JPH01303301A - fluid equipment - Google Patents

Abstract

(57) [Summary] This bulletin contains application data before electronic filing, so abstract data is not recorded.

Description

DETAILED DESCRIPTION OF THE INVENTION <Industrial Application Field> The present invention relates to a fluid device that controls the amount of operation of a piston rod of a fluid pressure cylinder.

<Prior Art> Conventionally, as a fluid device of this type, one is known in which the reciprocating motion of a piston rod of a pneumatic cylinder is converted into rotation of a ball screw shaft to position the piston rod.

In this fluid device, a piston with a hollow piston rod a is slidably fitted into a tube of the main body, a ball nut is fixed coaxially with the piston, and a ball screw shaft is screwed into the ball nut. is extended into the piston rod and attached to the main body so as to be rotatable and immovable in the axial direction to form a pneumatic cylinder, and between the main body of the pneumatic cylinder and the ball screw shaft there is a shear electromagnetic device that brakes the rotation of the ball screw shaft. In addition to providing a brake, a rotary encoder is provided at the end of the ball screw shaft to generate a pulse signal according to the rotation angle of the ball screw shaft, and a control device is provided that outputs the pulse signal representing the current position of the cylinder rod and a pre-given signal representing the target position. When both signals match, a braking signal is output to the electromagnetic brake, and the supply of drive air is stopped to stop the piston rod at the target position. When the thrust force accompanying the reciprocating movement of the piston rod is converted into rotation of the ball screw shaft via the ball nut, this fluid device is significantly reduced by a reverse boost effect, so it directly brakes the piston rod. This has the advantage that there is less slippage, more reliable braking action, and less energy required for braking, and since an electromagnetic brake is used, the holding force is greater.

<Problems to be Solved by the Invention> However, although the conventional fluid device has the above advantages, it still has the following problems. In other words, in the conventional fluid device described above, the electromagnetic brake is continuously applied to the ball screw shaft for a period of time corresponding to the speed of the piston rod to perform braking. This has the disadvantage that the braking force applied to the ball screw shaft varies, and the piston rod stop positioning accuracy or speed control accuracy gradually decreases.

In addition, electromagnetic brakes generate more vibration and shock during braking than other brakes, and have a large depletion rate, so the continuous braking mentioned above shortens the life of the electromagnetic brake and the life of the cylinder body, and also reduces the life of the piston rod. The disadvantage is that vibrations are transmitted to the load side connected to the

Therefore, an object of the present invention is to provide an auxiliary differential braking means in addition to the electromagnetic brake, and operate these in appropriate combination to avoid continuous braking or braking with a large impact due to the electromagnetic brake, thereby improving the electromagnetic brake and fluid pressure. It is an object of the present invention to provide a fluid device that can extend the life of a cylinder and can precisely stop, position, or control the speed of a piston rod.

In order to achieve the second object, the fluid device of the present invention includes a piston having a hollow piston rod that is slidably fitted into the chicob of the main body, and a piston that is coaxial with the piston. An output shaft consisting of a ball screw shaft screwed into the ball nut is fixed to the main body so as to be rotatable but not movable in the axial direction by extending inside the piston rod. a fluid pressure cylinder, an electromagnetic brake installed between the body of the fluid pressure cylinder and the output shaft to brake the rotation of the output shaft, and a rotary encoder that detects the amount of rotation of the output shaft of the fluid pressure cylinder as an electrical signal. and a main electromagnetic switching valve that switches and connects a pressure source to a first port of the fluid pressure cylinder to cause the piston to reciprocate, and a flow path connected to the first port of the fluid pressure cylinder. a first braking line connected to the fluid pressure cylinder; a second braking line connected to the flow path connected to the first port of the fluid pressure cylinder;
A sub-electromagnetic switching valve that connects a pressure gap to either the first braking line or the second braking line, and a drive signal that controls the main electromagnetic switching valve, as well as a detection signal from the rotary encoder and Depending on the deviation from the signal representing the given target value and the operating range, the main 71!
A primary braking signal that switches the sub-electromagnetic switching valve so as to apply back pressure to the piston driven by fluid pressure passing through the magnetic switching valve and a secondary braking signal that operates the electromagnetic brake are output, and the piston is driven. 1] Zuro is characterized by being equipped with a control device that allows it to stop smoothly at the target position.

When the target value of the piston rod is set in the control device, the 4' filter main electromagnetic switching valve, which is operated by the drive signal output from the control device, connects the pressure source to the first port of the fluid pressure cylinder. , the piston moves forward. The forward motion of the piston is converted into rotation of the ball screw shaft via a ball nut fixed to it, and the amount of rotation of the ball screw shaft that corresponds to the amount of displacement of the piston is detected by a rotary encoder and input to the above control device as an electrical signal. be done. The control device outputs a primary braking signal to switch the sub-electromagnetic switching valve according to the individual difference between the detection signal from the rotary encoder and the 4゛ signal representing the target value and the operating range. Fluid pressure acts on the first port side of the fluid pressure cylinder from the pressure horn source via the second braking line, and applies back pressure to the reciprocating piston to brake it.

In addition, the control device may be configured to operate depending on the deviation and the operating range, especially in the vicinity of the target position. I! A secondary braking signal that activates the magnetic bushing brake is output, thereby braking the rotation of the ball screw shaft, and the piston connected to this via a ball nut smoothly stops at the target position.

The control device can output the primary braking signal and the secondary braking signal, for example, by outputting the former in the early stage of braking, both in the middle of braking, and the latter in the latter half of braking. The latter can be output continuously and the latter intermittently, respectively. These braking methods and control for each operating section reduce vibration and shock during braking by the electromagnetic brake, and improve the accuracy of piston rod stop 1 positioning. This can extend the life of the electromagnetic brake. The operation of the piston rod in the backward movement is similar to that in the forward movement described above.

<Example> Hereinafter, the present invention will be explained in detail with reference to illustrated embodiments.

FIG. 1 is a schematic diagram showing an embodiment of the fluid device of the present invention, in which a piston 3 having a hollow piston rod 4 is slidably fitted into a tube 2a of a main body 2 (1: A ball nut 5 is fixed coaxially with this piston 3, and a ball screw shaft 6 is screwed into this ball nut 5.
, an air cylinder extending into the piston 3 and rotatably attached to the main body 2 so as to be immovable in the axial direction; 7 is the ball screw protruding from one end of the main body 2 of the air cylinder 1; An electromagnetic brake consists of an armature 7a fixed to the shaft 6 and an electromagnet 7b fixed to the main body 2 so as to face this, and 8 is a rotary encoder provided at one end 6a of the ball screw shaft to detect the amount of rotation of the ball screw shaft 6. be.

Further, +3 connects the main line 10 connected to the first air source 9 to the first port l) of the air cylinder 1.

A spring center type 3-position, 5-port main electromagnetic switching valve is connected to the first line 11 connected to the first line 11 and the second line 12 connected to the first port P, and 15 is the air cylinder!
The first port P of the tube 2a.

The first braking pressure port PI” provided at the side end is connected to the second air source I4.
A first brake line 16 connects to the second brake pressure port Pt' provided at the end of the tube 2a of the air cylinder 1 on the first port Pt side to the second air source 14;17. 18 is the first braking line I5 and the second braking line I5.
Spring-offset normally closed 2-position, 2-port sub-electromagnetic switching valves 19 are respectively installed in the brake lines 16 and output drive signals Ss and Ss' for controlling the main electromagnetic switching valve 13, and output signals from the rotary encoder 8. According to the deviation between the detection signal S1 of the controller 19 and the target value set by the target position input device (not shown in the figure) equipped in the control device 19, and the operating range of the piston rod 4, the main 1i magnetic switching valve 13 is ■Next braking signal S to switch the sub-electromagnetic switching valves 17 and 18 to apply back pressure to the air-driven piston 3
, S, ° and a secondary braking signal S for operating the electromagnetic brake 7 to smoothly stop the piston rod 4 at a target position.

Main line above! 0 on the first air source 9 side and the first air source 9 side. The second air source where the second brake line 15.16 joins! On the 4 side, there is a pneumatic Al7J adjustment unit 21 in which a pneumatic filter 22 and a lubricator 24 are arranged before and after the pressure reducing valve 23, respectively.
intervene respectively. In addition, a speed control valve 25 consisting of a check valve R-26 and a variable throttle valve 27 connected in parallel is installed in the "-article 1 line 1■" and the second line 12 connected to the air cylinder 1, respectively, using a meter-out method. Furthermore, on the 1711m switching valve 13 side of the first line 11, a check valve 29 is provided in parallel to prevent the flow toward the pressure reducing valve 28 and the first port P of the air cylinder I. The main electromagnetic switching valve 13 has a supply port S and two cylinder ports C, , C.
t and two exhaust ports El and Et, the supply port S communicates with both cylinder ports C,, C2 at the neutral position, and the first port P1 of the air cylinder L at the right symbol position, and the left symbol Air is supplied to the first port I)t of the air cylinder 1 at the respective positions. Note that a muffler 30, 30 is provided at the exhaust ports E, , E,. Further, when the main electromagnetic switching valve 13 receives the drive signal S3 from the control device 19 and is in the right symbol position, the sub ffl magnetic switching valve 18 receives the primary braking signal S4 from the control device 19 and moves to the right. It switches to the symbol position and supplies back pressure air to the second braking pressure port P*'. Similarly, when the main electromagnetic switching valve 13 receives the drive signal 83' and is in the left symbol position, the secondary 7Ti magnetic switching valve 167 is in the left symbol position. Upon receiving the next braking signal 84'', switch to the right symbol position and supply back pressure air to the first braking pressure port P,''.

The control device 19 has an interface 31 that exchanges the cylinder operating state of the control device 19 and a human output signal S for remote cylinder operation with the external device 20 with an external device 20, and an interface 31 that controls this device. signal S1 from interface 3I and rotary encoder 8
Air cylinder based on! The CPU 32 performs calculations necessary for the control of the CPU 32, receives one word from the CPLI 32, and generates a secondary braking signal S to the electromagnetic brake 7. In response to the signal, a drive signal S to the main 1ri magnetic switching valve 13 is sent.
An excitation signal generator 34 that generates primary braking signals S, , S4° to S3' and the sub-electromagnetic switching valves 17, 18, and a driver 35 that amplifies and outputs the signals from these signal generators 33, 34. Consisting of

The above CP LJ 32 is a positioning start signal (start manually) provided in the control device 19 or from an external device 20.
is given, as shown in FIG. 2(a), the 11 mark position setter (keyboard
(not shown)), from the deceleration start position x 1 to the target position
n operation sections 11, . . . , 11 . ...
, In, the target speed vl +... of 6 sections fjj
, vi, . . . vn, the following intermittent operation means and continuous operation means are provided. That is, the intermittent operation means is configured to set the target speed vi for each section and 1 notarien=
1-Compare the measured piston speed V in that section obtained from the detection signal S from the da 8, and if V≧vi, the sub 711
Magnetic switching block F! 7.18, the primary braking signal S4°84'? [The secondary braking signal S continues to be outputted to the magnetic brake 7 intermittently.] Therefore, in the example of FIG. 2(a), if the actually measured piston speed V matches the ideal deceleration curve C by 4 degrees, then the portion of the thick line in each section, that is, the entire area, is sub-normal? ! ! Braking by the magnetic switching valves 17, 18 and the electromagnetic brake 7 is intermittently applied to the piston rod 4. In particular, the secondary braking signal S, which is output intermittently, switches at high speed,
On average, this is equivalent to a case where the braking force changes continuously.

Further, as shown in FIG. 2(c), the continuous operating means is configured to operate within n operating sections of the ideal 6λ speed curve C as described above.
If the measured piston speed V exceeds the section speed V at least in the section on the side of the deceleration start position
s, + continues to be output, and thereafter a braking state occurs throughout the area (1) regardless of the actually measured piston speed V. Therefore,
In the example of FIG. 2(c), if the measured piston speed V matches the ideal deceleration curve C, then the first section! Braking by the sub-electromagnetic switching valve 17 and 18 is continuously applied to the piston rod 4 in the entire area indicated by the thick line in 1, and in the subsequent sections I, ~I, 7
Intermittent braking is applied only by the IX magnetic brake 7.

The intermittent operation means and the continuous operation means can operate only the RIIF person or both of them, depending on the setting device (switch, etc.) installed in the control device 19 or the braking mode signal from the external device 20, and only the 011 person can be operated. If you work, -
According to the control mode signal described in , the i-th braking signal S, , S, °
It is possible to specify any combination of the operation period in which the intermittent output of the operation period and the secondary braking signal S, and the intermittent output staggered operation period can be specified, and when both are to be operated, the primary braking signal S4. An operation section in which S4' is continuously output and an operation section in which the secondary braking signal S is intermittently output can be specified in combination with flft. In other words, in Fig. 2 (L,), for example, the primary braking is in the high speed range, and the secondary braking is in the medium/low speed range and when stopping.
Next braking, in the high/medium speed range! Next braking, 2 in medium/low speed range and stopping
The control mode signal can specify primary and secondary braking for six speed ranges, such as primary braking in all speed ranges and secondary braking at a stop. The intermittent or continuous operation means for the primary braking force and the secondary braking force can be designated by the braking mode signal, such as using an intermittent operation means for the braking force or an intermittent operation means for the primary braking force and the secondary braking force.

The operation of the fluid system having the above configuration will be described below with reference to the flowcharts of FIGS. 3 to 5 showing the flow of processing by the control device 19.

Now, a positioning start input (start input) is manually input to the control device 19 from the external device 20 or a switch installed in the control device, and the target position (already set) is to move the piston rod 4 of the air cylinder 1 to the left in FIG. If you want to make it stand out,
The CI'U 32 determines to start positioning control in step Sl, and proceeds to step S2. Then, in step S2,
Excitation signal generator 34. When the drive signal Ss' is output to the main electromagnetic switching valve 13 via the driver 35, the main electromagnetic switching valve 1
3 switches to the right symbol position and the 1st air source 9
through the first line 11 to the first port P of the air cylinder 1
1, and the first port of the air cylinder l is released to the atmosphere via the second line 12. Further, in step S3, the brake signal generating section 33. A secondary braking signal S output to the electromagnetic brake 7 via the driver 35,
When stopped, the attracted armature 7a separates from the electromagnet 7b, and the ball screw shaft 6 becomes rotatable. Therefore, the piston 3 moves forward to the left in FIG. 1 by the air supplied from the first port P1, and the forward movement of the piston 3 is converted into rotation of the ball screw shaft 6 via the ball nut 5 fixed thereto. The rotation fit of the ball screw shaft 6 is detected by the [l-cli encoder 8, and is inputted to CI''032 of the control device 19 as a pulse signal S1 corresponding to the piston position.

CI) 032 uses the above positioning start input (start input) to determine the deceleration start position X according to the ideal speed curve 1aC (see Figure 2), divides the curve C into n operation sections, and Based on the braking mode signal and the control mode signal, it is determined whether the braking in the δ operation section is in an intermittent or continuous mode, and whether the mode is the first braking, the second braking, or both. In this flowchart, for convenience, the following explanation will be given assuming that the control and braking modes shown in FIG. 2(c) are set. In step S4, the CPU 32 determines that the piston position indicated by the pulse signal Sl from the rotary encoder 8 is the deceleration start position x1.
It is determined whether or not this has been reached, and if it is determined that it has been reached, the process proceeds to the first braking subroutine of step S5, which is the control mode of the first section.

This first braking subroutine is as shown in FIG. That is, in step S31, the CPU 32 determines whether or not the piston position h indicated by the pulse signal S1 is less than the primary braking section. If not, the CPU 32 releases the primary braking force in step S34, and returns. If it is the primary braking section, it is determined in step S32 what the braking mode is, and if it is continuous braking, the primary braking force is applied in step S3G and the process returns. In the case of intermittent operation, the measured piston speed V represented by the pulse signal S1 is determined in step 833 as the section speed v.
, that is, whether or not continuous braking is necessary. If it is not, the process proceeds to step S35, and the primary braking signal S is sent to the sub-electromagnetic switching valve 18.

is continuously output, and the sub-electromagnetic switching valve 18 is switched to the right symbol position to connect the second air source 14 to the second braking pressure port P,° of the air cylinder l via the second braking line i6. Then, the back pressure from the second braking pressure ball l'I't' acts on the piston 3 moving leftward in the figure toward the target position X, the piston 3 is decelerated, and the process returns to the main routine. Return. If the measured piston speed V is equal to or less than the section speed V, in step S34, the primary braking signal S4 is stopped, continuous braking by the sub-electromagnetic switching block F18 is released, and the process returns to the main routine. Since the primary braking not shown in FIG. 4 is performed in a subroutine in which the cylinder is moving, intermittent braking is performed so as to correspond to the ideal deceleration curve C (in the case of intermittent braking) as determined in step S33.

In this way, the process proceeds to step S of the main routine in FIG.
Move on to 6. Step S6 is the second section of FIG. 2(c)!
, the subsequent control mode is Brugin, which performs secondary braking (
5th illustration). In step S40, the pulse signal S
It is determined whether the piston position indicated by l is in the secondary braking area, and if not, the secondary braking force is released in step 843 and the process returns. If it is a secondary braking section, it is determined in step S41 what the braking mode is, and if it is continuous operation, the secondary braking force is braked in step S45, and the process returns.

In the case of intermittent operation, it is determined in step S42 whether the measured piston speed vh<the target speed vi of each section 1i (i≧2) or less.
Proceed to step 44 and perform intermittent braking, and if it is not above (y<
vi) Proceed to step S43, release the intermittent braking, and return.

In step S9, it is determined whether or not it is the final section based on the piston position indicated by the pulse signal S, and if not, the process returns to step S4 to repeat the braking loop, while if YES, the process proceeds to step SIO and the target position X is reached. Determine whether or not. If it is judged as 1°r, a secondary braking signal S5 is output to the electromagnetic brake gear, and the electromagnetic brake 7 brakes the rotation of the ball screw shaft 6 to stop the forward movement of the piston rod 4. Next, in step SI2, it is determined whether or not it has stopped at the target position S,,S,.

The piston 3 is positioned with the first air and the air pressure of 1 applied to both sides of the piston 3 via the switching valve 13, which becomes the neutral position.

Finally, in step S14, a positioning completion signal is output to the external device 20, and in step SI5, the next target position is set by the CPU 32 according to the positioning control sequence, and then the process returns to step S1. It goes without saying that in the case of backward movement in which the piston rod 4 is reversely retracted to the right in FIG. 1, the same control as in the above-mentioned forward movement is carried out.

In the above embodiment, the first.
The first brake pressure port P+'*Pt' is connected to the second braking pressure port P+'*Pt'. Second
Direct air source via brake line 15.16! Since the air of No. 4 is guided, the air of No. 4 is guided. 1st port 1),,P,
From the case where the air is introduced indirectly through the piston 3
It is possible to effectively apply back pressure to the vehicle and make primary braking effective.

Further, the CPU 32 of the control device 19 sets the control mode of the valley operation section 1i according to the ideal deceleration curve C, and controls the intermittent operation means, continuous operation means, and secondary braking means according to the braking mode and the control mode. ? ri
Magnetic switching valve 17, 18 and electromagnetic brake 7 as secondary braking means
Since the piston rod 4 can be braked optimally according to the operating range, it is possible to brake the piston rod 4 optimally according to the operating range. 'It greatly reduces vibration and shock during braking compared to continuous braking using only magnetic brakes,
The piston rod stop positioning accuracy is significantly improved, and the life of the electromagnetic brake can be significantly extended. Further, the control device 19 of the above embodiment has the piston 3
The piston does not operate, does not stop at the target position, has a positioning error such as the piston exceeding the allowable speed, a start command is received without a target position input, or the target position memory is abnormal due to noise, etc. It has a means to detect system errors such as failure of memory backup.

FIG. 6 shows the second braking means, which is the primary braking means, in the embodiment shown in FIG.
Air source I4, 1st. The second braking line 15°I6 and the sub-electromagnetic switching valves 17 and 18 are omitted, and a flow adjustment means consisting of an electromagnetic switching valve f'loO and a throttle valve 101 for switching and controlling the flow rate is provided on the exhaust side of the air cylinder l. This is a modification example in which the primary braking means is used. That is, the first line 11 in FIG. Second
line! In addition, the speed control valves 25 installed in the main electromagnetic switching valves +3 are omitted, and the exhaust ports El+E2 of the main electromagnetic switching valves +3 are
It is connected to a 2-position, 3-port electromagnetic switching valve 100 that is switched by the primary braking signal S8 output from the control device 19, and a throttle valve 101 is provided in one exhaust line of this switching valve 100 to control the flow from the air cylinder 1. By discharging exhaust gas through this throttle valve +01, back pressure for braking is applied to the piston 3. With the above modification, the primary braking effect between the road and the road shown in FIG. 1 can be obtained. Moreover, instead of the primary braking means of the embodiment shown in FIG. 1, a control device is installed at the ball screw shaft end 6a of the air cylinder l! A power generating brake 36 (see FIG. 1) whose braking force can be adjusted by a primary braking signal from the piston rod 9 may be provided to apply primary braking to the piston rod 4.

FIG. 7 is a sectional view of a low clear air actuator provided in the pneumatic system of FIG. 6 in place of the air cylinder 1. FIG. This low clear air actuator 51 has an output shaft 56 which is a ball screw shaft having a ball screw 56c on the central axis inside a tube 52.1 of a main body 52, and has one end 5Ga of the output shaft 56 protruding outside the tube so as to be rotatable and movable in the axial direction. The piston 53 is supported by the tube 52a and has a ball nut 55 fixed to the ball screw 56c.
It is slidably fitted inside. In addition, the same armature 7a as shown in FIG. 6 is fixed to the output shaft 56 protruding from the other end of the tube 52a, and an electromagnet 7b is fixed to the other end of the tube so as to face the armature 7a.
611 is provided with the same [J-cli encoder 8 as in FIG. 6. Note that a rod 54 extending in the axial direction inside the tube is inserted into the through hole 53a of the piston 53 to prevent rotation. Note that this rotation preventing rod 54 can be omitted if the cross section of the tunib 52a and the piston 53 are elliptical or polygonal.

The first port of the rotary air actuator 51 with the above configuration! ]1. The first port P has a control device 19 shown in FIG.
Air source 9 via main solenoid switching valve 13
At the same time, the back pressure of the piston 53 is controlled by the control device 19 as described in 0j1 via the switching valve +00 and the calibration valve 101, which are the flow adjustment means, and the electromagnetic brake 7 is supplied with air. is controlled. Therefore, the low clear actuator 5! If the 171 standard rotation angle and decompression start rotation angle are set, the CPU 32 performs calculations necessary for control based on the rotation amount detection signal from the CI-Cliencoder 8, and based on the calculation results, the excitation signal The drive signals s,, s', are outputted to the main electromagnetic switching valve I3 through the generation section 34, and the primary braking signal S6 is outputted to the switching valve 100, respectively, and two signals are outputted to the electromagnetic brake 7 via the brake signal generation section 33.
The next braking signal S, is output, thereby causing the low clear air actuator 5! The output shaft 56a accurately and smoothly rotates to the target rotation angle and then stops.

According to the row clear actuator 51, intermediate positioning can be performed smoothly and with higher precision in the rotational direction.

FIG. 8 is a sectional view showing a modification of the row clear actuator 51 shown in FIG. 7. FIG. This low clear air actuator 61 is similar to the low clear air actuator shown in FIG. It has the same configuration as the actuator. Therefore, this rotary air actuator 61 also operates in the same manner as described above, and produces the same effects as described above. Note that the rotary air actuator 51.
It goes without saying that this invention can be applied not only to the pneumatic system shown in the figure, but also to the pneumatic system shown in FIG.

Note that the first aspect of the present invention. Regardless of the above embodiment, the second braking line is the first braking line. The sub-electromagnetic switching valve may be connected to the first port PI+P2. It may be a single two-position, three-port switching valve provided at the confluence of the second brake lines. Furthermore, it goes without saying that the braking mode by the control device of the present invention is not limited to that of the embodiment.

<Effects of the Invention> As is clear from the explanation in 1- below, the fluid device of the present invention has the following effects:
Piston C! The piston converts the reciprocating motion of the piston into the rotation of a ball screw shaft that is screwed into the piston via a ball nut, and is equipped with an electromagnetic brake that brakes the rotation of the ball screw shaft and a rotary encoder that detects the amount of rotation of the ball screw shaft. a first fluid pressure cylinder, and a first fluid pressure cylinder of this fluid pressure cylinder. A main electromagnetic switching valve that switches and connects a pressure source to the first port to reciprocate the piston, and a first brake line that connects to the flow path that connects to the first port, or a first brake line that connects to the flow path that connects to the first port in Section 4. 2 Braking line
A control device outputs a drive signal to the main electromagnetic switching valve, and also outputs a drive signal to the main electromagnetic switching valve and outputs a detection signal from the rotary encoder and a predetermined [1 standard value] to one of which is connected to a pressure source. According to the deviation from the signal and the operating range, a primary braking signal is output to the auxiliary electromagnetic switching valve to apply back pressure to the piston that moves back and forth, and a secondary braking signal is applied to the electromagnetic brake described in Section 2. Since a signal is output to smoothly stop the piston at the target position, the piston rod can be moved intermittently or continuously by any combination of primary braking by the sub-electromagnetic switching valve and secondary braking by the electromagnetic brake. Braking can be performed optimally depending on the operating range, and vibrations and shocks during braking are significantly reduced compared to conventional continuous braking using only electromagnetic brakes, and the piston rod stops.

In addition to significantly improving positioning accuracy, the life of the electromagnetic brake can be significantly extended.

In addition, instead of the above-mentioned fluid pressure cylinder, an output shaft made of a ball screw or the like is rotatably supported in the tube, and a screw fixed with a ball nut or the like fitted externally on the output shaft can be slid freely inside the tube. By providing a hydraulic rotary actuator that is fitted into the rotary rotary actuator, smooth rotation can be obtained, and intermediate positioning with higher accuracy in the rotational direction can be achieved.

[Brief explanation of the drawing]

Fig. 1 is a schematic diagram showing an embodiment of the fluid device of the present invention, Fig. 2 is a diagram showing control modes by the control device of the fluid device, and Figs. 3 to 5 show the flow of processing by the control device. 6 is a schematic diagram of a modified example showing primary braking by an exhaust throttle valve, and FIG. 7 is a cross-sectional view of a clear air actuator installed in the pneumatic system of FIG. 6 in place of the air cylinder. FIG. 8 is a sectional view of a modification of the row clear actuator. 1... Air cylinder, 2... Main body, 2a... Tube, 3... Piston, 4... Piston rod, 5
...Ball nut, 6...Ball screw shaft, 7...
Electromagnetic brake, 8... rotary encoder, 9...
1st air source, +3...main? 1 Magnetic switching valve, 14...Second air source, 15...Second braking line, 1G...Second
Braking line, +7. l, 8...Sub-m magnetic switching valve, [)1...1st port, Pl...1st braking pressure port, P,...1st port, Pt'...2nd braking pressure Port, 19...control device, 32...CPU5S,...detection signal, S3.
S3'... Drive signal, S,, S, +... Primary braking signal, S,... Secondary braking signal. Patent applicant: Daihatsu Diesel Co., Ltd. Agent: Patent attorney: Mr. Ao and one other person (Figure 4) Figure 5

Claims (7)

[Claims] (1) A piston with a hollow piston rod is slidably fitted into the tube of the main body, a ball nut is fixed coaxially to this piston, and an output consists of a ball screw shaft that is screwed into this ball nut. a fluid pressure cylinder having a shaft extending within the piston rod and rotatably but not axially movable attached to the main body; An electromagnetic brake that brakes rotation of the shaft, a rotary encoder that detects the amount of rotation of the output shaft of the fluid pressure cylinder as an electrical signal, and a pressure source switchably connected to a first port and a second port of the fluid pressure cylinder. a main electromagnetic switching valve that reciprocates the piston; a first brake line connected to a flow path connected to the first port of the fluid pressure cylinder; and a second brake line connected to the flow path connected to the second port of the fluid pressure cylinder. a sub-electromagnetic switching valve that connects a pressure source to either the first braking line or the second braking line, and outputs a drive signal that controls the main electromagnetic switching valve, and detects the detection from the rotary encoder. 1. Switching the auxiliary electromagnetic switching valve so as to apply back pressure to a piston driven by fluid pressure passing through the main electromagnetic switching valve, depending on the deviation between the signal and a signal representing a predetermined target value and the operating range. A fluid device comprising: a control device that outputs a secondary braking signal and a secondary braking signal for operating the electromagnetic brake to smoothly stop the piston at a target position. (2) In the fluid device according to claim 1, the first braking line connects a pressure source to a first braking pressure port provided at the end of the tube of the fluid pressure cylinder on the first port side, and the second braking line is the second tube of the hydraulic cylinder.
A fluid device that connects the second braking pressure port provided at the port side end and the pressure source. (3) In the fluid device according to claim 1 or 2, the control device calculates a target speed predetermined for each operation section based on an ideal deceleration curve and a detection signal of the rotary encoder. A fluid device comprising an intermittent actuation means that compares the piston speed with the target speed and intermittently outputs a primary braking signal to the sub-electromagnetic switching valve and a secondary braking signal to the electromagnetic brake when the piston speed is equal to or higher than the target speed. . (4) In the fluid device according to claim 1 or claim 2, the braking device includes a continuous operating means that continuously outputs a primary braking signal to the auxiliary electromagnetic switching valve at least in the initial stage of deceleration, and an ideal deceleration device. A target speed predetermined for each operating section based on the curve is compared with the piston speed determined from the detection signal of the rotary encoder, and when the piston speed is equal to or higher than the target speed, a secondary braking signal is sent to the electromagnetic brake. A fluid device including an intermittent actuation means that outputs an output intermittently. (5) The fluid device according to any one of claims 1 to 4, wherein a power generating brake capable of applying a braking force to the ball screw shaft is provided between the main body of the fluid pressure cylinder and the ball screw shaft. Device. (6) A piston with a hollow piston rod is slidably fitted into the tube of the main body, a ball nut is fixed coaxially to this piston, and an output consists of a ball screw shaft screwed into this ball nut. a fluid pressure cylinder having a shaft extending within the piston rod and rotatably but not axially movable attached to the main body; An electromagnetic brake that brakes the rotation of the shaft, a rotary encoder that detects the amount of rotation of the output shaft of the fluid pressure cylinder as an electrical signal, and a pressure source that is switchably connected to the first port and the second port of the fluid pressure cylinder. a main electromagnetic switching valve that reciprocates the piston; a flow rate adjustment means installed in an exhaust line connected to the exhaust port of the main electromagnetic switching valve; and a drive signal that controls the main electromagnetic switching valve; The flow rate is adjusted to apply back pressure to the piston driven by the fluid pressure passing through the main electromagnetic switching valve, depending on the deviation between the detection signal from the rotary encoder and a signal representing a pre-given target value and the operating range. A control device that outputs a primary braking signal for controlling the means and a secondary braking signal for operating the electromagnetic brake to accurately and smoothly stop the output shaft at a target rotation angle through reciprocating motion of the piston. A fluid device comprising: (7) In the fluid device according to claim 1 or claim 6, in place of the fluid pressure cylinder, an output shaft consisting of a ball screw or a helical spline is provided on the central axis within the tube of the main body, with one end thereof protruding outside the tube. A fluid pressure rotary actuator is provided, in which a piston is supported rotatably and immovably in the axial direction, and a piston having a ball nut or spline hole fitted externally on the output shaft is slidably fitted into the tube. Fluid equipment provided.