JPH042834B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to an electromagnetic three-way valve that supplies or excludes air pressure from a supplied device operated by compressed air. In particular, it is used in the structure of electromagnetic three-way valves that can finely control the pumping speed.

The present invention is suitable for use in automotive control devices and other mechanical automatic control devices.

[Conventional technology]

A three-way valve has traditionally been used as a means to supply or remove air pressure to a supplied device (such as an air cylinder) that operates by supplying or exhausting compressed air, and is controlled by electromagnetic control. 2. Description of the Related Art As a three-way valve, a solenoid valve that performs on/off operation by turning on and off a single drive current is widely known.

In this case, if it is necessary to control the operating pressure and operating time during the operating process when the supplied device is exhausted, an air restriction may be provided at the exhaust port of the solenoid valve, or a separate air restrictor may be installed in the exhaust passage. Some pumps use a ball valve supported by a coil spring installed to adjust the exhaust speed.

[Problem that the invention seeks to solve]

However, in the above method, each adjustment is fixedly set in advance, and the exhaust speed cannot be changed while the entire system is in operation. This is extremely inconvenient in devices where mechanical operations are precisely controlled by a control circuit including a microprocessor.

An object of the present invention is to provide an electromagnetic three-way valve that can control the exhaust speed from the supplied device using a signal.

[Means for solving problems]

The first invention provides an input port connected to compressed air pressure, a supply port connected to a device to which air pressure is supplied, an exhaust port connected to atmospheric pressure, a primary electromagnetic coil, and a device driven by the primary electromagnetic coil. , an electromagnetic three-way valve including a primary movable core that sets a state in which the input port and the supply port communicate with each other and a state in which the supply port and the exhaust port communicate with each other, the electromagnetic three-way valve provided in the vicinity of the passage of the exhaust port. It is characterized by comprising a secondary electromagnetic coil, and a secondary movable core driven by the secondary electromagnetic coil to set whether or not the passage of the exhaust port is throttled.

In the present invention, it is preferable that the contact surface between the secondary movable core and the passage cap is metal contact.

The second invention has an input port connected to compressed air pressure, a supply port connected to a device to which air pressure is supplied, an exhaust port connected to atmospheric pressure, a primary electromagnetic coil, and a device driven by the primary electromagnetic coil. , an electromagnetic three-way valve including a primary movable core that sets a state in which the input port and the supply port communicate with each other and a state in which the supply port and the exhaust port communicate with each other, the electromagnetic three-way valve provided in the vicinity of the passage of the exhaust port. It includes a secondary electromagnetic coil, and a secondary movable core that is driven by the secondary electromagnetic coil and sets whether or not the passage of the exhaust port is throttled, and further, a current that is periodically connected and disconnected to the secondary electromagnetic coil. The driving circuit is characterized in that the driving circuit includes means for variably setting the ratio between the on-time and off-time of the current.

[Effect]

A secondary movable core having a secondary electromagnetic coil and a narrow exhaust passage driven by the secondary electromagnetic coil is provided near the exhaust port of the main body of the electromagnetic three-way valve. One status of this secondary electromagnetic coil is to widen the exhaust passage by means of a throttle provided in the secondary movable core to maximize the exhaust speed at which exhaust air from the supplied device is exhausted. When the secondary movable core is in the other status, the aperture provided with the secondary movable core closes off the wide exhaust circuit, so that the exhaust speed is minimized. Furthermore, by driving the secondary electromagnetic coil with a current that periodically connects and disconnects, and by setting the on-off time and off-time of the current to be variable, the exhaust speed can be adjusted to any speed between the minimum and maximum values mentioned above. can be controlled.

〔Example〕

Embodiments of the present invention will be described with reference to the drawings.

FIG. 1 is an operational schematic diagram for explaining the above embodiment. In Fig. 1, the main body 1 of the electromagnetic three-way valve includes an input port 2 into which compressed air pressure is input, a supply port 3 which communicates with a supplied device (not shown), an exhaust port 4 which communicates with atmospheric pressure, and a switch means SW1. The primary movable core 6 includes a primary electromagnetic coil 5 that is energized and a primary movable core 6 that is driven by the primary electromagnetic coil 5.
and is supported by a spring 6b.

Primary electromagnetic coil 5 by switch means SW1
When energized, the primary movable core 6 moves against the spring 6b, and the first valve seat 6c with a gas-tight component is pulled away from the input port 2 and the second valve seat 6c, which also has a gas-tight component, is moved away from the input port 2. The valve seat 6d closes the intermediate port 7a of the fixed valve 7. Therefore, the compressed air pressure flowing in from the input port 2 passes through the supply port 3 via the chamber A, and flows into a supplied device (not shown). At this time, the pressure in chamber A is the port 6a of the primary movable core 6.
However, since the intermediate port 7a is closed by the valve seat 6d, the compressed air is not discharged to the atmosphere.

The switch means SW1 opens and the primary electromagnetic coil 5
When energized, the primary movable core 6 is returned to its position by the spring 6b, and the input port 2 is closed by the first valve seat 6c, cutting off the input of compressed air pressure. In addition, as shown in FIG. 1, the air pressure in the supplied device is reduced to atmospheric pressure by the passage from the supply port 3 through the port 6a of the primary variable core, the intermediate port 7a of the fixed valve 7, and the exhaust port 4. released inside.

Here, the features of the present invention are that, as shown in FIG. A secondary movable core 9 having two types of passages 9a and 9b is provided to set the presence or absence of a throttle, that is, to vary the cross-sectional area of the exhaust passage.

Furthermore, as a second invention of the present invention, a drive circuit 10 is provided which periodically supplies a disconnection current to the secondary electromagnetic coil 8 and can variably set the ratio of the duration of each of the connection and disconnection. It's where it's set up.

Next, referring to FIG. 1, the operation of the exhaust state of this embodiment in the case of a simple disconnection operation of the switch means SW2 of the drive circuit 10 will be explained.

If the switch means SW2 is now open and the secondary electromagnetic coil 8 is not energized, the secondary movable core 9
is pulled away from the end of the intermediate port 7a of the fixed valve 7 by a spring 9c. Therefore, the air pressure from the intermediate port 7a enters the chamber C, passes through two types of ports 9a and 9h provided in the secondary movable core 9, and is discharged to the atmosphere via the exhaust port 4. Air resistance at this time is small.

On the other hand, when the secondary electromagnetic coil 8 is energized,
Since the secondary movable core is in contact with the end of the intermediate port 7a of the fixed valve 7 against the spring 9c, the exhaust gas from the intermediate port 7a is not directly exhausted from the port 9b. Therefore, when the secondary electromagnetic coil 8 is energized, air is exhausted only from the port 9a, so air resistance is large, and the exhaust speed is slower than when the secondary electromagnetic coil 8 is not energized, as described above. .

Next, to explain the operation of the drive circuit 10, this drive circuit 10 includes two potentiometers PM1 and
PM2 is provided, the disconnection cycle is changed by the potentiometer PM1, and the potentiometer PM2
The connection/disconnection ratio is changed by By operating these, the drive current to the secondary electromagnetic coil 8 is periodically supplied in a pulsed manner, as shown in FIG. 2, and the length and interval of the waveform can be set arbitrarily. Time t ₁ in FIG. 2 indicates the contact time during which the secondary electromagnetic coil 8 is energized, and time t ₂ indicates the disconnection time during which the secondary electromagnetic coil 8 is not energized.

In this case, the ratio of the sum of each time t ₁ and t ₂ to the total exhaust time T, that is, the duty ratio
If the proportion occupied by t ₁ is large, the pumping speed will be slow, and if the proportion occupied by t ₂ is large, the overall pumping speed will be faster. Thereby, the exhaust speed from the supplied device can be arbitrarily varied.

Even if the secondary movable core performs intermittent repetitive motion at this time, the exhaust flow from the supplied device is smoothed due to the roughness and radius of curvature of the inner surface of the exhaust passage and the air restrictors 15 and 16.

From the top of the component structure of this embodiment, the secondary movable core 9 is configured to make metal contact with the end of the intermediate port 7a of the fixed valve 7, which is a passage cap. This is the first
As shown in the figure, compressed air pressure comes into direct contact with the valve seats 6c and 6d from the input port, so it is necessary to prevent air leakage, but the contact surface with the end of the intermediate port 7a is Since it is on the exhaust passage side, even if a small amount of air leaks, it will not greatly impede the effectiveness of the electromagnetic three-way valve of the present invention. Moreover, as shown in FIG. 2, this component frequently repeats contact operations during the exhaust stroke, so if the surface is not metal, it will wear out quickly and shorten the life of the component.

FIG. 3 shows an explanation of a drive circuit according to a second embodiment of the present invention.

When the central controller 11 of the entire system including supplied devices (not shown) sends a pulse signal to the drive circuit 10 according to a program, this pulse signal causes the switch means SW2 to intermittently activate the secondary excitation coil (not shown). to drive. As shown in Figure 4, this pulse signal controls the pumping speed of the electromagnetic three-way valve in stages according to the density of the pulses within a unit time, and when the pulse waves are dense, they are coarse. The exhaust speed will be slower than that.

With such a configuration, the pumping speed can be controlled nonlinearly with respect to time.

Further, since the configuration shown in FIG. 1 is an explanatory schematic diagram, each valve is illustrated as being moved by a spring, but it may also be implemented as a diaphragm valve, for example.

[Effects of the Invention] As described above, according to the present invention, the exhaust speed of the exhaust pressure from the supplied device can be arbitrarily controlled. In addition, the pumping speed can be variably controlled even during operation. Therefore, there is an effect that the drive of the supplied device during the exhaust stroke can be precisely controlled.

[Brief explanation of drawings]

FIG. 1 is an explanatory schematic diagram of a first embodiment of the present invention. FIG. 2 is a time chart for driving the secondary electromagnetic coil of the above embodiment. FIG. 3 is an explanatory diagram of a drive circuit according to a second embodiment of the present invention. FIG. 4 is a time chart for driving the secondary electromagnetic coil in the above embodiment. 1... Main body, 2... Input port, 3... Supply port, 4... Exhaust port, 5... Primary electromagnetic coil, 6... Primary movable core, 6a, 9a, 9b...
Port, 6b, 9c... Spring, 6c, 6d... Valve seat, 7... Fixed valve, 7a... Intermediate port, 8
...Secondary electromagnetic core, 9...Secondary movable core, 10...
... Drive circuit, 11 ... Central control unit, 15, 16
...Air throttle, 17...Stopper ring, A,
B, C...chamber, PM1, PM2...potentiometer, SW1, SW2...switch means, T...
Total exhaust time, t ₁ ... contact time, t ₂ ... disconnection time.

Claims (1)

[Claims] 1. An input port connected to compressed air pressure, a supply port connected to a device to which air pressure is supplied, an exhaust port connected to atmospheric pressure, a primary electromagnetic coil, and a device driven by the primary electromagnetic coil. and a primary movable core that sets a state in which the input port and the supply port communicate with each other and a state in which the supply port and the exhaust port communicate with each other. A three-way electromagnetic valve comprising: a secondary electromagnetic coil; and a secondary movable core driven by the secondary electromagnetic coil to set whether or not the passage of the exhaust port is throttled. 2. An input port connected to compressed air pressure, a supply port connected to a device to which air pressure is supplied, an exhaust port connected to atmospheric pressure, a primary electromagnetic coil, and an input port that is driven by this primary electromagnetic coil and connected to the input port. A three-way electromagnetic valve including a primary movable core that sets a state in which the supply port communicates with the supply port and a state in which the supply port and the exhaust port communicate with each other, the secondary electromagnetic coil provided near the passage of the exhaust port; and a secondary movable core that is driven by the secondary electromagnetic coil and sets whether or not the passage of the exhaust port is throttled, and further includes a drive circuit that supplies a current that periodically connects and disconnects the secondary electromagnetic coil. An electromagnetic three-way valve, characterized in that the drive circuit includes means for variably setting the ratio of the on-time and off-time of the current. 3. The electromagnetic three-way valve according to claim 1, wherein the contact surface between the secondary movable core and the passage cap is metal contact.