JPH0348521A - Solid-state relay for driving solenoid valve - Google Patents

Abstract

PURPOSE:To prevent the malfunction caused by a noise and to rationally use the power source and the wiring by extending an optical fiber provided corresponding to a photodetector of a photocoupler, and providing the other terminal so as to correspond to a light emitting element of the photocoupler operated by a low voltage control circuit. CONSTITUTION:To valve device 12 brought to open/close operation by a solenoid 11, a solid-state device 13 is attached. A zero cross circuit 14 of this device is operated by a photodetector 15, and this photodetector 15 and a photodetector 16 for forming a photocoupler are extended and connected by an optical fiber for receiving no electric noise. In this state, an output side triggers a triac 18 by the circuit 14, and the solenoid connected in series to a power source 19 is opened and closed. Accordingly, since a low voltage control circuit 20 is brought to optical connection by the optical fiber 17, a noise of the power source 19 is not mixed at all. Also, since a power source line 19a is brought to wiring only to the solenoid 11 and the solid-state device attached directly thereto, the possibility of an erroneous wiring is also decreased.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a solid state relay that controls a solenoid valve that is driven to open and close by a solenoid.

The conventional type is a solid state relay (hereinafter abbreviated as SSR), as shown in Figures 1 to 3.
On the input side, as shown in FIG. 3, a triac 5 is switched via a zero cross circuit 4 using a light receiving element 3 such as a phototransistor that operates by light emission from a photocoupler light emitting element 2 that operates at a low voltage as an input circuit. The output side of this SSRI is generally a high-voltage general power source 6 and a solenoid 7 connected in series. and S
When the SRI is installed close to the low voltage control circuit 7 as shown in Fig. 1, the high voltage power supply line 6a containing external noise is connected to the SRI.
This noise enters the input side from where the wiring is connected to the output side of the SRI, causing the SSRI to malfunction.Also, as shown in Figure 2, the SSR 1 is attached directly to the solenoid 7, and the input line 1a of the SSRI is connected to the low voltage with an electric wire. Even when wiring is extended to the control circuit 7, the input line 1a comes close to the power supply line 6a at the SSRI position, making it impossible to prevent malfunctions due to noise.

The present invention has been made to improve the above-mentioned conventional situation. Embodiments of the present invention will be described below with reference to FIGS. 4 and 5.

A valve device 12 that is opened and closed by a solenoid 11
A solid state device 13 is attached to. The zero cross circuit 14 of the solid state device 13 includes a light receiving element l5.
The light-receiving element 15 and the light-emitting element 16, which acts as a photocoupler, are extended and connected by an optical fiber that is not affected by electrical noise. On the output side, a triac 18 is triggered by a zero cross circuit 14 to open and close a solenoid connected in series to a power supply 19.

Therefore, since the low voltage control circuit 20 is optically connected to the optical fiber 17, noise from the power supply 19a will not be mixed in at all. Further, since the power supply line 19a only needs to be wired to the solenoid 11 and the solid state device directly attached to the solenoid 11, the possibility of erroneous wiring is reduced, and since the power line 19a can be short, the cost of copper wiring can be saved. This means that A with a large starting inrush current
In the C-type solenoid, it is advantageous in terms of requiring thick copper wire to suppress voltage drop and having a margin for power supply capacity.

As explained above, according to the solid state relay for a solenoid valve of the present invention, the photocoupler light receiving element 15 is attached to the valve device 12 which is driven to open and close by the solenoid 11.
In the solid state relay for a solenoid valve, the solenoid valve is equipped with a solenoid valve l3 including a triac l8 triggered by a zero-cross circuit 14 which is mounted with a solenoid 11 and a triac l8 in series with a power supply 19. Light receiving element l
A photocoupler light-emitting element 1 whose other end is operated by a low voltage control circuit 20 by extending an optical fiber 17 installed opposite to the photocoupler 1
The structure is characterized in that the power supply line containing noise is connected to the solenoid 1l and the solid state device 13 directly attached to it, and the low voltage control circuit 20, which is susceptible to noise, is Since the light-receiving element 16 is placed on the low-voltage control circuit side and coupled with the optical fiber 17, there is no malfunction due to noise, and the power supply and wiring can be streamlined.

[Brief explanation of drawings]

1 to 3 show conventional examples, and FIG. 1 is a circuit diagram,
Figure 2 is a circuit diagram of another conventional example, and Figure 3 is a more detailed circuit diagram of Figures 1 and 2. 4 and 5 show embodiments of the present invention, with FIG. 4 being a detailed circuit diagram and FIG. 5 being a circuit diagram. DESCRIPTION OF SYMBOLS 11... Solenoid, 12... Valve device, 13... Solid state relay 14... Zero cross circuit 15... Light receiving element, 16... Light emitting element, I7... Optical fiber,
18...triac, 19...power supply, 20...
Low voltage control circuit.

Claims (1)

[Claims] 1) A solid-state device for a solenoid valve, which is made by attaching a solid-state device including a triac triggered by a zero-cross circuit equipped with only a photocoupler light-receiving element to a valve device that is driven to open and close by a solenoid, and connecting the solenoid and triac in series to a power source. A solid state relay for a solenoid valve, characterized in that, in the state relay, an optical fiber placed opposite to the light receiving element of the photocoupler is extended, and the other end is placed opposite to the light emitting element of the photocoupler operated by a low voltage control circuit.