Cutting device

Abstract

To improve safety at the time of working by suppressing the lowering of the working accuracy of a member to be cut and the scattering of the member to be cut in a cutting device.SOLUTION: The cutting device includes a support configured to support a workpiece, a cutting tool supported by the support so as to be movable toward and away from the support and configured to cut the workpiece with a cutting blade, an electric motor configured to operate the cutting blade, a power supply circuit configured to supply electric power to the electric motor, a detector configured to detect a length of the workpiece supported by the support, and an interlock circuit configured to interrupt the supply of electric power from the power supply circuit to the electric motor based on a detection result of the detector.SELECTED DRAWING: Figure 3

Description

[Technical Field]

[0001] The present disclosure relates to a cutting device. [Background technology]

[0002] A band saw as a cutting device includes a table that supports the workpiece to be cut and a cutting tool that can be raised and lowered relative to the table. The cutting tool has an endless saw blade rotatably supported by a pair of saw wheels and a drive motor that drives and rotates the saw wheels. The drive motor drives and rotates the saw wheels, moving the saw blade, which cuts the workpiece supported on the table.

[0003] Some cutting devices are provided with an interlock device that stops operation in an emergency, taking into consideration the safety of the operator. An example of a conventional interlock device is described in Patent Document 1. [Prior art documents] [Patent documents]

[0004] [Patent Document 1] Japanese Patent Publication No. 2022-148152 Summary of the Invention [Problem to be solved by the invention]

[0005] For example, when the workpiece is long, one longitudinal end of the workpiece is supported by a vice device on a table, and the other end is cut by the saw blade of a cutting tool. In this case, when the workpiece is short, the support of one end of the workpiece by the vice device may be insufficient, and when the other end is cut by the saw blade of the cutting tool, the workpiece on the table may shift due to processing stress, resulting in a decrease in processing accuracy or the workpiece may be scattered.

[0006] The present disclosure is intended to solve the above-mentioned problems, and aims to provide a cutting device that improves safety during processing by suppressing a decrease in processing accuracy of the material to be cut and scattering of the material to be cut. [Means for solving the problem]

[0007] In order to achieve the above-mentioned object, the cutting device of the present disclosure comprises a support part that supports the material to be cut, a cutting tool that is supported so as to be able to move towards and away from the support part and that can cut the material to be cut with a cutting blade, an electric motor that operates the cutting blade, a power supply circuit that can supply power to the electric motor, a detection part that detects the length of the material to be cut supported by the support part, and an interlock circuit that cuts off the supply of power to the electric motor by the power supply circuit depending on the detection result of the detection part. [Effects of the Invention]

[0008] According to the cutting device of the present disclosure, it is possible to improve safety during processing by suppressing a decrease in processing accuracy of the material to be cut and scattering of the material to be cut. [Brief explanation of the drawings]

[0009] [Figure 1] FIG. 1 is a front view showing the cutting device of this embodiment. [Figure 2] FIG. 2 is a plan view showing the cutting device. [Figure 3] FIG. 3 is a schematic diagram showing the power supply circuit of the cutting device. DETAILED DESCRIPTION OF THE INVENTION

[0010] Preferred embodiments of the present disclosure will be described in detail below with reference to the drawings. Note that the present disclosure is not limited to these embodiments, and when there are multiple embodiments, the present disclosure also includes configurations that combine the embodiments. Furthermore, the components in the embodiments include those that can be easily imagined by a person skilled in the art, those that are substantially identical, and those that are within the so-called equivalent range.

[0011] <Cutting device configuration> FIG. 1 is a front view showing the cutting device of this embodiment, and FIG. 2 is a plan view showing the cutting device.

[0012] As shown in Figures 1 and 2, the cutting device 10 of this embodiment is a band saw. However, the cutting device is not limited to a band saw. Any device capable of cutting a workpiece may be used. The cutting device 10 comprises a table (support) 11 and a cutting tool 12. The table 11 is capable of supporting a workpiece 100 to be cut. The cutting tool 12 is capable of moving up and down by rotating relative to the table 11. The cutting tool 12 is capable of cutting the workpiece 100 supported by the table 11.

[0013] In the following explanation, the longitudinal direction of table 11 (the left-right direction in Figs. 1 and 2) is defined as the X direction, the width direction of table 11 (the up-down direction in Fig. 2) is defined as the Y direction, and the height direction of table 11 (the up-down direction in Fig. 1) is defined as the X direction. The X direction, Y direction, and Z direction are perpendicular to each other.

[0014] A vice 21 is disposed on the upper part of the table 11. The table 11 is provided with a first guide groove 22 and a second guide groove 23. The first guide groove 22 and the second guide groove 23 are provided to penetrate the table 11 in the vertical direction (Z direction). The first guide groove 22 is provided along the longitudinal direction (X direction) of the table 11. The second guide groove 23 is provided at a predetermined inclination angle with respect to the longitudinal direction (X direction) of the table 11. The first guide groove 22 and the second guide groove 23 are provided so as to approach each other from one side (the left side in FIG. 2) to the other side (the right side in FIG. 2). However, the second guide groove 23 may be provided parallel to the first guide groove 22.

[0015] The vise 21 has a first support plate 24 and a second support plate 25. The first support plate 24 is placed on the upper surface of the table 11 and is supported so as to be movable along the first guide groove 22 and the second guide groove 23. The second support plate 25 is placed on the upper surface of the table 11 and is supported so as to be movable along the first guide groove 22 and the second guide groove 23. The first support plate 24 can be fixed to the upper surface of the table 11 by a fixing member (e.g., a bolt) 26. The second support plate 25 can be fixed to the upper surface of the table 11 by a fixing member (e.g., a bolt) 27.

[0016] The first support plate 24 and the second support plate 25 are arranged opposite each other on the upper surface of the table 11. The first support plate 24 and the second support plate 25 can support the material to be cut 100 by sandwiching it between them. The material to be cut 100 is a long material. The material to be cut 100 is placed between the first support plate 24 and the second support plate 25 along a direction (Y direction) that intersects with the direction of the first guide groove 22. The first support plate 24 and the second support plate 25 are fixed to predetermined positions on the table 11 by fixing members 26 and 27, thereby sandwiching the material to be cut 100.

[0017] The cutting tool 12 has a housing 31, an electric motor 32, a saw blade (cutting blade) 33, and a pair of saw wheels 34 and 35.

[0018] The housing 31 has an elongated semicircular shape when viewed from the front, and is provided with a cutout 41. The housing 31 is arranged along the longitudinal direction (X direction) of the table 11, and a support shaft 42 at one end of the longitudinal direction is rotatably supported by a bearing 43 provided on the table 11. That is, the housing 31 is rotatable about a rotation axis O along the Y direction by the support shaft 42 and the bearing 43. The housing 31 is movable (rotatable) between a cutting position where it rotates downward to cut the workpiece 100 with the saw blade 33, and a retracted position where it rotates upward to move the saw blade 33 away from the workpiece 100.

[0019] The pair of saw wheels 34, 35 are arranged inside the housing 31 at one end and the other end in the longitudinal direction. The saw wheel 34 is rotatably supported by a support shaft (not shown) along the Y direction at one end of the housing 31. The saw wheel 35 is rotatably supported by a support shaft (not shown) along the Y direction at the other end of the housing 31. The saw blade 33 is an endless, annular metal cutting blade that is wound around the pair of saw wheels 34, 35. The saw blade 33 moves as the saw wheels 34, 35 rotate. The electric motor 32 is provided in the housing 31. The electric motor 32 may have a reducer. An output shaft 44 of the electric motor 32 is connected to the support shaft of the saw wheel 34.

[0020] When the electric motor 32 is driven, the drive torque is transmitted to the saw wheel 34 via the output shaft 44, and the saw wheel 34 is driven to rotate. An endless saw blade 33 is wound around the pair of saw wheels 34, 35, and the rotational force of the saw wheel 34 is transmitted to the saw blade 33, and the saw blade 33 is supported by the pair of saw wheels 34, 35 and can move.

[0021] The cutting blade is not limited to the endless band-shaped saw blade 33 , but may be a rotary blade having a disk shape, and may be rotatable by the electric motor 32 .

[0022] <Power circuit> FIG. 3 is a schematic diagram showing the power supply circuit of the cutting device.

[0023] As shown in Fig. 3, the power supply circuit 50 of the cutting device 10 can supply power to the electric motor 32. The power supply circuit 50 has a power supply unit 51 and a switch 52. In the power supply circuit 50, the electric motor 32, the power supply unit 51, and the switch 52 are connected in series. Therefore, when an operator turns the switch 52 ON, power from the power supply unit 51 is supplied to the electric motor 32, and the electric motor 32 operates. On the other hand, when the operator turns the switch 52 OFF, the supply of power from the power supply unit 51 to the electric motor 32 is stopped, and the operation of the electric motor 32 is stopped.

[0024] As shown in FIGS. 1 to 3, the cutting device 10 includes a detection unit 53 and an interlock circuit 54.

[0025] The detection unit 53 detects the length of the workpiece 100 supported by the vice 21 of the table 11. The detection unit 53 is a non-contact sensor. A photoelectric sensor is suitable as a non-contact sensor, but the non-contact sensor is not limited to a photoelectric sensor and may be an ultrasonic sensor or the like. The detection unit 53 may also be a contact sensor such as a switch.

[0026] The workpiece 100 is a long object, and is supported along the Y direction by the vice 21 of the table 11. When the workpiece 100 is supported by the table 11, one end of the workpiece 100 in the longitudinal direction is a cutting end 101 that is cut by the saw blade 33, and the other end of the workpiece 100 in the longitudinal direction is a supported end 102 that is supported by the vice 21 of the table 11. The detection unit 53 is capable of detecting the supported end 102 of the workpiece 100.

[0027] That is, the first support plate 24 and the second support plate 25 of the vice 21 are placed on the upper surface of the table 11, are supported so as to be freely movable along the first guide groove 22 and the second guide groove 23, and can be fixed by the fixing members 26, 27. The detection unit 53 is disposed below the table 11 and can detect the supported end 102 of the workpiece 100 through the second guide groove 23. That is, the detection unit 53 is disposed on the vice 21 on the opposite side from the saw blade 33 of the midpoint in the Y direction of the first support plate 24 and the second support plate 25 that clamp the workpiece 100.

[0028] However, the mounting position of the detection unit 53 is not limited to the table 11, and may be the first support plate 24 or the second support plate 25 of the vice 21. Furthermore, the detection unit 53 may be disposed above the support end 102 of the workpiece 100 via a bracket (not shown) on the table 11.

[0029] The interlock circuit 54 is connected in series with the electric motor 32, power supply unit 51, and switch 52 that constitute the power supply circuit 50. The detection unit 53 is connected to the interlock circuit 54, and the detection result of the detection unit 53 is input to the interlock circuit 54. The interlock circuit 54 cuts off the supply of power from the power supply circuit 50 to the electric motor 32 in accordance with the detection result of the detection unit 53.

[0030] Specifically, when the detector 53 detects the supporting end 102 of the workpiece 100, the interlock circuit 54 enables the power supply circuit 50 to supply power to the electric motor 32. On the other hand, when the detector 53 does not detect the supporting end 102 of the workpiece 100, the interlock circuit 54 enables the power supply circuit 50 to cut off the supply of power to the electric motor 32.

[0031] <Cutting device operation> As shown in Figures 1 to 3, the worker places the workpiece 100 between the first support plate 24 and the second support plate 25 of the table 11 along the Y direction. For example, the worker moves the second support plate 25 along the first guide groove 22 and the second guide groove 23 and fixes it in a predetermined position with the fixing member 27. The worker moves the first support plate 24 along the first guide groove 22 and the second guide groove 23 toward the second support plate 25 and fixes it with the fixing member 26 at a position where the workpiece 100 is sandwiched between the first support plate 24 and the second support plate 25.

[0032] The operator positions the cutting tool 12 at a retracted position above the table 11 and turns on the switch 52. At this time, the detector 53 attempts to detect the supported end 102 of the workpiece 100 from below the table 11 through the second guide groove 23. If the workpiece 100 is an elongated object having a predetermined length and is clamped over almost the entire area in the Y direction between the first support plate 24 and the second support plate 25, the detector 53 can detect the supported end 102 of the workpiece 100. The detector 53 outputs to the interlock circuit 54 that it has detected the supported end 102 of the workpiece 100, i.e., that the workpiece 100 is properly supported in the vise. As a result, the interlock circuit 54 places the power supply circuit 50 in a conductive state, causing the power supply 51 to supply power to the electric motor 32, which then rotates.

[0033] When the electric motor 32 is driven to rotate, the drive torque is transmitted to the saw wheel 34 via the output shaft 44, causing the saw wheel 34 to rotate. The endless saw blade 33, which is wound around the saw wheels 34 and 35, then moves. The operator rotates the cutting tool 12 to lower it and move it to the cutting position. The saw blade 33 of the cutting tool 12 then comes into contact with the cutting end 101 of the workpiece 100, allowing the workpiece 100 to be cut.

[0034] On the other hand, if the workpiece 100 is a short object that does not have the specified length, the first support plate 24 and the second support plate 25 cannot clamp the workpiece 100 over almost the entire area in the Y direction. As a result, the detection unit 53 cannot detect the supported end 102 of the workpiece 100. The detection unit 53 outputs to the interlock circuit 54 that it has not detected the supported end 102 of the workpiece 100, that is, that the workpiece 100 is not properly supported in the vise. Therefore, the interlock circuit 54 shuts off the power supply circuit 50, the power supply unit 51 does not supply power to the electric motor 32, and the electric motor 32 does not rotate.

[0035] If the workpiece 100 is short, the first support plate 24 and the second support plate 25 of the vice 21 may not be able to clamp the workpiece 100 with sufficient support force. If the workpiece 100 is cut with the cutting tool 12 in this state, the workpiece 100 may be displaced on the table 11 due to processing stress, resulting in reduced processing accuracy, or the workpiece 100 may become unsupported and scattered. In this embodiment, the support state of the workpiece 100 by the vice 21 is determined based on whether the detector 53 detects the support end 102 of the workpiece 100. If the vice 21 is not sufficiently supporting the workpiece 100, the interlock circuit 54 cuts off the power supply to the electric motor 32. This prevents the workpiece 100 from being cut with sufficient precision or scattered.

[0036] [Effects of this embodiment] The cutting device of the first embodiment comprises a table (support part) 11 that supports the workpiece 100, a cutting tool 12 that is supported so as to be able to move towards and away from the table 11 and that can cut the workpiece 100 with a saw blade (cutting blade) 33, an electric motor 32 that operates the saw blade 33, a power supply circuit 50 that can supply power to the electric motor 32, a detection part 53 that detects the length of the workpiece 100 supported on the table 11, and an interlock circuit 54 that cuts off the supply of power from the power supply circuit 50 to the electric motor 32 depending on the detection result of the detection part 53.

[0037] According to the cutting device of the first aspect, the detection unit 53 detects the state of support of the workpiece 100 by the table 11, and when the workpiece 100 is not sufficiently supported by the table 11, the interlock circuit 54 cuts off the power supply to the electric motor 32. This makes it possible to prevent a decrease in the processing accuracy of the workpiece 100 and scattering of the workpiece 100, thereby improving safety during processing.

[0038] The cutting device according to the second aspect is the cutting device according to the first aspect, and further includes an interlock circuit 54 that cuts off the supply of power from the power supply circuit 50 to the electric motor 32 when the detection unit 53 does not detect the workpiece 100. This allows the electric motor 32 to be stopped appropriately when the table 11 is not sufficiently supporting the workpiece 100.

[0039] The cutting device according to the third aspect is the cutting device according to the first or second aspect, with the additional feature that the detector 53 is a non-contact sensor, which allows the detector 53 to operate without interfering with the operation of the cutting tool 12, thereby improving operability.

[0040] The cutting device according to the fourth aspect is the cutting device according to any one of the first to third aspects, and further, the workpiece 100 is a long member, one end side in the longitudinal direction is a cut end 101 cut by the saw blade 33, and the other end side in the longitudinal direction is a supported end 102 supported by the table 11, and the detection unit 53 is capable of detecting the supported end 102. This allows the detection unit 53 to appropriately detect the state in which the workpiece 100 is supported by the table 11.

[0041] The cutting device according to the fifth aspect is the cutting device according to any one of the first to fourth aspects, further comprising a table 11 and a vice 21 that is supported movably along guide grooves (groove portions) 22, 23 provided on the table 11 and that secures the workpiece 100 to the table 11, and the detection unit 53 is disposed below the table 11 and is capable of detecting the support end portion 102 through the guide grooves 22, 23. This allows the detection unit 53 to be disposed in an appropriate position that does not interfere with the operation of the cutting tool 12. [Explanation of symbols]

[0042] 10 Cutting device 11 Table (support part) 12 Cutting tools 21 Vise 22 First guide groove 23 Second guide groove 24 1st support plate 25 Second support plate 26,27 Fixing member 31 Housing 32 Electric motor 33 Saw blade (cutting blade) 34,35 Saw wheel 41 Notch 42 Support shaft 43 Bearing section 44 Output shaft 50 Power circuit 51 Power supply section 52 Switch 53 Detection unit 54 Interlock Circuit 100 Part to be cut 101 Cut end 102 Support end

Claims

1. a support portion that supports the workpiece; a cutting tool that is supported so as to be movable toward and away from the support part and that is capable of cutting the workpiece with a cutting blade; an electric motor for operating the cutting blade; a power supply circuit capable of supplying power to the electric motor; a detection unit that detects the length of the workpiece supported by the support unit; an interlock circuit that cuts off the supply of power from the power supply circuit to the electric motor in response to the detection result of the detection unit; A cutting device comprising:

2. the interlock circuit cuts off the supply of power from the power supply circuit to the electric motor when the detection unit does not detect the workpiece to be cut.

2. The cutting device of claim 1.

3. The detection unit is a non-contact sensor.

2. The cutting device of claim 1.

4. the member to be cut is an elongated member, one end side in the longitudinal direction is a cut end to be cut by the cutting blade, and the other end side in the longitudinal direction is a supported end supported by the support part, and the detection part is capable of detecting the supported end.

2. The cutting device of claim 1.

5. The support unit has a table and a vice that is supported movably along a groove provided on the table and fixes the workpiece to the table, and the detection unit is disposed below the table and is capable of detecting the support end through the groove.

5. The cutting device of claim 4.

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