Note : Les descriptions sont présentées dans la langue officielle dans laquelle elles ont été soumises.
The present invention relates to methods of input-
ting positions of displacement in an apparatus Eor moving
bodies, and particularly to a method of inputting positions
of displacement of a tool and a work into a memory of control
means for controlling -the tool and the work in a boring
machine, a milling machine, a lathe or -the like.
An invention relative to a me-thod of detecting
positions of a movable body is described in Japanese Patent
Application N 96524/79 to TO~OTA JIDOSHA KOGG~O KAB~SHIKI
KAISHA and laid open to the public under N 21745/81 on
February 28, 1981.
According to this invention, in a method of
detectin~ positions of a movable body by directly or
indirectly replacing unit displacements of the movable body
with digital pulse signals, a point where the movable body
abuts against and press a stopper provided at a specified
position within the moving scope thereof is made to be a
reference position, a coincidence between a coun-t number of
the pulse signals coun-ted from a reference number determined
by the reference position and a set pulse number corresponding
to a preset predetermined position is detected to detec-t an
arrival of the movable body at the predetermined position,
whereby the position of the movable body is reliably detec-ted,
thereby enabling to provide a method of detecting positions
of the movable body, wherein the assembling the method into
a machine tool or the like is facilitated and the application
of the method thereto is effected at low costs. However,
here, in order to input a preset pulse number corresponding
to the preset predetermined position, it has been necessary
that the movable body is moved to the predetermined position,
a distance from the reference position to the movable body is
measured by use of slide calipers, a micrometer or a standard
gauge, -the data should be inputted and stored in a memory
by use of a digital switch or a key board. However, according
to the above-described method, errors in measurement may
occur, so that the operation i.s not correctly carried out~and
moreover, -the measuring work is complicated.
The present invention has been developed in vi.ew
of the above-described disadvantages and has as its object
the provision of a method, wherein positions of displacement
of a movab]e body can be accurately and readily input-ted
and stored in a memory.
More particularly, according to the present
i.nvention, there is provided a method of storing positional
information of a reciprocable movable body from a reference
position Eor the purpose of a body moving apparatus which
lncludes, pulse generating means for emitting pulse signals
in accordance wi-th a moving direction of the reciprocable
movable body, each of said pulse signals indicating a unit
displacement of said movable body, counting means for adding
or subtracting a number of said pulse signals to or from a
determ.i.ned reference number corresponding to the reference
position and providing a counted pulse number, memory means
for storing a set pulse number, which set pulse number being
set with reference to said reference number and corresponding
to a predetermined position within a range of movemen-t of
said movable body, and means for judging whe-ther said set
pulse number meets with said counted pulse number of said
counting means after said set pulse number is stored i.n
said memory means, to thereby judge if said movable body
is at said predetermined position,
said method comprising the steps of:
moving said movable body to said predetermined
position to provide the counted pulse number corresponding
to said predetermined position through said counting means;
and
storing in said memory means said counted pulse
number as said set pulse number.
The present inven-tion may also be defined as
follows:
A method of storing positional information of a
reciprocab],e movable body frorn a reference position for -the
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purpose of a body moving apparatus, said method comprising:
emittin~ normal or reverse rotation pulse signals
Erom an encoder in accordance with a moving direction of
the reciprocable movable body, each pulse signal indicating
a unit clisplacement oE said movable body;
resetting an updown counter when said movable
body reaches a reference position, for coun-ting said pulse
signals emitted from said encoder during movemen-t of said
movab].e body in a region other than said reference position,
and providi.ng a counted pulse number through said updown
coun-ter;
storing in a memory a set pulse number correspond-
ing to a prede-termined posi-tlon within said region;
comparing said set pulse number, which has been
stored by said memory, with the coun-ted pulse number of said
updown counter to thereby judge if said movable body is at
the predetermined position,
moving said movably body to said predetermined
position -to provide the counted pulse number corresponding
to said predetermined position through said updown coun-ter;
and
storing in said memory said counted pulse number
as said set pulse number.
~he above-mentioned features and objects of the
present invention will become more apparent from the following
non restrictive description of preferred embodiments thereof
taken in conjunction with the accompanying drawings, wherein
like reference numerals denote like elements, and in which:
Figure 1 is a block diagram showing an embodiment
of a machine tool, to which is applied the method according
to the present invention;
Figure 2 is a block diagram enlargedly and
schematically showing a control module and a program module
illustrated in Figure l;
Figure 3 is a block diagram schema-tically showing
another embodiment of the present invention;
Figure ~ is a flow chart showing -the fundamental
operat.i.ons and procedures .in the embodiment shown in
Figure l;
Figure 5 is a flow chart showlng a control flow
in the flow char-t of Figuxe 4;
Flgure 6 is a flow chart showing a manual operation
setting flow in the flow chart of Figure 4; and
Figure 7 is a flow chart showing a teaching
setting flow in the flow chart of Figure 4.
Description will hereunder be given of an embodi-
ment, in which the present invention i.s applied for inputting
the displacement positions of a tool and a work in a machine
tool.
Figure l is a block diagram showing an embodiment
of a machine tool, to which the present invention is applied.
A table for example, not shown, movably holding a work for
e~ample, not shown, in a machine tool 400 is connected thereto
with an encoder 200, which is adapted to replace a displacement
of the table with pulse signals in such a manner that a unit
displacement corresponds to one pulse. The encoder 200 may
be either a rotary encoder for converting a rotary angle
into pulses of a length or a linear encoder for conver-ting
a linear distance into pulses of a length. For example, o~
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pulse is set to 0.1 mrn. Pulse slgnals from the encoder 200
are i.nputted -to a con-trol module 100, which in turn operates
in accordance with a program selec-ted and commanded by a
program module 150. For lnstance, when the proyram module 150
commands an input of a position of the table for transferring
the tool, the control module 100 counts the pulse signals
from the encoder 200 and stores the position of the table in
a memory thereof. Furthermore, when the program module 150
commands a control o~ the machine tool 400, the control module
100 counts the pulsè signals from the encoder 200, and, when
the counted value coincides with a signal of the table position
stored in -the memory of the control module 100, -the control
modu:Le 100 sends a signal to a control panel 300 to operate
a sequence circuit or the like for operating the machine
tool, so that the machine tool 400 can be controlled by the
operation of the control panel 300.
Fig. 2 is a block diagram enlargedly and schematically
showing the control module 100 alld the program module 150
in Fig. 1, in which the control module 100 and the program
module 150 are detachably connected to each other through a
connector 140. The control.module 100 compri.ses: a program
memory 102 for storing a program for controlling; a central
processing unit (hereinafter referred to briefly as "CPU")
101 for successively performing control and calculation in
accordance with the contents of the memory 102; an input~output
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ci.rcuit 106 Eor connecting CPU to ou-tside; and a random
access memory (hereinafter reEerred to brlefly as RAM)
107 :Eor storing data Erom the program module 150, which
can be varied by an user in accordance with uses. CPU 101,
the memory 102, the input/ou-tput circuit 106, RAM 107 and
the connector 104 are connected to one another through an
address omnibus, a control omnibus and a data omnibus 105,
respectively.
RAM 107 is connected thereto with a backup
battery 108, which can prevent the data stored in RAM 107
from disappearing even if a main power source is temporarily
cut off. Additionally, the input/output circuit 106 is
connected thereto with: a counter 130; a direction discri-
minating circui-tl24~(publicly known by Japanese ~tility Model
Application Publication N 8574/77 published on February
23, 1977 to the name of HITAC~I DENSKI K.K.)for discrimi-
nating the moving direction of the table based on a signal
from an encoder 200 for emitting two pulse signals having
a phasic difference of 90 therebetween, the two pulse
signals being emitted, in the case of the reverse rota-tion
of the encoder, in an emission order opposi-te -to that in
the case of the normal rotation of the encoder; an indicator
121 for indicating errors; a timer 122; and an output relay
123 including a semiconductor switch or relay for emitting
a control outpu-t. The program module 150 comprises: an
input/output circuit 151 connected thereto with a connector
140; and indicator 152 connected to the~
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il~pUt/OUtpllt circuit 151., and a ]ceyboarcl 153. The keyboard
153 comprises: a mode selector key for selec-tirly modes such
as a monitor mode, a setting mode and a teaching mode; a ten
~ey; and a control key for controlling -the settings and
write-ins.
Description will now be given of action of the embodi-
rment of the present invention explained in FigsO 1 and 2 with
reference to the flow char-ts shown in Figs. 4 through 7.
Fig. ~ is a flow chart showing the fundamen-tal opera-
tions. A power source for the whole apparatus is thrown~in,CPU 101 starts its operation in Step 11 in accordance wi-th
a program from the program memory 102, advances -to S-tep 12,
stores data frorn the encoder 200 beiny sto:red in RAM 107
immediately before the power is cut off and data showing the
correspondence of the present position of the table to the
position stored and set in a data area of the program mernory,
returns the memory 102 and the input/output circuit 106 to
the state ir~ediately before the power cut, and advances to
Stép 13. In Step 13, CPU 101 judyes -the succeeding object to
be achieved, and, when the program module (P-M) 150 is connected
to the control module 100, advances to Step 15 for judging
the presence of either the initial state where data showing
a point (a table position stored and set) and data showing
the correspondence of the point to the condition Gf the output
relay are not inputted or a moni-tor mode having data previously
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inputted and sto:red and used to monitor whether the machine
tool ~00 i.s operated in conformity wi-th the data or not.
~hell the con-trol module 100 is not connected to the program
module 150, CPU 101 advances -to a control flow 14 where such
a control is made that an output is actually fed to -the control
panel 300 from the output relay 123 in accordance with the
operation of the machine tool 400, and loops the control flow.
~ escription will hereunder be given oE a method of
inputti.ng setti.ng data oE the correspondence o:E the point
to the state of the point ou-tput relay 123 when the control
module 100 is connected to the program modul.e 150.
Firstly, when the mode selec-tor key of the keyboard
153 is selected to a memory clear mode, P~M connection takes
place in Step 13, then CPU 101 passes through Steps 15 and
17, advances to Step 2]. where CPU ].01 selects the memory
clear mode at Step 21, advances to S-tep 22 where C:PU 101
clears a desirable data area as a whole to zero, and re-turns
to Step 13. Subsequently, the mode selector key of the
keyboard 153 is set to a setting mode, the setting mode is
judged in Step 17, CPU 101 advances to Step 108, then to a
manual operation flow 19, and returns to SteLo 13. Nex-t, when
-the mode selector key of the keyboa.rd 153 is selected to a
teaching mode, CPU ]01 advances from Step 13 through S-teps 15
and 17 to Step 18, a teaching setting flow is performed from
Steps 18 through 20, and CPU 101 returns to Step 13.
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Z~5
Subsequently, when the mode selector key of the keyboard 153
is switched over -to a monitor mode to actually operate the
machine tool 400, CPU 101 advances from Step 13 to Step 15,
and further advances to Step 16 where a relay output emitted
based on the correspondence of a distance from the original
point to the table at this time, the preset point and the
state of the output relay outputted from the correspondence
of the preset point to this distance are indicated by the
indicator 152 in the Step 16, and then, CPU ].01 advances Step
14 to perform a control. flow, and returns to Step 13.
Description will. now be given of the manual operation
setting flow with reference to Fig. 6. CPU 101 advances from
Step ]8 to Step 52 to clear the memory, then, advances to
Step 53, where the setting of the control key of the keyboard
153 and the write-in thereof are inputted, advances to Step 54,
where a desi.rable point number is inputted through the ten
keys of the keyboard 153 and stored in R~M 107, and advances
to Step 55. In Step 55, the correspondence of the di.stance
of the point to the state of the output relay 123 (for example,
the output relay 1 is on at Poin-t Nos. 1, 2 and 5 and off at
Point Nos. 3, 4, 6 and 7) is inputted through turning ON or
OFF of the ten key and the control key of the keyboard 153 and
stored in R~M 107, then CPU 101 advanced to Step 56, performs
Step 56, where 1 is added to the initially set Point No.,
then, when it is not the final point, returns to Step 55, the
s
correspondences of the distances of the points to the states
of -the output xelay are successively inputted, which is
repea-ted until the E~nal point is completed, when the final
point is completed, CPU 101 advances from Step 56 to Step 53,
an end mark is written in RAM 107, in Step 59, the original
point, allowable errors and frequency division ratio are set,
and then, CPU 101 returns to Step 13, thus completing the
man~al opera-tion setting flow~ In this manual operation
setting flow, the relationships between Point Nos., which
should necessarily be determined in the settlng stage of a
control sequence and outputs of the switch can be readily
set, however, the distance, another factor, cannot be set in
most cases until a machlne tool is ac-tually operated to move
a tool or a work to a desirable position and measure the
distance, and, in ~eneral, the measurement of the type described
is complicated, and moreover, proves to be inaccura-te in many
cases.
Description will hereunder be yiven of the teaching
setting flow according to the present invention with reference
to Fig. 7.
In Step 18 of the basic routine shown~ in Fig. 4, when
the teaching mode is inputted through the mode selector key
oE the keyboard 153, CPU 101 advances to Step 20. In other
words, CPU 101 advances to Step 82, in which, f~rstly, the
correspondence of Point No. to the state of the output relay
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is inputted to be stored in ~ 107 throucjh the control key
and the ten key of the keyboard 153. At thi.s time, data of
distance is not set because it is sought through the teaching
operation. Subsequently, CPU 101 advances -to Step 83, where
CP~ 101 outputs a reset signal to clear the counter ]30, then,
CPU 101 advances to Step 84, where CPU 101. discriminates the
presence of an operation command (in operation or s-top) by a
control signal, if the signal of stop is present, CPU 101
reaches Step 13 from Step 84 to repeat S-tep 13 until a con--
dition oE "the machine too]. 400 is in operation" is brought
about. When the condition is "in operation", CPU 101 advances
to Step 85. When the operator moves the table, while ascertain-
ing the positional relati.onship between the work and the tool,
the encoder 200 outputs pulse signals in accordance with the
distance of displ.ac~r~nt,c~nd the counter 130 counts the pulse
signals. When the table reaches a desirable positi.on, -the
table is stopped indisplac~nt. Subsequently, -the counted value
of the counter 130 at this time (i~e~ the di.stance up to the
point i.ntended fo:r) is written in P~M 107 throuyh the con-trol
key of the keyboarcl 153, and CPU 101 advances to the succeeding
Step 88, where one point is-added, and further, advances to
Step 89. In Step 89, when it is not the final point, CPU 101
advances to Step 84, and the abovedescribed steps are repeated
until the final point is reached. Additionally, in the
final point, CPU 101 advances to Step 13, thus completing
the teaching setting flow. Finally, description wi.ll be
given of the con-trol flow with re:Eerence to F`ig. 5.
Firs-tly, when the proyram module 150 is disconnected
from the control moclule 100, S-tep 13 is carried out to perform
the con-trol flow of Step 14 as aforesaid. In the first place,
in Step 32, the machine tool 400 is jud~ed whether it is in
operati.on or at stop, when it is at stop, CPU 101 advances
to 42, where the timer 122 is stopped, then returns to Step
13 to repeat the same until the condition of "-the machine tool
400 is in operation" is brought about. When the machine -tool
is in operation, the timer ]22 for judging whether the encoder
200 is normally operated or not is started to detect the
presence of an abnormality (for example, when even one pulse
is not inpu-tted for one second, the encoder 200 is out of
order), and, when an abnormality is presen-t, the error indicator
121 is operated, CPU 101 advances to Step 13 -to repeat the
same until the normality i5 present, not shown. When the
no~mality is present, CPU 101 advances to Step 34, where the
direction discriminating circuit 124 judges whether the encoder
200 is rotated in the normal direction or in -the reverse
direction, and, the rotation is in the normal direction, CPU
101 advances to Step 35, where a distance output xi from the
counter 130 is written in, advances to Step 36, where a
distance Xi of the desirable point is compared with the afore-
said distance output xi, when the distance Xi and the distance
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output xi become equal in value to each other, CPU 101 advances
-to Step 37, where -the output relay ]23 is operated and one
point is added to the current point Pi (i.e., Pi + 1) to
obtain the succeeding point to be perEormed, then, CPU 101
advances to Step 41, where the distance Xi of -the point Pi -~ 1
is set, and then advances to Step 13. In Step 3~, when Xi is
larger in value than xi, CPU 101 advances -to Step 13 to repeat
the same until x:i and Xi become equal. in value -to each other.
When the encoder 200 is rota-ted in the reverse direction, CPU
101 advances from St.ep 34 to Step 38, where the distance
output xi from the counter 130 is written in, then CPU 101
advances to Step 39, where xi and Xi are equal in va:lue to
each other, CPU 1.01 advances to Step 40, where the output
relay 123 is opera-ted and one point is subtracted from the
current point Pi (i.e., Pi - 1) to obtain the succeeding point
to be performed, then, CPU 101 advances to Step 41, where the
distance Xi of the point Pi - 1 is set, and further, advances
to S-tep 13. In Step 39, when Xi is smaller in value than xi,
CP~ 101 advances from Step 39 to Step 13 to repeat -the latter
until xi and Xi become equal in value to each other~
Description has hereinabove been given of an example
of using a computer. It should be understood, however, there
is no intention to limit the invention to the specific
embodiment disclosed, but on the contra-ry~ the inven-tion is
to cover all modifications falling within the sprit and scope
o:E the invention, for example, the invention can be worked
by use of a coun-ter and a compara-tor, which t~7ill hereunder be
explained wi-th reference to Fig. 3.
Major components in this case include an updown counter
131, a register 132 and a compara-tor 133. ~nputted at -the
input side of the updown counter 131 are reset signals 137,
normal. rotation pulse signals 134 and reverse rotation pulse
signals 1.35 from the encoder 200 through the direction discri-
mina-tlng circuit. 12~, while connected to the output side of
the updown coun-ter 131 are one oE i.nput terminals of the
comparator 133 and a memory, not shown. ~;urthermore, input-ted
i.nto the inpu-t side of the register 132 are a reset signal 137
similar to that in the case of the updown counter 131 and
pulse siynal da-ta Xi determined in accordance with a desirable
point, and the output side of the register 132 is connected
to the other of the input terminals of -the comparator ]33.
The comparator 133 compares the output xi from the updown
counter 131 with the output Xi from the reglster 132/ and,
when the both outpu-t eclual in value to each other, outputs an
output signal.
Description will now be given of action of an ernbodiment
shown in Fig. 3. Firstly, in the teaching mode, when the
table is positioned at the original point, the reset signal
137 is inputted to the updown counter 131 to set the output
to zero, and when the table is at a point other than the
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original point, -the reset signal 137 is no-t inputted and the
table i.s movecl to a desirable point by a desirable method,
the normal rotati.on pulses 134 or the reverse rotation pulses
135 are input-ted to the updown counter 131. Then, -the updown
counter 131 counts the pulse signals from the encoder 200
outpu-tted in accordance ~i-th the c~isplac~n~nt distance and outputs
the same as the output xi to a mernory, not shown. This memory
stores therein this outpu-t xi, and can automat.ically stop
the table of the machine tool 400 at a desirab]e point basecl
on this s-tored data in the control ef~ected thereupon.
Namely, the data stored in the memory as the desirable point
is inputted to -the regi.ster 132 as the data Xi r whereby the
table starts moving to the preset point. During this displacement
of the table, the pulse signals from -the encocler 200 are
upGounted or downcounted by the updown counter 131 in accordance
with the normal or reverse rotation of the encoder 200, and,
when the resultant output xi becomes equal to the data Xi
preset by the regi.ster 132, the comparator l33 ou-tpu-ts an
output signal, whereby this output signal is inputted to the
control panel 300, so that the table can be automatically
s-topped at the preset point. ~ -
From the foregoing description, it should he apparent
to those skilled in the art that the abovedescribed emdodiment
is but one of many possible specific embodimen-t which can
represent the applications of the principles of the present
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invention. Numerous and varied o-ther arrangements can be
readily devised by those skilled in the art without depar-tin~3
:Erom -the spirit and scope of the invention.
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