US3898440A — Size control apparatus for machine tool

Claim 1

Independent Claim 136 words

A size control apparatus for a machine tool comprising: a first measuring means provided at a machining station for measuring a workpiece under the machining operation of said machine tool and for controlling the operation of said machine tool in accordance with a size of the workpiece, a second measuring means provided at a measuring station separate from said machining station for measuring a workpiece already machined, a calculating device responsive to said second measuring device for calculating an estimated value to be obtained for an unprocessed workpiece depending upon information obtained from machined workpieces and for producing an instruction signal as the result of comparing said estimated value with a first predetermined control limit, and a compensating device capable of modifying the control operation of said first measuring means in response to said instruction signal.

Claim 2

Dependent Claim 136 words

A size control apparatus for a machine tool comprising: a first measuring means provided at a machining station for measuring a workpiece under the machining operation of said machine tool and for controlling the operation of said machine tool in accordance with a size of the workpiece, a second measuring means provided at a measuring station separate from said machining station for measuring a workpiece already machined, a calculating device responsive to said second measuring device for calculating an estimated value to be obtained for an unprocessed workpiece depending upon information obtained from machined workpieces and for producing an instruction signal as the result of comparing said estimated value with a first predetermined control limit, and a compensating device capable of modifying the control operation of said first measuring means in response to said instruction signal.

Claim 3

Dependent Claim 59 words

A size control apparatus as set forth in claim 1 wherein said calculating device includes data storage means capable of memorizing a predetermined number of data concerning workpiece size measured by said second measuring means and capable of eliminating data in excess of the predetermined number so as to calculate said estimated value depending upon the most recent data.

Claim 4

Dependent Claim 11 words

to calculate a trend in said predetermined number of measured values,

Claim 5

Dependent Claim 11 words

to calculate a trend in said predetermined number of measured values,

Claim 6

Dependent Claim 8 words

to derive an estimated value from said trend,

Claim 7

Dependent Claim 8 words

to derive an estimated value from said trend,

Claim 8

Dependent Claim 87 words

A size control apparatus as set forth in claim 1 wherein said calculating device is operable to execute the compensation when a value which is determined by said estimated value and a first predetermined value exceeds said first control limit to obtain a compensating amount by subtracting a second predetermined value from a difference between the estimated value and a second control limit to output said compensating amount as said instruction signal to said compensating device so that hunting in said size control apparatus may be prevented.

Claim 9

Dependent Claim 19 words

to determine the necessity of compensation as a result of comparing said estimated value with a first control limit,

Claim 10

Dependent Claim 19 words

to determine the necessity of compensation as a result of comparing said estimated value with a first control limit,

Claim 11

Dependent Claim 69 words

A size control apparatus as set forth in claim 3 wherein said compensating device includes: a modifying means for modifying an input from said first measuring means by said compensating amount from said calculating device and transferring a modified output, and a signal generatiNg means for generating an operating signal for changing the operation of said machine tool when said modified output coincides with a predetermined value preset therein.

Claim 12

Dependent Claim 96 words

A size control apparatus as set forth in claim 1 which comprises a detecting device for counting the number of the machined workpieces which are between said machining and measuring stations and for supplying said detected number to said calculating device, said calculating device being operable to supply an initial compensating amount to said compensating device when said estimated value first exceeds said first control limit and, thereafter, to supply a differential between presently and previously estimated values as said instruction signal to said compensating device until said compensating value is reflected in said measured value.

Claim 13

Dependent Claim 40 words

to calculate a compensating amount based upon said estimated value and a second control limit when said compensation is necessary, a compensating device capable of modifying the control operation of said first measuring means in response to said compensating amount.

Claim 14

Dependent Claim 40 words

to calculate a compensating amount based upon said estimated value and a second control limit when said compensation is necessary, a compensating device capable of modifying the control operation of said first measuring means in response to said compensating amount.

Claim 15

Dependent Claim 165 words

A size control apparatus for a machine tool comprising: a first measuring means for measuring a workpiece under the machining operation and for controlling the operation of said machine tool in accordance with the size of the workpiece, a second measuring means for measuring an already machined workpiece, a memory device for successively memorizing the measured values from said second measuring means in an order of measuring operation, a processing device operable to obtain a tread from a predetermined number of said measuredvalues memorized within said memory device and to ascertain an estimated value for the workpiece to be next machined depending upon said trend, A judgement device for generating a compensating instruction as the result of comparing said estimated value with a first control limit, a calculating device for calculating a compensating amount corresponding to said estimated value in response to said instruction, and a compensating device capable of modifying the control operation of said first measuring means in response to said instruction signal.

Claim 16

Dependent Claim 165 words

A size control apparatus for a machine tool comprising: a first measuring means for measuring a workpiece under the machining operation and for controlling the operation of said machine tool in accordance with the size of the workpiece, a second measuring means for measuring an already machined workpiece, a memory device for successively memorizing the measured values from said second measuring means in an order of measuring operation, a processing device operable to obtain a tread from a predetermined number of said measuredvalues memorized within said memory device and to ascertain an estimated value for the workpiece to be next machined depending upon said trend, A judgement device for generating a compensating instruction as the result of comparing said estimated value with a first control limit, a calculating device for calculating a compensating amount corresponding to said estimated value in response to said instruction, and a compensating device capable of modifying the control operation of said first measuring means in response to said instruction signal.

Claim 17

Dependent Claim 44 words

A size control apparatus as set forth in claim 6 wherein said processing device serves to ascertain said estimated value from a trend which is extended from the past to the present and to the future based upon said predetermined number of measured values.

Claim 18

Dependent Claim 52 words

A size control apparatus as set forth in claim 7 wherein said judgement device generates said compensating instruction when a value determined by said estimated value and a first predetermined value exceed said first control limit, said first predetermined value being defined in relation to the standard deviation of said measured values.

Claim 19

Dependent Claim 45 words

A size control apparatus as set forth in claim 8 wherein said calculating device is operable to obtain said compensating amount by subtracting a second predetermined value from a difference between said estimated value and a second control limit when said compensating instruction is generated.

Claim 20

Dependent Claim 72 words

A size control apparatus as set forth in claim 9 wherein said machine tool is a grinding machine comprising: a wheel head provided with a grinding wheel for machining a cylindrical workpiece, a feed mechanism for moving said wheel head toward and away from said workpiece, and a feed control device for controlling said feed mechanism and for determining the advance position of said wheel head in response to said compensating device.

Claim 21

Dependent Claim 85 words

A size control apparatus as set forth in claim 6 which further comprises: a detecting device for counting the number of buffer workpieces which exist between said first and second measuring means and for applying the number of said calculating device, said calculating device being capable of transmitting a differential between presently and previously estimated values as a compensating amount derived from each buffer workpiece to said compensating device until an initial compensation depending upon said compensating amount is recognized by said second measuring means.

Claim 22

Dependent Claim 69 words

A size control apparatus as set forth in claim 11 wherein said detecting device comprises: a first detector for detecting the Machined workpiece exiting from a machining station, a second detector for detecting the machined workpiece which will enter a measuring station, and a reversible counter operable to count up and down in response to said first and second detectors and to transmit its content to said calculating device.

Claim 23

Dependent Claim 54 words

A size control apparatus for a machine tool comprising: a first measuring means for measuring a workpiece under the machining operation and for controlling the operation of said machine tool in accordance with the size of the workpiece, a second measuring means for measuring the machined workpiece at a measuring station, a digital computer

Claim 24

Dependent Claim 54 words

A size control apparatus for a machine tool comprising: a first measuring means for measuring a workpiece under the machining operation and for controlling the operation of said machine tool in accordance with the size of the workpiece, a second measuring means for measuring the machined workpiece at a measuring station, a digital computer

Claim 25

Dependent Claim 42 words

A size control apparatus as set forth in claim 13 wherein said digital computer instructs said compensation when said measured values obtained from the machined workpieces are beyond one of said control limits more than a predetermined number of times in succession.

Claim 26

Dependent Claim 34 words

A size control apparatus as set forth in claim 13 wherein said digital computer is adapted to calculate the deviation of said measured value and to determine said control limits according to said deviation.

Claim 27

Dependent Claim 37 words

A size control apparatus as set forth in claim 15 wherein said digital computer starts the calculation of said compensating amount when a value determined by said estimated value and said deviation exceeds said first control limit.

Claim 28

Dependent Claim 41 words

A size control apparatus as set forth in claim 16 wherein said digital computer obtains said compensating amount by subtracting a second predetermined value from a differential between said estimated value and said second control limit in calculating said compensating amount.

Claim 29

Dependent Claim 56 words

A size control apparatus as set forth in claim 13 which further comprises: a detecting device for counting the number of buffer workpieces which exist between a machining station and said measuring station and for applying the number information to said digital computer to cause said computer to execute a specified processing for said compensating amount.

Claim 30

Dependent Claim 53 words

A size control apparatus as set forth in claim 18 wherein said specified processing is executed so that a differential between presently and previously estimated values is determined as a compensating value derived from said buffer workpieces and said differential is supplied to said compensating device each time each buffer workpiece is measured.

Annuity Stage	Window Opens	Payment Deadline	Surcharge Period Until	Estimated Fee	Status
3.5 Years (Year 4)	1978-08-04	1979-02-03	1979-08-05	$2000.00	Window Closed / Lapsed
7.5 Years (Year 8)	1982-08-04	1983-02-03	1983-08-05	$3760.00	Window Closed / Lapsed
11.5 Years (Year 12)	1986-08-04	1987-02-03	1987-08-05	$7700.00	Window Closed / Lapsed

Size control apparatus for machine tool

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