Shot processing equipment

Abstract

To provide a shot processing device capable of suppressing leakage of powders and granules. [Solution] The shot processing apparatus comprises a cabinet defining a projection chamber, the cabinet having an opening that communicates with the projection chamber and opens toward the outer surface of a workpiece; a projection machine provided in the cabinet for projecting a projection material toward the outer surface of a workpiece through the opening; and a sealing structure provided along the opening edge of the opening. The sealing structure includes an elastic member provided on the portion of the opening edge that extends in a first direction along the central axis of the workpiece, and a plurality of drive units arranged in the first direction, each of which moves the elastic member forward and backward relative to the outer surface of the workpiece.

Description

Technical Field

[0001] The present disclosure relates to a shot processing device.

Background Art

[0002] Shot blasting devices for processing the outer surface of a cylindrical workpiece are known. For example, Patent Document 1 describes a cylindrical body polishing structure including a rotation mechanism for rotating a cylindrical body around its axis, a polishing device capable of ejecting abrasive materials toward the outer peripheral surface of the cylindrical body, and a moving mechanism for moving the polishing device along the outer peripheral surface of the cylindrical body in the axial direction of the cylindrical body.

Prior Art Documents

Patent Documents

[0003]

Patent Document 1

Summary of the Invention

Problems to be Solved by the Invention

[0004] In the cylindrical body polishing structure described in Patent Document 1, an elastic member is provided at the open end of a cabinet (hopper) to which a polishing device is attached, and the elastic member is pressed against the outer surface of the cylindrical body. When processing a tapered workpiece whose diameter decreases toward the tip, if the elastic member is pressed against the outer surface of the workpiece according to the large-diameter portion, the elastic member may not be sufficiently pressed against the outer surface of the workpiece at the small-diameter portion, and a gap may occur between the elastic member and the outer surface. In this case, there is a risk that particulate matter including the projected projectile leaks to the outside through the gap.

[0005] The present disclosure describes a shot processing device capable of suppressing leakage of particulate matter.

Means for Solving the Problems

[0006] A shot blasting apparatus according to one aspect of the present disclosure is an apparatus for blasting the outer surface of a cylindrical workpiece. The shot blasting apparatus comprises a cabinet, a projector, and a sealing structure. The cabinet defines a projection chamber and has an opening. The opening communicates with the projection chamber and opens toward the outer surface of the workpiece. The projector is provided in the cabinet and projects a blasting material toward the outer surface of the workpiece through the opening. The sealing structure is provided along the opening edge of the opening. The sealing structure includes an elastic member and a plurality of drive units. The elastic member is provided on the portion of the opening edge that extends in a first direction along the central axis of the workpiece. The plurality of drive units are arranged in the first direction and each moves the elastic member forward and backward relative to the outer surface of the workpiece. [Effects of the Invention]

[0007] According to each aspect and embodiment of this disclosure, leakage of powders and granules can be suppressed. [Brief explanation of the drawing]

[0008] [Figure 1] Figure 1 is a schematic diagram showing a shot processing system including a shot processing apparatus according to one embodiment. [Figure 2] Figure 2 is a perspective view showing the shot processing apparatus shown in Figure 1. [Figure 3] Figure 3 is a diagram illustrating the circulation path of the projection material. [Figure 4] Figure 4 is a side view showing the moving mechanism and tilting mechanism of the shot processing device shown in Figure 2. [Figure 5] Figure 5 is a front view showing the moving mechanism and tilting mechanism of the shot processing device shown in Figure 2. [Figure 6] Figure 6 is a schematic diagram showing the projection device shown in Figure 2. [Figure 7] Figure 7 is a plan view of the projection device shown in Figure 6. [Figure 8] Figure 8 is a plan view showing the upper seal structure included in the seal structure shown in Figure 6. [Figure 9]Figure 9 is a cross-sectional view taken along line IX-IX of Figure 8. [Figure 10] Figure 10 is a side view showing the side seal structure included in the seal structure shown in Figure 6. [Figure 11] Figure 11 is a front view of the side seal structure shown in Figure 10. [Figure 12] Figure 12 is a cross-sectional view taken along line XII-XII of Figure 11. [Figure 13] Figure 13 is a diagram for explaining the operating principle of the side seal structure shown in Figure 10. [Figure 14] Figure 14 is a diagram showing the lower seal structure included in the seal structure shown in Figure 6. [Figure 15] Figure 15 is a cross-sectional view taken along line XV-XV of Figure 14. [Figure 16] Figure 16 is a flowchart showing the shot processing method performed by the control device shown in Figure 1. [Figure 17] Figure 17 is a flowchart showing the attitude control in detail in Figure 16. [Figure 18] Figure 18 is a diagram for explaining the processing range of the workpiece shown in Figure 1. [Figure 19] Figure 19 is a diagram for explaining the initial position of the projection device shown in Figure 6. [Figure 20] Figure 20 is a diagram for explaining the measurement position of the projection device shown in Figure 6. [Figure 21] Figure 21 is a diagram for explaining the tilting of the projection device shown in Figure 6. [Figure 22] Figure 22 is a diagram for explaining the target position of the projection device shown in Figure 6.

Embodiments for Carrying Out the Invention

[0009] Hereinafter, embodiments of the present disclosure will be described in detail with reference to the drawings. In the description of the drawings, the same reference numerals are assigned to the same elements, and duplicate descriptions are omitted. In each figure, an XYZ coordinate system may be shown. The Y-axis direction is a direction that intersects (for example, is orthogonal to) the X-axis direction and the Z-axis direction. The Z-axis direction is a direction that intersects (for example, is orthogonal to) the X-axis direction and the Y-axis direction. Unless otherwise specified in the text, the X-axis direction refers to the lateral direction (the first direction), the Y-axis direction refers to the front-back direction, and the Z-axis direction refers to the up-down direction. A "plan view" is a view seen from above and refers to an XY plan view. A "side view" is a view seen from the side and refers to a YZ plan view. A "front view" is a view seen from the front and refers to an XZ plan view.

[0010] Referring to FIG. 1, a shot processing system including a shot processing apparatus according to an embodiment will be described. FIG. 1 is a configuration diagram schematically showing a shot processing system including a shot processing apparatus according to an embodiment.

[0011] The shot processing system 1 shown in FIG. 1 is a system for performing shot processing on the outer surface Wa of a cylindrical workpiece W. The workpiece W is a long and large-diameter cylindrical body (columnar body). The length along the central axis of the workpiece W (hereinafter referred to as "axis AX1") is, for example, 30 m to 40 m. The diameter of the workpiece W is, for example, 5 m to 10 m. The diameter of the workpiece W may be constant over the entire length of the workpiece W, or may decrease from one end to the other end. An example of the workpiece W is a tower for wind power generation. The shot processing system 1 includes a shot processing apparatus 10 and a rotation mechanism 100.

[0012] The shot processing apparatus 10 is an apparatus for performing shot processing on the outer surface Wa of the workpiece W. The shot processing apparatus 10 performs shot processing on the outer surface Wa while the workpiece W is being rotated around the axis AX1 of the workpiece W by the rotation mechanism 100. The shot processing apparatus 10 performs shot processing on the outer surface Wa for each processing range obtained by dividing the outer surface Wa along the axis AX1. The detailed configuration of the shot processing apparatus 10 will be described later.

[0013] The rotating mechanism 100 is a mechanism for rotating the workpiece W around the axis AX1. The rotating mechanism 100 includes a base 101 and turning rolls 102. The base 101 is placed on the floor and supports the turning rolls 102. In this embodiment, four turning rolls 102 are provided on the base 101. The four turning rolls 102 support the workpiece W so that it can rotate around the axis AX1. The four turning rolls 102 support the workpiece W so that the axis AX1 is substantially parallel to the floor. Each turning roll 102 is configured to rotate around an axis extending in the same direction as the axis AX1 by a drive motor (not shown). The workpiece W rotates around the axis AX1 as the four turning rolls 102 are driven to rotate in the same direction around the axis.

[0014] Next, the configuration of the shot processing device 10 will be described in detail with reference to Figures 2 to 5. Figure 2 is a perspective view showing the shot processing device shown in Figure 1. Figure 3 is a diagram illustrating the circulation path of the projectile material. Figure 4 is a side view showing the moving mechanism and tilting mechanism of the shot processing device shown in Figure 2. Figure 5 is a front view showing the moving mechanism and tilting mechanism of the shot processing device shown in Figure 2. In Figure 3, parts of the shot processing device 10 that are not closely related to the circulation path of the projectile material are omitted from the illustration. In Figures 4 and 5, parts of the shot processing device 10 that are not closely related to the moving mechanism and tilting mechanism are omitted from the illustration.

[0015] As shown in Figures 2 to 5, the shot processing device 10 includes a supply device 11, a projection device 12, a recovery device 13, a classification device 14, a moving mechanism 15, a tilting mechanism 16, and a control device 17 (see Figure 1).

[0016] The supply device 11 is a device that supplies abrasive material to the projection device 12. The supply device 11 is located above the projection device 12. The supply device 11 includes a abrasive material tank 11a and a gate 11b. The abrasive material tank 11a stores the abrasive material. The gate 11b is located below the abrasive material tank 11a and adjusts the amount of abrasive material flowing from the abrasive material tank 11a to the projection device 12.

[0017] The projection device 12 is a device that projects a projection material onto the outer surface Wa of the workpiece W. The projection device 12 projects the projection material onto the outer surface Wa while the workpiece W is rotating around axis AX1. The projection device 12 projects the projection material onto the region of the outer surface Wa where the outer surface Wa extends from bottom to top. The projection device 12 includes a cabinet 21, a projector 22, a receiving member 23, and a rotating shaft 24. The cabinet 21 is a box-shaped member that defines the projection chamber 21a. The size of the projection chamber 21a is determined considering the distance between the projector 22 and the outer surface Wa, the projection range, and the distribution. The cabinet 21 is configured to be tiltable around axis AX2 of the rotating shaft 24.

[0018] The cabinet 21 has an opening 21b on the surface facing the outer surface Wa. The opening 21b communicates with the projection chamber 21a and opens toward the outer surface Wa of the workpiece W. The opening 21b has a rectangular shape. The opening 21b only needs to be large enough to accommodate shot processing.

[0019] The projector 22 is installed in the cabinet 21 and projects the abrasive material onto the outer surface Wa of the workpiece W through the projection chamber 21a and the opening 21b. The projection method of the projector 22 may be air-powered or impeller-type (centrifugal). Examples of air-powered systems include gravity-powered, suction-powered, direct-pressure-powered (pressurized), and blower-type systems. In this embodiment, the impeller-type system will be used for explanation. Examples of abrasive materials include steel shot and steel grit. The type of abrasive material can be appropriately selected according to the required specifications for shot processing and the type of workpiece W.

[0020] The receiving member 23 is a member that receives the powder and granular material generated by the shot blasting process. The powder and granular material includes the projectile material used in the shot blasting process and cutting dust from the workpiece W generated by the shot blasting process. The receiving member 23 is provided so as to surround the lower part of the cabinet 21. An outlet 23a for discharging the powder and granular material is provided at the bottom of the receiving member 23. The receiving member 23 includes a conveying screw 23b provided above the outlet 23a. The conveying screw 23b collects the powder and granular material that has fallen to the bottom of the receiving member 23 at the outlet 23a and discharges it from the outlet 23a. The detailed configuration of the projection device 12 will be described later.

[0021] The recovery device 13 is a device for recovering the powder and granular material generated by the shot blasting process. The recovery device 13 recovers the powder and granular material discharged from the discharge port 23a and supplies the recovered powder and granular material to the classification device 14. The recovery device 13 includes a screw conveyor 13a and a bucket elevator 13b.

[0022] The screw conveyor 13a is located below the projection device 12 and extends horizontally. The screw conveyor 13a receives the granular material generated by the shot processing from the projection device 12 and transports it toward the bucket elevator 13b. The screw conveyor 13a includes a shaft and blades arranged spirally on the outer surface of the shaft. As the shaft rotates, the granular material is transported by the blades. The bucket elevator 13b transports the granular material that has been transported by the screw conveyor 13a to the classifier 14. The bucket elevator 13b circulates multiple buckets. Each bucket scoops up the granular material, transports it upward, and supplies it to the classifier 14.

[0023] The classifier 14 is a device that separates reusable abrasive material from the powder supplied from the recovery device 13. The classifier 14 is located above the supply device 11 and supplies the reusable abrasive material to the supply device 11.

[0024] The moving mechanism 15 is a mechanism that moves the projection device 12 in a direction along the axis AX1 (hereinafter sometimes referred to as the "lateral direction") and in a direction that intersects (here, perpendicular to) the lateral direction (hereinafter sometimes referred to as the "forward-backward direction"). In this embodiment, the moving mechanism 15 moves the supply device 11, projection device 12, recovery device 13, classification device 14, and tilting mechanism 16 as a single unit. The moving mechanism 15 includes a rail 15a, a trolley 15b, a rail 15c, a trolley 15d, and a cylinder 15e.

[0025] Rail 15a is laid on the floor surface and extends substantially parallel to the axis AX1. Trolley 15b travels on rail 15a. Trolley 15b moves laterally, for example, by motor drive. Rail 15c extending in the front-rear direction is laid on the upper surface of trolley 15b. Trolley 15d travels on rail 15c. Trolley 15d moves in the front-rear direction by cylinder 15e installed on trolley 15b. Note that the configuration of the moving mechanism 15 is not limited to the above configuration, and it is sufficient as long as the supply device 11, projection device 12, recovery device 13, classification device 14, and tilting mechanism 16 can be moved integrally in the front-rear and front-rear directions.

[0026] The tilting mechanism 16 is a mechanism that tilts the projection device 12 around the rotation axis 24. In other words, the tilting mechanism 16 tilts the projection device 12 around the axis AX2 of the rotation axis 24. The tilting mechanism 16 includes a pair of support members 16a and a cylinder 16b. The pair of support members 16a are erected on the upper surface of the trolley 15d and support both ends of the rotation axis 24 so that the rotation axis 24 can rotate around the axis AX2. The cylinder 16b is mounted on the trolley 15d so as to be rotatable around an axis extending laterally. The cylinder 16b has a piston rod that can move back and forth in the front-rear direction. Below the rotation axis 24, the tip of the piston rod is connected to the back of the projection device 12. The cylinder 16b tilts (rotates) the projection device 12 around the axis AX2 by moving the piston rod back and forth.

[0027] The control device 17 is a device (controller) that provides overall control of the shot processing device 10. The control device 17 is configured as a computer that includes, for example, a processor such as a CPU (Central Processing Unit), memory such as RAM (Random Access Memory) and ROM (Read Only Memory), and communication devices such as a network card. The control device 17 may also be configured as a PLC (Programmable Logic Controller). The control device 17, for example, controls the attitude of the projection device 12 and causes the projection material to be projected onto the projection device 12 whose attitude has been controlled. The shot processing method performed by the control device 17 will be described later.

[0028] In the shot processing apparatus 10, abrasive material is supplied from the abrasive material tank 11a to the projector 22 through the gate 11b, and the projector 22 projects the abrasive material onto the outer surface Wa of the workpiece W through the projection chamber 21a and the opening 21b. This applies shot blasting to the outer surface Wa. The powder generated by the shot blasting is collected in the projection chamber 21a and falls from the projection chamber 21a into the receiving member 23 through the gap 21g (see Figure 6), which will be described later. The powder that falls into the receiving member 23 is collected at the discharge port 23a by the conveying screw 23b and discharged from the discharge port 23a. The powder discharged from the discharge port 23a is then supplied to the classifier 14 via the screw conveyor 13a and the bucket elevator 13b. In the classifier 14, the powder is separated into reusable abrasive material and dust, and the reusable abrasive material is supplied to the abrasive material tank 11a.

[0029] Next, the configuration of the projection device 12 will be described in detail with reference to Figures 5 to 7. Figure 6 is a schematic diagram showing the projection device shown in Figure 2. Figure 7 is a plan view of the projection device shown in Figure 6. In Figure 7, the seal structure 25 and other components, which will be described later, are omitted from the illustration.

[0030] As shown in Figures 5 to 7, the cabinet 21 includes a top panel 211, a pair of side panels 212, a back panel 213, and a pair of inclined panels 214. The pair of side panels 212 face each other in the lateral direction. The back panel 213 faces the opening 21b in the front-to-back direction. The back panel 213 is bent in a V-shape that curves backward so as to be symmetrical with respect to the center in the lateral direction. The bending angle of the back panel 213 is set so that the projection density is uniform, taking into account the projection range and distribution.

[0031] A pair of inclined plates 214 are located below the top plate 211 and are inclined so that they move closer to each other in the front-to-back direction as they descend. The projection chamber 21a is defined by the top plate 211, a pair of side plates 212, a back plate 213, and a pair of inclined plates 214. The opening 21b is defined by the front end of the top plate 211, the front end of the pair of side plates 212, and the front end of the front inclined plate 214. Liners (wear-resistant steel plates) are provided on the inner surface of the cabinet 21.

[0032] The back panel 213 is provided with a projection port 21c, an intake port 21d, and an exhaust port 21e. A projector 22 is attached to the projection port 21c, and projection material is projected from the projector 22 into the projection chamber 21a via the projection port 21c. In this embodiment, two projection ports 21c are provided. One projection port 21c is located on the right side of the back panel 213, and the other projection port 21c is located on the left side of the back panel 213. The lateral projection range Rs1 of the projection material projected from one projector 22 and the lateral projection range Rs2 of the projection material projected from the other projector 22 overlap each other in a plan view (viewed from above). To avoid interference between the projection material projected from the two projectors 22, the vertical positions (heights) of the two projection ports 21c may be different from each other.

[0033] The intake port 21d is an opening for drawing air into the projection chamber 21a from outside the chamber. In this embodiment, the intake port 21d is located in the center of the rear panel 213 of the cabinet 21 in the lateral direction. The discharge port 21e is an opening for discharging some of the powder (dust) generated by the shot blasting process from inside the projection chamber 21a. In this embodiment, two discharge ports 21e are located in symmetrical positions.

[0034] The cabinet 21 has a pair of inclined surfaces 21f located below the opening 21b. The pair of inclined surfaces 21f are the inner surfaces of a pair of inclined plates 214, and are inclined to move closer to each other as they extend downward. The lower ends of the pair of inclined surfaces 21f are spaced apart from each other, forming a gap 21g. The inclination angle of the inclined surfaces 21f is set to an angle that makes it difficult for powder and granular material generated by shot blasting to accumulate on the inclined surfaces 21f within the tilting range of the projection device 12. The powder and granular material generated by shot blasting falls from the projection chamber 21a into the receiving member 23 through the gap 21g.

[0035] As shown in Figure 6, the projection device 12 further includes a sealing structure 25. The sealing structure 25 is a structure for preventing granular material generated by shot blasting from leaking to the outside of the projection chamber 21a. The sealing structure 25 is provided along the opening edge of the opening 21b. The sealing structure 25 includes an upper sealing structure 30 (see Figure 8), a side sealing structure 40 (see Figure 10), and a lower sealing structure 50 (see Figure 14). The detailed configuration of the sealing structure 25 will be described later.

[0036] The projection device 12 further includes distance sensors 26a (first distance sensor), 26b (second distance sensor), 26c (third distance sensor), and 26d (fourth distance sensor). Each of the distance sensors 26a to 26d is mounted on the back panel 213 of the cabinet 21 and measures the distance to the outer surface Wa through the opening 21b. Distance sensors 26a and 26b are spaced apart from each other in the vertical direction. Distance sensors 26c and 26d are spaced apart from each other in the vertical direction. Distance sensor 26c is spaced apart from distance sensor 26a in the horizontal direction. Distance sensor 26d is spaced apart from distance sensor 26b in the horizontal direction.

[0037] The sensor set of distance sensors 26a and 26b (first sensor set) is located on the right side of the opening 21b when viewed from the front, and the sensor set of distance sensors 26c and 26d (second sensor set) is located on the left side of the opening 21b when viewed from the front. The distance from distance sensor 26a to the opening 21b, the distance from distance sensor 26b to the opening 21b, the distance from distance sensor 26c to the opening 21b, and the distance from distance sensor 26d to the opening 21b are substantially the same. Each of the distance sensors 26a to 26d transmits the measured distance (measured value) to the control device 17. The control device 17 controls the attitude of the projection device 12 based on the measured values ​​from the distance sensors 26a to 26d. Details of the attitude control will be described later.

[0038] The projection device 12 further includes a foreign object detection device 27. The foreign object detection device 27 is a device that detects foreign objects present on the outer surface Wa of the workpiece W. The foreign object detection device 27 is attached to the receiving member 23. Specifically, the foreign object detection device 27 is provided upstream of the opening 21b in the rotational direction of the workpiece W.

[0039] The foreign object detection device 27 includes, for example, a rod-shaped member protruding toward the outer surface Wa, and a limit switch connected to the rod-shaped member. When the workpiece W is rotating, if a foreign object is present on the outer surface Wa, the foreign object hits the tip of the rod-shaped member. This causes the rod-shaped member to be lifted, and the limit switch is switched from the off state to the on state. When the limit switch is turned on, a detection signal indicating that a foreign object has been detected is transmitted to the control device 17.

[0040] The control device 17 stops the shot processing when it detects foreign matter. Specifically, the control device 17 stops the rotating mechanism 100 and the shot processing device 10. The control device 17 may also retract the projection device 12 to the initial position described later when it detects foreign matter.

[0041] The projection device 12 further includes an inspection device 28. The inspection device 28 is a device for inspecting the condition of the outer surface Wa of the workpiece W. The inspection device 28 is mounted on the top plate 211 of the cabinet 21. Specifically, the inspection device 28 is located downstream of the opening 21b in the rotational direction of the workpiece W. In this embodiment, the inspection device 28 includes a surface roughness measuring instrument 28a and a camera 28b. The surface roughness measuring instrument 28a measures the surface roughness of the outer surface Wa and transmits the measured value to the control device 17 as an inspection result. The camera 28b photographs the outer surface Wa and transmits the image of the outer surface Wa to the control device 17 as an inspection result.

[0042] The control device 17 may change the processing conditions for shot processing according to the inspection results from the inspection device 28. For example, if the control device 17 determines from the image that the projection density is insufficient, it increases the projection density by increasing the set value of the projection amount or by decreasing the rotation speed of the workpiece W. If the control device 17 determines from the image that the projection density is excessive, it decreases the projection density by decreasing the set value of the projection amount or by increasing the rotation speed of the workpiece W.

[0043] The control device 17 increases the surface roughness of the abrasive material by increasing the particle size when the surface roughness of the outer surface Wa is low. The control device 17 may also increase the particle size of the abrasive material by having the supply device 11 supply larger size abrasive material and extracting a portion of the abrasive material circulating in the shot processing device 10. Similarly, the control device 17 decreases the surface roughness of the outer surface Wa by decreasing the particle size of the abrasive material when the surface roughness of the outer surface Wa is high.

[0044] Next, the upper seal structure 30 will be described in detail with reference to Figures 8 and 9. Figure 8 is a plan view showing the upper seal structure included in the seal structure shown in Figure 6. Figure 9 is a cross-sectional view along the line IX-IX in Figure 8.

[0045] As shown in Figures 8 and 9, the upper seal structure 30 is provided along the laterally extending upper edge of the opening edge of the opening 21b. The upper edge of the opening edge of the opening 21b corresponds to the front end of the top plate 211. The upper seal structure 30 includes a plurality of cylinders 31 (drive units), a plurality of guide members 32, a plurality of brackets 33, a plurality of brushes 34 (brush parts), a plurality of elastic bodies 35, and an elastic member 36.

[0046] In this embodiment, the upper seal structure 30 includes three cylinders 31. The three cylinders 31 are installed on the upper surface of the top plate 211 and are arranged laterally. The upper seal structure 30 includes the same number of guide members 32 as the cylinders 31. A guide member 32 is provided for each cylinder 31 and is arranged on the upper surface of the top plate 211, laterally aligned with the corresponding cylinder 31. Each cylinder 31 is configured to have a piston rod that can move back and forth in the front-rear direction. Each guide member 32 is configured to have a guide rod that can move back and forth in the front-rear direction. A single bracket 33 is commonly attached to the tip of the piston rod of the cylinder 31 and the tip of the guide rod of the guide member 32 corresponding to the cylinder 31. As a result, the guide rod of the guide member 32 moves back and forth in conjunction with the movement of the piston rod of the corresponding cylinder 31.

[0047] Each bracket 33 is fitted with one brush 34 and one elastic body 35. In other words, a brush 34 and an elastic body 35 are provided for each bracket 33. Specifically, the base end of the brush 34 is fixed to the bracket 33 so as to be rotatable around an axis extending in the direction normal to the upper surface of the top plate 211 (a direction intersecting the axis AX1 and the direction of movement of the brush 34), and the bristles of the brush 34 extend forward from the base end.

[0048] The elastic body 35 is positioned downstream of the brush 34 in the rotational direction of the workpiece W. The base end of the elastic body 35 is fixed to the bracket 33, and the tip of the elastic body 35 extends forward. The tip of the elastic body 35 protrudes further forward than the tip of the brush 34. The elastic body 35 is harder than the elastic member 36. The elastic body 35 is, for example, urethane rubber.

[0049] A single elastic member 36 is commonly fixed to the three brackets 33. The elastic member 36 is a plate material bent into a convex U-shape toward the front (outer surface Wa of the workpiece W). The elastic member 36 is made of wear-resistant rubber and is flexible. Examples of constituent materials for the elastic member 36 include butadiene rubber, styrene-butadiene rubber, urethane rubber, nitrile rubber, and ethylene propylene rubber. The elastic member 36 is positioned upstream of the brush 34 in the rotational direction of the workpiece W, extends forward from the three brackets 33, and is bent back in a U-shape to sandwich the front end of the top plate 211 in the vertical direction, extending backward. One end of the elastic member 36 is fixed to the three brackets 33, and the other end of the elastic member 36 is fixed to the underside of the top plate.

[0050] The elastic member 36 is provided at the front end of the top plate 211. Specifically, the elastic member 36 is provided at the front end of the top plate 211, extending along the entire length of the top plate 211 in the lateral direction. The front end of the top plate 211 is sandwiched vertically by the U-shaped bent elastic member 36. The brush 34 is located outside the cabinet 21, beyond the elastic member 36. The elastic body 35 is located outside the cabinet 21, beyond the brush 34.

[0051] Each cylinder 31 advances its piston rod until the protrusion of the elastic member 36 contacts the outer surface Wa of the workpiece W, thereby pressing the elastic member 36 against the outer surface Wa along the entire length of the front end of the top plate 211. In other words, each cylinder 31 moves the elastic member 36 back and forth relative to the outer surface Wa of the workpiece W. The multiple brushes 34 are moved back and forth relative to the outer surface Wa of the workpiece W by the multiple cylinders 31.

[0052] Next, the side seal structure 40 will be described in detail with reference to Figures 10 to 13. Figure 10 is a side view showing the side seal structure included in the seal structure shown in Figure 6. Figure 11 is a front view of the side seal structure shown in Figure 10. Figure 12 is a cross-sectional view along line XII-XII in Figure 11. Figure 13 is a diagram for explaining the operating principle of the side seal structure shown in Figure 10. In Figure 10, the upper seal structure 30 and the lower seal structure 50 are omitted from the illustration.

[0053] As shown in Figures 10 to 12, the side seal structure 40 is provided along the vertically extending side edge of the opening edge of the opening 21b. The side edge of the opening edge of the opening 21b corresponds to the front end of the side plate 212. The side seal structure 40 includes a cylinder 41 (drive unit), a guide member 42, a bracket 43, a magnet unit 44, a liner 45, a brush 46, and a roller 47 (positioning member).

[0054] The cylinder 41 is mounted on the outer surface of the side plate 212. The guide member 42 is positioned vertically alongside the cylinder 41. The cylinder 41 is configured so that its piston rod can move back and forth in the front-rear direction. The guide member 42 is configured so that its guide rod can move back and forth in the front-rear direction. A single bracket 43 is commonly attached to the tip of the piston rod of the cylinder 41 and the tip of the guide rod of the guide member 42. As a result, the guide rod of the guide member 42 moves back and forth in conjunction with the movement of the piston rod of the cylinder 41.

[0055] The bracket 43 is a plate-shaped member that extends vertically. The bracket 43 includes a central portion 43a, an inner portion 43b, and an outer portion 43c. The central portion 43a is located in front of the front end of the side plate 212 and extends laterally from the inside to the outside of the projection chamber 21a. The inner portion 43b extends rearward from the inner end of the central portion 43a. The outer portion 43c is inclined to move rearward as it extends outward from the outer end of the central portion 43a.

[0056] The bracket 43 is fitted with a magnet unit 44, a liner 45, a brush 46, and a roller 47. Specifically, the magnet unit 44 is fitted to the central portion 43a, the liner 45 is fitted to the inner portion 43b, and the brush 46 is fitted to the outer portion 43c. In other words, the liner 45 is located inside the cabinet 21 beyond the magnet unit 44, and the brush 46 is located outside the cabinet 21 beyond the magnet unit 44. The brush 46 is provided along the outer portion 43c. Specifically, the base end of the brush 46 is fitted to the outer portion 43c, and the brush 46 extends forward from the outer portion 43c, sloping laterally to the front of the magnet unit 44.

[0057] The magnet unit 44 is provided at the front end of the side plate 212 via a cylinder 41 and a bracket 43. The magnet unit 44 includes a plurality of magnets 44a (first magnets) and a plurality of magnets 44b (second magnets). The plurality of magnets 44a are arranged in the vertical direction. The plurality of magnets 44b are also arranged in the vertical direction and are positioned side by side with the plurality of magnets 44a in the horizontal direction.

[0058] Each magnet 44b is positioned to span across two magnets 44a that are adjacent to each other in the vertical direction among the multiple magnets 44a. In other words, each magnet 44b is positioned to overlap with the gap 44c between two magnets 44a that are adjacent to each other in the vertical direction when viewed from the side. The gap 44c is the portion of the arrangement of the multiple magnets 44a where no magnets 44a are provided.

[0059] Each magnet 44a is positioned to span across two magnets 44b that are adjacent to each other in the vertical direction among the multiple magnets 44b. In other words, each magnet 44a is positioned so as to overlap with the gap 44d between two magnets 44b that are adjacent to each other in the vertical direction when viewed from the side. The gap 44d is the portion of the arrangement of the multiple magnets 44b where no magnets 44b are provided.

[0060] Each magnet 44a and each magnet 44b may be provided with a wear-preventing cover. The cover is made of, for example, a stainless steel plate. The presence of the cover makes it easier to remove the projection material that has adhered to the magnet unit 44 during maintenance.

[0061] The liner 45 is a wear-resistant steel plate that extends in the vertical direction. Examples of materials used to construct the liner 45 include high-manganese steel and high-chromium steel. The magnet unit 44 and the liner 45 may be bent to conform to the outer surface Wa of the workpiece W.

[0062] The roller 47 is a component for determining the position of the magnet unit 44 relative to the outer surface Wa of the workpiece W. In this embodiment, the side seal structure 40 includes two rollers 47. The two rollers 47 are spaced apart in the vertical direction. The upper roller 47 is located above the magnet unit 44, and the lower roller 47 is located below the magnet unit 44. The front ends of the two rollers 47 are located substantially in the same position in the front-rear direction. The front ends of the two rollers 47 are located in front of the magnets 44a and 44b.

[0063] The cylinder 41 moves the magnet unit 44 forward and backward relative to the outer surface Wa. When the magnet unit 44 moves forward toward the outer surface Wa by the cylinder 41 and the front end of the roller 47 comes into contact with the outer surface Wa, the forward movement of the side seal structure 40 is stopped. As a result, a gap 48 (see Figure 13) is formed between the magnet unit 44 and the outer surface Wa.

[0064] As shown in Figure 13, projection material M in the projection chamber 21a may enter the gap 48. At this time, in the gap 48, the projection material M is attracted to the magnet unit 44 and accumulates on the surface of the magnet unit 44. The distance Dm between the magnet unit 44 and the outer surface Wa is set to the length over which the magnetic force (attraction force) of the magnet unit 44 extends. As a result, a layer of projection material M is formed in the gap 48, and the gap 48 is sealed by the projection material M. When a layer of projection material M is formed, the possibility of the projection material M leaking out of the gap 48 to the outside of the projection chamber 21a is reduced.

[0065] Next, the lower seal structure 50 will be described in detail with reference to Figures 14 and 15. Figure 14 is a diagram showing the lower seal structure included in the seal structure shown in Figure 6. Figure 15 is a cross-sectional view along the line XV-XV in Figure 14.

[0066] As shown in Figures 14 and 15, the lower seal structure 50 is provided along the laterally extending lower edge of the opening edge of the opening 21b. The lower edge of the opening edge of the opening 21b corresponds to the front end of the front inclined plate 214. The lower seal structure 50 includes a plurality of cylinders 51, a plurality of guide members 52, a plurality of brackets 53, a plurality of brushes 54, and an elastic member 55.

[0067] In this embodiment, the lower seal structure 50 includes three cylinders 51. The three cylinders 51 are mounted on the outer surface of the inclined plate 214 and are arranged laterally. The lower seal structure 50 includes the same number of guide members 52 as the cylinders 51. A guide member 52 is provided for each cylinder 51 and is arranged laterally alongside the corresponding cylinder 51. Each cylinder 51 is configured to have a piston rod that can move back and forth in the front-rear direction. Each guide member 52 is configured to have a guide rod that can move back and forth in the front-rear direction. A single bracket 53 is commonly attached to the tip of the piston rod of the cylinder 51 and the tip of the guide rod of the guide member 52 corresponding to the cylinder 51. As a result, the guide rod of the guide member 52 moves back and forth in conjunction with the movement of the piston rod of the corresponding cylinder 51.

[0068] A single brush 54 is fixed to each bracket 53. In other words, there is a brush 54 for each bracket 53. Specifically, the base end of the brush 54 is fixed to the bracket 53 so as to be rotatable around an axis extending in the direction normal to the outer surface of the inclined plate 214, and the bristles of the brush 54 extend forward from the base end.

[0069] An elastic member 55 is provided at the front end of the inclined plate 214. The elastic member 55 is provided at the front end of the inclined plate 214, extending along the entire length of the inclined plate 214 in the lateral direction. The elastic member 55 is a plate material that protrudes forward from the front end of the inclined plate 214 (to the outer surface Wa of the workpiece W). The elastic member 55 is made of wear-resistant rubber and is flexible. Examples of constituent materials for the elastic member 55 include butadiene rubber, styrene-butadiene rubber, urethane rubber, nitrile rubber, and ethylene propylene rubber. The base end of the elastic member 55 is fixed to the outer surface of the inclined plate 214, and the tip of the elastic member 55 is a free end. The elastic member 55 is provided upstream of the brush 54 in the direction of rotation of the workpiece W. In other words, the brush 54 is located outside the cabinet 21, beyond the elastic member 55.

[0070] Furthermore, the front end of the inclined plate of the receiving member 23 that covers the front inclined plate 214 is also provided with a sealing structure similar to the lower sealing structure 50. A brush is provided at the front end of the side plate of the receiving member 23 that covers the side plate 212 (see Figure 8). The base end of the brush is fixed to the outer surface of the side plate of the receiving member 23. The brush extends inclined toward the side plate 212 as it moves forward from the base end.

[0071] Next, the shot processing method performed by the control device 17 will be explained with reference to Figures 16 to 22. Figure 16 is a flowchart showing the shot processing method performed by the control device shown in Figure 1. Figure 17 is a flowchart showing the attitude control in Figure 16 in detail. Figure 18 is a diagram for explaining the processing range of the workpiece shown in Figure 1. Figure 19 is a diagram for explaining the initial position of the projection device shown in Figure 6. Figure 20 is a diagram for explaining the measurement position of the projection device shown in Figure 6. Figure 21 is a diagram for explaining the tilting of the projection device shown in Figure 6. Figure 22 is a diagram for explaining the target position of the projection device shown in Figure 6.

[0072] The shot blasting method shown in Figure 16 is initiated, for example, when the workpiece W is set in the rotating mechanism 100 and the operator performs the shot blasting start operation. As shown in Figure 18, the outer surface Wa of the workpiece W is divided into multiple processing ranges (in this example, processing ranges R1 to R7) in the lateral direction, according to the range in which the projection device 12 can perform shot blasting.

[0073] As shown in Figure 19, the projection device 12 is moved to an initial position in the front-rear direction relative to the target range among the machining ranges R1 to R7, and the tilt of the projection device 12 is set to the initial tilt. In this example, shot processing is performed sequentially from machining range R1 (first machining range) to machining range R7, so machining range R1 is selected first as the target range. The initial position is a position where the opening 21b is sufficiently far from the outer surface Wa. The initial tilt can be set, for example, by a rotation angle sensor provided on the rotation axis 24. The initial tilt is set to a tilt of the projection device 12 such that the orientation of the opening 21b is perpendicular to the normal direction of the floor surface and the axis AX1. In the following description, the initial position and initial tilt may be collectively referred to as the "initial posture".

[0074] First, the control device 17 instructs the rotating mechanism 100 to start rotating the workpiece W (step S1). Specifically, once the initial setup described above is complete, the control device 17 sends a rotation command to the rotating mechanism 100. When the rotating mechanism 100 receives the rotation command from the control device 17, it rotates the turning roll 102, thereby rotating the workpiece W. The rotating mechanism 100 then sends a response to the control device 17 indicating that it has started rotating.

[0075] Next, when the control device 17 receives the above response from the rotation mechanism 100, it performs attitude control (step S2). As shown in Figure 17, in attitude control, first the control device 17 moves the projection device 12 to the measurement position (step S21). As shown in Figure 20, the measurement position is the position where the distance to the outer surface Wa is measured, and is located a predetermined distance (measurement distance) away from the outer surface Wa. The measurement distance is set within a range in which the projection device 12 does not interfere with any workpiece W of any diameter. The control device 17 moves the projection device 12 from the initial position to the measurement position by controlling the movement mechanism 15. During the movement from the initial position to the measurement position, the distance sensors 26a to 26d measure the distance and transmit the measured value to the control device 17.

[0076] Next, the control device 17 determines the sensor set to be used for attitude control (step S22). For example, the control device 17 determines the sensor set to be used for attitude control to include the distance sensor that measured the distance earliest among the distance sensors 26a to 26d. For example, if the workpiece W has a tapered shape, the sensor set on the larger diameter side is used. Here, we will explain assuming that the sensor set of distance sensor 26a and distance sensor 26b is used for attitude control.

[0077] Next, the control device 17 tilts the projection device 12 (step S23). In step S23, as shown in Figure 21, the control device 17 controls the tilting mechanism 16 to tilt the projection device 12 so that the difference (absolute value of the difference) between the distance L1 (first distance) measured by the distance sensor 26a and the distance L2 (second distance) measured by the distance sensor 26b becomes smaller than the tilt threshold. The tilt threshold is set in advance. For example, the tilt threshold is 5 mm.

[0078] Next, the control device 17 moves the projection device 12 to the target position (step S24). As shown in Figure 22, the target position is the position where the projection device 12 performs projection, and is a predetermined distance (target distance) away from the outer surface Wa. The target distance is set to the distance at which shot leakage is minimized while the cabinet 21 does not come into contact with the outer surface Wa. The control device 17 moves the projection device 12 forward by controlling the movement mechanism 15 until the distance L1 or distance L2 becomes the target distance.

[0079] Next, the control device 17 determines whether the attitude conditions are met (step S25). The attitude conditions are that the difference between distance L1 and distance L2 is smaller than the tilt threshold, and that distances L1 and L2 are included within the target range. The target range is the range that includes the target distance. The lower limit of the target range is, for example, the value obtained by subtracting the distance threshold from the target distance, and the upper limit of the target range is, for example, the value obtained by adding the distance threshold to the target distance. The distance threshold is set in advance. The distance threshold is, for example, 5 mm. For example, in step S24, when the projection device 12 moves forward from the measurement position toward the target position, the difference between distance L1 and distance L2 may increase due to factors such as a change in the position of the outer surface Wa measured by the distance sensors 26a and 26b. In such a case, the attitude conditions are not met.

[0080] If it is determined in step S25 that the attitude conditions are not met (step S25: NO), the control device 17 repeats steps S23 to S25. On the other hand, if it is determined in step S25 that the attitude conditions are met (step S25: YES), the control device 17 terminates attitude control.

[0081] As described above, the control device 17 performs attitude control using either a first sensor set of distance sensors 26a and 26b or a second sensor set of distance sensors 26c and 26d. When using the first sensor set, the control device 17 performs attitude control based on distances L1 and L2. Specifically, the control device 17 controls the movement mechanism 15 and the tilting mechanism 16 to tilt the projection device 12 so that the difference between distances L1 and L2 becomes smaller than the tilt threshold, and also moves the projection device 12 in the forward and backward directions so that distances L1 and L2 fall within the target range.

[0082] When using the second sensor set, the control device 17 performs attitude control based on the distance L3 measured by the distance sensor 26c and the distance L4 measured by the distance sensor 26d. Specifically, the control device 17 controls the movement mechanism 15 and the tilting mechanism 16 to tilt the projection device 12 so that the difference between distance L3 and distance L4 becomes smaller than the tilt threshold, and also moves the projection device 12 in the forward and backward directions so that distances L3 and L4 fall within the target range.

[0083] Next, the control device 17 presses the seal structure 25 against the outer surface Wa (step S3). In step S3, the control device 17 controls each cylinder 31 to advance the cylinder rod until the tip of the elastic member 36 contacts the outer surface Wa. The control device 17 controls the cylinder 41 to advance the cylinder rod until the pair of rollers 47 contact the outer surface Wa. Similarly, the control device 17 controls each cylinder 51 to advance the cylinder rod until the tip of the brush 54 contacts the outer surface Wa. The advancement of the cylinder rod is stopped when the pressure received by the cylinder rod reaches the set pressure.

[0084] In other words, each cylinder 31 presses the elastic member 36 against the outer surface Wa of the workpiece W after the orientation of the projection device 12 (cabinet 21) relative to the outer surface Wa of the workpiece W has been adjusted. Cylinder 41 moves the magnet unit 44 toward the outer surface Wa of the workpiece W after the orientation of the projection device 12 (cabinet 21) relative to the outer surface Wa of the workpiece W has been adjusted. Each cylinder 51 presses the brush 54 against the outer surface Wa of the workpiece W after the orientation of the projection device 12 (cabinet 21) relative to the outer surface Wa of the workpiece W has been adjusted.

[0085] Next, the control device 17 starts projection (step S4). In step S4, the control device 17 causes the projection machine 22 to project the projection material by controlling the drive unit (not shown) of the projection machine 22. The projection amount and projection speed are set in advance. The projection amount and projection speed may be set based on work information about the workpiece W entered by the operator. The workpiece information may be entered from a higher-level tool such as CAD (Computer Aided Design). In the second and subsequent processing ranges, the control device 17 may change the shot processing conditions according to the inspection results by the inspection device 28 in the previous processing range.

[0086] Next, the control device 17 determines whether the stop condition has been met (step S5). The stop condition is a condition for stopping the shot processing on the target area. For example, the stop condition may be that the workpiece W has completed one rotation around the axis AX1. One rotation of the workpiece W is detected, for example, by a rotation angle sensor provided on the rotation mechanism 100. Alternatively, the stop condition may be that the processing of the target area meets the required specifications for shot processing, as determined by the inspection result from the inspection device 28.

[0087] In step S5, if it is determined that the stop condition is not met (step S5: NO), the control device 17 repeats the determination in step S5 until the stop condition is met. During this time, projection continues. On the other hand, if it is determined in step S5 that the stop condition is met (step S5: YES), the control device 17 stops the projection (step S6). In step S4, the control device 17 stops the projector 22 by controlling the drive unit (not shown) of the projector 22.

[0088] Next, the control device 17 releases the pressure on the seal structure 25 (step S7). In step S7, the control device 17 controls each cylinder 31, cylinder 41, and each cylinder 51 to retract the tip of the cylinder rod back to its original position.

[0089] Next, the control device 17 returns the projection device 12 to its initial position (step S8). In step S8, the control device 17 controls the movement mechanism 15 to return the projection device 12 to its initial position and controls the tilting mechanism 16 to return the projection device 12 to its initial tilt.

[0090] Next, the control device 17 determines whether or not the termination condition has been met (step S9). The termination condition is the condition for ending the shot blasting process on the workpiece W. For example, the termination condition may be that the shot blasting process has been completed for all machining ranges R1 to R7.

[0091] If it is determined in step S9 that the termination condition is not met (step S9: NO), the control device 17 controls the movement mechanism 15 to move the projection device 12 laterally (step S10) and selects the next processing range as the target range. For example, by controlling the movement mechanism 15, the control device 17 moves the projection device 12 to the processing range R2 (second processing range) adjacent to processing range R1, in accordance with the completion of shot processing in processing range R1. Then, the control device 17 performs steps S2 to S9 again. On the other hand, if it is determined in step S9 that the termination condition is met (step S9: YES), the shot processing method is terminated.

[0092] In the shot processing apparatus 10 described above, distance sensors 26a and 26b are provided spaced apart from each other in the vertical direction. Therefore, the inclination of the projection device 12 relative to the outer surface Wa of the workpiece W can be estimated from the distance L1 measured by distance sensor 26a and the distance L2 measured by distance sensor 26b. Consequently, by controlling the attitude of the projection device 12 based on distances L1 and L2, the projectile can be projected onto the outer surface Wa of the workpiece W at a desired angle of incidence, even if the diameter of the workpiece W fluctuates. As a result, it becomes possible to improve machining accuracy.

[0093] Specifically, the orientation of the projection device 12 is controlled so that the difference between distance L1 and distance L2 is smaller than the tilt threshold, and both distances L1 and L2 fall within the target range. The outer surface Wa exposed from the opening 21b of the workpiece W is close to a flat surface. Therefore, by reducing the difference between distance L1 and distance L2, the tilt of the projection device 12 relative to the outer surface Wa of the workpiece W is reduced. If both distances L1 and L2 are within the target range, the desired projection distance can be obtained. Therefore, even if the diameter of the workpiece W fluctuates, the projection material can be projected onto the outer surface Wa of the workpiece W at the desired incidence angle and projection distance. As a result, it becomes possible to improve machining accuracy.

[0094] In the shot processing apparatus 10, distance sensors 26c and 26d are provided spaced laterally apart from distance sensors 26a and 26b. The control device 17 moves the projection device 12 from its initial position toward the outer surface Wa of the workpiece W by controlling the movement mechanism 15, and performs attitude control using the sensor set that includes the distance sensor that measured the measurement distance first, from the first sensor set of distance sensors 26a and 26b and the second sensor set of distance sensors 26c and 26d. For example, when processing a tapered workpiece W, the diameter of the workpiece W differs depending on the position along the axis AX1 of the workpiece W. Therefore, if the sensor set on the smaller diameter side is used, the projection device 12 may approach the outer surface Wa and come into contact with the outer surface Wa. With the above configuration, the sensor set on the larger diameter side of the first sensor set and the second sensor set is used, so it is possible to avoid the projection device 12 coming into contact with the outer surface Wa of the workpiece W.

[0095] Even when the second sensor set is used, the inclination of the projection device 12 relative to the outer surface Wa of the workpiece W can be estimated using the distance L3 measured by the distance sensor 26c and the distance L4 measured by the distance sensor 26d, similar to the first sensor set. Therefore, by controlling the attitude of the projection device 12 based on the distances L3 and L4, the projection material can be projected onto the outer surface Wa of the workpiece W at a desired angle of incidence, even if the diameter of the workpiece W fluctuates. As a result, it becomes possible to improve machining accuracy.

[0096] Specifically, the attitude of the projection device 12 is controlled so that the difference between distance L3 and distance L4 is smaller than the tilt threshold, and both distances L3 and L4 fall within the target range. By reducing the difference between distance L3 and distance L4, the tilt of the projection device 12 relative to the outer surface Wa of the workpiece W is reduced. If both distances L3 and L4 are within the target range, the desired projection distance can be obtained. Therefore, even if the diameter of the workpiece W fluctuates, the projection material can be projected onto the outer surface Wa of the workpiece W at the desired incidence angle and projection distance. As a result, it becomes possible to improve machining accuracy.

[0097] The longer the distance between each distance sensor and the outer surface Wa, the greater the error in the measured value. In attitude control, the error in the measured value of each distance sensor can be reduced by moving the projection device 12 from the initial position to the measurement position.

[0098] Instead of tilting the projection device 12, it is also conceivable to move the projection device 12 up and down. However, tilting the projection device 12 requires less driving force compared to moving it up and down. Therefore, the shot processing device 10 can be miniaturized. If the projection device 12 is moved up and down, the center of gravity of the shot processing device 10 will change, which may cause the shot processing device 10 to tip over. In contrast, even if the projection device 12 is tilted, the change in the center of gravity of the shot processing device 10 is suppressed, thus reducing the possibility of the shot processing device 10 tipping over.

[0099] In the shot processing device 10, shot processing is performed for each processing area that the projection device 12 can process. Therefore, there is no need to prepare a cabinet to house the entire workpiece W, and the shot processing system 1 (shot processing device 10) can be made smaller. Even with a long workpiece W, the outer surface Wa can be processed along the entire length of the workpiece W.

[0100] For example, when machining a tapered workpiece W, the diameter of the workpiece W varies depending on its position along the axis AX1 of the workpiece W. Therefore, if the abrasive material is projected onto a certain machining range at an angle set in another machining range with a different diameter, the desired angle of incidence may not be obtained. In response to this, the control device 17 performs attitude control for each of the multiple machining ranges. Therefore, even with a tapered workpiece W, the abrasive material can be projected onto the outer surface Wa of the workpiece W at the desired angle of incidence. As a result, machining accuracy can be improved.

[0101] The control device 17 may control the moving mechanism 15 based on work information indicating the shape of the workpiece W. For example, the control device 17 obtains the length along the axis AX1 of the workpiece W from the work information and sets the machining range according to that length. In this way, even if the workpiece W has a different shape, the projection device 12 can be moved according to the shape of the workpiece W.

[0102] By reducing the size of the opening 21b, the area over which the projectile material leaks is reduced, and the seal structure 25 can be miniaturized. Furthermore, the amount of variation in the curvature of the outer surface Wa exposed from the opening 21b is suppressed. This improves the sealing performance.

[0103] The control device 17 may change the shot processing conditions according to the inspection results from the inspection device 28. In other words, feedback control may be performed according to the processing state of the outer surface Wa of the workpiece W. In this case, it becomes possible to improve the processing accuracy of the outer surface Wa.

[0104] If foreign matter is present on the outer surface Wa, the foreign matter may collide with (interfere with) the projection device 12, potentially damaging the projection device 12. In contrast, in the shot processing device 10, when foreign matter is detected, the rotation mechanism 100 is stopped, and the shot processing device 10 is also stopped. With this configuration, interference between the foreign matter and the projection device 12 can be avoided, and damage to the projection device 12 (shot processing device 10) can be avoided.

[0105] In the shot processing apparatus 10, a magnet unit 44 is provided along the vertically extending side edge of the opening edge 21b of the cabinet 21. With this configuration, even if a gap 48 is created between the magnet unit 44 and the outer surface Wa of the workpiece W, the abrasive material is attracted to the magnet unit 44 in the gap 48, and the abrasive material accumulates on the surface of the magnet unit 44. As a result, the gap 48 is sealed by the abrasive material, and the possibility of powder and granular material containing the abrasive material leaking out of the gap 48 to the outside of the projection chamber 21a is reduced. As a result, leakage of powder and granular material can be suppressed.

[0106] The brush 46 is positioned outside the cabinet 21, beyond the magnet unit 44. The bristles of the brush 46 form a labyrinth structure, so even if powder passes through the gap 48, the brush 46 reduces the possibility of the powder leaking outside the projection chamber 21a. As a result, leakage of powder can be further suppressed. Even if powder does pass through the brush 46, the side seal structure 40 slows its speed, thus narrowing the scattering range of the powder.

[0107] The brush 46 is inclined toward the front of the magnet unit 44. This makes it easier for the abrasive material that seals the gap 48 to remain inside the gap 48 due to the tip of the brush 46. For example, even if the abrasive material enters the gap 48 from the projection chamber 21a at high speed, the possibility of the abrasive layer collapsing is reduced. Therefore, the possibility of the powder and granular material containing the abrasive material leaking out of the gap 48 to the outside of the projection chamber 21a is reduced. As a result, it becomes possible to suppress the leakage of the powder and granular material.

[0108] Between two adjacent magnets 44a, a gap 44c is formed where no magnet 44a is provided, making it difficult for projectile material to accumulate in the gap 44c. In the shot processing device 10, a magnet 44b is provided in a position that overlaps with the gap 44c in the lateral direction. Therefore, projectile material that has passed through the gap 44c is attracted to the magnet 44b in the gap between the magnet 44b and the outer surface Wa, and accumulates on the surface of the magnet 44b. This seals the gap between the magnet 44b and the outer surface Wa. As a result, leakage of powder and granular material can be further suppressed.

[0109] The position of the magnet unit 44 relative to the outer surface Wa of the workpiece W is determined by the two rollers 47. With this configuration, the distance Dm between the magnet unit 44 and the outer surface Wa is set, and a gap 48 is formed. By setting the distance Dm to the distance over which the magnetic force of the magnet unit 44 extends, the gap 48 can be more reliably sealed by the abrasive material. As a result, leakage of powder and granular material can be further suppressed. Even if the shape of the gap 48 changes due to differences in the shape (diameter) of the workpiece W, the gap 48 can still be sealed by the abrasive material.

[0110] In a configuration that prevents leakage of powder or granular material by contacting an elastic member with the outer surface Wa, the elastic member wears down due to the rotation of the workpiece W. In contrast, in the side seal structure 40, the magnet unit 44 does not come into contact with the outer surface Wa, and the gap 48 is filled with the projectile material, thus eliminating the need to replace the magnet unit 44 due to wear.

[0111] After adjusting the orientation of the projection device 12 (cabinet 21) relative to the outer surface Wa of the workpiece W, the magnet unit 44 is moved toward the outer surface Wa. This configuration reduces variations in distance Dm. Therefore, the gap 48 can be more reliably sealed by the projection material. As a result, leakage of powder and granular material can be further suppressed.

[0112] In the shot processing apparatus 10, an elastic member 36 is provided along the upper, laterally extending edge of the opening 21b of the cabinet 21. The elastic member 36 is moved forward and backward relative to the outer surface Wa of the workpiece W by a plurality of cylinders 31 arranged laterally. With this configuration, even if the workpiece W to be processed is tapered, the elastic member 36 is pressed against the outer surface Wa by adjusting the forward and backward movement of the elastic member 36 by each cylinder 31. Therefore, the gap between the elastic member 36 and the outer surface Wa can be reduced. As a result, leakage of powder and granular material can be suppressed.

[0113] The elastic member 36 is bent into a convex U-shape toward the outer surface Wa of the workpiece W. With this configuration, a cavity is formed inside the U-shape of the elastic member 36. Therefore, when the elastic member 36 is pressed against the outer surface Wa of the workpiece W, the U-shaped tip of the elastic member 36 is pushed toward the cavity and deforms to conform to the shape of the outer surface Wa. Due to the flexible deformation characteristics and repulsive force (restoring force) of the elastic member 36, the elastic member 36 can adhere closely to the outer surface Wa, making it possible to further suppress leakage of powder and granular material.

[0114] The brush 34 is positioned outside the cabinet 21, beyond the elastic member 36. The bristles of the brush 34 form a labyrinth structure, so even if granular material passes through the gap between the elastic member 36 and the outer surface Wa, the brush 34 reduces the possibility of the granular material leaking outside the projection chamber 21a. As a result, leakage of granular material can be further suppressed.

[0115] Since the brushes 34 are less prone to deformation than the elastic member 36, if multiple brushes 34 are integrated, the brushes may hinder the adjustment of the reciprocating movement of the elastic member 36. In contrast, in the upper seal structure 30, each brush 34 is moved back and forth relative to the outer surface Wa by the corresponding cylinder 31. Therefore, the possibility of the adjustment of the reciprocating movement of the elastic member 36 being hindered can be reduced. Consequently, the gap between the elastic member 36 and the outer surface Wa can be further reduced, making it possible to further suppress leakage of powder and granular material.

[0116] When the tip of each brush 34 comes into contact with the outer surface Wa, the brush 34 rotates along the outer surface Wa. This allows each brush 34 to make close contact with the outer surface Wa. Therefore, even if granular material passes through the gap between the elastic member 36 and the outer surface Wa, the possibility of the granular material leaking out of the projection chamber 21a is further reduced by the brushes 34. As a result, leakage of granular material can be further suppressed.

[0117] If the elastic body 35 is not provided, the shape of the brush 34 may be distorted by the rotation of the workpiece W, resulting in large gaps in the brush 34. In contrast, in the upper seal structure 30, the elastic body 35 is provided outside the cabinet 21, beyond the brush 34. With this configuration, the shape of the brush 34 is maintained by the elastic body 35. Therefore, the possibility of large gaps forming in the brush 34 can be reduced. Consequently, leakage of powder and granular material can be further suppressed.

[0118] After adjusting the orientation of the projection device 12 (cabinet 21) relative to the outer surface Wa of the workpiece W, the elastic member 36 is pressed against the outer surface Wa. With this configuration, the gap between the elastic member 36 and the outer surface Wa can be further reduced. As a result, leakage of powder and granular material can be further suppressed.

[0119] The shot processing apparatus relating to this disclosure is not limited to the embodiments described above.

[0120] For example, the moving mechanism 15 only needs to be capable of moving the projection device 12 relative to the workpiece W in the front-rear and lateral directions. Instead of moving the supply device 11, projection device 12, recovery device 13, classification device 14, and tilting mechanism 16, the moving mechanism 15 may move the rotating mechanism 100 (workpiece W).

[0121] The lateral length of the opening 21b may be greater than or equal to the length along the axis AX1 of the workpiece W. In this case, the moving mechanism 15 does not need to move the projection device 12 relative to it in the lateral direction.

[0122] The projection device 12 does not necessarily have to include either the first sensor set of distance sensors 26a and 26b or the second sensor set of distance sensors 26c and 26d.

[0123] The projection device 12 does not necessarily include a foreign object detection device 27. The projection device 12 does not necessarily include an inspection device 28.

[0124] The workpiece information may include information such as the projection position, the outer diameter of the workpiece W at the projection position, the total length of the workpiece W, and the angle of incidence of the projection material projected onto the outer surface Wa. The control device 17 may set the target position so that the angle of incidence of the projection material projected from the projection machine 22 onto the outer surface Wa is the angle of incidence included in the workpiece information.

[0125] The control device 17 may change the amount of abrasive material supplied based on the measurements of the distance sensors 26a to 26d. For example, the control device 17 may increase the amount of abrasive material supplied when the distance L1 to L4 is long, and decrease the amount of abrasive material supplied when the distance L1 to L4 is short. This makes it possible to ensure uniformity of the finished product and avoid over-quality or under-quality results.

[0126] The control device 17 does not necessarily have to perform tilt control; it may adjust the tilt of the projection device 12 by pressing the opening 21b against the outer surface Wa. In this case, the projection device 12 does not need to include distance sensors 26a to 26d.

[0127] Each seal structure does not need to include a guide member, as long as the cylinder rod can be moved forward and backward.

[0128] The upper seal structure 30 does not necessarily include the elastic body 35. Even in this case, the possibility of powder material leaking to the outside of the projection chamber 21a by the brush 34 is reduced. The upper seal structure 30 does not necessarily include the brush 34. Even in this case, the possibility of powder material leaking to the outside of the projection chamber 21a by the elastic member 36 is reduced.

[0129] Multiple brushes 34 may be integrated to form a single brush.

[0130] The side seal structure 40 does not necessarily include a liner 45. The side seal structure 40 does not necessarily include a brush 46. In this case as well, the possibility of powder material leaking to the outside of the projection chamber 21a by the magnet unit 44 is reduced.

[0131] For example, a desired gap 48 may be obtained by attitude control. In this case, the side seal structure 40 does not need to include the cylinder 41, guide member 42, and roller 47.

[0132] The lower seal structure 50 may have the same configuration as the side seal structure 40. That is, the lower seal structure 50 may include a magnet unit and fill the gap between the magnet unit and the outer surface Wa with a projection material.

[0133] The side seal structure 40 may have the same configuration as the upper seal structure 30. That is, the side seal structure 40 may include an elastic member and a plurality of cylinders that press the elastic member against the outer surface Wa.

[0134] Attitude control is not limited to the attitude control of the above embodiment. For example, the projection device 12 may include four limit switches provided at the four corners of the opening 21b instead of or in addition to the distance sensors 26a to 26d, and the control device 17 may perform attitude control using these limit switches.

[0135] To explain in more detail, the control device 17 first controls the movement mechanism 15 to move the projection device 12 forward until the upper limit switch switches from the off state to the on state. Then, the control device 17 controls the tilting mechanism 16 to tilt the projection device 12 until the lower limit switch switches from the off state to the on state. At this time, the control device 17 measures the time from the moment the upper limit switch switches from the on state to the off state to the moment the lower limit switch switches from the off state to the on state using a timer (not shown).

[0136] Then, the control device 17 controls the tilting mechanism 16 to return the tilt of the projection device 12 to its original position for half the measured time. As a result, the upper and lower limit switches are turned off, and the control device 17 controls the movement mechanism 15 to move the projection device 12 forward. When both the upper and lower limit switches are switched on, the opening 21b is considered to be aligned with the outer surface Wa, and the control device 17 terminates attitude control. On the other hand, if neither of the upper or lower limit switches is switched on, the control device 17 repeats the above series of processes until both the upper and lower limit switches are switched on.

[0137] The projection device 12 may include, in place of or in addition to, distance sensors 26a to 26d, distance sensors provided on the upper part of the cabinet 21, distance sensors provided on the middle part of the cabinet 21, and distance sensors provided on the lower part of the cabinet 21, and the control device 17 may perform attitude control using the distances measured by these distance sensors. Each distance sensor measures the distance to the outer surface Wa through the opening 21b.

[0138] Specifically, the control device 17 calculates the radius of the workpiece W by deriving a curve by connecting the distances measured by these distance sensors. Then, the control device 17 controls the tilting mechanism 16 to tilt the projection device 12 to an angle along the calculated radius. Finally, the control device 17 controls the moving mechanism 15 to move the projection device 12 forward to the target position and terminates attitude control.

[0139] This disclosure includes the forms described in the following clauses.

[0140] [Clause 1] A shot blasting apparatus for blasting the outer surface of a cylindrical workpiece, A cabinet defining a projection chamber, the cabinet having an opening that communicates with the projection chamber and opens toward the outer surface of the workpiece, A projection machine provided in the cabinet for projecting a projection material toward the outer surface of the workpiece through the opening, A sealing structure provided along the opening edge of the aforementioned opening, Equipped with, The aforementioned sealing structure is An elastic member provided on the portion of the opening edge that extends in a first direction along the central axis of the workpiece, A plurality of drive units arranged in the first direction, each of which moves the elastic member forward and backward relative to the outer surface of the workpiece, A shot processing device, including a shot processing device.

[0141] [Clause 2] The shot processing apparatus according to Clause 1, wherein the elastic member is a plate material bent into a convex U-shape toward the outer surface of the workpiece.

[0142] [Clause 3] The shot apparatus according to Clause 1 or Clause 2, wherein the sealing structure further includes a brush located outside the cabinet beyond the elastic member.

[0143] [Clause 4] The brush is divided into a plurality of brush sections in the first direction, The shot processing apparatus according to Clause 3, wherein the plurality of brush portions are each moved forward and backward relative to the outer surface of the workpiece by the plurality of drive units.

[0144] [Clause 5] The shot processing apparatus according to Clause 4, wherein each of the plurality of brush portions is provided so as to be rotatable about an axis intersecting the first direction and the direction in which the brush portion moves forward and backward.

[0145] [Clause 6] The shot apparatus according to any one of Clauses 3 to 5, wherein the sealing structure further includes an elastic body located outside the cabinet beyond the brush.

[0146] [Clause 7] The shot processing apparatus according to any one of Clauses 1 to 6, wherein the plurality of drive units press the elastic member against the outer surface of the workpiece after the orientation of the cabinet with respect to the outer surface of the workpiece has been adjusted.

[0147] In the shot processing apparatus described in Clause 1, an elastic member is provided on the portion of the opening edge of the cabinet opening that extends in a first direction along the central axis of the workpiece. The elastic member is moved back and forth relative to the outer surface of the workpiece by a plurality of drive units arranged in the first direction. Therefore, even if the workpiece to be processed is tapered, the elastic member is pressed against the outer surface of the workpiece by adjusting the movement of the elastic member by each drive unit. Consequently, the gap between the elastic member and the outer surface of the workpiece can be reduced. As a result, leakage of powder and granular material can be suppressed.

[0148] In the shot processing apparatus described in Clause 2, the elastic member is bent into a convex U-shape toward the outer surface of the workpiece. With this configuration, a cavity is formed inside the U-shape of the elastic member. Therefore, when the elastic member is pressed against the outer surface of the workpiece, the U-shaped tip of the elastic member is pushed toward the cavity and deforms into a shape that conforms to the outer surface. Due to the flexible deformation characteristics and repulsive force (restoring force) of the elastic member, the elastic member can adhere closely to the outer surface, making it possible to further suppress leakage of powder and granular material.

[0149] In the shot processing apparatus described in Clause 3, a labyrinth structure is formed by the bristles of the brush. Therefore, even if granular material passes through the gap between the elastic member and the outer surface of the workpiece, the brush reduces the possibility of the granular material leaking out of the projection chamber. As a result, leakage of granular material can be further suppressed.

[0150] In the shot processing apparatus described in Clause 4, each brush section is moved forward and backward relative to the outer surface of the workpiece by a corresponding drive unit. This reduces the possibility of interference with the adjustment of the movement of the elastic member. Consequently, the gap between the elastic member and the outer surface of the workpiece can be further reduced, and leakage of powder and granular material can be further suppressed.

[0151] In the shot processing apparatus described in Clause 5, when the tip of each brush portion contacts the outer surface of the workpiece, the brush portion rotates so as to follow the outer surface. This allows each brush portion to adhere closely to the outer surface of the workpiece. Therefore, leakage of powder and granular material can be further suppressed.

[0152] In the shot processing apparatus described in Clause 6, the shape of the brush is maintained by an elastic body. This reduces the possibility of large gaps forming in the brush. Therefore, it is possible to further suppress leakage of powder and granular material.

[0153] In the shot processing apparatus described in Clause 7, the cabinet's orientation relative to the outer surface of the workpiece is adjusted, and then the elastic member is pressed against the outer surface of the workpiece. This configuration further reduces the gap between the elastic member and the outer surface of the workpiece. As a result, leakage of powder and granular material can be further suppressed. [Explanation of Symbols]

[0154] 10...Shot processing device, 12...Projection device, 15...Moving mechanism, 16...Tilting mechanism, 17...Control device, 21...Cabinet, 21a...Projection chamber, 21b...Opening, 22...Projector, 23...Receiving member, 24...Rotation shaft, 25...Seal structure, 26a...Distance sensor (1st distance sensor), 26b...Distance sensor (2nd distance sensor), 26c...Distance sensor (3rd distance sensor), 26d...Distance sensor (4th distance sensor), 27...Foreign object detection device, 28...Inspection device, 30...Upper seal structure 31...Cylinder (drive unit), 34...Brush (brush part), 35...Elastic body, 36...Elastic member, 40...Side seal structure, 41...Cylinder (drive unit), 44...Magnet unit, 44a...Magnet (first magnet), 44b...Magnet (second magnet), 44c...Missing part, 44d...Missing part, 46...Brush, 47...Roller (positioning member), AX1...Axis (center axis), AX2...Axis, R1...Machining range (first machining range), R2...Machining range (second machining range), W...Workpiece, Wa...Outer surface.

Claims

1. A shot blasting apparatus for blasting the outer surface of a cylindrical workpiece, A cabinet defining a projection chamber, the cabinet having an opening that communicates with the projection chamber and opens toward the outer surface of the workpiece, A projection machine provided in the cabinet for projecting a projection material toward the outer surface of the workpiece through the opening, A sealing structure provided along the opening edge of the aforementioned opening, Equipped with, The aforementioned sealing structure is An elastic member is provided on the portion of the opening edge that extends in a first direction along the central axis of the workpiece, A plurality of drive units arranged in the first direction, each of which moves the elastic member forward and backward relative to the outer surface of the workpiece, A shot processing device, including a shot processing device.

2. The shot processing apparatus according to claim 1, wherein the elastic member is a plate material bent into a convex U-shape toward the outer surface of the workpiece.

3. The shot processing apparatus according to claim 1 or 2, wherein the sealing structure further includes a brush located outside the cabinet beyond the elastic member.

4. The brush is divided into a plurality of brush sections in the first direction, The shot processing apparatus according to claim 3, wherein the plurality of brush portions are each moved forward and backward relative to the outer surface of the workpiece by the plurality of drive units.

5. The shot processing apparatus according to claim 4, wherein each of the plurality of brush portions is provided so as to be rotatable about an axis intersecting the first direction and the direction in which the brush portion moves forward and backward.

6. The shot processing apparatus according to claim 3, wherein the sealing structure further includes an elastic body located outside the cabinet beyond the brush.

7. The shot processing apparatus according to claim 1 or 2, wherein the plurality of drive units press the elastic member against the outer surface of the workpiece after the orientation of the cabinet with respect to the outer surface of the workpiece has been adjusted.

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