CUTTING MACHINE INCLUDING A PROTECTION PLATE

Abstract

The present invention relates to a cutting machine including a protective plate capable of preventing entry into a cutting area from the outside, avoiding stopping cutting due to unnecessary entry behavior, reliably detecting the entry, stopping operation of the cutting machine, and ensuring safety. At the time of cutting, the protective plate (3) is raised to one side of the cutting table (10) on which at least the functional unit (12) is located so as to be in a state of protection preventing entry into a cutting area (10a) from the outside.Since the boundary can be easily visually identified in the protection state, it is possible to prevent entry into the cutting area (10a) from the outside to avoid stopping the cutting, and to reliably detect the entry such as displacement of the protection plate (3) and the like at the time of entry to stop the cutting and ensure safety.Abstract Figure: Figure 1.

Description

Title of the invention: CUTTING MACHINE INCLUDING A PROTECTIVE PLATE Technical field

[0001] The present invention relates to a cutting machine provided with a protective plate intended to prevent and detect the entry of the cutting machine into a cutting area. DESCRIPTION OF THE STATE OF THE ART

[0002] Traditionally, in a cutting machine, a material to be cut is placed on a cutting table, and a cut is made to cut a target piece from the material to be cut while a cutting blade is moving along a surface of the cutting table. During cutting, it is dangerous for a human body or the like to enter the cutting area where the cutting is being performed. Also known is a cutting machine that avoids danger by stopping the cutting when such an entry is detected (see e.g., patent document 1). This cutting machine uses a light curtain to optically detect the entry. In the example of patent document 1, the light curtain may be used in conjunction with a guard plate that moves up and down at the periphery of the cutting table.In this example, the light curtain is formed to extend to the upper side of the guard plate, entry is prevented by the guard plate, and detection of entry until the cutting machine stops cutting is performed using the light curtain. STATE OF THE ART DOCUMENT PATENT DOCUMENT

[0003] [Patent Document 1] US Patent Publication No. 2022 / 274279 TECHNICAL PROBLEM

[0004] Optical input detection as described in patent document 1 is performed at a boundary of a cutting area where input is prohibited, and is detected when a part of a human body or the like crosses the boundary. However, for example, even a light curtain using visible light is difficult to visually identify in the middle of the optical path. Even in the case of unnecessary input behavior due to negligence or the like, it is not possible to know whether the optical path has been blocked or not unless the boundary is actually crossed, and once the optical path is blocked, cutting is stopped by the input detection even if there is no more input, so that the efficiency of cutting may be reduced. Summary of the invention

[0005] An object of the present invention is to provide a cutting machine including a protective plate capable of preventing entry into a cutting area from the outside, avoiding stopping cutting due to unnecessary entry behavior, reliably detecting entry, stopping operation of the cutting machine, and ensuring safety.

[0006] The present invention provides a cutting machine including a guard plate for preventing entry into a cutting area from the outside for cutting by a cutting blade that moves along a surface of a cutting table approximately rectangular with respect to a material to be cut placed on the cutting table, the cutting machine being characterized in that: the guard plate is provided at least on one side of the cutting table, on a side where an operation is performed, and the cutting machine comprising the guard plate comprises: a switching mechanism configured to switch the guard plate into a guard state in which it is raised to prevent entry into the cutting area at least at the time of cutting, and into an open state in which it allows entry into the cutting area, a detection means configured to detect an external action on the protection plate, and a protective means configured to perform a protective operation including stopping the cutting or slowing the cutting in response to detection of the external action by the detection means.

[0007] Further and optionally, in the present invention, the external action detected by the detection means may be a displacement of the protection plate, and the protection means may perform the protection operation according to a displacement state of the protection plate detected by the detection means.

[0008] Further and optionally, in the present invention, the detection means may detect a movement of the protection plate such as a tilting of the protection plate around a tilting shaft, and the protection means may perform a protection operation, which includes for example stopping cutting, when the detection means detects the tilting in a direction of entry into the cutting area.

[0009] Additionally and optionally, in the present invention, the switching mechanism: moves the protection plate up and down, and switches: in the protection state by moving the protection plate upwards; and in the opening state by moving the protection plate downwards.

[0010] Additionally and optionally, in the present invention, the switching mechanism: tilts the protection plate around a tilting shaft, and switches: in the protected state when the protection plate is raised above the tipping shaft; and in the open state when the protective plate is lowered below the tilting shaft.

[0011] According to the present invention, at the time of cutting, the protective plate is raised at least on one side of the cutting table on which at least the operation is performed, so as to be in a protective state preventing entry into the cutting area from the outside. Since the boundary can be easily visually identified in the protective state, it is possible to prevent entry into the cutting area from the outside to avoid stopping the cutting, and to reliably detect the entry as an external action on the protective plate at the time of entry to stop the cutting and ensure safety.

[0012] Furthermore, according to the present invention, the detection of the external action on the protection plate is detected by the movement of the protection plate, and it is possible to avoid a decrease in cutting efficiency due to stopping of cutting or the like which occurs when the protection operation is performed only by the detection of contact.

[0013] According to the present invention, it is possible to detect the displacement of the protective plate as the tilting, and the entry into the cutting area and the other displacement can be distinguished by the direction of the tilting. With respect to the entry into the cutting area, safety can be reliably ensured by performing the protection operation including stopping the cutting.

[0014] Furthermore, according to the present invention, since the protection plate is switched between the protection state and the opening state by moving up and down, a space required for switching between the protection state and the opening state can be reduced.

[0015] According to the present invention, since the protective plate is switched between the protective state and the opening state by tilting, a displacement of the protective plate can be easily detected by the tilting. Brief description of the drawings

[0016] [Fig.l] is a perspective view illustrating a schematic configuration of a cutting machine 1 including a protective plate 3 according to a first example of the present invention; [Fig.2]: Figures 2(a) and 2(b) are partial right-hand views illustrating an operation of a protection plate 3 of [Fig.l]; [Fig.3] is a perspective view illustrating a configuration of a part that detects a tilting of the protection plate 3 of [Fig.l]; [Fig.4] is a plan view illustrating a configuration of a portion that detects a tilting of the protective plate 3 of [Fig.l]; [Fig.5] is a process diagram illustrating a protection operation of the cutting machine 1 including the protection plate 3 of [Fig.l]; [Fig.6] is a partial perspective view illustrating a schematic configuration of a cutting machine 5 including a protection plate 7 according to a second example of the present invention; [Fig.7]: Figures 7(a) to 7(c) are partial right views illustrating an operation of a protection plate 7 of [Fig.6]; [Fig.8] is a partial plan view illustrating a configuration for moving up and down the protection plate 7 of [Fig.6]; [Fig.9] is a partial cross-sectional view illustrating a configuration for moving up and down the protection plate 7 of [Fig.6] as viewed from a direction of a cutting line AA; and [Fig. 10] is a partial right-hand view illustrating a configuration in which input detection is performed by tilting at an upper side of the protective plate 7 of [Fig. 6].

[0017] DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT

[0018] Hereinafter, [Fig. 1] to [Fig. 5] illustrate a configuration and an operation relating to a cutting machine 1 including a protective plate 3 according to a first example of the present invention. [Fig. 6] to [Fig. 10] illustrate a configuration and an operation relating to a cutting machine 5 including a protective plate 7 according to a second example of the present invention. Furthermore, for ease of explanation, parts not depicted in the drawings to be described may be designated by reference numerals depicted in other drawings. First example

[0019] [Fig.l] illustrates a schematic configuration of a cutting machine 1 including a protective plate 3 according to a first example of the present invention. The cutting machine 1 is provided with a cutting table 10 having approximately a rectangular shape in plan view, and a material to be cut 2 such as a fabric or an industrial material is placed on the cutting table 10 and cut using a blade cutting included in a cutting head 11. The cutting head 11 moves along the surface of the cutting table 10, and a cutting area 10a is thus formed on the cutting table 10. In the cutting table 10, one of the long sides is the front side, one of the short sides is the inlet side, and the other of the short sides is the outlet side. The cutting table 10 may be configured to function as a conveyor that transports the material to be cut 2 in the direction of the long sides and transports the material to be cut 2 from the inlet side and transports the material to be cut 2 to the outlet side after cutting. A functional unit 12 for operating the cutting machine 1 is often installed at the front side and the outlet side. The operation of the cutting machine 1 in response to the operation of the functional unit 12 is controlled by a control unit 13 indicated by "CONTROL" in the figure..

[0020] In the first example, the protective plate 3 that prevents entry of the human body into the cutting area 10a from the outside is located on the front side where the operation of the functional unit 12 is performed and on the rear side opposite the front side. The protective plate 3 is preferably made of a transparent material such as an acrylic resin and may be located at least on the side where the operation is performed. The protective plate 3 is provided with covers 3a at two side ends to prevent entry in that direction. An operation bar 3b is located at the upper part of the protective plate 3, and the protective plate 3 can be manually switched between a protection state and an opening state by tilting by a switching mechanism 30.This tilting is detected by a detection unit 31 serving as a detection means, and the detection result is inputted into a protection means 32, indicated by “PROTECT” in the figure. The protection means 32 may be located in a part of the functional unit 12 or the control unit 13. The detection unit 31 detects the tilting of the protection plate 3 around a center line 33a of a tilting shaft 33. The tilting shaft 33 is located at a height close to the surface of the cutting table 10 in a direction parallel to the long side of the cutting table 10. The height of the protection plate 3 in the protection state is preferably greater than the chest height of the operator.

[0021] [Fig.2] illustrates an operation of the guard plate 3 of [Fig.l]. [Fig.2](a) illustrates a guard state in which it is raised to prevent entry into the cutting area 10a at least at the time of cutting. The switching mechanism 30 performs a function of fixing the guard plate 3 in the guard state so that the guard state can be maintained. [Fig.2](b) shows the guard plate 3 being tilted counterclockwise relative to the tilt shaft 33 from the guard state indicated by the solid line to the state opening indicated by the dotted line, and tilted clockwise in the entry detection state indicated by the broken line. In the entry detection state, the guard plate 3 is tilted in the direction of the cutting area 10a by contacting the upper part of the guard plate 3 at the time of entry from the upper side of the guard plate 3.

[0022] [Fig. 3] and [Fig. 4] illustrate a configuration of a part that detects the protection state from the tilting of the protection plate 3 and that serves as a detection unit 31 in [Fig. 1]. Proximity sensors 31a and 31b are attached to a fixing member 31c and arranged on the cutting table 10 side, and detect the detection elements 34a and 34b located on the tilting shaft 33. In the illustrated state, corresponding to the protection state, the proximity sensors 31a and 31b are both turned off, i.e., they do not detect the detection elements 34a and 34b. When the guard plate 3 continues to swing toward the cutting area 10a around the swing shaft 33, the proximity sensor 31a turns on and the proximity sensor 31b remains off, thereby entering an entry detection state.When it is switched to a side away from the cutting area 10a from the state shown in the drawing, the proximity sensor 31a remains off, the proximity sensor 31b turns on, and the state is not detected as the protection state.

[0023] [Fig.5] illustrates a protection operation by the protection means 32 of [Fig. 1]. Upon power-up in step a1, whether there is a cutting start command is determined in step a2, and the process waits until there is a cutting start command. When the cutting start command is given by the functional unit 12, the process proceeds to step a3, and whether the protection plate 3 is in the protection state is determined based on the output of the detection unit 31. When not in the protection state, the process returns to step a2 and waits for the cutting start command again. When it is determined that the process is in the protection state in step a3, cutting is started in step a4. During cutting, it is determined in step a5 whether or not there is an entry detection.When it is determined that there is an entry detection, cutting is stopped in step a6, and the cutting machine 1 is stopped by turning off the power in step a7. Cutting can be performed at low speed without being stopped. When it is determined in step a5 that there is no entry detection, it is determined in step a8 whether the process is in the protection state or not. When it is determined that the process is in the protection state, the process returns to step a5 and cutting continues. When it is determined in step a8 that the process is not in the protection state, cutting is interrupted in step a9. It is possible to reduce the cutting speed instead of interrupting cutting. Then, in step a10, it is determined whether there is an entry detection or not. The process proceeds to . step a6 if there is input detection and the process proceeds to step a1 1 if there is no input detection. In step a1 1, it is determined whether or not there is the protection state. If the process is not in the protection state, the process returns to step a10, and if the process is in the protection state, it is determined in step a12 whether or not to resume cutting. When it is determined that cutting should be resumed in step a12, the process returns to step a5, and when it is determined that cutting should not be resumed, the process returns to step a10.

[0024] As described above, in the first example, entry into the cutting area 10a is detected by the tilting of the protective plate 3, but contact with the upper end portion of the protective plate 3 may be detected as an external action on the protective plate 3 and regarded as the entry detection. The contact may be detected, for example, by a resistance method in which a resistance film is attached to the surface of the protective plate 3, and the detection is performed from a change in the resistance value, by a capacitance method, or the like. Furthermore, although the manually switched switching mechanism 30 is used, automatic switching may be performed by motorized drive or the like. Second example

[0025] [Fig.6] partly illustrates a schematic configuration of a cutting machine 5 including a protection plate 7 according to a second example of the present invention. The configuration of the cutting machine 5 of the second example is basically similar to that of the cutting machine 1 of the first example, including the configuration corresponding to the functional unit 12, the control unit 13 and the protection means 32 (not shown), a cutting table 50 having a roughly rectangular shape in top view being provided and the material to be cut 2 being placed on the cutting table 50 and cut by the cutting head 51. A cutting area 50a is formed on the cutting table 50.Although the guard plate 7 is located to prevent entry into the cutting area 50a from the outside, similarly to the guard plate 3 of the first example, since the opening and closing by a switching mechanism 70 is of an up-and-down movable type, the space required for switching the guard plate 7 between the protection state and the opening state can be reduced. The cutting machine 5 also includes a functional unit similar to that of the cutting machine 1 of the first example on the front side, and the guard plate 7 is located at least on the front side. A hood 7a is located on both sides of the guard plate 7, and a cover 7b is located on the bottom side.

[0026] Figures 7(a) to 7(c) of [Fig.7] illustrate an operation of the protective plate 7 by the switching mechanism 70 of [Fig.6]. [Fig.7](a) illustrates a state of protection in which the protection plate 7 is moved upward, [Fig. 7](b) illustrates an opening state in which the protection plate 7 is moved downward, and [Fig. 7](c) illustrates an entry detection state from the protection state. The switching mechanism 70 includes a cylinder 70a that drives the protection plate 7 to move up and down. Although the movement of the protection plate 7 is detected as tilting in the same way as the protection plate 3 of the first example, the detection unit 71 does not directly detect the tilting of the protection plate 7 but detects the tilting relative to a guide rail 72 driven by the cylinder 70a. The guide rail 72 is fixed to the side of the cutting table 50 by means of a tilting member 73a so as to be tiltable around a tilting shaft 73.In the input detection state, the protection plate 7 is tilted in the direction of the cutting area 50a side, while in the protection state, it is close to the vertical position. Such tilting is detected by the detection unit 71 in the same manner as the detection unit 31 of the first example. It should be noted that, for example, a case where the protection plate 7 that moves up and down is pushed downward can be detected as the movement of the protection plate 7, and the protection operation can be performed.

[0027] [Fig.8] and [Fig.9] illustrate a configuration in which the guard plate 7 of [Fig.6] is moved up and down, and [Fig.9] is a sectional view along a cutting line AA in [Fig.8]. The cylinder 70a is fixed to the side of the cutting table 50 by means of a fixing plate 72a. The guide rail 72 can be tilted around the tilting shaft 73 via the tilting member 73a together with the fixing plate 72a. A roller 74 fixed to the fixing plate 72a by means of a screw 74a is located between the guide rail 72 and the fixing plate 72a. The direction of the tilting shaft 73 is the direction of the long side of the cutting table 50.

[0028] [Fig. 10] illustrates a modified example of the second example. In this modified example, the detection unit 75 located on the upper part of the protection plate 7 detects the tilting accompanying the entry into the cutting area 50a. The detection unit 75 comprises a detection plate 75a and a tilting shaft 75b. Similar to the second example, the entry detection is performed as the tilting of the tilting shaft 75b toward the side of the cutting area 50a. It should be noted that the protection operation in the second example is performed in the same manner as in the first example, including the present modified example. The contact with the protection plate 7 can be detected by a resistance film.

Claims

Claims

1. A cutting machine (1, 5) including a guard plate (3, 7) for preventing entry into a cutting area (10a, 50a) from the outside for cutting by a cutting blade that moves along a surface of a cutting table (10, 50) approximately rectangular with respect to a material to be cut (2) placed on the cutting table (10, 50); the cutting machine being characterized in that: the guard plate (3, 7) is provided at least on one side of the cutting table (10, 50), on a side where an operation is performed;and the cutting machine (1, 5) including the guard plate (3, 7) comprises: a switching mechanism (30, 70) configured to switch the guard plate (3, 7) into a protection state in which it is raised to prevent entry into the cutting area (10a, 50a) at least at the time of cutting, and into an opening state in which it allows entry into the cutting area (10a, 50a); a detection means configured to detect an external action on the guard plate (3, 7); and a protection means (32) configured to perform a protection operation including stopping or slowing down the cutting in response to the detection of the external action by the detection means.;

2. A cutting machine (1, 5) including the protective plate (3, 7) according to claim 1, characterized in that: the external action detected by the detection means is a displacement of the protective plate (3, 7), and the protection means (32) performs the protection operation according to a displacement state of the protective plate (3, 7) detected by the detection means.

3. A cutting machine (1, 5) including the guard plate (3, 7) according to claim 2, characterized in that: the detecting means detects the movement of the guard plate (3, 7) as a tilting of the guard plate (3, 7) around a tilting shaft (33, 73), and the protection means (32) performs the protection operation when the detection means detects a tilting in an entry direction into the cutting area (10a, 50a).

4. A cutting machine (5) including the protective plate (7) according to any one of claims 1 to 3, characterized in that: the switching mechanism (70): moves the protective plate (7) up and down, and switches: into the protection state by moving the protective plate upward; and into the opening state by moving the protective plate downward.

5. A cutting machine (1) including the guard plate (3) according to any one of claims 1 to 3, characterized in that: the switching mechanism (30): tilts the guard plate (3) around a tilting shaft (33), and switches: into the guard state when the guard plate (3) is raised above the tilting shaft (33); and into the open state when the guard plate (3) is lowered below the tilting shaft (33).

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