JPS636836Y2 - - Google Patents

Description

[Detailed Description of the Invention] The present invention relates to an auxiliary contact unit that can be attached to a thermal overcurrent relay to add a contact circuit separate from the contact circuit built into the relay.

In general, thermal overcurrent relays transmit the amount of thermal curvature of a bimetal plate to an actuating plate via an interlocking plate, and the rotation of this actuating plate reverses the contact spring and drives the contacts in the reverse direction. , normally the contact is provided with only one circuit of C contacts. Therefore, when the switching signal of the overcurrent relay is extracted to a circuit other than the contact circuit, another electromagnetic relay is required in addition to the overcurrent relay, and the problem of installation space for the electromagnetic relay arises. In addition, when one circuit of A or B contacts is required in addition to the built-in C contact of the overcurrent relay, the smallest commercially available electromagnetic relay is a 4-circuit type, so the remaining three circuits are left idle and unused. There are also economic issues.

The purpose of the present invention is to solve these conventional problems and provide an auxiliary contact unit that can be added to an overcurrent relay to add contacts with a desired contact configuration without requiring an electromagnet. It is something to do.

Hereinafter, the present invention will be explained based on the embodiment shown in the drawings. Figures 1 to 4 show the configuration of an auxiliary contact unit for adding an A contact (1 circuit) to a thermal overcurrent relay. The unit case body 1 includes a connecting rod 2 that comes into contact with the contact spring when attached to the relay, a repulsion spring 3 that presses the connecting rod 2 against the contact spring with the minimum force, and a direction in which the connecting rod 2 moves. A movable contact 4 that moves integrally with the movable contact 4, movable contacts 5, 5 provided on this movable contact 4, fixed contacts 6, 6 that this movable contact 5 makes contact with and separate from, and this fixed contact 6.
The terminal fittings 7, 7 are provided with terminal screws 8, 8 for connecting external wiring to the terminal fittings 7, and the case body 1 is further provided with hooks 9, for detachably attaching them to the relay. 10 and 11 are arranged in series.

On the other hand, as shown in FIGS. 5 to 7, the relay 21 to which this unit is installed has an insertion hole 22 into which the connecting rod 2 of the unit is inserted so as to come into contact with the internal contact spring, and the hook portion 9. Engagement holes 23, 24, 25 with which 10, 11 are to be engaged are formed,
The unit is configured so that it can be installed with one touch. Note that 26 in the figure is a protective cover for the relay.

The state in which the above-described unit is attached to a relay is shown in FIGS. 8 to 10. In the figure, 27 is a bimetal plate, 28 is an interlocking plate that transmits the amount of thermal curvature of the bimetal plate 27 to the actuating plate 29, 30 is a contact spring that moves in reverse (snap action) when the actuating plate 29 rotates, and 31 is a contact spring. Fixed contacts shown.

Therefore, due to overcurrent, the bimetal plate 2 inside the relay
7 is bent and the actuating plate 29 is tilted to a certain angle or more, the contact spring 30 rolls, and the connecting rod 2 of the unit is pressed by the tip of the contact spring 30 and retreats inward of the unit case body 1. Enter. Therefore, the movable contacts 5, 5 come into contact with the fixed contacts 6, 6, and the circuit between the terminal screws 8, 8 is closed.

Note that the rear end of the connecting rod 2 is connected to the unit case body 1.
If it is made to enter and exit from the back side of the relay, it will be known that the overcurrent relay has operated when the rear end protrudes, and the function of indicating the operation of the relay can be provided.

FIG. 11 shows an embodiment in which the auxiliary contact unit has a b-contact configuration, where a indicates the non-operating state and b indicates the operating state. The numerals in the figure correspond to the respective numerals of the above-mentioned configurations, and are distinguished by adding ''.

As described above, according to the present invention, by attaching the auxiliary contact unit to the overcurrent relay, the opening and closing of the contacts in the unit can be mechanically linked to the reversing operation of the contact spring of the overcurrent relay. Compared to systems that use electromagnetic relays to obtain contacts, the problem of installation space can be solved, and the uneconomical effects of creating redundant circuits can also be eliminated.

[Brief explanation of drawings]

Fig. 1 is a front view showing an embodiment of the auxiliary contact unit according to the present invention, Fig. 2 is a side view thereof, Fig. 3 is a plan view thereof, and Fig. 4 is a sectional view taken along line A-A in Fig. 2. , FIG. 5 is a partially cutaway rear view showing the configuration of the overcurrent relay to which the auxiliary contact unit of the above embodiment can be attached, FIG. 6 is a side view thereof, FIG. 7 is a plan view thereof, and FIG. Partially cutaway rear view of the overcurrent relay with the auxiliary contact unit installed, Part 9
The figure is its side view, Figure 10 is its plan view, and Figure 11 is its side view.
The figure is a sectional view showing the configuration of an auxiliary contact unit having a b contact configuration. 1, 1': Unit case body, 2, 2': Connecting rod, 3, 3': Repulsion spring, 4, 4': Movable contact, 5, 5': Movable contact, 6, 6': Fixed contact,
7, 7': Terminal fitting, 8: Terminal screw, 9, 10,
11: Hook part, 21: Overcurrent relay, 22: Insertion hole, 23, 24, 25: Engagement hole, 26: Protective cover.

Claims (1)

[Scope of utility model registration request] An auxiliary device attached to a thermal overcurrent relay that transmits the amount of thermal curvature of a bimetal plate to an actuating plate via an interlocking plate, and the rotation of this actuating plate reverses the contact spring and drives the contacts in reverse. The contact unit has an engaging element that engages with an engaging part provided on the relay to attach the auxiliary contact unit to the relay, and has a fixed contact in the unit case and a movable contact that connects and separates from the fixed contact. 1. An auxiliary contact unit for a thermal overcurrent relay, comprising a contact and configured to transmit displacement due to reversal operation of a contact spring of the relay main body to a movable contact of the unit via a connecting rod.