JPH03231406A - Electrical connector with non-energized contact - Google Patents

Abstract

PURPOSE:To prevent arc from occurring when connecting and disconnecting a contact by winding coils around a contact at a power supply side and that at a load side of a ferromagnetic material. CONSTITUTION:A contact at a power supply side 1 and a contact at a load side 2 are formed by a silicon steel plate laminated body or a permaloy, etc., and coils 3 and 4 are wound by insulating them from a contact. When the coil 3 is connected to a power supply 5 and a magnetic pole at the load side contact 2 is connected to that of the contact at the power supply side 1, a closed magnetic path is formed, the coils 3 and 4 are coupled magnetically, voltage is induced at the coil 4, and energy is supplied from the power supply 5 to a load 6. By separating the contact 2 from the contact 1, current supply to the load is shut off. Since no current is supplied to the contacts 1 and 2, no arc is generated between the contacts, thus being explosion-proof and preventing electrical shock accident from occurring. With this configuration, a low-cost, simple-construction, explosion-proof, and highly safe connector can be obtained and a connector which can be used even at a highly humid location or within conduction liquid can be obtained.

Description

DETAILED DESCRIPTION OF THE INVENTION [Industrial Field of Application] The present invention is applicable to coal mines where flammable gases or vapors of combustible liquids are or sometimes are present, where explosive dust is present. When connecting an electrical device to a power source in a location where live parts are undesirable to be exposed (for example, underwater, outdoors where it may be exposed to rainwater, or in a humid location even indoors), take precautions to prevent electric shock. Non-current-carrying contacts are suitable where electrical appliances are required to have a reduced voltage, or where it is necessary to reduce the voltage applied to appliances in order to reduce the size of the appliance to save storage space (and reduce costs). This invention relates to an electrical connector with a child.

[Prior Art] Generally, as an electrical connector used to connect electrical equipment to a power source, a plug connector consisting of an outlet and a plug is used. This type of connector cannot be used as is in an atmosphere containing flammable gas or explosive dust because an arc is generated when the plug is removed from the outlet while the connector is energized.

Therefore, when using conventional electrical connectors in these atmospheres, special structures such as a built-in interlock switch that allows the plug to be inserted or removed only when the switch is open are required. It was necessary to hire.

In addition, with commonly used plug-in connectors, the contacts of the outlet connected to the power source are exposed when the plug is removed, so if the outlet is left connected to the power source underwater. A short circuit occurs between the contacts of an outlet through water, causing an electrical leak, which can sometimes cause electric shocks to people and animals. Furthermore, if water enters between the plug contact and the contact of the outlet after the plug is connected to the outlet, the insulation will deteriorate.

Therefore, as seen in Japanese Patent Application Laid-open No. 63-6762, a cavity is provided in the outlet to contain an insulating liquid, and the contact of the outlet is placed inside the cavity, so that when the plug is unplugged from the outlet, A connector has been proposed in which the socket is filled with an insulating liquid and the insulating liquid insulates the contacts of the outlet.

Conventionally, when it is particularly necessary to improve the safety of electrical equipment to prevent electric shock accidents, an isolation transformer is installed to step down the voltage obtained from the commercial power supply, and the secondary side of the isolation transformer is One method is to drive the load with a low voltage that can be obtained.

[Problem to be solved by the invention] In order to make conventional electrical connectors explosion-proof, it is necessary to adopt a special structure such as incorporating a switch, which inevitably makes the structure complicated. Ta.

Furthermore, in order to be used underwater, conventional electrical connectors use insulating liquid to insulate the contacts of the outlet.
Since it is necessary to fix the outlet in a certain direction to prevent the insulating liquid from escaping, it is only applicable when the outlet is fixed in a certain position underwater, and it is not possible to attach the outlet underwater. It could not be used when there is a risk that the posture of the person may change at any time.

Furthermore, if a conventional electrical connector is connected or disconnected in the rain, or if it is handled in a building that handles water or is humid, water droplets may get inside the connector. Not only is there a risk of electrical leakage if moisture condenses, but there is also a risk of electric shock if you touch it with your hands.

Conventionally, connectors with waterproof caps have been used in places where electrical leakage accidents may occur, but there is a problem in that attaching the waterproof caps makes attaching and detaching the connectors troublesome.

Furthermore, if a step-down isolation transformer is installed when it is required to increase the safety of electrical equipment, not only will the equipment become larger and heavier, but the primary side of the isolation transformer, which requires special attention to safety, will be mixed. There was a problem.

One object of the present invention is to make it possible to freely connect and disconnect energized circuits by connecting and disconnecting contacts that are not energized, thereby achieving explosion-proofness and water resistance with a simple structure. To provide an electrical connector with a non-energizing contact that can be held in place.

Another object of the present invention is to provide an electrical connector that can prevent live parts from being exposed, thereby increasing safety against electric shock accidents.

Still another object of the present invention is to provide a non-energized contact that can lower the voltage applied to electrical equipment without separately providing an isolation transformer, thereby increasing the safety of electrical equipment and power supply. Our goal is to provide electrical connectors with

[Means for Solving the Problems] An electrical connector according to the present invention includes a power supply side contact and a load side contact made of a ferromagnetic material, and a power supply side contact and a load side contact respectively wound on the power supply side contact and the load side contact. It includes a coil and a load side coil.

The power supply side contact and the load side contact have magnetic pole parts that can be freely connected and disconnected, and when the magnetic pole parts of both contacts are connected, both contacts connect the power supply side coil and the load side contact. A closed magnetic path is configured to flow a magnetic flux that interlinks with the load side coil.

The basic configuration of the present invention is as described above, but in practical use, the above-mentioned It is preferable to further provide an auxiliary contact that magnetically shorts between the magnetic pole parts of the power source contact when the load side contact is separated from the power source contact.

In addition, by providing a bypass magnetic path that bridges the magnetic pole parts of the power-side contacts, and by flowing magnetic flux through the bypass magnetic path when the load-side contact is disconnected from the power-side contact, the power-side coil is The excitation current that flows may be limited.

If the device is intended to be used underwater, it is preferable to cover the power supply side coil and the load side coil with an insulating exterior having a liquid-tight structure.

Furthermore, in order to reduce the voltage applied to electrical equipment and increase safety, the power supply coil and load coil should be connected so that the voltage obtained at the load coil is lower than the voltage applied to the power supply coil. It is also possible to set the turns ratio.

"Function" In the electrical connector described above, when the magnetic pole part of the load side contact is connected to the magnetic pole part of the power supply side contact, a closed magnetic path is formed by both contacts, so the power supply side coil and the load side coil are connected. Magnetically coupled. Therefore, when the power source side coil is connected to the power source, a voltage is induced in the load side coil, and energy is transferred from the power source to the load.

In the electrical connector of the present invention, since the power supply side contact and the load side contact that actually connect and disconnect are not energized, an arc occurs between both contacts even if both contacts are exposed. Never.

Therefore, the load can be connected and disconnected without arcing without adopting a special structure such as incorporating an interlock switch. Furthermore, since the basic structure of the present invention is simple, consisting of a contact made of a ferromagnetic material and a coil wound around it, it is easy to manufacture, and an explosion-proof connector can be provided at low cost.

In the electrical connector of the present invention, even if liquid such as water comes into contact with the power supply side contactor and the load side contactor, insulation problems will not occur. It is possible to obtain a connector that can be used in a conductive liquid. Moreover, if even the coil part is covered with an insulating exterior, the live part will not be exposed, thereby eliminating the risk of electrical leakage caused by water or humidity.

Furthermore, since the electrical connector of the present invention does not have any part that restricts the posture during use, both the power supply side contact and the load side contact can be used in any posture when used underwater.

Furthermore, in the electrical connector of the present invention, since the live portion can be prevented from being exposed, safety against electric shock accidents can be improved.

In the electrical connector of the present invention, when the turns ratio of the power supply side coil and the load side coil is set so that the voltage obtained at the load side coil is lower than the voltage applied to the power supply side coil, voltage can be lower than that of the commercial power supply. Therefore, the voltage applied to electrical equipment can be lowered, the insulation structure of electrical equipment can be simplified, and step-down isolation transformers are no longer required. Together with this, the space required for the equipment becomes smaller, and the cost of the equipment can be reduced.

In the present invention, an isolation transformer is configured by the power supply side contact, the load side contact, the power supply side coil, and the load side coil. ) should have a size commensurate with that. Therefore, the cost required to implement the present invention is lower than that required when an isolation transformer with a large capacity is separately installed in order to drive a large number of loads.

[Example] The present invention will be described in detail below with reference to the accompanying drawings.

FIG. 1 shows the basic configuration of an embodiment of the present invention. In the figure, 1 and 2 are power supply side contacts and load side contacts made of ferromagnetic materials such as iron, and 3 and 4 are These are a power supply side coil and a load side coil, respectively. The power supply side coil 3 and the load side coil 4 are respectively wound around the power supply side contactor 1 and the load side contactor 2 in a state in which they are insulated from the solid contacts.

In order to reduce loss, in the frequency range close to the commercial frequency, it is desirable that the power supply side contact 1 and the load side contact 2 be constructed of a laminate of electrical steel sheets such as silicon steel plates, and in the frequency range of IKHz or higher, the power supply side contact 1 and the load side contact 2 are It is desirable that the contact 1 and the load-side contact 2 be made of permalloy or the like.

In this embodiment, power supply side and load side contacts 1 and 2 are each formed in a U-shape, and power supply side magnetic pole parts 1a and lb are provided at both ends of the power supply side contact 1, and load side contact 2 is provided with power supply side magnetic pole parts 1a and lb. Power supply side magnetic pole portions 1a are provided at both ends.

Load-side magnetic pole portions 2a and 2b corresponding to lb are formed, respectively.

Power supply side magnetic pole parts 1a, lb and load side magnetic pole part 2a.

2b are constructed so that they can be freely connected and disconnected from each other, and the magnetic pole parts 1a and 2a of the fixed contacts 1 and 2 and 1b,
When the coils 2b are connected to each other, a closed magnetic path is constructed in which a magnetic flux interlinking with the power source coil 3 and the load coil 4 flows through the fixed contacts.

The power supply side magnetic pole part and the load side magnetic pole part may be connected by simply butting them together (in this case, other means for maintaining the contactor 1.2 in the connected state is essential). ), or both magnetic pole parts may be connected in a fitting structure. If both magnetic pole parts are connected in a fitting structure, some of the steel plates will overlap at the connection part, so the magnetic resistance at the connection part can be reduced.

In the illustrated example, recesses la1.
lbl is provided, and convex portions 2a are provided on the load side magnetic pole portions 2a, 2b.
1. 2bl are provided, and the convex portions 2a1. 2bl is fitted into the recesses 1al and 1bl of the power supply side magnetic pole parts 1a and 1b, thereby connecting both magnetic pole parts.

In this embodiment, opposing protrusions IC and 1d are provided on the inside near both ends of the power supply side contactor 1, and recesses 1cl and ldl are provided in these protrusions IC and 1d, respectively. These projections 1c.

1d, as shown in FIG.
used to connect. In this example, the auxiliary contact 9 is made of a single-shaped iron core made of magnetic material, and the convex portions 9a and 9b provided at both ends are the concave portions 1cl and 1.
c2 is connected between the power supply side magnetic pole parts 1a and lb of the power supply side contact 1.

Both ends 3a and 3b of the power source coil 3 are connected to an AC power source 5 through an electric cord, either directly or via a switch (not shown). Further, a load 6 is connected between both ends 4a and 4b of the load side coil 4.

It is preferable that the power supply side coil 3 and the load side coil 4 be covered with water-resistant insulating sheaths 7 and 8. This insulating exterior can be formed by resin molding.

In the above embodiment, when the power source side coil 3 is connected to the power source 5 and the magnetic pole part of the load side contactor 2 is connected to the magnetic pole part of the power source side contactor 1, a closed magnetic path is formed by the fixed contact. The power supply side coil 3 and the load side coil 4 are magnetically coupled. Therefore, a voltage is induced in the load-side coil 4, and energy is supplied from the power source 5 to the load 6. Further, when the load side contactor 2 is separated from the power supply side contactor 1, the magnetic coupling between the power supply side coil and the load side coil is eliminated, so that the power supply to the load can be cut off.

The electrical connector according to the present invention can be used for applications requiring explosion-proof properties,
It is effective in all kinds of applications, including applications that require water resistance and applications that prevent electric shock accidents for children.

That is, in the electrical connector of the present invention, the power supply side contact 1 and the load side contact 2, which are actually connected and disconnected.
Since there is no current flowing through the terminal, no arc will occur between the two liquid contactors even if both liquid contactors are exposed. Therefore, even when the power source side coil 3 remains connected to the power source 5, the load can be connected and disconnected without arcing, and explosion-proof properties can be provided.

Further, in the electrical connector of the present invention, since the live portion is not exposed, electric shock accidents can be prevented.

Furthermore, since the power supply side contact 1 and the load side contact 2 do not cause insulation problems even if they come into contact with liquid such as water, it is necessary to make them water resistant by simply covering at least the coil portion with a water resistant insulating exterior. This makes it possible to obtain an electrical connector that is free from the risk of electrical leakage caused by water or moisture. Furthermore, by covering the coil portion with a water-resistant insulating sheath, it is possible to obtain an electrical connector that can be used in conductive liquids such as water and seawater.

When designing the above-mentioned electrical connector, first determine the electrical capacity according to the load, and then determine dimensions such as the cross-sectional area of each contact and the length of the legs. Once the core structure of each contact is determined in this manner, the voltage per turn of the power supply coil is determined. Next, the number of turns of the power supply side coil is determined according to the voltage of the connected power supply, and the number of turns of the load side coil is appropriately set according to the voltage of the load side.

In the above embodiment, when the load side contact 2 is disconnected from the state shown in FIG. 1, the impedance of the power source coil 3 decreases, and the excitation current flowing through the power source coil 3 increases. In order to suppress this excitation current, the magnetic pole portion la of the power supply side contactor 1.

What is necessary is to magnetically short-circuit between 1b and then disconnect the load-side contactor. That is, before disconnecting the load side contactor 2, as shown in FIG. 2, the recess 1c1.
ldl is the magnetic pole part 9a of the auxiliary contactor 9.

By fitting 9b, the magnetic pole parts 1a and lb are magnetically short-circuited to form a closed magnetic path with the auxiliary contact 9 and the power supply contact 1, and then the load contact 2 is disconnected. Bye.

In addition, in order to prevent excessive excitation current from flowing to the power supply coil when the load side contactor 2 is disconnected, when the load side contactor 2 is disconnected and the impedance of the power supply side coil 3 decreases, A circuit that detects and cuts off the power,
It may also be provided between the power source and the power source coil.

FIG. 3 shows an example of the configuration of such a circuit. In this example, a relay 11 is connected in parallel to the power supply coil 3, and the relay 11 is normally connected between the power supply 5 and the power supply coil 3. An open contact 11a is connected, and a current limiting resistor 12 is connected in parallel to the contact 11a.

In the circuit shown in FIG. 3, when the load contact 2 is connected to the power supply contact 1, the impedance of the power supply coil 3 is high, and the voltage across it reaches the voltage that operates the relay 11. Therefore, the contact 11a is closed.

Therefore, the current is passed from the power supply 5 to the power supply coil 3 at the contact 11a.
It is done through. When the load-side contact 2 is disconnected from the power-side contact 1, the impedance of the power-side coil 3 decreases, so the voltage across it decreases, the operation of the relay 11 stops, and the contact 11a opens. Therefore, current is passed from the power source 5 to the power source coil 3 through the current limiting resistor 12, and the current flowing through the power source coil 3 is limited. When the load-side contact 2 is connected to the power-side contact 1, the impedance of the power-side coil 3 increases, the voltage across it increases, and the relay 11 operates, so the contact 11a automatically closes. Electricity is supplied from the power supply to the power supply side coil without any problem.

In addition, instead of using a contact relay as shown in Fig. 3, the same effect as described above can be obtained by using a non-contact switch such as a transistor or thyristor and controlling the switch according to the voltage across the power supply side coil 3. A circuit with functions can be constructed.

4 and 5 show another embodiment of the present invention. In this embodiment, the power supply side contactor 1 has a magnetic pole portion 1a.
, lb is provided with a bypass magnetic path IA bridging between them.

Further, the power supply side contactor 1 and the power supply side coil 3 are embedded in an insulating device 2 formed by resin molding.

The insulating device 2 has a hole 12a that opens toward the load side contactor 2 side.
, 12b are provided, and magnetic pole parts 1a, lb are provided in these holes.
is located.

The magnetic pole parts 1a, lb are provided with holes 1e, if that communicate with the deepest parts of their recesses, and these holes le, If are connected to the outside through communication holes 12c and 12d provided through the insulating device 2. is communicated with.

Furthermore, a portion of the load side contactor 2 excluding the vicinity of the magnetic pole parts 2a and 2b and the load side coil 4 are buried in an insulating device 3 formed by resin molding similarly to the insulating device 2 described above. As shown in Fig. 5, the magnetic pole part 2a of the load side contactor 2,
2b are connected to the magnetic pole parts 1a, lb through the holes 12a, 12b of the insulating device 2.

A pair of locking claws 12e and 12f are provided on both side surfaces of the end of the insulating device 2 on the load side contact side. Furthermore, locking claws 12e are provided on both sides of the insulating device 3.

Arm portions 13a and 13b are provided corresponding to the arm portions 12f, respectively, and protrusions 13c and 13d are provided at the tips of the arm portions 13a and 13b. Each of the locking claws 12e and 12f has a hook-shaped tip, and the locking claws 12e and 12f each have a hook-shaped tip.
a, 2b are connected to the magnetic pole parts la, lb of the power supply side contactor 1 through the holes 12a, 12b, respectively, the locking claw 12e
, 12f elastically engage with the protrusions 13c and 13d, respectively, to connect the insulating devices 2 and 13. Also, push the arm portions 13a, 13b to remove the protrusions 13c, 13.
Insulating device 3 is removed from insulating device 2 while retracting d inward.
By pulling the protrusions 13c and 13d away from the locking claws 12e and 12f, the load side contact 2 can be easily separated from the power supply side contact 1.

As described above, when the bypass magnetic path IA is provided in the power source side iron core 1, when the load side contact 2 is separated from the power source side contact 1, a closed magnetic path is formed in the power source side contact 1.
It is possible to prevent the impedance of the power source coil 3 from decreasing, and it is possible to suppress the excitation current.

When the load side contact 2 is connected to the power supply side contact 1,
Most of the magnetic flux flows through the closed magnetic path formed by contacts 1 and 2, and almost no magnetic flux flows through the bypass magnetic path IA, so there is no practical problem even if the bypass magnetic path is provided as described above. .

With the above configuration, the power supply side contact 1 and the load side contact 2 can be firmly connected by the engagement between the locking claws 12e, 12f and the protrusions 13c, 13d, and the solid contact can be prevented by external force. This will prevent it from being easily separated. In this case, the magnetic pole parts 1a and Lb of the contact 1 and the magnetic pole part 2a of the contact 2.

The connection with 2b can also be a simple butt connection.

In addition, as described above, inside the holes 12a, 12b and the magnetic pole part 1a,
Communication holes 12c and 12d that communicate the inside of the recess of lb to the outside
If the hole 12a is provided, the hole 12a can be opened when connecting the load side contact 2 to the power supply side contact 1 underwater.

Since the water in 12b can be removed through the communication holes 12c and 12d, the contacts can be easily connected.

Similarly, when connecting the load side contact 2 to the power supply side contact 1 in dusty conditions, the dust that has entered the holes 12a and 12b can be removed through the communication holes 12c and 12d, making it easy to connect the contacts. can be made to do so.

In each of the above embodiments, a single-phase connector is shown, but a three-phase connector can also be constructed as shown in FIG. 6. In the example shown in FIG. 6, the magnetic pole parts 1u, 1v and I
Three-phase power supply side coils 3u, 3v, and 3W are wound around the 8-shaped power supply side contact 1- having a W, and magnetic pole parts 2u, 2v are wound.
In this case, the load side coils 4u, 4v and 4w are wound around the 8-shaped load side contactor 2' having 2W and 2W.
Although various coil connections are possible, in the illustrated example, the power supply side coils 3u to 3w are star connected, and their U-W three phase terminals and neutral point terminals Ul, Vl, Wl, and N are drawn out. Further, the load side coils 4u to 4w are connected in delta, and three-phase terminals U2゜2 and W2 are drawn out.

In addition, in this example, the magnetic pole parts 1u, 1w of the power supply side contactor 1-
Bypass magnetic paths IA1 and IA2 are provided to bridge between the magnetic pole parts 1v and 1w, respectively, and these bypass magnetic paths allow the load-side contact 2- to connect to the power-side contact 1'
The excitation current that flows through the power supply side coils 3u to 3w when the coils are disconnected from the power supply side coils 3u to 3w is suppressed.

In each of the above embodiments, if the turns ratio of the power supply side coil and the load side coil is set so that the voltage obtained at the load side coil 4 is lower than the voltage applied to the power supply side coil 3, the load Since the applied voltage can be lower than the power supply voltage, the load can be driven with a low voltage and safety can be improved without the need to install a separate step-down isolation transformer. Since the safety standards required for the system can be lowered, the cost can be reduced.

Furthermore, by preparing many types of load side contacts with different numbers of turns of the load side coils, one power source side contactor can be used in common for a plurality of loads having different voltages.

[Effects of the Invention] As described above, according to the present invention, the power supply side coil and the load side coil are respectively wound around the power supply side contactor and the load side contactor made of ferromagnetic material, and the solid contactor is connected. Since the power supply and the load can be connected and disconnected by disconnecting the power supply and the load, the load can be connected and disconnected without generating an arc. It has the advantage of being much simpler in structure and explosion-proof than other electrical connectors.

Furthermore, since the live parts are not exposed, electric shock accidents can be prevented in all applications.

Furthermore, the power supply side contact and the load side contact do not cause insulation problems even if they come into contact with liquids such as water, so at least the coil part can be made water resistant by simply covering it with an insulating sheath, making it suitable for use outdoors or outdoors. Electrical connectors used in humid locations,
Electrical connectors for use in conductive liquids can be easily obtained.

Further, according to the present invention, since there is no part that restricts the posture during use, there is an advantage that both the power supply side contact and the load side contact can be used in any posture even when used underwater.

In particular, according to the invention set forth in claim 5, the turns ratio between the power supply side coil and the load side coil is set so that the voltage obtained at the load side coil is lower than the voltage applied to the power supply side coil. This has the advantage of being able to supply a voltage lower than the power supply voltage to the load without installing a separate step-down isolation transformer, and improving the safety of the load at low cost.

[Brief explanation of drawings]

FIG. 1 is a configuration diagram showing an embodiment of the present invention, FIG. 2 is a configuration diagram showing a state in which an auxiliary contact is connected to the power supply side contact of the embodiment of FIG. 1, and FIG. 3 is a configuration diagram of the embodiment of FIG. FIGS. 4 and 5 are circuit diagrams showing the configuration of a circuit suitable for limiting the excitation current when using the connector of the embodiment, and FIGS. 4 and 5 show other embodiments of the present invention. 5 is a cross-sectional view showing the connector of the same embodiment in a disconnected state, FIG. 5 is a cross-sectional view showing the connector in a connected state, and FIG. 6 is a configuration diagram showing still another embodiment of the present invention. 1...Power supply side contacts, la, lb, lu to 1w. ...Magnetic pole part, IA...Bypass magnetic path, 2...Load side contactor, 2a, 2b, 2u-2w...Magnetic pole part, 3.
...Power side coil, 4...Load side coil, 5...Power supply, 6...Load, 9...Auxiliary core.

Claims (5)

[Claims] (1) A power supply side contact and a load side contact made of a ferromagnetic material, and a power supply side coil and a load side coil respectively wound around the power supply side contact and the load side contact, and the power supply side contact. The child and the load-side contact have magnetic pole parts that can be freely connected and disconnected, and when the magnetic pole parts of both contacts are connected, the power-side coil and the load-side coil are connected to each other by both contacts. An electrical connector with a non-energizing contact characterized by comprising a closed magnetic path through which interlinking magnetic fluxes flow. (2) The non-energized device according to claim 1, further comprising an auxiliary contact that magnetically shorts between the magnetic pole parts of the power source contact when the load side contact is separated from the power source contact. Electrical connector with contacts. (3) The electrical connector with a non-current contact according to claim 1, wherein the power supply side contact has a bypass magnetic path bridging between its magnetic pole parts. (4) Claim 1 characterized in that the power supply side coil and the load side coil are covered with an insulating exterior having a liquid-tight structure.
The electrical connector with a non-current contact according to any one of 3 to 3. (5) A turn ratio between the power supply side coil and the load side coil is set so that the voltage obtained at the load side coil is lower than the voltage applied to the power supply side coil. 5. The electrical connector with a non-current contact according to any one of items 4 to 4.