JPH0347760Y2 - - Google Patents

Description

[Detailed Description of the Invention] (Industrial Application Field) The present invention relates to a multiple pressure regulating device for adjusting and controlling the air pressure of each of a plurality of air tanks provided in a press machine to a predetermined pressure.

(Prior Art) A press machine uses a large air tank for a slide balancer, a dictation, an air tank for a blank holder, etc., and the set pressure of each tank must be changed every time a workpiece is changed. As a device for automatically controlling the pressure of a plurality of air tanks, the present applicant has already developed a device for automatically controlling the pressure of multiple air tanks.
proposed a multiple pressure control device disclosed in the publication.

In addition, since multiple press machines are sometimes used in combination on a line, it is common to change tank pressures at multiple locations at the same time when changing molds due to changes in workpieces.

As shown in Figure 5, the tank pressure of the slide balancer is reduced so that when the mold is removed, the balancer cylinder thrust balances with the weight of the slide without the mold, and after the mold is installed, The pressure is increased to a level that balances the weight of the slide plus the weight of the slide. In other words, the slide balancer tank pressure must be lowered and then raised.

On the other hand, the tank pressure of the duct and the tank pressure of the blank holder are respectively increased or decreased to the new installation pressure.

Conventionally, pressure in an air tank for a slide balancer has been lowered by releasing air pressure into the atmosphere.

It is not preferable from the viewpoint of energy saving to release the air pressure when replacing the mold in this way.

For this reason, recently, when changing molds, air pressure is supplied from a high-pressure air tank to another low-pressure air tank in order to save energy. Multiple pressure regulators have been proposed.

(Problem to be solved by the invention) However, in the conventional multiple pressure regulating device, in order to perform pressure regulation for energy saving, the air supply ports of each air tank are communicated with each other through mutual communication air supply piping, and The exhaust ports of each air tank were connected to each other by mutually communicating exhaust piping, and a switching valve was installed to connect and shut off the mutually communicating air supply piping and mutually communicating exhaust piping, resulting in double piping and complicated piping. In addition, there was a problem in that switching valves were required in many locations, increasing equipment costs. In addition, since air pressure was supplied from a high-pressure air tank to another low-pressure air tank by controlling a mechanical pressure regulating mechanism, highly skilled technology was required to set and adjust the pressure each time the mold was replaced. However, there was a problem that it was difficult to adjust the pressure.

An object of the present invention is to provide a multiple pressure regulating device for a press air tank that can easily perform energy-saving pressure regulation with simple piping.

(Means for Solving the Problems) To explain the configuration of the present invention to achieve the above object, the present invention utilizes the pressure in a plurality of air tanks corresponding to each of a plurality of air cylinders of a press machine from a pneumatic supply source. In addition to supplying air pressure from the air tank, in a press air tank multiple pressure regulating device that supplies and regulates air pressure from the air tank with high pressure to the air tank with low pressure, air is supplied from the air pressure supply source to each of the air tanks. Mutual communication piping that is connected to a common air supply piping and communicates only the air supply side of each of the air tanks with each other, and switching between conduction and disconnection between the air tanks and switching between exhaustion and disconnection of the air from each air tank to the atmosphere. a switching valve provided for each air tank in order to perform the above operations, and an air supply valve provided between the mutual communication pipe and the air pressure supply source to control supply and cutoff of air pressure from the air pressure supply source. and a valve controller for controlling each of the switching valves and the air supply valve, and a valve controller provided for each of the air tanks to detect the pressure in the corresponding air tank and output a pressure detection signal in accordance with the detected pressure. a common data input device for inputting the set pressure of each of the air tanks, a memory for storing each data inputted by the data input device, and the pressure detection output from each of the pressure detectors. A multiplexer that performs control to output signals in a predetermined order; and a multiplexer that outputs signals in a predetermined order; and a multiplexer that outputs signals in a predetermined order; and a multiplexer that outputs signals in a predetermined order; Determine whether the difference between the highest pressure in the air tank and the lowest pressure in each of the air tanks to be boosted is equal to or higher than a predetermined pressure, and if the difference is equal to or higher than the predetermined pressure, shut off the air supply valve via the valve controller. and a microprocessor that controls each of the switching valves to supply air pressure from the highest pressure air tank to the other air tanks via the mutual communication piping and performs pressure regulation control. It is.

(Function) With this configuration, in this invention, only the air supply side of each air tank communicates with each other.
The piping system is simplified without double piping. Also,
Since pressure regulation is controlled using a microprocessor, tank pressure, etc. can be easily set and controlled in accordance with the mold to be replaced. Further, the pressure setting contents can be stored in advance in a memory and then controlled by a program, so that the set pressure can be changed simply, quickly, and stably without any trouble.

(Example) Hereinafter, an example of the present invention will be described in detail with reference to the drawings, taking as an example a case where there are three air tanks for a press machine.

FIG. 1 is a circuit diagram showing a multiple pressure regulating device for an air tank for a press machine according to an embodiment of the present invention.

In the figure, the targets of pressure regulation by the multiple pressure regulation device according to this embodiment are slide balancer cylinder 1, dictation cylinder 2, blank holder cylinder 3, and slide balancer cylinder 1 of the press machine. A first air tank 41, which is a slide balancer tank, communicates with the piping 1a.
, a second air tank 42 which is a dictation air tank that communicates with the dictation cylinder 2 through a piping 2a, and a third air tank 43 which is a blank holder tank that communicates with the blank holder cylinder 3 through a piping 3a.

The switching valves 51, 52, 53 are connected to the air supply ports 51a, 52a, 53a and the tank port 51, respectively.
b, 52b, 53b and exhaust ports 51c, 52
It is a three-position demagnetizing type three-way valve having air supply ports 5 and 53c.
Only the tank ports 1a, 52c, and 53a are connected to each other through the mutual communication pipe 6, and each tank port 51b, 52b, and 5
3b is connected to the corresponding air tank 41, 42, 43 by piping 41a, 42a, 43a, respectively, and each exhaust port 51c, 52c, 53c opens to the atmosphere, and each air tank 4
1, 42, and 43, and to switch between discharging air from each air tank 41, 42, and 43 to the atmosphere, and switching between discharging the air to the atmosphere and blocking the same.

The air supply valve 7 connects the interconnecting pipe 6 and the air pressure supply source 8.
It is a two-way valve that controls the supply and cutoff of air pressure from the air supply pipe 7b, and the air supply port 7a is a common air supply pipe 7b.
and is connected to the mutual communication piping 6.

The valve controller 9 controls the switching valves 51, 52, 53 and the air supply valve 7. This valve controller 9
is a common control valve output circuit 10 and each switching valve 5
switching valve air supply solenoids 111, 112, 113 that control the air supply of the switching valves 51, 52, 53; and switching valve exhaust solenoids 121, 122, 123 that control the exhaust of the switching valves 51, 52, 53; , and an air intake solenoid 13 for controlling the air intake valve 7.

The pressure detectors 141, 142, 143 are provided for each air tank 41, 42, 43, and detect the pressure inside each corresponding air tank 41, 42, 43, and generate an electrical level pressure detection signal according to the detected pressure. This is a strain gauge type pneumatic transducer that outputs .

Input circuits 151 , 152 , 153 are for inputting pressure detection signals from each pressure sensor 141 , 142 , 143 to subsequent multiplexer 16 .

The multiplexer 16 is configured to time-divide each pressure detection signal and output it in a predetermined order.

A shared analog/digital converter (hereinafter referred to as an A/D converter) 17 is a multiplexer 1
Each analog pressure detection signal outputted from 6 is converted into each digital pressure detection signal.

The exhaust interlock setting section 18 is for setting the exhaust interlock, and the data input device 19 is for inputting data, and is for setting and controlling the set pressure of each air tank 41, 42, 43. This is for inputting various data such as setting constants for use and other inputs such as display units.

The multiple pressure regulating device also includes a memory 20 for storing each data inputted by the data input device 19, and a microprocessor 21.

As the memory 20, for example, a non-volatile memory or a backup memory is used.

The microprocessor 21 has an A/D converter 17
When the pressure of each air tank 41, 42, 43 is changed due to a work change, the pressure of each air tank 41, 42, 43 is adjusted based on the pressure detection signal given through the pressure detection signal and the set pressure stored in the memory 20. It is determined whether the difference between the highest pressure in the tank to lower the pressure and the lowest pressure in the tank to increase the pressure is greater than a predetermined pressure, and when the difference is greater than the predetermined pressure, the air supply is Valve 7 is kept in a cutoff state, and each switching valve 51, 52, 53 is controlled to supply air pressure from the tank with the highest pressure among the tanks whose pressure should be lowered to other air tanks whose pressure should be increased via mutual communication piping 6. It is now possible to perform pressure regulation control.

The output display 22 outputs information such as set values and tank pressure via the microprocessor 21.
CRT etc.

Next, the operation of the multiple pressure regulator shown in FIG. 1 will be explained with reference to the flowchart shown in FIG. 2.

In step ST1, all solenoids 111, 11
Turn off 2,113,121,122,123,13.

In step ST2, it is determined whether or not to change the pressure setting. If the pressure setting is to be changed, the process proceeds to step ST3; if the pressure setting is not to be changed, the process proceeds to step ST17.

In step ST3, the set pressure for each air tank 41, 42, 43 set by the data input device 19 is read.

In step ST4, the set pressure is stored in the memory 20.

In step ST5, it is determined whether or not new settings are to be started. If new settings have not been started, step ST3 is executed.
, and when starting a new setting, proceed to step ST6.

In step ST6, each air tank 41, 42,
Pressure sensor 141, 14 reads the pressure of 43.
2,143, input circuit 151, 152, 153,
This is performed by the microprocessor 21 via the multiplexer 16 and A/D converter 17. That is, the multiplexer 16 time-divides each pressure detection signal and outputs it in a predetermined order, the common A/D converter 17 converts this into digital pressure detection signals, and the microprocessor 21 outputs each pressure detection signal in a predetermined order. , 42, 43.

In step ST7, the current pressure of each air tank is
Calculate the differential pressure ΔPi between Ti and the set pressure Si. That is, ΔPi=Ti−Si is calculated.

In step ST8, the maximum pressure Tmax in the air tank where the differential pressure ΔPi is a positive number is determined.

In step ST9, the minimum pressure Tmin in the air tank where the differential pressure ΔPi is a negative number is determined.

In step ST10, it is determined whether or not Tmax-Tmin is greater than or equal to a predetermined constant (for example, 0.5 to 1.0 Kg/cm ² ). If it is determined to be greater than or equal to the value, the process proceeds to step ST11, and if it is determined to be less than that, the process proceeds to step ST11. Proceed to ST17.

In step ST11, the microprocessor 21
The air supply solenoid 1 for the air supply valve of the valve controller 9
3 to turn off the air supply valve 7. That is,
The air pressure supply source 8 is brought into a state in which no air pressure is supplied.

In step ST12, the differential pressure Fi between the maximum pressure Tmax and the set pressure Si of each air tank is determined. That is, find Fi=Tmax-Si.

In step ST13, the air tank with negative ΔPi (i.e., the air tank that should receive air pressure)
and Tmax air tank, the air supply solenoid of the air tank with positive differential pressure Fi and the switching valve for the Tmax air tank is turned on, and air pressure is supplied to the air tank that should receive air pressure from the Tmax air tank. In this way, the air pressure of the air tank having extra air pressure can be effectively used, and energy saving can be achieved.

In step ST14, it is determined whether or not the switching valve air supply solenoid is turned on at two or more locations.
If the number of points or more is exceeded, the process proceeds to step ST15, and if not, the process proceeds to step ST17.

In step ST15, it is determined whether or not to stop the energy-saving air supply operation. If it is determined to be stopped, the process proceeds to step 16, and if not, the process proceeds to step ST6.
Return to

In step ST16, all solenoids are turned off.

In step ST17, the air supply solenoid 13 for the air supply valve is turned on, and air pressure is supplied from the air pressure supply source 8.

Note that the flowchart after step ST17 shows the operation when the press machine starts operating after the replacement of the mold is completed.

In step ST18, the pressure of each air tank is read.

In step ST19, a comparison calculation is made between the set pressure of each air tank and the current tank pressure.

In step ST20, it is determined whether the exhaust interlock is on or off, and if it is on, the step
Proceed to ST21, and if it is off, proceed to step ST22.

In step ST21, only the air supply solenoid for the switching valve is turned on as necessary, the air supply port of the switching valve is opened, and the pressure of each air tank is adjusted.

In step ST22, all solenoids are operated as necessary to adjust the pressure in each air tank.

In step ST23, it is determined whether or not to stop the driving work. If the operation is to be stopped, the process proceeds to step ST16, and if not, the process returns to step ST2.

In addition, in the above embodiment, multiple pressure adjustment of each air tank of one press machine was explained, but multiple pressure adjustment of each air tank of multiple press machines can be performed in the same way. The switching valve 5 is
1, 52, and 53, a two-way valve 5a for air supply is provided for each air tank, as shown in FIGS. 3 and 4.
A two-way valve 5b for exhaust may also be used, and various other modifications are possible.

(Effects of the invention) As explained above, in the multiple pressure regulator according to the invention, only the air supply side of each air tank is connected to each other, so there is no need for double piping, and the piping system is simplified. Moreover, the required number of valves can be reduced accordingly, and equipment costs can be reduced. Further, in the present invention, since the pressure regulation is controlled by a microprocessor, there is an advantage that the setting and control of the tank pressure etc. can be easily performed depending on the mold to be replaced. Further, since the pressure can be set in memory, it is possible to set the pressure in advance and perform program control, which has the advantage that the set pressure can be changed without any trouble.

[Brief explanation of the drawing]

Fig. 1 is a circuit diagram showing an example of a multiplex pressure regulating device according to the present invention, Fig. 2 is a flowchart showing the operation of the device shown in Fig. 1, and Figs. 3 and 4 are about the switching valve of the present invention. FIG. 5 is a partial circuit diagram showing different embodiments of the press machine, and FIG. 5 is a pressure change diagram during mold removal, mold installation, and operation in each air tank of the press machine. DESCRIPTION OF SYMBOLS 1... Slide balancer cylinder, 2... Diction cylinder, 3... Blank holder cylinder, 13... Air supply solenoid for air supply valve, 16...
...Multiplexer, 17...A/D converter, 18
...Exhaust interlock setting unit, 19...Data input device, 20...Memory, 21...Microprocessor, 22...Output display, 41...First air tank (air tank for slide balancer), 4
2...Second air tank (air tank for diversion), 43...Third air tank (air tank for blank holder), 51, 52, 53...
Switching valve, 51a, 52a, 53a...air supply port, 51b, 52b, 53b...tank port,
51c, 52c, 53c...exhaust port, 6...
Mutual communication piping, 7... Air supply valve, 7b... Air supply piping, 8... Air pressure supply source, 9... Valve controller, 10
...Control valve output circuit, 111, 112, 113...
...Solenoid for switching valve, 121, 122, 123
...Exhaust solenoid for switching valve, 141, 142,
143...Pressure detector, 151, 152, 153
...Input circuit.

Claims (1)

[Scope of utility model registration request] The pressure in the plurality of air tanks corresponding to each of the plurality of air cylinders of the press machine is regulated by supplying air pressure from an air pressure supply source and by supplying air pressure from the air tank having a higher pressure to the air tank having a lower pressure. In the multiple pressure regulating device for press air tanks, mutual communication piping is connected to a common air supply piping that supplies air from the air pressure supply source to each of the air tanks, and communicates only the air supply side of each of the air tanks with each other; between a switching valve provided for each air tank to switch between conduction and cutoff between the air tanks, and switch between exhaustion from each air tank to the atmosphere and cutoff, and the mutual communication piping and the air pressure supply source; an air supply valve provided in the air tank for controlling supply and cutoff of air pressure from the air pressure supply source; a valve controller for controlling each of the switching valves and the air supply valve; and a valve controller provided for each of the air tanks. a pressure detector that detects the pressure in each corresponding air tank and outputs a pressure detection signal according to the detected pressure; a shared data input device that inputs the set pressure of each of the air tanks; and the data input device. a memory for storing each data inputted in the pressure sensor; a multiplexer for controlling output of the pressure detection signals outputted from each pressure sensor in a predetermined order; Based on the set pressure stored in the memory, when changing the set pressure of each of the air tanks, the difference between the highest pressure in each of the air tanks to be reduced and the lowest pressure in each of the air tanks to be increased is equal to or greater than a predetermined pressure. If the pressure is higher than a predetermined pressure, the air supply valve is cut off via the valve controller, and the switching valves are controlled to allow the mutual communication from the air tank with the highest pressure to the other air tanks. A multiple pressure regulating device characterized by comprising a microprocessor that supplies air pressure via piping and performs pressure regulation control.