Non-contact support device

Abstract

To provide a non-contact support device which can increase a force for lifting a workpiece.SOLUTION: A non-contact support device 10 includes a main body 20 and a sub-body 40. A workpiece support part 21 forming an annular shape is formed at a first end in an axial direction of the main body 20. In a portion, which is located at the radial inner side relative to the workpiece support part 21, of the main body 20, an inner recessed part 22 recessed to the second end side in the axial direction is formed. In each body 20, 40, an axial passage 51 which is supplied with a gas, a radial passage 52 which extends toward the radial outer side and is open at the inner recessed part 22, and a corner passage 80 connecting a downstream side end of the axial passage 51 with an upstream end of the radial passage 52 are formed. A passage area of a corner passage 80 gradually becomes smaller from the axial passage 51 side to the radial passage 52 side.SELECTED DRAWING: Figure 3

Description

Technical Field

[0001] The present disclosure relates to a non-contact support device.

Background Art

[0002] Conventionally, as described in Patent Document 1, a non-contact support device that supports a workpiece in a non-contact manner by using negative pressure generated by an air flow is known. Specifically, when the non-contact support device is brought closer to the workpiece while ejecting air from the non-contact support device to the workpiece, air flows at high speed between the non-contact support device and the workpiece. As a result, a negative pressure state is created between the non-contact support device and the workpiece, and a lifting force acts on the workpiece. As a result, the workpiece is supported by the non-contact support device in a non-contact state.

Prior Art Documents

Patent Documents

[0003]

Patent Document 1

Summary of the Invention

Problems to be Solved by the Invention

[0004] There is still room for improvement in the technology for increasing the lifting force of the workpiece.

Means for Solving the Problems

[0005] The main object of the present disclosure is to provide a non-contact support device capable of increasing the lifting force of a workpiece.

[0006] The present disclosure provides a non-contact support device that supports a workpiece in a non-contact state by ejecting a gas onto the workpiece, comprising a body extending in an axial direction in which a central axis extends and a radial direction orthogonal to the axial direction, At a first end portion of the body in the axial direction, a work support portion is formed which is annular about the central axis and faces the work. In an inner portion of the body in the radial direction relative to the work support portion, an inner concave portion is formed which is recessed toward a second end portion side of the body in the axial direction with respect to the work support portion. In the body, an axial passage extending in the axial direction and supplied with gas, and a radial passage extending toward the outside in the radial direction and opening into the inner concave portion, and a corner passage connecting a downstream end portion of the axial passage and an upstream end portion of the radial passage, are formed side by side in the circumferential direction of the body, and a passage area of the corner passage gradually decreases from the axial passage side toward the radial passage side.

[0007] In the present disclosure, air supplied to the axial passage flows through the corner passage and the radial passage and jets out from the radial passage into the inner concave portion. When the work support portion of the body is brought close to the work in a state where air is jetted out, air flows at high speed between the work support portion and the work. Thereby, the work is supported in a non-contact state by the non-contact support device.

[0008] In the present disclosure, the passage area of the corner passage gradually decreases from the axial passage side toward the radial passage side. Thereby, while smoothing the flow of air, the air can be accelerated. As a result, while increasing the air flow rate jetted into the inner concave portion with respect to the same air supply pressure to the axial passage, the flow velocity of the air jetted into the inner concave portion can be increased. Thereby, the pressure between the inner concave portion and the work can be further reduced, and the lift force of the work can be increased.

Brief Description of the Drawings

[0009]

Figure 1

Figure 2

Figure 3

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Figure 12

Mode for Carrying Out the Invention

[0010] Hereinafter, an embodiment in which the non-contact support device according to the present disclosure is embodied will be described with reference to the drawings. The non-contact support device 10 of the present embodiment is a Bernoulli type non-contact support device.

[0011] As shown in FIGS. 1 to 4, the non-contact support device 10 includes a main body 20 and a sub-body 40. Hereinafter, the direction in which the central axis K of each of the bodies 20 and 40 extends is defined as the axial direction, the direction that extends radially from the center of the central axis K and is orthogonal to the axial direction is defined as the radial direction, and the direction that extends circumferentially around the central axis K is defined as the circumferential direction.

[0012] By combining the main body 20 and the sub-body 40, the flow path of the gas (e.g., compressed gas) supplied from a gas supply device (e.g., a pump) has a structure formed in the main body 20 and the sub-body 40. In this embodiment, the gas is air.

[0013] The main body 20 has a flat cylindrical outer shape. In the main body 20, a work support portion 21 is formed on the outer peripheral portion on the first end portion (lower end portion) side in the axial direction of the non-contact support device 10. The work support portion 21 has a flat surface 21a and has an annular shape centered on the central axis K. The two-dot chain line in FIG. 3 indicates the work W facing the work support portion 21.

[0014] As shown in FIGS. 3 and 4, an inner concave portion 22 that is recessed toward the second end portion (upper end portion) side in the axial direction of the non-contact support device 10 with respect to the work support portion 21 is formed in the inner portion in the radial direction of the main body 20 relative to the work support portion 21. The inner concave portion 22 has an annular shape centered on the central axis K. A columnar concave portion 30 that is recessed in a columnar shape toward the upper end portion side in the axial direction with respect to the inner concave portion 22 is formed in the portion of the main body 20 adjacent to the inner side of the inner concave portion 22 in the radial direction.

[0015] A flat surface portion 23 and an inclined portion 24 are formed in the inner concave portion 22. The flat surface portion 23 has a flat surface 23a extending in the radial direction, extends radially outward from the corner portion between the inner concave portion 22 and the columnar concave portion 30 (specifically, for example, the inner corner portion 33), and has an annular shape centered on the central axis K. The inclined portion 24 is a portion connecting the flat surface portion 23 and the work support portion 21. The inclined portion 24 has an inclined surface 24a whose radial dimension increases toward the lower end portion side of the non-contact support device 10 in the axial direction. The flat surface 23a of the flat surface portion 23, the inclined surface 24a of the inclined portion 24, and the opposing surface (flat surface 21a) of the work support portion 21 with respect to the work W are smoothly continuous.

[0016] As shown in FIGS. 1 to 6, the sub-body 40 includes a disk portion 41, a large-diameter cylindrical portion 42, and a small-diameter cylindrical portion 43. The disk portion 41 has a disk shape extending radially outward about the central axis K. The axial dimension t1 of the disk portion 41 is smaller than the axial distance t2 between the work support portion 21 and the flat portion 23.

[0017] The large-diameter cylindrical portion 42 extends axially from the central portion of the disk portion 41 and has an outer shape of a cylinder. The radial dimension of the large-diameter cylindrical portion 42 is smaller than the radial dimension of the disk portion 41. The small-diameter cylindrical portion 43 extends axially from the central portion of the large-diameter cylindrical portion 42 and has an outer shape of a cylinder. The radial dimension of the small-diameter cylindrical portion 43 is smaller than the radial dimension of the large-diameter cylindrical portion 42.

[0018] As shown in FIGS. 3 and 5, on the outer peripheral portion of the large-diameter cylindrical portion 42, an axial groove portion 44 is formed that extends axially from the end on the small-diameter cylindrical portion 43 side in the axial direction to the disk portion 41 in the axial direction. In the disk portion 41, a radial groove portion 45 is formed that extends radially from the axial groove portion 44 to the radial end of the disk portion 41. As shown in FIGS. 3 and 6, the inner peripheral surfaces of the axial groove portion 44 and the radial groove portion 45 each have an arc shape. The axial groove portion 44 and the radial groove portion 45 are formed in a plurality (12 are illustrated in the figure) and are arranged at equal intervals in the circumferential direction.

[0019] As shown in FIGS. 3 and 4, in the portion of the main body 20 that is adjacent to the inside of the inner concave portion 22 in the radial direction, a columnar concave portion 30 is formed that extends axially about the central axis K. The columnar concave portion 30 is a portion that is recessed in a columnar shape on the upper end portion side of the main body 20 in the axial direction with respect to the inner concave portion 22. The columnar concave portion 30 includes a bottom portion 31 having a flat surface 31a and an inner peripheral surface 32 that extends in the circumferential direction about the central axis K.

[0020] The axial end face of the small-diameter cylindrical portion 43 abuts against the flat surface 31a of the bottom portion 31 of the columnar concave portion 30, and the outer peripheral surface 42a of the large-diameter cylindrical portion 42 abuts against the inner peripheral surface 32 (first inner peripheral surface 32a) of the columnar concave portion 30. The space surrounded by the first inner peripheral surface 32a of the columnar concave portion 30, the outer peripheral surface 43a of the small-diameter cylindrical portion 43, and the large-diameter cylindrical portion 42 is an annular passage portion 50 having an annular shape centered on the central axis K.

[0021] As shown in FIG. 2, a supply hole 64 extending in the axial direction and penetrating to the annular passage portion 50 is formed in the upper end portion of the main body 20. Air is supplied to the supply hole 64 from a gas supply device (not shown). An attachment hole 65 for fixing the non-contact support device 10 to the attachment target portion of the non-contact support device 10 is formed in the upper end portion of the main body 20. The attachment hole 65 extends in the axial direction and a plurality (four are illustrated in the figure) are formed. The attachment target portion is, for example, the tip end portion of an arm of an industrial robot.

[0022] Subsequently, with reference to FIGS. 1 to 5, a configuration for fixing the sub-body 40 to the main body 20 will be described. A bolt insertion hole 60 penetrating the disk portion 41, the large-diameter cylindrical portion 42, and the small-diameter cylindrical portion 43 in the axial direction is formed in the central portion in the radial direction of the sub-body 40. A seating surface 61 against which the head 71 of the bolt 70 abuts is formed at the peripheral edge portion of the bolt insertion hole 60 on the disk portion 41 side of the sub-body 40.

[0023] A female screw hole 62 into which the male screw of the shaft portion 72 of the bolt 70 is screwed is formed in the central portion in the radial direction of the main body 20.

[0024] An annular seal groove portion 63 is formed on the end face on the upper end portion side of the small-diameter cylindrical portion 43. The seal groove portion 63 is formed over the entire circumference of the peripheral edge portion of the bolt insertion hole 60 on the end face. An annular seal member 73 is disposed in the seal groove portion 63. The seal member 73 is formed of an elastic material (for example, a rubber material) and is, for example, an O-ring. The flat surface 31a of the bottom portion 31 constituting the columnar concave portion 30 is a seal surface against which the seal member 73 abuts.

[0025] In a state where the seal member 73 is disposed in the seal groove portion 63, the male thread of the shaft portion 72 of the bolt 70 is screwed into the female thread hole 62. Thereby, while sealing between the main body 20 and the bottom portion 31 of the sub-body 40, the main body 20 and the sub-body 40 are fixed. By the seal, it is possible to suppress the occurrence of a situation where air leaks from the annular passage portion 50 to the bolt insertion hole 60.

[0026] Subsequently, with reference to FIGS. 7 to 9, the gas passages formed by the respective bodies 20 and 40 will be described. FIG. 7 is an enlarged partial view of the vicinity of the corner passage 80 in the cross-sectional view taken along line 3-3 of FIG. 1. The cross-sectional view taken along line 3-3 is a view when the non-contact support device 10 is cut by a plane passing through the central axis K and extending in the axial direction.

[0027] The inner peripheral surface 32 of the columnar recess 30 includes a first inner peripheral surface 32a extending in the axial direction, and a second inner peripheral surface 32b that is continuous with the first inner peripheral surface 32a in the axial direction and is inclined radially outward with respect to the first inner peripheral surface 32a. The radial dimension of the second inner peripheral surface 32b linearly increases toward the lower end side of the non-contact support device 10 in the axial direction.

[0028] The axial passage 51, the corner passage 80, and the radial passage 52 are formed by the respective bodies 20 and 40. The axial passage 51 is a passage that extends from the annular passage portion 50 toward the lower end side of the non-contact support device 10 in the axial direction. The radial passage 52 is a passage that extends radially outward and opens into the inner recess 22. The corner passage 80 is a passage that connects the downstream end of the axial passage 51 and the upstream end of the radial passage 52. The respective passages 51, 80, and 52 are formed side by side at equal intervals in the circumferential direction.

[0029] The second inner peripheral surface 32b and the flat surface 23a of the flat portion 23 are connected by an inner corner portion 33. The inner corner portion 33 has an annular shape extending in the circumferential direction. The inner peripheral surface 33a of the inner corner portion 33 has a curved surface shape that smoothly continues to the inner peripheral surface (second inner peripheral surface 32b) of the axial direction passage 51 and the inner peripheral surface (flat surface 23a) of the radial direction passage 52.

[0030] In FIG. 7, A1 indicates a first boundary line that is the boundary line between the second inner peripheral surface 32b of the columnar recess 30 and the inner peripheral surface 33a of the inner corner portion 33. The first boundary line A1 extends in the circumferential direction. S1 indicates a first virtual surface composed of a set of normal lines to the first boundary line A1. A2 indicates a second boundary line that is the boundary line between the inner peripheral surface 33a of the inner corner portion 33 and the flat surface 23a of the flat portion 23. The second boundary line A2 extends in the circumferential direction. S2 indicates a second virtual surface composed of a set of normal lines to the second boundary line A2.

[0031] Among the passages formed by the axial direction groove portion 44 of the sub-body 40, the columnar recess 30 of the main body 20, and the flat portion 23, the passage on the annular passage portion 50 side with respect to the first virtual surface S1 is the axial direction passage 51. Also, among the passages formed by the axial direction groove portion 44 of the sub-body 40, the columnar recess 30 of the main body 20, and the flat portion 23, the passage on the inner recess 22 side with respect to the second virtual surface S2 is the radial direction passage 52.

[0032] Among the passages formed by the axial direction groove portion 44 of the sub-body 40, the columnar recess 30 of the main body 20, and the flat portion 23, the passage sandwiched between the first virtual surface S1 and the second virtual surface S2 is the corner passage 80.

[0033] The air supplied from the gas supply device to the supply hole 64 flows into the annular passage portion 50. The air that has flowed into the annular passage portion 50 flows into each axial direction passage 51. The air that has flowed into the axial direction passage 51 flows through the corner passage 80 and the radial direction passage 52, and jets out from the radial direction passage 52 into the inner concave portion 22. When the work support portion 21 is brought close to the work W with the air being jetted out, the air flows at high speed between the work support portion 21 and the work W. As a result, the work W is supported in a non-contact state with the work support portion 21.

[0034] Here, as shown in FIG. 8, the passage area of the corner passage 80 gradually decreases from the axial direction passage 51 side toward the radial direction passage 52 side. Thereby, while smoothing the flow of the air, the air can be accelerated. As a result, while increasing the air flow rate jetted into the inner concave portion 22 with respect to the same air supply pressure to the axial direction passage 51, the flow velocity of the air jetted into the inner concave portion 22 can be increased. Thereby, the pressure between the inner concave portion 22 and the work W can be further reduced, and the lift force of the work W can be increased. In other words, the air flow rate for generating the same lift force can be reduced.

[0035] As shown in FIG. 7, the inner peripheral surface 33a of the inner corner portion 33 has a curved surface shape that smoothly continues to the second inner peripheral surface 32b of the columnar concave portion 30 and the flat surface 23a of the flat surface portion 23. That is, the inner peripheral surface 33a forming the inner corner portion 33 has a curved surface shape that smoothly continues to the inner peripheral surface of the axial direction passage 51 and the inner peripheral surface of the radial direction passage 52. Thereby, while making the flow of the air smoother, the air can be further accelerated. As a result, the lift force of the work W can be further increased.

[0036] Incidentally, the inner peripheral surface 33a of the inner corner portion 33 can also be said to have an R chamfered shape. In FIG. 7, a virtual surface P1 obtained by extending the flat surface 23a of the flat portion 23 radially inward and a virtual surface P2 obtained by extending the second inner peripheral surface 32b along the extending direction of the second inner peripheral surface 32b to the lower end side of the non-contact support device 10 are indicated by a one-dot chain line. Among the corners of the columnar recess 30 and the inner recess 22, a part that is radially outside the virtual surface P1 and on the upper end side of the non-contact support device 10 with respect to the virtual surface P2 is formed into an R chamfered shape, whereby the inner peripheral surface 33a is formed into a curved surface shape.

[0037] As shown in FIGS. 7 and 8, the inner peripheral surface 81a forming the outer corner portion 81 of the corner passage 80 has a curved surface shape that smoothly continues to the peripheral surface forming the axial groove portion 44 and the peripheral surface forming the radial groove portion 45. That is, the inner peripheral surface 81a forming the outer corner portion 81 has a curved surface shape that smoothly continues to the inner peripheral surface of the axial passage 51 and the inner peripheral surface of the radial passage 52. Thereby, the air flow in the inner corner portion 33 can be made smooth, and the air can be accelerated more. As a result, the lift force of the work W can be increased more. On the other hand, if the inner corner portion 33 has a corner, the air flow deteriorates, the pressure decreases, and the air flow velocity decreases.

[0038] Incidentally, it is desirable that the radius of curvature R2 of the inner peripheral surface 33a of the inner corner portion 33 is equal to or greater than the radius of curvature R1 of the inner peripheral surface 81a of the outer corner portion 81. Thereby, for example, it becomes easy to realize a passage that gradually reduces the passage area.

[0039] The axial end face of the small-diameter cylindrical portion 43 abuts against the flat surface 31a of the bottom 31 of the columnar concave portion 30, and the outer peripheral surface 42a of the large-diameter cylindrical portion 42 abuts against the second inner peripheral surface 32b of the columnar concave portion 30 over the circumferential direction. Further, the end face of the disk portion 41 abuts against the flat surface 23a of the flat portion 23 over the circumferential direction. Thereby, the sub-body 40 can be stably supported with respect to the main body 20. As a result, displacement of the sub-body 40 with respect to the main body 20 can be suppressed, and occurrence of defects such as internal air leakage can be suppressed. Thereby, the axial passage 51 and the radial passage 52 can function as intended passages at the time of design.

[0040] As shown in FIG. 9, on the opening end side of the radial passage 52, the passage area becomes larger toward the opening end. Thereby, in the path from the corner passage 80 to the opening end of the radial passage 52, a Laval nozzle can be configured in which the passage area is gradually decreased and then gradually increased. Thereby, the flow velocity of air can be increased, and the lift force can be increased.

[0041] In the present embodiment, since the opening end side of the radial groove portion 45 is an inclined portion in which the groove depth dimension becomes larger toward the opening end, the passage area on the opening end side is gradually increasing. Thereby, for example, in the working process of forming the radial groove portion 45 by cutting using a ball end mill, a passage in which the passage area is gradually increased can be realized by a simple operation of adjusting the axial position of the ball end mill while operating the ball end mill in the radial direction. As a result, the working load during the manufacture of the non-contact support device 10 can be reduced.

[0042] Incidentally, when the inclination angle of the bottom surface of the inclined portion in which the groove depth dimension becomes larger toward the opening end with respect to the bottom surface on the corner passage 80 side of the radial groove portion 45 is θ, for example, "10° ≤ θ ≤ 40°" or "15° ≤ θ ≤ 25°", and specifically, for example, "θ = 20°" may be sufficient.

[0043] It is desirable that the maximum passage area EC of the corner passage 80 is at least three times the minimum passage area ER of the radial passage 52. This allows for an increase in the air flow rate flowing from the annular passage portion 50 into the axial passage 51, while gradually reducing the passage area to increase the air flow velocity, thereby further increasing the lift force. For example, it can be set to "3×ER≦EC≦7×ER", "3×ER≦EC≦6×ER", "3×ER≦EC≦5×ER", or "3×ER≦EC≦4×ER". Note that in the radial passage 52, the portion where the groove depth is at its minimum value DN (also referred to as the nozzle diameter DN) is the portion with the minimum passage area in the radial passage 52.

[0044] The large-diameter cylindrical portion 42 with a relatively large radial dimension can suppress the warping of the disc portion 41 when the bolt 70 is screwed in. As a result, it is possible to prevent the passage shape at the opening end side of the radial passage 52 from deviating significantly from the shape intended during design.

[0045] As shown in FIG. 9, the flat surface 23a of the flat portion 23 extends radially outward beyond the opening end of the radial passage 52. This makes it less likely for the air ejected from the opening end of the radial passage 52 to collide with the wall surface of the inner concave portion 22, and the air flow velocity can be increased. As a result, the lift force can be increased.

[0046] Incidentally, for example, it is desirable that the radial dimension LF of the radially outer portion of the flat surface 23a of the flat portion 23 beyond the opening end of the radial passage 52 is larger than the radial dimension LN of the inclined portion of the radial passage 52 where the passage area gradually increases.

[0047] Also, for example, it is desirable that the radial dimension LN of the inclined portion is at least five times the nozzle diameter DN. Furthermore, it is desirable that the passage area of the axial passage 51 is at least three times the nozzle diameter DN.

[0048] Fig. 10 shows the calculation results indicating the relationship between the distance between the workpiece support portion 21 and the workpiece W in the axial direction and the lift force acting on the workpiece W. In Fig. 10, Comparative Example 1 is the configuration where "LF = 0" in the previous Fig. 9.

[0049] The reason why the lift force of the present embodiment is greater than that of Comparative Example 1 is that the supersonic region generating a large negative pressure is distributed in a wide radial range of the inner concave portion 22. With the configuration of LF>0, it is considered that the air collides with the workpiece W after decelerating.

[0050] On the other hand, in Comparative Example 1, the high-speed air ejected from the opening end of the radial passage 52 collides with the workpiece W without sufficient deceleration. As a result, it is considered that the air collides with the workpiece W so as to pull the workpiece W away from the non-contact support device 10, and the lift force decreases.

[0051] Fig. 11 shows a cross-sectional view of Comparative Example 2. Comparative Example 2 is the configuration described in FIGS. 3 to 6 etc. of Japanese Patent Application Laid-Open No. 2021-130162 of the above-mentioned Patent Document 1. The non-contact support device of Comparative Example 2 includes an annular passage portion 150 into which air flows, an inner concave portion 160, a flat portion 161, a radial passage 170, and a radial groove portion 171.

[0052] In Comparative Example 2, the cross-sectional area of the radial passage 170 does not gradually decrease, and the corner portion is not curved. For this reason, the air flow cannot be made smooth, and the air cannot be effectively accelerated. As a result, a sufficient lift force cannot be obtained.

[0053] <Other Embodiments> Note that the above embodiment may be implemented with the following modifications.

[0054] · The bottom portions of the axial groove portion 44 and the radial groove portion 45 are not limited to being arc-shaped, and may be, for example, rectangular or V-shaped.

[0055] ·The opening end side of the radial groove portion 45 may have a gradually increasing radial dimension toward the opening end, so that the passage area on the opening end side of the radial groove portion 45 may gradually increase.

[0056] ·If the passage area of the corner passage gradually decreases from the axial passage side toward the radial passage side, the inner corner portion of the corner passage is not limited to a curved surface shape, and for example, the configuration shown in FIG. 12 may be used. In the configuration shown in FIG. 12, the second inner peripheral surface 32b of the columnar recess 30 and the flat surface 23a of the flat portion 23 are connected by the inner corner portion 133. The inner peripheral surface 133a of the inner corner portion 133 extends linearly.

[0057] Also, the outer corner portion of the corner passage is not limited to a curved surface shape, and for example, the configuration shown in FIG. 12 may be used. In the configuration shown in FIG. 12, the bottom of the axial groove portion 44 and the bottom of the radial groove portion 45 are connected by the outer corner portion 181. The inner peripheral surface 181a of the outer corner portion 181 extends linearly. The inner peripheral surface 181a has an arc shape similar to the axial groove portion 44 and the radial groove portion 45.

[0058] In FIG. 12, B1 indicates a first boundary line that is a boundary line between the second inner peripheral surface 32b of the columnar recess 30 and the inner peripheral surface 133a of the inner corner portion 133. C1 indicates a first boundary point that is a boundary point between the bottom of the axial groove portion 44 and the bottom of the inner peripheral surface 181a. SA1 indicates a first virtual plane passing through the first boundary line B1 and the first boundary point C1. B2 indicates a second boundary line that is a boundary line between the inner peripheral surface 133a of the inner corner portion 133 and the flat surface 23a of the flat portion 23. C2 indicates a second boundary point that is a boundary point between the bottom of the radial groove portion 45 and the bottom of the inner peripheral surface 181a. SA2 indicates a second virtual plane passing through the second boundary line A2 and extending in the axial direction. The passage sandwiched between the first virtual plane SA1 and the second virtual plane SA2 is the corner passage 180. In FIG. 12, the normal line to the inner peripheral surface 133a is also shown by a two-dot chain line.

[0059] On the inner peripheral surface 181a, the boundary points located between the first boundary point C1 and the second boundary point C2 are defined as target boundary points. As the target boundary points are moved from the first boundary point C1 to the second boundary point C2, the distance between the first boundary line B1 and the target boundary points gradually decreases. That is, in the passage of the corner passage 180 surrounded by the virtual plane passing through the first boundary line B1 and the second boundary point C2 and the first virtual plane SA1, the passage area gradually decreases as it approaches the radial passage 52 side.

[0060] · When manufacturing the non-contact support device with a 3D printer, the non-contact support device is not limited to being composed of two body members such as the main body and the sub-body, and may be composed of one body member.

[0061] · The gas supplied to the non-contact support device is not limited to air and may be, for example, nitrogen.

Explanation of Reference Numerals

[0062] 10… Non-contact support device, 20… Main body, 21… Work support part, 40… Sub-body, 51… Axial passage, 52… Radial passage, 80… Corner passage.

Claims

1. In a non-contact support device (10) that supports a workpiece (W) in a non-contact state by ejecting gas against the workpiece, a body (20, 40) extending in an axial direction in which a central axis (K) extends and in a radial direction orthogonal to the axial direction is provided, at a first end portion of the body in the axial direction, a workpiece support portion (21) that forms an annular shape around the central axis and faces the workpiece is formed, in an inner portion of the body in the radial direction relative to the workpiece support portion, an inner concave portion (22) that is recessed toward a second end portion side of the body in the axial direction is formed with respect to the workpiece support portion, in the body, an axial passage (51, 151) that extends in the axial direction and to which gas is supplied, a radial passage (52) that extends toward the outer side in the radial direction and opens into the inner concave portion, a corner passage (80, 180) that connects a downstream end portion of the axial passage and an upstream end portion of the radial passage, are formed side by side in the circumferential direction of the body, The non-contact support device in which a passage area of the corner passage gradually decreases from the axial passage side toward the radial passage side.

2. The non-contact support device according to claim 1, wherein an inner peripheral surface (33a) forming an inner corner portion (33) of the corner passage has a curved surface shape that is smoothly continuous with an inner peripheral surface of the axial passage and an inner peripheral surface of the radial passage.

3. The non-contact support device according to claim 2, wherein an inner peripheral surface (81a) forming an outer corner portion (81) of the corner passage has a curved surface shape that is smoothly continuous with an inner peripheral surface of the axial passage and an inner peripheral surface of the radial passage.

4. The non-contact support device according to any one of claims 1 to 3, wherein a maximum passage area of the corner passage is three times or more a minimum passage area of the radial passage.

5. The body includes a main body (20) and a sub-body (40), at the first end portion of the main body in the axial direction, the annular workpiece support portion is formed, in an inner portion of the main body in the radial direction relative to the workpiece support portion, the inner concave portion is formed, In a portion of the main body adjacent to the inside of the inner concave portion in the radial direction, a columnar concave portion (30) that is recessed in a columnar shape on the second end side in the axial direction with respect to the inner concave portion is formed. In the inner concave portion, a flat portion (23) that extends outward in the radial direction from a corner portion between the inner concave portion and the columnar concave portion and forms an annular shape, an inclined portion (24) that is a portion connecting the flat portion and the work support portion and is inclined with respect to the flat portion, are formed. The sub-body is in the shape of a disc extending outward in the radial direction around the central axis, and has a disc portion (41) whose axial dimension is smaller than the axial distance between the work support portion and the flat portion, a large-diameter cylindrical portion (42) that extends in the axial direction from the central portion of the disc portion and has an outer shape of a columnar shape, and whose radial dimension is smaller than the radial dimension of the disc portion, a small-diameter cylindrical portion (43) that extends in the axial direction from the central portion of the large-diameter cylindrical portion and has an outer shape of a columnar shape, and whose radial dimension is smaller than the radial dimension of the large-diameter cylindrical portion, has. On the outer peripheral portion of the large-diameter cylindrical portion, an axial groove portion (44) that extends from the end on the small-diameter cylindrical portion side in the axial direction to the disc portion in the axial direction is formed. In the disc portion, a radial groove portion (45) that extends in the radial direction from the axial groove portion to the radial end of the disc portion is formed. The axial end portion of the small-diameter cylindrical portion abuts against the bottom portion (31) of the columnar concave portion, and the outer peripheral surface (42a) of the large-diameter cylindrical portion abuts against the inner peripheral surface (32b) of the columnar concave portion. An annular space surrounded by the columnar concave portion, the small-diameter cylindrical portion, and the large-diameter cylindrical portion is an annular passage portion (50) to which gas is supplied. The axial passage and the corner passage are formed by the axial groove portion, the radial groove portion, and the columnar concave portion. The non-contact support device according to any one of claims 1 to 3, wherein the radial passage is formed by the radial groove portion and the flat portion of the concave portion.

6. The non-contact support device according to claim 5, wherein the flat portion extends to the outside in the radial direction beyond the opening end of the radial passage.

7. The non-contact support device according to claim 6, wherein the opening end side of the radial passage has a larger passage area as it goes to the opening end.

8. In the central portion in the radial direction of the sub-body, a bolt insertion hole (60) penetrating the disk portion, the large-diameter cylindrical portion, and the small-diameter cylindrical portion in the axial direction is formed. In the sub-body, on the peripheral edge of the bolt insertion hole on the side of the disk portion, a seating surface (61) against which the head (71) of the bolt (70) abuts is formed. In the central portion in the radial direction of the portion of the main body that faces the sub-body in the axial direction, a female screw hole (62) into which the male screw of the shaft portion (72) of the bolt is screwed is formed. The non-contact support device according to claim 5, wherein the male screw of the shaft portion of the bolt is screwed into the female screw hole in a state where the head of the bolt abuts against the seating surface.

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