JPS591565B2 - Safety devices for wood processing machines - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a safety device for a wood processing machine, and particularly to a safety device for a wood processing machine that immediately stops the wood processing machine when a person approaches a dangerous part of the wood processing machine.

A wood processing machine, for example, a saw that cuts wood, has a disc-shaped saw blade that rotates at high speed and is placed on a base, and cuts the wood while pressing it against it, or it cuts at a high speed that cuts the wood that is fixed to the base. The wood is cut into a desired size by moving the disc-shaped serrations while pressing against them.

The saw blades of the above-mentioned saw machine rotate at high speed, and are extremely dangerous because they can instantly cut or injure people, including fingers and fingers.

Therefore, a frame is usually installed around the saw blade to prevent hands and fingers from touching the saw blade, but if the frame is too tight, it will interfere with wood processing and the protection is incomplete. It is.

In addition, a wire may be stretched over the dangerous area and both ends of the wire may be fastened to a limit switch sensor, so that when a finger touches the wire, the limit switch will activate and stop the rotating mechanism, or a wire may be placed at a distance from the dangerous area. Some devices are equipped with an infrared light emitting element and a light receiving element that receives the infrared beam sent from the infrared light emitting element, and stop the rotating mechanism when the infrared beam is blocked by a finger or the like.

However, these are limited to limit switches, light emitting elements,
Since the light-receiving element must protrude from the surface of the substrate, if a piece of wood is accidentally brought into contact with the part housing the light-emitting element during work, a failure will occur immediately.

Furthermore, since these protrude from the surface of the base or the like, they may obstruct the work, and there may also be inconveniences in that the saw blade may stop if the wood blocks the light beam or comes into contact with the wire.

Furthermore, since the wire is stretched in a straight line and the infrared beam also travels straight, it is not possible to curve the sound to be detected, which imposes significant restrictions on the installation location of these detection mechanisms, and the use of wood processing machines. The drawback is that the degree of freedom in design is limited.

The present invention is a novel invention that improves the above-mentioned conventional drawbacks, and its purpose is to enable a human body detection mechanism to be installed without protruding from the base of a wood processing machine or the wall of a saw blade rotation mechanism. Moreover, the object of the present invention is to provide a safety device in which the detection mechanism can be formed into any shape and can immediately stop the wood processing machine when a human body comes into contact with or comes very close to the detection mechanism.

Next, one embodiment of the present invention will be described in detail with reference to the drawings.

FIG. 1 is a perspective view of a vertical saw machine.

In the figure, 1 is a base made of iron material.

A horizontally long surface plate 2 is mounted on the base 1.

This surface plate 2 is a part on which the lower edge 3a of a wooden board 3, which is a workpiece, is positioned and placed. 2a
is installed.

At the rear of the base 1, as shown in FIG. 2, a main pillar 4 is erected.

Reference numeral 5 denotes a backing plate installed obliquely between the base 1 and the upper end 4a of the main pillar 4, and the back surface of the wooden board 3 is brought into contact with this backing plate 5.

A support column 6 is provided between the upper end 4a of the main column 4 and the base 1, and is arranged at an appropriate distance from the backing plate 5.

7 is a pressing member.

The holding member 7 is made of wood impregnated with an insulator such as oil or paraffin.

Metal plate electrodes 7a and 7b for detecting the approach of a human body are attached to both side edges of the holding member 7, and this state is clearly shown in FIG.

Further, a slit 7c into which the sawtooth disk 8 is inserted is formed in the center of the holding member 7.

Crank members 9 and 10 are pivotally mounted on the support column 6, one end of which is rotatably attached to the holding member 7, and the other end rotatably attached to the drive rod 11.

12 is an air cylinder installed on the support column 6;
It drives the drive rod 11 in the vertical direction.

At the center of the rear surface of the backing plate 5, there is a guide post 1 in the vertical direction.
3 is erected, and a sawtooth disk support mechanism 14 is held on this guide column 13 so as to be movable in the vertical direction along this guide column.

Note that 14a is a carrier that holds the sawtooth disk support mechanism 14, and 14b is an air cylinder that moves the sawtooth disk 8 in the front-back direction.

15 is a motor that moves the sawtooth disk support mechanism 14 in the vertical direction along the guide column 13; 16 is a wire that supports the sawtooth disk support mechanism 14; 17 is a weight fastened to the tip of the wire 16; and 18 is air. Control boxes 19 and 20, which house control circuits such as a compressor for compressing air sent to the cylinders 12 and 14b and a motor 15, as well as main parts of an approach detection mechanism to be described later, are flexible ducts that suck out sawdust.

Note that a vertically long slit 5a (shown in the third figure) is formed at a position of the backing plate 5 facing the support column 6, and the sawtooth disk 8 enters and exits through this slit 5a.

On both sides of the slit 5a of the backing plate 5, detection parts 5b and 5c made of an insulator are formed, and an electrode 5 is formed on the surface thereof.
d, 5e are attached.

Reference numeral 21 is a foot switch for control, and reference numeral 22 is a positioning knob for positioning the wooden board 3, and their set positions can be adjusted freely.

Next, before moving on to an explanation of the safety device, the operation of cutting a wooden board will be explained.

As shown in FIG. 1, the wooden board 3 is slid on the surface plate 2 and the leading edge is brought into contact with the positioning knob 22 through the slit between the backing plate 5 and the holding member 7, and then the foot switch 2 is pressed.
Press 1.

This operation activates the operation sequence mechanism in the control box 18, which first sends air into the air cylinder 12 to move the drive rod 11 in the direction of arrow A, and rotates the crank members 9 and 10 to press down the presser member 7. Press against the wooden board 3 to firmly fix the wooden board onto the backing board 5.

When this operation is completed, the sawtooth disk support mechanism 14 rises to a preset height, and then the sawtooth disk 8 begins to rotate at high speed.

When the sawtooth disc 8 reaches a predetermined rotation speed, the air cylinder 14
Air is sent to b, and the sawtooth disc 8 moves in the direction of the wooden board 3 within the slit 5a and cuts into the wooden board 3.

When the motor 15 starts rotating, the sawtooth disk support mechanism 14 starts to descend along the guide columns 1-3, so the sawtooth disk 8 descends along the slit and cuts the wooden board 3.

When the sawtooth disk support mechanism 14 is completely lowered, the sawtooth disk 8
When the wood board 3 is cut, air is sent to the air cylinder 14b and the serrated disk 8 is drawn into the slit 5a,
Stop rotation.

When the sawtooth disk 8 stops, air is sent to the air cylinder 12 to move the drive rod 11 in the direction of arrow B, rotate the crank members 9 and 10, and release the presser member 7 from the wooden board 3.
The operation sequence of one cycle is completed.

FIG. 4 is a block diagram showing the safety device according to the present invention, in which 23 is an induction motor that drives the sawtooth disk 8, and 24 is a rotation shaft ratio that connects the induction motor 23 and the sawtooth disk 8. The attached brake disc, 26 is a brake shoe, 27 is a brake control device, 28 is an electromagnetic contactor, 29 is a three-phase commercial power supply, 30 is a proximity detection device, and 30a is a sensitivity adjuster.

Note that the electrodes 7a and 7b are electrically connected to each other, and the electrodes 5d and 5e are electrically connected to each other.

Next, the operation of the safety device will be explained.

In a normal state, that is, when there is no human body near the sawtooth disk 80 or its movement path, the approach detection device 30 does not emit any signal.

Therefore, the start signal is transmitted from the terminal S to the electromagnetic contactor 28.
is turned on, an electrode is added to the induction motor 23 and it rotates, causing the sawtooth disc 8 to rotate.

Then, when the start signal applied to the electromagnetic contactor 28 is cut off, the electromagnetic contactor 28 is turned off and the induction motor 23 is stopped.

When the sawtooth disc 8 is rotating, the electrode? When a human body touches or approaches electrodes 5d and 5e, a signal is emitted from the proximity detection device 30.

This signal is applied to the electromagnetic contactor 28 and the brake control device 27.

Therefore, the electromagnetic contactor 28 is immediately turned off and the supply of power to the induction motor 23 is stopped.

Then, the brake control device 27 is activated to press the brake shoe 26 against the disk 24 and instantly stop the sawtooth disc 8. At the same time, the motor 15 is also stopped, and all power supply to the entire device is stopped. Ru.

At this time, the holding member 7 releases the holding of the wooden board 3, returns to the initial state, and the operation of the entire apparatus is completely stopped.

Therefore, by the time the human body reaches the sawtooth disk 8, it has already stopped, and the human body is safe.

And electrode 5 d j 5 e t 7 a > 7
When the human body moves away from b, the signal from the approach detection device 30 becomes null (no longer), and the wood processing machine automatically returns to its original operating state and starts cutting the wood.

It should be noted that it may be dangerous if the wood processing machine starts immediately after the human body is removed, so when the wood processing machine is stopped by the safety device according to the present invention, do not start the wood processing machine immediately and wait for the recovery time. A switch may be provided and the wood processing machine may be started only when the return switch is turned on.

In this case, if you operate the return switch and the foot switch 21 in this order, the motor 15 will start, and the foot switch 21 will start.
With this operation, the electromagnetic contactor 28 is turned on, the brake control device 27 is operated, and the sawtooth disk 8 starts rotating again.

Note that by adjusting the sensitivity adjuster 30a, the approach distance of the human body at which the safety device operates can be freely set.

FIG. 5 is a specific circuit diagram of the approach detection device.

In FIG. 5, a coil L1, capacitors C1 and C2, and a transistor TR1 constitute a Colpitts oscillation circuit.

Transistor TR2 is a switching transistor,
Transistors TR3 and TR4 are transistors that drive relay RY.

electrode? When a human body is not close to a, 7b, 5d, and 5e, the oscillation circuit oscillates at the frequency determined by the coil L1 capacitor CI and C2, and this signal is applied to the transistor TR2, which turns on. , transistors TR, 3, and TR4 are in an OFF state, and a contact ry of a relay RY is in an OFF state.

Is the human body an electrode? When approaching any one of at7bt5d and 5e, the oscillation circuit stops oscillating, so transistor TR2 turns off, and transistors TR3 and T
R4 turns on, operating relay RY and turning on contact ry.

When this contact ry is turned on, a signal is emitted from the approach detection device 30.

Note that by adjusting the sensitivity adjuster 30a, the oscillation intensity can be changed, and the distance over which the approach detection device 30 operates when a human body approaches the electrode of the approach detection device 30 can be adjusted.

In the above embodiment, the electrode 5d for human body detection is also attached to the backing plate 5,
5e, but the slit between the presser member 7 and the backing plate 5 is small, and when a human body approaches the slit 5a, the presser member 7
If the electrodes 7a and 7b can detect this, the electrodes 5d and 5e can be omitted.

Further, in the above embodiment, when the sawtooth disk 8 is at the lowest end, even if the electrode 5e is touched or approached at the top end of the slit 5a, the safety device is activated and the sawtooth disk 8 is stopped. , work efficiency deteriorates.

In order to eliminate such inconvenience, in another embodiment, as shown in FIG.
~5e-6, and in parallel with this, electrode 5e-1'
The left and right electrodes are connected by lead wires 31 to 36, respectively, such that electrodes 5e-1 and 5e-1' are connected by providing electrodes 5e-6' to 5e-6'.

And at any position, the electrodes 5 e-1' to 5
A movable contactor 37 that always comes into contact with two adjacent electrodes of e-6' is provided, and this is connected to the contact detection device 30.

In this embodiment, as the sawtooth disc 8 moves, the movable contactor 37 also moves, so the contact detection device 30 operates only when a human body approaches or contacts the electrode near the sawtooth disc 80, which improves work efficiency. It has the advantage of getting better.

In addition, although the present invention has been implemented on a vertical saw machine in all of the embodiments so far, it is not impossible to implement the present invention on a horizontal saw machine, and it is also possible to implement the present invention on a horizontal saw machine. It can also be applied to other wood processing machines with almost no changes.

In addition, the structure of the electrode is not limited to a straight one, but can be curved, spherical, or any other shape.

As explained in detail above, according to the present invention, the member for detecting contact can be formed into any shape by aligning the contact detection member with the shape of the detection part, so that the safety device attached to the wood processing machine can be used as a safety device. The degree of freedom in design has increased compared to conventional designs, making design easier.

In addition, because the component that detects the approach or contact of a human body does not protrude like in the past, there is no longer any failures such as damage to the safety device due to wooden objects coming into contact with the detection part, and it is also Unlike the case where a safety device does not operate unless a human body blocks the light beam or touches a wire, the safety device operates and stops the dangerous part just by a human body approaching the detection part. The safety level is improved compared to the conventional method, and the rotating part does not stop even if a piece of wood approaches or comes into contact with the detection part, which improves work efficiency.

[Brief explanation of drawings]

Figure 1 is a perspective view of the vertical saw machine, Figure 2 is a side view of the same, Figure 3 is a partially enlarged perspective view, Figure 4 is a block diagram of the safety device, and Figure 5 is the circuit of the approach detection device. FIG. 6 is a circuit diagram of an electrode portion showing another embodiment. In the figure, 1 is a base, 2 is a surface plate, 3 is a wooden board, 4 is a main pillar, 5 is a backing plate, 5a is a slit, 5 b and 5 c are detection parts, 5 d and 5 e are electrodes, and 6 is a Support column, 7 is a holding member, 7a, 7b are electrodes, 8 is a sawtooth disk, 9°10 is a crank member, 11 is a drive rod, 12 is an air cylinder, 13 is a guide column, 14 is a sawtooth disk support mechanism, 14b is an air cylinder, 15 is a motor, 16 is a wire, 17 is a weight, 18
is the control box, 19.20 is the flexible duct, 2
1 is a foot switch, 22 is a positioning knob, 23 is an induction motor, 24 is a disc, 25 is a rotating shaft, 2
6 is a brake shoe, 27 is a brake ILJ control device, 2
8 is an electromagnetic contactor, 29 is a three-phase commercial electric line, 30 is a proximity detection device, and 30a is a sensitivity adjuster.

Claims (1)

[Scope of Claims] 1. A wooden board placed along the backing plate is pressed against the backing plate using a holding member made of an insulating material, and a saw disposed near the holding member is cut into a straight line provided on the backing plate. In a wood processing machine that protrudes from a slit and moves it to saw a wooden board, an insulating material is formed in a straight line on both sides of the slit, and a linear electrode for detecting the approach of a human body is pasted on the surface of each of the insulating materials. The approach detection device has two detection parts attached to the electrode, an electric circuit that emits a detection signal when a human body approaches or touches the electrode, and an electric circuit that adjusts the sensitivity of emitting the detection signal, A safety device for a wood processing machine characterized by cutting off power to a motor that drives a saw and forcibly stopping the saw by a brake control device based on a detection signal emitted by the device. 2. Press the wooden board arranged along the backing plate against the backing plate with a holding member made of an insulating material, and make the saw arranged near the holding member protrude from the linear slit provided in the backing plate. In a wood processing machine that moves to saw a wooden board, two insulators are formed in a straight line on both sides of the slit, and a plurality of electrodes for detecting the proximity of a human body are attached in a row to the surface of each insulator. A detection part, a movable contact that always comes into contact with two adjacent electrodes among the plurality of electrodes and moves with the movement of the saw, and detects when a human body approaches or contacts the electrode that is in contact with the movable contact. It has an approach detection device equipped with an electric circuit that emits a signal and an electric circuit that adjusts the sensitivity of emitting the detection signal, and the detection signal that the approach detection device emits cuts off the power to the motor that drives the saw and also brakes the saw. A safety device for a wood processing machine characterized by forcibly stopping a saw using a control device.