Fluid ejection head and fluid ejection device

Abstract

The purpose of the present invention is to prevent chip from entering the inside of a workpiece during inner diameter machining of the workpiece, to achieve unmanned production of workpieces that need inner diameter machining. A fluid jetting apparatus 20 has a fluid jetting head 21. To discharge chip produced during inner diameter machining of a workpiece using a fluid, the fluid jetting head is provided with: a shaft portion 30 provided with a fluid passage therein; and a disc-shaped head portion 40 that is provided on one end of the shaft portion and that jets a fluid supplied from the shaft portion,in a direction inclined to the center line of the shaft portion and toward the other end of the shaft portion.

Description

Technical Field

[0001] The present invention relates to a fluid injection head and a fluid injection device.

Background Art

[0002] In recent years, with the improvement of processing technology, precise cutting of a workpiece (workpiece to be machined) has become possible. For example, in the inner diameter machining of a workpiece, the workpiece is fixed to a chuck of a spindle, the cutting edge of a tool installed on a tool rest is applied to the inner surface of the workpiece, and the spindle rotates to perform the machining. In the inner diameter machining of a workpiece, chips generated during machining enter the inside of the workpiece. Therefore, there is a demand to prevent chips generated during inner diameter machining of the workpiece from entering the inside of the workpiece. Conventionally, in such a case, as shown in FIG. 12, a general-purpose member such as a rubber plate or a paper material is disposed as a sealing member 300 inside the workpiece 200 fixed to the chuck 12 of the spindle 11 of an NC lathe, at a position deeper than the cutting edge of the tool 19, and caulking is required while temporarily fixing with a paper tape 400. Since such caulking work requires a finely refined technique, it is difficult to automate, which is one of the reasons making it difficult to fully automate the inner diameter machining of the workpiece.

Summary of the Invention

Problems to be Solved by the Invention

[0003] In order to realize unmanned production of a workpiece that requires inner diameter machining, it is desired to prevent chips from entering the inside of the workpiece during inner diameter machining of the workpiece.

Means for Solving the Problems

[0004] A fluid injection device according to an aspect of the present disclosure includes a fluid injection head. The fluid injection head includes a shaft portion having a fluid flow path inside for discharging chips generated during inner diameter machining of a workpiece by a fluid, and a disk-shaped head portion provided at one end of the shaft portion for injecting the fluid supplied from the shaft portion in a direction inclined with respect to the center line of the shaft portion and toward the other end of the shaft portion.

Advantages of the Invention

[0005] According to one aspect of the present disclosure, it is possible to prevent chips from entering the inside of the workpiece during inner diameter machining of the workpiece, and it is possible to realize unmanned production of workpieces that require inner diameter machining.

Brief Description of the Drawings

[0006]

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Figure 12

Embodiments for Carrying Out the Invention

[0007] Hereinafter, a fluid injection device according to an embodiment of the present invention will be described with reference to the drawings. In the following description, components having substantially the same functions and configurations are denoted by the same reference numerals, and duplicate explanations will be made only when necessary.

[0008] As shown in FIG. 1, a fluid injection device 20 according to the present embodiment includes a fluid injection head 21 for discharging chips generated during inner diameter machining of a workpiece by a fluid, a compressor 23 for compressing a fluid supplied from the outside and supplying it to the fluid injection head 21, and a control device 25 for controlling the compressor 23 in order to change the flow rate or flow velocity of the fluid supplied from the compressor 23 to the fluid injection head 21. Typically, air or cutting fluid can be used as the fluid.

[0009] The fluid injection device 20 is equipped, for example, on an NC lathe 1 capable of performing inner diameter machining of a workpiece. Specifically, as shown in FIG. 1, a stage 16 movable in the Z direction is provided at a position facing the spindle 11 of the NC lathe 1 having a chuck 12 for fixing the workpiece, with a predetermined interval therebetween, and the fluid injection head 21 is installed on this stage 16. The fluid injection head 21 has an appearance like a circular tube body having an outward flange at the tip, and is fixed to the stage 16 so that the center line of the circular tube is parallel to the Z axis. The NC lathe 1 houses a plurality of cutting tools 19 for cutting the workpiece in the tool posts 14 and 15. The tool posts 14 and 15 are movable along two or three orthogonal axes in the X and Z directions.

[0010] As shown in FIGS. 2 and 3, the fluid injection head 21 includes a shaft portion 30 having a fluid flow path therein, and a disk-shaped head portion 40 provided at one end (tip) of the shaft portion 30 for injecting the fluid supplied from the shaft portion 30 from the outer peripheral edge obliquely toward the center line CL of the shaft portion 30 and in the direction toward the other end (rear end) of the shaft portion 30. In the present embodiment, the direction toward one end side (tip side) of the shaft portion 30 is appropriately used as the front, and the direction toward the other end side (rear end) of the shaft portion 30 is used as the rear.

[0011] As shown in FIG. 4, typically, the shaft portion 30 has a cylindrical shaft body 31. The internal hollow of the shaft body 31 corresponds to the fluid flow path in the shaft portion 30. An inlet 33 for introducing fluid into the interior is provided at the rear end of the shaft body 31.

[0012] The head portion 40 has a bottom plate 50 having a disk shape, a diffusion plate 60 having a disk shape, and a cover 90 having a dish shape covering the diffusion plate 60. The bottom plate 50, the diffusion plate 60, and the cover 90 are arranged in order from the rear such that their center positions coincide with the center line CL of the shaft portion 30. The bottom plate 50 is integrally formed at the tip of the shaft body 31. The diffusion plate 60 is arranged at a predetermined interval from the bottom plate 50. The resulting gap between the diffusion plate 60 and the bottom plate 50 corresponds to the fluid flow path in the head portion 40. The diffusion plate 60 is configured to be slightly larger than the bottom plate 50. The resulting annular gap between the outer peripheral edge of the diffusion plate 60 and the outer peripheral edge of the bottom plate 50 constitutes a discharge port 45 provided in the head portion 40. The discharge port 45 is opened rearward. Actually, as will be described later, since a plurality of partition plates 61 reaching the outer peripheral edge are radially arranged on the surface of the diffusion plate 60, the annular discharge port 45 is radially partitioned by the partition plates 61.

[0013] At the center of the bottom plate 50, a plurality of holes 55 (air outlets 55) are formed to communicate the flow path of the shaft portion 30 and the flow path of the head portion 40. The plurality of air outlets 55 are arranged at equal intervals along the circumferential direction. At the center of the bottom plate 50, a cylindrical partition block 54 protruding forward is integrally formed. On the outer peripheral surface of the partition block 54, a groove having a semicircular cross section is formed along the front-rear direction so as not to block the air outlet 55. At the center of the front end surface of the partition block 54, a cylindrical screw hole block 51 having a diameter shorter than that of the partition block 54 is integrally formed. On the outer peripheral surface of the screw hole block 51, a groove (not shown) is cut out along the circumferential direction, and an O-ring 52 is fitted into the groove. By the O-ring 52, the outer peripheral surface of the screw hole block 51 and the inner peripheral surface of the cover 90 can be brought into close contact with each other, and it is possible to prevent fluid from leaking from the gap between the outer peripheral surface of the screw hole block 51 and the inner peripheral surface of the cover 90. A screw hole 53 for receiving the bolt 110 is formed in the front end surface of the screw hole block 51. By the bolt 110 and the screw hole 53, the diffusion plate 60 is fixed to the bottom plate 50 (that is, the shaft portion 30 integrally formed with the bottom plate 50) together with the cover 90. A washer 100 is interposed between the bolt 110 and the cover 90. At the center position of the diffusion plate 60 having a disc shape, a hole 63 is formed to pass through the partition block 54 provided on the bottom plate 50, and at the center position of the disc-shaped cover 90, a hole for inserting the screw hole block 51 is formed. The holes formed in the diffusion plate 60 and the cover 90 are necessary for the fastening structure, and are unnecessary, for example, if the entire head portion 40 is integrally formed. In the present embodiment, the diffusion plate 60 is configured in an annular shape, but forms a disc shape together with the partition block 54 in the assembled state.

[0014] The diffusion plate 60 is configured not only to flow the fluid supplied from the shaft portion 30 and blown forward along the center line CL from the air outlet 55 of the bottom plate 50 in a direction orthogonal to the center line CL, but also to radially and uniformly diffuse the fluid, and to flow the fluid reaching the outer peripheral edge backward.

[0015] Specifically, as shown in FIGS. 4 and 5, a plurality of partition plates 61 are provided on the surface of the diffusion plate 60. The surface of the diffusion plate 60 refers to the surface facing the bottom plate 50. The plurality of partition plates 61 are arranged at equal intervals along the circumferential direction. That is, the plurality of partition plates 61 are arranged radially. The partition plate 61 is configured to have the same height as the distance from the surface of the diffusion plate 60 to the surface of the bottom plate 50. The partition plate 61 has a length reaching from the inner peripheral edge (the outer peripheral surface of the screw hole block 51) to the outer peripheral edge. The thickness of the partition plate 61 near the outer peripheral edge is formed to be thinner than the thickness of the central portion. Thereby, the circumferential opening area of the discharge port 45 formed at the outer peripheral edge can be ensured as much as possible, and the fluid can be uniformly ejected over the entire circumference of the outer peripheral edge.

[0016] The space between the diffusion plate 60 and the bottom plate 50 is radially partitioned by the partition block 54 provided at the center of the surface of the bottom plate 50 and the plurality of partition plates 61 radially provided on the surface of the diffusion plate 60. That is, a plurality of flow paths that taper and expand along the radial direction can be formed by the plurality of partition plates 61 and the partition block 54. One air outlet 55 is provided in each flow path. Since the plurality of air outlets 55 are arranged at equal intervals on a circle centered on the center line CL of the shaft portion 30, the flow rates of the fluid blown out from the air outlets 55 are substantially the same, and the fluid blown out from the air outlets 55 flows only in the radial direction and does not flow along the circumferential direction. Therefore, the diffusion plate 60 can uniformly diffuse the fluid supplied from the shaft portion 30 in a radial direction.

[0017] Also, as shown in FIG. 6, the diffusion plate 60 has a surface that undulates in a waveform along the radial direction. The peak positions and valley positions of the undulations on the surface of the diffusion plate 60 are arranged concentrically. The fluid radially diffused by the diffusion plate 60 is pressurized at the peak positions of the waveform where the gap between the diffusion plate 60 and the bottom plate 50 becomes narrow, and depressurized at the valley positions of the waveform where the gap between the diffusion plate 60 and the bottom plate 50 becomes wide. In this way, by causing the surface of the diffusion plate 60 to undulate in a waveform along the radial direction (radius direction), the fluid radially diffused by the diffusion plate 60 is rectified while repeating pressurization and depressurization along the surface of the diffusion plate 60 and reaches the outer peripheral edge. The shape of the surface of the diffusion plate 60 also contributes to radially and uniformly diffusing the fluid.

[0018] As shown in FIG. 6, the waveform that undulates along the radial direction on the surface of the diffusion plate 60 is formed to be a peak at the outer peripheral edge of the diffusion plate 60. Thereby, as shown in FIG. 8, the fluid that has reached the outer peripheral edge of the diffusion plate 60 can be discharged from the discharge port 45 that opens rearward in a direction inclined toward the center line rearward. Moreover, due to the waveform formed on the surface of the diffusion plate 60, the flow path (the gap between the bottom plate 50 and the diffusion plate 60) near the outer peripheral edge of the diffusion plate 60 can be made narrower than the flow path (the gap between the bottom plate 50 and the diffusion plate 60) near the center of the diffusion plate 60. Thereby, the pressure of the fluid ejected from the discharge port 45 can be increased, and the chips generated during the inner diameter machining of the workpiece can be vigorously discharged.

[0019] In this way, by endowing the diffusion plate 60 with various functions, the head portion 40 can be composed of three large plate-like components: the bottom plate 50, the diffusion plate 60, and the cover 90, and the head portion 40 can be thinned. Thereby, during the inner diameter machining of the workpiece, it is possible to prevent the head portion 40 from interfering with the cutting edge of the tool, and it can be used for the inner diameter machining of various workpieces.

[0020] According to the fluid injection head 21 described above, fluid can be injected as follows. That is, as shown in FIG. 7, the fluid introduced into the shaft portion 30 flows forward inside the shaft portion 30 and is blown forward along the center line CL from the blowout port 55 formed in the bottom plate 50. The fluid blown forward along the center line CL from the blowout port 55 of the bottom plate 50 is radially diffused by the diffusion plate 60 in a direction perpendicular to the center line CL. The fluid diffused by the diffusion plate 60 can be discharged from the discharge port 45 that opens rearward at the outer peripheral edge of the head portion 40 through the gap between the diffusion plate 60 and the bottom plate 50 in a direction inclined backward with respect to the center line CL. That is, the fluid introduced into the shaft portion 30 from the rear flows forward inside the shaft portion 30, is turned back in the head portion 40, and is ejected rearward from the outer peripheral edge of the head portion 40.

[0021] The fluid injection head 21 is configured in a shape in which a disk-shaped head portion 40 is provided at the tip of a rod-shaped shaft portion 30, so that the fluid injection head 21 can be easily inserted into the hole of the workpiece 200 without hindering the movement of tools or the like. As shown in FIG. 8, when machining the inner diameter of the workpiece 200, the fluid injection head 21 has its disk-shaped head portion 40 at the tip inserted into the hollow of the workpiece 200 and is moved by the stage 16 so as to be disposed at a position deeper than the cutting edge of the cutting tool 19 for inner diameter machining. Then, in accordance with the start of the inner diameter machining of the workpiece 200, the supply of compressed fluid to the fluid injection head 21 is started, and the compressed fluid is ejected from the outer peripheral edge of the head portion 40 at the tip of the fluid injection head 21 rearward in a direction inclined with respect to the center line CL. Thereby, the chips 201 generated during the inner diameter machining of the workpiece 200 can be discharged rearward by the fluid from the inside of the workpiece 200 to the outside. Thus, the fluid injection device 20 according to the present embodiment functions as an air seal device and can prevent the chips 201 generated during the inner diameter machining of the workpiece 200 from entering the inside of the workpiece 200. Further, since the fluid injection device is a non-contact device that blows out compressed fluid, manual plugging work and sensory inspection are not required, and unmanned production of workpieces that require inner diameter machining can be realized.

[0022] In this embodiment, as shown in FIG. 5, the surface of the diffusion plate 60 is formed into a corrugated shape that undulates along the radial direction, and a plurality of partition plates 61 are provided radially on the surface of the diffusion plate 60. Thereby, as shown in FIG. 11(a), the flow rate of the fluid ejected from the outer peripheral edge of the head portion 40 can be made uniform over the entire circumference, and the temporal change in the flow rate at a specific angular position can be reduced, and the chips generated during the inner diameter machining of the workpiece can be stably discharged over the entire circumference of the inner diameter of the workpiece.

[0023] However, the configuration of the diffusion plate 60 is not limited to this embodiment. For example, as shown in FIG. 9, the plurality of partition plates 71 provided radially on the surface of the diffusion plate 70 do not have to be provided up to the outer peripheral edge of the diffusion plate 70. When the diffusion plate 70 shown in FIG. 9 is used, for example, as shown in FIG. 11(b), the positional change in the flow rate of the fluid ejected from the outer peripheral edge of the head portion 40 is larger than when the diffusion plate 60 shown in FIG. 5 is used, and the temporal change in the flow rate of the fluid at a specific angular position on the outer peripheral edge also becomes larger. However, the use of such a diffusion plate 70 is not completely negated. Similarly, as shown in FIG. 10, the diffusion plate 80 does not have to have partition plates. When the diffusion plate 80 shown in FIG. 10 is used, for example, as shown in FIG. 11(c), the positional change in the flow rate of the fluid ejected from the outer peripheral edge of the head portion 40 and the temporal change in the flow rate of the fluid at a specific angular position on the outer peripheral edge are larger and random compared to the cases where the diffusion plates 60 and 70 shown in FIGS. 5 and 10 are used. However, the use of such a diffusion plate 80 is not completely negated. In particular, since the diffusion plate 80 shown in FIG. 10 has a simple shape, it may be superior to the diffusion plate 60 shown in FIG. 5 from the viewpoints of making the head portion 40 thinner and manufacturing cost.

[0024] As long as it is only from the viewpoint of diffusing the fluid blown forward along the center line CL from the air outlet 55 formed in the bottom plate 50 in a direction perpendicular to the center line, the diffusion plate 60 may be a simple disk without a corrugated shape on its surface and without the partition plates 61.

[0025] In this embodiment, with the design concept that the fluid ejected from the outer peripheral edge of the head portion 40 is uniform over the entire circumference and has no temporal change, the diffusion plate 60 and the like are configured. However, by varying the flow rate of the fluid ejected from the outer peripheral edge of the head portion 40 over time, the ejection intensity of the fluid can be made strong or weak, and thereby there is a possibility that the chips generated during the inner diameter machining of the workpiece can be effectively discharged from the inside to the outside of the workpiece. The temporal change in the flow rate of the fluid can be realized by controlling the compressor 23 by the control device 25.

[0026] By changing the flow rate of the fluid ejected from the outer peripheral edge of the head portion 40 at each position of the outer peripheral edge, the fluid can be ejected in a spiral or the like as a whole of the head portion 40, and there is a possibility that the chips generated during the inner diameter machining of the workpiece can be effectively discharged from the inside to the outside of the workpiece. In such a case, it is also effective to use the diffusion plates 70 and 80 in which the flow rate of the fluid changes depending on the position of the outer peripheral edge of the head portion 40 as shown in FIGS. 9 and 10.

[0027] In this embodiment, the head portion 40 does not rotate with respect to the workpiece, but it may be configured such that the head portion 40 rotates with respect to the workpiece. For example, the head portion 40 is rotatably provided with respect to the shaft portion 30 by a bearing or the like, and the rotation of the head portion 40 is driven by a motor built in the shaft portion 30 or the head portion 40, so that the head portion 40 can be rotated with respect to the shaft portion 30. Of course, the stage 16 or a part of the stage 16 where the fluid injection head 21 is installed in the NC lathe 1 may be configured to be rotatable around the center line CL (Z-axis in FIG. 1) of the shaft portion 30. By rotating the head portion 40 in this way, even if diffusion plates 70, 80 in which the flow rate of the fluid changes depending on the angular position of the outer peripheral edge of the head portion 40 as shown in FIGS. 9 and 10 are used, the demerit that the flow rate of the fluid is non-uniform over the entire circumference can be eliminated. Further, by deliberately using diffusion plates 70, 80 in which the flow rate of the fluid differs depending on the angular position of the outer peripheral edge, as described above, the fluid can be ejected in a spiral or the like as a whole of the head portion 40, and the intensity (speed) of the fluid ejection can be made to have a gradual change. Therefore, there is a possibility that the chips generated during the inner diameter machining of the workpiece can be effectively discharged from the inside to the outside of the workpiece.

[0028] In this embodiment, the head portion 40 is configured in a disk shape so as to match the hollow cross-sectional shape of the workpiece, but the shape of the head portion 40 is not limited to the disk shape. For example, if the hollow cross-sectional shape of the workpiece is square, the head portion 40 may be square. In this case, for example, the head portion 40 or the fluid injection head 21 is configured to be rotatable in synchronization with the rotation of the workpiece.

[0029] In this embodiment, the diffusion plate 60 has a structure for uniformly flowing the fluid radially, but the bottom plate 50 may have the structure. In this case, the surface of the bottom plate 50 is formed in a waveform that undulates along the radial direction, and a plurality of partition plates 61 are provided radially on the surface of the bottom plate 50. Further, the structure for uniformly flowing the fluid radially may be dispersed between the bottom plate 50 and the diffusion plate 60. In this case, the surface of the diffusion plate 60 is formed in a waveform, and a plurality of partition plates 61 are provided radially on the surface of the bottom plate 50.

[0030] In this embodiment, by making the diffusion plate 60 slightly larger than the bottom plate 50, a gap is formed between the outer peripheral edge of the bottom plate 50 and the outer peripheral edge of the diffusion plate 60, and this gap can be used as the discharge port 45 that opens rearward. However, if the fluid radially diffused in a direction perpendicular to the center line CL by the diffusion plate 60 can be jetted rearward from the outer peripheral edge, the configuration of the discharge port 45 is not limited to this embodiment. For example, the bottom plate 50 and the diffusion plate 60 may be integrally formed like a box body, and an annular slit may be formed along the concentric circles of the bottom plate 50 at a position close to the outer peripheral edge of the bottom plate 50, and this slit may be used as the discharge port 45.

[0031] Although some embodiments of the present invention have been described, these embodiments are presented as examples and are not intended to limit the scope of the invention. These embodiments can be implemented in various other forms, and various omissions, replacements, and changes can be made without departing from the gist of the invention. These embodiments and their modifications are included in the scope and gist of the invention, and are also included in the invention described in the claims and its equivalent scope.

Explanation of Reference Numerals

[0032] 21... Fluid injection head, 30... Shaft portion, 31... Shaft body, 33... Inlet, 40... Head portion, 50... Bottom plate, 60... Diffusion plate, 90... Cover, 100... Washer, 110... Bolt.

Claims

1. In a fluid injection head for discharging chips generated during inner diameter machining of a workpiece by a fluid, a shaft portion having a fluid flow path therein, a disk-shaped head portion provided at one end of the shaft portion and injecting the fluid supplied from the shaft portion in a direction inclined with respect to the center line of the shaft portion and toward the other end of the shaft portion, wherein the head portion has a disk-shaped bottom plate connected to one end of the shaft portion, and a disk-shaped diffusion plate disposed at a position facing the bottom plate, an annular discharge port is formed between the bottom plate and the diffusion plate, the diffusion plate has a surface that undulates in a waveform along the radial direction, a fluid injection head.

2. The fluid injection head according to claim 1, wherein the waveform is formed such that the outer edge of the diffusion plate becomes the peak of the waveform.

3. The fluid injection head according to claim 1 or 2, wherein the diffusion plate has a plurality of partition plates arranged at equal intervals in the circumferential direction to assist in the radial diffusion of the fluid.

4. The fluid injection head according to claim 3, wherein the partition plates are provided up to the outer peripheral edge of the diffusion plate.

5. The fluid injection head according to claim 3, wherein the partition plates are provided up to a position inside the outer peripheral edge of the diffusion plate.

6. A fluid injection head according to any one of claims 1 to 5, a fluid supply device for compressing the fluid and supplying it to the fluid injection head, and a control device for controlling the fluid supply device to change at least one of the flow rate and the flow velocity of the fluid supplied from the fluid supply device to the fluid injection head. A fluid injection device comprising the above.

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