JPS5888242A - Control method for vibro-isolating table - Google Patents

Abstract

PURPOSE:To secure an optimum level adjustment irrespective of the weight load imposed on a table, by setting up a pulse width available for obtaining the unit ascending distance and unit descending distance of a table supported by an air spring device, while controlling table operation by means of the said pulse width. CONSTITUTION:An air spring device 22 supporting a table 31 is made up so as to cause a sensor 34 to transmit a signal to a controller 35 whereby a suction valve 37 and an exhaust valve 36 are actuated to operate level adjustment. In a state of using the table 31, adding test pulses to the suction valve 37 and the exhaust valve 36, resultantly the ascending or descending distance of the table 31 is measured and, from the data obtained from this measurement, the range of valve operating time commensurate to a unit driving distance is computed, storing it into the RAM of a controller 35. Based on this, an ascending pulse or descending pulse is generated so that if constant setting operation is properly carried out in time of using the table 31, adequate control is thus made possible irrespective of the weight load imposed on the table.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention supports a table on which a shin structure is placed by an air pump iron source, and maintains the arbor at the i-sheng position by letting air enter and exit the air spring device. Make it one way.

Even the slightest vibration or displacement occurs during use of equipment such as 9-character markings, precision-determined flags, IC line-wrapping covers, and child-value caps, which can interfere with the work and should be avoided. In order to protect the machine from the effects of vibration, which may cause the product to become defective, it is best to place the damper 1 on a vibration isolation table 2 as shown in Figure 1. It is being said.

Among these vibration isolators, one of the ones on which the vibration isolators are placed is a table 3 with an air spring device that supports a table 3 with a height of 2 km.

In this ↓ Una Eidori Kaya, air is moved in and out of the air spring device that decorates the table. -m of the valve is performed according to the amount of positional deviation. As a result, the air spring device moves up and down, and the table returns to the first base position.
It is located in Specification No. 3.

Such a conventional vibration isolation table requires a complicated mechanism to prevent vibrations from the floor from being transmitted to a plunger that contacts the bottom of the table and uses the amount of positional displacement of the table. However, depending on the nature of the vibration, even if such measures were taken, the Wi motion would still be transmitted to the table through the plunger, resulting in a drawback.

In addition, when the amount of positional deviation of the table from the reference position is large, the plunger moves a large amount and a large amount of air enters the valve, quickly correcting the table level. Naru K has a small axillary valve opening.
IIIL#l By the time the table returned to its standard position, there was one point where the monk's yellow time threshold had been reached.

The present invention has been made in view of the above points and achieves the following objects.

An object of the present invention is to provide a vibration isolation table control method that detects the position of the table in a non-contact state and appropriately drives the air spring device.

A second object of the present invention is to provide a method for controlling a vibration isolating table that provides an optimal V-pel adjustment function to the vibration isolating table in response to fluctuations in the level of the machine on the table. A third object of the present invention is to provide a method for controlling a vibration isolating table that sufficiently increases the accuracy of level adjustment of the vibration isolating table.

A fourth object of the present invention is to provide a method for removing a vibration isolation table that returns the vibration isolation table to the reference position at high speed.

Figure 2 shows a table 21 on which the method of the present invention was applied.
As seen from above, air spring units [22, 23, 24, and 25 are arranged at the four corners of the table 21, respectively, to support the table 21. Also.

A precise 3iIll that defines the positional deviation of this table 21 from the reference position! The dragon Y26.27.28 is placed below the table 210.

The composition is Ruru.

In the figure, the table 31 is supported by air springs [32]. This air spring *32 Fi has a diaphragm 321 located on the underside of the table, an air fi 322 that supports this, and legs 423. and,! 9! The gI411322 is provided with an air intake port 324 for supplying pressurized air thereto, and an exhaust port 325 for venting air therefrom, and an air chamber 322.
The boundary with the upper diaphragm A21 of it 321i
An orifice 321 having a through hole of constant diameter is fixed.

On the other hand, the arm 3 of the air spring 1it32 has begun to rise to you.
A sensor 34 is installed in the third upper gallery with a downward pressure distance from the table 31. This sensor 34 adds the threshold value t'nmK#j between the upper side of the sensor 34 and the lower side of the table 31, and sends this information to the control device 35. The dividing device 35 determines whether the table 31 with this information K11lli should be raised or lowered, and operates the exhaust valve 36 or the intake valve 31. Since the RI combined air 9P36 is connected to the exhaust port 325, when the exhaust valve 36 is opened, the air in the air chamber 322 is exhausted, and the diaphragm 321 moves accordingly.
1 goes down. Also, when the intake valve 31 opens, the compressed f! The pressurized air accumulated in the air intake port 32
4 into the chamber 322 and stretches the diaphragm 321 through the orifice 321, causing the table 31 to rise.

By performing this operation using the four valley air spring devices that support the table, the table can always be maintained at a predetermined level from the floor.

FIG. 4 is a block diagram illustrating a method for verifying four air spring devices as shown in the WIpJz diagram using three sensors. In order to make this figure correspond to FIG. 2, the corresponding sensors and air springs ikw are given the reference numerals 111-.

In the figure, the sensor 21 sends the information person corresponding to the positional overlap of the table to the side control device 41, where it
! A rising pulse A+i or a falling pulse 8- which is necessary for i is generated. According to this, the intake valve 42 is combined air 9P43
operates by 1 mm to adjust the level of the air spring device 24. Regarding the sensor 28, the same result is obtained. On the other hand, Census 6
detects the positional shift weight of the table between the air spring devices 22 and 23, and based on that information, the rising pulse C+h or the falling pulse C- simultaneously moves the two nitrogen springs to levels i & 1 II11. do it like this. this is,
Connect the air chambers of the two devices with pipes, etc.! It is created by installing the intake and exhaust valves of LLI.

Now, let's look at how the above-mentioned sensor detects the positional deviation of the table, and according to the above-mentioned Ik meeting, how does the table return to its level in response to the displacement of the root plate? is explained below.

FIG. 5 is a block diagram showing Senna's M-hoshio.

In the figure, the sensor 51 is an oscillating 1gi complex 511.

Take out the resonant circuit between the coil 512 and the converter 513 to which this oscillation 'l1lL flow is supplied, and the '1 faction that may be connected to this resonant circuit! It is composed of IgL and a Tsuboshin circuit 514 that converts it into direct current. In addition, the output from the sensor 51's adjustment circuit M 514 is transmitted via the No. 91 cable 52.
y /<It is sent to 531.

This sensor 511I'i actually operates as shown below.

The oscillation circuit 118511 is caused to oscillate at about 200 volts around the circumference of the circuit, and the excavated current is supplied to a common I&I circuit connected in parallel with a 250 .mu.h coil 512 and a 0.01 .mu.F capacitor 513. For example, as shown in FIG. 6, a coil 62 is attached close to the under-table 61 (a magnetic plate provided at the bottom of the table). When the table 61 goes up and the table goes down as shown in FIG. 6, the impedance of the coil b2 changes. Therefore, as shown in diagram 11K7, the impedance 2 of the above-mentioned resonant circuit changes according to the change in the inductance L of the coil, ! 71t - It is one of the deceptions of pressure against Kang, which is a big deal. Here, when the distance between the coil 62 and the table 61 is 10.0, the round constant ridge is set so that the inductance L becomes the value at point A in FIG.

The impedance of the resonant circuit increases as the table 61 rises and decreases as it descends.

Therefore, if a constant excavation voltage of tI1g circuit K 200 KJlz is applied, the electric current fL produced by KtIL here
changes to IJ near, and this rectified note becomes a wax corresponding to the level of the table. According to the sensor exemplified above, when the distance between the table and the coil is 1105a, the adjustment is t11. The circuit i [outflow voltage is 2.5V, which is 1
When the level reached 5, the output voltages #io and sv were detected, and the level of the table could be detected well.

Moreover, as shown in FIG. 5, only a DC voltage is applied to the deflection cable 52 extending to the straight line b3 of the 111KIIil vehicle, which provides a non-IIK strong advantage against noise.

The pillars that are covered with ice on the vibration isolating table can be made in various ways depending on the purpose, but the pressure on the thighs of about θ ~ 5V obtained from the sensor using the method described above can be converted into MU/ to withstand it. If you do the hook, the position of the root rat will shift by 20μ, and the t% measurement will increase.

The above sensor output is processed and the valve is opened/closed at tIf.
A jf# resistant device for ll# will be explained with reference to FIG.

FIG. 8 shows a block diagram of the control device. This Mv4 device digitally converts the output voltage signal from the sensor 801 by the A/D converter 8LI2, and sends its polarized sign to the output voltage signal line 1104 of the CPU 11Q3. This path line is a ROM IO3-? in which programs etc. are written. 1tl
lj # ff1tit ms 806 -
? , Ilo bo--) which emits an output of 111111 squares.
8071 meals! has been done. CPLI 1m◎3 Tsumugi,
Sen? 10, and the data corresponding to the level type where the table should originally be located, determine whether the exhaust valve should be opened or the intake valve should be opened. Pulse λ + bad or lower - pulse 7 is output. Drives 1G and 11 are activated by this rising pulse or lower eye pulse.

These drive circuits 810 and 811 operate at a voltage tON of 24V, for example, when the exhaust valve 808 and the intake valve 809 operate.
'to'. And this drive time 1810°811
can be formed by a switch circuit using Kochi's transistors.

The level of the chiful to explain how to raise it by My Jl wax filling and raise it by one level to the level adjustment work area centered on the reference position 91, that is, the reference area 95,
It shows the time variation of the rising pulse that activates the intake pulp.

In Fig. 2, the table is initially at position 92, but when the intake valve is opened for one second as shown in Fig. 1O, -
It rises at the upper end 941 of the speed inertia area S3.

In the low speed region 96 above the cedar, the rising speed is reduced in order to suppress hunting of the table.

For this reason, the opening time of the intake valve once is set to be short, 1 second, and
This operation is performed once every m fixed times E, and the operation is stopped when one level of the table returns to the reference area s5.

As described above, by providing two upward movement areas, the table rises quickly and huntingly to the target reference area. It goes without saying that, as will be described later, it is preferable to provide an area above the reference area 11i1 for the descending speeds of the two aircraft.

Here, we will specifically explain the operation of the intake valve and exhaust valve and the upper and lower positions of the table using Yuri's am.

In actual victory, when the first child of the MA machine on the table is 120 o'clock, g! , the air pressure in the air spring Ii & wax air chamber is 3yu/
- When the intake valve is raised as shown in Fig. 11/< Lu x A + K, the table will rise by 400 m5ec and the table will rise by 400μ, and when the exhaust valve is opened by 51m5ec by the construction pulse, the table will rise in the same way. is 400
μ Seal descended.

In this way, since the +a output X electric current on the table is directly applied to the air spring device, if you try to make the table move the same @O displacement, the operation time of the intake valve and exhaust valve will be reduced. are significantly different. And table 42) 萄
If fLK changes, each regret also changes along with fLK.

It is preferable that the unit rise IITo or unit fall amount of the table, that is, the level JIIK# weight, remain constant.

In addition to the test pulse of the intake valve and exhaust valve while the table is in use, we also measure the accompanying rise or fall of the table. Then, from the data obtained from this K, the operating time of the valve O corresponding to the unit drive is calculated, and the control device M of the eighth control device is determined to be stable.
Is it possible to do the above by storing it in BD memory? #Never.

FIG. 12 shows changes in the level of the table during the work of determining this fixed value.

When a horse is running well on the table within the reference range 121, the table is moved upwards as shown by @ trout H by the rising pulse 122 shown by A0, and the amount of change in level is determined by -j.

0-order KA that calculates the unit rise amount specified by the agency from the time width of this pulse and the amount of level change.
- Add lower IQ pulse 123 as tbj,
Calculate the flow of the lower-pulse to obtain the unit lower t11# child. These m holds are stored in the RAM 806 shown in Figure 8, and each time a table rise or fall command is output from the CPU 803, the rise pulse corresponding to the sheep position fl J lid is output from the J boat. A falling pulse is emitted.

In other words, if you change such a redundant fixed cropping prefecture depending on the usage condition of the table, you can set an appropriate constant according to the usage condition of the table. Can be set.

Now, if you do the above, you can move the table up and down by operating the intake valve and exhaust valve with the rising pulse and the falling pulse. This will not work unless you apply a pulse of c? Second, the present invention': The square used in 4i fathom should not be produced unless 1) a - pulse of 50 m5ec or more is applied at C24V. However, 59Kng
If the cell is opened by 50mat by the pulse of
When descending, a level change of 4QQgn occurs, and if the reference executive circle goes out by 200 μm @ degree, it becomes impossible to stably hold the table within this range.

Therefore, in the present invention #4, as shown in Figure 13, the above-mentioned problem is solved by emitting a combination of rising pulses and falling pulses.

-, an ascending pulse A0 is issued for 2QQmsec to open the intake valve for 2QQmsec, and after 500m, a descending pulse is issued for 50m5ec to operate the exhaust valve '15Qm&. It takes about IQ m sec from when the control device starts generating such a pulse until the valve starts operating, and since this response time difference is not large in the diagram, only each pulse is displayed and the valve starts operating. The light indication for opening/closing operation is omitted.

However, when either the intake valve or the exhaust valve is activated, the g! It takes about 3 seconds for the air spring W and the air in the vertical air chamber to come into contact and actually move the table up and down, so the table does not actually move up or down after the intake valve and/or exhaust valve starts operating. Before starting, if the intake valve and/or the exhaust valve are operated simultaneously to a predetermined opening, the result is the same as if the combined air inflow or aaS of these operations had been performed. arise. In other words, this sardine rice @-13 in Figure 13
1, the table simply rises, and it is possible to obtain a small amount of rise of %/h1 [%/h1] which cannot be obtained by operating only one of the intake valves and #i exhaust valves. If the above-mentioned unit 1AIIb is thereby obtained, extremely precise level adjustment becomes possible.

In adopting the control method shown in FIG. 13, the smoothness of the ascending pulse and descending pulse to be emitted in combination is determined in advance, and the six tasks of creating an excessive combination are made public expense. This method is illustrated by 紽14 diagram i15! I will clarify.

First, when the vibration isolating table is used, when the table reaches the predetermined range, a rising pulse of 1200 m is emitted as shown in the figure. For example, a falling pulse with a delay of 1-5 QffllE is generated with a delay of 300 m. Then, the level change on the table that occurs after about 3 seconds is measured. Without changing the ring of the ascending pulse for a long time, the lower pulse's tail is 6I 10,000, 7 guuec.
Expand the table and plot the level change of the table, the width of the falling pulse, and the °C relationship as shown in Figure 15. Theoretically, using this gIai&-''' tag valve and exhaust valve as the
By combining the valves as shown in Figure 3, it is possible to correct the displacement of the table in a very small manner without being affected by the response performance of the valve.

Now, according to the Senna, which was prototyped by the present inventors and shown in Figure 6, the rising edge of table level mineralization adjustment is about 20 am, and the rising pulse of 200 m5a: and 55 m. By combining the descending pulses of dew, a unit rise of 30 μm was obtained, and by combining the rising pulse of 200 m5ec with the descending pulse of 110 mW-, a unit rise of 30 μm was obtained, and the inner surface of the table was quickly filled. It was designed for use in low evacuation areas. This series of operations is shown in Figure 8, section 1i41! Using the pulse width determination program stored in iIK's 90M805, for example, the descending balloon X- is changed within a predetermined range as a parameter for a predetermined - rising pulse, and the level change in the table at that time is Compared to the unit drive type, which is set up and stored in the ROM 805, an excessive pulse width is selected, and this koshiki is stored in the RAM.
This is done by letting $06 get used to 1jI2.

Figure 16 shows the 1111II41i that handles such processing.
This is a lobogram border chart of Ikden.

This method #i First, place 4! on the vibration isolation table. When the power to the l11111 station is turned on to start using the r-loading machine, the vibration isolation table is used and the above-mentioned process is carried out.

Note that this figure will be explained with reference to the block tire gram in FIG. 8.

In the figure, when the electric wire of the control device is inserted, k4A) MS
The program loaded with les K starts, and from JM 1105, it corresponds to the upper level - JII weight and the lower level - weight, which was applied to the smooth and moist layer from JM 1105. The amount data of the rising pulse and falling pulse are transferred to AMK.Next, the CPU reads the data of the sensor 801 and reads the data of the table !111.
Calculate the position deviation by comparing with the position, and since the table on the fufu air spring acupuncture needle is set to the lowest position when not in use, it is determined whether the position is in the high speed range or in the low speed range 11L. Decide if it will work. Then, it is determined that this is in the high speed range, the intake valve is turned on, and the program returns to the LOOP point.

After a while, data Bk coming from another sensor is subjected to the same processing as above, and after data CO processing is performed, data A is again interpolated.

At this time, based on the results of the previous process, when the table enters the slump region, turn on the intake valve. OK'? and then emit a rising pulse '4I:1') to obtain a unit rising amount,
This pulse width is determined using * quasi data. Below t
I! 3@, the cycle of detecting the positional deviation violet and generating the rising pulse as described above is repeated, and the table is brought up to the base level.

When you reach this veranda, add whether or not you have entered the process of setting the unit increase amount and single drop paralysis amount, and enter jJIK at this point.

Below the 8NT point of the program in Figure 16, only when the table crosses the reference area, as shown in Figure 12, a combination of rising pulse + and descending Hals pulse - is generated, and the unit of the table generated by this K is generated. Determine whether the drive type is stop.

For example, if the rising pulse is 200 Lntyec, the lower Ill
When the table is lowered by 35 μm when the pulse is 110 m5ec, if the unit 'HA @ II is set to 30 μm, the lower I curve is decreased by 1 ms& and the displacement voltage of the table is determined to #l. In this way, the unit drive mt
Once the data of the - combination of the rising pulse and the falling pulse for suppressing the pulse is determined, the standard data convoluted into the lume M at the beginning is replaced. And the unit JI11!1
W Sumire decision whirlpool! This prevents the program from entering the 19kT point.

After this, each sensor also checks whether the table has deviated from the reference area, and then a rising pulse or a downward pulse is emitted only for the necessary ridges, and the table is refilled for 14 minutes. I'll bring you home. This type of processing using a micro combinator is extremely fast compared to the air/(metallic comb 2) process, so even if the sensor has more ridges, it appears that ifi is the air spring iit. will move upward or downward almost simultaneously.

FIG. 17 shows tables at levels 114 and 175 of slump regions 172 and 113 that are adjacent to the upper and lower sides of the reference region 171, respectively. A quasi-region 1' by unit drive of l
71 is shown. Further, FIG. 18 shows, for example, a slump region 182 below the reference region 1810, and a further two regions.
divided into two velocity regions 183 and 184, each with level 1
The case where IA11i1 layer is changed is shown.

In FIG. 18, since the unit rising chamber is 2 m long, the table is lowered to the slump region of 1 m $ 4 of the torque I, returns to the second low speed region 183 at a comparatively high speed, and then returns to the second low speed region 183. The low speed 1!1 of JaiL183 can be sufficiently sandwiched to speed up the response of the table as a whole.

Figure 19 shows a modification of the sensor used in the method of the invention, which optically tracks the position of the table.

In this example, the light is emitted by the light emitting element driving circuit 151.
7 is fired by actuating the shutters 185 and 196, and the beam reflected by the beam attached to the underside of the table 190 is first received by the two-dimensional image sensor 191. From now on, the slope of the table 1sO is 1! You can know how much the table is tilted from the horizontal position by using the original image of two people.
III if 1911 K feed and return table 190 to horizontal position. Lizard on the bottom of the horizontal table 11
If the image sensor 192 is chipped at a predetermined angle from a predetermined position at a predetermined angle by the originator 196, the level of the chifur can be output from the deviation of the original position.

As described above, according to the method of the present invention, the position of the table can be determined in a single table without contact with the table, and the table can be returned to the ilh early position line position. Also, the time spent on the maid can be much shorter than in the traditional wax method.

Furthermore, according to the various problems described in this book, it is possible to computer-process the leveling of the vibration isolation table using a comparatively simple 70 grams.

It should be noted that the present invention is not limited to the above-described embodiments, and can be modified as shown, for example.

1) How to use 7-t to change electrostatic weight.

It can be directly converted into a non-contact method to detect the distance between the insect's proboscis.

2) The air spring installation can be modified to a hanging type.

3) The system #tack is overflowing with its program history, and when it falls down, the operator gives instructions and performs the process of setting the initiative, weight, etc. at any time. Show! ! You can add a position.

4) Also, the units of movement + spirits at the time of rising and during the time of lowering can be made different as necessary.

[Brief explanation of the drawing]

Figure m1 is a perspective view of a group of ants that favor the cultivation of the method of the present invention, Figure 2 is a diagram showing the implementation of all the troubles of the present invention - the upper part of the tower, and Figure 3 is a diagram of the air springs. The zonal diagram of Figure 4 is air bar +
*The block diagram of Nao's blade, Figure 1ii145 is the block diagram of Senna, Figure 7 is the sensor construction 111#
Figure 8 is a block diagram of the pumping device, Figure 9 shows the table's level combination, Figure 1O shows the corresponding rising pulse, and Figure 11 shows the same level combination. Figure 12 shows the table level changes due to the rising pulse and falling pulse. Figure 13 shows the rising pulse and the falling pulse. Figure 14.15 shows the table level changes that occur. Figure 14.15 is an explanatory diagram of the process that determines the ratio of rising pulses and falling pulses. Figure 16 is a flowchart on the level side of the circuit. Figure 17
, 18- show the level change of the table by the unit wh movement, 79 steps, and FIG. 19 shows a modification of Senna. 21.31...Table 22.23.24.25.32...Air spring restraint 26
．． 2T, 28.34.51... Senna 324...
... Intake port 325 ...... Combined air port 31.42.44.46 ... Air valve 36.4 in 111
3.45.41 ...exhaust valve 35.41,! 13
...Control W & Kasumi 0 ...Reference position Tsuru 6.121, 178.1@1 ...Kabu semi-region person +
...Ascending pulse A-...Descending pulse Fig. 4 Fig. 6 Fig. 7 Fig. t This interns Fig. 7 Fig. 13 Female Fig. 1/7 Fig. 18 Fig. 1q

Claims (1)

[Claims] 1. A table to be level-controlled, an air spring device that supports this table, a sensor that detects the amount of positional deviation of the table from a reference position, and a pressurized air spring device. In a vibration isolation table having an intake valve connected to an intake port for feeding air and an exhaust valve connected to an exhaust port of the air spring device, the intake valve and/or the exhaust valve are used to return the table to the reference position. In the method of adjusting the level of the table by calculating the time width for operating the valve from the positional deviation amount and operating the intake valve and/or the exhaust valve, The widths of the rising pulse and the falling pulse are set in advance, and the rising pulse is intermittently emitted to operate the intake valve, or the falling pulse is intermittently emitted to operate the exhaust valve to move the table to the nest position. A method for controlling a vibration isolation table, characterized in that the table is displaced for each amount of rise or fall of the nest position. 2 Depending on the amount of positional deviation from the reference position of the table.
The above rise or fall speed areas were determined, and the amount of rise and/or unit fall of the nest height was made different for each area, and in the area close to the reference position, the amount of rise and/or unit fall of the nest position was decreased by /11. A method for controlling a vibration isolation table according to claim 1, characterized in that: Below margin 1 - -
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