BE623236A - - Google Patents

Description

       

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  Controls for machine tools and the like
The present invention applies in general to systems intended to control machine tools and more particularly applies to systems intended to cause machine tools to automatically execute repeated cycles of machining operations which are composed of 'a number of successful machining phases.



   The most general object of the invention is to enhance the flexibility, precision and timeliness with which machining operations can be accomplished.

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 by machine tools whose position is controlled particularly, although not exclusively, digitally and which are required to perform repeated machining operations for the production of parts.



   An important object of the invention is to make possible the settings, corrections or modifications for a machine tool of the data of a position defined by a program and recorded. More particularly one of the objects of the invention is to provide the possibility of carrying out small adjustments or corrections in a machine tool whose data for the final position have been programmed, so as to take account of small errors. such as measurement errors, tool deflection under load and other variable conditions, which are specific to each machine tool and which cannot be taken into account when drawing up the program.



   Another object is to provide the possibility of making adjustments or modifications within wide limits in a machine tool for which the end position data has been programmed, so as to provide a simple means of making the reference data coincide. programmed for a particular machining with the references particular to a given machining part, to take into account the positioning of the machining part, numerous installations of these machining parts, the positioning of tool, tool length or protrusion, and other variable conditions that are difficult for the programmer to take into account when scheduling the production of various items.



   A less immediate object of the invention is to provide a device according to which these corrections, when they have been made once for different phases of the machining, will be repeated when the complete cycle of

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 Machine operation is repeated a number of times, thus avoiding the need to establish a new program and making it possible to use the same data or information programmed on different particular machine tools.



   Another less immediate object of the invention is to allow the modifications or correction settings to be "incorporated" into a previously established program, at any time whether during the first application of that program or during the course of the program. successive applications.



   Another object of the invention is to enable such modifications or adjustment of the final position data to be made in any direction along any number of axes and accomplished with the aid of an apparatus. relatively simple.



   An additional object is to make it possible, for any machining program, to proceed automatically from rung to rung, to be stopped after each rung, to restart the immediately preceding rung or to be definitively stopped so that the machine can be operated by hand. This flexibility allows the operator to measure the dimension of a machining part resulting from the final position of an element carrying a tool, to separate this tool from the workpiece, to make the necessary res adjustment corrections and repeat the execution of this step to check the accuracy of the positioning, taking into account the adjustment correction.



   Other objects and advantages will become apparent from the following description, given with reference to the accompanying drawings, in which:
Figure 1 is a front elevation of a machine tool, given by way of example in which the present

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 invention is used.



   Figure 1A is a diagram showing the adjustment axes for the tool on a revolver lathe
Figure 2 schematically shows a multi-speed transmission device for driving the rotary table of the machine tool.



   Figure 3 is a schematic illustration of a multi-speed transmission for advancing the tool carriage of the machine tool with different feed rates.



   Fig. 4 is a diagram showing a control system which contains the various features of the invention.



   Figure 5 is a simplified schematic representation of the elements of the system in one embodiment of the invention, which cooperate to provide individual means in the machine tool for "incorporating" small adjustments to correct the positional data for the point. terminal programmed or for the stop position for each of the critical phases in the total machining program and in which a different adjustment means is chosen for each of these critical phases so that the same adjustment will then be automatically included in the phase corresponding in each of the machining cycles which are repeated.



   Figure 6 is a simplified schematic representation of the elements of the system in another embodiment of the invention which cooperate to provide a means in the machine tool to allow "to incorporate" both small settings of correction of the data programmed for each of the machining phases and of the settings within wide limits which are applicable to a series of phases, this figure specially illustrating

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 the differential decomposer method for adjustments over a large range of the data of the position of the terminal or stop point.



   Figure 7 is a simplified schematic illustration of the elements of the system in another embodiment of the invention which cooperate to provide adjustments over a wide range of data from the position of the end or stop point. , representing particularly the method of numerical additions for adjustments over a large interval.



   Figure 8 is a schematic representation of the three-axis drive.



   FIG. 9 is a wiring diagram of one embodiment for position adjusters and selectors.



   Fig. 10 is a schematic representation of parts of servo drives for moving an element and bringing it to predetermined positions, particularly showing the relationship between decomposers and discriminators.



   Figure 11 is a wiring diagram of one of the discriminators and includes means for combining the signals.



   Fig. 12 is a diagram for showing the algebraic addition of an error signal from a decomposer and a correction signal from a centering device.



   Fig. 13 is a wiring diagram of one embodiment of wide gap centering devices.



   Figure 14 is a schematic illustration of servo-control portions for bringing an element: in

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 positions fixed in advance, particularly illustrating the method of the differential decomposer for adjustments in a large interval.



   Fig. 15 is a circuit diagram showing a differential decomposer.



   Figure 16 is a wiring diagram of networks for converting from decimal to biquinary code and for switching from biquinary code to decimal code.



   FIG. 17 is a vector diagram illustrating the sine and cosine voltages of a degital / analog converter.



   Figure 18 is a schematic illustration of a setting means for recording original settings along the X axis, wide gap settings along the Y axis, and long range settings. the tool along the Z axis, with the X, Y, and Z axes shown as associated with the horizontal spindle or tool holder of a machine tool.



   Although the invention has been shown and will be described in some detail with reference to a particular embodiment, it should be understood that the invention is not limited to this particular one. On the contrary, it must cover all the variants, modifications or equivalents without departing from the spirit and the scope of the invention as defined below.



   In order for the invention and its advantages to be fully understood, the basic data relating to a specific application of the invention will now be briefly described with particular reference to a given machine tool. However, we must understand that

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 the invention can be applied directly to other specific basic installations and with models of machine tools different from the one represented here;
The machine tool shown here by way of example is a vertical lathe 20 (fig.l) which, in general, comprises a rotary table 21 journalled about a vertical axis on a base 22 and adapted to support a workpiece (not shown by such means as a jaw chuck 23.

   Columns 24 rise above the table 21 which are connected at their upper ends to a cross piece 25 and support a vertically adjustable cross slide 26.



  This slide has raceways which support a transversely sliding element or tool holder 30 which moves in a horizontal direction.



  This tool holder in turn supports a slide @ a tool holder 31 which can move vertically and carries a turret which can be positioned angularly and which is adapted to carry a number of cutting tools, these tools being capable of carrying a number of cutting tools. be positioned at will in their downward working position. In the figure, a tool holder 34 carried by the turret 32 can receive a tool (not shown) which can work the workpiece on the turntable 21 to give it different diameters and to perform passes along distributed surfaces. posed radially with respect to the axis of the table.



   The slider 31 can be put in a vertical position, on the tool holder 30 by means of a lead screw 35 while the tool holder 30 itself can be placed horizontally in position by the rotation of a lead screw. 36. This lead screw 36 can be driven in any direction and at any of a number of angular speeds so as to give different feed rates or linear speeds to the tool holder 30. In this, purpose, a multiple speed advance transmission is installed in a housing 38. Appropriate position indicators

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 and manual control instruments are installed in the front face of the housing 38.



   Although the characteristic elements of the present invention can be applied to control the movements and positions of various other movable elements such as the slider 31, only the operation of these characteristic elements will be described here for the sake of brevity. for the advance and the positioning of the tool holder 30 in coordination with the rotation of the table 21.



   Table 21 (fig.l) can be driven at any of a number of rotational speeds.



  To help understand how this result is obtained with electric drives, a multi-speed transmission table provided with a number of electromagnetically actuated clutches has been shown in Figure 2. A drive apparatus or electric motor 40 has an output shaft 41 which is connected to drive it to a shaft 42 with either one of two drive ratios in response to energizing or de-energizing of a clutch coil. speed SC1. The activation of this coil causes an atmature 44 to slide against the action of a spring 45 and causes the coupling of a keyed clutch element 46 on the shaft 41, with a gear 48 journaled on this shaft. .

   When the coil SC1 is de-energized, the spring 45 maintains the clutch element 46 in drive engagement with a second gear 49 journaled on the shaft 41. The gears 48 and 49 are respectively in engagement with the gears 50. and 51 attached to shaft 42, so that the latter will be driven by motor shaft 41 at any of two speeds, depending on whether coil SC1 is energized or de-energized.

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   In a similar way a clutch 52 controlled by a coil SC2 is interposed between the shaft 42 and a third shaft 53, so that this can be in **
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 dragged at any one of four speeds according to the particular combination chosen for the coils SC1, SQ2 which are excised, In turn, this shaft 53 is connected in
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 drive socket to a fourth shaft 54 by a similar embtava6 55 controlled by a coil SC3. Finally, the shaft 54 is connected so that it can be driven to a last shaft 56 by a clutch 58 controlled by a coil SC4, so that, for each speed of the shaft 54, the shaft 56
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 can be driven at one or the other of two speeds depending on whether the coil SC4 is energized or de-energized.

   The arbra 56 carries a pinion 59 which is engaged with a bevel gear 60 integral with the table 21.



   Note that, depending on the particular combination! of the sixteen possible combinations of the four clutch coils which are energized, table 21 can be driven
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 at any one of the sixteen rotational speeds POdêibléJ.



   An advance transmission is shown schematically in Figure 3; it has an input element in the form of a gear 61 which is engaged and driven by a gear 62 (fig. 2) which rotates in re-
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 time relation with table 21. As a result, latass 1:. 'input of the feed forward transmission is always. losse .a.2 which is a function of the speed of the table * Between, the admission gear 61 and a shaft 63 four systems of gears and clutches 64, 65, 66, 67 are installed in 'drive and are respectively controlled by four feed clutch coils SC1, ge2e SC3 and SC4.

   The clutch and gear systems 64-67 have been shown to be identical to those of Figure 2 and need not be described. We will only note
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 c estâ-dirc .. that for a given speed of the input gear 6l / "pbw 'a given speed from the table 21) the last shaft 63

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 can be driven at any one of sixteen possible speeds depending on the combination chosen for energizing the four coils SC1 to SC4.



   To control the start and stop of the tool holder 30, as well as the direction of its movement, the shaft 63 is connected so that it can be driven by two clutches forward and backward 68 and 69 normally out of engagement, to the lead screw 36 which is engaged in a nut 30a fixed to the tool holder. Excitation of a forward clutch coil FWD slides a keyed clutch element 68a on via 36 to engage with a gear 68b mounted on the screw and mesh with a fixed gear 63a on the screw. The shaft 63. This will cause the via-mother 36 in a rotation which causes the tool holder 30 to move forward, that is to say from right to left in FIG. .



  Conversely, the excitation of the RTV clutch coil moves the clutch element 69a keyed on the lead screw 36 to engage with a gear 69b installed on this screw and connected by an idle gear 70 to the gear. 63b rigidly attached to the shaft 63. This will cause the lead screw 36 to rotate in a direction which moves the tool holder 30 in the opposite direction, i.e. from left to right. When neither of the FWD or REV clutch coils is energized, the tool holder 30 is stopped even if the table 21 continues to rotate.



   A normally disengaged brake 71 is associated with lead screw 36 and engages when an associated brake coil BR is energized. The operation of the brake 71 after the disengagement of the two clutches 68 and 69 brings the tool holder 1 to a sudden stop without running on disengagement.



   The system shown schematically in figure 4 comprises a system for receiving the data or reader A, which can provide successive sets of information to direct the operation of the machine tool during successive periods of an operation. complete machining. This reader A can for example be constituted by a reader for

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 a perforated strip which receives a strip having rows of perforations representing symbols or figures for the varying adjustment conditions which can be changed from step to step in the complete machining operation.



   Each "block" of data for controlling each rung of machining contains information as to the speed at which table 21 is to be driven. The information will be transmitted to a table D speed storage device which, in turn, controls the energization of the clutches in the speed transmission for table G (shown in detail in Figure 2). Each of these data blocks further contains indicia or information which designate the direction in which the tool holder 30 is to be moved by means of a device shown hereinafter as the lead screw 36 in such a manner. moving the tool carried by the turret 32 (fig.l) to the desired position for the end point.

   This steering information is transmitted from reader A to the direction storage device C which in turn acts on a stop command P to suitably energize the machine steering clutches H (e.g. FWD and REV of Figure 3) .4 In addition, each of the data blocks contains information transmitted from reader A to the feedrate storage device D to determine the feedrate to which it is carried. -tool 30 (fig. 1) moves to the desired position for the end point.



  The device for storing the feedrate D acts, through a selector comparator M to energize the desired clutches in the advance transmission of the machine I, as shown in detail in FIG. 3. In addition, each block of the input data includes digital information which defines the position of the end point in which the tool holder 30 and the cutting tool which

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 moves with it must be transported to perform a machining step.

   This position data is transmitted from reader A to a terminal position storage device B which transmits this information to digital-type signal converters L to analog signals and to J decomposers which are part of the same. a positioning servo-system which produces error signals applied to the K discriminators.



   Finally, each block of data read by reader A can contain information which chooses a particular adjustment or correction device and this information is transmitted from reader A to a storage device F which connects one of the adjusters. determined Q in control relation with the information path between reader A and discriminators K.



   FIG. 4 shows how, when each block of information relating to each of the successive stages of the machining operation is supplied to the system, the device for storing the speed of the table B, the device for storing direction C, the feedrate store D, the terminal point position store E, and the selected adjuster store F to be all placed in the desired conditions to represent this block of input information.



   The elements E, J, K, L operate to provide an error signal whenever there is a discrepancy between the position of the end point represented by the data recorded in the storage device E and the actual position of the movable element which has just been ordered, that is to say the tool holder 30.

   An error signal which thus appears after a block of information has been read and used to produce the movement of the tool holder in a direction determined by

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 the state in which the dietto clutches are located. of the machine H, and at a relative feed rate aêtQrm1 '. by the state in which is the transmission moved ahead of machine I, while the table of machine 21 is
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 driven at a rotational speed determined by the "t4t 'in which the transmission of the machine table is located. These latter components G, H and 1 stupid c' mirées in accordance with the data stored by the storage devices B, C and D.
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  We already know how to get an element of the maahïnèà tool to slow down before it reaches the ftà1 position.



  , or. iexmiHaiU the end point and preferably for tfâlûri1 * shot when it reaches a point separated from the end point by a distance which is proportional to the absolute forward speed of the tool holder 30. the device for storing the position tetai raina le E and L converters, decomposers. and the associated K discriminators have been shown in schematic form in Figure 10, in which the position storage device is shown short.
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 being made up of a number of com¯nutaeu:

  s stepped which are adjusted according to the
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 the terminal position, in angular positions which numerically and digitally represent the position
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 desired terminal. These step switches commdnd6C digital data converters L1 which in turn produce diextita signals. tion ann1: P.) Jo.s for stator windings 90a 91ae 92a of coarse, medium and fine decomposers 90, 91, 92.



  These three decomposers have: 90b rotor windings,
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 91b, 92b which are electrically connected to discr3.ttaca # coarse, medium and fine 94.95 and 96
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 The rotors which carry the windings 90b elb let 92b are mechanically connected to be enttatb4s. in

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 time relation with the movement of the tool holder 30 (fig.



  3 and 10) through successive sets of reduction gears 98, 99 and 100, the gear ratios preferably being chosen so that the rotor of the coarse decomposer 90 rotates at a speed of revolution of a whole.
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 for 25rem of movement for the carriage 30, the rotor of the middle deci-emposer 91 rotates at a speed of one revolution for 25.4rosn of movement of the carriage and the rotor for the decomputer f rotates at a speed of one revolution for 2, 54mm of carriage displacement.

   In practice a greater number of successively driven deconverters could be employed to provide a greater range of driven events for the cart, but the present representation '
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 of the three decomposers provides an understanding of the basic organization and operation of the positioning device *
In short, we can say that the converter;

       from a digital data item to an analog data L1 function to excite the decomposers 90 to 92, so as to produce
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 therein magnetic fields which will induce alternating current error gales in the corresponding rotor windings 90b to 92d which are, in large part, pto4 portional to the sines of and which are consistent from the point of view of phase polarity with angular displacement
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 rotors from a single angular position defined by the digital information represented di; tGà7.eucct by the staircase coauthors E.

   By way of example if a particular position of an end point of 5.6tta (meeuw 'd from a suitable reference point on the path of the carriage 30) is stored in the switches t8 in staircase r4, the decomposer 90 will be energized, from aoxtd quai its rotor winding 90b will produce a signal of <arr6W until this rotor winding has been physically driven at an angle which will mean that the carriage: 30 has reached a corresponding position 58.42mm.

   De marne le decomposer moyeç. 91 will be excited so that his coiled up *
 EMI14.5
 Retor ment 9id will receive an error signal until this rotor winding 91b has been angularly adjusted,

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      in a position which means that the carriage has moved from the reference position 8.63mm plus an integer multiple of 12.7mm. Eventually the fine decomposer 92 will be energized so that its rotor winding 92b will produce an error signal until it has been brought into an angular position indicating that the carriage 30 has been moved 1.14mm plus a multiple. integer of 1.27mm.



   Unless the carriage 30 is in the position of the terminal point represented by the information stored in the staircase switches E, the rotor winding 90b will produce an AC error voltage which depends in magnitude on the difference between the current position of the carriage 30 and the stored information which represents the position of the end point with an approximation to the nearest tenth of 25.4mm. The phase polarity of this voltage will correspond to the direction of this difference.



  The rotor winding 91b will produce an AC error voltage depending in magnitude and phase polarity respectively on the magnitude and direction of the difference between the actual position of the carriage 30 and the stored information which represents the position. from the end point with an approximation to the nearest hundredth of 25.4mm. Finally, the rotor winding 92b will have induced an error voltage in alternating current which depends in magnitude and in phase polarity respectively on the magnitude and direction of the error between the position of the carriage and the stored information representing the position of the terminal point to the nearest thousandth of 25.4mm.



   Although the error signals induced in the middle and fine rotor windings 91b and 92b may pass

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 through several zeros or zero values, while the carriage is moved a relatively long distance to reach the desired position for the end point, the movement of the carriage is not interrupted because at these times the rotor winding coarse 90b will not produce an error signal corresponding to zero or zero.



   The three discriminators 94, 95 and 96 are very substantially identical.



   When controlling a machine tool such as the vertical revolver lathe 20 (fig.l) to repeatedly perform the complete machining operations consisting of a number of phases specified in digitally [. a program which has been read from a perforated tapeÇ * it is impossible when establishing instructions to be that must / followed for each machining phase to anticipate - and to take into account a number of factors variables that can affect the dimensions in the finished workpiece.

   These factors produce small errors and include lead screw backlash or deflection, variations in measurements, tool wear, tool deflection which varies with distance from the slide.
31 to carriage 30, the different deflections for the tool according to the different cutting depths, etc ...



   Furthermore ; if an information program is given for successive machining phases and is to be used by a number of similar machine tools of different manufacture and age, the wear of lead screws and gears as well as their play will be different for each machine tool. These different factors cannot be taken into account when establishing the program.



   Simply positioning the carriage or other movable machine tool element to a specific point on their travel paths cannot ensure that the cutting edge of a tool will attack the workpiece on the table 21 in such a way that this part

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 EMI17.1
 will be worked precisely z. the dimension wanted * n1 inaccuracies of the order of 'o, lti5nan are suscepcib1ad. to occur and are: due to factors that cannot be taken into account in establishing the program. Of course, certain positions for an end point in which the carriage or one of the machine * tool elements can be brought are not critical and do not affect
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 dimensional accuracy of the machined part.

   If the cha "riot just has to pull the out ... backwards:. Before approaching it to a different level of the room worked the point where this not particularly critical backward movement ends.
To make it possible to work machining places with a high degree of precision from a
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 given program of instructions concerning the speedSdd.4 em,, "the table, the directions of advance, the values of the forward- and the positions of an end point for a series of machining phases, the invention has planned to allow the operator:

     
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 of the machine tool "to register" a correction of P () lJ. ' ... "tion which will modify the position of the end point of the element
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 Movable of the machine tool slightly from the PO.t'1 tion initially set by the input data. The condition is such that an individual correction can be made. made for the position of the endpoint for a number
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 any of the machining phases and the setting which has been at M once for. a given phase will be effective when the same complete machine work is repeated a certain time! number of times.
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  In addition to these possibilities of power iàtÓ4 'reduce a control system of means allowing an adjustment or a modification of small dimension for the data relating to an end point entered in the program, according to a,
 EMI17.8
 Other characteristic of the present invention, the control sytcricô comprises a means making it possible to extend the field *

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 EMI18.1
 application of the setting and making possible tim4iida tions of the data appearing in the program in a trbo grâha interval.

   This wide interval adjustment has, in accordance with the invention, been provided along a number of measurement axes to allow numerous "adjustments" of the tool on that axis, i.e. say that means are
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 provided in the machine tool to take into account the dieedm between the nominal length and the actual length
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 of a tool or between the nominal protrusion and the actual protrusion thereof. The present invention also applies to: the provision of means for allowing adjustment over a wide range along one or more of the
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 axes to allow "a factory setting" for 1'a1: Lgrtdtn.rit between the references of the data entered in the program and the references of the part to be machined.



   To provide a device for modifying *
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 the data for the terminal point to be brought to the progtamma in order to take account of small variations in the dtmenatjnt 'a number of position regulating devices or correction signal generators are used and
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 one of these devices is put into operation for ltuü. machining phases by a choice made in accordance with 1ft training which constitutes part of the instructions patir this machining phase.

   The data or selection code intended to designate the particular adjustment device "'which will be effective during a given machining phase output stored by the selected memory F (fig.4) which.! Its task chooses one of a A number of adjusters Q and tidd CQ1Ul- This effective to send a correction signal to the K drives. The polarity and magnitude of the correction signal is determined by the setting of the adjuster.

   This signal is algebraically added to the signai
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 error supplied to the discriminators thus bringing the 'P # OM duction of a null response signal and stopping the nlt4tlsemct

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 of the mobile element of the machine tool when it reaches an end position which is at a selected distance and in a selected direction from the position of the end point designated by the data contained in the end position storage device E.



   An embodiment of this device for position correction has been shown by way of example. In this figure, a transformer
160 has a primary winding 160a connected to the alternating current supply lines L3, L2 and a secondary winding 160b provided with a grounded central tap, The voltages appearing in the output conductors 160c, 160d of the winding secondary 160b consequently have the same amplitude but phases of opposite polarities.

   To store the information coming from the data reader A (fig. 4) which designates one of a certain number of adjustment devices which must be effective during a given machining phase, a multiple switch 165 (fig. 9) is used, this switch comprising brushes 165a, 165b connected to the same shaft 166, this shaft with its associated brushes can be put in any one of a certain number of angular positions so that the brushes come into contact with one of a number of stationary contacts, in response to data provided by reader A of Figure 4.



   For example, switch 165 may be a stepping relay which is placed in any of its possible positions in response to information read.
On a tape punched by the input data reader.



  Since this is a well known technique, the apparatus for actuating the shaft of this relay 166 has not been shown.



   The adjustment devices for the generators of the correction signals have been shown as comprising

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 a number of potentiometers P1. P2, P3, P4, P5 ....



  Pn. The lower ends of these potentiometers are all connected to line 160d. The upper terminals of these potentiometers are selectively connected one at a time to the output conductors 160c by the brush 165a.



  As the shaft 166 is placed in its successive angular positions, the brush 165a successively joins the line 160c to the upper end of the potentiometers P1, P2, P3, P4, P5 ... Pn. In this way, the setting of switch 165 is made to select, i.e. energize, one of several available potentiometers.



   To indicate which of the potentiometers is effective at a given moment to provide an adjustment to the position of the end point of the carriage 30, each of the potentiometers is connected in parallel to a pilot lamp Pla, P2a, P3a, etc. When any of the potentiometers is selected and energized, the corresponding pilot light will light up to indicate to the operator the potentiometer which will effect a change in the final position to which the carriage 30 is moved.



   Each of the potentiometers has a manually adjustable slider Plb, P2b, P3b ... Pnb. When the slider of a selected potentiometer is in its middle position it will not receive any voltage as long as the opposite ends of the potentiometer are connected to secondary winding 160b. If, however, the cursor is moved in one direction or the other from its central position it will gradually receive an alternating current voltage of greater amplitude of one phase polarity or the other, i.e. say that it will be in phase with the supply voltage which appears in the lines L2, L3 or will be out of phase with respect to these.



   To transfer the correction signal that appears on the faders of the selected potentiometer, all the

  <Desc / Clms Page number 21>

 
 EMI21.1
 ± li> a Prib cursors are connected to 8taCionnaM contacts <respective associated with the broom 165b. Thus, by exeniplaj if the switch brush 165a is in gâ Second position so as to excite the potentiometer P2 by getting rasped to it by the secondary winding 160b, 14 batliti 165b will also be in its second position by joining ;

   eh accordingly the potentiometer slider P2b to brush l5b4 1 $ switch brush 165b (± îg.9) leads directly to must% CI input correction terminals in the middle and fine decdmpogcute, 95 and 96, For perttttetCM to understand * 6W, 2nt these correction signals bring & odificat: iona in the final position of the point tt & rmitta towards which Ip carriage 30 is moved, it is good to refer to 19 figure II. As seen in cQl1ei; the AC voltage correction signal (which at Urte .. '' amplitude and phase polarity determined by the r4stti $ ti '
 EMI21.2
 of the potentiometer cursor in operation appears
 EMI21.3
 between CI and 105 input terminals.

   A part of ôi $ riii ', of correction efltt absorbed in passing by a pobenti <Kflèt * é 170 and tîfânsmtsG through a resistor 171 to control 1 bBtt of the addition amplifier 108. te ,,. '"#.' , signal of election constitutes in itself a signal * M 'wff * reur "d * ai pilt [ad4 relatively weak which is of kind positive bit, sbit nègiatiï, The signal" error "pr1rtoa'.Í'pi ': \ qu6 at bûtfties 105 and 106 has a value that is 96 hat i * ti dl ± ± ± eîfe i6ed between the current position of charity 30 and. the positive desire which is represented by the wealth in your storage device. This signal can also be positive or negative, that is to say with a
 EMI21.4
 phase polarity or the other.

   The addition amplifier
 EMI21.5
 108 operates to algebraically add the signal db "ët4î which appears at terminals 106 and 105 and the signal of ettëttlbh which appears at terminals Cle 105 (as well as the signai dtantleipatiôhi if this then appears between them.

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 Al and 105) Conne result of this algebraic addition
 EMI22.1
 the amplified net control signal which appears at bar 108b is larger or smaller than it would be if only the true error signal had been amplified and that by an amount which is controlled by the setting of the heart - sor for the chosen potentiometer or the generator due to correction.
 EMI22.2
 



  When the discriminator of the figure it has & neither one or the other of the relays PL, Ml to be energized and thus produces the displacement of the carriage 30 varë the po8i <iio derived for the terminal point) the error signal Ytaie which appears at terminals 106 and 105 will decrease ptogeodoile ment in amplitude. N4arum & ins a zero response from peo will only when the command signal net r'èUltabt from the algebraic addition of the true error signal and the correction signal has been reduced to a quantity itt ± é # i & ir'i to a quantity fixed in advance.

   For this purpose both views PL and MI will be simultaneously de-energized for aOl'tn8 '"a zero response when the carriage 30 has been Q6pi'. Fton not at the position designated by the tônsmâgalitvées data for the terminal point but at a position in the beide taorte, is killed on either side of the end point it bzz owing more or less over an infinitesimal distance which raz represented by the adjustment of the potentiometer d0K? oi? rÊcliididi chosen.
 EMI22.3
 The adjustable cursors at the 4-meter side Plb ... Pnb (ìg.9) can be associated with
 EMI22.4
 Scales graduated directly in hundredths of a millimeter to allow the operator to "register" the desired correction for the position.



  During the initial journey for a given ptdgtanta of information, the carriage 30 can be stopped at the end of each of the positioning phases. The dimension
 EMI22.5
 which will be machined on the workpiece, with such c4ilôt in this position, can be measured after 4 + oi ijUle4. the slider 31 lightly by hand to make * a cut.

  <Desc / Clms Page number 23>

   In this case, in the event that there is a dimensional inaccuracy, the operator can bring back the movable carriage 30 so as to separate the tool from the workpiece and then make an appropriate adjustment in the adjustment of the selected potentiometer.

   The positioning phase is then reproduced, a second test cut is made and the part is measured again to make it possible to see the final position resulting from the end point programmed and modified by the action of the potentiometer which comes from be adjusted, produces exactly the desired simension on the workpiece,
This process can be folded over to the end of each of the critical positioning phases during the initial positioning operation. Once an initial pass has been made and the Potentiometers $ chosen for some of the phases have been adjusted to provide the necessary position corrections,

   these potentiometers are kept in their settings. So when the total machining opera- tion is repeated any number of times to produce a certain number of identical parts, each time the control system receives the input data for a given machining phase, the switch * selector 165 (fig, 9) will be placed in the same position so that the same correction potentiometer will be placed in effective connection with the discriminators and the modification or correction will be carried out in the final position of the terminal point.

     The apparatus for accomplishing the correction or adjustment of the positions of the carriage relative to those which have been programmed and which have been designated by the information supplied to reader A, has been described above in some detail. However, it seems that a better understanding of the overall relationships and the cooperative functions of the elements of the system to produce this

  <Desc / Clms Page number 24>

 The advantageous result will be better understood from a short summary with reference to Figure 5. Figure 5 is a schematic and illustrates only those parts of the present system which take part in the correction or adjustment of the position.



   Referring to Figure 5, the input reader A receives successive sets or blocks of information supplied by a suitable recording device such as the perforated tape 200, As noted above. At top, each block or set of information may contain a designation of the speed chosen for the lathe table, the relative feed rate chosen for the carriage 30, and the desired position for the end point.

   It is impossible, as noted above, that the programmer who prepares his information sets in the first place, can predict and take into account tool wear, tool deflection, excess clearance and / other imperfections in machine * tool gears and screwdrivers, Instead, the programmer can include in each information block a selection code that will correspond to one of several adjusters different or generator / correction signal,. When reader A reads each block of information, it will not only transmit the desired position information to the storage device
E, but it will also transmit any selection code to the chosen correction storage device F.



   These selection codes are represented here in three successive blocks on the perforated strip 200, SC (PI), SC (P2) and SC (P3). In response to receiving these respective selection codes, the correction storage device F places the movable brush 165a on a cascade relay 165 at a corresponding contact point connected to the rheostat P1, P2, / or. P3.

  <Desc / Clms Page number 25>

 



   These rheostats are shown here as a form of an adjustable signal source or generator. Note that all these rheostats are connected to a voltage source, so that the voltage appearing on their cursors and: which is transmitted by the cascade switch 165 to an algebraic addition device K depends on the denial position in which these cursors potentiometers have been placed
In operation therefore, when an information bold is received, the position of the programmed end point is transmitted to the position storage device E and the selection code is transmitted to the storage device F. If one admits that the Selective SC code (P1) is read,

   the brush 165a will take the position which is shown in FIG. 5 and the cursor of the potentiometer P1 will then be connected to supply a correction signal to one of the inputs of the algebraic addition device K.



   The position comparator shown in FIG. 5 receives at its first input the signals from the position storage device E which indicate the position of the programmed end point; it receives at its second input information provided by a position reader ', or signals which represent the actual position of @hamiot 30.

   The output of the position comparator is A first or true error signal which is transmitted as to the second input of the algebraic addition device K. The output information of the addition device which appears in a line 220 is therefore a compound control signal which is the algebraic sum of the error signal and of the correction signal collected in the potentiometer P1. This compound control signal or net control signal is supplied to the I, P driver which rotates lead screw 36 to move carriage 30 until it reaches a position at which the compound signal is reduced. to zero.

  <Desc / Clms Page number 26>

 



   At the moment; the true error signal. produced by The position comparator may not be zero. Thus, the final position of the carriage: 30 is not that which was programmed or designated by the information originally supplied to the Armais reader is a position which is located at a distance from this which depends. the adjustment of the brush of potentiometer P1 and thus the magnitude of the correction signal coming from the selected potentiometer.



     1, The machine tool operator can adjust the brush of the potentiometer P1 to change the final position of the brush 30 and thereby compensate for tool wear, tool deflection and other factors including the programmer. could not take into account.



   When the next phase of the ensemble, the overall machining operation is performed by reader A which receives the next block of information, another of the potentiometers. P1 to P5 can be chosen thanks to a different selection code that will be. included in this information bowl. Thus the displacement of the machine tool corrections will depend on the adjustment of the cursor of this particular potentiometer.



   Once the operator has made the machine tool go through a complete cycle to work a given machining part; and adjusting the various potentiometers to produce the precise positioning of the carriage 30 and of the tool carried by the latter during each of the phases, the system can be actuated in a repeated manner To produce a large number of Machining parts Displacement. Corrections established previously for each phase of the program are accomplished automatically because the same selection code will cause Salai 165a to connect to the corresponding potentiometer during repetition of a given phase.



   This represents a development of great importance and an advantageous stand for the order.

  <Desc / Clms Page number 27>

 
 EMI27.1
 automatic machine tool and allows the use of programmed data carried by a perforated tape or other form of recording to be used with a
 EMI27.2
 rity of different machines and under different conditions of tool wear and deflection.



   With the system just described, which includes position adjusters in the form of adjustable rheostats which vary the angular position for which the fine correction 4-rotor decomposer 92b gave a zero signal, there is a limit. determined by the magnitude of the adjustments that may be made due to the limitations of the apparatus. We will understand that
 EMI27.3
 if we examine the physical construction of the decomposer and. its electrical operation.

   With a decomposer of
 EMI27.4
 model described, a "zero" signal is reached at 0 "and 10 ', that is to say in the two positions of the rotor of the decomposer in which it is angularly aligned with the field reader produced by the sine and cosine voltages supplied respectively to the field windings In this rotor position no output voltage is induced in
 EMI27.5
 the rotor. As a result, the maximum by which the "zero" could be shifted in a single decomposer would be 90 "from zero to On or 199". It will be remembered that in Io p, I.en '. system, the end decomposevr turns 3eo "for each of the 2.54mm movements of the lead screw.

   With this 90 "decomposition of the movement a! 9tBaB! Sn & the rotor represent a quarter of a revolution or 0.63mm as the maximum possible offset distance for the" zero "point.
 EMI27.6
 circuit, which Cfnnprenç! a discriminator circuit (fig, 11) to receive the zero signal and, in response to this, to stop actuating the advance clutches, it has been observed that in practice the discriminator circuit will not work satisfactorily when a bias signal is introduced which is about
 EMI27.7
 36 to the displacement of the rotor of the ddeomposer, 36 to displacement;

   

  <Desc / Clms Page number 28>

 for the rotor of the fine decomposer corresponding to approximately 0.23mm of the linear displacement of the charion and thus this displacement of 0.25mm constitutes approximately the maximum adjustment which can be obtained with the current system when position adjusters PI to P5 (fig. .9) are used to introduce and add a bias voltage to the signal from the fine decomposer 92 which is used to operate the discriminator circuit. turn explain the above with reference to figure 12, the sine curve R. represents the output voltage of the rotor of the fine decomposer.

   When there is no bias voltage from the position adjusters, note that this voltage curve R1 is negative and then positive as the rotor turns 360 through two zeros. Thus the signal R1 is supplied to the circuit of the discriminator 96 and represents the error signal which is algebraically added with the correction or adjustment signal supplied to this circuit by the rheostats P1 to P5.



   If a negative bias voltage A1 representing the correction or adjustment voltage from a position adjuster P1 to P5 is introduced and added to the signal R1, the resulting signal is represented by the curve R2. Note that with a negative voltage A1, the zero point has changed from X1 to X2 representing approximately 18 of the movement of the rotor which is equivalent to approximately 0.125mm of the movement of the carriage. Referring now to Figure 11A, it will be seen that if a negative bias voltage from A2 is introduced, the voltage curve R3 is always negative, it barely touches the zero axis and therefore does not pass through zero and does not produce a zero signal.

   It has been found that the discriminator circuit of Figure 11 will not respond to an input signal having this voltage to cause thyratrons 120 and 121 to kick in and disengage the advance clutches, thus stopping the screw.

  <Desc / Clms Page number 29>

 
 EMI29.1
 mother of the cart :.

   In fact it has been observed that the tenalori 'of the maximum elimination which can be introduced is the value A * (fig. 12) which brings about a displacement of the zero point from xi h X3 equivalent to approximately 36 * of the movement of the rotor of the fine decomposer , i.e. 0.25mm from the movement of the carriage
 EMI29.2
 The system of adjustment for low dimenions which is to be described therefore comprises the tiodiiitad- tion of the position or the adjustment of the terminal point by the
 EMI29.3
 displacement of the zero point of the decomposer at the end of 92 and is Ott - logically limited consequence to very weak settings diej:

  ane0t To enable modifications or adjustments beyond these distance limits, the present invention provides a device for producing Signals representing the data corresponding to the modification and combining these signals with signals representing
 EMI29.4
 programmed data, before these pro * free data signals or their analog equivalents are converted by the decomposer system into position or displacement error signals.

   In this way, the limitation which made the maximum possible distance is limited to the corresponding linear distance is completely eliminated.
 EMI29.5
 to 90 "of movement of the fine decomposer and, practice even less than that.



   FIG. 6 schematically shows a control system containing a device for -
 EMI29.6
 get this result. It can be seen in this figure that the syôte comprises a storage device for a selection exerted on an extended range FW and adjusters for this same range in the blocks W to record on the
 EMI29.7
 machine tool a distance or a dimension which will be tt8 picked to modify the position digit of the terminal point read? go = madifiirx i: K Khii & a: in pMUrhnt dur la band enresitt * Hollow. According to this diagram, the signal from the FW storage device is combined with the signal from the

  <Desc / Clms Page number 30>

 J.C. "digital / analog" decomposers and converters



  In this way the field vectors which represent: the terminal point and which are produced by recomposing the sine and cosine voltages coming from the digital / analog converters are displaced by an angle which depends on the magnitude which has been recorded in the adjustment. at large intervals. This operation is carried out by means, represented in FIG. 15 as a circuit representing a differential decomposer RD and this embodiment of the invention will be the one to which reference is made to describe the method of differential decomposition.



  It should be understood that the modified sine and cosine voltages from the RD differential decomposer are supplied to the JR decomposers which produce an error signal continuously representing the distance to the end point, and which is used by the terminal point. action of discriminators K to activate the drive device (advance).



   In the block diagram of figure 7 there is shown a control system which includes a different device for the adjustment or modification of a terminal position in the wide interval adjustment. While the control system of figure 6 combines, by means of a differential decomposer RD, the analog sine and cosine voltages equivalent to the digital information read from the tape (i.e. after the programmed digital data signal has been converted into a sine voltage and cosine), with a signal representing the adjustment or modification of dimension,

     in the present variant this adjustment or modification of dimension signal is combined with the digital data signal programmed before the latter is converted into analog electrical voltages
To obtain this result according to the invention, the output signal of the tape reader (digital) is combined or added with the signal of sottie coming from the devices of wide range W (digital) for the axis.

  <Desc / Clms Page number 31>

 
 EMI31.1
 des 9 pu t'Mt9 4th Vf ç # 1. oombin4 signals.

   (4tg .., are then converted into voltage $ aine and cosine AU410841quo
 EMI31.2
 pae des moren. oent voprdoontês here like ë8a @ qommxi
 EMI31.3
 digital / analogue weavers, This second form of igè4lîggo tion will therefore be designated as the method 4 '* 444 $ & M |
 EMI31.4
 digital,
 EMI31.5
 01 one fa pgppvço in figure 4, or * vo1 '! $ This figure represents schematically the ft4% eq .. realization 4th Invention for the modification * #a 3.3 pej? W tion of the point t; mtn41t PQ, 4v le low dimeoptp setting # l input A data reader * provides; a fttovtaâftt signai from each one das bippo of data on the tape which was the dJLappsjLt:

   'ngittag? to choose 1 '4193 J * 4 f turns of PQion, h4tata for a phase pa # $ 4wSA # ² # of the operation of 14 machines, In this way, pn pi # t.' a p'1Qulier device in which previously rolled-out MS $ 4 dqnndpe m are stored. This oAr4çt6V4 # 11 tick is opn4orvée lang the system present qmî. As a device for not ge $ lggço small dimension evoet b04 a diapppi1t povfîf the settings at large intewall, the previous description was limited to a system.

   ItanFa & fNflNH of gato distance adjustments along a single 44 to pgU 91 will fogilemene that the system can &% V9 pourndv to provide adjustment along 4th one of several ae? & ± in practice we oproeg4ror4 the settings for a ceveon npmbre 4'anço and I block innovations on In band o.3'Iq. d will be an indication of the Axis along which *? $% $ W8 | MW # is made, The present system v4 Being described for 490 includes its with multiple # ne $ so as to show çmme4e 19
 EMI31.6
 system can be built in practice.

   
 EMI31.7
 Referring to Figure 6, the 8Qh6 of blocks represents a control key comprising a
 EMI31.8
 device for small adjustment and having
 EMI31.9
 also Mn dispas, ifci ± providing a 14yge setting

  <Desc / Clms Page number 32>

   interval along one or more axes. This is shown schematically in Figure 6 in which the wide gap adjusters W include rows of switches (or equivalent devices) for recording a wide gap change along a number of axes.



  The input reader also provides a signal which selects a particular row of switches for a particular machining operation or series of operations and designates the measurement axis. In general, this is in accordance with the system described above, but the selection signal is in this case obtained in a different way.

   The present system is particularly useful for providing "tool setting" in machine tool control, i.e. means for recording the difference between the nominal horizontal length or deviation of the tool. , which is used by the programmer in establishing a dimension defining the position of the end point and the effective horizontal length or deviation of the tool which may be different from the nominal dimensions by a significant amount for a particular tool placement , or the programmer may ignore the tool length or horizontal deviation, and the values, totals for tool dimensions on the x-axis or the axis may be Y can / read by the operator.

   Of course, one should not be limited to this use, however, for illustrative reasons, the invention will be described in application to the use of a "tool setting". Figure 1A, this "tool adjustment" includes an adjustment for the tool length and an adjustment for the horizontal tool offset. The tool length in this case is measured from the turret face to the cutting edge, which is a vertical Y dimension while the tool gap is measured horizontally (X) from a point located in line with the center of the tool loss. Consequently the length of the util is measured on

  <Desc / Clms Page number 33>

 
 EMI33.1
 along the Y axis while the tool deviation is me1U4Í along the X axis.

   In the present case, for the g1ago of the tool, the device provides an adjustment along two to xooo. To fulfill this mission, the adjustment devices of
 EMI33.2
 wide range of the FW block include, as shown in Figure 13, a row of switches 300 for the X axis and a row 302 for the Y axis. This same correction or modification, in the setting of the Y axis. X, Will. necessary for each of the tools and consequently for% ni revolver lathe having a turret with five tools it will be necessary
 EMI33.3
 No need to have five sets of switches in each row for the X and Y axes, with one set of switches for each turret position.



   A digital / analog converter is already known which provides means for transforming the digital information obtained from the strip for a particular electrical terminal point of a machine element into voltages / analogs in sine and cosine. This control apparatus comprises a number of synchro-devices or decomposers which are connected by gears having different ratios.
 EMI33.4
 with -1 "em" eRta ", of the mobile machine, as shown in FIG. 14 and excited by analog signals rept4 successively sensing the decreasing order digits of the number of the particular terminal point.

   When the signals of and-
 EMI33.5
 reur for all decomposers are simultaneously 0 the desired position has been reached and the movement completed *
 EMI33.6
 Referring to Fig. 14, the illustrated positioning system employs coarse, medium and fine decomposers, 90, 91, 92 which are each connected, to transfer to the movable machine element which is connected. is ordered with different gear ratios. The coarse decomposer 90 is
 EMI33.7
 connected to drive it to the lead screw by sheet metal gears that the rotor turns at the speed of one revolution for 254nRH of displacement of the machine element, it being understood that this is by way of example only ,

   and an addi * decomposer
 EMI33.8
 tional can be easily incorporated and trained in a d.x.téi

  <Desc / Clms Page number 34>

 of the race
 EMI34.1
 / of the coarse decomposer bzz in order to increase the interval of movement of the carriage :. 0 * on the other hand, the rotors of the middle and fine decompcurs, 91, 92s are joined to drive it to the lead screw so that they turn respectively at
 EMI34.2
 Speeds of one revolution for 15.4mu and one revolution for 2.54mm of displacement of element 64.

   Since it is preferable to limit the total displacement of this
 EMI34.3
 part of the machine so that the shaft of the coarse decomposer 90 cannot make more than half a revolution, because this decomposer provides a zero for two positions
 EMI34.4
 rotor angles spaced Ï8Q *, the interval of movement of this machine element, with the apparatus
 EMI34.5
 with three decomposers represents, is l2xmri. It will easily be understood that with an additional decomposer this interval will be increased to 127Omnt and with two decomposers to 1.i0Cnt.



   In numerical terms, the coarse decomposer 90 gives a solution up to the nearest tenth of 2 $ mm4, the average decomposer 91 up to the nearest hundredth
 EMI34.6
 of 2S, 4m.rtl and the decoïttoser end 92 until the thousandth the closest of 25.4m. In practice, additional decomposers can and are generally added so as to keep
 EMI34.7
 account for dimensions greater than 127mm and allow further fine adjustments
To be compatible with other portions of the system, the wide-gap adjusters W, shown at
 EMI34.8
 Figure 13, include means for raising and ecxaa * gasàner a number four intoxicated.

   A number of sets of independently actuable cosNMtators in two rows 300 and 302 are provided for wide interval adjustments, each set comprising four sets.
 EMI34.9
 switches 5 \ 01..1 to S "4 With these switches the units of the position modification are marked using the first switch 1, the tenths of units are '3, the second switch 2, the hundredths using the

  <Desc / Clms Page number 35>

 
 EMI35.1
 switch 3 and the desired settings at the nearest 1lo of the unit are obtained by using the switch4t, 4.I first set of switches $ W-2 to $ W-4 are raised to store a number I modifier 0.678 for example .

   The upper switch SW-1 is raised in its zero position "> the tenths switch SW <? is lP1a in the "six" position, the hundredths switch SW-3 is set to the "seven" position and the 3 il licmes switch SH-4 is set to the "eight" position,
 EMI35.2
 Following this method of the i44w decomposer. Sky to modify the data of the terminal point read in a particular data block of the tape, the corresponding digital information;

   to a Terminal position modification recorded in the previous way in a set of
 EMI35.3
 four switches is combined in the d1ff '' rential RD decomposer with the analog electrical signals (voltage in sine and cosine) obtained by conversion from
 EMI35.4
 of this information provided by the digital tape. In accordance with the present invention, wide range settings can be made for separate machining phases or for a series of phases and the information read from the web is used to choose the wide setting. interval
 EMI35.5
 desired in those that have been stored.

   Danp this purpose means are provided for choosing a particular set of 'switches $ Wl PW <'4 for one or more particular machining phases. As shown in Figure 13, the signal from the data block on the tape which designated the turret position is used to designate a set of switches corresponding to that turret position. we plan to ef-
 EMI35.6
 Shaking rulers at wide intervals along 4q different axes, Means are also provided for choosing
 EMI35.7
 a set of switches either from row 300 of t4.

   of the X axis, or row 302 of the Yb axis switches depending on whether the direction for a

  <Desc / Clms Page number 36>

 particular terminal position should be measured along the X-axis or along the Y-axis. In other words, it is possible to choose between the X-axis adjustment switches 300 or adjustment switches
302 of the Y axis, in addition to choosing a particular set of five possible sets and the selected switches are used to modify the data programmed for the end point.



   A negative switch SM is also provided for each set of switches SW to further increase the adjustment interval. This SM negative switch allows adjustment in either direction along each of the axes. These negative switches are connected, as has been shown, to a negative relay MR.



   Still referring to figure 13, to apply the above, turret position relays
TPR are provided in association with each of the sets of switches in row 300 of the X axes, and in row 302 of the Y axes, respectively. These TPR turret position relays are energized in accordance with the position of the designated turret. from the tape data.

   In addition, an XAR adjustment relay for the X axis is associated with the row 300 of switches of the X axis, and a relay for the back Y axis, YAR is associated with the row 302 of switches of the X axis. the Y axis. Each data block of the tape contains, in accordance with the present system, information designating the axis along which terminal [the position / must be measured so that the input reader A produces a signal which will designate, from the tape , which of the XAR or YAR adjustment relays should be chosen.

   By energizing either the XAR relay or the YAR relay, a potential source will be brought together, via the XAR-C or YAR-C contacts to the input conductors.
306 'and 308, exciting one of the switch banks of

  <Desc / Clms Page number 37>

   x axis or y axis. In addition, following the Signal
 EMI37.1
 turret position switch emanating from drive A, one of the turret position relays TPR-1 to ÏPR-5 setfa energized to close this contact and connect energized input leads 306, 308 to a set of switches.



   Each switch in a SW-1 through SW-4 set provides means for manually raising a square from a four-position number and it has been shown here as a ten-position switch having ten contacts to provide means of noting. and store any number from 0 to 9. Each of the switches can be set manually
 EMI37.2
 in one of these positions.

   The ten contacts of each c <M) MU '* tateur are connected respectively to ten groups of lines 310-1 to 1t4, as shown in figure J.3 <The ten-row group 310-1 connected to switches SW # 1 rather than row 300 of the x-axis, for example, is connected by the numbered switch SW-1 of the corresponding set of row 302 of the x-axis. Y. A group of ten lines 310-2.



  310-3, 310 * 4 is likewise connected by the switches of
 EMI37.3
 each set for the row of Xs to the switches ccrstr y dant to the row of Y. To each of the ten-row groups 310-1 to 310-4 is connected a bus group 312-1 to 312-4 which, in the diagram of figure 13 descends to connect to the digital relays shown in association with the circuit of the differential decomposer of figure 15. With this arrangement there are four groups of ten omnibuses 312-1 to 312-4, one group of ten omnibuses to transmit
 EMI37.4
 each digit of a four-digit modular installation stored in a set of switches SW1, SW.

   A four-place or four-digit terminal position modification instruction will accordingly be transmitted to the differential decomposer circuit by four energized buses with one energized bus, each of the four groups 312-1 through 312-4 representing one bus. digit in the number of four-digit changes.

  <Desc / Clms Page number 38>

 



   For each decomposer 90, 91, 92, a digital to analog converter is used. Each converter provides analog signals representing two digits of an instruction for a four digit end point.



  Thus in an apparatus like the one described involving three decomposers (coarse, medium and fine) 90,91,92 the instruction for the end point emanating from the tape has the form of a four-digit number and the coarse decomposer receives analog signals from a converter which represent the desired position or instruction for the machine element following the two highest order digits of that four-digit decimal number.

   For example, for the instruction 31.3436mm, the first decomposer will give a zero signal for a roter position representing 31.3mm, i.e. an angle of 12/100 x 360 = 43.8. your analog voltages in sine and cosine, after resolution will provide a voltage vector corresponding to this angle. Likewise, the average decomposer 91 receives analog signals from the average digital / analog converter representing the desired position for the element of the machine, in accordance with the second and third digits considered in decreasing order.

   The fine decomposer is fed by analog signals coming from the fine converter following the third and fourth digits. With a four digit number representing the desired position of element 64 and having the value of 31.3436 as noted above, coarse sync 90 will give a zero output signal based on coarse number 31.3. Sync devices 91 and 91 will provide zero repeat signals based on the digital values 0.34 and 0.036 respectively. It should be understood that each of the decomposers 90, 91, 92 of FIG. 4 is connected to transmit its error signal, to the discriminator

  <Desc / Clms Page number 39>

   correspondit, 94 or 95 or 96.

   These discriminators are: constructed and arranged to provide a response dead band or zero point, and in the operation of the control system, zero points are produced successively in the coarse, medium and fine decomposers as the machine element moves to the end point, A zero point will be reached first in the coarse decomposer when the distance to the end point enters its response dead band and the machine element is found.
 EMI39.1
 vera changes in the operating interval of the average decomposer. When the average deoomoser gives a zero, z. ' of the machine element is within the operating range.
 EMI39.2
 operation of the fine decomposer.

   As indicated above, means are provided for slowing down the speed of advance of the machine element when it is approaching the end terminal point, so that this machine element. slides slowly towards the end point until the fine decomposer produces a zero point which, through the control circuit, causes the machine element to stop. Since this slowdown characteristic will be the same with the current system, the discription will not be repeated.



   In the operation of the system for wide-interval adjustment, the magnitudes of the digits of the order
 EMI39.3
 the highest of the modify statement are 4a: u1ti.r. ' digital by the state of 1: e1ai8 gi; DR. The contacts for these DR relays are in the differential decomposer circuit which has the effect of combining the signals from the tape and the modify instruction. Likewise, digital
 EMI39.4
 relay "'uR for the middle decomposer and for the de * dialer end transmit the digits of the modification instruction to the transformer circuitsUr-B representing a differential decomposer associated with the channels for the ° daom.

  <Desc / Clms Page number 40>

 



  Hence, the operation of the decomposers to produce zero points and consequently for diri. Maintaining the movement of the machine element is not changed and is at the same time, as previously described in connection with the operation of the control system for small size adjustments.

   If we take for example a terminal point designation of 31, 3.436 m / m, the sine and cosine voltages from the digital / analog converter can be represented as the vectors SC in figure 17, for the digits. of the highest order, ie 31.3; these SC vectors produce a resulting field vector I.

   With this method of the differential decomposer to modify this instruction for the terminal point, the magnitudes of the voltage vectors in sine and cosine SC, are modified by the differential decomposer RD according to the number of settings, so that the angel Ó of the vector resulting 1 is replaced by a new angle Ó 1 which represents the modified endpoint. Referring to Figure 17, the resulting vector 1 is replaced by vector II by subtracting C1 from the cosine voltage vector and adding S1 to the original sine voltage vector.

   Thus the analog electric voltages representing the instruction for the location of the terminal point emanating from the tape are combined with the signals emanating from the regulator and the resulting sine and cosine voltages are supplied to each decomposer. so that the field vectors of the decomposers represent in analog form the instructions modified for the position.



  Zero voltages will then be produced by the decomposers at the modified end point.



   If we now examine in detail the decompo-

  <Desc / Clms Page number 41>

 Beur differential RD it will be noted that a circuit representing this device is illustrated by FIG. 15. Being. Since a differential decomposer RD must be provided in each of the channels going to the decomposers, coarse medium and fine, 90, 91, 92, for simplicity in the description, there is shown in FIG. 15 the decomposition. differential sor for the coarse decomposer but it should be understood that the same device will be provided for the other decomposers.



   The circuit in Fig. 15 is shown as receiving on the left side of the circuit the signals from the band which come from the coarse digital / analog decomposer through the sine and cosine voltage conductors 314, 316, respectively, and through a conductor. - common tor 318.

   On the left side of the circuit are shown the output voltage conductors 320 and 322 for the sines and cosines and the common conductor 318 which transmit the analog and sine and co-sine voltages to the coarse decomposer 90. Above the circuit, we have shown the digital relays DR representing the two digits of the highest order of the modifying instruction which are energized by the two omnibus groups 312-1, 312-2, from the storage switches - setting selection ge for a wide range.



   The part of the analog sine voltage transformer circuit receives, as input voltage across conductor 314 and common conductor 318, an AC voltage representing the analog sine voltage for the two coarse places of the defining number l 'terminal point position instruction.



   This voltage can be represented by
A1 = E sin wt sin

  <Desc / Clms Page number 42>

 
The output signal of the part of the circuit relating to the analog sine voltage represents the modified sine voltage which is sent to the sine winding of the coarse decomposer 90. This output voltage can be expressed as!
A4 - E1 sin wt win (Ó- 01 - 02).



   The part of the circuit relating to the analog cosine voltage similarly receives an input voltage between conductor 316 and common conductor 318 representing the analog cosine voltage for the two rough places of the number defining the position instruction of the end point. This tension can be expressed by
B1 = E sin wt cos [alpha]
The output of this part of the circuit is sent to the cosine winding of the coarse decomposer 90 and can be expressed as! :
B4 = E1 sin wt cos ([alpha] - 01 - 02).



   To provide wide range adjustment of the end point position in either the positive or negative direction, a negative switch SM is provided and will be associated with each Wide Range Adjustment Switch Set. SW-1 through SW-4, as shown in figure 13. These switches operate an MR relay which has normally closed contacts MR-1, la-4, and normally open contacts MR-2, MR. -4, at the input of the differential decomposer so that when the negative switch is closed the modification instruction will be subtracted from the endpoint position indication provided by the tape instead of being added to it as this is the case when the negative switch SM is not closed.

   To obtain this result, the switching network on the side of the input of the differential decomposer was designed to cross the

  <Desc / Clms Page number 43>

 input conductors 314, 316, as shown.



   The parts relating to sine and cosine voltages of the transformer circuit are arranged in the same way. Each part comprises a first transformer 324-325 whose primary winding receives the input voltage and provides means for producing or deriving an alternating voltage which is a trigonometric function fixed in advance d an angle itself a function of the highest order digit of the modifying positioning instruction.

   For this purpose the primary winding taken is distributed in a nonlinear fashion at five points to produce voltages representing steps of 36 and which can be represented as follows:
For the part concerning the sine voltage:
A2- E sin wt sin Ó cos (18 + 8.), (With 01 in steps of 36 depending on the digit of the highest order).



   For the part concerning the cosine voltage *
B2 = E sin wt cos [alpha] cos (18 + 01).



     If, for example, the highest order digit is "a" and if the next lower order digit is "B" the omnibus group for these digits will have ten relays and that of a0 to a9, one of which will be excited to represent the size of the digit. The taps on the primary winding of the first transformer are connected to ao-1 as shown, by the contacts ao-1 / from relays 1C to a9 so that the magnitude of the angle 01 in the given expression higher for A2 or B2 will be adjusted in steps of 36 according to the number a of the higher order.



   This voltage or B2 is transmitted to the central tap of the secondary winding of a transformer as shown. In this circuit the first transformer 324 in the part of the circuit relating to the sine voltage has a secondary winding 32-S for the part of the cosine voltages. Likewise, the

  <Desc / Clms Page number 44>

 first transformer 325 has a parallel 325-S winding for the sine voltage part.

   The secondary windings / provided with linearly distributed taps and provided with connection going to the contacts of the relays of number "a" of the highest order, so that the voltage at point A3 will be a sum of the voltage A2 and a voltage which is a trigonometric function set in advance of the input cosine voltage which corresponds to the highest order digit "a".



   A3 can be expressed as follows:
 EMI44.1
 Ag A2 - "I sin (18 + 0 1) A3 - B sin wt sin CaC- (1t3 + 81) J.



   The tension at point B3 in the cosine voltage section will be *
 EMI44.2
 B3 B2 + A1 sin (18 * z- 81) B3 = E sien ut cos Ld-- (. $ + 8x) The voltages P ,,, and B3 are connected, as shown, with the secondary windings of the transformer . The primary windings 326 -P, 327 - P for the secondary winding of transformers 326-S, 327-8 are found in the other sections.

   These secondary windings 326-S and 327-S are provided with taps linearly distributed to represent steps of 3.6 and the outputs are connected to contacts bo-1 up to b0-9 associated with the relays of the number close to l 'highest order b0 to b9 so as to produce at point A4 an output voltage which can be expressed as follows:
 EMI44.3
 A4 A3 + B3 tan (18 - 62) A 4 E sin wt sin (OC - 8 - 9z). with 02 in steps of 3.6 in accordance with the figure next to the highest order.



   The voltages in B4 are as follows:

  <Desc / Clms Page number 45>

 
 EMI45.1
 B4 B3 - A3 tan (180 - e2) B E2 sin wt cos (of- 91 - e 2 with 02 in steps of 3.6 depending on the digit of the highest order.



   If it is assumed that a strip has been prepared for the series of machining operations for a vertical revolver lathe such as the machine tool which has been shown in Figure 1, the operator will first proceed as a 'testing these operations / setting up wide-interval settings for the tool in the first turret position and then, using the short-distance setting device, as described, on setting for each of the phases which are executed with these tools so as to obtain extremely precise adjustments for each end point.



   For example with a boring bar in position in the turret, the operator will move this bar horizontally to a first end point, in a position where it is above the workpiece.



  This will be an automatic operation which takes place under the control of the band. At this first terminal point the cutting edge of the tool will be at a known distance from the surface of the workpiece. However, if it is assumed that the tool is shorter than the programmed tool length, with the present system, the operator will lower the bar to the desired height which will be a measured distance.

   If it is also assumed that the horizontal distance of the tool on the X axis is greater than that foreseen by the programmer, the operator will slowly move the carriage the desired distance, to the right of the figure. 1. The distances on the X and Y axes by which the operator has moved the tool constitute the "wide interval" settings which should be taken into account when performing repeated machining operations. with the tool in the turret in the position * shown.

  <Desc / Clms Page number 46>

 



   The current system achieves this result as follows:
The operator places and stores in the first set of switches SW-1 to SW-4 (corresponding to the position of turret 1) of row 300 of the X axis the quantity by which the tool has been moved along the horizontal X axis. Likewise the Y axis adjustment is made in the first set of switches SW-1 through SW-4 in row 302 of the Y axis. These operations can then be carried out repeatedly with the same settings for each operation relating to the tool in position 1 of the turret.



   If it is desired to provide means for vigorously and automatically indicating to the operator the particular switches, among the wide interval setting switches which must be in place to obtain the desired setting, these means are easy. to be established as, for example, phase-sensitive devices which fulfill the function of zero indicators connected as seen in FIG. 11 to the circuits of the discriminator. With these devices, after the operator has brought the tool in position 1 of the turret down (Y) to the desired height for that particular tool and in the X direction of the distance horizontal desired, several or all of the zero indicators will give an offset-zero position indication for the associated decomposers.

   This is to indicate that the set switches SW-1 to SW-4 should be arranged to give a zero for the set end point. If the wide gap decomposer is in neutral, this indicates that the operator should move switches SW-1 and SW-2 to a position where the wide gap zero indicator should indicate zero.

   In fact, the highest order digits of the position supplied by the tape and programmed for the

  <Desc / Clms Page number 47>

 end point have been set by adding a modify instruction so that the coarse decomposer will give a zero signal at the cracked end point. Likewise if one of the other zero indicators indicates that the associated decomposers are in neutral, the corresponding switches must be set to the position in which the indicators provide zero.



   The same process will be followed for each of the other turret positions. In some cases this will be the tool length adjustment, in other cases the adjustment will be on the horizontal deviation of that tool and in some cases it will be on both. In addition, for each machining phase, small individual adjustments can be made by means of the Q adjusters to account for tool wear and other small errors which vary for each of the machining phases.

   In this way, the whole machining program can be carried out on a trial basis and the settings over a large interval or a small interval will be stored, so that when the program is repeated fully automatically , the machine tool will bring the various work items to the modified end points according to the recorded modification instructions.



     It should be understood that although the means and the system for the adjustment of the end point have been described in terms of a two-axis system, the principles are applicable to multi-axis control systems without limitation of the number of axes. .



   The method for wide-interval adjustments which comprises differential decomposers for combining the signals emanating from a tape and the adjustment signals which has just been described previously has, as a first objective, to establish in the machine tool a device that allows the operator to check the settings along two axes to adjust the length of the tool and its horizontal offset

  <Desc / Clms Page number 48>

 in all cases. The system shown schematically in Figure 6 shows this method. In this system, the method for making the adjustments at a short distance will also be kept in the form of potentiometers P which have been described previously.

   Thus the control system includes a tool adjustment on two axes as well as a device for making small adjustments for programmed end points. These small adjustments could be made for each of the phases in a program. With the necessary provisions for performing tool adjustment, the same adjustment will apply to all phases when the same tool is used.



   Another embodiment of the invention shown as a control system in Figure 7 applies these principles. In this embodiment, the data from the programmed band is combined with the wide interval adjustment data or modification data in a process step which precedes the moment when the analog signals are transformed into error signals indicating a shift. or a distance to the endpoint. Generally speaking, the present system is similar in its arrangements to the wide gap system which includes differential decomposers.

   The combination of the two numbers which respectively represent the position of the end point and the wide range adjustment, on the other hand, takes place in the present system before the number coming from the tape and representing the position of the end point is converted into analog voltages. From this point of view, the present system represents a variant of the invention with respect to the embodiment using one of the differential decomposers.



   Referring to Figure 7 it is understood in this diagram that the position of the terminal point is read in each data block on the tape by the data reader A and is stored by means of step-by-step relays for the storage of the terminal position. In this case a

  <Desc / Clms Page number 49>

 step relay having two banks of contacts SS-1, SS 2 (figure 16) is associated with each position digit of the terminal point. Four of these relays will provide storage for a four-digit number. Each relay will be driven into a position or state that represents the corresponding number given by the tape drive. When reading a block of data, the reader will move the four relays into the positions representing the position of the end point of that block of data.

   The machine tool elements will be driven to the position of each of these end points before the stored number represented by that position is cleared in these relays and these relays are driven to new positions representing the position of the endpoint for the next information block on the tape. Figure 16 shows a switch with two banks of contacts $ SI for the highest order digit of the number corresponding to the position of the terminal point. With a switch and links, as shown, with relays a0 to a5, a digit of the decimal number characterizing the position of the terminal point is converted according to a biquinary code represented by the state of relays a0 to a5.

   Similar circuits are provided for the other digits.



  The previously mentioned addition of the number for the wide interval adjustment which has been noted in the machine tool with the number defining the position of the end point is effected by an adder circuit S which has been shown in a diagram of block in FIG. 7. With the position of the end point and the wide interval setting both in biquinary code, a relatively simple calculating circuit can act as an adder circuit, as has been described for example on pages 462 to 474 of "The design of Switching Circuits", Keister, ritchie & Waschburn "(1951 Edition).



   Any suitable switch arrangement can be used to set up and store settings

  <Desc / Clms Page number 50>

 at wide desired intervals, for example as in the rows of separate switches 300 and 302 on the X and Y axes, shown in Figure 13 and previously described. Each row includes 5 sets of switches on the panel that has been shown, with one set for each position of the turret. With this arrangement, a separate set of four switches SW1 to SW4, one switch for each digit of a number of settings is provided for each tool mounted on a five-sided turret. Additional switch sets could be inserted if other tools are used or to meet other needs.

   With these systems the machine tool elements will be driven along only one of the two X or Y axes, as shown in figure 1A and the axis designation on the web. will also be used to designate that of the rows of switches which will be used in a given machining phase. This is achieved by energizing either the XAR axis designation relay and closing its XAR1 contacts, or as a Y axis designation relay by closing its YAR1 contacts. Four groups of bus lines run downward in Figure 13 from the switch panel to transmit the setting number noted by the switches. A bus group is provided for each digit of the four-digit setting number.



  The bus lines in each group are numbered from 0 to 9 and the excited line in each group represents the number for the corresponding digit.



   Referring now to figure 16, a group of ten bus lines corresponding to the highest order digit "a" of the setting number is shown at the top of figure 13. This group of dex bus lines is connected as shown to a switching circuit to convert the number entering by the highest order digit into a biquinary code so that this number will be in a form acceptable to the bi adder. quinary S. This circuit includes' relays b0 to b5 which are

  <Desc / Clms Page number 51>

 directly excited: by bus lines 0 to 5 of the group of ten input bus lines. Also included are relays b6 to b9 which have back contacts b6-1 to b9-1 in a parallel circuit connected to relay "five" b5.



   With a bus line of a higher number energized by these means, the "five" relay b5 will be energized. Circuits having a second set of voltage contacts b6-2 to b9-2 represented by B + through a bus line and the "four" relays b0 to b4. In this way, any bus line of higher rank being energized, in addition to relay "five", a relay of smaller rank which is also energized when it has a rank / added to five is equal to the input rank of. the omnibus line. In this way, the state of relays b0 to b5 constitutes, in binary code, the digit transmitted to the circuit by the bus line excited in the group of ten bus lines.



   A similar circuit will be provided for each of the groups of ten bus lines so that each digit of the setting number will be represented in biquinary code.



   The modified Y position of the terminal point coming from the output of the positioning S is then applied to digital / analog converters already known. The highest order digits of a band for the position of an end point are transmitted to a digital to analog converter for the coarse decomposer. Likewise, the lowest order digits are transmitted to a digital / analog converter for the fine decomposer. With a four-digit number, as in the present case, the second and third digits are passed to a converter for the average decora- poseur. The inputs to the converters are in the form of A and B multi-bank stepper switches for two digits.

   To convert the position of the modified terminal point which is presented in biquinary code at the output of the totalizer S into / form which will be accepted for the converters, it is possible to

  <Desc / Clms Page number 52>

 use a "biquinary code to decimal code" converter circuit such as the one shown in figure 16. It will be seen that each digit of the position of the modified terminal point is represented in biquinary code by the state of the relays CO to C5 . The contacts of these CO to C5 relays are arranged in networks 340 to be substituted for the banks, respectively, of the switches.
A and B of the circuits of the digital / analog converters.



   Referring to figure 7, the same totalizer S can be used to add an address obtained from the strip in biquinary code (on any one of the control axes) and the number of settings for the axis which has been chosen by the means described previously in connection with FIG. 13. It will nevertheless be understood that, while FIG. 16 represents only the circuit of the declination code converter into biquinary code for the digit of l The highest order "a", a similar circuit will be provided for the other three digits of a four-digit position.

   Likewise, on the output side of the circuit, a set of six relays provides the digit corresponding to each digit and similar circuits are also provided for the other digits of the four-digit number which could be supplied by the totalizer and which constitutes the sum of the address and the setting. The state of the totalizer output relays represents, in biquinary code, the address of the modified terminal point which is transmitted directly to the circuit of the transformer used for the digital / analog conversion via the contact networks 340 shown in figure 16.

   Thanks to these digital / analog converter circuits, the modified endpoint address is converted into analog sine and cosine voltages supplied to the decomposer for the X or Y axes, depending on whether the axis of movement lies along the X-axis or Y-axis.

  <Desc / Clms Page number 53>

 



   The operation of equipping a machine tool with a control system providing both fine and wide range adjustments has been described in conjunction with the differential decomposer method to combine the analog voltages representing the end point and the data. adjustment. The operation of the machine equipped with a control system; such as that shown in Figure 7 is essentially the same. A programmer will analyze a series of machining operations, using one or more tools, and prepare a web to direct the machine tool in performing these various operations.



  When the turret carries more than one tool, the program, in addition to the data for positioning, point by point, the elements of the machine tool, will include an indication to lead the turret to place the desired tool in the working position . Each information block also includes data relating to feeds and speeds as well as to the choice of method.



   With such a strip in the machine tool controller and a suine piece mounted on the table, the operator will perform a test pass in which each phase of operations is controlled by instructions from the strip. but, at each end point, the elements of the machine tool will stop. This will allow the operator to check if the tool is indeed at the desired end point and to make small adjustments using the D adjusters to correct for any differences that may occur between the actual position and the desired position.



   With the wide range adjustment device described above, the operator can make adjustments for the length of the barrel and for its distance. Thanks to this arrangement in the control system, the operator can program the movement

  <Desc / Clms Page number 54>

 high point in Figure 1A and the X and Y distances for the high point can be noted by the operator for each tool on the turret. When this test run is completed, operations can be automatically repeated under full control of the tape. If the tool needs to be changed or sharpened while machining the workpiece, the wide range setting for these tools can easily be ground.



  Numerically controlled positioning systems have been described above for causing the machine tool elements to move in successive positions, along different axes, in accordance with a program, which must be repeated. , negated in successive positions. These systems have been described in their application to a vertical revolver lathe but it should be understood that these systems can be used with other types of machine tools. With a vertical revolver, the programmed data settings can be made along the vertical axis which in Figure 1A has been called the Y axis.



   Adjustments can also be made in the vertical plane along the conventional horizontal X axis shown in Figure 1A.



   The preceding description related to two forces of realization of the invention, the method of the differential decomposer and the digital addition. In the case, these systems are two-oriented systems (X and Y) as shown in Figure 1A. These systems require elements for each control axis to perform the functions which have been shown in figure 6 or in figure 7.

   Thus when the movement on the Y axis is provided by a sliding door

  <Desc / Clms Page number 55>

 tool able to move vertically, carried by the plate and driven by a lead screw (elements which can be simpler have been omitted in the diagram of figures 6 and 7) the machine element whose position will be determined on the Y axis will be this tool-holder carriage in place of carriage 30. The drive device I will likewise be the device for positioning the slide & in place of the device providing the advance of the carriage.

   For practical reasons it is extremely desirable to use in all cases the same circuits and other apparatus whenever possible In the case of the machine tool of figure 1 which includes programmed movements on the axis of the X and on * the Y axis, a common use of certain elements is possible, such as the "step switches for storing the terminal position" and the "digital-analog retainers, all two in figures 6 and 7, the "decimal code to biquinary code" converters, the totalizer, the digital / analogue converters of figure 7.

   Each lead screw of course includes a separate set of decomposers which have been described here as coarse, medium and strong decomposers 90 to 92.



   In the case of the system shown in Figure 6, the circuits representing differential decomposers can also be assigned to various uses and thus, the X-axis and Y-axis adjustment switches in Figure 13 have been used. shown as connected to common groups of ten bus lines that lead to relays (Figure 15) to provide X-axis or Y-axis adjustments to the differential decomposer circuits. The circuit which represents a differential decomposer for the coarse decomposer path, receives

  <Desc / Clms Page number 56>

 before the two digits of the highest order, a. been described. A similar circuit will be connected to each of the middle and fine decomposers.

   Appropriate connections will be provided so that the decomposers of the X axis or the decomposers of the Y axis are joined to the circuits of the differential decomposers along the axis of movement and control which is in play,
Measurements were taken in the systems shown in Figures 6 and 7 to record in the machine tool both the fine adjustments and the wide interval adjustments.

   It is obvious that these principles can easily be extended to a three-axis system, that is to say that the arrangements either for wide-interval adjustment or for wide-interval adjustment and fine adjustment together. can be included in systems comprising one, two or three axes of movement or control by providing position indicating devices or decomposers for each axis and by providing, for the three axes, the parts of. control circuits which have been shown for two ax axes in Figures 6 and 7.



   A particularly useful application of this three-axis system has been shown in Figure 18; the figure schematically shows a horizontal spindle of a boring machine and the X, Y and Z axes are used as references for this spindle .



  Also shown schematically in Figure 18 is a CP control panel for this machine which has different sections associated with the X, Y and Z axes. According to the present invention, this CP control panel in Figure 18 includes means permitting wide range adjustments on each of the three control axes. This arrangement is particu- larly useful with work facilities

  <Desc / Clms Page number 57>

 
 EMI57.1
 4'Ú.i. tttlwtâttètt. we propose to have 6 ld.o; yèni1 have 6dy control the OP panel to perform tèglétgoë at the interval separated along the X axis.



  In this way, the panel comprises two sets of switching
 EMI57.2
 t & ars of adjustment for the corresponding X axis èëpt4 $ to îement to workstation 1 and to the
 EMI57.3
 work of the axis of the X as it is indicated by the figure lis Each set of switches includes c1J.1q switches to allow the registration of 4tùn n * ab: ro to five. figures.

   With four decomposers, instead of three (as described above) including a decomposed **
 EMI57.4
 grobs1. additional driven to a revolution pouf 2 * 540 taai linear displacement of 11. b: J1oehé Ïo along the 8 days of the xi the adjustment interval along the X-axis can reach up to 1. & 70 tamt for illustration. An interval of 1 "10 b can be achieved by adding another decomposer to the system.
 EMI57.5
 



  These separate streams of decomposers poat the * dMW axis in this case provide means for a x4
 EMI57.6
 De-origilie sliding along the Xâ On and 1 axes of the ôutmi * tators allows the origin to be set to align? the programmed soft births or the electric frame of reference
 EMI57.7
 with 16 effective reference dadile from ì * 4 it 'b is worth * to station 1 while the second set of oomau .. tate0d allows this alignment 1 & .tat1o:

  A 2, bf, With this arrangement the machine tool may be required to execute phases programmed at station 1 with a directiva emanating from the band * In an es-
 EMI57.8
 saij the wide interval setting needed for 1; 1.11-; addition to station 1 can be done, TS tumbler switch On the control panel CI * is said in (Se

  <Desc / Clms Page number 58>

 in position 1 and the setting on switches SW 1 to 5 of set 1 will then be effective. During the period during which the Ébat machining operations carried out under the control of the belt at station 1 * l 'one of the operators can prepare the work at station 2.



     After the part at station 2 has been worked, the operator will move the TS tumbler to position 2 which will cause the setting recorded by the second set of switches to be combined with the data supplied by the tape and move the setting. broached in workstation 2 to produce the same series of machining phases in the new position on the new workpiece.



   To show again how the inventive can be applied, the system shown schematically in Figure 18 comprises, in addition to the original setting along the X axes, means for recording a single setting at wide gap along the Y axes.

   This adjustment along the F-axes could be applied to either workstation 1 or 2 (or any other spindle position along the X-shaft). As an example * this possibility of making adjustments at wide intervals along the Y axes allows the operator to make an adjustment for the thickness of the pallet on which the part is mounted at the work station * On sees that most tuning problems can be solved by the arrangement in which the same tuning will be provided in all x-axis positioning cases and thus no means are needed to achieve different settings for

  different phases or for different locations, as in the case of controls on the x axis.

  <Desc / Clms Page number 59>

 



   The system of Figure 18 will also include adjustment means along the Z axis. In this case these means take the form of a back adjustment.
 EMI59.1
 wide gap for tool length Thus J, 1 operator, using 1% switches can enter distances which need to be added. (or subtracted) at the end points programmed * on, - the Z axis. In addition, to allow different settings for different implements, a number of rows of Z set switches are included, and have
 EMI59.2
 been represented in the particular case Pin $ of ' <1 these rows.

   As in the systems of figures $ and 7,
 EMI59.3
 means make it possible to choose a row partc.-1 of switches for the Z axis for u4 tool putO \ 1. ". link. If, for example, a tool change ttta'4t ,; has been planned and if more than 5 tools are included in the machining program, it will be necessary to use more than
 EMI59.4
 five rows of switches for axis 4 a 2 a1 eu | ÇwÇ | can be easily added, In the pressai case, 5 rows of switches represent this device of separate switches that can be chosen,

    from the band following the data on that * band so that a particular pre-adjustment is automatically combined with the band data for the end point for the Z axis control.
 EMI59.5
 



  Particular emphasis was placed on the CP command pagniag and the separate command sets for the X, Y and Z axes on this panel. We have described
 EMI59.6
 çtX & et # aa. how this system was built 0't mew, tallé. It is understood that, in agreement with 1 4voo law qr vention, the system can follow either the method dl -clbq4 differential setter to combine the data of 7.tt 'and the data emanating from the tape, or the method

  <Desc / Clms Page number 60>

 addition of digits or an equivalent method.



  Referring to figure 6 if the system is built according to the method of. differential decomposer, each of the X-axis, Y-axis or Z-axis systems will include components to perform the different functions designated in the "4-step step switches for storage" blocks
 EMI60.1
 of a terminal position "," digital / analog converters. 1 giquo ", ndifferential decomposers", decompose "discritainatettrs", and the associated drive 0yen9 to position the machine elements along the axis of movement particular.

   Whenever possible, the same apparatus will be used to perform the same function in different parts of the system. Thus in systems in which the programmed movement takes place along only one axis at a time, the step-by-step switch memos can be used to store the end position regardless of the control axis. which will be provided with the appropriate connection to link the step-by-step switches to the active setting switches on the CP control panel,
In addition, in the case of tool adjustment on the Z axis,

   the member referred to as "storage device for wide range selection" provides a means for selecting the particular row of Z-axis adjustment switches. It will be understood that if one has provided no fine adjustment, no component will be needed to perform the functions of storing selected adjustments and adjusters.



   If we refer to figure 7 in which the method of adding figures is applied, the system comprises, for each control axis as in the previous case, members to fulfill the functions

  <Desc / Clms Page number 61>

 
 EMI61.1
 of "CcM # utatoura not for the. # masa'è of positions tèttimaoalit of" d'COf.l1: poaeutl "and" 4iscr1mL- 1 ',' d41. "dt 0 ce s; 1'l! Jtè # .e cClUlpr.nd.r-.1t moreover the 'Ctl'9r weavers of decimal code in biquina1 code' "t '# totali * oeurn, 4 # and" d1git.l-analogft converters. Anytime. the same equipment can be used by different circutis, the effeotivee realizations of the invention can be chosen to take advantage of this arrangement *


    

Claims (1)

- CLAIMS- Having thus described the braided invention, reserving the right to make any improvements or modifications which we would seem necessary) we claim as our exclusive and private property: 1 - In a Command pouf system, the positioning of a mobile element of a machine tool according to a program which must: to be repeated, the combination which includes an element mounted to be able to move, a device for bringing this element into successive Positions, a reader obeying successive blocks of information which are supplied to create successive sets of position indicating signals which indicate the positions debited for said element, a control device receiving case games. position indicating signals and connected to the device which moves the element to cause the latter to bring said element into the corresponding positions and means for modifying the operation of this control device which comprise a source of regab signals; the and means for applying the friendly signals, by this source to said control device in such a way that said element is caused to move up to a position which deviates from that which has been designated by a set of position indicator signals ; in accordance with the corrected output sigusl transmitted from said signal source. 2 '- Apparatus according to 1, characterized in that a certain number of adjustable signal sources are provided. 3- Device according to 1 and 2, characterized in that the adjustable signal source or sources apply to a certain number of commands. along one or more axes. <Desc / Clms Page number 63> 4. Next device 1. characterized by the fact that it comprises a number of adjustable singal sources, a reader for creating successive sets of position indicating signals and for creating selection signals codes according to at least some of these blocks, means obeying to each of these election signals encoded to choose one of these sources which will be effective during the positioning of said element, in accordance with the set of position indicating signals corresponding, so that said element is caused to move it until a position which deviates from that which has been designated * by a set of position indicating signals) according to the corrected output signal from the selected signal source. 5 - Apparatus according to 3, characterized in that there is provided a certain number of sets of correction device, at the rate of one play for each control axis and means for selectively acting, a determined set of these devices correction, according to the reading of a determined block, on the influenced recording means. .., L by the data in the block designating a particular corresponding control axis, 6 - Next device 1 to 3, characterized by the fact that it comprises means for additional the signals collected in a block by said reader with the adjustment signals and for converting the sum into signals representing the desired position modified along an axis, a source power to move said element, das means for comparing these signals representing the stove. modified with the current position of said element so as to deduce therefrom an error signal indicative of the position error and a, control device which comprises means for receiving said error signal connected to the power source to cause the latter to move said element until this error signal is reduced to zero, <Desc / Clms Page number 64> 7 - Apparatus according to 1 to 3, characterized in that it comprises means for converting the signals supplied by the unit to the reader into electrical analog signals representing the original position desired along one of these axes, means comprising a differential decomposer for transforming said electrical analog signal into an output signal of a signal source to provide modified electrical analog signals representing the modified desired position and a controller capable of receiving these signals from the position Modified connected to the power source to cause the power source to move the element to a position away from the original desired position in accordance with the adjusted output signal from the signal source. 8 - Apparatus according to 7, characterized in that it comprises decomposers that can be influenced by the current position of said element to compare the analog signals representing the desired modified position, with the current position of said element and to deduce an error signal therefrom indicative of the position and a control device capable of receiving said error signal, connected to the power source to cause the latter to move said element until this error signal is reduced to zero. 9- Apparatus according to 1 to 3, characterized in that the apparatus comprises a reader producing a digital signal representing a desired original position,. one or more adjustment devices for producing a digitally shaped signal representing the magnitude of the adjustment (s) to the desired original position (s), means for adding the digitally shaped signals from the block emanating from the reader with the control signals in digital form and to convert the sum into analogue electrical signals representing the desired position modified along one or more axes, <Desc / Clms Page number 65> and a controller connected to said power source for causing said element to move to a position away from the desired original position along one or more axes, depending on the adjusted output signal from the or adjustment devices. 10 - Apparatus according to 9, characterized in that it comprises means for comparing the signals representative of the position modified with the current position of said element along one or more axes in order to deduce therefrom an error signal indicative position error and a control device for receiving this error signal, connected to the power source to cause the latter to move said element until this error signal is reduced to zero . 11 - Apparatus according to 1, characterized in that it comprises means for comparing the modified signals representing the position with the current position of said element in order to deduce therefrom displacement signals indicative of the displacement distances to these desired modified positions and a control device for receiving these displacement signals, connected to the power source to cause the latter to move said element until these displacement signals are reduced to zero and said element is brought into said modified desired position.