JPS6222025Y2 - - Google Patents

Description

[Detailed Description of the Invention] This invention relates to a structure in which an operation indicator lamp for confirming the operation of a limit switch is attached to the limit switch.

As is well known, some limit switches are equipped with an operation indicator lamp to conveniently check the operating status during maintenance and inspection. Conventional limit switches of this type with an operation display have a display mechanism pre-built into the switch body,
Since the display mechanism is pre-integrated between the switch body and the terminal protection cover using a resin mold, it is considerably more expensive than a normal limit switch that does not have an operation display. Furthermore, in the past, it has not been possible to change a normal limit switch without an operation display to an operation display type as needed.

This idea was made in view of the above points, and a terminal protection cover that is detachably attached to the limit switch so as to cover the terminal wiring section is provided with a lamp unit that is configured to be detachable. By connecting the terminals to the terminals of the limit switch inside the cover, an operation indicator lamp mounting structure is provided that allows a limit switch with an operation indicator to be constructed as required, as if it were integrated.

Hereinafter, embodiments of this invention will be described in detail based on the drawings.

In Fig. 1, 1 is a normal limit switch, 2 is a hinge lever type actuator,
COM, NO, and NC are the common, normally open, and normally closed screw terminals located on the bottom of the main unit, respectively.

Reference numeral 3 denotes a terminal protection cover which is detachably attached to the bottom surface of the limit switch 1 and covers the terminal wiring section, and FIG. 2 is a front sectional view thereof. This cover 3 is a molded article of synthetic resin, and has a general shape like a bottomed container with a completely open top.
Two communication holes 4, 4 are formed on both sides of the cover 3 to communicate the inside and outside of the cover, and cylindrical flanges 6, 6 surrounding the communication holes 4, 4 are formed on the outside of both sides. It is formed. Further, mounting claw pieces 8, 8 are formed extending upward from both side surfaces of the cover 3, and locking protrusions 9, 9 are formed on the inside tips of these claw pieces 8, 8.

The mounting claw pieces 8, 8 and the locking protrusions 9, 9 of the cover 3 fit into the cover mounting grooves 10, 10 provided on both sides of the main body case of the limit switch 1.
When the top open side of the cover 3 is aligned with the bottom terminal side of the limit switch 1 and pressed to join them together, the mounting claws 8, 8 will move laterally due to their elasticity. It enters the mounting grooves 10, 10 while being bent, and when the locking protrusions 9, 9 pass the step of the grooves 10, 10, the claw pieces 8, 8 elastically return, and the claw pieces 8, 8 and the protrusions 9, 9 Groove 1
0,10 will fit correctly. This allows the cover 3 to be attached to the limit switch 1.
Further, if the cover 3 and the limit switch 1 are strongly pulled in the direction of separation, the cover 3 can be removed from the limit switch 1 due to the elastic deformation of the claw pieces 8, 8.

Further, in FIG. 1, reference numeral 11 denotes a lamp unit that is detachably attached to the communication hole 4 and flange 6 of the cover 3, and FIG. 3 is a front sectional view thereof. As shown in FIG. 5, the lamp unit 11 includes neon lamps N connected in series, a cylindrical lamp body 12 with a built-in resistor R, and a rubber cap 13 attached to the cover 3 so as to enclose the lamp body 12. It consists of In addition, the lamp body 1
From one end of 2, connect two lead wires 1 of appropriate length.
4 and 14 are pulled out, and a crimp terminal 1 is attached to the tip.
5,15 are taken.

The rubber cap 13 is made of highly elastic rubber and has a thick rectangular cylindrical shape, and the cylindrical portion 16 on the tip side has a relatively small diameter and is adapted to elastically press-fit into the lamp body 12. Also, on the base end side, there is a large diameter groove 17 that elastically fits into the flange 6 of the cover 3.
is formed.

In the above configuration, as shown in FIG. 4, the lead wire 14 of the lamp unit 11 is passed through the communication hole 4 on one side of the terminal protection cover 3, and the flange 6 is elastically inserted into the large diameter groove 17 of the rubber cap 13 of the lamp unit 11. The lamp unit 11 is attached to the cover 3 by press-fitting. Also, first connect the wiring cable 18 to the rubber cap 1 of the lamp unit 11.
3, pass the tip of the wiring cable 18 through the other communicating hole 4 of the cover 3, and then attach the rubber cap 19 to the flange 6.
Press-fit into the Then, the lead wires 14, 14 and the wiring cable 18 guided inside the cover 3
are connected to the screw terminals COM, NO, and NC of the limit switch 1, for example, as shown in the wiring diagram of FIG. Thereafter, the terminal protection cover 3 is attached to the terminal wiring portion of the limit switch 1 in the manner described above. Then, it takes on the appearance of an integrated limit switch with an operation display, as shown in FIG. In the case of FIG. 5, when the switch 1 shown in the figure is not in operation, power is supplied to the load A, and no voltage is generated between the terminals COM and NC, so the neon lamp N does not light up. When the switch 1 operates and switches from this state, power is supplied to the load B, a voltage is generated between the terminals COM and NC, and the neon lamp N lights up.

By the way, the lamp body 12 is a rubber cap that is removably press-fitted into the flange 6 of the cover 3.
Rather than attaching it, simply prepare a rubber cap as a component to close the communication hole 4,
If the switch is not used as a limit switch with an operation display as shown in FIG. 4, the unnecessary communication hole 4 of the cover 3 may be closed with the rubber cap.

Note that Figures 6 and 7 show the terminal protection cover 3.
The cover 3 shown in Fig. 6 is an embodiment in which a communication hole 4 and a flange 6 are formed on the bottom side in addition to both sides, and Fig. 7 shows a cover 3 on the front side in addition to both sides. This is an example in which a communicating hole 4 and a flange 6 are also formed. The lamp unit 11 is installed in any arbitrary place of these communication holes 4, and the other arbitrary one is used as the outlet for the wiring cable 18, so that unnecessary communication holes 4
is closed with the rubber cap mentioned above.

As explained in detail above, according to the limit switch operation indicator lamp mounting structure of this invention, the user can easily replace a normal relatively inexpensive limit switch without an operation indicator with an operation indicator lamp as needed. Since it can be used as a limit switch, it is extremely convenient in practice.

[Brief explanation of the drawing]

FIG. 1 is a front view showing the limit switch, terminal protection cover, and lamp unit according to the present invention in a separated state, FIG. 2 is a front sectional view of the terminal protection cover, and FIG. 3 is a front sectional view of the lamp unit. Figure 4 is a front view of the combination of limit switch, terminal protection cover, lamp unit, and wiring cable, Figure 5 is a diagram showing an example of the connection between the switch and the lamp body, and Figure 6 is another example of the terminal protection cover. FIG. 7 is a front sectional view showing another example of the terminal protection cover. 1... Limit switch, 3... Terminal protection cover, 4... Communication hole, 6... Flange, 8... Mounting claw piece, 9... Locking protrusion, 10... Mounting groove, 1
1...Lamp unit, 12...Lamp body, 1
3...Rubber cap, 14...Lead wire, 18...
...Wiring cable.

Claims (1)

[Scope of utility model registration request] A terminal protection cover is removably attached to the limit switch so as to cover the terminal wiring section of the limit switch, and has at least two communication holes communicating between the inside and outside of the limit switch. The terminal of the lamp unit is connected to the terminal of the limit switch inside the terminal protection cover to serve as an operation indicator lamp for the limit switch, and the terminal of the lamp unit is connected to the terminal of the limit switch, which is connected to the terminal of the limit switch, and is connected to other terminals of the terminal protection cover. An operation indicator lamp mounting structure for a limit switch, characterized in that the hole serves as an outlet for a wiring cable of the limit switch.