JPS64185B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION <Industrial Application Field> The present invention relates to a polishing device for a belt sander used for grinding and polishing wood.

<Prior art> In the belt sander, a cleaning liquid is sprayed from a cleaning liquid injection nozzle onto the abrasive grain surface of the polishing belt that is stretched around a plurality of support rolls to clean the abrasive grain surface and prevent clogging. This is widely known to the general public.

In addition, in order to prevent the cleaning liquid supplied to the surface of the belt from acting on the workpiece, a drain roll is pressed against the support roll on which the abrasive belt is wrapped, via the belt, and the pressure is applied to the belt surface. A device for removing excess cleaning liquid is known as disclosed in Japanese Patent Publication No. 49-3438 and Japanese Patent Publication No. 51-43237.

By the way, the roll located farthest from the running material path, such as the support roll 9 in FIG. 1, usually serves as a steering roll and cannot be constantly pressed against the draining roll due to its oscillating motion. . Therefore, in the above structure, the drain roll is brought into pressure contact with the support roll on the running material path side. However, in this case, the drain roll increases the width of the polishing device on the running material path side, and as a result, it is necessary to increase the distance between the pressure rolls disposed before and after the polishing device. On the other hand, in order to convey the workpiece well, it is necessary to apply the pressing force of the rolls to the workpiece at all times during the feed. Therefore, the shortest scale of the workpiece is the pressure of the pressure roll. Determined by interval. However, due to the above reasons,
Since the spacing becomes large, the above configuration results in severe restrictions on the application of short-length processed materials.

In addition, some of the support rolls on the running material path side have a mechanism that can be applied to roll grinding by repositioning them to the running material path side rather than the tread pressure pad.
This movement makes it impossible to maintain good contact with the draining roll, thus making it impossible to apply the mechanism. As described above, the above configuration has various drawbacks.

Therefore, as shown in FIG. 4, a receiving roll b is arranged inside the abrasive belt a separately from the supporting roll, and a draining roll c is pressed against the receiving roll b side via the belt a. Due to the pressure contact force, the draining roll c
It has been proposed to eliminate the drawbacks of the conventional structure by rotating the belt A to remove excess liquid.

<Problems to be Solved by the Invention> By the way, when the draining roll c is pressed against the belt a at the straight running portion of the belt a, the pressing force becomes a resistance to the running of the belt a.
As shown in Figure 4, belt a has wrinkles x at the draining part.
occurs. When the wrinkles x occur, the cleaning liquid tends to scatter around the outside of the designated area. In addition, in the conventional configuration, one of the support rolls is used as a drive roll, and the other support rolls are driven as the belt runs.
Since it rotates freely, due to the pressure contact resistance,
The belt tends to slip against the support roll, making it impossible to grind or polish the workpiece to a predetermined thickness.

An object of the present invention is to provide a polishing apparatus having a configuration capable of eliminating the above-mentioned drawbacks.

<Means for Solving the Problems> The present invention comprises: a cleaning liquid spray nozzle installed opposite to the abrasive grain surface of an abrasive belt stretched around a plurality of support rolls; Polishing comprising a draining device disposed between the polishing area near the passage side and consisting of a receiving roll located inside the polishing belt and a draining roll that presses against the receiving roll side through the polishing belt. The device is characterized in that the support roll is driven by all wheels, and the drain roll is rotationally driven by a drain motor that is driven in synchronization with a drive motor for the support roll and rotates proportionally.

<Operation> Since driving force is applied to the draining roll by the draining motor, a feeding force is applied by the draining roll to the abrasive belt in the draining section. Therefore, the belt runs without succumbing to the pressure contact resistance by the draining roll, and no wrinkles x are generated at the entrance of the pressure contact portion. Furthermore, since the driving force acts on all of the support rolls around which the belt is wound, slippage of the belt on the support rolls is eliminated as much as possible.

<Example> FIG. 1 shows an overview of a belt sander machine.

Here, 1 is a running material device, and a drive roll 2
An endless running material belt 4 is wound around the driven roll 3, and the upper horizontal running section is used as a material feeding section.

A material feeding passage 5 is placed on the material running device 1,
A polishing device 6 is provided.

The polishing device 6 has support rolls 7 and 8 disposed along the material feeding path 5 and a support roll 9 which also serves as a steering wheel above the support rolls 7 and 8 and is arranged in a triangular shape.
A polishing belt 10 is wrapped around the belt 9. The support roll 9 is urged outward by a pressure cylinder 11 (see FIG. 2), and also functions as a tension roll that applies tension to the polishing belt 10.

A treading device 12 is disposed inside the polishing belt 10 between the support rolls 7 and 8, and its lower surface serves as a polishing portion. The treading device 12 pushes the polishing belt 1 when the front end of the workpiece reaches the polishing site.
0 to the material feeding path 5 side, and timing control is performed to release the treading force when the workpiece passes, and has the function of properly polishing the upper surface of the workpiece.

A cleaning liquid spray nozzle 14 is disposed between the support rolls 8 and 9 with its mouth end facing the abrasive grain surface of the polishing belt 10 , and a receiver located inside the polishing belt 10 is located directly below the cleaning liquid spray nozzle 14 . A draining device consisting of a roll 15 and a draining roll 16 located on the outside is provided. The draining roll 16 is covered with an elastic body such as rubber, and is covered with a pressing cylinder 17.
(See FIG. 2), it can be arbitrarily converted into a pressure contact position with respect to the abrasive belt 10 and a non-press contact position.

In this non-pressure contact position, the draining roll 16
is out of contact with the abrasive belt 10, and in this state, the receiving roll 15 is released from contact with the abrasive belt 10. For this reason, the polishing belt 1
0 does not come into contact with either the receiving roll 15 or the draining roll 16 and can be run without resistance.

In addition, in the pressure contact position, the draining roll 16
The abrasive belt 10 is pressed against the receiving roll 15 side, and in this state, the abrasive belt 10 is pressed against the receiving roll 15.
5 and a draining roll 16. In this state, the cleaning liquid is sprayed from the cleaning liquid injection nozzle 14 onto the surface of the polishing belt 10, and the liquid is stored in the V-shaped gap 18 formed between the polishing belt 10 and the draining roll 16. The mouth end of a liquid collection duct 19 is disposed above the V-shaped gap 18, and the cleaning liquid stored in the gap 18 is recovered by its suction action. Further, a saucer 21 is provided at the lower part of the drain roll 16, and the cleaning liquid dripped from the surface of the drain roll 16 is collected.

In addition, at the front and rear of the polishing device 6, there are pressure rolls 24, 24 that are urged toward the material feeding path 5 by bullets.
is provided.

Next, the main part of the present invention will be explained with reference to FIG.

Sprockets 25, 26, and 27 are fixed to the shaft ends of the support rolls 7, 8, and 9, respectively, and an endless chain 28 is stretched around the sprockets 25-27. At a location between the sprockets 25 and 26, a tension sprocket 30 is engaged on the inside of the chain 28, which is biased outwardly by a cylinder 29 to maintain its tension. Further, sprockets 31 and 32 are also fixed to the shafts of the support rolls 7 and 8, and an endless chain 34 is connected to the sprocket 33 provided on the drive shaft of the drive motor _M1 and the sprockets 31 and 32. It is being handed over.

On the other hand, a sprocket 35 is also fixed to the rotating shaft of the draining roll 16, and linked by an endless chain 37 to a sprocket 36 fixed to the drive shaft of the draining motor _M2 . The chain 37 is tensioned by a tension sprocket 38.

The draining motor _M2 is driven in synchronization with the drive motor _M1 , and is given a rotation proportional to the rotation of the drive motor _M1 , so that the circumferential speed of the draining roll 16 matches the running speed of the polishing belt. There is.

An example of a drive control mechanism for synchronously driving the drainer motor _M2 and the drive motor _M1 will be described with reference to FIG.

A tachogenerator 40 is provided on the drive shaft of the drive motor _M1 . The tachogenerator 40 generates an alternating current voltage proportional to the rotational speed of the drive shaft. The output power of the tachogenerator 40 is converted into direct current by a rectifier 41, and is input to a speed controller 42 that controls the rotation speed of the single-phase water drainer motor _M2 . The speed controller 42 generates an AC voltage proportional to the input DC signal voltage, and by adjusting the speed controller 42, it is possible to match the circumferential speed of the draining roll 16 with the running speed of the polishing belt. becomes.

FIG. 3 shows another embodiment of the drive control mechanism, which is most suitable when a three-phase motor is used as the drainer motor _M2 .

Here, a slit plate 50 is fixed to the drive shaft of the drive motor _M1 , and an encoder 51 for detecting the number of slits passed through the slit plate 50 is provided on the periphery of the slit plate 50. The encoder 5
No. 1 detects the amount of rotation as a digital value by reading the number of slits. The detected value of the encoder 51 is converted into an analog value by a D/A converter 52, and its output is input to an inverter 53. The inverter 53 controls the frequency of the light current voltage input to the drainer motor _M2 so as to correspond to the frequency of the drive motor _M1 . Therefore, the rotation speed of the water drainer motor _M2 is
The circumferential speed of the draining roll 16 is adjusted to match the running speed of the polishing belt.

In this configuration, when the drive motor M ₁ is driven, the support rolls 7 and 8 are rotated by the running of the chain 34, and this rotational force is transferred to the chain 28.
is transmitted to the support roll 9 by. Therefore, each support roll 7, 8, 9 becomes an all-wheel drive, causing the abrasive belt 10 wrapped around the roll group to run. Furthermore, with the drive control mechanism illustrated above,
The draining motor _M2 has a rotation speed proportional to that of the drive motor _M1 , and is connected to the draining roll 1 via a chain 37.
6 is driven and rotated.

When the excess cleaning liquid is removed by the draining roll 16, the driving force is applied to the draining roll 16, so that the abrasive belt 10 is fed as a result of its pressure contact. For this reason, the polishing belt 10 runs while being maintained in a tensioned state at the drain section. Furthermore, by all-wheel drive of the support rolls 7, 8, and 9, slips on the abrasive belt 10 are also eliminated as much as possible.

Further, when the supply of cleaning liquid is stopped and the pressure cylinder 17 is driven in the reverse direction to bring the draining roll 16 to the non-pressing position, it is wasteful to continue driving the draining motor _M2 . By interposing a switch in the drive control mechanism that is converted in synchronization with the reverse drive of the press cylinder 17, the water drainer motor _M2 can also be made non-driven.

On the other hand, when the draining roll 16 remains in a non-rotating state and comes into pressure contact with the polishing belt 10 by driving the press cylinder 17 in the forward direction, a large load is applied to the polishing belt. Therefore, for example, it is desirable to have a configuration in which when the position setting switch for the draining roll 16 is pressed, the draining motor _M2 is first driven, and then the pressing cylinder 17 is driven by timing control such as a timer or counter.

Incidentally, even if the water drainer motor _M2 is always rotated, there is no problem in achieving the effects of the present invention. In this case, the timing control is of course
Not needed.

Furthermore, by making it possible to adjust the speed controller 42 or inverter 53 of the drive control mechanism using a rotary switch or the like, it is possible to easily cope with wear and replacement of the draining roll 16, and to adjust its circumferential speed. It is possible to always maintain the optimum condition. In addition, this makes the circumferential speed of the draining roll 16 different from the running speed of the polishing belt 10,
It also becomes possible to adjust the drainage effect. That is, due to the change in the rotational speed of the draining roll 16, the circumferential surface of the draining roll 16 slides on the polishing belt 10 and scrapes water off the surface of the polishing belt 10, so that the surface of the polishing belt 10 is not drained. It will be adjusted to be smaller. In addition, the polishing belt 10
Usually, the circumferential speed of the draining roll 16 is made to match the running speed of the polishing belt 10.

In addition, the support roll 8 is made movable by an eccentric shaft or the like, as shown by the chain line in FIG. Good too. Due to this positional change, the upper surface of the workpiece is subjected to roll grinding by the support roll 8, and heavy grinding becomes possible. In this case, in order to enable movement of the support roll 8 and maintain tension in the chain 34, the chain 34 is made to have a sufficient length;
A tension device is arranged on its inner surface.

Although the above-described embodiments have been described with respect to a top surface grinding type, the present invention can also be applied to a bottom surface grinding type.

<Effects of the Invention> As described above, in the present invention, the support roll is all-wheel drive, and the drive rotational force is applied by the draining motor _M2 to the draining roll that is in pressure contact with the abrasive belt.
This prevents the occurrence of wrinkles x at the draining portion caused by the pressure of the abrasive belt, slips of the abrasive belt, etc., and allows the abrasive belt to run evenly, making the action of the drain roll more effective. It can be taken as a thing. In addition, since the draining roll is driven separately from the drive roll _M1 by the draining motor _M2 ,
The drive of the draining roll can be easily controlled, and its drive form can be varied. It has excellent effects such as

[Brief explanation of drawings]

The accompanying drawings show embodiments of the present invention; FIG. 1 is a schematic side view, FIG. 2 is a schematic side view showing a drive control mechanism, FIG. 3 is a schematic diagram of another embodiment of the drive control mechanism, and FIG. The figure is a side view of the main parts showing the conventional drawbacks. 6; Polishing device, 7, 8, 9; Support roll, 1
0; Polishing belt, 14; Cleaning liquid spray nozzle, 1
5; Receiving roll, 16; Draining roll, 17; Pressing cylinder, 28, 34, 37; Chain, 40;
Tachometer generator, 42; Speed controller, 51; Encoder, 53; Inverter,
M ₁ ; Drive motor, M ₂ ; Draining motor.

Claims (1)

[Scope of Claims] 1. A cleaning liquid spray nozzle installed opposite to the abrasive grain surface of an abrasive belt stretched over a plurality of support rolls, and a cleaning liquid spray nozzle along the running direction of the belt from the spray nozzle to the polishing area near the running material path side. A polishing device comprising a receiving roll disposed between the polishing belt and located inside the polishing belt, and a draining device comprising a draining roll that presses against the receiving roll through the polishing belt. A grinding device for a belt sander machine, characterized in that it is an all-wheel drive system, and the drain roll is rotationally driven by a drain motor that rotates proportionally in synchronization with the drive motor of the support roll.