JPH0750561Y2 - Pneumatic switching valve control device - Google Patents

Description

[Detailed description of the device]

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention has a multi-input multi-output type programmable controller for switching control of a pneumatic pressure switching valve to control a pneumatic cylinder for high speed forward movement, low speed forward movement, high speed backward movement or low speed backward movement and forward / backward movement. The present invention relates to a pneumatic switching valve control device that controls driving while switching speeds, especially pneumatic switching that prevents problems due to scan time delay when a programmable controller also drives and controls many pneumatic cylinders and peripheral device motors. The present invention relates to a valve control device.

[0002]

2. Description of the Related Art Conventionally, for example, Japanese Patent Laid-Open No. 2-15487.
As described in Japanese Patent Publication No. 3, there is known a pneumatic pressure switching valve capable of driving and controlling a pneumatic cylinder while switching the speed in four stages including high speed forward, low speed forward, high speed reverse or low speed reverse. It has been applied to various pneumatic cylinder drive systems.

As an example of this, as shown in FIG. 5, the piston rod 6 is changed by switching the supply / exhaust state to the cylinder chamber 60a of the pneumatic cylinder 60 and adjusting the supply / exhaust speed.
Pneumatic switching valve 1 for moving 4 in forward or backward at high speed or low speed
And a forward end limit switch LS1 that detects that the piston rod 64 has moved to the forward end, a reverse end limit switch LS2 that detects that the piston rod 64 has moved to the reverse end, and the piston rod 64 has the forward end. The forward limit switch LS3 for detecting the movement to the predetermined position in front and the piston rod 64
Based on the result of monitoring the input state from the limit switches LS1 to LS4 and the reverse limit front limit switch LS4 that detects that the vehicle has moved to the predetermined position before the reverse end, according to a predetermined order, high speed forward, low speed forward A pneumatic cylinder switching valve control device including a multi-input multi-output programmable controller 100 that outputs a speed instruction output of either high speed reverse or low speed reverse to the pneumatic pressure switching valve 1 is known. .

This programmable controller 100
When the dog 64a provided at the tip of the piston rod 64 contacts the forward end limit switch LS1, the two pilot solenoids 51 and 54 of the pneumatic switching valve 1 are switched to the control state for high speed reverse travel, and the piston rod 64 Even if the dog 64a comes into contact with the forward limit front limit switch LS3 as a result of moving backward, the control is continued as it is, and when the dog 64a further moves backward and comes into contact with the backward end front limit switch LS4, the pilot solenoid 51, 54 is switched to the control state for low speed reverse drive, and when the dog 64a contacts the reverse drive limit switch LS2 at the reverse drive end, the pilot solenoids 51, 5
4 is switched to the control state for high speed forward movement, and as a result of switching to forward movement, even if the dog 64a comes in contact with the rearward end front limit switch LS4, the control is continued as it is, and the dog 64a is further moved forward. When the limit switch LS3 is contacted, the pilot solenoids 51 and 54 are switched to the control state for low speed forward movement this time, and the following control is repeated to move the piston rod 64 to high speed forward → low speed forward → stop / high speed backward → It is possible to perform forward / backward control in four stages: low speed backward movement → stop / high speed forward movement.

In this way, the forward end limit switch L
Regarding S3 and the limit switch LS4 before the reverse end,
There is a case where the control state is not switched as soon as there is an input, but the control state is not switched as described in the above. Therefore, the multi-input multi-output programmable controller 100 used in this system
Monitors the input state in order and controls the drive state of the pneumatic switching valve 1 by various arithmetic processes.

[0006]

By the way, such a system drives and controls many other pneumatic cylinders and peripheral devices such as motors, rather than controlling only one pneumatic cylinder. It is generally configured to do so. Therefore, the multi-input multi-output type programmable controller used in such a system, in addition to the one related to the pneumatic cylinder 60, sequentially monitors the input states from a large number of limit switches and sensors to execute various arithmetic processing, It is configured to output according to the calculation result. Therefore, it takes a long time from the confirmation of one input state to the calculation output and the monitoring of the next input state. Even if the dog 64a of the piston rod 64 comes into contact with the forward end front limit switch LS3. Regardless, there was a variation in output based on the so-called scan time, in which the output for switching to low speed forward was delayed.

If there is such variation in the output for switching to the low speed movement, the deceleration start position varies, and it becomes impossible to smoothly stop the piston rod 64 to the planned position. For this reason, it is necessary to set the speed of high-speed movement to a low value, and there is a problem that the speed of driving the pneumatic cylinder cannot be sufficiently increased.

Therefore, it is possible to solve the problem based on the scan time, prevent the variation of the switching output to the low speed movement, and further increase the speed, and stick to the problem of the scan time as a whole system. The present invention has been completed for the purpose of providing an air pressure switching valve control device that does not cause a problem with respect to the control of.

[0009]

In order to achieve the above object, the pneumatic switching valve control device of the present invention is configured to switch the supply / exhaust state to the cylinder chamber of the pneumatic cylinder and adjust the supply / exhaust speed. By, the pneumatic switching valve for moving the piston rod forward or backward at high speed or low speed, the forward end detecting means for detecting that the piston rod has moved to the forward end, and the piston rod moving to the reverse end. A forward end detecting means for detecting the movement of the piston rod, a forward end front detecting means for detecting that the piston rod has moved to a predetermined position before the forward movement end, and a detection that the piston rod has moved to a predetermined position before the backward movement end. One of high speed forward, low speed forward, high speed reverse or low speed reverse, based on the result of monitoring the input means from each reverse detection end and each detection means in a predetermined order. In a pneumatic switching valve control device including a multi-input multi-output programmable controller that outputs a speed instruction output to a pneumatic switching valve, a multi-input multi-output programmable controller including forward end and reverse end detecting means. The main programmable controller that monitors the input state from the front end and the sub-programmable controller that monitors the input state from the forward end front end detection means, and the input from the forward end or rear end end detection means to the main programmable controller. Depending on the state, only the input state from the reverse end front detecting means while the piston rod moves from the forward end to the reverse end, and the input state from the forward end front detecting means while moving from the reverse end to the forward end If there is a sub-side monitoring state switching means that causes the sub programmable controller to monitor only In addition, the main programmable controller switches and outputs a forward or backward command to the sub programmable controller in response to detection of the forward end or the backward end, and the sub programmable controller outputs the forward or backward command to the forward end or the backward end. The present invention is characterized in that a high speed condition or a low speed condition depending on the input state from the front detecting means is taken into consideration, and the result is output to the pneumatic pressure switching valve as a speed instruction output.

According to the pneumatic switching valve control device of the present invention, the main programmable controller and the sub programmable controller are separated and the sub side monitoring state switching means is provided, so that the piston rod moves from the forward end to the backward end. While moving, in the sub programmable controller, only the input state from the backward end front detecting means is in the monitoring state. As a result, the detection state of the forward end front detecting means is disregarded, and only the fact that the piston rod has moved to the rearward end front is promptly detected without considering any temporal conditions up to that point. be able to. Moreover, the final speed instruction output to the pneumatic switching valve is
The sub-programmable controller side is output as either high-speed reverse or low-speed reverse by adding the high-speed or low-speed condition depending on the input state from the reverse-end front detection means to the reverse command output from the main programmable controller to the sub-programmable controller. Since it is configured to output in, the complicated judgment is not required and the delay based on the calculation time is eliminated.

On the contrary, while the piston rod is moving from the reverse end to the forward end, only the input state from the forward end front detecting means is in the monitoring state in the sub-programmable controller. It is possible to promptly detect only that the vehicle has moved and, as described above, it is possible to significantly reduce the calculation time until the final speed instruction output.

Therefore, the piston rod can be smoothly stopped at the forward end or the reverse end as planned, and the speed at which the piston rod moves from the forward end to the reverse end and from the reverse end to the forward end is significantly increased. No problem will occur even if the speed is increased.

It is possible to simply solve the problem of the scan time by providing a plurality of programmable controllers for each actuator of the pneumatic cylinder and other peripheral devices. You will lose control. In this respect,
According to the present invention, only the forward end front and rear end front detecting means for instructing deceleration of the pneumatic cylinder is irrelevant to the relative operation relationship in the overall control, which is a problematic part in terms of scan time. Is monitored by the sub-programmable controller, and the forward end and reverse end detection means, which are important for understanding the overall relative operation relationship, are handled by the main programmable controller that controls the entire control as in the past. , Such problems do not occur.

[0014]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Next, an embodiment to which the present invention is applied will be described with reference to the drawings. FIG. 1 shows the overall configuration of a pneumatic cylinder drive system as an embodiment, FIG. 2 shows an input / output connection diagram of the main programmable controller PC1 and sub programmable controller PC2 thereof, and FIG. 3 shows the structure of the pneumatic switching valve 1. FIG. 4 shows the respective control states.

In this pneumatic cylinder drive system, as shown in FIG. 1, the piston rod 64 is driven at high speed or low speed by switching the supply / exhaust state of the pneumatic cylinder 60 to the cylinder chamber 60a and adjusting the supply / exhaust speed. The forward / reverse limit switch LS1 for detecting that the air pressure switching valve 1 for moving forward or backward and the piston rod 64 have moved to the forward end.
A reverse end limit switch LS2 that detects that the piston rod 64 has moved to the reverse end, a forward end limit switch LS3 that detects that the piston rod 64 has moved to a predetermined position before the forward end, and a piston Limit switch LS4 before the reverse drive end that detects that the rod 64 has moved to a predetermined position before the reverse drive end
And forward limit and reverse limit switches LS1, LS2
Main programmable controller PC1 for monitoring the input state from the above and various peripheral devices (not shown) in a predetermined order, and the sub programmable controller for monitoring the input state from the forward end front and rear end front limit switches LS3, LS4 It is equipped with PC2.

First, the structure of the pneumatic switching valve 1 will be described with reference to FIG. The air pressure switching valve 1 has a cylindrical housing 2, and the housing 2 is composed of an upper adjusting main body 10 and a lower pressure reducing valve main body 30 connected thereto.

In the adjustment body 10, a bottom wall 12, an intermediate flange 13 and a top flange 14 are provided in the internal hole 11 of the housing 2, and the bottom wall 12 and the intermediate flange 13 are provided.
The first pressure regulating piston 15 is accommodated in the inner hole 11 so as to be able to slide in an airtight manner, and the second pressure regulating piston 16 is airtightly slid in between the intermediate flange 13 and the top flange 14. It is movably housed. The space between the bottom wall 12 and the first pressure adjusting piston 15 is a pressure receiving chamber 17, and
The space between the first and second pressure regulating pistons is a back pressure chamber 18, and the space between the second pressure regulating piston 16 and the top flange 14 is a regulation chamber 19.

The second pressure adjusting piston 16 comprises an outward flange portion 16a, a cylindrical portion 16b and a top wall portion 16c. The flange portion 16a slides on the inner hole 11, and the cylindrical portion 16b slides on the inner surface of the cylindrical portion 14b of the top flange 14. The upper end of the top wall portion 16c is a contact portion 16d extending outward. The outer peripheral surface of the cylindrical portion 14b is threaded, the lock nut 20 is attached thereto, and a circular stopper 21 is screwed into the cylindrical portion 14b on the upper side thereof. An adjustable clearance L is provided between the stopper 21 and the contact portion 16d of the second pressure adjusting piston 16. A screw-in handle 22 is attached to the center of the top wall 16c, and the lower end of the handle 22 urges the first pressure adjusting piston 15 downward via a spring retainer 23 and a first adjusting spring 24. A second adjusting spring 25 is further interposed between the first and second pressure adjusting pistons 15 and 16. Intermediate flange 13
A bleed hole 26 is provided in the.

In the main body 30 of the pressure reducing valve, the housing 2
In the inner hole 31 concentric with the inner hole 11 of the bottom flange 3
2, an intermediate flange 33 and an upper flange 34 are formed, and the upper flange 34 is integrally connected to the bottom wall 12. A circular second valve seat 36 and a circular first valve seat 35 are formed on the upper and lower portions of the inner end of the intermediate portion flange 33, respectively, and a circular secondary pressure chamber 37 is formed by the inner end of the intermediate portion flange 33. Are formed. A primary pressure chamber 38 is provided between the bottom flange 32 and the intermediate flange 33. A first valve body 39 is accommodated in the primary pressure chamber 38, and a lower portion thereof is a first valve body chamber 40 formed by the bottom flange 32. It can slide in an airtight manner. The valve head 39a of the first valve body 39 can come into contact with the first valve seat 35 of the intermediate flange 33. The first valve body 39 is provided with a valve body hole 39b that connects the secondary pressure chamber 37 and the first valve body chamber 40. The first valve body 39 is biased upward by the first valve body spring 43. An atmospheric pressure chamber 42 is formed between the intermediate portion flange 33 and the upper flange 34, and communicates with the atmosphere. Here the second valve body 41
Is housed. The upper portion of the second valve body 41 is capable of sliding in an airtight manner with respect to the second valve body chamber 44 formed by the upper flange 34. The valve head 41a of the second valve body 41 can come into contact with the second valve seat 36 of the intermediate flange 33.
The second valve body 41 is provided with a valve body hole 41 b that connects the secondary pressure chamber 37 and the second valve body chamber 44. The second valve body 41 is biased downward by the second valve body spring 45.

The upper end of the stem 46 is fixed to the central portion of the first pressure adjusting piston 15, and the intermediate portion of the stem 46 is the bottom wall 1.
2 is airtightly penetrated and is loosely inserted into the second valve body 41, and the lower portion has a large diameter to prevent the second valve body from falling.
Further, the lower end of the stem 46 can come into contact with the upper surface of the first valve body 39 when moving below the first pressure adjusting piston 15.

The primary pressure chamber 38 communicates with an air source 48 via a primary pressure chamber port 47, and the secondary pressure chamber 37 has a secondary pressure chamber passage 4.
It communicates with the cylinder chamber of the pneumatic cylinder not shown through 9. Further, the secondary pressure chamber 37 is a secondary pressure chamber port 50,
It is possible to communicate with the pressure receiving chamber 17 via a 3-port 2-position pneumatic solenoid valve (hereinafter referred to as a 3-port solenoid valve) 51 and a pressure receiving chamber port 52. The adjustment chamber 19 can communicate with the 5-port 2-position pneumatic solenoid valve (hereinafter referred to as 5-port solenoid valve) 54 through the adjustment chamber port 53, and the 5-port solenoid valve 54 is connected to the 3-port solenoid valve 51. Also, the air source 48
Is in communication with.

In the above configuration, the first state is shown in the illustrated state.
The valve body 39 is not in contact with the lower end of the stem 46, and receives the elastic force of the first valve body spring 43, so that the valve head 39a moves toward the first valve seat 35.
Is in contact with. In addition, the second valve body 41 is the second valve body spring 4
The valve head 41 a is in contact with the second valve seat 36 by the biasing force of No. 5. Further, the first pressure adjusting piston 15 is separated from the bottom wall 12 to form a pressure receiving chamber 17, the second pressure adjusting piston 16 is brought into contact with the top flange 14, and the adjusting chamber 19 is opened to the atmosphere, and its volume becomes small. ing. The pressure receiving chamber 17 and the secondary pressure chamber 37 communicate with each other through the secondary pressure chamber port 50, the 3-port solenoid valve 51, and the pressure receiving chamber port 52.

In this state, when the handle 22 is rotated to push down the first adjusting piston 15 and the stem 46 via the spring retainer 23 and the first adjusting spring 24, the second valve body 41 contacts the second valve seat 36. The first valve body 39 abuts the stem 46 and is pushed down. As a result, the primary pressure chamber 3
8 communicates with the secondary pressure chamber 37, and the primary air from the air source 48 flows into the secondary pressure chamber 37. Part of the air that has entered the secondary pressure chamber 37 flows into the pressure receiving chamber 17 via the secondary pressure chamber port 50, the 3-port solenoid valve 51 and the pressure receiving chamber port 52, and pushes up the first pressure adjusting piston. In response to this, the stem 46 rises,
The first valve body 39 also raises the first valve body 39 to contact the stem 46, and the pressure in the secondary pressure chamber 37 and the biasing force of the first adjusting spring 24 are balanced. The pressure in the secondary pressure chamber 37 can be adjusted by introducing pressurized air from the air source 48 into the adjusting chamber 19 via the 5-port solenoid valve 54 and pushing down the second pressure adjusting piston 16. The amount of movement of the second pressure adjusting piston 16 is restricted by the clearance L between the stopper 21 and the contact portion 16d of the second pressure adjusting piston 16. The clearance L can be adjusted by rotating the lock nut 20.

The operation of the pneumatic pressure switching valve 1 having the above construction will be described with reference to the combination of the pneumatic pressure switching valve 1 and the pneumatic cylinder 60 shown in FIG.
And Table 1 will be used. FIG. 4 schematically shows the operation of the pneumatic switching valve 1.

(A) shows the case where the piston 63 is rapidly raised, and the 3-port solenoid valve 51 (sol in Table 1).
1) The 5-port solenoid valve 54 (sol2 in Table 1) is energized, pressurized air is introduced from the air source 48 into the adjustment chamber 19 via the 5-port solenoid valve 54, and the second pressure adjusting piston 16
Is in the state of pressing down. Along with this, the first pressure adjusting piston 15 is pushed down, and the air in the pressure receiving chamber 17 is exhausted to the atmosphere through the 3-port solenoid valve 51 and the 5-port solenoid valve 54. Further, the first valve body 39 is pushed down by the stem 46 to connect the primary pressure chamber 38 and the secondary pressure chamber 37, the air of the air source 48 is supplied to the rod side of the pneumatic cylinder 60, and the piston 63 works. Rapidly increases with W. The pressure in the secondary pressure chamber 37 is equal to the primary pressure.

(B) shows the case of decelerating and raising the piston 63 and the case of stopping at the upper end of the pneumatic cylinder 60. The 3-port solenoid valve 51 is de-energized and the 5-port solenoid valve 54 is shown.
Is in the state of being energized. As a result, pressurized air is introduced from the air source 48 into the adjusting chamber 19 via the 5-port solenoid valve 54, and the second pressure adjusting piston 16 is pushed down. Along with this, the first pressure adjusting piston 15 is pushed down, and the pressure receiving chamber 17 communicates with the secondary pressure chamber 37 via the 3-port solenoid valve 51. The secondary pressure is adjusted to a high pressure by the first adjusting spring 24, the secondary pressure chamber 37 communicates with the primary pressure chamber 38 through a small gap, and the pressurized air of the air source 48 gradually flows out of the primary pressure chamber 38. Since it flows to the secondary pressure chamber 37 and further to the port 61 on the rod side of the pneumatic cylinder 60, the piston 63 decelerates and rises to reach the rising end.

(C) shows a case where the piston 63 is rapidly lowered, in which the 3-port solenoid valve 51 is energized and the 5-port solenoid valve 54 is de-energized. This makes the air source 4
8 pressurized air is 5 port solenoid valve 54, 3 port solenoid valve 5
1 is introduced into the pressure receiving chamber 17, and the first pressure adjusting piston 1
5 rises. Along with this, the second via the stem 46
The valve body 41 moves up, the secondary pressure chamber 37 and the atmospheric pressure chamber 42 communicate with each other, and the first valve body 39 moves up by the first spring 43, so that the secondary pressure chamber 37 and the primary pressure chamber 38 Is cut off, the air in the cylinder chamber on the rod 64 side of the pneumatic cylinder 60 is rapidly released into the atmosphere, and the piston suddenly descends.

(D) shows the case where the piston 63 is positioned at the deceleration lowering and lowering ends, and both the 3-port solenoid valve 51 and the 5-port solenoid valve 54 are de-energized. As a result, the pressurized air from the air source 48 is not supplied to the air pressure switching valve 1, and the secondary pressure chamber 37 is not connected to the secondary pressure chamber port 50 and the 3-port solenoid valve 51.
And the pressure receiving chamber 17 through the pressure receiving chamber port 52.
Therefore, the first pressure adjusting piston 15 rises by the exhaust air of the pneumatic cylinder 60, and the second valve body 4 passes through the stem 46.
Increase by 1. Since the secondary pressure is adjusted to a high pressure by the first adjusting spring 24, the amount of rise of the second valve body 41 is small, and the secondary pressure chamber 37 and the atmospheric pressure chamber 42 communicate with each other through a small gap, Since the air in the pneumatic cylinder 60 is decelerated from the secondary pressure chamber 37 and flows into the atmospheric pressure chamber 42, the piston 63 decelerates and descends to reach the descending end.

The first pressure-adjusting piston 15 of this embodiment may be replaced with a pressure-adjusting displacement means such as a diaphragm.

[0030]

[Table 1]

Next, the connection status of the control system will be described with reference to FIG. In the main programmable controller PC1, the forward end limit switch LS1 is connected to a dedicated input terminal IN11, the reverse end limit switch LS2 is also connected to a dedicated input terminal IN12, and other inputs (for example, start / stop switch and other various types) are connected. Various inputs such as various detection signals from the actuator are also connected to dedicated input terminals IN13, IN14 ,. Here, the forward end limit switch LS1 and the backward end limit switch LS2 are connected in a circuit connecting between the common terminal COM11 and the respective input terminals IN11 and IN12, and each is closed by the dog 64a of the piston rod 64. In this case, the power supply B installed in this circuit
The detection signal according to the voltage of 1 is input terminal IN11, IN12
Is configured to enter. The main programmable controller PC1 has its input terminals IN11 and IN1.
2, IN13, IN14, ... Are monitored in a predetermined order, and arithmetic processing according to each input state is performed.

On the other hand, the sub programmable controller P
At C2, the forward end front limit switch LS3 and the backward end front limit switch LS4 are connected to an input terminal IN21 common to them. The forward limit switch LS3 and the backward limit switch LS4 are respectively connected to the main programmable controller P.
It is also connected to the dedicated output terminals OUT11 and OUT12 of C1. The common terminal COM12 of the main programmable controller PC1 and the common terminal COM21 of the sub programmable controller PC2 are connected via the power supply B2. The power source B2 serves to act as an ON signal voltage supply source at the time of closing for the forward end frontward and reverse end front limit switches LS3, LS4, but the forward end and reverse end limit switches LS1,
It does not constitute a simple circuit such as the power source B1 for the LS2.

As described above, the main programmable controller PC1 is provided in the middle of the circuit from the power source B2 to the forward end front and rearward end front limit switches LS3, LS4.
Are inserted, and output terminals OUT11, OU
Limit switches LS3 and LS depending on the output state of T12
The power source B2 is connected to only one of the four. Output terminal OUT11 and output terminal OUT
12 is configured such that when one is in the on state, the other is in the off state.

Explaining concrete conditions, in the main programmable controller PC1, when the forward end limit switch LS1 is closed and an ON signal is inputted to the input terminal IN11, the reverse end limit switch LS2 is then closed. Until the output terminal OUT11 is turned off, the output terminal OU
Keep T12 on. Therefore, during this period, even if the forward end front limit switch LS3 is closed, an ON signal is not input to the common input terminal IN21 of the sub-programmable controller PC2, and the reverse end front limit switch LS4.
The ON signal is input to the common input terminal IN21 only when is closed. That is, during this period, in the sub programmable controller PC2, only the input state of the limit switch LS4 on the rearward travel end side is constantly monitored.

On the other hand, the main programmable controller P
When the reverse end limit switch LS2 is closed and an ON signal is input to the input terminal IN12, the C1 turns on the output terminal OUT11 until the forward end limit switch LS1 is closed next time, and the output terminal OUT12. Keep off.
Therefore, during this period, the sub programmable controller PC
In No. 2, only the input state of the forward end front limit switch LS3 is constantly monitored.

Further, the main programmable controller PC1 and the sub programmable controller PC2 are connected by main side output terminals OUTA and OUTB and sub side input terminals INA and INB. When the forward end limit switch LS1 is closed and an ON signal is input to the input terminal IN11, the main programmable controller PC1 turns off the output terminal OUTA until the next backward end limit switch LS2 is closed, When the output terminal OUTB is maintained on the one hand, while the reverse end limit switch LS2 is closed and the ON signal is input to the input terminal IN12, the output terminal OUTB is closed until the forward end limit switch LS1 is closed next time. OUTA turned on, output terminal OU
Keep TB off.

Sub programmable controller PC2
Is an input terminal IN connected to the output terminals OUTA and OUTB of the main programmable controller PC1.
Pilot solenoid 5 of pneumatic switching valve 1 depending on the input state to A and INB and the input state to common terminal IN21
In order to control 1, 54 to any combination of four types of (energization-energization), (non-energization-energization), (non-energization-non-energization), (energization-non-energization), two 3-port electromagnetic Valve 51
A control signal is output from the output terminal OUT21 for controlling (sol1) and the output terminal OUT22 for controlling the 5-port solenoid valve (sol2) to each pilot solenoid 51, 54.

Here, each of the limit switches LS1 to LS
4 state and each terminal IN11, IN12, OUT11, OUT
12, OUTA (INA), OUTB (INB), IN2
Table 2 shows the on / off states of 1, OUT21 and OUT22. In the table, “◯” indicates an on state and “x” indicates an off state. The pneumatic cylinder 60 operates in the order of the arrows in the table.

[0039]

[Table 2]

As described above, according to the present embodiment, the dedicated front sub-programmable controller PC2 is used for the forward end front and rear end front limit switches LS3 and LS4 for giving the timing of the deceleration instruction of the pneumatic cylinder 60.
In addition, while the piston rod 64 is moving from the forward end to the reverse end in the wiring relationship as shown in FIG. 2, only the input state from the reverse end front limit switch LS4 is changed from the reverse end. Since only the input state from the forward limit switch LS3 is monitored during the movement to the forward end, the timing of the deceleration instruction can be grasped without delay. In addition, the final speed instruction output to the pneumatic switching valve 1 is sent from the main programmable controller PC1 to the sub programmable controller PC2.
Is configured to be output on the side of the sub-programmable controller PC2 as an output of either high speed reverse or low speed reverse in consideration of the high speed or low speed condition depending on the input state from the reverse end front limit switch LS4 Therefore, the delay based on the calculation time is also eliminated.

On the contrary, while the piston rod 64 is moving from the rearward end to the forward end, the forward limit switch LS3 is located in front of the forward end.
Since only the input state from is in the monitoring state, it can be promptly detected that the piston rod 64 has moved to the front end of the forward end, and the calculation time until the final speed instruction output can be obtained as described above. It can be greatly shortened.

Therefore, the piston rod 64 can be smoothly stopped at the forward end or the backward end as planned, and the speed of movement from the forward end to the backward end before and from the backward end to the forward end before is greatly increased. No problem will occur even if the speed is increased.

In addition, in this embodiment, a plurality of programmable controllers are provided for each actuator of the pneumatic cylinder 60 and other peripheral devices, so that the problem of scan time is not simply solved, but from the viewpoint of scan time. Limit switch L for advancing front end and rearward end, for instructing deceleration of pneumatic cylinder 60, which is a problematic part but is irrelevant to the relative operating relationship in the overall control.
Only S3 and LS4 are sub-programmable controller P
The main programmable controller PC1, which controls the overall control in the same manner as the conventional one, takes charge of the forward end and reverse end limit switches LS1 and LS2, which are important for grasping the relative operation relationship of the entire system by monitoring with C2. Therefore, the problem of the scan time is solved, and at the same time, a new problem that the relative operation relation of the entire system cannot be controlled does not occur.

As a result, the entire system can be drive-controlled while accurately grasping the relative operating relationship as in the conventional case, and in the pneumatic cylinder 60, the piston rod 64 is moved forward or backward as planned. It can be stopped smoothly, and the speed of movement from the forward end to the front of the reverse end and from the rear end to the front of the forward end can be significantly increased, enabling efficient operation of the entire system. can do.

Although one embodiment of the present invention has been described above, the present invention is not limited to this, and various modes can be adopted without departing from the scope of the invention.

[0046]

As described above, according to the pneumatic pressure switching valve control device of the present invention, the problem due to the scan time is solved, the variation of the switching output to the low speed movement is prevented, and the speed is further increased. You can Moreover, the problem of control of the entire system does not occur due to the problem of scan time.

As a result, the entire system can be drive-controlled while accurately grasping the relative operation relationship as in the conventional case, and in the pneumatic cylinder, the piston rod is smoothly moved at the forward end or the backward end as planned. The speed of moving from the forward end to the front of the reverse end and from the reverse end to the front of the forward end can be significantly increased, enabling efficient operation of the entire system. You can

[Brief description of drawings]

FIG. 1 is an overall configuration diagram of a pneumatic cylinder drive system of an embodiment.

FIG. 2 is an input / output connection diagram of the main programmable controller and the sub programmable controller.

FIG. 3 is a vertical cross-sectional view showing the structure of an air pressure switching valve according to an embodiment.

FIG. 4 is a schematic diagram showing an operating state of an air pressure switching valve.

FIG. 5 is an overall configuration diagram of a conventional pneumatic cylinder drive system.

[Explanation of Codes] 1 ... Pneumatic switching valve, 39 ... First valve body, 41 ...
Second valve body, 48 ... Air source, 51 ... 3-port solenoid valve, 54 ... 5-port solenoid valve, 60 ... Pneumatic cylinder, 60a ... Cylinder chamber, 64 ... Piston Rod, 64a ... Dog, LS1 ... Forward end limit switch, LS2 ... Reverse end limit switch, LS3
・ ・ ・ Front limit switch before forward end, LS4 ・ ・ ・ Limit switch before reverse end, OUT ・ ・ ・ Output terminal, PC
1 ... Main programmable controller, PC2
..Sub-programmable controller, W ... Work

Claims (1)

[Scope of utility model registration request] 1. An air pressure switching valve for moving a piston rod forward or backward at a high speed or a low speed by switching a supply / exhaust state to / from a cylinder chamber of an air pressure cylinder and adjusting a supply / exhaust speed, and a piston rod moving forward. Forward end detecting means for detecting that the piston rod has moved to the end, backward end detecting means for detecting that the piston rod has moved to the rearward end, and detecting that the piston rod has moved to a predetermined position before the forward end Based on the result of monitoring the input state from the forward end front detecting means, the reverse end front detecting means for detecting that the piston rod has moved to a predetermined position before the rear end, and the input state from each detecting means in a predetermined order. , A multi-input multi-output programmable controller that outputs a speed instruction output of high speed forward, low speed forward, high speed reverse or low speed reverse to the pneumatic switching valve In a pneumatic switching valve control device equipped with a multi-input multi-output type programmable controller, a main programmable controller that monitors the input state from the forward end and reverse end detection means, and a front end before and rear end detection It is divided into a sub-programmable controller that monitors the input state from the means, and depending on the input state from the forward end or backward end detection means to the main programmable controller, while the piston rod moves from the forward end to the backward end, the backward end is in front. Only the input state from the detecting means, while having a sub-side monitoring state switching means for making the sub programmable controller monitor only the input state from the forward end front detecting means while moving from the reverse end to the forward end, The main programmable controller responds to the detection of the forward end or the reverse end by detecting the subprogram. Forward or switching outputs reverse instruction to Ma logic controllers, sub programmable controller, in the forward or reverse instruction,
Pneumatic switching valve control characterized by being configured to take into account a high speed or low speed condition depending on an input state from the forward end front or rearward end front detection means, and to output the result as a speed instruction output to the pneumatic pressure switching valve. apparatus.