JPS5850982Y2 - Band saw electric motor drive control device - Google Patents

Description

[Detailed Description of the Invention] The present invention relates to an electric motor drive control device for a band saw, and particularly to a band saw in which a band saw blade is suspended between a pair of saw wheels rotationally driven by an electric motor. The present invention relates to an electric motor drive control device suitable for stable and safe operation.

In a conventional bandsaw machine, a tensioning device for the band saw blade, a detection device for detecting the coming and going of the band saw blade, and a braking device for the saw wheel are each independent of each other.

However, if either the tension of the band saw blade or the tension of the band saw blade is inappropriate, the band saw machine cannot be operated stably and is dangerous to use.

Therefore, it is desirable to allow operation only when these conditions are appropriate, and to disable operation when these conditions become inappropriate.

Also, since the saw wheel has a large inertia, a braking device is required to stop it, but when it is operating, it is necessary to not supply power to the electric motor that is the rotational drive source of the saw wheel. It is.

The present invention was made in view of the above, and its purpose is to provide a band saw motor drive control device that allows stable and safe operation of the band saw. be.

The features of the present invention include a first detection means for detecting whether the tension level of the band saw blade is good or bad, a second detection means for detecting whether the band saw blade is moving in or out, and a braking device of the saw wheel. and third detection means for detecting the presence or absence of movement, the first detection means detects whether the tension is good, the second detection means detects whether the blade moves in or out, and the third detection means detects whether the tension is good. The present invention is characterized in that the electric motor that rotates the saw wheel can be driven only when no braking is detected.

The present invention will be explained in detail below using the embodiments shown in FIGS. 1 to 4.

Figure 1 is a front view of a band saw equipped with the device of the present invention;
The figure is a front view showing an embodiment of the entrance/exit detection means part for detecting the entrance/exit of the bandsaw blade of the apparatus of the present invention, and FIG. It is a front view showing an example.

In FIG. 1, reference numeral 1 denotes a support member. Two saw wheels 2 are rotatably supported on the support member 1, and a band saw blade 3 is stretched between the saw wheels 2.

The tension of the bandsaw blade 3 can be adjusted by operating the tensioning bundle 4, and in the present invention, the tension (tension degree) of the bandsaw blade 3 is detected by the detection means 5. The detection means 5 outputs a bi-level signal when the tension level is appropriate.

6 is a table. Further, the coming and going of the bandsaw blade 3 is detected by the coming and going detection means 7.

In FIG. 2, the roller 8 is rotatably supported by an arm 9, and the arm 9 is supported at a suitable position on the support member 1 so as to be rotatable around a shaft 10.

Therefore, the roller 8 is in contact with the back surface of the bandsaw blade 3 due to its own weight.

The above-mentioned entrance/exit detection means 7 is attached to the support member 1 so as to be able to detect a clockwise rotational change of the arm 9, and when the band saw blade 3 moves toward the front side of the main body, that is, to the left side in FIG. When the arm 9 rotates clockwise around the shaft 10 due to the weight of the roller 8, the entrance/exit detection means 7 operates and detects that the band saw blade 3 is moved further or further away from the regulation position. Inverts the output signal from bi level to low level.

In FIG. 1, 11 is a brake pedal, and 12 is a brake lining. As shown in FIG. 3, the brake lining 12 is provided at the tip of the brake pedal 11. 1
2 presses the inside of the saw wheel 2 to apply a brake to the saw wheel 2 which is rotating due to inertia.

By the way, in the present invention, this brake pedal 11
The detection means 13 detects whether or not the brake is operated (stepped on), and if it is not operated, the brake detection means 1
3 to output a bi-level signal.

Reference numeral 14 denotes an electric motor that rotates the saw wheel 2.

FIG. 4 is a block diagram showing one embodiment of the motor drive control circuit of the device of the present invention.

The saw wheel 2 is rotated by an electric motor 14, and in the present invention, the electric motor 14 is driven and controlled as follows.

In FIG. 4, 14 is an electric motor, and 15 is a starting switch for the electric motor 14. The starting switch 15 normally outputs a low level signal, and when operated, outputs a bilevel signal.

A stop switch 16 normally outputs a bi-level signal, and if operated by mistake, outputs a low-level signal.

17 is an AND gate, and the above-mentioned detection means 5, 7.13
It takes the output of , and outputs a bi-level signal when all inputs are bi-level signals.

18 is also an AND gate, which outputs a bi-level signal when both the output of the AND gate 17 and the output from the stop switch 16 are bi-level signals.

19 manually clears the output of the AND gate 18, and activates the start switch 15 only when the clear input is a bi-level signal.
This is a latch circuit in which the output signal of Q is latched by a rising signal that inverts from low level to bi level, and the Q output at that time is inverted from low level to bi level.

Further, this latch circuit 19 is activated when the clear input becomes low level, that is, when the stop switch 16 is operated, or when the output of any one of the detection means 5, 7.13 becomes low level. When this happens, the Q output is inverted from the bi level to the low level.

20 is a relay coil that is excited only when the Q output of the latch circuit 19 is a bi-level signal, and when the relay coil 20 is excited, its normally open relay contact 21 is closed;
The electric motor 14 rotates, the saw wheel 2 is rotationally driven via a belt, etc., and the bandsaw blade 3 starts running together with this.

As mentioned above (according to FIG. 4), when the band saw blade 3 is not in an appropriate tension state, when the band saw blade 3 moves out of the regulation position, or when the brake pedal 11 is depressed. When the electric motor 14
is not activated, and the bandsaw blade 3 does not travel.

Furthermore, when the band saw blade 3 is running and the brake pedal 11 is depressed, the output of the detection means 13 is reversed from the bi-level to the low level, so the human power to clear the latch rotation 19 becomes low level, and the latch Times lol! The Q output of r19 becomes low level, the excitation of the relay coil 20 is stopped, the normally closed relay contact 21 is opened, and the electric motor 14 is stopped.

Therefore, the saw wheel 2 is stopped by the braking force exerted by the brake lining 12.

As explained above, according to the present invention, there is an effect that the band saw can be operated stably and safely.

[Brief explanation of the drawing]

Figures 1 and 4 are diagrams showing one embodiment of the motor drive control device of the present invention. Figure 2 shows the band saw blade.
FIG. 3 is a front view of the entry/exit detection means for detecting entry/exit, FIG. 3 is a front view of the braking detection means for detecting the presence or absence of operation of the braking device, and FIG. 4 is a circuit block diagram of the motor drive control device of the present invention. . 1...Supporting member, 2...Saw wheel, 3.
... Band saw blade, 5゜7, 13 ... Detection means, 8 ... Roller, 9 ... Arm, 1
1...Brake pedal, 14...Electric motor, 15...Start switch, 16...
Stop switch, 17.18...and gate,
19... Latch circuit, 20... Relay coil, 21... Normally open relay contact.

Claims (1)

[Scope of utility model registration request] A bandsaw machine comprising two saw wheels provided with a braking device, a band saw blade suspended between the two saw wheels, and an electric motor for rotationally driving the saw wheels. a first detection means for detecting whether the degree of tension of the band saw blade is good or bad; a second detection means for detecting whether the band saw blade is moving in or out; and a third detection means for detecting whether or not the braking device is operating. detecting means, the first detecting means detects whether the tension is good, the second detecting means detects whether the blade goes in or out, and the third detecting means detects that the electric motor is not braked. 1. An electric motor drive control device for a bandsaw machine, characterized by comprising means for driving a band saw.