JPH0125370Y2 - - Google Patents

Description

[Detailed explanation of the invention] (a) Industrial application field This invention relates to a switching device such as a limit switch used for controlling equipment, automation line control, etc. The present invention relates to a switching device that can transmit switching operations to an external control circuit without wiring.

(b) Conventional technology Conventionally, there is a switching device having a structure shown in FIG.

This opening/closing device is a limit switch that detects an external force 3 using an actuator 2 provided at one end of a case 1, and transfers the detected external force 3 to a built-in switch via an external force transmission mechanism 4 provided inside the case 1. 5, and by the opening/closing operation of the built-in switch 5, an opening/closing signal is transmitted to an external control circuit 6 to be controlled.

In addition, the means for connecting the built-in switch 5 inside the case and the control circuit 6 outside the case is to take one end of the conductor 7 through the side wall through-hole of the case 1 and connect it to the terminal 8 of the built-in switch 5 inside. , the other end is connected to an external control circuit 6, and a sealing member 9 is installed in the above-mentioned horizontal through hole.

This type of opening/closing device (limit switch) is generally used in adverse environments such as machine oils and metal cutting powder, and therefore, importance is placed on sealing performance.

(c) Problems to be solved by the invention However, the above-mentioned switchgear currently does not provide sufficient sealing performance at the attachment part of the seal member 9 and its conductor insertion part, so it may cause malfunction of the built-in switch 5 or This often caused poor contact.

In addition, mechanical strength is often required at the installation location, which increases the size of the structure itself, and also requires cumbersome work such as having to screw together both ends of multiple conductors. It required

Therefore, this idea incorporates an electrical signal transmission circuit for the external control circuit inside the switchgear, which allows the control circuit to be controlled without wiring without forming a transverse part in the case. The purpose is to provide a switchgear that is easy to adjust and replace, and is easy to use.

(d) Means for solving the problem This invention is an opening/closing device that opens and closes a switch built in the case by operating an actuator provided in the case, and is a removable switch that constitutes the case. Inside the top cover,
The switching device is characterized in that it houses an electrical signal transmitting circuit that wirelessly transmits electrical signals driven by the switch to an external control circuit.

(E) Function According to the switchgear of this invention, the electrical signal of the switch operated by the actuator is wirelessly transmitted to the external control circuit by the electrical signal transmitting circuit.

Since the electric signal transmission circuit is housed inside the top cover, maintenance inspection, circuit adjustment, and parts replacement can be performed by removing the top cover.

(f) Effects of the invention As a result of the above, according to this invention, the electric signal of the switch of the switchgear can be wirelessly transmitted to the external control circuit, so there is no need to connect the switchgear and the control circuit with conductive wires. This eliminates the need for a horizontal through-hole for inserting a conductor into the case and a sealing member for the side through-hole, which simplifies the components of the switchgear, eliminates the risk of sealing deterioration, and reduces wiring work. becomes unnecessary.

Furthermore, since the electrical signal transmission circuit is housed inside the top cover, by removing the top cover and assembling the transmission circuit, assembly work efficiency is improved and, for example, the oscillation frequency can be changed or adjusted. Maintenance and inspection such as replacement of circuit parts is easy, and it has the effect of being user-friendly.

(G) Embodiment An embodiment of this invention will be described below in detail based on the drawings.

The drawing shows a limit switch as an example of an opening/closing device, and in FIG.
It consists of a built-in switch 5 that opens and closes according to the operation of the built-in switch 5, and an oscillation circuit 10 for transmitting electrical signals that outputs a signal to an external control circuit (not shown) to be controlled based on the opening and closing of this built-in switch 5. .

The above-mentioned oscillation circuit 10 constitutes a part of the case 1 of the limit switch, and is housed inside a top cover 11 that can be attached and detached with screws, for example, to improve signal transmission efficiency. 10
and the built-in switch 5 are electrically connected via a coil 12.

The external force transmission mechanism 4 described above is the same mechanism as that normally built in a limit switch, and has a rotation shaft 1 connected to the base end of the actuator 2.
6 and an actuating piece 17 that moves forward and backward in conjunction with the rotation shaft 16, and the built-in switch 5 is opened and closed by moving the actuating piece 17 forward and backward.

FIG. 3 shows the above-mentioned oscillation circuit 10, 13 is a power supply, 14 is a crystal resonator, 15 is an FET, R1, R
2 is a resistor, C is a capacitor, and L is a coil, which constitute a well-known Pierce oscillation circuit.

In the limit switch configured in this way, when an external force is detected by the actuator 2, the built-in switch 5 opens and closes.
The opening/closing signal is transmitted to the oscillation circuit 10 via the coil 12, and from there to the external control circuit 6, where the control circuit 6 is controlled.

Therefore, according to this embodiment, the built-in switch 5
Since the electric signal can be wirelessly transmitted to the external control circuit 6, there is no need to connect the switchgear and the control circuit with a conductor, and in order to insert the conductor into the case 1, there is no need to use a lateral through-hole or its lateral through-hole. This eliminates the need for partial sealing materials, which simplifies the components of the switchgear and eliminates any risk of deterioration of sealing performance.Furthermore, installation can be completed by simply placing the limit switch in the designated location. This eliminates the need for the current troublesome wiring work.

In addition, since connection using conductive wires is not required, the possibility of incorrect wiring is also eliminated.

Furthermore, since the oscillation circuit 10 is housed inside the top cover 11, by removing the top cover 11 and assembling the oscillation circuit 10, assembly work efficiency is improved, and for example, the oscillation frequency can be changed. Maintenance and inspection such as adjustment and replacement of circuit parts are easy, and it has the effect of being easy to use.

In addition, in the above-mentioned embodiment, an example was shown in which an oscillation circuit of a Pierce circuit was built in as an electric signal transmission circuit, but it is not limited to this, and transmission control using light with a built-in light emitting element is also possible.
Further, it is also possible to perform transmission control using ultrasonic waves with a built-in ultrasonic ceramic microphone, and this invention is not limited to the configuration of the above-described embodiment.

[Brief explanation of the drawing]

The drawings show an embodiment of this invention, with FIG. 1 being an explanatory diagram of a conventional switching device, FIG. 2 being a longitudinal side view of a limit switch, and FIG. 3 being an oscillation circuit diagram of the limit switch. 1... Case, 2... Actuator, 5...
Built-in switch, 6...control circuit, 10...oscillation circuit, 11...top cover.

Claims (1)

[Scope of Claim for Utility Model Registration] An opening/closing device that opens and closes a switch built in the case by operating an actuator provided in the case, which includes: A switchgear housing an electrical signal transmitting circuit that wirelessly transmits electrical signals driven by the switch to an external control circuit.