JP6434676B2 - Rotary atomizing head type coating machine - Google Patents

Description

  The present invention relates to a rotary atomizing head type coating machine that sprays paint toward an object to be coated from a rotary atomizing head that rotates at high speed.

  In general, a rotary atomizing head type coating machine includes an air motor that rotates a rotating shaft when supplied with compressed air, and a cylindrical body provided on the front side of the rotating shaft, and is supplied while rotating by the air motor. A rotary atomizing head that sprays the applied paint from the discharge edge of the front end, and an outer peripheral side of the rotary atomizing head, and shaping air is jetted toward the paint particles sprayed from the rotary atomizing head at the front end A plurality of air ejection holes are formed including a shaping air ejection member provided over the entire circumference in the circumferential direction (Patent Document 1).

  When coating is performed using the rotary atomizing head type coating machine configured as described above, the rotary atomizing head is rotated at a high speed by an air motor, and the coating material is supplied to the rotary atomizing head in this state. Thereby, the coating material supplied to the rotary atomizing head is atomized by the centrifugal force when the rotary atomizing head rotates, and sprayed as coating particles from the discharge edge. At this time, the shaping air ejection member sprays the shaping air ejected from each air ejection hole onto the paint particles. As a result, the shaping air controls the motion vector component of the paint particles in the direction of the object, and arranges the spray pattern of the paint particles into a desired shape.

JP-A-8-332418

  Here, in the rotary atomizing head type coating machine according to Patent Document 1, a part of the paint particles sprayed from the rotary atomizing head wrap around the rear side of the rotary atomizing head, and a shaping air ejection member, a cover It may adhere to the member. In this case, the paint adhering to the shaping air ejection member or the cover member drops from the coating machine and adheres to the object to be coated, thereby causing poor painting. For this reason, in the painting line, it is necessary to perform the washing operation of the coating machine at a high frequency, and there is a problem that productivity of the painting operation is lowered.

  The present invention has been made in view of the above-described problems of the prior art, and an object of the present invention is to provide a rotary atomizing head type coating machine capable of suppressing the adhesion of paint to a shaping air ejection member. is there.

  The present invention comprises an air motor that rotates a rotating shaft when supplied with compressed air, and a cylindrical body that is provided on the front side of the rotating shaft, and discharges paint supplied while rotating by the air motor to the front end. A rotary atomizing head that sprays from the edge, and a plurality of air ejection holes that are arranged on the outer peripheral side of the rotary atomizing head and that eject shaping air toward the paint particles sprayed from the rotary atomizing head at the front end In the rotary atomizing head type coating machine configured to include a shaping air ejection member provided over the entire circumference in the circumferential direction, the front portion of the shaping air ejection member is connected to the outer surface of the front portion. An annular flange member extending outward in the radial direction is provided integrally or separately from the shaping air ejection member.

  ADVANTAGE OF THE INVENTION According to this invention, it can prevent that the sprayed coating material wraps around the back side of a rotary atomization head, and can suppress adhesion of the coating material to the shaping air ejection member.

It is sectional drawing which shows the rotary atomizing head type coating machine by the 1st Embodiment of this invention. It is a perspective view which shows a rotary atomizing head type coating machine. It is sectional drawing which shows the front side part of a rotary atomizing head type coating machine with the flow of air at the time of a painting operation. It is sectional drawing which shows the rotary atomization head type coating machine by 2nd Embodiment. It is sectional drawing which shows the front side part of the rotary atomization head type coating machine by 3rd Embodiment. It is sectional drawing which shows the front side part of the rotary atomization head type coating machine by 4th Embodiment. It is sectional drawing which shows the front side part of the rotary atomization head type coating machine by 5th Embodiment. It is sectional drawing which shows the front side part of the rotary atomization head type coating machine by a comparative example with the flow of the air at the time of a painting operation.

  Hereinafter, as a representative example of a rotary atomizing head type coating machine according to an embodiment of the present invention, the configuration of an indirect charging type rotary atomizing head type electrostatic coating machine will be described in detail with reference to the accompanying drawings.

  1 to 3 show a first embodiment of the present invention. In the first embodiment, a case where an annular flange member is integrally provided on the outer peripheral surface of the front portion of the shaping air ejection member will be described as an example. In the present embodiment, for the rotary atomizing head type coating machine 1 to be described later, the direction close to the object to be coated (or the shaping air ejection direction) is the front side, and the object is separated from the object on the opposite side to the front side. The arrangement relationship will be described with the rear direction as the rear side.

  In FIG. 1, a rotary atomizing head type coating machine 1 (hereinafter simply referred to as a coating machine 1) according to the first embodiment indirectly receives paint sprayed from a rotary atomizing head 4 by an external electrode member 6 described later. It is configured as a rotary atomizing head type electrostatic coating machine of an indirect charging system in which a negative polarity is charged. The painting machine 1 is attached to the tip of an arm (not shown) of a painting robot, for example.

  The coating machine support 2 surrounds the air motor 3 on the outer peripheral side of the air motor 3 to be described later, and is provided to extend rearward from the air motor 3. The coating machine support 2 is attached to the tip of the arm described above via the attachment cylinder portion 2A on the base end side. Here, the coating machine support 2 is made of, for example, a rigid insulating resin material.

  A motor accommodating portion 2B is provided on the front end side of the coating machine support 2 so as to open forward. A female screw portion 2C is provided on the opening side of the motor housing portion 2B. Further, the coating machine support 2 is provided with an insertion hole 2D into which a proximal end side of a feed tube 5 described later is inserted at a central position (coaxial with a rotation shaft 3C described later) of the bottom of the motor housing 2B. ing.

  The air motor 3 is provided in the motor housing portion 2B of the coating machine support 2. The air motor 3 rotates a rotating shaft 3C and a rotary atomizing head 4 described later at a high speed of 3000 to 150,000 rpm, for example, using compressed air as a power source. The air motor 3 is made of a conductive metal material including, for example, an aluminum alloy, and is held at a ground potential.

  The air motor 3 includes a stepped cylindrical motor case 3A attached to the front side of the coating machine support 2 and a turbine 3B of, for example, an impeller type that is rotatably located near the rear side of the motor case 3A. And a rotating shaft 3C that is rotatably provided at the axial center position of the motor case 3A and that extends in the front and rear directions and is attached to the turbine 3B.

  The motor case 3A of the air motor 3 is formed as a cylindrical body arranged coaxially with the rotating shaft 3C. The motor case 3A is a stepped cylinder by a large-diameter large-diameter cylinder 3A1 inserted into the motor housing 2B of the coating machine support 2 and a small-diameter small-diameter cylinder 3A2 protruding forward from the large-diameter cylinder 3A1. It is formed in a shape.

  The motor case 3 </ b> A is inserted into the motor housing portion 2 </ b> B of the coating machine support 2. In this state, the motor case 3A is fixed in the motor housing portion 2B by an annular screw member 3D screwed to the female screw portion 2C of the coating machine support 2.

  The rotating shaft 3C is formed as a hollow cylindrical body rotatably supported in the motor case 3A via an air bearing (not shown). As for this rotating shaft 3C, the rear end side is attached to the center of the turbine 3B, and the front end side protrudes from the motor case 3A to the front side. A rotary atomizing head 4 is attached to the front end portion of the rotary shaft 3C using, for example, screwing means.

  The rotary atomizing head 4 is provided on the front side of the rotary shaft 3 </ b> C of the air motor 3. The rotary atomizing head 4 is formed as a cylindrical body with a conductive metal material including, for example, an aluminum alloy, and is held at a ground potential through the air motor 3. As shown in FIG. 3, the rotary atomizing head 4 is formed as a long cylindrical body, for example, and has a mounting portion 4A whose rear side extends linearly in the axial direction. 4 A of attachment parts are attached to the front-end part of the rotating shaft 3C, for example using a screwing means.

  The front side of the rotary atomizing head 4 is an expanded portion 4B that gradually expands forward, and the inner peripheral surface of the expanded portion 4B is a paint thinning surface 4C that thins the supplied paint. Yes. Further, the front end (front end) of the paint thin film surface 4C is a discharge edge 4D that discharges the thin paint as paint particles.

  The rotary atomizing head 4 is rotated at high speed by the air motor 3. In this state, when a coating material is supplied to the rotary atomizing head 4 through a feed tube 5 described later, the coating material is sprayed from the discharge edge 4D by centrifugal force while being thinned on the coating film thinning surface 4C. At this time, the paint particles sprayed from the discharge edge 4D are accelerated toward the object to be disposed in front by shaping air from a shaping air ejection member 9 described later from the rear side. The In addition, the paint particles sprayed from the discharge edge 4D are negatively charged by the external electrode member 6 described later, thereby forming an electrostatic field formed between the object to be coated and held at the ground potential. Can fly along.

  The feed tube 5 is provided so as to be inserted into the rotary shaft 3 </ b> C, and the rear end side thereof is inserted into the insertion hole 2 </ b> D of the coating machine support 2. On the other hand, the front end side of the feed tube 5 protrudes from the rotary shaft 3 </ b> C and extends into the rotary atomizing head 4. A paint passage is provided in the feed tube 5, and the paint passage is connected to a paint supply source and a cleaning fluid supply source (both not shown) via a color change valve device. Thereby, at the time of painting, the paint supplied from the paint supply source through the paint passage is discharged from the feed tube 5 to the rotary atomizing head 4. On the other hand, when the rotary atomizing head 4 is cleaned, when the color is changed, the cleaning fluid (thinner, air, etc.) supplied from the cleaning fluid supply source is discharged from the feed tube 5.

  The external electrode member 6 is located on the rear side of the rotary atomizing head 4 and is provided on the outer peripheral side of the coating machine support 2. The external electrode member 6 is provided on the outer peripheral side of the coating machine support 2 and is formed of an annular external electrode support cylinder 6A made of an insulating resin material, and a plurality of external electrode members 6A at equal intervals in the circumferential direction (external electrode support cylinder 6A). For example, the electrode mounting holes 6B (only two are shown) and the electrodes 6C attached to the respective electrode mounting holes 6B are arranged. A number of holes 6A1 corresponding to the needle-like portions 6C1 of the respective electrodes 6C are provided on the front side of the external electrode supporting cylinder 6A.

  Here, the external electrode member 6 according to the first embodiment is configured so that the coating machine support 2 is located near the rear side of the coating machine support 2 in order to use the coating machine 1 in a narrow space like the inside of the vehicle body. Near the outer peripheral side. A negative high voltage is applied to the external electrode member 6 from a high voltage generator (not shown) to each electrode 6C. Thereby, the external electrode member 6 generates corona discharge by each electrode 6C, and charges the paint particles sprayed from the discharge edge 4D of the rotary atomizing head 4 to the negative polarity.

  The inner cover member 7 constitutes a cover member together with an outer cover member 8 described later. The inner cover member 7 is formed as, for example, a cylindrical body that is made of an insulating resin material and has a reduced diameter in an arc shape toward the front side. The inner cover member 7 is provided between the external electrode member 6 and a shaping air ejection member 9 described later so as to surround the air motor 3. The inner cover member 7 has a rear side attached to the outer peripheral side of the coating machine support 2 and a front side attached to a rear portion of the outer peripheral surface 9B of the shaping air ejection member 9.

  The outer cover member 8 constitutes a cover member together with the inner cover member 7 and, like the inner cover member 7, is formed as a cylindrical body whose diameter is reduced in an arc shape toward the front side by an insulating resin material. ing. The outer cover member 8 is provided between the external electrode member 6 and the shaping air ejection member 9 so as to surround the air motor 3 from the outer side of the inner cover member 7.

  The outer cover member 8 has a rear side attached between the inner cover member 7 and the inner peripheral side of the external electrode member 6, and a front side attached to the front portion of the outer peripheral surface 9 </ b> B of the shaping air ejection member 9. The outer cover member 8 can be removed when the rotary atomizing head 4 and the shaping air ejection member 9 are assembled or disassembled.

  The shaping air ejection member 9 has an outer periphery of the rotary atomizing head 4 in a state where a front end (a front side portion 9D described later) is located at an intermediate portion in the length direction of the rotary atomizing head 4 (the rear side of the expanded portion 4B). Arranged on the side. The shaping air ejection member 9 is made of a conductive metal material including, for example, an aluminum alloy, and is held at the ground potential via the air motor 3.

  The shaping air ejection member 9 is formed as a stepped cylindrical body surrounding the rotary atomizing head 4. The inner peripheral surface 9 </ b> A of the shaping air ejection member 9 faces the outer peripheral surface of the rotary atomizing head 4 with a slight gap. On the other hand, the outer peripheral surface 9B of the shaping air ejection member 9 has an inner cover attachment portion 9B1 on the rear side and a tapered portion 9B2 that gradually decreases in diameter toward the front side.

  The front side part of the inner cover member 7 is attached to the inner cover attachment part 9B1 in an externally fitted state. The tapered portion 9B2 is covered by the outer cover member 8 up to the front side position of the intermediate portion in the front and rear directions, and the front side is exposed to the outside.

  On the other hand, the rear end portion of the shaping air ejection member 9 is a cylindrical mounting screw portion 9C, and the mounting screw portion 9C is screwed to the female screw portion 2C of the coating machine support 2. Thereby, the shaping air ejection member 9 is attached to the front part of the coating machine support 2 using the attachment screw portion 9C.

  Here, the basic shape of the front portion 9D of the shaping air ejection member 9 will be described in detail. In this case, the front portion 9D of the shaping air ejection member 9 has a range extending in a cylindrical shape from the front portion of the taper portion 9B2, that is, a cylindrical shape indicated by a two-dot chain line in FIGS. The virtual boundary surface 9F is provided. The cylindrical virtual boundary surface 9F of the shaping air ejection member 9 has a similar shape shown in FIG. 8 as a comparative example. That is, the virtual boundary surface 9F of the shaping air ejection member 9 corresponds to the cylindrical surface 9F ′ on the front side of the tapered portion 9B2 of the shaping air ejection member 9 in FIG. Thereby, when the below-mentioned collar member 14 is provided in the front side part 9D of the shaping air ejection member 9, the cylindrical virtual boundary surface 9F becomes a boundary part between the shaping air ejection member 9 and the collar member 14, and the virtual boundary surface 9F The outer diameter side is the flange member 14.

  Further, the front portion 9D of the shaping air ejection member 9 is formed as a cylindrical body having a substantially constant outer diameter so as to be connected to the virtual boundary surface 9F. As shown in FIGS. 2 and 3, the front end of the front portion 9 </ b> D is a flat annular front end surface portion 9 </ b> E. The front end surface portion 9E is provided with a first air ejection hole 10 and a second air ejection hole 12 that are open. The front end face portion 9E is arranged around the rear position of the spread site 4B of the rotary atomizing head 4. Here, as for the front side site | part 9D of the shaping air ejection member 9, the diameter (outside diameter of the virtual interface 9F) is set to the dimension D (mm). A flange member 14 described later is provided on the outer diameter side of the front side portion 9D (virtual boundary surface 9F) so as to be flush with the front end surface portion 9E.

  A large number of first air ejection holes 10 are provided at equal intervals over the entire circumference in the circumferential direction, located closer to the outer diameter side of the front end surface portion 9E. The first air ejection hole 10 is connected to a first shaping air supply source (not shown) through a first shaping air passage 11. The first air ejection hole 10 ejects the first shaping air toward the vicinity of the discharge edge 4 </ b> D of the rotary atomizing head 4.

  A plurality of the second air ejection holes 12 are located on the inner side in the radial direction from the first air ejection hole 10 and are provided at equal intervals over the entire circumference in the circumferential direction on the front end surface portion 9E. The second air ejection hole 12 is connected to a second shaping air supply source (not shown) through the second shaping air passage 13. The second air ejection hole 12 ejects the second shaping air toward the back surface of the rotary atomizing head 4.

  Accordingly, the first shaping air ejected from the first air ejection hole 10 and the second shaping air ejected from the second air ejection hole 12 are released from the discharge edge 4D of the rotary atomizing head 4. The liquid yarn of the paint is sheared to promote the formation of paint particles, and the spray pattern of the paint particles sprayed from the rotary atomizing head 4 is shaped. At this time, the spray pattern can be changed to a desired size and shape by appropriately adjusting the pressure of the first shaping air and the pressure of the second shaping air. Further, the first and second shaping airs are sprayed on the paint particles flying radially outward from the discharge edge 4D of the rotary atomizing head 4 by centrifugal force, so that the direction of the paint particles is gradually covered. Accelerate the paint particles while facing the paint.

  Next, the configuration of the eaves member 14 that is a characteristic part of the first embodiment will be described in detail.

  The eaves member 14 is provided in the front portion 9D of the shaping air ejection member 9. The flange member 14 is formed as an annular plate-like body that is located on the outer peripheral side of the front portion 9D and extends in the radial direction. The eaves member 14 extends outward in the radial direction with a virtual boundary surface 9F positioned on the outer diameter side of the front portion 9D, that is, on the front side of the tapered portion 9B2 of the outer peripheral surface 9B. The eaves member 14 prevents a part of the paint particles sprayed from the rotary atomizing head 4 from flowing around to the rear side of the rotary atomizing head 4 due to the air flow generated by the shaping air.

  The eaves member 14 is formed integrally with the shaping air ejection member 9. Further, the eaves member 14 includes a front surface portion 14A that is a flat surface that is coplanar with the front end surface portion 9E of the shaping air ejection member 9, a rear surface portion 14B that is located on the opposite side of the front surface portion 14A in the front and rear directions, The front surface portion 14 </ b> A and the peripheral portion 14 </ b> C that is the outermost peripheral portion of the rear surface portion 14 </ b> B are provided. Thereby, the eaves member 14 suppresses the coating particles from getting around the rear side of the rotary atomizing head 4 on the air flow generated by the shaping air. Further, in the rear surface portion 14B, the connection portion of the outer peripheral surface 9B with the tapered portion 9B2 is a smooth arcuate surface 14B1. The arcuate surface 14B1 can improve the cleaning performance of the attached paint by eliminating the angular corners.

  Here, the size of the flange member 14 will be described. The diameter dimension E (mm) of the eaves member 14 is set as the following formula 1 with respect to the diameter dimension D (mm) of the front portion 9D of the shaping air ejection member 9.

  Thereby, the eaves member 14 extends outward in the radial direction, thereby suppressing the air around the front portion 9D of the shaping air ejection member 9 and the outer cover member 8 from being pulled forward by the shaping air. Can do. Moreover, since the front surface part 14A is arrange | positioned in the position where the front surface part 14E becomes the same plane as the front-end surface part 9E of the shaping air ejection member 9, the scissors member 14 can improve the washability of the adhering coating material.

  Next, the operation in the case where the object to be coated is coated by the rotary atomizing head type coating machine 1 will be described.

  First, as a comparative example, a painting operation by a conventional rotary atomizing head type coater 101 will be described with reference to FIG. The coating machine 101 has the same configuration as the coating machine 1 according to the first embodiment except that the gutter member 14 is not provided.

  Turbine air is supplied to the turbine 3B of the air motor 3 to rotate the rotating shaft 3C. Thereby, the rotary atomizing head 4 rotates at high speed together with the rotary shaft 3C. In this state, the paint selected by the color change valve device (not shown) is supplied from the paint passage of the feed tube 5 to the rotary atomizing head 4. Thus, the supplied paint is sprayed as paint particles from the discharge edge 4D by centrifugal force while being thinned by the paint thinning surface 4C of the rotary atomizing head 4.

  In this case, the paint particles immediately after being separated from the discharge edge 4D of the rotary atomizing head 4 are not directed to the object disposed in front, and are radially outside by the centrifugal force of the rotary atomizing head 4. Trying to fly radially toward. Therefore, as indicated by an arrow 15 indicated by a one-dot chain line in FIG. 8, the shaping air ejection member 9 causes the air propelling force to spray the shaping air from the air ejection holes 10 and 12 toward the paint particles. The paint particles are gradually accelerated toward the front object to be coated. Further, the shaping air can appropriately shape the spray pattern of the paint particles while atomizing the paint particles.

  When the paint particles are sprayed from the discharge end edge 4D of the rotary atomizing head 4, a negative high voltage by the high voltage generator is applied to each electrode 6C of the external electrode member 6. Each electrode 6C forms lines of electric force with the object to be coated that is held at the ground potential, and charges the paint particles sprayed from the discharge edge 4D to a negative polarity. Accordingly, the coating particles can be efficiently supplied to the object to be coated along the lines of electric force, and the coating efficiency can be improved.

  Here, when the shaping air is ejected from the air ejection holes 10 and 12 of the shaping air ejection member 9, as shown by the two-dot chain line arrow 16 by being pulled by the shaping air ejected forward. Then, an air flow directed forward around the front side of the coating machine 101 and an air flow directed rearward around the front side of the coating machine 101 are generated as indicated by an arrow 17 indicated by a two-dot chain line.

  The air flow indicated by the arrow 16 moves the air around the outer cover member 8 and the shaping air ejection member 9 forward, so that the rotation fog is directed toward the outer cover member 8 and the shaping air ejection member 9. The air around the chemical head 4 is pulled. On the other hand, the air flow indicated by an arrow 17 collides with the outer cover member 8 and the shaping air ejection member 9 and moves toward the rear of the outer cover member 8. In addition to this, the air flow indicated by the arrow 17 flows in an arc or vortex around the outer cover member 8. Since the air flowing around the rotary atomizing head 4 and the outer cover member 8 contains paint particles, the paint particles adhere to the front portion of the outer cover member 8 and the shaping air ejection member 9.

  Next, the flow of air when coating is performed by the coating machine 1 according to the first embodiment provided with the flange member 14 will be described with reference to FIG.

  When the shaping air is ejected from the respective air ejection holes 10 and 12 of the shaping air ejection member 9, it is pulled by the shaping air ejected toward the front in substantially the same manner as the comparative example of FIG. As indicated by a chain line arrow 18, an air flow is generated around the front of the coating machine 1.

  However, in the middle of the air flow indicated by the arrow 18, the eaves member 14 is provided at the front end of the shaping air ejection member 9. The flange member 14 functions as a wall that blocks the flow of air toward the front portion 9 </ b> D of the shaping air ejection member 9 and the outer cover member 8. That is, the eaves member 14 can block the air flow toward the front portion 9D of the shaping air ejection member 9. In other words, the collar member 14 can suppress the flow of air from the periphery of the shaping air ejection member 9 toward the front.

  Thereby, the air in the vicinity of the peripheral edge portion 14 </ b> C and the like of the flange member 14 is pulled forward by the shaping air near the periphery of the flange member 14. Thereby, the paint particles contained in the air around the rotary atomizing head 4 can be prevented from adhering to the front portion of the outer cover member 8 and the shaping air ejection member 9.

  Further, other factors that suppress the coating particles from flowing into the shaping air ejection member 9 and the outer cover member 8 will be described. In the vicinity of the front side of the front end face portion 9E of the shaping air ejection member 9, the surrounding air is accompanied by the shaping air ejected from the air ejection holes 10 and 12 at a high speed (Bernoulli's theorem), so that a strong negative pressure region is formed. The In this negative pressure region, the air around the rotary atomizing head 4 is pulled (pulled). At this time, an inward air flow from the periphery of the rotary atomizing head 4 toward the negative pressure region is generated on the front surface portion 14A side of the flange member 14.

  Thereby, even if a part of the sprayed paint particles tries to fly toward the front portion 9D and the outer cover member 8 side of the shaping air ejection member 9, it is pulled by the inward air flow. Furthermore, the paint particles contained in the air flowing inward fly toward the rotary atomizing head 4, but are blown off to the front side by the shaping air ejected from the air ejection holes 10 and 12. Therefore, the eaves member 14 can suppress contamination of the rotary atomizing head 4 due to the paint particles.

  Thus, according to the first embodiment, on the outer peripheral side of the rotary atomizing head 4, a large number of air ejection holes that eject shaping air toward the paint particles sprayed from the rotary atomizing head 4 at the front end. A shaping air ejection member 9 in which 10 and 12 are provided over the entire circumference in the circumferential direction is provided. On this, the front side part 9D of the shaping air ejection member 9 is provided with an annular flange member 14 extending radially outward from the outer peripheral surface 9B of the front side part 9D.

  Therefore, the flange member 14 can block the air flow toward the front portion 9D of the shaping air ejection member 9 and the outer cover member 8, and can form a negative pressure region on the front surface portion 14A side of the flange member 14. it can. For this reason, it is possible to prevent a part of the paint particles sprayed from the rotary atomizing head 4 from going around to the rear side of the rotary atomizing head 4. As a result, the collar member 14 can suppress adhesion of the paint particles to the shaping air ejection member 9 and the outer cover member 8.

  As described above, since the coating failure due to the coating particles adhering to the shaping air ejection member 9 and the outer cover member 8 can be prevented, the number of times (frequency) of the cleaning operation of the coating machine 1 in the coating line can be reduced. . As a result, the time required for cleaning during the painting operation can be shortened, so that productivity can be improved.

  The eaves member 14 is formed as a plate-like body whose front surface portion 14A is a flat surface. Further, the front surface portion 14 </ b> A of the flange member 14 made of a plate-like body is formed as the same surface as the front end surface portion 9 </ b> E of the shaping air ejection member 9. Therefore, the eaves member 14 made of a plate can be easily provided, and adhesion of the paint to the shaping air ejection member 9 can be prevented at a low cost. Moreover, since the eaves member 14 is flush with the front end surface portion 9E of the shaping air ejection member 9, it is possible to prevent a situation in which the paint enters the mounting gap between the shaping air ejection member 9 and the eaves member 14. Cleaning time can be shortened.

  On the other hand, a cylindrical inner cover member 7 and an outer cover member 8 are provided at positions surrounding the air motor 3 and the shaping air ejection member 9 to cover them. Thereby, the air motor 3 can be covered by the cover members 7 and 8. In addition, the outer cover member 8 having an outer surface formed in a smooth arc shape can reliably clean the adhered paint in a short time even if the paint adheres.

  Next, FIG. 4 shows a second embodiment of the present invention. The feature of the second embodiment resides in that a purge air ejection portion that ejects purge air from the rear side to the front side along the outer circumferential surface of the cover member is provided on the outer circumferential side of the cover member. In the second embodiment, the same components as those in the first embodiment described above are denoted by the same reference numerals, and the description thereof is simplified.

  In FIG. 4, the outer cover member 21 according to the second embodiment has a cylindrical shape whose diameter is reduced in an arc shape toward the front side by an insulating resin material, in substantially the same manner as the outer cover member 8 according to the first embodiment. It is formed as a body. However, the outer cover member 21 according to the second embodiment has a long portion fitted in the external electrode member 6, and a communication passage 22 </ b> A of a purge air ejection portion 22 described later is formed in the rear portion. This is different from the outer cover member 8 according to the first embodiment. On the outer peripheral surface 21 </ b> A of the outer cover member 21, air flows toward the front side by a purge air ejection portion 22 described later.

  The purge air ejection part 22 is provided on the outer peripheral side of the outer cover member 21. The purge air ejection part 22 ejects purge air from the rear side to the front side of the outer cover member 21 along the outer peripheral surface 21 </ b> A of the outer cover member 21.

  The purge air ejection part 22 is located on the front side of the external electrode member 6 and is provided between the outer peripheral surface 21 </ b> A of the outer cover member 21 and the external electrode support cylinder 6 </ b> A of the external electrode member 6. The purge air ejection portion 22 includes a plurality of communication passages 22A communicating with a purge air supply passage (not shown) separate from the first shaping air passage 11, and an annular space portion communicating with each communication passage 22A. The annular chamber 22B is formed, and a jet port 22C opened from the annular chamber 22B to the front surface of the external electrode support cylinder 6A of the external electrode member 6.

  The annular chamber 22B temporarily stores the compressed air supplied from the communication passages 22A so that uniform purge air can be ejected from the ejection port 22C over the entire circumference. Further, the jet outlet 22C is opened toward the front side as an entire circumferential groove (annular groove) with a small gap. Furthermore, the jet outlet 22C is designed to be inclined inward in the radial direction so that the jet direction of the purge air faces the outer peripheral surface 21A of the outer cover member 21.

  As a result, when the compressed air is supplied from the purge air supply path to the annular chamber 22B through each communication path 22A, the purge air ejection part 22 ejects the purge air from the ejection port 22C toward the front side. Since this purge air is ejected toward the outer peripheral surface 21A of the outer cover member 21, due to the surface adhesion effect (Coanda effect) or the like, for example, as indicated by the two-dot chain line arrow 23, the purge air is moved forward along the outer peripheral surface 21A. It flows toward.

  In this way, the purge air ejected from the purge air ejection portion 22 forms an air curtain along the outer peripheral surface 21 </ b> A of the outer cover member 21. The air curtain by the purge air flows toward the outer peripheral side of the flange member 14. Therefore, the purge air can suppress the flow of air toward the front portion 9 </ b> D of the shaping air ejection member 9 and the outer cover member 21. Thereby, it can control that paint particles adhere to front side part 9D and outside cover member 21. In this case, the purge air has a significantly lower flow rate than the shaping air ejected from the air ejection holes 10 and 12, and is set to a flow rate of, for example, 1/10 or less. For this reason, the purge air does not affect the shaping air.

  Thus, also in the second embodiment configured as described above, it is possible to obtain substantially the same operational effects as those of the first embodiment described above. In particular, according to the second embodiment, the outer peripheral surface 21A of the outer cover member 21 is provided with the purge air ejection portion 22 that ejects purge air from the rear side toward the front side along the outer peripheral surface 21A of the outer cover member 21. It is set as the structure to provide. Therefore, by causing the purge air ejected from the purge air ejection portion 22 to flow along the outer peripheral surface 21A of the outer cover member 21, contamination of the outer peripheral surface 21A can be suppressed by the air curtain caused by the purge air, and productivity is increased. Can be improved.

  Next, FIG. 5 shows a third embodiment of the present invention. The feature of the third embodiment is that the eaves member is formed of a resin material provided separately from the shaping air ejection member, and is disposed at a position spaced rearward from the front end of the shaping air ejection member. In the third embodiment, the same components as those in the first embodiment described above are denoted by the same reference numerals, and the description thereof is simplified.

  In FIG. 5, the eaves member 31 according to the third embodiment is provided separately from the shaping air ejection member 9, and has an annular shape extending outward in the radial direction from the outer peripheral surface 9 </ b> B of the front portion 9 </ b> D of the shaping air ejection member 9. It consists of a plate. Moreover, the eaves member 31 is formed from a resin material (for example, an insulating resin material). Furthermore, the collar member 31 is arrange | positioned in the position spaced apart from the front-end surface part 9E of the shaping air ejection member 9, for example.

  Here, the installation position of the flange member 31 in the axial direction (front and rear directions) can be set as appropriate. That is, when the front end surface portion 9E of the shaping air ejection member 9 is set as the reference position, the distance dimension L (mm) in the front and rear directions between the front end surface portion 9E and the flange member 31 is set as the following formula 2. ing. In the following equation 2, the state in which the flange member 31 is disposed on the front side of the front end surface portion 9E with the front end surface portion 9E as the reference position is set to − (minus), and the flange member 31 is disposed on the rear side of the front end surface portion 9E. The completed state is described as + (plus).

  In this case, the step between the front end surface portion 9E of the shaping air ejection member 9 and the eaves member 31 can be reduced by reducing the distance dimension L, that is, L≈0 mm. Thereby, the detergency of the adhering paint can be improved.

  Thus, also in the third embodiment configured as described above, it is possible to obtain substantially the same operational effects as those of the first embodiment described above. In particular, according to the third embodiment, the flange member 31 is provided separately from the shaping air ejection member 9. Therefore, the eaves member 31 can be retrofitted with respect to the existing shaping air ejection member 9. The eaves member 31 made of a resin material can reduce the weight, reduce the manufacturing cost, and the like. Furthermore, the attachment position of the collar member 31 can be freely set in the axial direction.

  Next, FIG. 6 shows a fourth embodiment of the present invention. A feature of the fourth embodiment is that the collar member is formed as a cone whose inner peripheral surface is recessed into a concave cone, and the front end of the shaping air ejection member is located at the back of the inner peripheral surface of the cone It is in that. In the fourth embodiment, the same components as those in the first embodiment are denoted by the same reference numerals, and the description thereof is simplified.

  In FIG. 6, the flange member 41 according to the fourth embodiment is located on the outer peripheral side of the front portion 9 </ b> D of the shaping air ejection member 9 in the radial direction, almost like the flange member 14 according to the first embodiment. It is formed as an annular body extending in the direction. That is, the flange member 41 uses the virtual boundary surface 9F provided on the outer diameter side of the front portion 9D of the shaping air ejection member 9 as a boundary with the shaping air ejection member 9, and is on the outer diameter side from the virtual boundary surface 9F. Is provided. However, the flange member 41 according to the fourth embodiment is different from the flange member 14 according to the first embodiment in that it is formed as a conical body that expands toward the front side.

  The eaves member 41 is formed as a cone having a front inner peripheral surface 41A recessed into a concave cone. The flange member 41 has a rear outer peripheral surface 41B and a peripheral edge portion 41C. Here, the front end surface portion 9E of the shaping air ejection member 9 is located in the back of the inner peripheral surface 41A of the flange member 41 made of a cone.

  Thus, also in the fourth embodiment configured as described above, it is possible to obtain substantially the same operational effects as those of the first embodiment described above. In particular, according to the fourth embodiment, the flange member 41 is formed as a conical body that expands toward the front side, so that the expansion angle (inclination angle) of the cone is appropriately set to a desired value. Can be set.

  Next, FIG. 7 shows a fifth embodiment of the present invention. The feature of the fifth embodiment resides in that the eaves member is formed by extending the cover member to the front side portion of the shaping air ejection member and extending the distal end portion of the cover member radially outward. In the fifth embodiment, the same components as those in the first embodiment described above are denoted by the same reference numerals, and the description thereof is simplified.

  In FIG. 7, the outer cover member 51 according to the fifth embodiment has a cylindrical shape whose diameter is reduced in an arc shape toward the front side by an insulating resin material in substantially the same manner as the outer cover member 8 according to the first embodiment. It is formed as a body. However, the outer cover member 51 according to the fifth embodiment is formed so as to extend forward to the front end surface portion 9E so as to surround the front portion 9D of the shaping air ejection member 9. The outer cover member 8 is different from the outer cover member 8. The outer cover member 51 is provided with a flange member 52 described later at the front end portion 51A.

  The eaves member 52 according to the fifth embodiment is provided on the front side portion 9 </ b> D of the shaping air ejection member 9, that is, on the outer peripheral side of the front end portion 51 </ b> A of the outer cover member 51. The flange member 52 is integrally formed with an outer cover member 51 made of a resin material (for example, an insulating resin material). The shape of the eaves member 52 is omitted because there is no difference with the eaves member 14 according to the first embodiment.

  Thus, also in the fifth embodiment configured as described above, it is possible to obtain substantially the same function and effect as those of the first embodiment described above. In particular, according to the fifth embodiment, since the eaves member 52 is provided as a part of the outer cover member 51, the eaves member 52 can be easily changed by simply replacing the outer cover member 51 with an existing cover member. Can be provided.

  In the fourth embodiment, the case where the flange member 41 is formed as a conical body that expands toward the front side is described as an example. However, the present invention is not limited to this, and for example, the flange member may be formed as a conical body that expands toward the rear.

  In the second embodiment, a purge air ejection part 22 is provided between the outer peripheral surface 21A of the outer cover member 21 and the external electrode support cylinder 6A of the external electrode member 6, and the outer cover member 21 is formed from the purge air ejection part 22. The purge air is jetted toward the outer peripheral surface 21A. However, the present invention is not limited to this. For example, the purge air may be ejected from the hole 6A1 of the external electrode support cylinder 6A constituting the external electrode member 6. Thereby, the purge air ejected from the hole 6A1 can prevent the paint from adhering to the needle-like portion 6C1 of the electrode 6C. In this case, the purge air ejected from the hole 6A1 of the external electrode support cylindrical body 6A and the purge air ejected from the purge air ejection portion 22 may be configured to communicate with each other or may be configured to share a pressurized air source. These configurations can be similarly applied to other embodiments.

  Moreover, in 1st Embodiment, the case where the rotary atomizing head type coating machine 1 is comprised as an indirect charging type rotary atomizing head type electrostatic coating machine provided with the external electrode member 6 is described as an example. did. However, the present invention is not limited to this. For example, the present invention may be applied to a directly charged rotary atomizing head type electrostatic coating machine that directly applies a high voltage to paint supplied from a feed tube to the rotary atomizing head. You can also. Furthermore, the present invention can also be applied to a non-electrostatic coating machine that performs coating without applying a high voltage. These configurations can be similarly applied to other embodiments.

DESCRIPTION OF SYMBOLS 1 Rotating atomizing head type coating machine 3 Air motor 3C Rotating shaft 4 Rotating atomizing head 4D Discharge end edge (front end)
7 Inner cover member (cover member)
8, 21, 51 Outer cover member (cover member)
DESCRIPTION OF SYMBOLS 9 Shaping air ejection member 9B Outer peripheral surface 9D Front side part 9E Front end surface part 10 1st air ejection hole (air ejection hole)
12 Second air ejection hole (air ejection hole)
14, 31, 41, 52 Scissor member 14A Front surface part 14B Rear surface part 21A Outer peripheral surface 22 Purge air ejection part 41A Inner circumferential surface D Diameter dimension of front end surface part of shaping air ejection member E Diameter dimension of collar member

Claims (6)

An air motor that rotates a rotating shaft by being supplied with compressed air;
A rotary atomizing head that consists of a cylindrical body provided on the front side of the rotating shaft, and sprays paint supplied from the discharge end edge of the front end while rotating by the air motor;
A plurality of air ejection holes that are arranged on the outer peripheral side of the rotary atomizing head and that eject shaping air toward the paint particles sprayed from the rotary atomizing head at the front end are provided over the entire circumference. In a rotary atomizing head type coating machine configured to include a shaped air ejection member,
An annular flange member extending radially outward from an outer peripheral surface of the front portion is provided integrally or separately with the shaping air jet member at a front portion of the shaping air jet member. Rotating atomizing head type coating machine. The flange member is formed as a plate-like body having a flat front surface.
The rotary atomizing head type coating machine according to claim 1, wherein the front surface of the plate-like body is formed as the same surface as the front end of the shaping air ejection member. The flange member is formed as a cone whose inner peripheral surface is recessed into a concave cone,
2. The rotary atomizing head type coating machine according to claim 1, wherein the front end of the shaping air ejection member is located in the back of the inner peripheral surface of the cone.   2. The rotary atomizing head type coating machine according to claim 1, wherein a diameter dimension E (mm) of the flange member is D + 2 mm ≦ E ≦ D + 30 mm with respect to a diameter dimension D (mm) of the front end of the shaping air ejection member. .   The rotary atomizing head type coating machine according to claim 1, wherein a cylindrical cover member is provided at a position surrounding the air motor and the shaping air ejection member.   The rotary atomizing head type coating machine according to claim 5, wherein a purge air ejecting portion for ejecting purge air is provided on the outer peripheral side of the cover member from the rear side toward the front side along the outer peripheral surface of the cover member. .

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