Blast gun

Abstract

To provide a blast gun 1 comprising a curved pipe part 12 for switching a blast medium travel direction in which uneven wear of a circulation part of a blast medium BM can be suppressed.SOLUTION: A blast gun comprises: a first straight pipe part 10 including a medium flow channel 20 for circulating a blast medium and an air flow channel 21 for circulating compressed air CA; a second straight pipe part 11 including an injection flow channel 22 which circulates the blast medium sent out from the first straight pipe part and guides the same to an injection port 32; and a curved pipe part including a curved flow channel 24 which connects the first straight pipe part and the second straight pipe part. The air flow channel is separated from the medium flow channel at least from the curved flow channel. In the second straight pipe part, a suction region 40, in which a downstream side tip of the air flow channel and a downstream side tip of the medium flow channel communicate with the injection flow channel and the blast medium is sucked by compressed air and is sent out to the injection port, is formed.SELECTED DRAWING: Figure 2

Description

[Technical field]

[0001] The present disclosure relates to a blast gun. [Background technology]

[0002] Conventionally, there is a blasting device that performs blasting on a workpiece. The blasting device includes a blasting gun that uses compressed air to spray blasting media such as abrasive grains onto the workpiece. As a blasting gun that can be used in the blasting device, Patent Document 1 describes a blasting nozzle that includes a curved pipe section that switches the traveling direction of the blasting media in a blasting media air delivery pipe, which is a pipe that delivers the blasting media by carrying it on an air current.

[0003] With this blast nozzle configuration, the collision flow velocity of the blast media to the fastest wear area connected to the nozzle side of the curved pipe section is reduced, which is said to extend the life of the parts on the nozzle side of the blast nozzle described in Patent Document 1. [Prior art documents] [Patent documents]

[0004] [Patent Document 1] JP 2017-52029 A Summary of the Invention [Problem to be solved by the invention]

[0005] However, although such a blast nozzle reduces uneven wear by lowering the collision flow speed of the blast media in the nozzle area, there is still room for further improvement in reducing uneven wear caused by the blast media being carried by the airflow.

[0006] Therefore, an object of the present disclosure is to provide a blast gun for a blasting device having a curved pipe section that switches the direction in which the blasting media travels, which can more effectively suppress uneven wear in the portion through which the blasting media flows. [Means for solving the problem]

[0007] A blast gun according to one embodiment of the present disclosure is a blast gun that uses compressed air to spray blast media. The blast gun includes a first straight pipe section, a second straight pipe section, and a curved pipe section. The first straight pipe section includes a media flow path through which the blast media flows, and an air flow path disposed within the media flow path through which the compressed air flows. The second straight pipe section includes an injection flow path through which the blast media sent out from the first straight pipe section flows and leads it to an injection port. The curved pipe section includes a curved flow path that connects the first straight pipe section and the second straight pipe section, and is an area where the media flow path and the air flow path are curved so that the extension direction of the first straight pipe section and the extension direction of the second straight pipe section are different directions. The air flow path is separated from the inner circumferential surface of the media flow path at least from the curved flow path. Within the second straight pipe section, a suction area is provided in which the downstream end of the air flow path and the downstream end of the media flow path are connected to the injection flow path, and the blast medium is sucked in by the compressed air and delivered to the injection port.

[0008] In the above blast gun, the downstream end of the air flow path may be arranged coaxially with the media flow path in the second straight pipe section. The media flow path and the air flow path may extend in parallel with each other along the extension direction of the first straight pipe section in at least a part of the first straight pipe section. The first straight pipe section may have an air inlet for introducing compressed air from the outside to the upstream side of the air flow path, and a media inlet for introducing blast media from the outside to the upstream side of the media flow path, the media inlet being provided in a side wall of the first straight pipe section, and the air inlet being provided in an end of the first straight pipe section opposite to the side connected to the curved pipe section. An air nozzle continuous with the air flow path and a media circulation space continuous with the media flow path may be arranged in the suction area, and a tip opening of the air nozzle may project into the curved flow path so that an outer peripheral area of ​​the tip opening becomes the media circulation space, and may open in the extension direction of the jet flow path. Furthermore, the first straight pipe section, the second straight pipe section and the curved pipe section may be integrally molded by three-dimensional additive manufacturing. Effect of the Invention

[0009] According to the above configuration, it is possible to provide a blast gun for a blasting device having a curved pipe section that switches the traveling direction of the blasting media, which can more effectively suppress uneven wear in the portion through which the blasting media flows. [Brief description of the drawings]

[0010] [Figure 1] FIG. 1 is a perspective view of a blast gun according to one embodiment. [Diagram 2] FIG. 2 is a cross-sectional view of a blast gun according to one embodiment. [Diagram 3] FIG. 3 is a perspective view of a blast gun according to some embodiments. [Figure 4] FIG. 4 is a cross-sectional view of a blast gun according to some embodiments. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0011] Hereinafter, some exemplary embodiments will be described with reference to the drawings. Here, the dimensions, materials, and other specific numerical values ​​shown in each embodiment are merely examples and do not limit the present disclosure unless otherwise specified. In addition, elements having substantially the same functions and configurations are given the same or similar symbols to avoid repeated explanations, and elements not directly related to the present disclosure are not illustrated.

[0012] (First embodiment) FIG. 1 is a perspective view of a blast gun 1 according to the first embodiment. The blast gun 1 is provided in a blasting device that performs blast processing on a workpiece, and uses compressed air CA to spray blast media BM such as abrasive grains onto the workpiece. During blast processing, an operator holds the blast gun 1 in one hand, directs the nozzle 32 of the blast gun 1 toward the workpiece surface on the workpiece, and sprays the blast media BM from the nozzle 32. Alternatively, the blast gun 1 may be held by a robot equipped with, for example, multiple movable arms, and automatically moves to the vicinity of the workpiece surface to spray the blast media BM. Note that the components of the blasting device other than the blast gun 1 may be the same as the components of a general blasting device, and therefore illustrations and detailed descriptions are omitted.

[0013] The blast gun 1 has a first straight pipe section 10, a second straight pipe section 11, and a curved pipe section 12 connecting the first straight pipe section 10 and the second straight pipe section 11 as a main body section. In this embodiment, the first straight pipe section 10, the second straight pipe section 11, and the curved pipe section 12 are integral with each other. The blast gun 1 may have a media introduction section 13 to which the blast media BM is supplied from one end side of the first straight pipe section 10. Note that, here, the one end side of the first straight pipe section 10 is the end side opposite to the end connected to the curved pipe section 12. The blast gun 1 may also have an air connection pipe section 14 for connecting an air supply tube that supplies compressed air CA from the outside to the first straight pipe section 10. The blast gun 1 may also have a grip section that an operator holds when holding the blast gun 1. The grip portion may be manufactured separately from the main body portion having the first straight pipe portion 10 and the like, and then finally connected to the main body portion, or may be integral with the main body portion in advance.

[0014] Fig. 2 is a cross-sectional view of the blast gun 1. The cross section in Fig. 2 is along a plane defined by a plane including an extension direction D1 of the first straight pipe section 10 of the main body and an extension direction D2 of the second straight pipe section 11.

[0015] The first straight pipe section 10 extends in the extension direction D1 in the figure, and is a major part of the parts constituting the main body. The first straight pipe section 10 includes a media flow path 20 and an air flow path 21 inside. The media flow path 20 distributes the blast media BM introduced from the outside. The air flow path 21 is disposed within the media flow path 20, and distributes the compressed air CA introduced from the outside. In this embodiment, the media flow path 20 and the air flow path 21 extend within the first straight pipe section 10 along the extension direction D1 of the first straight pipe section 10. Furthermore, the media flow path 20 and the air flow path 21 are parallel to each other in at least a part of the first straight pipe section 10.

[0016] Here, the air flow path 21 is a flow path for circulating the compressed air CA, and the outer diameter of the air flow path 21 is smaller than the inner diameter of the media flow path 20. Furthermore, the cross-sectional shape of each of the media flow path 20 and the air flow path 21 does not necessarily have to be circular, and may be elliptical or the like.

[0017] In addition, a media introduction section 13 is provided on the side wall 10a at one end of the first straight pipe section 10 to introduce the blast media BM from the outside into the media flow path 20. Here, the one end of the first straight pipe section 10 is the end opposite to the side connected to the curved pipe section 12. The media introduction section 13 is a cylindrical body having a through passage 25 inside. The media introduction section 13 has a media introduction port 30 as an end opposite to the side connected to the side wall 10a of the through passage 25. The media introduction section 13 extends in a direction intersecting the extension direction D1 of the first straight pipe section 10 from the side connected to the side wall 10a to the end on the side where the media introduction port 30 is formed. The through passage 25 communicates with the media flow path 20 at the position where the media introduction section 13 connects to the first straight pipe section 10.

[0018] Therefore, when the blast media BM is introduced from the outside into the media inlet 30, the blast media BM flows through the through passage 25 and is introduced into the media flow path 20. In this embodiment, the media inlet section 13 is formed in advance so as to be integrated with the main body section having the first straight pipe section 10 etc. However, the media inlet section 13 may also be manufactured as a separate body and finally connected to the main body section.

[0019] Furthermore, an air connection pipe section 14 is provided at one end 10b of the first straight pipe section 10 to introduce compressed air CA from the outside into the air flow path 21. Here, the one end 10b of the first straight pipe section 10 refers to the end opposite to the side connected to the curved pipe section 12. The air connection pipe section 14 is a cylindrical body having a through passage 26 therein. The air connection pipe section 14 has an air inlet 31 as an end opposite to the side connected to the one end 10b of the first straight pipe section 10 of the through passage 26. The through passage 26 communicates with the upstream end of the air flow path 21. In this embodiment, the air connection pipe section 14 is connected in series to the first straight pipe section 10 so that the central axis of the through passage 26 is coaxial with the central axis of the air flow path 21.

[0020] Therefore, when compressed air CA is introduced from the outside into the air inlet 31, the compressed air CA flows through the through passage 26 and is introduced into the air flow path 21. In this embodiment, the air connection pipe portion 14 is formed in advance so as to be integrated with the main body portion having the first straight pipe portion 10 and the like. However, the air connection pipe portion 14 may be manufactured as a separate body and finally connected to the main body portion.

[0021] 2, the second straight pipe section 11 extends in an extension direction D2, and is a tip portion of the portion constituting the main body of the blast gun 1. The second straight pipe section 11 includes an ejection flow path 22 therein that circulates the blast media BM delivered from the first straight pipe section 10 and guides it to the ejection port 32. The extension direction of the ejection flow path 22 is aligned with the extension direction D2 of the second straight pipe section 11. In this embodiment, the diameter of the ejection flow path 22 is set smaller than the diameter of the media flow path 20.

[0022] The curved pipe section 12 connects the first straight pipe section 10 and the second straight pipe section 11. The curved pipe section 12 includes a curved flow path 24 in which the media flow path 20 and the air flow path 21 are bent so that the extension direction D1 of the first straight pipe section 10 and the extension direction D2 of the second straight pipe section 11 are different directions. In other words, the blasting media BM that has flowed through the media flow path 20 is guided to the ejection flow path 22 through the curved flow path 24 and is finally discharged to the outside from the ejection port 32. In this embodiment, the diameter of the curved flow path 24 is set to be the same as the diameter of the media flow path 20. The first straight pipe section 10 and the second straight pipe section 11 are connected through the curved pipe section 12, so that the extension direction D2 of the second straight pipe section 11 and the ejection flow path 22 is inclined by a first angle θ1 with respect to the extension direction D1 of the first straight pipe section 10 and the media flow path 20. The first angle θ1 is in the range of 1° to 90°.

[0023] The blast gun 1 also has a suction area 40 that sucks in the blast media BM from the media flow path 20 by compressed air CA that has flowed through the air flow path 21, and delivers the blast media BM to the injection port 32 as a mixed fluid.

[0024] In this embodiment, the suction area 40 is formed in a part of the second straight pipe section 11. In the suction area 40, an air nozzle 41 provided at the downstream end of the air flow path 21 and a media circulation space 42 provided at the downstream end of the media flow path 20 are arranged.

[0025] The air flow path 21 is separated from the inner peripheral surface of the media flow path 20 at least from the bent flow path 24. The central axis of the air nozzle 41 provided at the downstream end of the air flow path 21 arranged in the second straight pipe section 11 may be arranged coaxially with the central axis of the media flow path 20 in the second straight pipe section 11. In this embodiment, the outer peripheral surface of the air flow path 21 is separated from the inner peripheral surface of the media flow path 20 from the flow path arranged in the first straight pipe section 10 to the air nozzle 41 provided at the downstream end of the air flow path 21. Therefore, the outer peripheral surface of the air flow path 21 is separated from the inner peripheral surface of the media flow path 20 over a wider range than from the bent flow path 24 to the second straight pipe section 11. Specifically, the air flow path 21 is arranged coaxially with the media flow path 20 from the flow path arranged in the first straight pipe section 10 to the air nozzle 41 provided at the downstream end of the air flow path 21. However, the air nozzle 41 provided at the downstream end of the air flow path 21 does not necessarily have to be arranged coaxially with the media flow path 20 in the second straight pipe section 11. The air nozzle 41 only needs to be arranged at a position in the suction region 40 where the blasting media BM is not pulled at the wall of the media flow path 20 in the second straight pipe section 11. In other words, the air nozzle 41 at the downstream end of the air flow path 21 only needs to be arranged at a position in the second straight pipe section 11 where uneven wear on the inner circumferential surface of the media flow path 20 caused by the blasting media BM sucked in within the suction region 40 can be suppressed.

[0026] In other words, this embodiment has a double pipe structure in which the media flow path 20 is an outer pipe and the air flow path 21 is an inner pipe.

[0027] In the embodiment, the air flow path 21, which is the inner pipe, is supported by a plurality of support ribs 50 within the media flow path 20, which is the outer pipe. Specifically, the air flow path 21 is supported inside the media flow path 20 by a plurality of support ribs 50 from the upstream side where it connects to the air connection pipe portion 14 to the air nozzle 41. At this time, the air flow path 21 is supported such that the central axis of the air flow path 21 and the central axis of the media flow path 20 are coaxial.

[0028] 2, the support ribs 50 may be arranged at multiple locations in the extension direction at each portion of the blast gun 1. In this embodiment, the support ribs 50 are arranged at a total of four locations from the upstream side of the air flow passage 21 where it is connected to the air connection pipe portion 14 to the end portion on the air nozzle 41 side.

[0029] At each position in the extension direction where the support ribs 50 are arranged, a plurality of support ribs 50 may be arranged at equal intervals around the circumference in the portion between the media flow path 20 and the air flow path 21. In this embodiment, for example, a total of four support ribs 50 are arranged around the outer periphery of the air flow path 21, at 90 degree intervals around the circumference. Note that the number of support ribs 50 arranged around the circumference and the positions in the extension direction of the main body of the blast gun 1 where the support ribs 50 are arranged are not limited to this.

[0030] The shape of each support rib 50 is structured to stably support the air flow path 21 while reducing the effect on the flow of the blast media BM flowing in the media flow path 20. Specifically, each support rib 50 may have a structure in which the cross-sectional area perpendicular to the extension direction of the media flow path 20 is smaller on the upstream side of the media flow path 20 than on the downstream side.

[0031] In a cross section perpendicular to the stretching direction at a position where there is no support rib 50, the ratio of the cross-sectional area of ​​the air flow path 21 to the cross-sectional area of ​​the media flow path 20 can be set arbitrarily within a range in which a mixed fluid having the desired processing performance can be obtained. The ratio of the cross-sectional area of ​​the air flow path 21 to the cross-sectional area of ​​the media flow path 20 may be in the range of 0.1 to 1, for example.

[0032] In the suction region 40, the air nozzle 41 and the media circulation space 42 communicate with the ejection flow path 22. The extension direction of the nozzle flow path 41a in the air nozzle 41 is along the extension direction D2 of the ejection flow path 22. The downstream end of the nozzle flow path 41a, i.e., the tip opening 41b of the air nozzle 41, is arranged in the suction region 40 such that the outer peripheral region of the tip opening 41b becomes the media circulation space 42. The tip opening 41b of the air nozzle 41 opens in the extension direction D2 of the ejection flow path 22. Note that the suction region 40 may include at least a portion of the ejection flow path 22.

[0033] The second straight pipe section 11 may be set to have a short length in the extension direction D2 within a range in which a mixed fluid having desired processing performance during blast processing can be obtained in the suction region 40. By setting the length in the extension direction D2 to be short in this manner, even if the surface to be processed is in a narrowed portion, it becomes possible to perform blast processing by allowing the blasting pipe 11 to enter the narrowed portion without interfering with the workpiece.

[0034] 2, the diameter of the air nozzle 41 is set to be smaller than at least the diameter of the air flow path 21 arranged in the first straight pipe section 10. Note that the diameter of the air nozzle 41 may be set to be smaller than the diameter of the air flow path 21 arranged in the curved pipe section 12 as in this embodiment.

[0035] Furthermore, as shown in FIG. 2, the media flow path 20 may have a structure in which a media circulation space 42 is provided at the downstream end connected to the ejection flow path 22 and arranged in the suction area 40, and is connected to the ejection flow path 22 while narrowing in diameter.

[0036] The air flow path 21 may be molded integrally with the media flow path 20 and the support rib 50. The air flow path 21 may be formed separately from the media flow path 20. In this case, the air flow path 21 may be inserted from one end of the first straight pipe section 10 opposite to the end connected to the curved pipe section 12 and supported within the media flow path 20. In this case, the air flow path 21 may be supported within the media flow path 20 by a plurality of support ribs 50 provided on the media flow path 20 such that the tip opening 41b of the air nozzle 41 is positioned within the second straight pipe section 11.

[0037] Next, the effect of the blast gun 1 will be described.

[0038] The blast gun 1 ejects the blast media BM by using compressed air CA. The blast gun 1 has a first straight pipe section 10 including a media flow path 20 through which the blast media BM flows, and an air flow path 21 arranged in the media flow path 20 through which the compressed air CA flows. The blast gun 1 has a second straight pipe section 11 including an ejection flow path 22 through which the blast media BM sent out from the first straight pipe section 10 flows and leads it to an ejection port 32. The blast gun 1 has a curved pipe section 12 that connects the first straight pipe section 10 and the second straight pipe section 11, and includes a curved flow path 24 that is an area where the media flow path 20 and the air flow path 21 are bent so that the extension direction D1 of the first straight pipe section 10 and the extension direction D2 of the second straight pipe section 11 are different directions. The air flow path 21 of the blast gun 1 is separated from the inner peripheral surface of the media flow path 20 at least from the curved flow path 24. Within the second straight pipe section 11, the downstream end of the air flow path 21 and the downstream end of the media flow path 20 are connected to the injection flow path 22 to form a suction area in which the blast media BM is sucked in by compressed air CA and sent out to the injection port 32.

[0039] First, in the blast gun 1, the second straight pipe section 11 on the tip side, i.e., downstream side, is connected to the first straight pipe section 10 on the upstream side via the curved pipe section 12, so that even if the surface to be processed is in a narrowed portion of the workpiece, the second straight pipe section 11 can easily enter the narrowed portion of the workpiece. In addition, in the blast gun 1, the media flow path 20 and the air flow path 21 are both included in the first straight pipe section 10. Therefore, compared to a configuration in which, for example, a supply tube for blast media and a supply tube for compressed air are connected to each other from different directions, when the second straight pipe section 11 is inserted into the narrowed portion of the workpiece, the blast gun 1 is less likely to interfere with the workpiece. Therefore, according to the blast gun 1, even if the surface to be processed is in a narrowed portion of the workpiece, the second straight pipe section 11 can reach a desired position near the workpiece, making it easier to perform blast processing on the workpiece.

[0040] In this manner, according to this embodiment, it is possible to provide a blast gun 1 that performs blast processing on a processing surface located in a narrowed portion.

[0041] Generally, in a blast gun that sucks in and delivers blast media using compressed air, if there is a curved surface in the flow path from the suction area to the nozzle, the curved surface is easily worn away by the blast media, which is energized by the compressed air, being blown thereto. In contrast, in the blast gun 1 according to this embodiment, the suction area 40 is located within the second straight pipe section 11. In other words, the blast media BM delivered from the suction area 40 flows only through the straight-extending jet flow path 22 while heading toward the nozzle 32, and does not flow through the curved flow path 24 included in the curved pipe section 12. Therefore, according to the blast gun 1, it is possible to suppress wear of the flow portion of the blast media BM caused by the blast media BM being continuously blown thereto.

[0042] Thus, according to this embodiment, even in a blast gun 1 equipped with a curved pipe section 12 that switches the direction in which the blast media travels, it is possible to provide a blast gun 1 that can more effectively suppress uneven wear in the flow area of ​​the blast media BM.

[0043] Furthermore, the air nozzle 41 at the downstream end of the air flow path 21 arranged in the second straight pipe section 11 may be arranged coaxially with the media flow path 20. Therefore, in the blast gun 1, the collision angle of the blast media BM in the ejection flow path 22 extending along the extension direction D2 of the second straight pipe section 11 becomes shallow. This reduces uneven wear of the ejection flow path 22, such as wear of part of the wall surface around the circumference, in the range from the suction area 40 of the blast gun 1 to the ejection flow path 22. In addition, when the blast media BM is sucked into the compressed air CA in the suction area 40, the blast media BM is sucked from all directions around the air nozzle 41. Therefore, according to the configuration of the blast gun 1, the blast media BM sucked into the compressed air CA uniformly around the circumference can perform more uniform surface processing on the processing surface.

[0044] Furthermore, in the ejection port 32 and ejection flow path 22 of the blast media BM that can be used in the blast gun 1, uneven wear around the curved flow path 24 can be reduced without reducing the flow rate of the blast media BM. Therefore, with the blast gun 1, it is possible to achieve both high processing performance during blast processing and low uneven wear around the curved flow path 24 at a high level.

[0045] In the blast gun 1, the media flow path 20 and the air flow path 21 may extend in parallel with each other along the extension direction D1 of the first straight pipe section 10 in at least a part of the first straight pipe section 10.

[0046] According to this blast gun 1, when the first straight pipe section 10 is viewed in a cross section perpendicular to the extension direction D1, the cross-sectional shape of the first straight pipe section 10 can be made compact. In other words, even if the surface to be processed is in a narrowed portion of the workpiece, the blast gun 1 can be made less likely to interfere with the workpiece.

[0047] Furthermore, in the blast gun 1, the first straight pipe section 10 may have an air inlet 31 for introducing compressed air CA from the outside to the upstream side of the air flow path 21, and a media inlet 30 for introducing blast media BM from the outside to the upstream side of the media flow path 20. The air inlet 31 may be provided at one end 10b of the first straight pipe section 10 opposite to the end connected to the curved pipe section 12. Furthermore, the media inlet 30 may be provided in the side wall 10a of the first straight pipe section 10.

[0048] According to this blast gun 1, first, since the media inlet 30 is provided on the side wall 10a of the first straight pipe section 10, the shape of the media flow path 20 can be simplified or made small. As a result, in the blast gun 1, the cross-sectional shape of the air flow path 21 can be set relatively large, while avoiding the first straight pipe section 10 from becoming complicated or large in shape. On the other hand, since the air inlet 31 is provided on one end 10b of the first straight pipe section 10, the shape of the air flow path 21 can be avoided from becoming complicated, and as a result, the shape of the first straight pipe section 10 can be avoided from becoming complicated or large. Furthermore, since the air inlet 31 is provided so as to introduce the compressed air CA to the upstream side of the air flow path 21, the area in the first straight pipe section 10 where the media flow path 20 and the air flow path 21 extend in parallel to each other along the extension direction D1 is secured to be relatively wide. Therefore, even if the surface to be processed is in a narrowed portion of the workpiece, the blast gun 1 can be made less likely to interfere with the workpiece.

[0049] Furthermore, in the blast gun 1, the suction region 40 may have an air nozzle 41 continuous with the air flow path 21, and a media circulation space 42 continuous with the media flow path 20. Furthermore, the tip opening 41b of the air nozzle 41 may protrude into the curved flow path 24 so that the outer circumferential region of the tip opening 41b becomes the media circulation space 42, and may open in the extension direction D2 of the jet flow path 22. Here, the outer circumferential region of the tip opening 41b is the surface of the outer circumferential part where the tip opening 41b is provided, and is a part that defines part of the shape of the media circulation space 42.

[0050] According to this blast gun 1, as one example, it is possible to realize a configuration in which the suction area 40 is contained within a part of the area formed by the first straight pipe section 10, the second straight pipe section 11, and the curved pipe section 12, and it is also possible to realize a configuration in which the suction area 40 is generated within the second straight pipe section 11.

[0051] Furthermore, in the blast gun 1, the first straight pipe section 10, the second straight pipe section 11 and the curved pipe section 12 may be integrally molded by three-dimensional additive manufacturing.

[0052] For example, when attempting to mass-produce blast gun 1 at low cost, it is desirable to manufacture blast gun 1 as a single unit, but due to the configuration or shape of blast gun 1, it may be difficult to manufacture using conventional cutting processes, etc. In contrast, with this blast gun 1, it is molded as a single unit using a three-dimensional layered modeling device as an additive manufacturing device, which is advantageous in terms of cost reduction and mass production.

[0053] In this embodiment, the first straight pipe section 10, the second straight pipe section 11, and the curved pipe section 12 that constitute the main body of the blast gun 1 are integral with each other. However, depending on manufacturing constraints, the first straight pipe section 10, the second straight pipe section 11, and the curved pipe section 12 may be manufactured as separate bodies and then joined to each other by welding or the like.

[0054] Furthermore, in this embodiment, the media flow path 20 and the air flow path 21 are each included in the first straight pipe section 10. Here, as one example, the first straight pipe section 10 is a single member as shown in Figures 1 and 2, but it may also be a joint of two members, for example, a first member including the media flow path 20 and a second member including the air flow path 21.

[0055] When the first support rib 51 included in the plurality of support ribs 50 is provided at one end side in the extension direction of the first straight pipe section 10, it is possible to suppress vibration of the air flow path 21 that may occur when, for example, introducing the blasting medium BM into the first straight pipe section 10. Note that, here, the one end side in the extension direction of the first straight pipe section 10 refers to the end side opposite to the side connected to the curved pipe section 12.

[0056] Furthermore, when the second support rib 52 included in the plurality of support ribs 50 is provided on one end side of the second straight pipe section 11 in the extension direction D2, the orientation of the air nozzle 41 with respect to the ejection port 32 can be stabilized. In other words, the ejection direction of the blasting media BM ejected from the air nozzle 41 can be stabilized. Note that, here, the one end side of the second straight pipe section 11 in the extension direction D2 is the side connected to the curved pipe section 12.

[0057] Furthermore, in the suction region 40, the media flow path 20 may be connected to the jet flow path 22 while narrowing in diameter. With this configuration, the blast media BM is more efficiently sucked into the compressed air CA jetted from the air nozzle 41 in the suction region 40, thereby improving the processing performance during the blast process.

[0058] Second embodiment 3 is a perspective view of a blast gun 101 according to the second embodiment. The blast gun 101, like the blast gun 1 according to the first embodiment, is provided in a blasting device and injects blast media BM at a workpiece by using compressed air CA. Again, each component included in the blasting device other than the blast gun 101 may be the same as each component included in a general blasting device, and therefore illustrations and detailed descriptions are omitted.

[0059] The blast gun 101 has a first straight pipe section 110, a second straight pipe section 111, and a curved pipe section 112 as a main body section. In this embodiment, the first straight pipe section 110, the second straight pipe section 111, and the curved pipe section 112 are integral with each other. The blast gun 101 may include a media introduction section 113 to which the blast media BM is supplied from the upstream side of the first straight pipe section 110. The blast gun 101 may also include an air connection pipe section 114 for connecting an air supply tube that supplies compressed air CA from the outside to the first straight pipe section 110. The blast gun 101 may also include a grip section that is gripped when holding the blast gun 101, similar to the blast gun 1 according to the first embodiment.

[0060] Fig. 4 is a cross-sectional view of the blast gun 101. The cross section in Fig. 4 is along a plane defined by a plane including an extension direction D1 of the first straight pipe portion 110 and an extension direction D2 of the second straight pipe portion 111.

[0061] The first straight pipe section 110 extends in the extension direction D11 in the figure, and is a main part of the parts constituting the main body. The first straight pipe section 110 includes a media flow path 120 and an air flow path 121 inside. The media flow path 120 distributes the blast media BM introduced from the outside. The air flow path 121 is disposed in the media flow path 120, and distributes the compressed air CA introduced from the outside. In this embodiment, the media flow path 120 and the air flow path 121 extend in the first straight pipe section 110 along the extension direction D11 of the first straight pipe section 110. The media flow path 120 and the air flow path 121 are parallel to each other in at least a part of the first straight pipe section 110.

[0062] Here, the air flow path 121 is a flow path for circulating compressed air CA, and the outer diameter of the air flow path 121 is smaller than the inner diameter of the media flow path 120. Furthermore, the cross-sectional shape of each of the media flow path 120 and the air flow path 121 does not necessarily have to be circular, and may be elliptical or the like.

[0063] In addition, a media introduction section 113 is provided on the side wall 110a at one end of the first straight pipe section 110 to introduce the blast media BM from the outside into the media flow path 120. Here, the one end of the first straight pipe section 110 is the end opposite to the side connected to the curved pipe section 12. The media introduction section 113 is a cylindrical body having a through passage 125 inside. The media introduction section 113 has a media introduction port 130 as an end opposite to the side connected to the side wall 110a of the through passage 125. The media introduction section 113 extends in a direction intersecting the extension direction D11 of the first straight pipe section 110 from the side connected to the side wall 110a to the end on the side where the media introduction port 130 is formed. The through passage 125 communicates with the media flow path 120 at the position where the media introduction section 113 connects to the first straight pipe section 110.

[0064] Furthermore, the first straight pipe section 110 is provided with an air connection pipe section 114 that introduces compressed air CA from the outside into the air flow path 121. The air connection pipe section 114 is a cylindrical body having a through passage 126 therein. The air connection pipe section 114 has an air inlet 131 at an end opposite to the end where the through passage 126 is connected to one end 110b of the first straight pipe section 110. The through passage 126 communicates with the upstream end of the air flow path 121. In this embodiment, the air connection pipe section 114 is connected in series to the first straight pipe section 110 so that the central axis of the through passage 126 is, for example, coaxial with the central axis of the air flow path 121.

[0065] The second straight pipe section 111 extends in the extension direction D12 in the figure, and is the tip of the portion constituting the main body. The second straight pipe section 111 includes an ejection flow path 122 therein that circulates the blasting media BM sent out from the first straight pipe section 110 and guides it to the ejection port 132. The extension direction of the ejection flow path 122 is aligned with the extension direction D12 of the second straight pipe section 111.

[0066] The curved pipe section 112 connects the first straight pipe section 110 and the second straight pipe section 111. The curved pipe section 112 includes a curved flow path 124 in which the media flow path 120 and the air flow path 121 are curved so that the extension direction D11 of the first straight pipe section 110 and the extension direction D12 of the second straight pipe section 111 are different directions. In other words, the blasting media BM that has flowed through the media flow path 120 is guided to the ejection flow path 122 through the curved flow path 24, and is finally discharged to the outside from the ejection port 132. The first straight pipe section 110 and the second straight pipe section 111 are connected via the curved pipe section 112, so that the extension direction D12 of the second straight pipe section 111 and the ejection flow path 122 is inclined by the second angle θ11 with respect to the extension direction D11 of the first straight pipe section 110 and the media flow path 120. In this embodiment, the second angle θ11 is 90°, but the second angle θ11 may be any angle within the range of 1° to 90°.

[0067] The blast gun 101 also has a suction area 140 that sucks and sends out the blast media BM from the media flow path 120 by compressed air CA that has flowed through the air flow path 121. In this embodiment, the suction area 140 is formed in a part of the second straight pipe section 111.

[0068] The air flow path 121 is separated from the inner circumferential surface of the media flow path 120 at least from the bent flow path 124. The central axis of the air nozzle 141 provided at the downstream end of the air flow path 121 arranged in the second straight pipe section 111 may be arranged coaxially with the central axis of the media flow path 120 in the second straight pipe section 111. In this embodiment, the outer circumferential surface of the air flow path 121 is separated from the inner circumferential surface of the media flow path 120 from the bent flow path 124 to the air nozzle 141 provided at the downstream end of the air flow path 121, i.e., up to the second straight pipe section 11. Specifically, the air flow path 121 has one side in the circumference, which is the lower side in FIG. 4, in close contact with the media flow path 120 in the first straight pipe section 110. The air flow path 121 is separated from the inner circumferential surface of the media flow path 120 at the bent flow path 124. An air nozzle 141 provided at the downstream end of the air flow path 121 disposed in the second straight pipe section 111 is arranged coaxially with the media flow path 120. However, in this embodiment as well, similarly to the first embodiment, the air nozzle 141 provided at the downstream end of the air flow path 121 does not necessarily have to be arranged coaxially with the media flow path 120 in the second straight pipe section 111.

[0069] The blast gun 101 according to this embodiment has the same effects as the blast gun 1 according to the first embodiment. Moreover, unlike the first embodiment, the blast gun 101 omits or reduces the support ribs arranged in the media flow path 120. This results in a structure in which the flow of the blast media BM is less likely to be obstructed in the media flow path 120. Therefore, with the blast gun 101, the blast media BM can be more stably supplied to the compressed air CA in the suction region 140.

[0070] Also, in this embodiment, in order to provide a configuration that further stabilizes the orientation of the air nozzle 141, second support ribs that support the air nozzle 141 may be provided around the periphery of the air nozzle 141, similar to the second support ribs 52 in the first embodiment. Note that the number and arrangement of the support ribs to be provided, specifically the number of support ribs arranged around the periphery, the arrangement in the extension direction of the main body of the blast gun 1, etc. are not limited to the arrangement of the second support ribs 52 in the first embodiment.

[0071] Although some embodiments have been described, the embodiments can be modified or modified based on the above disclosure. All components of the above embodiments and all features described in the claims may be individually extracted and combined as long as they are not mutually inconsistent. [Explanation of symbols]

[0072] 1,101 Blast Gun 10,110 1st straight pipe section 10a,110a side wall 10b,110b One end 11,111 2nd straight pipe section 12,112 Bent pipe section 20,120 Media Channel 21,121 Air passage 22,122 Injection channel 24,124 Bent Channel 30,130 Media Inlet 31,131 Air inlet 40,140 suction area 41,141 Air nozzle 41b Tip opening 42 Media Distribution Space BM Blast Media CA Compressed Air D1, D11: Extension direction of the first straight pipe section D2, D12: Extension direction of the second straight pipe section

Claims

1. A blast gun that uses compressed air to spray blast media, a first straight pipe section including a media flow path through which the blast medium flows, and an air flow path disposed within the media flow path through which the compressed air flows; A second straight pipe section including an injection flow path through which the blasting medium delivered from the first straight pipe section flows and is guided to an injection port; a curved pipe section that connects the first straight pipe section and the second straight pipe section and includes a curved flow path that is a region where the media flow path and the air flow path are curved such that an extension direction of the first straight pipe section and an extension direction of the second straight pipe section are different directions, the air flow path is separated from at least the bent flow path and an inner circumferential surface of the media flow path, A blast gun wherein a suction area is provided within the second straight pipe section, in which a downstream end of the air flow path and a downstream end of the media flow path are connected to the injection flow path, and the blast media is sucked in by the compressed air and delivered to the injection port.

2. The blast gun according to claim 1 , wherein the downstream end of the air flow passage is disposed coaxially with the media flow passage in the second straight pipe section.

3. 3. The blast gun according to claim 1, wherein the media flow path and the air flow path extend in parallel to each other along an extension direction of the first straight pipe portion in at least a part of the first straight pipe portion.

4. The first straight pipe portion is an air inlet port for introducing the compressed air from the outside to an upstream side of the air flow path; a media inlet for introducing the blast media from an external source on an upstream side of the media flow path; The media inlet is provided in a side wall of the first straight pipe portion, The blast gun according to claim 1 or 2, wherein the air inlet is provided at an end of the first straight pipe portion opposite to a side where the first straight pipe portion is connected to the curved pipe portion.

5. The suction area includes: an air nozzle connected to the air flow path; a media flow space is disposed in the media passage and is continuous with the media flow path; 3. The blast gun according to claim 1, wherein a tip opening of the air nozzle protrudes into the curved flow path so that an outer peripheral area of ​​the tip opening becomes the media flow space, and opens in an extension direction of the injection flow path.

6. The blast gun according to claim 1 or 2, wherein the first straight pipe section, the second straight pipe section, and the curved pipe section are integrally molded by three-dimensional additive manufacturing.

7. The blast gun according to claim 3 , wherein the first straight pipe section, the second straight pipe section, and the curved pipe section are integrally molded by three-dimensional additive manufacturing.

8. The blast gun according to claim 4 , wherein the first straight pipe section, the second straight pipe section, and the curved pipe section are integrally molded by three-dimensional additive manufacturing.

9. The blast gun according to claim 5 , wherein the first straight pipe section, the second straight pipe section, and the curved pipe section are integrally molded by three-dimensional additive manufacturing.

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