with assigned upper and lower tolerance reference generators similar to the units 104, 106, 108, 110, which transmit the output signal on the line

- 18 -

7417039 04/24/75

device 46 received and. determine when the bore 26 of a workpiece W is outside the tolerance limits. The control unit k ^ nri here bsi -for Festste! ι "nn" in a workpiece lying outside the tolerance limits, shut down the drilling machine 12.

The preferred embodiment of the knife adjustment mechanism 16 can be seen in particular from FIGS. 4 to 6, in which the blade adjustment mechanism in larger Details is shown. The blade adjustment mechanism Ki has a central, rotatably mounted shaft 214 with shaft parts 216, 218, 220, 222 of different diameters; the shaft 214 can also consist of several interconnected be joined together coaxial pieces. The last-mentioned shaft part 222 is preferably one of these composite ones Pieces; it carries collet fingers 224 which protrude slightly outward, with axial slots being provided which allow the collet fingers 224 to be compressed in a radially inward direction. Coaxial to the shaft part 22 2 is arranged a clamping sleeve 226 which is axially displaceable relative thereto and which allows to compress the collet fingers 22 4 by their downward movement with respect to the shaft part 222. The clamping sleeve 226 has a radially outwardly projecting flange 228 which is provided with a radially outer, cylindrical wall 230 and a radially inner, cylindrical wall 232 each via a sealing ring 234 or 236 cooperates sealed. The flange 228 divides a chamber delimited by the walls 230, 232 into two: he opposing chamber parts, which can be acted upon at predetermined times via channels 238, 240 with high pressure compressed air are. When channel 240 is depressurized and the pressure in channel 238 increases, flange 228 and the clamping sleeve 226 attached to it is pressed down with force, so that the collet fingers of the Weilenteiies 222 be biased radially inward. Will on the other hand

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7417039 04/24/75

the channel 238 relieves pressure while the pressure is in the Channel 240 enlarged, the clamping sleeve 226 is moved with force with respect to the shaft part 222 upwards, so that the spar.r. pliers fingers 2? 4 arrows radially can move outside.

The entire arrangement consisting of the shaft 214 and the clamping sleeve 226 is rotatably mounted in bearings 2 42, 2 44. As can be seen in particular from FIG. 5, the shaft 214 is driven via the reduction gear 58, which a worm wheel 246 seated on the shaft 214 and with a worm mounted on a transverse shaft 250 2 48 is engaged. The cross shaft 250 is driven by the gear motor 5 4 via a suitable intermediate coupling driven. The rotary feedback potentiometer 62 is also driven from the shaft 250 via a suitable Clutch driven so that there is actual rotary motion of shaft 214 indicates.

'As can be seen in particular from FIGS. 4 and 6, the carries Shaft part 216 has a co-rotating cam 78 which interacts with the limit switches 72, 74 mentioned above. The limit switches 72, 74 have actuating plungers 252, 254, which are depressed when the cam 7 8 on a of the pressure plates 256, 258 comes into play. The limit switches are arranged in such a way that a rotation of the Cam 78 causes the respective engaged limit switch 72 or 74 to open by approximately 32.4 ° from the central position. The limit switches 72, 74 result with the interacting with them Cam 78 has an error-free function, through which it is ensured that the limit values of the cutting edge position is not exceeded and no workpieces are spoiled as a result. It goes without saying that this is also because of this can be enough that the pressure of the rotary potentiometer 62 on the display unit 6 8 is monitored.

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j 7417039 04/24/75

The collet fingers 24 of the shaft member 222 are ausqebildet such that they can eryieifen 258 ■ 2ines Schneidennachstt-llmechanismus 260 of the boring bar 22 and r \ x ** tool 24 has a cylindrical surface. The work 24 is designed in such a way that it is moved forward or backward radially by a clockwise or counterclockwise rotation of the cylindrical surface 258 via a movement thread between a tool holder 262 and a threaded element mounted on the drill rod 22. In order to ensure the gripping of the cylindrical surface 258 by the collet fingers of the shaft part at the right time, a compressed air regulator (not shown) is provided, which is assigned to the channels 238, 240 and synchronized with the control commands of the geared motor 54 supplied on the lines 50. So z. B. the gripping of the cylindrical surface 258 at the right time can be produced in that when generating a signal indicating the correct position for cutting edge adjustment, on the line 118 Car channel 238 is pressurized with compressed air, while at the end of the occurring on the line 118 correct position _{for the} signal indicating rapid readjustment, compressed air is applied to channel 2 40.

From the above description it emerges that according to the invention a tool wear compensating control device was created, in which the total adjustment for the respective tool wear does not happen in stages, but in one step, whereby Tool updates made in both directions can be grounded so that temperature changes can also be taken into account. As a special feature of the invention counting circuits are provided that respond to unusual Deviations of the qemesser. Address dimensions, so that changes in the hardness of the material can also be taken into account.

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The subject of the innovation is not limited by the embodiment described above; Rather, the idea according to the invention is capable of a number of modifications and configurations.

- 22 -

ο, η /

Claims (6)

The Cross Company PA 14 Gm claims for protection 1. Tool adjustment device for a machine tool with a tool that processes a surface of a workpiece to predetermined target dimensions, as well as with a measuring unit by means of which a target value deviation of the surface can be displayed after processing is, -thereby g ε k e η η ze i c h η e t, - that the machine tool is a drill (12) with a tool adjustment device (16), a drill rod (22) and a drill steel (2 4) sitting on the drill rod (22) and that it is one on the drill rod (22) arranged adjusting element (222), through which the drill steel (24) with respect to the drill rod (22) is radially adjustable as a function of the setpoint deviation. 2. Werkzeugnachsteiieinriehtung according to claim 1, characterized in that the adjusting element (222) arranged on the boring bar (22), producing a correspondingly different large drill steel adjustment is adjustable by different amounts. 3. Werkzeuqnachstelleinrichtung according to claim 1 or 2, characterized in that it has an adjusting device (60) which is axially at they aligned adjusting element (258) can be brought into engagement therewith and that the adjusting device (60) and the adjusting element (258) can be coupled at any mutual angle of rotation distance. 7417039 01/24/75 4. tool adjustment device according to claim 3, characterized in that the NextLearning (222) a cylindrical surface (258) which is in engagement with the actuator (60) during Bohrstahlnachsteiiung. 5. Tool adjusting device according to claim 4, characterized in that the Stable facility (60) has gripping means (224), through which the cylindrical surface (258) can be gripped during drill steel reaming. 6. Tool adjusting device according to claim 5, characterized in that the The adjusting device (60) is a collet chuck. 7417039 04/24/75