Nozzle body

Abstract

The present invention provides a nozzle body for injecting slurry, wherein processing is uniform in an opening direction even when processing is performed with an injection port directed in any direction. This nozzle body includes: a slurry storage chamber in which slurry in which abrasive grains and liquid are mixed is introduced and temporarily stored; an air storage chamber into which pressurized air is introduced and temporarily stored; and a passageway which communicates with the slurry storage chamber and the air storage chamber and injects from an injection port an injection material in which the slurry and the pressurized air are mixed. The slurry storage chamber includes a slurry introduction port for introducing the slurry. The slurry introduction port includes a turning means for swirling the slurry.

Description

Nozzle body

[0001] The present invention relates to a nozzle body for spraying abrasives against a workpiece or the like, and more particularly to a nozzle body for wet blasting that uses abrasives that are a mixture of slurry and air.

[0002] Conventionally, wet blasting, also known as wet blasting or liquid honing, involves preparing a slurry made by mixing liquid and abrasive grains, and spraying this slurry onto the workpiece using compressed air to treat the surface of the workpiece.

[0003] Here, in wet blasting, it is sometimes important to collide the slurry uniformly and with high power against the workpiece, etc. For example, in the case of performing peening, which changes the mechanical properties of the workpiece by colliding shots (abrasive grains, etc.) contained in the slurry against the surface of the workpiece, it is required that the shots have high collision energy and can collide uniformly with the surface of the workpiece.

[0004] Nozzle bodies that can spray wet blasting uniformly and with high power over a wide area are known, such as those described in Patent Documents 1 and 2.

[0005] The nozzle body described in Patent Document 1 has an air injection passage provided near a slurry storage chamber where a slurry of abrasive grains and liquid is introduced and temporarily stored, and pressurized air passes through this air injection passage, causing the slurry to be discharged from the slurry storage chamber via an outlet passage having a predetermined length, and the slurry and the pressurized air are sent to a mixing chamber where they are mixed, and the aerosol material formed by mixing the pressurized air and the slurry is sprayed from a slit-shaped injection portion, and the outlet passage has a porous structure with small holes arranged in the longitudinal direction of the outlet passage.

[0006] Furthermore, the nozzle body described in Patent Document 2 is provided with a slurry storage chamber into which a slurry of a mixture of granular material and liquid is introduced and temporarily stored, and also with an air storage chamber into which pressurized air is introduced and temporarily stored, and an air injection passage is connected to this air storage chamber, and the pressurized air stored in the air storage chamber is introduced from the air injection passage into a mixing chamber, whereby the slurry is led from the slurry storage chamber to the mixing chamber and the slurry and the pressurized air are mixed, and the nozzle body injects the abrasive material, which is a mixture of the pressurized air and the slurry, from a slit-shaped injection port onto a workpiece, and the slit-shaped injection port has an opening shape that is short in the length direction of the workpiece and long in the width direction, and between the mixing chamber and the slit-shaped injection port, a passageway through which the aerosol can travel in a straight line is provided, and the positional relationship between the air injection passageway, the passageway, and the slit-shaped injection port is set to be linear; the air injection passageway has a porous structure with small holes arranged side by side; the cross-sectional area of ​​the air injection passageway in a direction perpendicular to the pressurized air passageway is the sum of the cross-sectional areas of the small holes in a direction perpendicular to the pressurized air passageway; the ratio of the opening area of ​​the slit-shaped injection port to the cross-sectional area of ​​the air injection passageway in the direction perpendicular to the pressurized air passageway is set to 2.0 to 1.0:1.0; and further, the ratio of the cross-sectional area of ​​the air injection passageway to the cross-sectional area of ​​the pressurized air in the air storage chamber in the direction perpendicular to the pressurized air passageway is set to 1.0:3.0 or more.

[0007] The nozzle body described in Patent Document 1 has a porous structure in which the outlet passage has small holes arranged in the longitudinal direction of the outlet passage, so that abrasive grains, liquid, and pressurized air can be sprayed in a uniform mixture even from a very long slit-shaped injection port.

[0008] The nozzle body described in Patent Document 2 can spray wet blast uniformly and with high power even when the pressure of the pressurized air is increased in the peening process by appropriately setting the ratio between the opening area of ​​the slit-shaped injection port, the passage cross-sectional area of ​​the air injection passage, and the passage cross-sectional area in the direction perpendicular to the direction in which the pressurized air passes in the air storage chamber.

[0009] Patent No. 3540713 Patent No. 4210076

[0010] However, with conventional nozzle bodies, when processing a workpiece with the slit-shaped injection nozzle facing downward, or when processing a workpiece with the slit-shaped injection nozzle facing horizontally and positioned so that the opening direction of the slit-shaped injection nozzle is vertical, as shown in Figure 8, there is a problem in that a difference in slurry concentration occurs in the opening direction of the slit-shaped injection nozzle, and this difference in concentration impairs the uniformity of processing in the opening direction.

[0011] As shown in FIG. 8, this issue can be confirmed by the fact that when the slurry concentration is low (e.g., 7.5 Vol%), the difference in processing time in the opening direction (measurement position) is greater than when the slurry concentration is high (e.g., 27.5 Vol%).

[0012] The present invention has been made to solve the above-mentioned problems, and aims to provide a nozzle body that sprays slurry and that ensures uniform processing in the opening direction regardless of the direction in which the spray nozzle is pointed during processing.

[0013] The nozzle body of the present invention, which solves the above problems, comprises a slurry storage chamber into which a slurry mixture of abrasive grains and liquid is introduced and temporarily stored, an air storage chamber into which pressurized air is introduced and temporarily stored, and a passageway which communicates with the slurry storage chamber and the air storage chamber and through which an abrasive material mixture of the slurry and the pressurized air is sprayed from an injection port, wherein the slurry storage chamber is provided with a slurry inlet for introducing the slurry, and the slurry inlet is provided with a swirling means for swirling the slurry.

[0014] Furthermore, in the nozzle body according to the present invention, it is preferable that the rotating means comprises an inlet portion that introduces the slurry from a direction intersecting the inlet direction of the pressurized air, and an outlet portion that discharges the slurry in the slurry storage chamber in a direction approximately parallel to the inlet direction of the pressurized air.

[0015] In the nozzle body according to the present invention, it is preferable that the swirling means comprises a swirling portion main body that connects the inlet portion and the outlet portion.

[0016] In the nozzle body according to the present invention, it is preferable that the swirl portion main body is disposed approximately concentrically with the outlet portion, and the introduction portion extends in a tangential direction of the swirl portion main body.

[0017] In the nozzle body according to the present invention, it is preferable that the injection port has a slit shape extending along the width direction of the workpiece.

[0018] Furthermore, in the nozzle body according to the present invention, it is preferable that the slurry storage chamber has a slurry storage chamber opening at its lower end along the direction in which the pressurized air is introduced, which is connected to the injection port and opens in the form of a slit along the width direction, and that the inner wall of the slurry storage chamber has a flow path adjustment means whose height along the direction in which the pressurized air is introduced and whose width along the width direction do not overlap with the slurry storage chamber opening.

[0019] In the nozzle body according to the present invention, it is preferable that the flow path adjusting means is a spacer member that is detachably attached to the slurry storage chamber.

[0020] In addition, in the nozzle body according to the present invention, it is preferable that the spacer member is attached to both ends of the slurry storage chamber in the width direction, and comprises a base attached to the side wall of the slurry storage chamber, and an extension extending from the base along the width direction.

[0021] In addition, in the nozzle body according to the present invention, it is preferable that the tip of the extension portion is formed so as not to overlap with the slurry inlet port and has a slope inclined with respect to the introduction direction of the slurry introduced from the slurry inlet port.

[0022] Furthermore, a wet shot peening method according to the present invention is characterized in that the slurry is projected onto the surface of a workpiece using the nozzle body.

[0023] According to the nozzle body of the present invention, the inlet for introducing the slurry is provided with a swirling means for swirling the slurry, so that the slurry is stirred by swirling within the slurry storage chamber, and the concentration of the slurry within the slurry storage chamber becomes uniform.Even if the nozzle body is positioned so that the slurry is projected horizontally, for example, the concentration of the slurry can be made uniform at any position of the injection port, making it possible to prevent a decrease in processing quality.

[0024] 1 is a perspective view of a wet blasting processing apparatus using a nozzle body according to a first embodiment of the present invention. An exploded perspective view of a nozzle body according to the first embodiment of the present invention. An A-A cross-sectional view in FIG. 1. A B-B cross-sectional view in FIG. 3. A C-C cross-sectional view in FIG. 4. A cross-sectional view corresponding to FIG. 3 of a nozzle body according to a second embodiment of the present invention. A D-D cross-sectional view in FIG. 6. A graph showing the processing time until area coverage is 100% at each measurement position in the slit width direction of a nozzle body according to the first embodiment of the present invention. A graph showing the processing time characteristics of intensity of a nozzle body according to the first embodiment of the present invention. A graph showing the processing time until area coverage is 100% at each measurement position in the slit width direction of a nozzle body according to a second embodiment of the present invention. A graph showing the processing time characteristics of intensity of a nozzle body according to the second embodiment of the present invention. A graph showing the processing time until area coverage is 100% at each measurement position in the slit width direction of a conventional nozzle body.

[0025] Preferred embodiments for carrying out the present invention will be described below with reference to the drawings. Note that the following embodiments do not limit the inventions according to the claims, and not all of the combinations of features described in the embodiments are necessarily essential to the solution of the invention.

[0026] [First embodiment] Fig. 1 is a perspective view of a wet blasting processing apparatus using a nozzle body according to a first embodiment of the present invention, Fig. 2 is an exploded perspective view of the nozzle body according to the first embodiment of the present invention, Fig. 3 is a cross-sectional view taken along line A-A in Fig. 1, Fig. 4 is a cross-sectional view taken along line B-B in Fig. 3, and Fig. 5 is a cross-sectional view taken along line C-C in Fig. 4.

[0027] 1 , a nozzle body 10 according to this embodiment is suitable for use in a wet blasting treatment apparatus 1. The wet blasting treatment apparatus 1 sprays abrasives 5 onto the surface of a workpiece W held by a holder 2, thereby performing surface treatment on the workpiece W. The nozzle body 10 sprays the abrasives 5 in a band shape from a slit-shaped spray nozzle 11 extending in the width direction of the workpiece W.

[0028] The wet blasting apparatus 1 to which the nozzle body 10 according to this embodiment is applied can be used to perform various conventionally known processes, but is preferably used for wet shot peening, for example.

[0029] It is preferable to use a slurry, which is a mixture of liquid and abrasive grains, as the abrasive material 5. The liquid contained in the slurry serves to carry the abrasive grains, which will be described later, to the surface of the workpiece. Therefore, any liquid can be used as long as it can fulfill this role, except for flammable substances. Specifically, it is preferable to use water from the viewpoints of environmental considerations and cost.

[0030] The abrasive grains are carried to the surface of the workpiece by the liquid and serve to perform the desired processing on the surface of the workpiece, so any abrasive grains can be used as long as they can perform this function.

[0031] Specifically, examples of the abrasive material include ceramics, resin, and metal, and more specifically, examples of the abrasive material include alumina, glass, zirconia, and stainless steel. Examples of the shape of the abrasive include polygonal, spherical, and true spherical shapes. The size of the abrasive can be appropriately selected from approximately 1 μm to 300 μm. In the nozzle body 10 according to this embodiment, it is preferable to use abrasive grains with a high specific gravity (e.g., 6 or more), and abrasive grains with a diameter of, for example, approximately 250 μm.

[0032] Furthermore, in order to impart higher compressive residual stress to a workpiece with high hardness (a workpiece having high hardness), it is necessary to increase the impact energy when the shot material contained in the slurry is impacted on the workpiece. However, as the hardness of the workpiece increases, energy loss is likely to occur in the impact energy when the shot material contained in the slurry is impacted on the workpiece, and this energy loss can cause problems such as insufficient compressive residual stress being imparted to the workpiece. Furthermore, if the projection pressure (spray pressure) of the slurry is increased in order to increase the impact energy, problems such as the shot material being crushed can occur.

[0033] Therefore, in the wet shot peening method in such a case, yttria-stabilized zirconia is used as the shot material. In other words, in the wet shot peening method using the nozzle body 10 according to the present embodiment, a slurry in which a liquid and yttria-stabilized zirconia are mixed is used. In this specification, yttria-stabilized zirconia means zirconia whose crystal structure is stabilized by yttria.

[0034] The proportion of abrasive grains in the entire slurry is not particularly limited and can be appropriately designed depending on the material and processing area of ​​the workpiece, as well as the desired degree of processing. For example, a high concentration of 30 vol% (72 wt%) or more of the total volume of the slurry is preferable. In this case, stress can be applied to the workpiece W more effectively and efficiently.

[0035] In addition to the liquid and abrasive grains, the slurry may contain additives with various functions, such as a rust inhibitor. By including a rust inhibitor in the slurry used in the wet blasting method, it is possible to impart rust prevention effects to the surface of the workpiece while simultaneously subjecting it to conventional wet blasting. Instead of the rust inhibitor, various additives may be added to the slurry to the extent that they do not impair the effects of the other components.

[0036] As shown in Figure 2, the nozzle body 10 is composed of an elongated member 20 that is long in the width direction of the workpiece W (left and right direction, a direction perpendicular to the direction of movement when processing is performed) and short in the front and rear direction (the direction of movement when processing is performed), an elongated, thin-walled plate-like member 30 that is connected in a vertical state to the bottom of the elongated member 20 and is long in the width direction and has a slit-shaped injection port 11 at its bottom end, and a block-shaped fitted member 40 that is connected to the top of the elongated member 20 in a fitted state.

[0037] 3, a plurality of hole-like through-passages 21 are formed at predetermined intervals inside the elongated member 20. The through-passages 21 are preferably formed to have a diameter of, for example, about φ2.5, and an air injection passage 43 is formed in the front body 41 (described later) at the top of the through-passages 21 and is provided adjacent thereto for introducing pressurized air into the through-passages 21.

[0038] Furthermore, on the side of the elongated member 20 (the side facing the rear body 42, which will be described later), a merging path 22 is formed at an angle to the vertical direction at the upper end of the passage path 31 formed in the plate-like member 30. The inclination angle of the merging path 22 is preferably formed at 30° to 60°, and more preferably at about 45°. Unlike the through path 21, the merging path 22 is preferably formed as a slit that is long in the width direction. Furthermore, a pair of engagement portions 23 are formed below the elongated member 20, extending downward from the side.

[0039] The plate-like member 30 is provided with a passage 31 that communicates with the slit-shaped injection port 11 formed at the lower end and through which the abrasives 5 can travel in a straight line. In addition, a protrusion 32 is formed at the upper end of the plate-like member 30 to engage with a pair of engaging portions 23, 23 formed on the elongated member 20. Furthermore, a pair of engaging protrusions 33 are formed on the sides of the plate-like member 30.

[0040] The positional relationship between the opening of the air injection passage 43, the through path 21, the passage path 31 and the slit-shaped injection port 11 is set to be linear.

[0041] The fitted member 40 is formed of a front body 41 and a rear body 42, and sandwiches the elongated member 20 and the plate-like member 30 in a direction perpendicular to the width direction. In addition, the front body 41 and the rear body 42 of the fitted member 40 are each formed with protrusions 44, 44 that engage with the engaging protrusions 33 formed on the plate-like member 30.

[0042] The front body 41 is formed with an air storage chamber 45 into which pressurized air is introduced and temporarily stored, an air inlet 46 that introduces pressurized air into the air storage chamber 45, and an air injection passage 43 that communicates with the air storage chamber 45.

[0043] As shown in Fig. 2, the air storage chamber 45 is formed to extend in the width direction of the front body 41, and the air inlet 46 is formed singly in the approximate center of the front body 41. As shown in Fig. 4, lid bodies 12 are attached to both ends of the fitted member 40 in the width direction via seal members 13, and the air storage chamber 45 is closed in the width direction by the lid bodies 12.

[0044] The base end of the air injection passage 43 is formed as a through passage that penetrates from the side wall of the air storage chamber 45 on the rear body 42 side toward the rear body 42, and more preferably, the air injection passage 43 extends in a tangential direction from the upper end of the air storage chamber 45. The tip end of the air injection passage 43 communicates with the through passage 21 of the elongated member 20 when combined with the rear body 42.

[0045] The rear body 42 is formed with a slurry storage chamber 47 into which the slurry is introduced and temporarily stored, a slurry inlet 48 through which the slurry is introduced into the slurry storage chamber 47, and a slurry storage chamber opening 49 which communicates with the slurry storage chamber 47. In addition, a swiveling means 60, which will be described later, is attached to the slurry inlet 48.

[0046] 2, the slurry storage chamber 47 is formed to extend in the width direction of the rear body 42, and the slurry inlet 48 is formed singly in the approximate center of the rear body 42. As shown in FIG. 4, the lids 12 are attached to both ends of the fitted member 40 in the width direction via the sealing members 13, and the lids 12 close the slurry storage chamber 47 in the width direction.

[0047] Furthermore, the base end side of slurry reservoir chamber opening 49 is formed as a through passage that penetrates from the side wall of slurry reservoir chamber 47 on the front body 41 side toward front body 41. Furthermore, slurry reservoir chamber opening 49 is formed to extend tangentially from the lower end of slurry reservoir chamber 47, and its tip side communicates with joining path 22 of elongated member 20. In nozzle body 10 according to this embodiment, slurry reservoir chamber opening 49 and joining path 22 form a slurry joining path 50.

[0048] Furthermore, among the above components, a protective layer made of urethane rubber or the like is formed on the path through which the slurry passes (the inner wall of the slurry storage chamber 47, the inner wall of the slurry storage chamber opening 49, etc.) This protective layer prevents the path through which the slurry passes from being abraded by the slurry (particularly granular matter), and it has been confirmed that the existence of this protective layer extends the life of the nozzle body 10 several times.

[0049] As shown in FIG. 4, the slurry storage chamber opening 49 is formed as a slit that is long in the width direction, and spacer members 51 are attached to both ends of the width direction of the slurry storage chamber 47 to prevent the slurry introduced from the slurry inlet 48 from stagnating in the slurry storage chamber 47.

[0050] As shown in Figures 3 to 5, the swirling means 60 comprises a swirling section main body 60a, a connection section 61 extending from the swirling section main body 60a toward the slurry inlet 48 and having an outlet section 64 formed therein, a swirling section 62 formed in the swirling section main body 60a, and an inlet section 63 continuous with the swirling section 62.

[0051] The swivel unit main body 60a is a block-shaped member having a swivel unit 62 that has a circular cross section and penetrates vertically. The swivel unit 62 has an annular portion 62a that extends substantially vertically from above the swivel unit main body 60a, and an inclined tapered portion 62b that connects the lower end of the annular portion 62a to the outlet portion 64. As shown in Figure 5, the swivel unit 62 and the outlet portion 64 are arranged substantially concentrically.

[0052] As shown in Fig. 4, an inlet 63 is attached to the side of the swirl unit main body 60a, and a hose or the like for supplying slurry is attached to the inlet 63. The inlet 63 is formed on the side of the swirl unit main body 60a so as to be approximately perpendicular to the annular portion 62a of the swirl unit 62. As shown in Fig. 5, the inlet 63 is attached so as to extend in a tangential direction of the swirl unit 62. In this way, the inlet 63 intersects in a direction approximately perpendicular to the opening direction of the slurry inlet 48 that introduces the slurry into the nozzle body, and the outlet 64 is disposed in a direction approximately parallel to the opening direction of the slurry inlet 48.

[0053] In the nozzle body 10 configured in this manner, the slurry introduced into the slurry storage chamber 47 is rotated by the rotating means 60 and stirred within the slurry storage chamber 47, so that the concentration in the slurry storage chamber 47 becomes uniform, and it becomes possible to suppress a decrease in processing quality no matter in which direction the nozzle body 10 is used to spray the slurry, for example, in a horizontal direction.

[0054] Furthermore, the nozzle body 10 according to this embodiment is arranged so that the inlet portion 63 extends in the tangential direction of the swirling portion 62 of the swirling means 60, and therefore the slurry introduced from the inlet portion 63 is swirled along the inner wall of the swirling portion 62 while being discharged to the discharge portion 64, thereby imparting a reliable swirling motion to the slurry.

[0055] Furthermore, in the nozzle body 10 according to this embodiment, the slurry introduced into the swirling portion 62 is led out to the lead-out portion 64 via the tapered portion 62b, so that the swirling force imparted to the slurry introduced from the tangential direction of the annular portion 62a is not attenuated.

[0056] [Second Embodiment] In the nozzle body 10 according to the first embodiment described above, an embodiment in which spacer members 51 are attached to both widthwise ends of the slurry storage chamber 47 has been described. The nozzle body 10a according to the second embodiment described next will be described as an example of a slurry storage chamber 47 having a different configuration from that of the first embodiment. Note that components that are the same as or similar to those in the first embodiment described above will be assigned the same reference numerals and will not be described again.

[0057] FIG. 6 is a cross-sectional view of a nozzle body according to a second embodiment of the present invention, corresponding to FIG. 3, and FIG. 7 is a cross-sectional view taken along line DD in FIG.

[0058] As shown in Fig. 6, nozzle body 10a according to this embodiment has a flow path adjusting means (spacer member 70) attached along the inner wall of slurry storage chamber 47. As shown in Fig. 7, spacer member 70 extends in the width direction along the inner wall surface of slurry storage chamber 47 on the side of slurry inlet 48 (upper part of slurry storage chamber 47).

[0059] The spacer member 70 is composed of a pair of spacer member pieces 71, 71 that extend in opposing directions from both end faces of the slurry storage chamber 47 toward the center. The spacer member pieces 71 are preferably fastened together with the cover body 12 and the seal member 13 of the nozzle body 10a, and the spacer member pieces 71 arranged on the left and right in FIG. 7 preferably have the same shape.

[0060] Spacer piece 71 has a base 71a attached to the side wall of slurry storage chamber 47, and an extension 71b extending from base 71a in the width direction of slurry storage chamber 47. The tips of extensions 71b are positioned so that they do not block the opening of slurry inlet 48, and a slope 72 is formed at the end vertically opposite slurry inlet 48, forming a flow path continuing from slurry inlet 48 in a diverging shape.

[0061] 6 and 7, spacer member pieces 71 extend along the width direction of slurry storage chamber 47 but are configured not to block slurry storage chamber opening 49. This prevents the slurry introduced from slurry inlet 48 from stagnating in slurry storage chamber 47, thereby suppressing a decrease in the flow rate of the slurry. Furthermore, by suppressing a decrease in the flow rate of the slurry, it is possible to improve the uniformity in the width direction of nozzle body 10a even when nozzle body 10a according to this embodiment is arranged horizontally and the slurry is projected horizontally.

[0062] [Examples] Next, the present invention will be described in more detail with reference to examples. Fig. 8 is a graph showing the processing time until area coverage reaches 100% at each measurement position in the slit width direction of a nozzle body according to a first embodiment of the present invention, Fig. 9 is a graph showing the processing time characteristics of intensity of a nozzle body according to the first embodiment of the present invention, Fig. 10 is a graph showing the processing time until area coverage reaches 100% at each measurement position in the slit width direction of a nozzle body according to a second embodiment of the present invention, and Fig. 11 is a graph showing the processing time characteristics of intensity of a nozzle body according to the second embodiment of the present invention.

[0063] First, the nozzle body 10 according to the first embodiment was positioned horizontally, and slurries with concentrations of 9.1 Vol% and 22.9 Vol% were sprayed using a shot material with a specific gravity of 6. The processing time until area coverage, which is the percentage of impact marks at a position in the slit width direction of the slit-shaped nozzle, reached 100%, was measured. The test conditions were as follows: air pressure: 0.40 MPa, slurry pressure: 0.24 MPa. The nozzle body 10 was positioned horizontally and had a width of 60 mm, and the measurement position was set with the -24 mm side downward and the +24 mm side upward to spray the slurry. Measurement positions were set at five points spaced 12 mm apart from the opening end of the nozzle.

[0064] In Figure 8, the reason for using the processing time until area coverage reaches 100% is as follows: The "processing quality / strength" in blasting is determined by the "energy of the blast material (speed x mass)" x "number of blast material particles (concentration)." Here, if the particle diameter and specific gravity of the blast material are uniform, the "mass" will be constant.

[0065] Furthermore, the "speed" depends on the pressure and flow rate of the compressed air. In conventional air flow path structures such as those described in Patent Documents 1 and 2, the pressure and flow rate are constant across the nozzle width, and this structure is also applied to the nozzle body according to this embodiment.

[0066] With conventional nozzle body structures, "concentration," i.e., the amount of projection material in the slurry, is easily affected by gravity, particularly when projecting in the horizontal direction, resulting in differences in concentration across the nozzle width. The nozzle body of this embodiment reduces and suppresses concentration differences caused by gravity in the slurry flow path.

[0067] As mentioned above, "processing time" is the time (projection time) required to obtain a desired processing state / quality (in this case, "100% area coverage"), and is "the time until the same (constant) number of projection material particles with equal (constant) speeds collide with the surface of the workpiece."

[0068] In the nozzle body of this embodiment, the "speed" is constant (uniform) across the width of the nozzle, so the "processing time" can be replaced with the "projection material concentration." In principle, the best way to indicate uniformity in the nozzle width direction is to indicate the concentration in the nozzle width direction, but it is difficult to measure local concentrations in the nozzle width direction. Therefore, in Figure 8, the "processing time until area coverage reaches 100%" is used as a value indicating the processing quality / strength.

[0069] As shown in Figure 8, when the nozzle body 10 of this embodiment is projected horizontally, it can be confirmed that the processing time is uniform regardless of the measurement position, and it can be confirmed that the processing variation in the opening direction of the injection port is reduced compared to the conventional nozzle body shown in Figure 12.

[0070] Furthermore, as shown in Figure 9, it was confirmed that the arc height, which is the height at which the machined surface is hammered and extended, is uniform regardless of the measurement position when measuring the intensity processing time characteristics. The measurement of the intensity processing time characteristics was carried out using a blast material (TZ-B250) with a specific gravity of 6, and the concentration was set to 23.0 Vol%. The spray direction and measurement position of the nozzle body 10 were the same as those used to measure the area coverage described above.

[0071] It has been confirmed that the nozzle body 10 of this embodiment, configured in this manner, does not degrade the processing quality even when the nozzle body 10 is positioned horizontally and the slurry is sprayed in a direction other than vertically downward toward the workpiece.

[0072] The nozzle body 10 according to this embodiment is capable of uniformly treating a wide surface, and is therefore suitable for use, for example, in pre-treatment for transparent roughening by projecting slurry onto a glass surface.

[0073] Next, the nozzle body 10a according to the second embodiment was positioned horizontally, and a slurry with a concentration of 5.7 Vol% was sprayed using a shot material with a specific gravity of 6. The processing time until area coverage, which is the percentage of impact marks at a position in the slit width direction of the slit-shaped spray nozzle, reached 100%, was measured. The test conditions were as follows: air pressure: 0.40 MPa, slurry pressure: 0.24 MPa. The horizontally positioned nozzle body 10a was set wider than the nozzle body 10 according to the first embodiment, specifically, a width of 100 mm. The measurement position was set with the -44 mm side downward and the +44 mm side upward, and the slurry was sprayed. Measurement positions were set at five points spaced 22 mm apart from the opening end of the spray nozzle.

[0074] As shown in Figure 10, when the nozzle body 10a according to this embodiment was projected in the horizontal direction, it was confirmed that the processing time was uniform regardless of the measurement position, and that the variation in processing in the direction of the nozzle opening was reduced compared to the conventional nozzle body shown in Figure 12. Furthermore, with the nozzle body 10 according to the first embodiment, uniformity sometimes became unstable when the concentration of the projection material was reduced, but with the nozzle body 10a according to this embodiment, it was confirmed that sufficient performance was maintained in terms of uniformity even when the nozzle width was wider or the concentration of the projection material was reduced.

[0075] Furthermore, as shown in Figure 11, it was confirmed that the arc height, which is the height at which the machined surface is hammered and extended, is uniform regardless of the measurement position when measuring the intensity processing time characteristics. The measurement of the intensity processing time characteristics was carried out using a blast material (TZ-B250) with a specific gravity of 6, and the concentration was set to 5.7 Vol%. The spray direction and measurement position of the nozzle body 10a were the same as those used to measure the area coverage described above.

[0076] It has been confirmed that the nozzle body 10 according to the first embodiment and the nozzle body 10a according to the second embodiment configured in this manner do not degrade the processing quality even when the nozzle bodies 10, 10a are arranged horizontally and the slurry is sprayed in a direction other than vertically downward onto the workpiece.

[0077] Furthermore, while the nozzle bodies 10 and 10a according to the first and second embodiments have been described as having slit-shaped injection ports, the shape of the injection port is not limited to slits and various injection port shapes may be used. Furthermore, while the embodiment has been described as having one air inlet 46 and one slurry inlet 48 formed in the fitted member 40, the number of air inlets 46 and one slurry inlet 48 is not limited to this and may be increased as appropriate. In this case, the number of swirling means 60 may be increased in accordance with the number of slurry inlets 48.

[0078] Furthermore, in the nozzle body 10a according to the second embodiment, the spacer member 70 has been described as being attached to the slurry storage chamber 47, but the flow path adjusting means may be formed integrally with the rear body 42 by reducing the volume of the slurry storage chamber 47 and forming the slurry storage chamber 47 in substantially the same shape as when the spacer member 70 is attached. Furthermore, in the nozzle body 10a according to the second embodiment, the slurry is directly introduced into the slurry inlet 48, but as in the nozzle body 10 according to the first embodiment, the swirling means 60 may be attached to the slurry inlet 48. It is clear from the claims that such modified or improved forms are also included within the technical scope of the present invention.

[0079] REFERENCE SIGNS LIST 1 Wet blasting treatment apparatus, 2 Holding section, 5 Abrasive material, 10 Nozzle body, 11 Slit-shaped injection port, 12 Lid body, 20 Long member, 21 Through path, 22 Merging path, 23 Engaging section, 30 Plate-shaped member, 31 Passing path, 32 Convex section, 33 Engaging convex section, 40 Fitted member, 41 Front body, 42 Rear body, 43 Air injection passage, 44 Protrusion, 45 Air storage chamber, 46 Air inlet, 47 Slurry storage chamber, 48 Slurry inlet, 49 Slurry storage chamber opening, 50 Slurry merging path, 51, 70 Spacer member, 60 Swiveling means, 60a Swiveling section main body, 61 Connection section, 62 Swiveling section, 62a Annular portion, 62b tapered portion, 63 introduction portion, 64 extraction portion, 71 spacer member piece, 71a base portion, 71b extension portion, 72 inclined surface W workpiece.

Claims

1. A nozzle body having a slurry storage chamber into which a slurry, which is a mixture of abrasive grains and liquid, is introduced and temporarily stored, an air storage chamber into which pressurized air is introduced and temporarily stored, and a passageway that communicates with the slurry storage chamber and the air storage chamber and through which an abrasive material, which is a mixture of the slurry and the pressurized air, is sprayed from an injection port, wherein the slurry storage chamber is provided with a slurry inlet port through which the slurry is introduced, and the slurry inlet port is provided with a swirling means for swirling the slurry.

2. A nozzle body as described in claim 1, characterized in that the rotating means comprises an inlet portion for introducing the slurry from a direction intersecting the inlet direction of the pressurized air, and an outlet portion for discharging the slurry in the slurry storage chamber in a direction approximately parallel to the inlet direction of the pressurized air.

3. A nozzle body as claimed in claim 2, characterized in that the swirling means comprises a swirling body connecting the inlet section and the outlet section.

4. A nozzle body as described in claim 3, characterized in that the swirl portion main body is arranged approximately concentrically with the outlet portion, and the inlet portion extends in a tangential direction of the swirl portion main body.

5. A nozzle body as claimed in claim 1, characterized in that the injection port is in the form of a slit extending along the width direction of the workpiece.

6. A nozzle body as described in claim 5, wherein the slurry storage chamber has a slurry storage chamber opening at its lower end along the introduction direction of the pressurized air, which opens in the form of a slit along the width direction and communicates with the injection port, and the inner wall of the slurry storage chamber is provided with a flow path adjustment means whose height along the introduction direction of the pressurized air and whose width along the width direction do not overlap with the slurry storage chamber opening.

7. A nozzle body as set forth in claim 6, wherein said flow path adjusting means is a spacer member detachably attached to said slurry storage chamber.

8. A nozzle body as described in claim 7, wherein the spacer members are attached to both ends of the slurry storage chamber in the width direction, and each have a base attached to a side wall of the slurry storage chamber, and an extension extending from the base along the width direction.

9. A nozzle body as described in claim 8, characterized in that the tip of the extension portion is formed so as not to overlap with the slurry inlet port and has a slope inclined with respect to the introduction direction of the slurry introduced from the slurry inlet port.

10. A wet shot peening method comprising projecting said slurry onto a surface of a workpiece using a nozzle body as defined in any one of claims 1 to 9.

Images