JP2023150492A - Bandsaw - Google Patents

Abstract

To provide a bandsaw capable of efficiently and automatically adjusting, a drive speed, without experienced techniques.SOLUTION: A bandsaw 10 comprises: an endless saw blade 24; a pair of wheels 26 to which the saw blade is wound; cutting means 20 having a rotation motor 28 which is connected to one wheel and is rotated; and feeding means 30 having a feeding motor 32 which moves the cutting means in a cutting direction. The bandsaw further comprises: a vibration measurement sensor 40 for detecting vibration which is generated in the cutting; a saw blade vertical position measurement sensor 50 for detecting a height position of a saw blade; a saw blade horizontal position measurement sensor 51 for detecting a horizontal position of the saw blade; a determination part 60 for comparing a measured value with a vibration set value of the vibration measurement sensor, a measured value with a saw blade height change set value of the saw blade vertical position measurement sensor, and a measured value with a saw blade position set value of the saw blade horizontal position measurement sensor; and a control part 70 for, on the basis of determination by the determination part, controlling at least one of a rotation speed of the rotation motor and rotation speed of the feeding motor.SELECTED DRAWING: Figure 1

Description

The present invention relates to a band saw that cuts large structures using an endless saw blade.

Band saws equipped with endless saw blades are used in dismantling large structures such as large-diameter pipes. If a band saw is operated at the wrong speed, problems such as chipping of the saw blade can occur, so adjusting the speed is difficult and must be done by experienced and skilled operators. Due to the aging and decreasing number of these experts and the fact that it takes time to acquire and develop techniques for optimal driving speeds, there has conventionally been a technology for automatically adjusting various driving speeds.

The band saw disclosed in Patent Document 1 detects the load of the band saw at a depth of cut that changes continuously from the start to the end of the cutting process, and cuts the workpiece according to a preset optimal processing pattern. Cutting is performed at the highest feed rate within the range that does not cause damage such as chipping.

The wafer band saw disclosed in Patent Document 2 detects an increase or decrease in cutting resistance during cutting from an increase or decrease in the amount of electric power of a first motor that rotates the saw blade circumferentially, and detects an increase or decrease in cutting resistance during cutting based on an increase or decrease in electric power of a first motor that rotates the saw blade circumferentially, , controls to increase/decrease the cutting speed of the second motor that raises and lowers the saw blade.
However, with the technology of Patent Document 1, if the shape etc. of the cut object is known in advance, it is possible to determine the maximum feed rate setting value, but it is Therefore, it is difficult to obtain the setting values in advance.
In addition, with the technology of Patent Document 2, if the motor output used when dismantling a large structure is excessive relative to the load, it is impossible to detect minute changes in cutting resistance, and it is difficult to control the cutting speed. I can't.

Japanese Patent Application Publication No. 2-214608 Japanese Patent Application Publication No. 2005-28620

In view of the above-mentioned problems of the conventional technology, the problem to be solved by the present invention is to efficiently automatically adjust the operating speed without the need for experienced technology, and automatically adjust the feed rate while avoiding chipping or twisting of the saw blade. Our goal is to provide a band saw that maximizes your performance.

As a first means for solving the above problems, the present invention provides an endless saw blade, a pair of wheels around which the saw blade is wound, and a rotation motor connected to one of the wheels to drive the rotation. A band saw comprising a cutting means having a cutting means and a feeding means having a feeding motor for moving the cutting means in a cutting direction,
A vibration measurement sensor that detects vibrations generated during cutting,
a saw blade vertical position measurement sensor that detects the height position of the saw blade;
a saw blade horizontal position measurement sensor that detects the horizontal position of the saw blade;
Compare the measurement value of the vibration measurement sensor and the vibration setting value, the measurement value of the saw blade vertical position measurement sensor and the saw blade height change setting value, and the measurement value of the saw blade horizontal position measurement sensor and the saw blade position setting value. a determination unit to
An object of the present invention is to provide a band saw comprising a control section that controls at least one of the rotation speed of the rotation motor and the rotation speed of the feed motor based on the determination of the determination section.
According to the first means, control can be performed to optimize the circumferential speed or feed speed based on physical changes such as frame vibration and saw blade positional deviation.

As a second means for solving the above problems, the present invention provides, in the first means, the saw blade vertical position measurement sensor is attached to the lifting frame of the cutting means to detect the height position of the saw blade. An object of the present invention is to provide a band saw characterized by a laser sensor that provides
According to the second means, it can be seen from the detected value of the height position of the saw blade that escape of the saw blade in the direction opposite to the feed (hereinafter referred to as cutting delay) has occurred.

The present invention provides a third means for solving the above problem, in which in the first means, the saw blade horizontal position measurement sensor is attached to the lifting frame of the cutting means to detect the horizontal position of the saw blade. An object of the present invention is to provide a band saw 10 characterized by a laser sensor.
According to the third means, it can be seen from the detected value of the horizontal position of the saw blade that the saw blade is twisted or bent.

The present invention provides, as a fourth means for solving the above-mentioned problem, that in any one of the first to third means, the vibration measurement sensor is connected to a column of a frame main body to which the feeding means is attached and an upper frame. An object of the present invention is to provide a band saw characterized in that a connection point is provided.
According to the fourth means, vibrations of the saw blade can be easily detected on the frame body.

As a fifth means for solving the above problem, the present invention provides that, in any one of the first to fourth means, a determination unit determines a sign of saw blade damage based on the measured value of the vibration measurement sensor and the vibration setting value. and controlling at least one of the rotation speed of the rotation motor and the rotation speed of the feed motor by a control unit based on the determination of the determination unit, thereby increasing the feed rate while avoiding damage to the saw blade. The purpose of the present invention is to provide a band saw that is characterized by maximum performance.
According to the fifth means, it is possible to determine signs of saw blade damage based on physical changes such as frame vibration and positional deviation of the saw blade, and perform control to maximize the circumferential speed or the feed rate.

According to the present invention, control can be performed to optimize the circumferential speed or feed speed based on physical changes such as frame vibration and saw blade positional deviation.

1 is a schematic configuration diagram of a band saw of the present invention. FIG. 3 is an explanatory diagram of a saw blade vertical position measurement sensor that detects a height position. FIG. 3 is an explanatory diagram of a saw blade horizontal position measurement sensor that detects the horizontal position. It is a process flow diagram using the band saw of this invention.

Embodiments of the band saw of the present invention will be described in detail below with reference to the drawings.

[Band saw 10]
FIG. 1 is a schematic diagram of the configuration of a band saw according to the present invention.
The band saw 10 of the present invention includes a frame body 12, an endless saw blade 24, a pair of wheels 26 around which the saw blade 24 is wound, and a rotation motor 28 that is connected to one of the wheels 26 and driven to rotate. a feeding means 30 having a feeding motor 32 for moving the cutting means 20 in the cutting direction; a vibration measurement sensor 40 for detecting vibrations applied to the saw blade 24 during cutting; and a vibration measuring sensor 40 for detecting the height position of the saw blade 24. The saw blade vertical position measuring sensor 50 detects the horizontal position of the saw blade 24, the saw blade horizontal position measuring sensor 51 detects the horizontal position of the saw blade 24, the measured value and vibration setting value of the vibration measuring sensor 40, the measured value of the saw blade vertical position sensor 50, A determination unit 60 compares the saw blade height change set value and the measured value of the saw blade horizontal position measurement sensor 51 with the saw blade position set value, and based on the determination of the determination unit 60, the rotation speed of the rotation motor 28 and , a control section 70 that controls at least one of the rotational speeds of the feed motor 32.

The frame body 12 has upper and lower frames 13 and 14 that are rectangular in plan view, and four pillars 15 located at the four corners between the upper and lower frames 13 and 14, and has a rectangular parallelepiped overall shape. There is. A cutting means 20, a feeding means 30, etc. are arranged in such a frame body 12.

The cutting means 20 has a saw blade 24, a pair of wheels 26, a rotation motor 28, and an elevating frame 29 on which these are arranged. The elevating frame 29 is a frame that moves up and down along the pillars 15 of the frame main body 12, and can cut the object by lowering the saw blade 24. A pair of elevating frames 29 are provided at both ends of the frame body 12 in the longitudinal direction. A pair of elevating frames 29 are equipped with sliders that engage with guide rails arranged on the pillars 15.

The feeding means 30 includes a ball screw 33, a lifting slider, and a feeding motor 32, and moves the lifting frame 29 up and down along the column 15. The ball screw 33 is provided upright along the pillar 15 on the outside of the pillar 15 of the frame body 12. The elevating slider disposed on the elevating frame 29 engages with the ball screw 33 and moves vertically along the longitudinal direction of the ball screw 33 in accordance with the rotation of the ball screw 33. The feed motor 32 is a drive source that rotates the ball screw 33. Such a feeding means 30 can be arranged in each frame of the pair of lifting frames 29, and by synchronously controlling the feeding motor 32, the saw blade 24 of the lifting frame 29 can be raised and lowered while rotating in a horizontal plane. .

The vibration measurement sensor 40 is an acceleration sensor placed on the frame body 12 to detect vibrations generated during cutting. More specifically, the vibration measurement sensor 40 is installed at the intersection of the upper end of the column 15 of the frame body 12 and the upper frame 13, that is, at the connection point. The measurement direction of the vibration measurement sensor 40 is arranged in the longitudinal direction of the frame body 12.
Such a vibration measurement sensor 40 can detect vibrations generated during cutting with high sensitivity at the upper part of the frame body.

The saw blade vertical position measuring sensor 50 is a laser sensor that detects the height position of the saw blade 24, and the saw blade horizontal position measuring sensor 51 is a laser sensor that detects the horizontal position of the saw blade 24. Both are attached to a fixture 52 attached to the lifting frame 29. It is located in The fixture 52 moves up and down together with the lifting frame 29.

FIG. 2 is an explanatory diagram of a saw blade vertical position measurement sensor that detects the height position. The saw blade 24 in the figure is rotating in a direction perpendicular to the plane of the paper. The sensor that detects the height position of the saw blade 24 is a pair of laser sensors arranged so that the upper end of the saw blade 24 is sandwiched between them. The height position of the saw blade 24 can be detected by changing the amount of irradiation due to the shielding. This allows the cutting delay of the saw blade 24 to be confirmed.

FIG. 3 is an explanatory diagram of a saw blade horizontal position measurement sensor that detects the horizontal position. The saw blade 24 in the figure is rotating in a direction perpendicular to the plane of the paper. The sensor for detecting the horizontal position of the saw blade 24 has a laser displacement sensor placed at an opposing position so that the side surface of the saw blade 24 can be irradiated with a laser, and the distance between the side surface of the saw blade 24 and the sensor is detected by laser irradiation. do. When this detection distance exceeds the saw blade position setting value, a load is applied from the vertical position of the saw blade 24, and a horizontal position shift that causes the saw blade 24 to twist can be detected, and bending can be detected.

The determination unit 60 uses the measured value and vibration setting value of the vibration measurement sensor 40, the measurement value and the saw blade height change setting value of the saw blade vertical position measurement sensor 50, and the measurement value and the saw blade horizontal position measurement sensor 51. Compare position settings.
The vibration setting value is set to several times the vibration value when the saw blade 24 is in a stable state, or a value that occurs before the saw blade 24 is damaged.
The saw blade height change setting value of the saw blade is the difference between the latest and previous saw blade height average values calculated from the measured values over a predetermined period of time. This difference changes rapidly when the feed rate is changed, and gradually approaches zero as time passes. The setting value for the saw blade height change was set to less than half of the automatic feed acceleration amount. For example, when the automatic feed acceleration amount is 0.25 mm/min, the average change amount threshold is set to 0.125 mm. In addition, the saw blade position setting value is set to exceed the horizontal position variation range (±0.5 mm) during normal cutting confirmed in the test.

The control section 70 controls at least one of the rotation speed of the rotation motor 28 and the rotation speed of the feed motor 32 based on the determination of the determination section 60 . Specifically, the control unit 70 sends control signals to the inverter of the rotation motor 28 and the servo amplifier of the feed motor 32, respectively, to control each speed.

[Judgment flow]
A determination flow using the band saw of the present invention having the above configuration will be described below. FIG. 4 is a process flow diagram using the band saw of the present invention.
(Step 1)
During operation of the band saw 10 of the present invention, the saw blade horizontal position measurement sensor 51 collects the saw blade position for a predetermined period of time, 1 second in this embodiment.
(Step 2)
It is determined whether the measured value of the saw blade horizontal position measurement sensor 51 exceeds the saw blade position setting value.

(Step 3)
When the measured value is greater than or equal to the saw blade position setting value, the saw blade 24 is not in a stable cutting state (steady state) and the saw blade 24 is bending. At this time, accelerating the feed speed and rotation speed will greatly affect the malfunction of the saw blade 24, so the feed motor 32 is stopped and the rotation motor 28 is maintained in operation. Continue operation for a predetermined period of time.
(Step 4)
It is determined again whether the measured value of the saw blade horizontal position measurement sensor 51 exceeds the saw blade position setting value.

(Step 5)
When the measured value is greater than the saw blade position setting value, it means that the saw blade is not in a steady state and excessive bending has occurred, so even if you continue as it is, there is a high possibility that problems such as saw blade damage will occur eventually. 24 inspections and maintenance are required, and the operation will be stopped.
(Step 6)
When the measured value does not reach the saw blade position setting value, the cutting bend of the saw blade 24 tends to decrease due to continued operation for a predetermined period of time, so the feed motor 32 is decelerated (for example, by 0.25 mm/ min, etc.).

(Step 7)
Restart feeding of the saw blade 24 to perform cutting, and repeat step 1 and subsequent steps.
(Step 8)
When the measured value does not reach the saw blade position setting value, the saw blade 24 is not bent.
Further, while the band saw 10 of the present invention is in operation, the vibration measurement sensor 40 collects vibrations and the saw blade vertical position measurement sensor 50 collects the height of the saw blade for a predetermined period of time, 30 seconds in this embodiment.

(Step 9)
It is determined whether the measured value of the vibration measurement sensor 40 exceeds the vibration setting value. A determination unit 60 determines a sign of saw blade damage based on the measured value of the vibration measurement sensor 40 and the vibration setting value.
(Step 10)
When the measured value does not reach the vibration set value, check the height change of the saw blade 24.
When the height exceeds the predetermined saw blade height change setting value, the saw blade is not in a steady state and the cutting lag occurs, and increasing the saw blade feed rate will put an excessive load on the saw blade. Repeat step 1 onwards.

(Step 11)
When the height change of the saw blade 24 has not reached the saw blade height change set value, the feed rate of the saw blade 24 can be accelerated in a steady state.
It is determined whether the feed rate of the saw blade 24 has reached the upper limit value. If it has already been reached, repeat Step 1 and subsequent steps.
(Step 12)
When the upper limit of the feed rate of the saw blade 24 has not been reached, the feed rate is accelerated (for example, +0.25 mm/min) and Step 1 and subsequent steps are repeated.

(Step 13)
When the measured value reaches the vibration set value, check how often the vibration set value is exceeded. The frequency is a count of how many times the vibration setting value is exceeded in a predetermined period of time. In this embodiment, as an example, the vibration excess setting value is set to 30 times in which the vibration setting value is exceeded during a predetermined period of time (for example, 30 seconds).
(Step 14)
Steady vibration is occurring when the excessive vibration setting value is exceeded. Therefore, the feed speed is reduced and steps 1 and subsequent steps are repeated.

(Step 15)
When the vibration excess setting value has not been reached, sudden vibration of the saw blade 24, which is a sign of saw blade breakage, is occurring, and the feed rate is excessive. On the other hand, steady vibration is not occurring, and the saw blade 24 can be operated at the upper limit of the rotational speed.
It is determined whether the rotational speed of the saw blade 24 has reached the upper limit value.
(Step 16)
If the upper limit has already been reached, the feed speed is decelerated and steps 1 and subsequent steps are repeated.

(Step 17)
If the upper limit of the rotational speed has not been reached, the rotational speed is accelerated and steps 1 and subsequent steps are repeated.

According to the present invention, a sign of saw blade damage is determined from the measured value of the vibration measurement sensor and the vibration setting value, and based on this determination, the rotational speed of the rotation motor and the rotational speed of the feed motor are determined. By controlling at least one of them, it is possible to maximize the feed rate while avoiding saw blade breakage. Furthermore, control can be performed to optimize the circumferential speed or feed speed based on physical changes such as frame vibration and saw blade positional deviation. Additionally, the operating speed can be automatically adjusted efficiently without the need for experienced technology.
The preferred embodiments of the present invention have been described above. However, the present invention is not limited to the above-described embodiments, and various modifications can be made without departing from the spirit of the present invention.
Further, the present invention is not limited to the combinations shown in the embodiments, but can be implemented by various combinations.

10 Band saw 12 Frame body 13 Upper frame 14 Lower frame 15 Pillar 20 Cutting means 24 Saw blade 26 Wheel 28 Rotation motor 29 Lifting frame 30 Feeding means 32 Feeding motor 33 Ball screw 40 Vibration measurement sensor 50 Saw blade vertical position measurement sensor 51 Saw Blade horizontal position measurement sensor 52 Fixture 60 Judgment section 70 Control section

Claims (5)

A cutting means having an endless saw blade, a pair of wheels around which the saw blade is wound, a rotation motor connected to one of the wheels to drive the rotation, and a feeding motor that moves the cutting means in a cutting direction. In a band saw equipped with a feeding means having
A vibration measurement sensor that detects vibrations generated during cutting,
a saw blade vertical position measurement sensor that detects the height position of the saw blade;
a saw blade horizontal position measurement sensor that detects the horizontal position of the saw blade;
Compare the measurement value of the vibration measurement sensor and the vibration setting value, the measurement value of the saw blade vertical position measurement sensor and the saw blade height change setting value, and the measurement value of the saw blade horizontal position measurement sensor and the saw blade position setting value. a determination unit to
A band saw comprising: a control section that controls at least one of the rotational speed of the rotation motor and the rotational speed of the feed motor based on the determination of the determination section. The band saw according to claim 1,
The band saw is characterized in that the saw blade vertical position measuring sensor is a laser sensor attached to the lifting frame of the cutting means to detect the height position of the saw blade. The band saw according to claim 1,
A band saw characterized in that the saw blade horizontal position measurement sensor is a laser sensor that is attached to the lifting frame of the cutting means to detect the horizontal position of the saw blade. The band saw according to claim 1,
The band saw is characterized in that the vibration measurement sensor is provided at a connection point between a column of the frame main body to which the feeding means is attached and an upper frame. The band saw according to any one of claims 1 to 4,
A determining section determines a sign of saw blade damage from the measured value of the vibration measurement sensor and the vibration setting value, and based on the determination of the determining section, the rotational speed of the rotation motor and the rotational speed of the feed motor are determined. A band saw characterized in that the feed rate is maximized while avoiding damage to the saw blade by controlling at least one side by a control unit.

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