JP7712388B2 - Fluid ejection head and fluid ejection device - Google Patents

Description

The present invention relates to a fluid ejection head and a fluid ejection device.

In recent years, with the improvement of processing technology, it has become possible to perform precise cutting processing on workpieces (materials to be cut). For example, the inner diameter processing of a workpiece is performed by fixing the workpiece to the chuck of the spindle, placing the cutting edge of the bit set on the tool rest against the inner surface of the workpiece, and rotating the spindle. In the inner diameter processing of a workpiece, cutting chips generated during processing enter the inside of the workpiece. Therefore, there is a demand to prevent cutting chips generated during the inner diameter processing 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 sheet or paper material must be placed as a sealing member 300 inside the workpiece 200 fixed to the chuck 12 of the spindle 11 of the NC lathe processing machine, deeper than the cutting edge of the bit 19, and the sealing must be performed while temporarily fixing it with paper tape 400. Such sealing work requires detailed and sophisticated technology, making it difficult to automate, which is one of the factors that make it difficult to fully automate the inner diameter processing of the workpiece.

In order to realize unmanned production of workpieces that require internal diameter machining, it is desirable to prevent cutting chips from penetrating into the workpiece during internal diameter machining.

A fluid injection device according to one aspect of the present disclosure has a fluid injection head. The fluid injection head includes a shaft portion having an internal fluid flow path for discharging chips generated during internal machining of a workpiece with 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 to the center line of the shaft portion and toward the other end of the shaft portion.

According to one aspect of the present disclosure, it is possible to prevent chips from penetrating into the workpiece during internal diameter machining, thereby enabling unmanned production of workpieces that require internal diameter machining.

FIG. 1 is a diagram showing an example of an NC lathe machine equipped with a fluid ejection device according to this embodiment. FIG. 2 is a side view showing the fluid ejection head of the fluid ejection device according to this embodiment. FIG. 3 is a perspective view of the fluid ejection head of FIG. 2 as viewed obliquely from behind. FIG. 4 is an exploded perspective view of the fluid ejection head of FIG. FIG. 5 is a plan view showing the diffusion plate of FIG. FIG. 6 is a cross-sectional end view taken along line A-A' of FIG. FIG. 7 is an enlarged vertical cross-sectional view of the tip of the fluid ejection head shown in FIG. 2, showing the direction of fluid flowing inside the fluid ejection head. FIG. 8 is a side view showing a state in which the fluid ejecting device according to this embodiment is in use. FIG. 9 is a plan view showing a first modified example of the diffusion plate of FIG. FIG. 10 is a plan view showing a second modified example of the diffusion plate of FIG. FIG. 11 is a diagram showing the positional change in the flow rate of the fluid jetted from the outer periphery of the head portion and the time change at a specific position when the diffusion plates of FIG. 5, FIG. 9 and FIG. 10 are used, respectively. FIG. 12 is a diagram showing a conventional example.

Hereinafter, a fluid ejection 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 designated by the same reference numerals, and repeated explanations will be given only when necessary.

1, the fluid injection device 20 according to this embodiment includes a fluid injection head 21 for discharging chips generated during internal diameter machining of a workpiece using 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 to change the flow rate or flow speed 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.

The fluid injection device 20 is equipped, for example, to an NC lathe machine 1 capable of machining the inner diameter of a workpiece. Specifically, as shown in FIG. 1, a stage 16 movable in the Z direction is provided at a predetermined interval in a position facing the spindle 11 of the NC lathe machine 1 equipped with a chuck 12 for fixing the workpiece, and a fluid injection head 21 is installed on the stage 16. The fluid injection head 21 has an appearance like a circular tube with 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. In the NC lathe machine 1, a plurality of cutting tools 19 for cutting the workpiece are accommodated in the tool rests 14 and 15. The tool rests 14 and 15 are movable along two or three orthogonal axes in the X and Z directions.

2 and 3, the fluid ejection head 21 includes a shaft portion 30 having an internal fluid flow path, and a disk-shaped head portion 40 that is provided at one end (tip) of the shaft portion 30 and ejects the fluid supplied from the shaft portion 30 in a direction that is inclined from the outer periphery toward the center line CL of the shaft portion 30 and toward the other end (rear end) of the shaft portion 30. In this embodiment, the direction toward one end side (tip side) of the shaft portion 30 is appropriately referred to as the front, and the direction toward the other end side (rear end) of the shaft portion 30 is appropriately referred to as the rear.

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

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 disk shape that covers the diffusion plate 60. The bottom plate 50, the diffusion plate 60, and the cover 90 are arranged from the rear so that their central 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 distance from the bottom plate 50. The resulting gap between the diffusion plate 60 and the bottom plate 50 corresponds to the flow path of the fluid 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 periphery of the diffusion plate 60 and the outer periphery of the bottom plate 50 constitutes the discharge port 45 provided in the head portion 40. The discharge port 45 is open toward the rear. In reality, as described below, a plurality of partition plates 61 reaching the outer periphery are arranged radially on the surface of the diffusion plate 60, so that the annular outlet port 45 is radially partitioned by the partition plates 61.

In the center of the bottom plate 50, a plurality of holes 55 (blowout ports 55) are provided to communicate the flow path of the shaft portion 30 with the flow path of the head portion 40. The plurality of blowout ports 55 are arranged at equal intervals along the circumferential direction. A cylindrical partition block 54 protruding forward is integrally formed in the center of the bottom plate 50. A groove having a semicircular cross section is formed along the front-rear direction on the outer peripheral surface of the partition block 54 so as not to block the blowout port 55. A cylindrical screw hole block 51 having a shorter diameter than the partition block 54 is integrally formed in the center of the tip surface of the partition block 54. A groove (not shown) is cut out along the circumferential direction on the outer peripheral surface of the screw hole block 51, and an O-ring 52 is fitted into the groove. The O-ring 52 can bring the outer peripheral surface of the screw hole block 51 and the inner peripheral surface of the cover 90 into close contact with each other, and can 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 a bolt 110 is formed on the tip surface of the screw hole block 51. 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 by the bolt 110 and the screw hole 53. A washer 100 is interposed between the bolt 110 and the cover 90. A hole 63 for passing the partition block 54 provided on the bottom plate 50 is formed at the center position of the disk-shaped diffusion plate 60, and a hole for inserting the screw hole block 51 is formed at the center position of the disk-shaped cover 90. The holes formed in the diffusion plate 60 and the cover 90 are necessary for the fastening structure, and are unnecessary if, for example, the entire head portion 40 is integrally formed. In this embodiment, the diffusion plate 60 is formed in an annular shape, but in the assembled state, it forms a disk shape together with the partition block 54.

The diffusion plate 60 is configured not only to direct the fluid supplied from the shaft portion 30 and blown forward along the center line CL from the outlet 55 of the base plate 50 in a direction perpendicular to the center line CL, but also to diffuse the fluid evenly radially and to direct the fluid that has reached the outer periphery in a rearward direction.

Specifically, as shown in FIG. 4 and FIG. 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. In other words, the plurality of partition plates 61 are arranged radially. The partition plates 61 are 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 plates 61 have a length that reaches the outer circumferential edge from the inner periphery (the outer periphery of the screw hole block 51). The thickness of the partition plate 61 near the outer periphery is formed to be thinner than the thickness of the central part. This makes it possible to secure as much circumferential opening area of the discharge port 45 formed on the outer periphery as possible, and to spray the fluid uniformly around the entire circumference of the outer periphery.

The space between the diffusion plate 60 and the bottom plate 50 is radially divided by a partition block 54 provided at the center of the surface of the bottom plate 50 and a plurality of partition plates 61 provided radially on the surface of the diffusion plate 60. In other words, the plurality of partition plates 61 and the partition block 54 can form a plurality of flow paths that taper along the radial direction. One air outlet 55 is provided in each flow path. 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, so that the flow rate of the fluid blown out from the air outlet 55 is approximately the same, and the fluid blown out from the air outlet 55 flows only in the radial direction and does not flow along the circumferential direction, so that the diffusion plate 60 can uniformly diffuse the fluid supplied from the shaft portion 30 radially.

As shown in FIG. 6, the diffusion plate 60 has a surface that is wavy along the radial direction. The crests and valleys of the surface undulations of the diffusion plate 60 are arranged concentrically. The fluid diffused radially by the diffusion plate 60 is pressurized at the crests of the wave where the gap between the diffusion plate 60 and the bottom plate 50 narrows, and is depressurized at the valleys of the wave where the gap between the diffusion plate 60 and the bottom plate 50 widens. In this way, by undulating the surface of the diffusion plate 60 in a wavy manner along the radial direction (radial direction), the fluid diffused radially by the diffusion plate 60 is rectified while repeatedly pressurized and depressurized along the surface of the diffusion plate 60, and reaches the outer periphery. The shape of the surface of the diffusion plate 60 also contributes to uniformly diffusing the fluid radially.

As shown in FIG. 6, the undulating waves on the surface of the diffusion plate 60 in the radial direction are formed to form mountains at the outer periphery of the diffusion plate 60. As a result, as shown in FIG. 8, the fluid that has reached the outer periphery of the diffusion plate 60 can be discharged from the outlet 45 that opens toward the rear in a direction inclined toward the center line toward the rear. Moreover, the waves formed on the surface of the diffusion plate 60 can make the flow path near the outer periphery of the diffusion plate 60 (the gap between the bottom plate 50 and the diffusion plate 60) narrower than the flow path near the center of the diffusion plate 60 (the gap between the bottom plate 50 and the diffusion plate 60). As a result, the pressure of the fluid sprayed from the outlet 45 can be increased, and the cutting chips generated during the inner diameter machining of the workpiece can be discharged with force.

In this way, by giving various functions to the diffusion plate 60, the head unit 40 can be composed of three major plate-shaped parts, the base plate 50, the diffusion plate 60, and the cover 90, and the head unit 40 can be made thinner. This prevents the head unit 40 from interfering with the cutting edge of the bit when machining the internal diameter of a workpiece, and allows it to be used for machining the internal diameter of a variety of workpieces.

According to the fluid ejection head 21 described above, the fluid can be ejected 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 ejected forward along the center line CL from the outlet 55 opened in the bottom plate 50. The fluid ejected forward along the center line CL from the outlet 55 of the bottom plate 50 is diffused radially by the diffusion plate 60 in a direction perpendicular to the center line CL. The fluid diffused by the diffusion plate 60 can be ejected backward from the outlet 45 opening toward the rear on the outer periphery of the head portion 40 through the gap between the diffusion plate 60 and the bottom plate 50 in a direction inclined toward the center line CL. That is, the fluid introduced into the inside from the rear of the shaft portion 30 flows forward inside the shaft portion 30, is turned back at the head portion 40, and is ejected backward from the outer periphery of the head portion 40.

The fluid injection head 21 is configured to have a disk-shaped head portion 40 at the tip of the rod-shaped shaft portion 30, so that the fluid injection head 21 can be easily inserted into the hole of the workpiece 200 without impeding the movement of tools, etc. As shown in FIG. 8, when machining the inner diameter of the workpiece 200, the fluid injection head 21 is moved by the stage 16 so that the disk-shaped head portion 40 at the tip is inserted into the hollow of the workpiece 200 and is positioned deeper than the cutting edge of the bit 19 for machining the inner diameter. Then, in conjunction with the start of machining the inner diameter of the workpiece 200, the supply of compressed fluid to the fluid injection head 21 is started, and the compressed fluid is injected from the outer periphery of the head portion 40 at the tip of the fluid injection head 21 toward the rear in a direction inclined toward the center line CL. As a result, the chips 201 generated during machining the inner diameter of the workpiece 200 can be discharged from the inside of the workpiece 200 to the outside toward the rear by the fluid. In this way, the fluid ejection device 20 according to this embodiment functions as an air seal device and can prevent chips 201 generated during the internal diameter machining of the workpiece 200 from penetrating into the workpiece 200. In addition, since the fluid ejection device is a non-contact device that ejects compressed fluid, manual sealing work and sensory inspection are not required, and unmanned production of workpieces requiring internal diameter machining can be realized.

In this embodiment, as shown in Fig. 5, the surface of the diffusion plate 60 is formed into a corrugated shape that rises and falls along the radial direction, and further, a plurality of partition plates 61 are provided radially on the surface of the diffusion plate 60. As a result, as shown in Fig. 11(a), the flow rate of the fluid injected from the outer periphery of the head portion 40 can be made uniform over the entire circumference, and the change over time of the flow rate at a specific angular position can be made small, so that chips generated during machining of the inner diameter of the workpiece can be stably discharged over the entire circumference of the inner diameter of the workpiece.

However, the configuration of the diffuser plate 60 is not limited to this embodiment. For example, as shown in FIG. 9, the multiple partition plates 71 radially provided on the surface of the diffuser plate 70 may not be provided to the outer periphery of the diffuser plate 70. When the diffuser plate 70 shown in FIG. 9 is used, for example, as shown in FIG. 11(b), the position change of the flow rate of the fluid ejected from the outer periphery of the head unit 40 is larger than when the diffuser plate 60 shown in FIG. 5 is used, and the time change of the flow rate of the fluid at a specific angular position of the outer periphery is also larger. However, the use of such a diffuser plate 70 is not completely denied. Similarly, as shown in FIG. 10, the diffuser plate 80 may not have a partition plate. When the diffuser plate 80 shown in FIG. 10 is used, for example, as shown in FIG. 11(c), the position change of the flow rate of the fluid ejected from the outer periphery of the head unit 40 and the time change of the flow rate of the fluid at a specific angular position of the outer periphery are larger and more random than when the diffusers 60 and 70 shown in FIG. 5 and FIG. 10 are used. However, the use of such a diffuser plate 80 is not completely denied. In particular, the diffusion plate 80 shown in FIG. 10 has a simple shape and may therefore be superior to the diffusion plate 60 shown in FIG. 5 in terms of making the head portion 40 thinner and in terms of manufacturing costs.

If the only consideration is to diffuse the fluid blown forward along the center line CL from the outlet 55 opened in the bottom plate 50 in a direction perpendicular to the center line, the diffusion plate 60 may be a simple circular plate without a corrugated surface and without a partition plate 61.

In this embodiment, the diffuser plate 60 and the like are constructed based on the design concept that the fluid sprayed from the outer periphery of the head portion 40 is uniform over the entire circumference and does not change over time. However, by varying the flow rate of the fluid sprayed from the outer periphery of the head portion 40 over time, it is possible to vary the strength of the fluid spray, which may make it possible to effectively discharge chips generated during the internal machining of the workpiece from the inside to the outside. The change in the fluid flow rate over time can be achieved by controlling the compressor 23 by the control device 25.

By changing the flow rate of the fluid sprayed from the outer periphery of the head portion 40 at each position on the outer periphery, the fluid can be sprayed in a vortex shape from the entire head portion 40, which may effectively expel chips generated during the internal machining of the workpiece from the inside to the outside. In such a case, it is also effective to use a diffuser plate 70, 80, as shown in Figures 9 and 10, in which the flow rate of the fluid changes depending on the position on the outer periphery of the head portion 40.

In this embodiment, the head unit 40 does not rotate relative to the workpiece, but may be configured to rotate relative to the workpiece. For example, the head unit 40 is provided rotatably relative to the shaft unit 30 by a bearing or the like, and the rotation of the head unit 40 is driven by a motor built into the shaft unit 30 or the head unit 40, so that the head unit 40 can rotate relative to the shaft unit 30. Of course, the stage 16 on which the fluid ejection head 21 is installed in the NC lathe processing machine 1 or a part of the stage 16 may be configured to rotate around the center line CL (Z axis in FIG. 1) of the shaft unit 30. By rotating the head unit 40 in this way, even if a diffusion plate 70, 80 in which the flow rate of the fluid changes depending on the angular position of the outer periphery of the head unit 40 as shown in FIG. 9 and FIG. 10 is used, the disadvantage of the flow rate of the fluid being uneven over the entire circumference can be eliminated. In addition, by deliberately using diffusers 70, 80 in which the fluid flow rate varies depending on the angular position of the outer peripheral edge, it becomes possible to spray the fluid in a vortex shape or the like from the entire head portion 40, as described above, and since the strength (speed) of the fluid spray can be varied, it is possible to effectively expel chips generated during internal machining of the workpiece from the inside to the outside.

In this embodiment, the head unit 40 is configured to be disk-shaped so as to match the hollow cross-sectional shape of the workpiece, but the shape of the head unit 40 is not limited to a disk shape. For example, if the hollow cross-sectional shape of the workpiece is rectangular, the head unit 40 may be rectangular. In this case, for example, the head unit 40 or the fluid ejection head 21 is configured to rotate in synchronization with the rotation of the workpiece.

In this embodiment, the diffusion plate 60 has a structure for uniformly flowing the fluid radially, but the bottom plate 50 may have that structure. In this case, the surface of the bottom plate 50 is formed into a corrugated shape that rises and falls along the radial direction, and a plurality of partition plates 61 are provided radially on the surface of the bottom plate 50. The structure for uniformly flowing the fluid radially may be distributed between the bottom plate 50 and the diffusion plate 60. In this case, the surface of the diffusion plate 60 is formed into a corrugated shape, and a plurality of partition plates 61 are provided radially on the surface of the bottom plate 50.

In this embodiment, by making the diffusion plate 60 slightly larger than the bottom plate 50, a gap is generated between the outer periphery of the bottom plate 50 and the outer periphery of the diffusion plate 60, and this gap can be used as the discharge port 45 that opens toward the rear. However, as long as the fluid diffused radially in a direction perpendicular to the center line CL by the diffusion plate 60 can be sprayed toward the rear from the outer periphery, 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, and a circular slit may be opened along the concentric shape of the bottom plate 50 at a position close to the outer periphery of the bottom plate 50, and this slit may be used as the discharge port 45.

Although several 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, substitutions, and modifications can be made without departing from the gist of the invention. These embodiments and their modifications are within the scope of the invention and its equivalents as set forth in the claims, as well as the scope and gist of the invention.

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 (6)

A fluid injection head for discharging chips generated during the internal machining of a workpiece using a fluid,
A shaft portion having a flow path for the fluid therein;
a disk-shaped head portion provided at one end of the shaft portion and configured to eject the fluid supplied from the shaft portion in a direction inclined to a center line of the shaft portion and toward the other end of the shaft portion ;
The head portion is
A disk-shaped bottom plate connected to one end of the shaft portion;
a disk-shaped diffusion plate disposed at a position facing the bottom plate,
a circular discharge port is formed between the bottom plate and the diffusion plate,
The diffusion plate has a surface that is wavy along a radial direction.
Fluid injection head. The fluid ejection head according to claim 1 , wherein the corrugations are formed such that outer edges of the diffusion plate form peaks of the corrugations. 3. The fluid ejection head according to claim 1 , wherein the diffusion plate has a plurality of partition plates arranged at equal intervals in a circumferential direction to assist the fluid in radial diffusion. The fluid ejection head according to claim 3 , wherein the partition plate is provided up to an outer periphery of the diffusion plate. The fluid ejection head according to claim 3 , wherein the partition plate is provided to a position inside an outer periphery of the diffusion plate. A fluid ejection head according to any one of claims 1 to 5 ,
a fluid supplying device that compresses the fluid and supplies it to the fluid ejection head;
a control device that controls the fluid supply device to change at least one of a flow rate and a flow velocity of the fluid supplied from the fluid supply device to the fluid ejection head;
A fluid ejection device comprising: