Chip crusher and chip cutting method

Abstract

To provide a chip crusher and a chip cutting method capable of solving the problem of a time loss or reduction of work efficiency caused by work for removing jamming chips by preventing an emergency stop or a breading accident caused by chip jamming.SOLUTION: A rotary cutter 11 is constructed by alternately fitting large-diameter and small-diameter blades 29 and 31 in a drive shaft 27 driven to rotate by a motor. A fixed cutter 13 engaged with the rotary cutter 11 is fixed to a casing 25 of a cutting part 15 on which the rotary cutter 11 is rotatably supported. Three types of large-diameter blades 29A, 29B, and 29C different in phase are prepared for the large-diameter cutter 29, and an arrangement pattern is formed by combining these blades. As the phases are different, even when many chips 21, 21,... simultaneously drop as a lump, loads are dispersed because the row of upward blades 29d, 29d,... is thinned. In addition, the general-purpose fixed cutter 13 can be directly used. Further, the arrangement pattern can be optimized in accordance with a condition of the chips 21.SELECTED DRAWING: Figure 3

Description

[Technical Field]

[0001] The present invention relates to a chip crusher that finely cuts chips discharged from machine tools and the like to reduce their volume, and to a chip cutting method. [Background technology]

[0002] Chips discharged from machine tools are made of a variety of materials, including metals such as steel and aluminum, and synthetic resins, and come in a variety of shapes, such as curls and spirals, making them very bulky.If the discharged chips were stored in a container as is, the container would quickly become full, resulting in poor storage efficiency and making subsequent post-processing (disposal, etc.) difficult, so chip crushers are used to reduce the volume. A known example of this type of chip crusher is a chip processing device in which a screw shaft is provided inside a cylindrical casing so that it can be rotated and can swing intermittently in the direction of the rotation axis, as disclosed in Patent Document 1. The rotational movement of the screw shaft and the swinging in the axial direction cause chips to be cut between the screw shaft and the inner surface of the cylindrical casing and then pressure-fed. [Prior art documents] [Patent documents]

[0003] [Patent Document 1] Japanese Patent Application Publication No. 6-297294 [Patent Document 2] Patent Publication No. 2021-112788 Summary of the Invention [Problem to be solved by the invention]

[0004] However, with the chip processing device of Patent Document 1, as described above, the wide variety of chip materials and shapes means that clogging is likely to occur, and emergency stops are not uncommon. When a clogging occurs, measures are taken such as reversing rotation to clear the jammed state and then removing the clogged chips, but if the chip processing device stops, the machine tool must also be stopped, resulting in a significant loss of time and ultimately a decrease in work efficiency. Furthermore, depending on the state of jamming, serious problems such as deformation of the rotating shaft or damage to the screw blades may occur. Although safety mechanisms such as torque limiters have been installed, the need to remove the clogged chips after the machine tool has stopped remains, and the problem of reduced work efficiency due to the machine tool being stopped remains.

[0005] In contrast, the chip crusher in Patent Document 2 was proposed by the present applicant, and focuses on the fact that conventional configurations are based on the idea that they process a wide variety of chips without distinguishing between them, which is likely to cause clogging. This specific configuration is based on the idea of ​​preventing clogging by changing the chip crusher side depending on the chip conditions. This specific configuration has been confirmed to have a certain degree of clogging prevention effect.

[0006] The present invention was made in response to the above-mentioned conventional problems, and aims to provide an improved chip crusher and chip cutting method that can prevent emergency stops and damage accidents due to chip clogging and eliminate the problems of time loss and reduced work efficiency caused by the work of removing clogged chips. [Means for solving the problem]

[0007] Like Patent Document 2, this invention is based on the idea of ​​preventing clogging by changing the chip crusher side depending on the chip conditions, but it is clearly distinguishable from the configuration of Patent Document 2.

[0008] Specifically, the invention of claim 1 is a chip crusher that includes a rotary blade in which large diameter blades and small diameter blades are alternately fitted and detachably attached to a drive shaft that is rotationally driven by a motor, and a fixed blade that has a recess into which the large diameter blade fits and a protrusion to which the small diameter blade is adjacent, and that cuts chips with the rotary blade and the fixed blade, The phases of the rows of small diameter blades are aligned, and the phases of the rows of large diameter blades are aligned. Arbitrarily set phase difference The chip crusher is characterized in that the chips are arranged in an array pattern in the axial direction of the drive shaft.

[0009] The invention of claim 2 is a chip crusher according to claim 1, characterized in that even when the phases of the large diameter blades arranged adjacent to each other in the axial direction are shifted, the cross section of the pull-in area perpendicular to the axial direction at the boundary between them is maintained as a V-shaped concave surface.

[0010] The invention of claim 3 is a chip crusher according to claim 1 or 2, characterized in that it is configured with a combination of three types of large diameter blades with different phases.

[0011] The invention of claim 4 is a chip crusher according to any one of claims 1 to 3, characterized in that the large diameter blades are arranged in a periodically changing phase. The invention of claim 5 is a chip crusher according to any one of claims 1 to 4, characterized in that the number of blade portions of the large diameter blades and the number of blade portions of the small diameter blades are the same. The invention of claim 6 is a chip crusher according to any one of claims 1 to 5, characterized in that the large diameter blade and the small diameter blade each have an annular body and a plurality of blade portions formed at equal intervals in the circumferential direction on the outer peripheral surface of the annular body, and the small diameter blade is substantially contained within the annular body of the large diameter blade.

[0012] Claim 7 The invention of A method for cutting chips using the chip crusher according to any one of claims 1 to 6, This cutting method is characterized by preparing multiple types of large diameter blades with different phases, and using a rotary blade with the phase arrangement pattern of the large diameter blades lined up in the axial direction adjusted depending on the conditions of the cutting chips. [Effects of the Invention]

[0013] According to the present invention, it is possible to prevent emergency stops and damage accidents caused by chip clogging, and to eliminate the problems of time loss and reduced work efficiency caused by the work of removing clogged chips. [Brief explanation of the drawings]

[0014] [Figure 1] 1 is a perspective view of a chip crusher according to an embodiment of the present invention. FIG. [Figure 2] FIG. 2 is a top view of the chip crusher of FIG. 1. [Figure 3] FIG. 2 is a perspective view showing a rotary blade of a chip crusher body in the chip crusher shown in FIG. 1. [Figure 4] FIG. 4 is a plan view of the rotary blade of the chip crusher body shown in FIG. 3. [Figure 5] 5 is a side view of a large-diameter blade and a small-diameter blade of the rotary blade shown in FIG. 3 and FIG. 4. [Figure 6] FIG. 2 is a perspective view showing a fixed blade provided on the chip crusher body shown in FIG. 1. [Figure 7] 7 is a partially omitted plan view showing the meshing state between the rotary blade of the chip crusher body shown in FIGS. 3 and 4 and the fixed blade shown in FIG. 6. FIG. [Figure 8] 1A and 1B are a perspective view and a plan view of a rotary blade of arrangement pattern (1). [Figure 9] 10A and 10B are a perspective view and a plan view of the rotary blades of arrangement pattern (2). [Figure 10] 10A and 10B are a perspective view and a plan view of the rotary blades of arrangement pattern (3). DETAILED DESCRIPTION OF THE INVENTION

[0015] A chip crusher 1 according to an embodiment of the present invention will be described below with reference to the drawings. As shown in FIG. 1, the chip crusher 1 has a movable base 5 equipped with a plurality of casters 3 at the bottom end, a chip crusher body 7 arranged on the upper surface of the base 5, a hopper 9, etc. The chip crusher body 7 has an open-top cutting section 15 that houses the rotary blade 11 and the fixed blade 13 (see Figure 2), a motor 17 as a drive source for rotating the rotary blade 11, and an orthogonal shaft reducer 19 that transmits the rotation of the motor 17 to the rotary blade 11. The hopper 9 is fixed to the upper surface of the cutting section 15, and chips 21 generated by a machine tool (not shown) are transported by a chip conveyor 23, fall, and are introduced into the hopper 9 through an opening 9a and supplied to the cutting section 15. The hopper 9 also serves as a safety cover to prevent scattering of chips 21, and is made of a transparent material such as an acrylic plate so that the processing status of chips 21 can be seen from the outside. The front side of the hopper 9 (the fixed blade 13 side) is openable and closable.

[0016] As shown in Fig. 2, the fixed blade 13 is fixed to the inside of the front side of the casing 25 of the cutting section 15, which has an open top, so as to mesh with the rotary blade 11. A large number of elongated holes are formed in a staggered pattern on the bottom surface of the casing 25 to allow the chips 21 to fall downward after cutting. A collection box, a recovery conveyor, etc. (not shown) for collecting the chips 21 after cutting are arranged below the casing 25.

[0017] 3 and 4, the rotary blade 11 is composed of a large diameter blade 29 fitted onto a drive shaft 27 that is driven and rotated by a motor 17 that can rotate forward and backward, and a small diameter blade 31 that has a smaller diameter than the large diameter blade 29. One end of the drive shaft 27, which is rotatably supported by a casing 25 of the cutting unit 15, forms a connecting portion 27a to the reducer 19. With one restricting flange 33A that restricts axial positional deviation of the rotary blade 11 fixed to the connecting portion 27a, the large diameter blades 29 and the small diameter blades 31 are alternately fitted into the other end 27b. An axially extending key (not shown) is attached to the drive shaft 27, and the large diameter blade 29 and the small diameter blade 31 are inserted through their respective key grooves (not shown) so that they cannot rotate around the axis (anti-rotation state).

[0018] Once the predetermined number of large diameter blades 29 and small diameter blades 31 have been inserted, the other regulating flange 33B, which regulates axial positional deviation of the rotary blade 11, is fixed to the other end 27b. This forms the rotary blade 11 in which the large diameter blades 29 and small diameter blades 31 are arranged alternately. The axial width H of the rotary blade 11 can be changed to, for example, 200 mm, 300 mm, 400 mm, or 500 mm in accordance with changes in the width of the chip conveyor 23.

[0019] As shown in FIG. 5, the large diameter blade 29 has a metal annular body 29c having an insertion hole 29a and a key groove 29b for the drive shaft 27, and a plurality of blade portions 29d formed at equal intervals in the circumferential direction on the outer peripheral surface of the annular body 29c. However, the positional relationship between the key groove 29b and the blade portion 29d is not constant, and there are three types of large diameter blades: 29A, 29B, and 29C. Therefore, when all of the large diameter blades are fitted onto the drive shaft 27, the large diameter blades 29A, 29B, and 29C are aligned in the axial direction out of phase with each other. On the other hand, the small diameter blade 31 has a metal annular body 31c having an insertion hole 31a and a key groove 31b for the drive shaft 27, and a plurality of blade portions 31d formed at equal intervals in the circumferential direction on the outer peripheral surface of the annular body 31c. However, the positional relationship between the key groove 31b and the blade portions 31d is constant, and when fitted onto the drive shaft 27, the rows of small diameter blades 31, 31, ... are aligned in the axial direction and in phase with each other.

[0020] The large diameter blades 29 and the small diameter blades 31 are alternately fitted onto the drive shaft 27. The outwardly protruding end of the blade portion 31d of the small diameter blade 31 is substantially flush with the outer circumferential surface of the annular body 29c of the large diameter blade 29, and when viewed in the axial direction, the small diameter blade 31 is substantially contained within the annular body 29c of the large diameter blades 29A, 29B, and 29C. For the large diameter blade 29, the area centered on the concave portion formed between the flank face of the leading blade portion 29d in the circumferential direction of rotation and the rake face of the rear blade portion 29d is the retraction area X of the large diameter blade 29 on the rake face side, and the cross section perpendicular to the axial direction between the leading blade portion 29d and the rear blade portion 29d is an inverted trapezoid. When the phases of the large diameter blades 29, 29, ... lined up in the axial direction are aligned, these inverted trapezoids are connected in the axial direction, making retraction easier. On the other hand, if the phase is shifted, this inverted trapezoid approaches a V shape, making it difficult to pull in. This is because the width W of the attraction region X narrows as the shape approaches the V-shape from the inverted trapezoid. However, the phases of the large diameter blades 29A, 29B, and 29C are adjusted so that no matter how they are arranged next to each other, the cross section of the retraction area X at their boundary is ensured to be a V-shaped concave surface, and a minimum retraction is ensured.

[0021] As shown in Fig. 2, the fixed blade 13 is fixed to the inner surface of the casing 25 of the cutting unit 15 by a fixing screw (not shown). As shown in Fig. 6, the fixed blade 13 has a long block-shaped main body 37 extending parallel to the drive shaft 27, and a recess 37a formed on the side of the main body 37 facing the rotary blade 11, into which the cutting portion 29d of the large diameter blade 29 fits, and a protrusion 37b adjacent to which the cutting portion 31d of the small diameter blade 31 is located. Reference numeral 37c denotes an insertion hole for the fixing screw. The recessed portions 37a and the protruding portions 37b are arranged alternately in the axial direction of the drive shaft 27 in accordance with the shape of the rotary blade 11, forming a comb-like shape. This fixed blade 13 is a general-purpose blade that has been conventionally used in chip crushers.

[0022] 7 is a plan view showing a portion of the meshing state between the rotary blade 11 and the fixed blade 13. As described above, the blade portions 29d, 31d of the large diameter blade 29 and the small diameter blade 31 are offset in the direction around the axis of the drive shaft 27, but for ease of understanding, they are shown here as having no phase difference. Chips 21 supplied from the hopper 9 fall onto the rotary blade 11, but tend to come into contact with the large diameter blade 29 first, which protrudes upward more than the small diameter blade 31, and are mainly drawn into the fixed blade 13 by the large diameter blade 29. In this way, the large diameter blade 29 has both the function of drawing in chips 21 and the function of cutting in cooperation with the fixed blade 13. In contrast, the small diameter blade 31 mainly has the function of cutting in cooperation with the fixed blade 13. Although the large diameter blades 29A, 29B, and 29C are in different phases, all of them can achieve the state shown in Figure 7. In other words, a general-purpose product can continue to be used as the fixed blade 13. Furthermore, with regard to the rotary blade 11, if a problem occurs with the large diameter blade 29 or the small diameter blade 31, it can be solved by simply replacing that blade.

[0023] Since the large diameter blades 29A, 29B, and 29C can be individually inserted into the drive shaft 27, the arrangement pattern of the large diameter blades 29 in axially out-of-phase arrangement can be set arbitrarily. For example, when the large diameter blades are arranged in the order of large diameter blade 29A-large diameter blade 29B-large diameter blade 29A-large diameter blade 29C-large diameter blade 29A, as in arrangement pattern (1) of Fig. 8, the width W is intermittently narrowed. When the large diameter blades are arranged in the order of large diameter blade 29A-large diameter blade 29A-large diameter blade 29C-large diameter blade 29C-large diameter blade 29A-large diameter blade 29A-large diameter blade 29B-large diameter blade 29B-large diameter blade 29A-large diameter blade 29A, as in arrangement pattern (2) of Fig. 9, the width W is widened between large diameter blades 29A-large diameter blade 29A of the same phase. Furthermore, when the blades are arranged in the order of large diameter blade 29B-large diameter blade 29B-large diameter blade 29B-large diameter blade 29A-large diameter blade 29A-large diameter blade 29A-large diameter blade 29C-large diameter blade 29C-large diameter blade 29C-large diameter blade 29A-large diameter blade 29A-large diameter blade 29B-as in arrangement pattern (3) of FIG. 10, the wider width W is ensured for a longer period between large diameter blade 29A-large diameter blade 29A-large diameter blade 29A of the same phase. In addition, by providing three types of large diameter blades, 29A, 29B, and 29C, the width W of each boundary is also divided into wide and narrow.

[0024] The chip crusher 1 is configured as described above, and the chips 21 are curled and are caught by the blade portion 29d of the large diameter blade 29, and are drawn toward the annular body 29c, while being caught between the fixed blade 13 and cut. If the cutting edges 29d, 29d, ... are aligned in phase, when a large number of chips 21, 21, ... fall in a lump at once, they are caught by the row of cutting edges 29d, 29d, ... at the same time and are drawn into and contained in the draw-in area X of a uniform wide width W, which is likely to result in an overload state. If an overload state occurs, the motor 17 is stopped once and then driven in the reverse direction, but there are cases where it is still not possible to process all the chips.

[0025] In contrast, when the phases are shifted as in arrangement patterns (1), (2), and (3), even when a large number of chips 21, 21, ... fall in clumps at once, the rows of upward-facing cutting edges 29d, 29d, ... are thinned out, so the load is dispersed. Moreover, as described above, the general-purpose fixed blade 13 can be used as is. However, chips 21 will not be pulled in unless they are drawn into and contained within the drawing-in area X. By shifting the phase of the large diameter blade 29, the cross section of the drawing-in area X becomes closer to a V-shape and the width W becomes narrower, making it difficult for chips to enter there, so even if they do get caught, they will end up floating above. However, this can be solved by setting an appropriate arrangement pattern that achieves an optimal balance between load distribution and ease of drawing in, depending on conditions such as the shape and size of the chips 21.

[0026] For example, if the chips 21 are fluffy and cotton-like (21a), they are likely to get caught, and once caught, the caught part is likely to be drawn into the drawing-in area X. Therefore, the arrangement pattern (1) is suitable, as it gives priority to not drawing in an excessive amount all at once. On the other hand, if the chips 21 are loosely curled (21b), they are easily drawn in if caught at one point, and are easily contained in the drawing-in area X, so arrangement pattern (2) is suitable. When the chips 21 are severely curled (21c), they are difficult to catch and even if they do catch, they are difficult to retract. Therefore, an arrangement pattern (3) is suitable in which the phase of the cutting portions 29d is aligned to a certain extent, so that the chips can be reliably caught and retracted at multiple hooking points, and a wide retraction area X with a width W is secured for a certain length in the axial direction. If an exchange table is created by previously determining the optimum relationship between the optimum arrangement pattern and the conditions of the chips 21 through experiments, there is an advantage that the operator does not need to have experience or skill.

[0027] Although the embodiments of the present invention have been described in detail above, the specific configuration is not limited to these embodiments, and the invention also includes design changes within the scope of the present invention without departing from the gist of the present invention. For example, the rotation prevention structure of the large diameter blade 29 and the small diameter blade 31 relative to the drive shaft 27 may be a spline connection rather than a connection between a key and the respective key grooves 29b, 31b. The shapes of the blade portion 29d of the large diameter blade 29 and the corresponding recessed portion 37a of the fixed blade 13, and the shapes of the blade portion 31d of the small diameter blade 31 and the corresponding protruding portion 37b of the fixed blade 13 are also not limited to those described above. Furthermore, the numbers of the blade portions 29d and 31d of the large diameter blade 29 and the small diameter blade 31 are not limited to those mentioned above. Furthermore, although an orthogonal shaft type is used for the reducer 19 in each of the above embodiments, a serial type may also be used. Also, a configuration may be adopted in which the rotation speed of the drive shaft 27 is changed in multiple stages by an inverter. [Explanation of symbols]

[0028] 1... Chip crusher 7... Chip crusher body 11...Rotary blade 13...Fixed blade 15...Cutting part 17...Motor 27...Drive shaft 29A, 29B, 29C...Large diameter blade 31...Small diameter blade 37a...concave portion 37b...convex portion X: Retraction area W: Width

Claims

1. A chip crusher comprising: a rotary blade in which large diameter blades and small diameter blades are alternately fitted and detachably attached to a drive shaft that is rotationally driven by a motor; and a fixed blade having a recess into which the large diameter blades fit and a protrusion to which the small diameter blades are adjacent, wherein the rotary blade and the fixed blade cut chips, The phases of the rows of small diameter blades are aligned, and the phases of the rows of large diameter blades are arranged in an arbitrarily set phase-shifted arrangement pattern, in the axial direction of the drive shaft. A chip crusher.

2. The chip crusher according to claim 1, This chip crusher is characterized in that even when the phases of large diameter blades arranged adjacent to each other in the axial direction are shifted, the cross section of the pull-in area perpendicular to the axial direction at the boundary between the blades is ensured to be a V-shaped concave surface.

3. The chip crusher according to claim 1 or 2, This chip crusher is characterized by being composed of a combination of three types of large diameter blades with different phases.

4. The chip crusher according to any one of claims 1 to 3, A chip crusher characterized by large diameter blades arranged in a periodically changing phase.

5. A chip crusher according to any one of claims 1 to 4, A chip crusher characterized in that the number of cutting portions of the large diameter blades and the number of cutting portions of the small diameter blades are the same.

6. A chip crusher according to any one of claims 1 to 5, Each of the large diameter blade and the small diameter blade has an annular body and a plurality of blade portions formed at equal intervals in the circumferential direction on the outer peripheral surface of the annular body, A chip crusher characterized in that the small diameter blade is substantially contained within the annular body of the large diameter blade.

7. A method for cutting chips using a chip crusher according to any one of claims 1 to 6, This cutting method is characterized by preparing multiple types of large diameter blades with different phases, and using a rotary blade with the phase arrangement pattern of the large diameter blades aligned in the axial direction adjusted depending on the conditions of the cutting chips.

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