阅读说明：本技术 喷嘴、喷丸加工装置以及喷丸加工方法 (Nozzle, shot-peening apparatus, and shot-peening method ) 是由 神田真治 于 2020-03-03 设计创作，主要内容包括：本发明涉及喷嘴、喷丸加工装置以及喷丸加工方法,本发明的一个方式所涉及的喷嘴具备：基部,其具有研磨材料的导入路；和前端部,其具有以轴线为中心的圆环状的喷射口。该前端部具有：杆,该杆的至少一部分呈以轴线为中心轴线并且随着接近喷射口而直径变大的圆锥台形状；和喷头,该喷头是具有从杆的侧方包围杆的侧面的内周面的筒状的喷头,在侧面与内周面之间形成将从导入路导入的研磨材料导向喷射口的通路。(The present invention relates to a nozzle, a shot-peening apparatus, and a shot-peening method, and a nozzle according to an embodiment of the present invention includes: a base having an abrasive introduction path; and a tip portion having an annular injection port centered on the axis. The tip portion has: a rod, at least a part of which has a truncated cone shape having an axis as a central axis and a diameter that increases as it approaches the ejection port; and a nozzle having a cylindrical shape and an inner circumferential surface surrounding a side surface of the rod from a side of the rod, wherein a passage for guiding the abrasive introduced from the introduction passage to the ejection port is formed between the side surface and the inner circumferential surface.)

1. A nozzle is characterized by comprising:

a base having an abrasive introduction path; and

a front end portion having an annular jet port centered on an axis,

the tip portion has:

a rod having at least a part thereof in a truncated cone shape having the axis as a central axis and having a diameter that increases as the rod approaches the ejection opening; and

and a nozzle having a cylindrical shape and an inner circumferential surface surrounding a side surface of the rod from a side of the rod, wherein a passage for guiding the abrasive introduced from the introduction passage to the ejection port is formed between the side surface and the inner circumferential surface.

2. The nozzle of claim 1,

the nozzle further includes a main body portion provided between the base portion and the tip portion, and having a diffusion chamber communicating with the introduction passage and a buffer chamber communicating with the passage,

the main body portion has a diffusion plate disposed between the diffusion chamber and the buffer chamber and disposed on the axis,

a plurality of openings are formed in the diffuser plate along an imaginary circle centered on the axis.

3. The nozzle of claim 2,

the base portion includes an introduction pipe extending linearly along the axis and defining the introduction path,

an introduction port to which an end of the introduction pipe is connected is formed in the main body,

the inlet pipe has a length that is 10 times or more the opening width of the inlet.

4. The nozzle according to any one of claims 1 to 3,

the stem and the showerhead are composed of boron carbide.

5. A shot-peening apparatus is characterized in that,

a shot-peening apparatus comprising the nozzle according to any one of claims 1 to 4.

6. A shot peening method for blasting an abrasive from a nozzle having a base portion and a tip portion, wherein the base portion has an abrasive introduction passage and the tip portion has an annular ejection hole centered on an axis,

the shot peening method is characterized by comprising:

introducing the abrasive from the introduction path; and

and ejecting the abrasive from the ejection port in a direction inclined radially to the axis with respect to the axis and away from the axis as the abrasive moves away from the ejection port.

7. The shot peening method according to claim 6,

the nozzle further includes a circular diffuser plate disposed between the base portion and the tip portion and disposed on the axis, the diffuser plate having a plurality of openings formed along a circumferential direction of an imaginary circle centered on the axis,

the method of shot peening further includes a step of causing the abrasive introduced from the introduction passage to collide with the diffusion plate, and causing the collided abrasive to pass through the plurality of openings, thereby diffusing the abrasive.

Technical Field

The present disclosure relates to a nozzle, a shot peening apparatus, and a shot peening method.

Background

There is known a shot peening apparatus in which a hole, a groove, or the like is formed in a target object by ejecting an abrasive together with compressed air from a nozzle. In such shot peening, a dry film having a mask pattern is formed on an object to be processed, and an abrasive is ejected from a nozzle to remove a region of the object exposed from the dry film, thereby forming a space in the object.

A general shot-peening apparatus includes a nozzle as shown in fig. 10. The conventional nozzle 100 shown in fig. 10 ejects an abrasive M from a circular ejection opening 102 to a target object W through a dry film 104. When the space 106 is formed in the object W using the nozzle 100, a tapered surface is formed on the side wall 106s defining the space 106, and the space 106 having a shape tapered toward the tip in the depth direction is formed.

In recent years, depending on the application of shot peening, a space having high verticality is required to be formed in a subject to be processed. As a technique for forming a space having high perpendicularity, a shot peening method described in patent document 1 is known. Patent document 1 describes a technique for forming a groove-like space in a target object by using a nozzle including: a dispersion chamber for dispersing a solid-gas two-phase flow containing a powder and a gas; a converging chamber for converging the solid-gas two-phase flow; and an acceleration chamber that accelerates the converged solid-gas two-phase flow. The ejection opening of the nozzle of patent document 1 has a slit shape. The injection port is divided into two by the center of the slit in the longitudinal direction, and the two divided injection ports are inclined in the longitudinal direction of the injection port with respect to the normal direction of the processing surface of the object to be processed, and inject the solid-gas two-phase flow in directions away from each other.

Patent document 1: japanese patent laid-open No. 2001 and 129762

Disclosure of Invention

In the nozzle described in patent document 1, the abrasive is ejected in a direction inclined in the longitudinal direction of the ejection opening with respect to the normal direction of the processing surface of the object to be processed, and thereby the abrasive collides with the side wall of the defining groove from the inclined direction. In this way, the polishing material collides with the side wall from an oblique direction, thereby removing the tapered surface and improving the perpendicularity of the groove. However, in this nozzle, although the tapered surface of the side wall formed perpendicularly to the longitudinal direction of the slot-shaped ejection opening can be removed, the tapered surface remains on the side wall formed in the direction parallel to the longitudinal direction of the ejection opening. That is, in the shot peening using the nozzle described in patent document 1, the angle of the side wall of the space varies depending on the orientation of the side wall, and the space is formed anisotropically.

Therefore, it is required to provide a nozzle, a shot peening apparatus, and a shot peening method capable of forming a space isotropically and improving the perpendicularity of the space.

A nozzle according to one aspect includes: a base having an abrasive introduction path; and a tip portion having an annular injection port centered on the axis. The front end has a stem and a spray head. At least a part of the rod has a truncated cone shape having an axis as a central axis and a diameter that becomes larger as it approaches the ejection port. The head is cylindrical and has an inner circumferential surface surrounding a side surface of the rod from a side of the rod, and a passage for guiding the abrasive introduced from the introduction path to the ejection port is formed between the side surface and the inner circumferential surface.

In the nozzle according to the above aspect, when the abrasive is introduced from the introduction passage, the abrasive flows into the passage formed between the side surface and the inner peripheral surface of the rod. The abrasive of the inflow passage is guided to the ejection port along a side surface of a truncated cone shape extending around the axis and having a diameter that increases as it approaches the ejection port, and is ejected from the ejection port. Since the abrasive ejected in this way collides with the side wall defining the space from an oblique direction, the tapered surface of the side wall can be removed, and as a result, the perpendicularity of the space can be improved. In the nozzle of the above aspect, since the abrasive is ejected from the annular ejection port in all directions around the axis, the space can be formed isotropically in the object to be processed.

The nozzle of one embodiment may include a main body portion provided between the base portion and the distal end portion. The main body has a diffusion chamber communicating with the introduction passage and a buffer chamber communicating with the passage. The body portion may have a diffuser plate disposed between the diffuser chamber and the buffer chamber and disposed on the axis, and a plurality of openings may be formed in the diffuser plate along an imaginary circle centered on the axis.

In the above embodiment, the polishing material introduced from the introduction path into the diffusion chamber is diffused in the diffusion chamber by colliding with the diffusion plate and rebounding. The diffused abrasive material is introduced into the buffer chamber through the plurality of openings. An abrasive introduction passage for introducing the abrasive into the buffer chamber. By introducing the diffused abrasive into the passage in this manner, the uniformity of the distribution of the abrasive in the discharge port can be improved.

In one embodiment, the base portion may include an introduction tube extending linearly along the axis and defining an introduction path. The body may be provided with an inlet to which an end of the inlet pipe is connected, and the inlet pipe may have a length 10 times or more the opening width of the inlet.

In this embodiment, the introduction pipe extends linearly along the axis and has a sufficient length with respect to the width of the introduction port, so that the abrasive flowing through the introduction passage can be rectified to flow in a direction parallel to the axial direction. As a result, the uniformity of the distribution of the polishing material in the discharge port can be further improved.

In one embodiment, the stem and showerhead may also be constructed of boron carbide. Since boron carbide has high wear resistance, the wear of the stem and the showerhead can be suppressed by forming the stem and the showerhead from boron carbide.

A shot peening device according to one aspect includes the nozzle. As described above, according to the shot peening apparatus, the space can be formed isotropically, and the verticality of the space can be improved.

In one aspect, a shot peening method for peening a polishing material from a nozzle having a base portion and a tip portion, wherein the base portion has an introduction path for the polishing material, and the tip portion has an annular ejection port centered on an axis. The method includes a step of introducing the abrasive from the introduction path, and a step of ejecting the abrasive from the ejection port in a direction inclined to the radial side with respect to the axis, that is, in a direction away from the axis as the ejection port is separated.

In the shot peening method of the above aspect, the abrasive is shot from the injection port in a direction inclined radially to the axis with respect to the axis, that is, in a direction away from the axis as the abrasive moves away from the injection port. Since the abrasive ejected in this way collides with the side wall defining the space from an oblique direction, the tapered surface of the side wall can be removed, and as a result, the perpendicularity of the space can be improved. In the nozzle of the above aspect, since the abrasive is ejected from the annular ejection port in all directions around the axis, the space can be formed isotropically in the object to be processed.

In one embodiment, the nozzle may further include a circular diffusion plate disposed between the base portion and the tip portion and disposed on the axis, the diffusion plate having a plurality of openings formed along a circumferential direction of an imaginary circle having the axis as a center, and the method may further include a step of causing the abrasive introduced from the introduction path to collide with the diffusion plate, and causing the colliding abrasive to pass through the plurality of openings, thereby diffusing the abrasive.

In the above embodiment, the polishing material introduced from the introduction path into the diffusion chamber is diffused by colliding with the diffusion plate and rebounding. The diffused abrasive is ejected from the ejection port through the plurality of openings. In this way, by diffusing the polishing material using the diffusion plate, the uniformity of the distribution of the polishing material in the ejection port can be improved.

According to one embodiment and various embodiments of the present invention, a space can be formed isotropically, and the verticality of the space can be improved.

Drawings

Fig. 1 is a diagram schematically showing a shot peening system according to an embodiment.

Fig. 2 is a sectional view showing a nozzle according to an embodiment.

Fig. 3 is a perspective view showing a nozzle according to an embodiment.

Fig. 4 is a plan view of the diffusion portion.

Fig. 5 is a bottom view of the front end portion.

Fig. 6 is a sectional view showing the flow of the abrasive.

Fig. 7 is a sectional view taken along line VII-VII of fig. 6.

Fig. 8 is a flowchart illustrating a shot peening method according to an embodiment.

FIG. 9 is a cross-sectional view showing an object to be processed having holes formed therein according to experimental examples 1 to 3.

Fig. 10 is a sectional view showing a conventional nozzle.

Description of the reference numerals

1 … shot peening system; 10 … shot-peening device; 12 … container; a 20 … nozzle; 22 … supply pipe; 24 … processing stations; 31 … base part; 32 … a body portion; 33 … front end; 34 … an inlet tube; a 34j … linker; 35 … introduction path; 36 … through holes (inlet); 37 … a top plate; 38 … an upper body; 38s … diffusion chamber; 39 … diffuser portion; 40 … lower body; 41 … a diffuser plate; 42 … a frame body; 43 … a plurality of openings; 44 … cylinder; 44s … buffer chamber; 45 … connecting parts; 46 … a cylinder body; 47 … bar; side 47a …; 48 … spray head; 48a … inner peripheral surface; 48b … inclined plane; 49 … jet orifice; 50 … abrasive material supply means; 62 … classifier; 70 … dust collector; 74 … gap (passage); f … dry film; m … abrasive material; w … target object; the Z … axis.

Detailed Description

Hereinafter, embodiments of the present disclosure will be described with reference to the drawings. In the following description, the same or corresponding elements are denoted by the same reference numerals, and repetitive description thereof will not be repeated. The dimensional ratios in the drawings do not necessarily correspond to the dimensional ratios illustrated. The terms "upper", "lower", "left" and "right" are based on the illustrated states and are for convenience.

Fig. 1 is a diagram schematically showing a shot peening system according to an embodiment. The shot peening system 1 shown in fig. 1 includes a shot peening device 10, an abrasive material supply device 50, a classifier 62, and a dust collector 70.

The shot peening apparatus 10 is an apparatus that jets the abrasive M supplied from the abrasive supply device 50 onto the object W to be processed. The shot peening apparatus 10 jets the abrasive M toward the object W to form a hole, a groove, or other space in the object W. The shot peening device 10 is, for example, a direct pressure type shot peening device.

The shot peening device 10 includes a container 12 and a nozzle 20. The container 12 includes an upper container 13 and a lower container 14. The lower part of the upper container 13 is open, and the upper part of the lower container 14 is open. A pass plate 23 is provided between the upper tank 13 and the lower tank 14. The passage plate 23 is formed with a plurality of openings through which the polishing material M can pass. The upper container 13 defines a processing chamber 13s together with the pass-through plate 23.

A processing table 24 on which the object W to be processed is placed is provided in the processing chamber 13 s. The object W may be a hard and brittle material such as a ceramic material or a glass material, or a hard-to-cut material such as a CFRP (Carbon Fiber Reinforced Plastics) material. The processing table 24 is supported by a conveyance drive unit 25. The conveyance drive section 25 is provided on the pass-through plate 23. The conveyance drive unit 25 is a moving mechanism such as an X-Y table, for example, and moves the object W to be processed placed on the processing table 24 relative to the nozzle 20. The moving direction and moving speed of the object W are appropriately set according to the size, shape, material, shape of the space formed in the object W, and the like of the object W. Further, the upper container 13 may be provided with a window 13w for observing the inside of the processing chamber 13 s.

The nozzle 20 is disposed above the processing table 24. The nozzle 20 is a shot-peening nozzle for direct-pressure peening, and includes a base 31, a body 32, and a tip 33. The front end portion 33 has an ejection port 49 for the abrasive M, and the ejection port 49 is provided in the processing chamber 13s so as to face the upper surface of the processing table 24. The base 31 is at least partially disposed outside the processing chamber 13s, and one end of the supply pipe 22 is connected to the base 31. The nozzle 20 ejects the polishing material M supplied from the supply pipe 22 to the object W as a solid-gas two-phase flow together with compressed air.

A nozzle driving unit 26 is provided above the upper tank 13. The nozzle driving unit 26 includes a connection mechanism connected to the nozzle 20 and a motor for driving the connection mechanism. The nozzle driving unit 26 drives the motor to move the horizontal position of the nozzle 20 relative to the object W placed on the processing table 24. The moving direction and the moving speed of the nozzle 20 by the nozzle driving unit 26 are appropriately set according to the size, shape, material, shape of the space to be formed, and the like of the object W.

The lower container 14 is disposed below the upper container 13. The lower container 14 has a tapered side wall whose width is narrowed downward. The lower container 14 defines a recovery space 14s together with the pass plate 23. The recovery space 14s communicates with the processing chamber 13s via a plurality of openings formed in the pass-through plate 23. Therefore, the abrasive M ejected from the nozzle 20 toward the object W is collected by the collection space 14s of the lower container 14 through the plurality of openings formed in the pass-through plate 23. A lower opening 14e for supplying the collected abrasive M to the classifier 62 is formed in the bottom of the lower container 14.

One end of the recovery pipe 28 is connected to the lower opening 14e of the lower container 14. The other end of the recovery pipe 28 is connected to the classifier 62. The classifier 62 sucks the used abrasive M ejected from the nozzle 20 toward the object W to separate the reusable abrasive M and the non-reusable fragments. The classifier 62 is, for example, a cyclone classifier. One end of the cyclone conduit 64 is connected to the classifier 62. The other end of the cyclone duct 64 is connected to a dust collector 70. The unusable debris in the used abrasive material M drawn to the classifier 62 is conveyed to the dust collector 70 via the cyclone duct 64. On the other hand, reusable abrasive M among the used abrasive M attracted to the classifier 62 is conveyed to the conduit 66.

The dust collector 70 is a device for collecting chips of the abrasive material M and cutting powder of the object W to be processed. The dust collector 70 sucks the cyclone duct 64, and generates an air flow from the lower opening 14e of the lower container 14 through the recovery pipe 28, the classifier 62, and the cyclone duct 64 toward the dust collector 70. By this air flow, the used abrasive M and the cut powder of the object W to be processed collected in the collection space 14s of the lower container 14 are conveyed to the classifier 62, and the dust collector 70 sucks the chips and the cut powder of the abrasive M classified in the classifier 62. A filter is used to capture the debris and cutting powder that are attracted by the dust collector 70.

An abrasive material supply device 50 is provided below the classifier 62. The abrasive supply device 50 is a device for supplying the abrasive M to the shot peening apparatus 10, and includes a tank 52 and a quantitative supply mechanism 54. The grinding material M is stored in the tank 52. Although not limited, as the abrasive material M, for example, alumina powder, pig iron abrasive, and mold abrasive can be used.

The can 52 includes a top plate 52a and a side wall 52 b. In one embodiment, the canister 52 has four sidewalls 52 b. Each of the four side walls 52b has an upper portion disposed in parallel with the opposite side wall 52b and a lower portion inclined so that the opposite side wall 52b approaches downward. That is, the can 52 has a side wall whose width is narrowed downward.

In addition, a lower opening 53 is formed in the bottom of the tank 52. A constant-volume supply mechanism 54 is provided below the lower opening 53 of the tank 52. The other end of the supply pipe 22 is connected to a constant-volume supply mechanism 54. The constant-volume supply mechanism 54 takes out a constant volume of the polishing material M from the lower opening 53 in the tank 52, and supplies the taken-out polishing material to the nozzle 20 via the supply pipe 22.

In one embodiment, the metering mechanism 54 includes a roller 54a and a drive mechanism 54 b. A recess is formed in the outer peripheral surface of the roller 54a, into which the polishing material M supplied from the lower opening 53 in the tank 52 is filled. The driving mechanism 54b rotates the roller 54a by applying a driving force to the roller 54 a. The compressed air supplied from the compressed air supply device 56 is ejected to the recessed portion conveyed downstream in the rotation direction by the rotation of the roller 54a, and the polishing material M filled in the recessed portion is taken out. The polishing material M taken out of the recess is supplied to the nozzle 20 through the supply pipe 22 by compressed air. The quantitative supply mechanism 54 is not limited to the structure including the roller 54a and the drive mechanism 54b, and the structure is not limited as long as a certain amount of the abrasive M can be supplied to the nozzle 20.

A pressurization pipe 58 is connected to the top plate 52a of the tank 52. The pressurized pipe 58 is connected to the compressed air supply device 56. The compressed air supplied from the compressed air supply device 56 is introduced into the tank 52 as pressurized air via a pressurization pipe 58. The pressure in tank 52 is increased by supplying the pressure air into tank 52. By this pressure, the abrasive M in the tank 52 is densely filled into the concave portion of the roller 54a through the lower opening 53.

An opening for collecting the reusable abrasives M classified by the classifier 62 is formed in the top plate 52a of the tank 52. Between this opening and the conduit 66, a valve body 60 is arranged. The valve body 60 is, for example, a pressurizing valve, and opens and closes in accordance with the internal pressure of the tank 52. Specifically, the valve element 60 is closed when the internal pressure of the tank 52 is higher than a predetermined pressure, and is opened when the internal pressure of the tank 52 is equal to or lower than the predetermined pressure. With the valve body 60 closed, the tank 52 is disconnected from the conduit 66, thereby stopping the supply of the abrasive material M from the classifier 62 to the tank 52. Conversely, when the valve body 60 is opened, the tank 52 communicates with the conduit 66, and the reusable abrasive M is supplied from the classifier 62 to the tank 52. In one embodiment, the valve body 60 may be a triangular valve in which a conical valve body is moved up and down by driving of a bleed valve, an air cylinder, or the like, for example.

In one embodiment, the abrasive supplying device 50 may further include a vibrator 55. The vibrator 55 suppresses uneven distribution or residue of the abrasive M in the tank 52 by vibrating the tank 52, and smoothly feeds the abrasive M from the lower opening 53.

In one embodiment, the shot-peening device 10 may further include a control device CNT. The control device CNT is constituted by, for example, a programmable computer, and controls the overall operation of the shot peening system 1. The control device CNT is connected to, for example, the conveyance drive unit 25, the nozzle drive unit 26, the drive mechanism 54b, the classifier 62, and the dust collector 70.

The control device CNT operates according to the input program and transmits a control signal. The moving direction and moving speed of the processing table 24, the moving direction and moving speed of the nozzle 20, the rotational speed of the roller 54a, the operation and stop of the classifier 62, and the operation and stop of the dust collector 70 can be controlled according to a control signal from the control device CNT.

Hereinafter, a nozzle according to an embodiment will be described in detail with reference to fig. 2 and 3. Fig. 2 is a sectional view showing a nozzle 20 according to an embodiment. Fig. 3 is a perspective view showing a nozzle 20 according to an embodiment. As shown in fig. 2 and 3, the nozzle 20 includes a base 31, a body 32, and a tip 33. Hereinafter, the direction of the nozzle 20 toward the base 31 is referred to as the nozzle base end side, and the direction of the nozzle 20 toward the ejection opening 49 is referred to as the nozzle tip end side.

The base 31 is a portion for introducing the polishing material M supplied from the polishing material supply device 50 into the nozzle 20. The base 31 has an introduction pipe 34 extending linearly along the axis Z of the nozzle 20. An introduction passage 35 for the abrasive M is defined inside the introduction pipe 34. A coupling 34j for connection is provided at an end of the introduction pipe 34 on the nozzle base end side, and the introduction pipe 34 is connected to the supply pipe 22 via the coupling 34 j. The end of the introduction pipe 34 on the nozzle tip side is fitted into a through hole (introduction port) 36 formed in the body 32 and connected to the body 32. In one embodiment, the introduction tube 34 may have a length L10 times or more the opening width r of the through hole 36.

The main body 32 includes a top plate 37, an upper body 38, a diffuser 39, and a lower body 40. The upper body 38 has a cylindrical shape, and defines a diffusion chamber 38s therein. The diffusion chamber 38s is a space for diffusing the abrasive M introduced from the introduction path 35, and has a substantially cylindrical shape. A top plate 37 is provided at the end of the upper body 38 on the side of the introduction pipe 34, that is, at the upper end of the upper body 38. The top plate 37 is a plate body having a substantially square planar shape, and covers the upper end of the upper main body 38.

The top plate 37 is formed with a through hole 36 penetrating the top plate 37 in the thickness direction. The through hole 36 is formed at a position overlapping the axis Z. The through hole 36 has a predetermined opening width r in a direction orthogonal to the axis Z. The end of the introduction pipe 34 on the nozzle tip side is fitted into the through hole 36.

A diffuser portion 39 is provided on the nozzle tip side of the upper body 38. The diffuser 39 includes a diffuser plate 41 and a frame 42. The diffuser plate 41 is provided between the diffusion chamber 38s and a buffer chamber 44s described later, and is disposed on the axis Z. In one embodiment, the diffuser plate 41 has a circular plate shape and is disposed along a plane orthogonal to the axis Z. The center of the diffuser plate 41 is disposed at a position overlapping the axis Z.

Fig. 4 is a plan view showing the diffusion portion 39. As shown in fig. 4, the diffusion plate 41 is formed with a plurality of openings 43 through which the polishing material M can pass. These plurality of openings 43 are arranged along an imaginary circle C centered on the axis Z, and are formed at equal intervals about the axis Z. The plurality of openings 43 communicate the diffusion chamber 38s with a buffer chamber 44s described later. In one embodiment, the diffuser plate 41 may be composed of boron carbide.

The frame 42 is provided to surround the diffuser plate 41 from the radial outside. The frame 42 is sandwiched between the upper body 38 and the lower body 40. Thereby, the diffusion plate 41 is held between the diffusion chamber 38s and the buffer chamber 44 s. The diffusion plate 41 and the frame 42 may be formed integrally or may be formed separately and then connected to each other.

As shown in fig. 2, the lower body 40 has a cylindrical body 44 and a coupling member 45. The cylinder 44 is cylindrical in the same shape as the upper body 38, and is provided on the nozzle tip side with respect to the frame 42. The coupling member 45 is provided in the inner space of the cylindrical body 44. In one embodiment, the coupling member 45 includes a circular plate 45a and a protrusion 45 b. The disk 45a has the same shape as the diffuser plate 41, and is disposed on the nozzle tip side of the diffuser plate 41 so as to overlap the diffuser plate 41. That is, the plurality of openings formed in the circular plate 45a are provided at positions overlapping the plurality of openings 43 formed in the diffuser plate 41 as viewed in the direction of the axis Z. The circular plate 45a is connected to the cylinder 44.

The projection 45b has a cylindrical shape with an upper surface and a lower surface. The upper surface of the projection 45b is connected to the disk 45 a. A screw hole through which the screw 72 is inserted is formed in the lower surface of the projection 45 b. The projection 45b extends between the upper surface and the lower surface in such a manner that the central axis thereof coincides with the axis Z.

A buffer chamber 44s is formed between the cylindrical body 44 and the protruding portion 45 b. The buffer chamber 44s has an annular space when viewed in a cross section orthogonal to the axis Z, and extends in a direction parallel to the direction of the axis Z. The diffusion chamber 38s and the buffer chamber 44s communicate with each other via the plurality of openings 43 of the diffusion plate 41 and the plurality of openings of the circular plate 45 a.

Further, holes extending in the axis Z direction may be formed in the top plate 37, the upper body 38, the frame 42, and the cylinder 44, and the top plate 37, the upper body 38, the diffuser 39, and the lower body 40 may be fastened to each other by inserting screws B1 through the holes. In one embodiment, a groove may be formed in an end portion of the upper main body 38 on the nozzle base end side, an elastic body (e.g., an O-ring) R may be provided along the groove, and the top plate 37 and the upper main body 38 may be fastened by the elastic body R.

The tip portion 33 is provided on the nozzle tip side with respect to the body portion 32. The front end portion 33 includes a cylinder 46, a rod 47, and a nozzle 48. The cylinder 46 has a cylindrical shape, and defines a cylindrical inner space therein. The central axis of the cylinder 46 coincides with the axis Z. The cylinder 46 is fixed to the cylinder 44 by a screw B2. In one embodiment, an elastic body (e.g., an O-ring) R may be interposed between the cylinder 44 and the cylinder 46.

A rod 47 and a nozzle 48 are provided in the inner space of the cylinder 46. Although not limited thereto, the rod 47 and the shower head 48 may be made of a material having wear resistance such as boron carbide. The rod 47 has a truncated cone shape having the axis Z as a central axis and having a diameter that increases as it approaches the nozzle tip side. The upper surface of the rod 47 has a diameter equal to or smaller than the diameter of the protrusion 45b, and the lower surface of the rod 47 has a diameter larger than the upper surface. In addition, the lever 47 has a side face 47a inclined with respect to the axis Z. More specifically, the side surface 47a extends along a conical surface that extends along the axis Z and has a diameter that becomes larger as approaching the ejection opening 49 of the nozzle 20.

As shown in fig. 2, in a cross section taken on a plane along the axis Z, the side surface 47a extends linearly in a direction inclined at an angle θ with respect to the axis Z. The angle θ is arbitrarily set according to the size, shape, material, shape of the space to be formed, and the like of the object W. By changing the angle θ, the projection angle of the polishing material M ejected from the ejection port 49 changes, and as a result, the angle of the side wall defining the space can be controlled. In one embodiment, the angle θ may be set to 5 ° to 30 °, and more specifically, may be set to 5 ° to 15 °.

In one embodiment, the rod 47 has a through hole 47h formed along its central axis (axis Z). A screw 72 is inserted into the through hole 47h, and the screw 72 is screwed into a screw hole formed in the projection 45 b. Thus, the lever 47 is fixed to the body portion 32 in a state where the upper surface of the lever 47 faces the lower surface of the projection 45 b.

The head 48 is cylindrical and provided so as to surround the side surface 47a of the rod 47. The head 48 has an inner circumferential surface 48a surrounding the side surface 47a from the side of the rod 47. The inner peripheral surface 48a is disposed to face the side surface 47 a. That is, the side surface 47a and the inner peripheral surface 48a extend parallel to each other as viewed in a cross section including the axis Z. A gap 74 is formed between the side surface 47a and the inner peripheral surface 48 a. The gap 74 extends along the side surface 47a of the rod 47 and has an annular shape when viewed in a cross section orthogonal to the axis Z. When viewed from the cross section shown in fig. 2, the extending direction of the gap 74 is inclined with respect to the axis Z so as to be away from the axis Z as approaching the nozzle tip side. In the direction normal to the side surface 47a, the gap 74 has a width of 1mm, for example. The gap 74 functions as a passage for guiding the polishing material M introduced from the introduction passage 35 to the injection port 49.

In one embodiment, the nozzle 48 may further have an inclined surface 48b connected to an upper end of the inner circumferential surface 48 a. The inclined surface 48b extends along a conical surface extending around the axis Z and having a diameter that becomes smaller as it approaches the nozzle tip side. That is, in the cross-sectional view shown in fig. 2, the inclined surface 48b is inclined so as to approach the axis Z as approaching the nozzle tip side. The inclined surface 48b functions to guide the polishing material M introduced into the buffer chamber 44s to the inlet side of the gap 74.

The end of the gap 74 on the nozzle tip side, that is, the outlet of the gap 74 constitutes the ejection port 49 that ejects the abrasive material M. Fig. 5 is a bottom view of the front end portion 33. As shown in fig. 5, the injection port 49 of the nozzle 20 is formed between the lower surface of the rod 47 and the lower surface of the head 48, and has an annular shape centered on the axis Z. The injection port 49 communicates with the introduction passage 35 via the gap 74, the buffer chamber 44s, and the diffusion chamber 38 s.

Next, the flow of the abrasive M in the nozzle 20 will be described with reference to fig. 6. The polishing material M taken out of the tank 52 is supplied as a solid-gas two-phase to the introduction pipe 34 through the supply pipe 22 by the quantitative supply mechanism 54. The polishing material M supplied to the introduction pipe 34 flows through the introduction passage 35 along the axis Z direction and is introduced into the diffusion chamber 38 s. Here, the introduction path 35 extends linearly in the direction of the axis Z and has a sufficient length L with respect to the opening width w of the through hole 36, so that the abrasive M is rectified to flow in a direction parallel to the direction of the axis Z while the abrasive M passes through the introduction path 35.

The polishing material M introduced into the diffusion chamber 38s along the axis Z direction is diffused in the diffusion chamber 38s by colliding with the diffusion plate 41 and rebounding. The diffused abrasive M randomly passes through any one of the plurality of openings 43 and is introduced into the buffer chamber 44 s. At this time, since the polishing material M is introduced into the diffusion chamber 38s in a rectified state, the amount of the polishing material M passing through each of the plurality of openings 43 is equalized.

The polishing material M introduced into the buffer chamber 44s collides with the inclined surface 48b and is guided to the gap 74 along the inclined surface 48 b. The guided abrasive M is introduced from the entrance of the gap 74 and flows in the gap 74. Thereby, the flow direction of the abrasive M changes to a direction along the side surface 47a of the rod 47, i.e., a direction inclined at an angle θ with respect to the axis Z. The polishing material M flowing through the gap 74 is ejected toward the object W from the annular ejection port 49 centered on the axis Z.

As shown in fig. 6, the direction of the abrasive M ejected from the ejection port 49 is along the extending direction of the side surface 47a of the rod 47. That is, the abrasive M is ejected from the ejection port 49 in a direction inclined to the radial side with respect to the axis Z with reference to the axis Z, that is, in a direction away from the axis Z as departing from the ejection port 49. The injection direction coaxial line Z in which the abrasive M is injected from the injection port 49 coincides with the angle θ formed by the side surface 47a of the rod 47. The abrasive M ejected from the ejection port 49 collides with the object W, and as a result, a space such as a hole or a groove is formed in the surface of the object W. Here, since the polishing material M collides with the side wall defining the space from the oblique direction, the tapered surface of the side wall can be removed, and as a result, the verticality of the space can be improved.

Fig. 7 is a cross-sectional view of the jet flow of the abrasive material M along line VII-VII of fig. 6. Since the injection port 49 has an annular shape, the flow of the polishing material M injected from the injection port 49 has an annular pattern in a cross-sectional view orthogonal to the axis Z, as shown in fig. 7. That is, the abrasive M is ejected from the ejection port 49 in the entire direction around the axis Z in a direction inclined to the radial side with respect to the axis Z with the axis Z as a reference, that is, in a direction away from the axis Z as it leaves the ejection port 49. By jetting the abrasive M in this way, a space can be formed isotropically in the object W to be processed.

Next, a shot peening method according to an embodiment will be described. Fig. 8 is a flowchart illustrating a shot peening method MT according to an embodiment. The method MT is performed using the shot peening apparatus 10 shown in fig. 1.

In the method MT, first, step ST11 is performed. In step ST11, a dry film is formed on the object W. A mask pattern corresponding to the shape of a space to be formed in the object W is formed on the dry film. Next, in step ST12, the polishing material M is introduced from the supply pipe 22 into the introduction pipe 34. The abrasive M introduced into the introduction pipe 34 is rectified to flow parallel to the axis Z direction while flowing through the introduction passage 35.

Next, in step ST13, the polishing material M passing through the introduction pipe 34 collides with the diffusion plate 41 and is diffused in the diffusion chamber 38 s. By diffusing the abrasive material M, the distribution uniformity of the abrasive material M in the circumferential direction of the ejection port 49 is thereby improved. Next, in step ST14, the diffused abrasive M is ejected from the ejection port 49 through the plurality of openings 43, the buffer chamber 44s, and the gap 74. Here, the abrasive M is ejected in a direction inclined to the radial side with respect to the axis Z with reference to the axis Z, that is, in a direction away from the axis Z as departing from the ejection port 49. The polishing material M ejected from the ejection port 49 collides with the object W, and as a result, a hole, a groove, or the like is formed in the surface of the object W.

The nozzle, the shot-peening apparatus, and the shot-peening method according to the various embodiments have been described above, but the present invention is not limited to the above embodiments, and various modifications can be made without departing from the scope of the invention.

For example, although the rod 47 has a truncated cone shape in the above embodiment, the rod 47 may have any shape as long as the rod 47 has the reverse-tapered side surface 47a that extends along the axis Z and that extends along a conical surface whose diameter increases as it approaches the ejection opening 49. For example, the rod 47 may have a three-dimensional shape partially including a truncated cone shape, or may have a conical shape.

In the above embodiment, the rod 47 and the shower head 48 may be made of any wear-resistant material other than boron carbide. The surfaces of the components of the upper and lower bodies 38, 40 may be coated with a wear-resistant material such as boron carbide.

The present invention will be described more specifically with reference to the following experimental examples, but the present invention is not limited to the following experimental examples.

In this experimental example, the object W was subjected to shot peening using the nozzle 20 shown in fig. 2. In this experimental example, first, a dry film F (NCM250) manufactured by Nikko-Materials was formed on the object W, and then, exposure development was performed to form a resist mask on the object W. A resist pattern having a hole pattern with a diameter of 60 μm was formed on the dry film F. As the object W to be processed, a glass epoxy substrate having a thickness of 40 μm was used.

In the present experimental example, three nozzles having different angles θ between the side surface 47a of the rod 47 and the axis Z were prepared. Specifically, in experimental example 1, a through hole was formed in the object W using a nozzle having an angle θ set to 5 °. Similarly, in experimental example 2 and experimental example 3, the through-hole was formed in the object W using the nozzles whose angles θ were set to 10 ° and 15 °, respectively. In experimental examples 1 to 3, the angle of the side wall of the through hole formed in the object W was measured.

In experimental examples 1 to 3, boron carbide was used as the material of the rod 47 and the shower head 48. In addition, the width of the gap 74 between the rod 47 and the head 48 is 1 mm. Other processing conditions of experimental examples 1 to 3 are as follows.

Abrasive material M: WA #1500 (white alumina abrasive manufactured by Songhe corporation)

Moving speed of the nozzle 20: 10m/min

Moving speed of the processing table 24: 20mm/min

Width of movement of the nozzle 20: 150mm

Distance between nozzle 20 and object to be treated W: 20mm

Injection pressure: 0.15MPa

Ejection amount of abrasive material M: about 80g/min

Fig. 9 is a cross-sectional view showing the shape of the hole formed in the object W according to experimental examples 1 to 3. As shown in fig. 9 (a), the through-hole formed in experimental example 1 had an opening width of 59 μm on the front surface side of the object W and an opening width of 28 μm on the back surface side of the object W. The side wall of the through hole was inclined at an angle of 19.8 ° with respect to the axial direction of the through hole. In experimental example 1, the through-hole was formed in the object W by scanning the object W three times.

As shown in fig. 9 (b), the through-hole formed in experimental example 2 had an opening width of 59 μm on the front surface side of the object W and an opening width of 38 μm on the back surface side of the object W. The side wall of the through hole was inclined at an angle of 13.8 ° with respect to the axial direction of the through hole. In experimental example 2, the through-hole was formed in the object W by scanning the object W twice.

As shown in fig. 9 (c), the through-hole formed in experimental example 3 had an opening width of 59 μm on the front surface side of the object W and an opening width of 50.8 μm on the back surface side of the object W. The side wall of the through hole was inclined at an angle of 4.4 ° with respect to the axial direction of the through hole. In experimental example 3, the through-hole was formed in the object W by scanning the object W twice.

From experimental examples 1 to 3, it was confirmed that: by changing the angle θ formed by the side surface 47a of the lever 47 and the axis Z, the angle of the side wall defining the space can be adjusted. In addition, in experimental example 1, the through-hole was formed by scanning the object W three times, and in experimental example 2 and experimental example 3, the through-hole was formed by scanning the object W two times. From the results, it was confirmed that: by changing the angle θ, the efficiency of the drilling process also changes.