JPS6222978Y2 - - Google Patents

Description

[Detailed Description of the Invention] This invention relates to a limit switch device that is often used in shutters, and more particularly, to a limit switch device that is useful for protecting a curtain drive mechanism.

Electric shutters that use motor power to extend or wind the curtains are equipped with a limit switch in the motor's power supply circuit, and when the shutters are opened (or closed), the curtains are closed. An upper switch (or lower switch) is activated when the vehicle reaches the top (or bottom), and this switch stops the motor to prevent excessive force from being applied to the motor and transmission system.

Here, there are two methods for forming this type of limit switch device: a direct method in which the switch is actuated directly by the curtain being lifted and lowered, and a sensor for the curtain lifting and lowering stroke is attached in the middle of the drive train transmission mechanism. An indirect type switch device is known in which the switch is actuated at both ends of the stroke, and the present invention is directed to the latter type of indirect type switch device.

However, in the general stroke sensor used in conventional indirect switch devices, a large nut-shaped moving piece is screwed into a screw rod that rotates forward and backward in conjunction with the opening and closing movements of the curtain. The piece is engaged with a stationary part so that the switch is actuated by the movement of the moving piece.

Furthermore, among the structures with screw rods, there are two types: one-shaft type and two-shaft type.
There is a shaft type, and each type has the following special disadvantages.

(a) Single-axis type A moving piece for opening upper limit operation (hereinafter referred to as piece A) and a moving piece for closing lower limit operation (hereinafter referred to as piece B)
Although this structure has the advantage of making the structure more compact, it is troublesome to adjust the stroke position of the moving piece AB, and the adjustment operation is difficult. The disadvantage is that it lacks reliability.

(b) Two-axis type A structure in which two simultaneous rotation screw rods are mounted side by side, and piece A and piece B are fitted into separate screw rods.In this configuration, the adjustment of moving piece AB, While this has the advantage of making adjustment operations easier and more reliable,
The disadvantage is that the structure is large.

The present invention was devised to eliminate the above-mentioned drawbacks of the single-axis type configuration.In other words, the purpose of the present invention is to provide a compact structure with excellent adjustability, stability, and reliability of the moving piece. An object of the present invention is to provide a limit switch device for a shutter.

Hereinafter, the present invention will be explained based on an illustrated embodiment.

As shown in FIG. 1 (reference numeral 1), the switch device of the embodiment is placed alongside a reduction gear 3 connected to the output side of a shutter motor 2, and the passive gear 4 of the switch device 1 is It is connected to the gear 7 of the output shaft 6 of the speed reducer 3 via the idler 5.

A chain 12 is wound between the output sprocket 8 of the output shaft 6 and the sprocket 11 attached to the shaft 10 of the curtain hoisting drum 9, and the hoisting drum 9 is fed out by the motor 2. , the winding is driven.

By the way, as shown in FIGS. 2 to 5, the switch device 1 is assembled to a board 12 and side plates 13 erected at both ends of the board 12.
A screw rod 14 with a passive gear 4 attached to its tip is supported by both side plates 13, and an upper switch 16 and a lower switch 17 are attached with screws to the left and right sides of the board 12 via brackets 15. It is being

Note that each switch 16, 17 is provided with a terminal plate 16a, 17a and an operating arm 18, 19.

Next, each of the pieces A20 and B21 screwed into the screw rod 14 is a member in which a round nut part 22 and a boss part 23 are integrally formed, as shown in FIG. On the end face of the nut part 22,
A knurled surface 22a is formed, and an interlocking tooth row 22b is formed on the back surface of the nut portion 22, and a snap groove 23a is formed near the end of the boss portion 23.

Therefore, in the boss portion 23 of each piece 20, 21,
An arch-shaped slider 24 is slidably fitted on the bottom surface 2 of the plank forming the lower half of the slider 24.
4a is in sliding contact with the upper surface of the base plate 12, and a meshing tooth row 24b that meshes with the tooth row 22b is formed on the annular surface of the slider 24 that is in contact with the round nut portion 22.

The snap ring 25 fitted in the snap groove 23a prevents the spring washer 26 from coming out, and a compression spring 27 is interposed between the washer 26 and the slider 24, so that the spring washer 26 is not removed.
is pressed against each piece 20, 21, whereby rotation is prevented between the pieces 20, 21 and each slider 24 via meshing tooth rows 22b, 24b.

In addition, each part mechanism mentioned above is the base plate 12 and the side plate 1.
It is protected from dust by a cover (not shown) placed over 3.

Next, the assembly and operation of the switch device 1 thus constructed will be described.

Since both the curtain winding drum 9 and the screw rod 14 are driven by the output shaft 6, the screw rod 14
rotates forward and backward in conjunction with the opening/closing movement of the curtain, and each piece 20, 21 is fixed to the base plate 12 via each slider 24, so each piece 20, 21 rotates forward and backward in conjunction with the opening/closing movement of the curtain. It reciprocates on the screw rod 14 in response to the opening and closing movements of the screw rod 14.

Therefore, the opening (or closing) movement of the curtains
In this case, the pieces 20 and 21 advance to the left (or right) in the drawing, and in the open state shown in which the curtain is completely raised, the piece A20 presses down the roller 18a of the actuating arm 18 of the upper switch 16 with the knurled surface 22a. As a result, the power supply to the motor 2 is stopped and the curtain stands still.

On the other hand, when the curtain is lowered by closing the shutter, the pieces 20 and 21 move to the right from the position shown in the figure.
Furthermore, when the curtain is completely lowered, the knurled surface 22a of the piece 21 presses down the roller 19a,
The lower switch 17 is operated and the curtain is similarly stopped at the closed position.

In this way, since the drive of the curtain is automatically stopped at the open/closed position, no excessive force is applied to the shutter motor 2 and its transmission mechanism.

By the way, when the shutter is placed on site, or when the transmission mechanism is reassembled for repairs, etc., it is necessary to adjust the stroke position of the pieces 20 and 21 to match the opening/closing degree of the curtain. To do this, it is necessary to temporarily release the locks on the pieces 20 and 21 and move the pieces 20 and 21 to the operating positions of the switches 16 and 17 while the screw rod 14 stops rotating.

Therefore, in order to adjust the pieces 20, 21 with the above structure, the slider 24 is separated from the pieces 20, 21 against the elasticity of the spring 27, and the tooth rows 22b, 24 are moved away from the pieces 20, 21.
Once the engagement between the pieces 20 and 21 is released, the pieces 20 and 21 can be rotated freely, so the operation is extremely easy.Furthermore, when the operation is stopped, the slider 24 moves the pieces 20 and 20 with a strong spring force. , 21, so there is no possibility of deviations in adjustment caused by external environmental forces such as shutter vibrations, which eliminates the uncertainty and instability of stroke adjustment, which was a drawback of the conventional single-shaft type. has been done.

In addition, in the configuration of the above embodiment, the switch is operated at both extreme strokes of fully opening and fully closing the curtain, but if the number of movable pieces and switches is increased, the degree of fully opening and fully closing can be increased. In addition, the curtain drive can be stopped in the same way at intermediate opening degrees.

As described above, according to the limit switch device for a shutter according to the present invention, the movable piece is prevented from rotating by the immovable part via the coaxial slider that is freely engageable and detachable, and the slider is moved from the movable piece by pressing the spring member. Even with a compact structure, it is possible to easily and reliably adjust the stroke position of the moving piece. This has the effect of improving the practicality and reliability of the limit switch device.

In addition, in order to adjust the stroke movement position of the movable pieces 20, 21 that actuate the switches 16, 17, the slider 24 is moved in the axial direction against the pressure of the spring 27 to separate the meshing tooth rows 22b, 24b. After that, if the movable pieces 20 and 21 on the screw rod 14 are turned as desired and then the slider 24 is released, the slider 24 is moved again by the spring 27.
0, 21 and opposing meshing tooth rows 22
b and 24b naturally engage with each other, and the above adjustment is completed.

Therefore, according to the present invention, the above-mentioned adjustment work is extremely easy with one touch, and there is no possibility that the adjustment position may shift during operation due to the elastic engagement of the opposing meshing tooth rows 22b and 24b by the coil spring 27. In addition, there is no interlocking tooth row 22b,
24b is molded on the contact surface and can be engaged by shifting the engagement position by small pitches, which has excellent practical effects such as fine adjustment.

Furthermore, since the coil spring 27 is interposed concentrically with the facing meshing tooth rows 22b and 24b and presses the meshing tooth rows evenly, the engagement between the tooth rows is also strong and during operation. There is no risk of the adjustment position shifting.

[Brief explanation of the drawing]

FIG. 1 is an equipment diagram of a shutter limit switch device showing an embodiment of the present invention, and FIG.
The same plan view, Figure 3 is the same side view, and Figure 4 is the same side view.
A front cross-sectional view taken along the - line in the figure, FIG.
FIG. 5 is a perspective view of the moving piece and slider shown in FIGS. 1... Switch device, 2... Motor, 14...
Screw, 16, 17... Switch, 18, 19...
Operating arm, 20, 21... Moving piece, 22... Round nut portion, 22b, 24b... Interlocking tooth row, 23...
...Boss part, 24...Slider, 24a...Bottom surface,
27... Spring as a spring member.

Claims (1)

[Scope of utility model registration request] A plurality of movable pieces 20 and 21 are externally engaged with a screw rod 14 that rotates forward and backward in conjunction with the opening/closing movement of the curtain, and the movable pieces are engaged with an immovable portion in a non-rotatable manner. By fixedly disposing a plurality of switches 16 and 17 of the same number with the ends of their actuating arms facing the path of the shutter motor, each switch independently energizing the shutter motor. A limit switch device for a shutter that selectively operates the switch depending on the degree of opening and closing includes a round nut-shaped moving piece 20 with a longitudinal boss 23 extending out;
21, and an arched slider 24 slidably fitted onto the boss 23, the flat bottom surface 24a
The slider 24 is brought into sliding contact with the immovable surface, the meshing tooth rows 22b, 24b formed on the contact annular surfaces of the movable pieces 20, 21 and the slider 24, and the slider 24 is brought into sliding contact with the movable pieces 20, 21. A coil spring member 27 is provided which is a spring member 27 that presses and urges the ring surface and is wound along the outer periphery of the boss 23 between the ring 25 on the outer periphery of the tip of the boss 23 of the moving piece and the slider 24. A shutter limit switch device characterized by: