Cutting machine and cutting method

Abstract

To provide a cutting machine that can achieve high dust collection efficiency regardless of the size of cutting chips.SOLUTION: A cutting machine 10 includes: a cutting device for cutting a workpiece 1; a machining chamber 21 that houses the cutting device; a dust collection port 61 that is open in the machining chamber 21 and is connected to a dust collector; and a throttle mechanism 90 that is configured to be able to change the opening area of the dust collection port 61.SELECTED DRAWING: Figure 9

Description

Technical Field

[0001] The present invention relates to a cutting machine and a cutting method.

Background Art

[0002] A cutting machine for producing, for example, dental molded products by cutting a workpiece has been conventionally known. For example, Patent Document 1 discloses a cutting machine including a box-shaped case, a front cover, and a cutting device housed in the internal space of the case for machining a workpiece. A dust collecting device is connected to the cutting machine described in Patent Document 1. The dust collecting device communicates with the internal space of the case and collects cutting chips generated by cutting.

Prior Art Documents

Patent Documents

[0003]

Patent Document 1

Summary of the Invention

Problems to be Solved by the Invention

[0004] The size of cutting chips generated by cutting can be various depending on, for example, the material of the workpiece and cutting conditions. When collecting cutting chips in the processing chamber by a dust collector connected to the processing chamber, the efficient dust collection conditions may differ depending on the size of the cutting chips. According to the findings of the inventor of the present application, in the case of fine cutting chips, the dust collection efficiency tends to be better when the air volume at the dust collection port opening to the processing chamber is larger. On the other hand, in the case of large cutting chips, the dust collection efficiency tends to be better when the wind speed at the dust collection port is larger. However, in a dust collector, when the air volume at the dust collection port is increased, the wind speed decreases, and when the wind speed at the dust collection port is increased, the air volume tends to decrease. Therefore, it has been difficult to obtain dust collection conditions that can achieve high dust collection efficiency for cutting chips of various sizes.

[0005] This invention has been made in view of the above problems, and its objective is to provide a cutting machine that can achieve high dust collection efficiency regardless of the size of the cutting chips. It also aims to provide a cutting method for a workpiece that can achieve high dust collection efficiency regardless of the size of the cutting chips. [Means for solving the problem]

[0006] The cutting machine disclosed herein comprises a cutting device for cutting a workpiece, a processing chamber in which the cutting device is housed, a dust collection port opening into the processing chamber and connected to a dust collector, and a throttling mechanism configured to change the opening area of ​​the dust collection port.

[0007] According to the above cutting machine, by adjusting the opening area of ​​the dust collection port using a throttling mechanism, suitable dust collection conditions can be obtained according to the size of the cutting chips. For example, when the cutting chips are fine, the opening area of ​​the dust collection port can be increased by the throttling mechanism, thereby increasing the airflow at the dust collection port. This allows for efficient collection of fine cutting chips. Also, for example, when the cutting chips are large, the opening area of ​​the dust collection port can be reduced by the throttling mechanism, thereby increasing the airflow at the dust collection port. This allows for efficient collection of large cutting chips. According to the above cutting machine, high dust collection efficiency can be achieved regardless of the size of the cutting chips by adjusting the opening area of ​​the dust collection port.

[0008] Furthermore, the method for cutting a workpiece disclosed herein includes cutting the workpiece and collecting the cutting chips from the workpiece using a dust collector equipped with a dust collection port for drawing in air, wherein the opening area of ​​the dust collection port is changed according to the size or shape of the cutting chips. With this cutting method, as with the cutting machine described above, high dust collection efficiency can be achieved regardless of the size of the cutting chips. [Brief explanation of the drawing]

[0009] [Figure 1] This is a perspective view of a cutting machine according to the first embodiment. [Figure 2]This is a plan view of the workpiece and the adapter. [Figure 3] This is a perspective view showing the inside of the processing chamber, with the aperture cover not yet installed. [Figure 4] This is a longitudinal cross-section passing through the machining chamber of a cutting machine. [Figure 5] This is a block diagram of a cutting machine. [Figure 6] This figure shows an example of a cover selection table. [Figure 7] This is a perspective view of the aperture cover. [Figure 8] This is a longitudinal cross-sectional view showing the diaphragm cover attached to the dust collection port. [Figure 9] This is a perspective view showing the inside of the processing chamber, with a diaphragm cover attached to the dust collection port. [Figure 10] This is a schematic partially broken perspective view showing the machining chamber of a cutting machine according to the second embodiment. [Figure 11] This is a block diagram of a cutting machine according to the second embodiment. [Figure 12] This figure shows an example of an aperture selection table. [Figure 13] This is a schematic longitudinal cross-sectional view of the machining chamber showing the rotational position of the movable bottom wall. [Modes for carrying out the invention]

[0010] A cutting machine according to one embodiment will be described below with reference to the drawings. It should be noted that the embodiment described herein is not intended to limit the present invention. Furthermore, the same reference numerals are used for components and parts that perform the same function, and redundant explanations are omitted or simplified as appropriate.

[0011] [First Embodiment] FIG. 1 is a perspective view of a cutting machine 10 according to an embodiment. In the following description, when the cutting machine 10 is viewed from the front, the direction away from the cutting machine 10 is defined as the front, and the direction approaching the cutting machine 10 is defined as the rear. The left, right, upper, and lower directions refer to the left, right, upper, and lower directions when the cutting machine 10 is viewed from the front, respectively. In the drawings, the reference signs F, Rr, L, R, U, and D denote the front, rear, left, right, upper, and lower directions, respectively.

[0012] The cutting machine 10 according to the present embodiment is a cutting machine that cuts a disk-shaped workpiece held by an adapter. FIG. 2 is a plan view of the workpiece 1 and the adapter 5. Here, the cutting machine 10 cuts the workpiece 1 to produce dental molded products, such as crowns, bridges, copings, inlays, onlays, veneers, custom abutments, etc., and artificial teeth, denture bases, etc. The cutting machine 10 according to the present embodiment is a dry cutting machine that does not use coolant.

[0013] The workpiece 1 is made of, for example, resins such as ABS, PMMA (polymethyl methacrylate resin), dental resin, wax, zirconia, gypsum, etc. The material of the workpiece 1 may also be made of, for example, resins such as PEEK, glass fiber reinforced resin, hybrid resin, etc., ceramic materials such as glass ceramics, metal materials such as cobalt chromium sintered metal, etc. The material of the workpiece 1 is not particularly limited. The shape of the workpiece 1 is a disk shape (round plate shape) here. However, the workpiece 1 may have other shapes, such as a block shape (e.g., cubic shape or rectangular parallelepiped shape).

[0014] The adapter 5 holds the disk-shaped workpiece 1. Here, the adapter 5 is a flat adapter having a substantially circular insertion hole 5a corresponding to the workpiece 1 formed in the central portion. The workpiece 1 is held by the adapter 5 by being inserted into the insertion hole 5a. The workpiece 1 is accommodated in the cutting machine 10 and processed while being held by the adapter 5.

[0015] As shown in FIG. 1, the cutting machine 10 has a housing 20 configured in a box shape. An opening for communicating the internal space of the housing 20 with the outside is open on the front side of the housing 20. A processing chamber door 25 and a storage chamber door 26 are provided at the opening so as to be openable and closable, respectively. A processing chamber 21 and a storage chamber 22 are provided behind the processing chamber door 25 and behind the storage chamber door 26, respectively. The processing chamber 21 is an area for cutting the workpiece 1. The storage chamber 22 is an area for storing a plurality of adapters 5 to which the workpiece 1 is respectively attached. The processing chamber 21 and the storage chamber 22 are partitioned by an internal wall. The cutting machine 10 includes a conveying device (not shown) that conveys the adapter 5 housed in the storage chamber 22 to the processing chamber 21 and returns the adapter 5 after the processing of the workpiece 1 is completed to the storage chamber 22.

[0016] FIG. 3 is a perspective view showing the inside of the processing chamber 21. FIG. 4 is a longitudinal sectional view passing through the processing chamber 21 of the cutting machine 10. FIG. 3 shows a state in which some members such as the processing chamber door 25 are removed. As shown in FIGS. 3 and 4, the processing chamber 21 includes a cutting device 30 for cutting the workpiece 1, a holding device 41 for holding the workpiece 1 via the adapter 5, a rotating device 42 for the adapter 5, a tool magazine 45 for storing various cutting tools 6, an X-axis moving device 50X, a Y-axis moving device 50Y (not shown in FIGS. 3 and 4, see FIG. 5), and a Z-axis moving device 50Z for relatively moving the adapter 5 and the cutting device 30.

[0017] As shown in Figure 4, the machining chamber 21 has an inclined wall 21F, a bottom wall 21D, a top wall 21U, a rear wall 21Rr, a left wall 21L, and a right wall 21R (see Figure 3). The front of the machining chamber 21 is open, forming an opening 21a. The opening 21a is provided with a machining chamber door 25 that can open and close the opening 21a. The inclined wall 21F and the bottom wall 21D are located below the cutting device 30. The inclined wall 21F is connected to the lower edge of the opening 21a and slopes downward toward the rear side of the cutting machine 10. The bottom wall 21D is connected to the rear end of the inclined wall 21F. The bottom wall 21D is provided approximately horizontally. Cutting chips from the workpiece 1 that accumulate on the inclined wall 21F are guided to the bottom wall 21D along the downward slope of the inclined wall 21F. The rear wall 21Rr is connected to the bottom wall 21D and extends so as to intersect with the bottom wall 21D. Here, the rear wall 21Rr is connected to the rear end of the bottom wall 21D and extends in a direction perpendicular to the inclined wall 21F. The left wall 21L is connected to the left end of the inclined wall 21F and the bottom wall 21D and the left end of the rear wall 21Rr and extends diagonally upward. The right wall 21R is connected to the right end of the inclined wall 21F and the bottom wall 21D and the right end of the rear wall 21Rr and extends diagonally upward. The opening 21a opens approximately parallel to the rear wall 21Rr. Hereafter, the diagonal front-to-back direction approximately perpendicular to the rear wall 21Rr will also be called the Y-axis direction. Also, the diagonal up-and-down direction approximately perpendicular to the inclined wall 21F will also be called the Z-axis direction. The left-to-right direction will also be called the X-axis direction as appropriate.

[0018] The cutting device 30 cuts the workpiece 1 held by the holding device 41. As shown in Figure 4, the cutting device 30 includes a spindle 31 extending in the Z-axis direction and a tool gripping part 32 provided at the tip of the spindle 31. The tool gripping part 32 is configured to grip the cutting tool 6. The tool gripping part 32 includes, for example, a collet chuck that opens and closes with air drive. However, the configuration of the tool gripping part 32 is not limited. The spindle 31 is configured to rotate around its axis. A spindle motor 33 that rotates the spindle 31 is connected to the spindle 31. When the spindle 31 is rotated with the cutting tool 6 gripped by the tool gripping part 32, the cutting tool 6 rotates around the axis of the spindle 31.

[0019] The holding device 41 holds the workpiece 1 by holding the adapter 5 that holds the workpiece 1. Here, the holding device 41 has a U-shaped arm that opens to the left and holds the adapter 5 inserted between the arms. However, the configuration of the holding device 41 is not particularly limited. The rotating device 42 is configured to rotate the holding device 41 around a first rotation axis 42a that extends in the X-axis direction and around a second rotation axis 42b that is perpendicular to the first rotation axis 42a. The rotating device 42 includes a first motor 43 (see Figure 5) that rotates the holding device 41 around the first rotation axis 42a and a second motor 44 (see Figure 5) that rotates the holding device 41 around the second rotation axis 42b. By rotating the holding device 41 with the rotating device 42, the orientation of the workpiece 1 relative to the cutting device 30 can be changed.

[0020] The Z-axis moving device 50Z is configured to move the cutting device 30 in the Z-axis direction. The X-axis moving device 50X is configured to move the cutting device 30 in the X-axis direction via the Z-axis moving device 50Z. The Y-axis moving device 50Y (see Figure 5), which is not shown in Figures 3 and 4, is configured to move the rotating device 42, the holding device 41, and the tool magazine 45 in the Y-axis direction. The Y-axis moving device 50Y moves the workpiece 1 in the Y-axis direction by moving the rotating device 42 and the holding device 41 in the Y-axis direction. With these configurations, it is possible to move the workpiece 1 in the X-axis, Y-axis, and Z-axis directions relative to the cutting device 30. Here, the X-axis moving device 50X, the Y-axis moving device 50Y, and the Z-axis moving device 50Z each include a motor and a ball screw mechanism, which are not shown. However, the mechanism for moving the workpiece 1 in the X-axis, Y-axis, and Z-axis directions relative to the cutting device 30 is not limited to the above.

[0021] The cutting machine 10 is equipped with a connection part 60 to which an external dust collector 80 can be connected. The dust collector 80 collects cutting chips from the workpiece 1 by generating negative pressure and sucking in air. As shown in Figure 4, the connection part 60 opens on the rear of the housing 20. A dust collection port 61 opens in the rear wall 21Rr of the machining chamber 21. The dust collection port 61 is an opening through which cutting chips from the workpiece 1 inside the machining chamber 21 are sucked in. As shown in Figure 3, the dust collection port 61 is connected to the connection part 60 by a connecting pipe 62. The dust collection port 61 is connected to the dust collector 80 via the connecting pipe 62, the connection part 60, and a dust collection pipe 81 that connects the connection part 60 to the dust collector 80. When the dust collector 80 is driven, air is sucked in from the dust collection port 61. As a result, cutting chips from the workpiece 1 inside the machining chamber 21 are sucked into the dust collector 80.

[0022] The dust collection port 61 is located at the connection point between the bottom wall 21D and the rear wall 21Rr of the machining chamber 21. The dust collection port 61 is located below the cutting device 30. As shown in Figure 3, the dust collection port 61 opens into the rear wall 21Rr so as to reach the lower end of the rear wall 21Rr. The dust collection port 61 is connected to the rear end of the bottom wall 21D. The dust collection port 61 consists of multiple slits 61a to 61c, each extending in the X-axis direction and aligned in the Z-axis direction. The uppermost slit (the slit furthest from the bottom wall 21D) 61a has a larger width in the Z-axis direction than the two lower slits 61b and 61c (on the bottom wall 21D side). As will be described in more detail later, the opening area of ​​the dust collection port 61 can be changed by attaching a throttling cover 91 (see Figure 7) to the dust collection port 61. Here, the opening area of ​​the dust collection port 61 is reduced by attaching a throttling cover 91 to the dust collection port 61. Figures 3 and 4 show the dust collection port 61 without the throttling cover 91 attached.

[0023] The cutting machine 10 is equipped with an air intake port 65 that draws in outside air into the processing chamber 21 as the air inside the processing chamber 21 is discharged by the dust collector 80. As shown in Figure 4, the air intake port 65 is located on the rear side of the cutting machine 10. The air intake port 65 is located above the cutting device 30. A duct 66 is connected to the air intake port 65. The duct 66 extends in the front-rear direction. The rear end of the duct 66 is connected to the air intake port 65. The front end of the duct 66 is bent downward along the opening 21a of the processing chamber 21. A nozzle 67 is formed at the tip (lower end) of the downwardly bent duct 66 from which the air drawn in from the air intake port 65 is ejected. With this arrangement of the air intake port 65 and dust collection port 61, the air drawn in from the air intake port 65 and discharged from the dust collection port 61 flows through the processing chamber 21 from top to bottom and from front to back (see arrow W in Figure 4).

[0024] Figure 5 is a block diagram of the cutting machine 10. As shown in Figure 5, the control device 70 is connected to the tool gripping unit 32, the spindle motor 33, the first motor 43, the second motor 44, the X-axis moving device 50X, the Y-axis moving device 50Y, and the Z-axis moving device 50Z, and controls their operation. The dust collector 80 may or may not be controlled by the control device 70. The dust collector 80 may be operated by the user. Figure 5 illustrates the case where the dust collector 80 is connected to the control device 70. The control device 70 is, for example, a microcomputer. The hardware configuration of the control device 70 is not particularly limited, but for example, it includes an interface (I / F) for receiving cutting data etc. from an external device such as a host computer, a central processing unit (CPU) that executes instructions for the control program, a ROM (read-only memory) that stores the program executed by the CPU, a RAM (random access memory) used as a working area for expanding the program, and a storage device such as memory that stores the above program and various data. The control device 70 does not necessarily have to be located inside the cutting machine 10; for example, it may be installed outside the cutting machine 10 and connected to the cutting machine 10 via wired or wireless communication, such as a computer.

[0025] As shown in Figure 5, the control device 70 includes a storage unit 71, an input unit 72, and an instruction unit 73 as processing units for collecting cutting chips from the workpiece 1. The storage unit 71 stores a predetermined table that associates cutting conditions, including the material of the workpiece 1, with the opening area of ​​the dust collection port 61. In this embodiment, "opening area of ​​the dust collection port 61" means either a state where the aperture cover 91 is not attached to the dust collection port 61 (large opening area) or a state where the aperture cover 91 is attached to the dust collection port 61 (small opening area). The predetermined table is a cover selection table that determines whether or not the aperture cover 91 should be attached in accordance with the cutting conditions, including the material of the workpiece 1. The cutting conditions, including the material of the workpiece 1, are input to the input unit 72. In addition to the material of the workpiece 1, the cutting conditions input to the input unit 72 may also include the cumulative usage time of the cutting tool 6, the depth of cut of the cutting tool 6, etc. However, the cutting conditions entered into the input unit 72 are not particularly limited. The cutting conditions may be entered manually by the user or obtained from cutting data. The instruction unit 73 instructs whether or not to attach the aperture cover 91 based on the cutting conditions entered into the input unit 72 and the cover selection table stored in the storage unit 71. Note that the storage unit 71, the input unit 72, and the instruction unit 73 may be configured by hardware or software separate from the control device 70.

[0026] Figure 6 shows an example of the cover selection table T1. However, the cover selection table T1 shown in Figure 6 is only an example, and the cover selection table T1 is not limited to this. As shown in Figure 6, according to the cover selection table T1 in this example, if the material of the workpiece 1 is a soft material that tends to produce large cutting chips, such as wax, dental resin, ABS, or PMMA, it is instructed to attach the throttling cover 91 to reduce the opening area of ​​the dust collection port 61. On the other hand, according to the cover selection table T1, if the material of the workpiece 1 is a hard material that tends to produce small cutting chips, such as zirconia or gypsum, it is instructed not to attach the throttling cover 91 and to keep the opening area of ​​the dust collection port 61 large. The reason for this will be explained later. For example, if the cutting data indicates that the workpiece 1 will be formed into a predetermined molded product such as a denture base, or if the user inputs that the workpiece 1 will be formed into the above predetermined molded product, it may be determined that the material of the workpiece 1 is a soft material, and it may be instructed to attach the throttling cover 91. Conversely, for example, if the cutting data indicates that the workpiece 1 is to be formed into a predetermined molded product such as an artificial tooth, or if the user has entered that the workpiece 1 is to be formed into the above predetermined molded product, then the material of the workpiece 1 may be determined to be a hard material, and the system may be instructed not to attach the throttling cover 91.

[0027] In the example shown in Figure 6, the cover selection table T1 instructs whether or not to install the aperture cover 91 in accordance with the cutting conditions, but it may also instruct which of the multiple types of aperture covers 91 to install (or not to install any aperture covers 91). In this case, the multiple types of aperture covers 91 may be configured such that the opening area of ​​the dust collection port 61 differs from that of the other when installed on the dust collection port 61.

[0028] [Configuration of aperture cover] Figure 7 is a perspective view of the aperture cover 91. Figure 8 is a longitudinal cross-sectional view showing the aperture cover 91 mounted on the dust collection port 61. In this embodiment, the aperture cover 91 constitutes an aperture mechanism 90 that can change the opening area of ​​the dust collection port 61. However, as shown in the second embodiment described later, for example, the aperture mechanism 90 is not limited to one that includes the aperture cover 91. The aperture mechanism 90 may also include components other than the aperture cover 91, such as a member for fixing the aperture cover 91. In the following description of Figures 7 and 8, the orientation when the aperture cover 91 is mounted in the processing chamber 21 will be used as appropriate. As shown in Figures 7 and 8, the aperture cover 91 has a pair of left and right substantially triangular side plates 92 and a front plate 93 that extends in the left-right direction so as to connect the hypotenuses of the pair of side plates 92. The space behind the front plate 93 and between the pair of side plates 92 forms the internal space of the aperture cover 91 when it is mounted in the processing chamber 21. In this case, the aperture cover 91 is made from a single material. However, the aperture cover 91 may be formed by joining multiple parts, for example, a pair of side plates 92 and a front plate 93.

[0029] As shown in Figure 7, a first dust collection hole 94 is opened in the lower edge 92a of each of the pair of side plates 92 (in Figure 7, only the right first dust collection hole 94 is shown; see Figure 8 for the left first dust collection hole 94). The first dust collection hole 94 is a notch formed to cut through the lower edge 92a and rear edge 92b of the side plate 92. A second dust collection hole 95 is opened in the lower edge 93a of the front plate 93. The second dust collection hole 95 is a notch formed to cut through the lower edge 93a of the front plate 93. The second dust collection hole 95 has a lower part 95a that is wider in the X-axis direction and an upper part 95b that is formed above the lower part 95a and is narrower in the X-axis direction than the lower part 95a. The lower part 95a is formed over the entire width in the X-axis direction, leaving the thickness of the pair of side plates 92. As shown in Figure 8, the pair of side plates 92 protrude rearward from the rear end 93b (which is also the upper end) of the front plate 93, and the gap behind the rear end of the front plate 93 forms the third dust collection hole 96 when the throttling cover 91 is installed in the processing chamber 21.

[0030] Thus, in this embodiment, the aperture cover 91 has a total of four dust collection holes: a pair of first dust collection holes 94, a second dust collection hole 95, and a third dust collection hole 96. The total opening area of ​​the multiple dust collection holes 94-96 is smaller than the opening area of ​​the dust collection port 61. However, the aperture cover 91 may have, for example, one dust collection hole with an opening area smaller than that of the dust collection port 61, instead of the multiple dust collection holes 94-96.

[0031] [Attaching the aperture cover] The aperture cover 91 is configured to be detachably attached to the processing chamber 21. The aperture cover 91 is installed in the processing chamber 21 so as to cover the dust collection port 61. Here, the aperture cover 91 is placed on the connection between the bottom wall 21D and the rear wall 21Rr of the processing chamber 21 so as to cover the dust collection port 61. Figure 9 is a perspective view showing the inside of the processing chamber 21, and shows the aperture cover 91 installed on the dust collection port 61. As shown in Figures 8 and 9, when installed, the aperture cover 91 abuts against the bottom wall 21D and the rear wall 21Rr of the processing chamber 21, and together with the bottom wall 21D and the rear wall 21Rr, it covers the dust collection port 61. Specifically, the rear edge 92b of the side plate 92 of the aperture cover 91 abuts against the rear wall 21Rr of the processing chamber 21. The lower edge 92a of the side plate 92 and the lower edge 93a of the front plate 93 abut against the bottom wall 21D of the processing chamber 21.

[0032] As shown in Figure 8, of the multiple dust collection holes 94 to 96, a pair of first dust collection holes 94 and second dust collection holes 95 open so as to intersect with the edges of the throttling cover 91 that are in contact with the bottom wall 21D of the machining chamber 21. Here, the pair of first dust collection holes 94 open so as to intersect with the lower edge 92a of the side plate 92 that is in contact with the bottom wall 21D of the machining chamber 21. The second dust collection hole 95 opens so as to intersect with the lower edge 93a of the front plate 93 that is in contact with the bottom wall 21D of the machining chamber 21. It is preferable that at least one of the one or more dust collection holes open so as to intersect with the edges of the throttling cover 91 that are in contact with the bottom wall 21D of the machining chamber 21. However, the throttling cover 91 is not required to have dust collection holes that intersect with the edges that are in contact with the bottom wall 21D of the machining chamber 21. The third dust collection hole 96 is located below the cutting device 30 and opens upward.

[0033] By attaching the diaphragm cover 91 to the dust collection port 61, the opening area of ​​the dust collection port 61 decreases compared to when the diaphragm cover 91 is not attached. As mentioned above, the total opening area of ​​the multiple dust collection holes 94-96 is smaller than the opening area of ​​the dust collection port 61. When the diaphragm cover 91 is attached, "the opening area of ​​the dust collection port 61" refers to the total opening area of ​​the dust collection holes 94-96 of the diaphragm cover 91. When the dust collector 80 is driven with the diaphragm cover 91 attached, air from inside the processing chamber 21 is drawn in through the dust collection holes 94-96 of the diaphragm cover 91, which act as a new dust collection port. As the opening area of ​​the dust collection port 61 decreases, the flow velocity of the air flowing into the dust collection holes 94-96 increases. On the other hand, as the opening area of ​​the dust collection port 61 decreases, the flow rate (amount of air per unit time) of the air flowing into the dust collection holes 94-96 decreases. When the aperture cover 91 is not attached to the dust collection port 61, the airflow rate into the dust collection holes 94-96 increases and the flow velocity decreases compared to when the aperture cover 91 is attached.

[0034] Based on the above, when collecting cutting chips that are easier to collect with a larger flow rate at the dust collection port 61, it is preferable not to attach the throttling cover 91 to the dust collection port 61. Conversely, when collecting cutting chips that are easier to collect with a faster flow velocity at the dust collection port 61, it is preferable to attach the throttling cover 91 to the dust collection port 61. According to the inventors' findings, when the material of the workpiece 1 is a material such as zirconia or gypsum, small and lightweight cutting chips tend to be generated. According to further findings of the inventors, when collecting small and lightweight cutting chips, a larger flow rate at the dust collection port 61 results in higher collection efficiency, and the flow velocity at the dust collection port 61 does not contribute much to the collection efficiency. On the other hand, when the material of the workpiece 1 is a material such as wax, dental resin, ABS, or PMMA, large and heavy cutting chips tend to be generated. According to further findings of the inventors, when collecting large and heavy cutting chips, the collection efficiency will not improve unless the flow velocity at the dust collection port 61 is increased. According to the inventors of this application, this is because large and heavy cutting chips are difficult to move unless the airflow velocity is increased to increase the force that moves the cutting chips. The cover selection table T1 is set based on this finding.

[0035] [Cutting procedure] The following describes an example of a cutting procedure using the cutting machine 10 according to this embodiment. In cutting a workpiece 1 using the cutting machine 10 according to this embodiment, first, the user inputs the cutting conditions for the workpiece 1, in this case the material of the workpiece 1, by operating the input screen displayed on a computer display device or the like by the input unit 72 of the control device 70. Preferably, the material of the workpiece 1 is input by selecting it from a predetermined list of materials. As mentioned above, this input operation may be performed automatically based on information obtained from cutting data, etc.

[0036] When the cutting conditions for the workpiece 1 are entered, the cutting machine 10 instructs whether or not to attach the throttling cover 91 to the dust collection port 61 based on the entered cutting conditions and the stored cover selection table T1. Based on this instruction, the user either attaches the throttling cover 91 to the dust collection port 61 or does not attach it. Then, the adapter 5 with the workpiece 1 attached is set in the storage chamber 22 (this step is omitted if it is already set), and the cutting process is started. At this time, the dust collector 80 is driven. This causes air to flow into the dust collection port 61 at an appropriate flow rate and velocity corresponding to the size of the cutting chips. As a result, the cutting chips are efficiently collected in the dust collector 80.

[0037] [Effects of the First Embodiment] The effects and advantages of this embodiment will be described below. The cutting machine 10 according to this embodiment includes a cutting device 30 for cutting a workpiece 1, a processing chamber 21 in which the cutting device 30 is housed, a dust collection port 61 that opens into the processing chamber 21 and is connected to a dust collector 80, and a throttling mechanism 90 configured to change the opening area of ​​the dust collection port 61. With this configuration, by adjusting the opening area of ​​the dust collection port 61 with the throttling mechanism 90, suitable dust collection conditions corresponding to the size of the cutting chips can be obtained. For example, when the cutting chips are fine (in the above example, when the workpiece 1 is made of a material such as zirconia or gypsum), the opening area of ​​the dust collection port 61 can be increased by the throttling mechanism 90 (in this embodiment, the throttling cover 91 is not attached), thereby increasing the airflow at the dust collection port 61. This makes it possible to efficiently collect fine cutting chips. Furthermore, for example, when the cutting chips are large (in the example above, when the workpiece 1 is made of materials such as wax, dental resin, ABS, or PMMA), the opening area of ​​the dust collection port 61 can be reduced by the throttling mechanism 90 (in this embodiment, a throttling cover 91 is attached), thereby increasing the airflow velocity at the dust collection port 61. This allows for efficient collection of large cutting chips. Therefore, the cutting machine 10 can achieve high dust collection efficiency regardless of the size of the cutting chips.

[0038] In this embodiment, the diaphragm mechanism 90 is configured to be detachably attached to the processing chamber 21 and includes a diaphragm cover 91 that is mounted on the processing chamber 21 so as to cover the dust collection port 61. The diaphragm cover 91 has one or more dust collection holes, in this case a plurality of dust collection holes 94 to 96, with a total opening area smaller than that of the dust collection port 61. With this configuration, the opening area of ​​the dust collection port 61 can be changed by the simple operation of attaching or detaching the diaphragm cover 91. Furthermore, with this configuration, the structure of the diaphragm mechanism 90 can be simplified, and the cost related to the diaphragm mechanism 90 can be reduced.

[0039] In this embodiment, the dust collection port 61 is provided at the connection between the bottom wall 21D and the rear wall 21Rr of the processing chamber 21, and the throttling cover 91, when installed, abuts against the bottom wall 21D and the rear wall 21Rr of the processing chamber 21. When installed in the processing chamber 21, the throttling cover 91 is configured to cover the dust collection port 61 together with the bottom wall 21D and the rear wall 21Rr of the processing chamber 21. The bottom wall 21D of the processing chamber 21 is located below the cutting device 30. Therefore, cutting chips from the workpiece 1 accumulate on the bottom wall 21D of the processing chamber 21. Furthermore, the inclination of the inclined wall 21F and the airflow W (see Figure 4) guide the cutting chips from the workpiece 1 that have accumulated on the inclined wall 21F to the bottom wall 21D of the processing chamber 21. In this embodiment, since the dust collection port 61 is provided at the connection between the bottom wall 21D and the rear wall 21Rr of the machining chamber 21, cutting chips from the workpiece 1 that have accumulated on the bottom wall 21D of the machining chamber 21 can be efficiently collected. Furthermore, since the bottom wall 21D and the rear wall 21Rr of the machining chamber 21 are used to cover the dust collection port 61, the configuration of the aperture cover 91 can be simplified. In this example, the back and bottom of the aperture cover 91 are omitted.

[0040] Furthermore, in this embodiment, the first dust collection hole 94 and the second dust collection hole 95 among the dust collection holes 94-96 are opened so as to intersect with the edges of the diaphragm cover 91 that are in contact with the bottom wall 21D of the machining chamber 21 (here, the lower edge 92a of the side plate 92 and the lower edge 93a of the front plate 93, respectively). With this configuration, when the diaphragm cover 91 is attached, cutting chips from the workpiece 1 that accumulate on the bottom wall 21D of the machining chamber 21 can be collected more efficiently. In this embodiment, the second dust collection hole 95 faces forward, that is, toward the inclined wall 21F in the front-to-back direction, and can suck up a large amount of cutting chips. The pair of first dust collection holes 94 are located behind the second dust collection hole 95, that is, further away from the inclined wall 21F than the second dust collection hole 95 in the front-to-back direction, and open in the left-to-right direction. Therefore, much of the cutting chips that were collected on the bottom wall 21D of the processing chamber 21 but not sucked into the second dust collection hole 95 can be sucked up. The third dust collection hole 96 does not intersect with the side of the throttling cover 91 that is in contact with the bottom wall 21D, but it can suck up cutting chips that fall from above towards the dust collection port 61.

[0041] When the throttling cover 91 is not installed, the cutting debris that accumulates on the bottom wall 21D of the machining chamber 21 is sucked in through the three slits 61a, 61b, and 61c of the dust collection port 61. Here, the opening area of ​​the dust collection port 61 (the total opening area of ​​slits 61a, 61b, and 61c) is larger than the cross-sectional area of ​​the connection part 60. This prevents loss of airflow and a decrease in the air velocity at the dust collection port 61.

[0042] The dust collection port 61 may be provided at the connection point between the bottom wall 21D of the processing chamber 21 and the other wall portion of the processing chamber 21, excluding the bottom wall 21D and the rear wall 21Rr. The dust collection port 61 may also be provided at the connection point between the bottom wall 21D of the processing chamber 21 and, for example, the left wall 21L. In this embodiment, the inclined wall 21F slopes downward toward the rear. Therefore, it is preferable that the dust collection port 61 be provided at the connection point between the bottom wall 21D and the rear wall 21Rr of the processing chamber 21. However, the cutting machine 10 does not need to have an inclined wall 21F in the processing chamber 21, and even if an inclined wall is provided, the direction of inclination of the inclined wall is not limited. Therefore, for example, in other configurations where the direction of inclination of the inclined wall is different, the preferred position of the dust collection port 61 may be at the connection point between the bottom wall 21D of the processing chamber 21 and the other wall portion of the processing chamber 21, excluding the bottom wall 21D and the rear wall 21Rr. Furthermore, for example, if the bottom wall 21D of the processing chamber 21 is formed in a mortar shape, a suitable position for the dust collection port 61 may be the lowest part of the bottom wall 21D.

[0043] In this embodiment, the control device 70 of the cutting machine 10 includes a storage unit 71 that stores a predetermined cover selection table T1 which associates cutting conditions, including the material of the workpiece 1, with the opening area of ​​the dust collection port 61; an input unit 72 into which cutting conditions are input; and an instruction unit 73 that instructs whether or not to attach the narrowing cover 91 based on the cutting conditions input to the input unit 72 and the cover selection table T1 stored in the storage unit 71. With this configuration, the cutting machine 10 can determine whether or not to attach the narrowing cover 91 without the user having to make a decision. Therefore, the cutting machine 10 can appropriately determine whether or not to attach the narrowing cover 91. Furthermore, there is no need to spend time and effort making a decision.

[0044] The cutting machine 10 does not necessarily have to be configured to instruct whether or not to attach the aperture cover 91. In that case, the user may decide whether or not to attach the aperture cover 91.

[0045] The shape of the throttling cover 91 is not limited to those described above. The throttling cover 91 may be, for example, a flat plate-shaped member with one or more dust collection holes formed therein. In the above embodiment, the throttling cover 91 was attached to the dust collection port 61 only when it was desired to increase the airflow velocity at the dust collection port 61, but the cutting machine 10 may be configured to always attach one of several types of throttling covers 91 to the dust collection port 61.

[0046] [Second Embodiment] In the cutting machine according to the second embodiment, the throttling mechanism is controlled, and the opening area of ​​the dust collection port is automatically changed according to the cutting conditions of the workpiece. In the following description of the second embodiment, and in the descriptions of other embodiments, the same reference numerals as in the first embodiment shall be used for components that perform functions common to the first embodiment. In addition, descriptions that overlap with the description of the first embodiment will be omitted or simplified.

[0047] Figure 10 is a schematic partially broken perspective view showing the machining chamber 21 of the cutting machine 10 according to the second embodiment. As shown in Figure 10, in this embodiment, the bottom of the machining chamber 21 is formed by a movable bottom wall 101 and a fixed bottom wall 102. A gap is provided between the movable bottom wall 101 and the fixed bottom wall 102. In this embodiment, this gap constitutes the dust collection port 61. The movable bottom wall 101 is configured to be rotatable. By rotating the movable bottom wall 101, the opening area of ​​the dust collection port 61 (the gap between the movable bottom wall 101 and the fixed bottom wall 102) is changed. In this embodiment, the throttling mechanism 90 thus includes a movable bottom wall 101 that constitutes a part of the edge of the dust collection port 61 and moves to enlarge or reduce the dust collection port 61. Here, the edge of the dust collection port 61 that the movable bottom wall 101 constitutes is the front edge of the dust collection port 61.

[0048] As shown in Figure 10, the movable bottom wall 101 is positioned on the front side of the processing chamber 21, and the fixed bottom wall 102 is positioned behind the movable bottom wall 101. The dust collection port 61 extends in the left-right direction between the movable bottom wall 101 and the fixed bottom wall 102. The fixed bottom wall 102 slopes downward toward the dust collection port 61 (in this case toward the front). The movable bottom wall 101 also slopes downward toward the dust collection port 61 (in this case toward the rear), but its angle of inclination changes with the rotation of the movable bottom wall 101.

[0049] The aperture mechanism 90 includes a pivot shaft 103 that supports the movable bottom wall 101 so that it can rotate in the vertical direction, and a drive unit 104 (see Figure 11) that rotates the movable bottom wall 101 around the pivot shaft 103. As shown in Figure 10, the pivot shaft 103 extends in the left-right direction. The pivot shaft 103 supports the front end of the movable bottom wall 101. The drive unit 104 is, for example, a stepping motor or servo motor whose rotational position can be controlled. However, the drive unit 104 is not limited to an electric motor, and may be, for example, an air-driven actuator. The drive unit 104 may also be an actuator whose rotational position cannot be controlled, in which case the aperture mechanism 90 may be equipped with a sensor that detects the position of the movable bottom wall 101.

[0050] Figure 11 is a block diagram of the cutting machine 10 according to this embodiment. In this embodiment, the control device 70 controls the drive unit 104. As shown in Figure 11, the control device 70 according to this embodiment includes a storage unit 71, an input unit 72, a determination unit 74, and a drive control unit 75. The storage unit 71 stores a predetermined table T2 (hereinafter referred to as the opening degree selection table T2, see Figure 12) which associates cutting conditions, including the material of the workpiece 1, with the opening area of ​​the dust collection port 61. Cutting conditions are input to the input unit 72. The input unit 72 may be the same as in the first embodiment. The determination unit 74 determines the opening area of ​​the dust collection port 61 based on the cutting conditions input to the input unit 72 and the opening degree selection table T2 stored in the storage unit 71. The drive control unit 75 controls the drive unit 104 to set the opening area of ​​the dust collection port 61 to the opening area determined by the determination unit 74. In this embodiment, "determining the opening area of ​​the dust collection port 61" and "setting the opening area of ​​the dust collection port 61 to a predetermined opening area" mean determining the rotational position of the movable bottom wall 101 and controlling the rotational position of the movable bottom wall 101 to the determined rotational position.

[0051] Figure 12 shows an example of an aperture selection table T2. As shown in Figure 12, according to the aperture selection table T2 exemplified here, the cutting conditions include the material of the workpiece 1, the cumulative usage time of the cutting tool 6, and the depth of cut during cutting. Also, as shown in Figure 12, in the aperture selection table T2, the aperture of the dust collection port 61 is divided into three stages: "large," "medium," and "small."

[0052] Figure 13 is a schematic longitudinal cross-sectional view of the machining chamber 21 showing the rotational positions of the movable bottom wall 101. In Figure 13, the movable bottom wall 101 shown by the solid line represents the movable bottom wall 101 when the opening degree is "small". This position of the movable bottom wall 101 will be referred to as the first rotational position R1 below. In Figure 13, one of the movable bottom walls 101 shown by the dashed-dot line represents the movable bottom wall 101 when the opening degree is "medium". This position of the movable bottom wall 101 will be referred to as the second rotational position R2 below. In Figure 13, the other movable bottom wall 101 shown by the dashed-dot line represents the movable bottom wall 101 when the opening degree is "large". This position of the movable bottom wall 101 will be referred to as the third rotational position R3 below.

[0053] As shown in Figure 13, when the movable bottom wall 101 is in the first rotation position R1 (when the opening degree is "small"), the opening area of ​​the dust collection port 61 is smaller than in other rotation positions. Therefore, when the opening degree is "small", the airflow velocity at the dust collection port 61 is faster than in other opening degrees. Also, when the opening degree is "small", the airflow rate at the dust collection port 61 is smaller than in other opening degrees.

[0054] When the movable bottom wall 101 is in the third rotation position R3 (when the opening degree is "large"), the opening area of ​​the dust collection port 61 is larger than in other rotation positions. Therefore, when the opening degree is "large", the airflow rate at the dust collection port 61 is greater than in other opening degrees. Also, when the opening degree is "large", the airflow velocity at the dust collection port 61 is slower than in other opening degrees. When the movable bottom wall 101 is in the second rotation position R2 (when the opening degree is "medium"), the opening area of ​​the dust collection port 61 is larger than in the first rotation position R1 and smaller than in the third rotation position R3. Therefore, when the opening degree is "medium", the airflow rate at the dust collection port 61 is greater than in the "small" opening and smaller than in the "large" opening. Also, when the opening degree is "medium", the airflow velocity at the dust collection port 61 is faster than in the "large" opening and slower than in the "small" opening.

[0055] As shown in Figure 12, according to the opening degree selection table T2 illustrated here, when the material of the workpiece 1 is wax, the opening degree of the dust collection port 61 is selected as "small" regardless of other cutting conditions. Since wax tends to produce large chips regardless of other cutting conditions, when the material of the workpiece 1 is wax, the opening degree of the dust collection port 61 is set to "small" to increase the airflow velocity at the dust collection port 61.

[0056] As shown in Figure 12, according to the aperture selection table T2, when the material of the workpiece 1 is zirconia or gypsum, the aperture of the dust collection port 61 is selected as "large" regardless of other cutting conditions. Since zirconia and gypsum tend to produce smaller cutting chips regardless of other cutting conditions, when the material of the workpiece 1 is zirconia or gypsum, the aperture of the dust collection port 61 is set to "large" to increase the airflow rate at the dust collection port 61.

[0057] As shown in Figure 12, according to the aperture selection table T2, when the material of the workpiece 1 is PMMA, the aperture of the dust collection port 61 is selected as "medium" regardless of other cutting conditions. Also, according to the aperture selection table T2, when the material of the workpiece 1 is dental resin or ABS, the aperture of the dust collection port 61 is selected as "small" or "medium" depending on other cutting conditions. With dental resin and ABS, the cutting tool 6 tends to become dull when used for a long time, or when the depth of cut is increased, resulting in larger cutting chips. Therefore, when the material of the workpiece 1 is dental resin or ABS, when the usage time of the cutting tool 6 is longer than a predetermined time, or when the depth of cut is greater than a predetermined amount, the aperture of the dust collection port 61 is set to "small" to increase the airflow velocity at the dust collection port 61.

[0058] [Effects of the second embodiment] As described above, according to this embodiment, the diaphragm mechanism 90 includes a movable bottom wall 101 as a movable member that constitutes a part of the edge of the dust collection port 61 and moves to enlarge or reduce the dust collection port 61. With this configuration, the opening area of ​​the dust collection port 61 can be easily changed by moving the movable bottom wall 101 as a movable member. Note that the method of moving the movable member is not limited to a rotational method. For example, the method of moving the movable member may be a sliding method (for example, a shutter method in which the degree of opening can be controlled).

[0059] In this embodiment, the throttling mechanism 90 includes a drive unit 104 for moving the movable bottom wall 101. With this configuration, the movable bottom wall 101 can be moved by the driving force of the drive unit 104 without the user having to move the movable bottom wall 101 by hand. Furthermore, in this embodiment, the control device 70 includes a determination unit 74 that determines the opening area of ​​the dust collection port 61 based on the cutting conditions input to the input unit 72 and the opening degree selection table T2, and a drive control unit 75 that controls the drive unit 104 to set the opening area of ​​the dust collection port 61 to the determined opening area. As a result, the opening area of ​​the dust collection port 61 can be automatically set to a suitable opening area in accordance with the cutting conditions of the workpiece 1.

[0060] However, movable members such as the movable bottom wall 101 may be moved by the user. Even if the throttling mechanism 90 is equipped with a drive unit 104 for moving the movable members, the user may determine the degree of opening of the dust collection port 61. In that case, the cutting machine 10 may be equipped with, for example, an operation screen for setting the degree of opening of the dust collection port 61, and the drive unit 104 may be controlled to achieve the degree of opening set on the operation screen.

[0061] [Other embodiments] Several preferred embodiments of cutting machines have been described above. However, the technology disclosed herein can also be implemented in other forms other than those described above. For example, in the embodiments described above, the cutting machine 10 had a sealed machining chamber 21, but the technology disclosed herein can also be applied to cutting processes that do not use a cutting machine having a sealed machining chamber. For example, one such method includes cutting a workpiece and collecting the cutting chips from the workpiece with a dust collector equipped with a dust collection port for drawing in air, and changing the opening area of ​​the dust collection port according to the size or shape of the cutting chips. For example, elongated cutting chips are difficult to collect unless the air velocity is high, so the opening area of ​​the dust collection port may also be changed depending on the shape of the cutting chips. The method of cutting the workpiece is not limited and may be performed, for example, using a manual tool or in an open space. The method of changing the opening area of ​​the dust collection port is also not particularly limited. The opening area of ​​the dust collection port may be changed, for example, by attaching and detaching an attachment that changes the opening area to a dust collection port provided at the end of a hose-shaped dust collection pipe. In the above method, the opening area of ​​the dust collection port may be changed depending on the material of the workpiece to be cut.

[0062] Unless otherwise specified, the embodiments are not limiting to the present invention. For example, the cutting machine does not have to be a dental cutting machine for producing dental molded products. The workpiece does not have to be held by the cutting machine via an adapter, but may be held directly by the cutting machine. [Explanation of Symbols]

[0063] 1 Workpiece 10 Cutting machine 21 Processing room 21D Bottom wall (bottom surface) 21Rr Rear wall (other wall surface) 30 Cutting equipment 61 Dust collection port 70 Control device 71 Memory section 72 Input section 73 Instruction section 74 Decision Section 75 Drive control unit 80 Dust collector 90 Aperture Mechanism 91. Restriction cover (cover component) 94 1st dust collection hole 95 2nd dust collection hole 101 Movable bottom wall (movable member) 104 Drive unit T1 Cover Selection Table (Table) T2 Aperture Selection Table (Table)

Claims

1. A cutting device for cutting a workpiece, A processing chamber housing the aforementioned cutting device, Opening into the aforementioned processing chamber, a dust collection port connected to a dust collector, A throttling mechanism configured to change the opening area of ​​the dust collection port, Equipped with, The throttling mechanism includes a cover member that is detachably configured to be attached to the processing chamber and mounted on the processing chamber so as to cover the dust collection port. A cutting machine wherein the cover member has one or more dust collection holes with a total opening area smaller than that of the dust collection port.

2. The aforementioned processing chamber is A bottom surface provided below the cutting device, It has other wall surfaces connected to the bottom surface and extending so as to intersect with the bottom surface, The dust collection port is provided at the connection between the bottom surface and the other wall surface. The cover member, when installed, abuts against the bottom surface and the other wall surface, and together with the bottom surface and the other wall surface, covers the dust collection opening. The cutting machine according to claim 1.

3. At least one of the one or more dust collection holes is opened so as to intersect with the edge of the cover member that is in contact with the bottom surface. The cutting machine according to claim 2.

4. A storage device that stores a predetermined table relating cutting conditions, including the material of the workpiece, to the opening area of ​​the dust collection port, An input device into which cutting conditions are entered, The system further includes an indicator device that instructs whether or not to attach the cover member based on the cutting conditions input to the input device and the table stored in the storage device, A cutting machine according to any one of claims 1 to 3.

5. A cutting device for cutting a workpiece, A processing chamber housing the aforementioned cutting device, Opening into the aforementioned processing chamber, a dust collection port connected to a dust collector, A throttling mechanism configured to change the opening area of ​​the dust collection port, Equipped with, The aperture mechanism is, A movable member which forms part of the edge of the dust collection port and moves to enlarge or reduce the dust collection port, The system includes a drive unit for moving the aforementioned movable member. The system further includes a control device for controlling the aforementioned drive unit, The control device is A storage unit that stores a predetermined table relating cutting conditions, including the material of the workpiece, to the opening area of ​​the dust collection port, An input section into which cutting conditions are entered, A determination unit that determines the opening area of ​​the dust collection port based on the cutting conditions input to the input unit and the table stored in the storage unit, A cutting machine comprising: a drive control unit that controls the drive unit to set the opening area of ​​the dust collection port to the opening area determined by the determination unit.

6. Cutting the workpiece, This includes collecting cutting chips from the workpiece using a dust collector equipped with a dust collection port that sucks in air, A cutting method that changes the opening area of ​​the dust collection port according to the size or shape of the cutting chips.

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