Electricity remover

Abstract

It is possible to stabilize the distance between a prevention member and an electrode needle, which prevents the generation of induced voltage in a workpiece. In the static eliminator (1), the generation of induced voltage in a workpiece can be prevented by using a conductive plate (6) (front prevention member) of each of a plurality of needle cap members (3) provided on the front side (Df (+)) (in the needle tip direction) of an electrode needle (33). Furthermore, by providing a plurality of conductive plates (6), each conductive plate (6) can be formed short in the width direction (Dw). Therefore, deflection of the conductive plate (6) can be suppressed, and the distance between the conductive plate (6) and the electrode needle (33) can be stabilized.

Description

Technical Field

[0001] The present invention relates to a rod-shaped static eliminator that generates ions by applying a high voltage to a plurality of electrode needles arranged in a column along the arrangement direction. Background Art

[0002] The static eliminator uses ions generated by applying a high voltage to the electrode needles to statically charge a workpiece. At this time, due to the induced voltage generated in the workpiece, the balance between positive and negative ions may sometimes be disrupted. Therefore, in Patent Document 1, a plate-shaped conductive member that faces the electrode needles from the front side is provided to prevent the generation of the induced voltage.

[0003] Prior Art Documents

[0004] Patent Documents

[0005] Patent Document 1: Japanese Patent No. 6725938 Summary of the Invention

[0006] Problems to be Solved by the Invention

[0007] However, in a rod-shaped static eliminator in which a plurality of electrode needles are arranged in a column along the arrangement direction as in Patent Document 1, there are the following problems. That is, the rod-shaped static eliminator has a tendency to be long in the arrangement direction of the electrode needles. On the other hand, if the preventive member (the plate-shaped conductive member in Patent Document 1) for preventing the generation of the induced voltage is made long, there are the following problems: it takes time and effort to maintain the cleaning and replacement of the individual electrode needles; and the preventive member bends, and the distance between the electrode needle and the preventive member becomes unstable.

[0008] The present invention has been made in view of the above problems, and an object thereof is to provide a technique capable of stabilizing the distance between a preventive member for preventing the generation of an induced voltage in a workpiece and an electrode needle.

[0009] Means for Solving the Problems

[0010] The static eliminator of the present invention is a rod-shaped static eliminator that generates ions by applying a high voltage to a plurality of electrode needles arranged in a column along the arrangement direction, and includes: a frame that holds the plurality of electrode needles with their respective front ends facing the needle front end direction; a side preventive member that is provided on the frame, is located on the side of the electrode needles, and is electrically connected to the ground wire; and a plurality of front preventive members that are arranged in a column along the arrangement direction and are mounted on the frame, are located at a position closer to the needle front end direction than the electrode needles, and are electrically connected to the side preventive member.

[0011] In the present invention configured as described above, a plurality of front preventing members provided in the direction of the needle tip relative to the electrode needle can prevent the generation of induced voltage in the workpiece. Further, by providing a plurality of front preventing members, each front preventing member can be formed short. Therefore, flexure of the front preventing members can be suppressed, and the distance between the front preventing members and the electrode needle can be stabilized.

[0012] Advantages of the Invention

[0013] As described above, according to the present invention, it is possible to stabilize the distance between the preventing member that prevents the generation of induced voltage in the workpiece and the electrode needle. BRIEF DESCRIPTION OF THE DRAWINGS

[0014] Figure 1 FIG. is a perspective view showing the external structure of the rod-shaped static eliminator of the present invention.

[0015] Figure 2 FIG. is a front perspective view of the needle cap member.

[0016] Figure 3 FIG. is a rear perspective view of the needle cap member.

[0017] Figure 4 FIG. is an exploded perspective view of the needle cap member.

[0018] Figure 5 FIG. is a partial cross-sectional view of the needle cap member.

[0019] Figure 6 FIG. is a partial cross-sectional view of the needle cap member.

[0020] Figure 7 FIG. is a partial cross-sectional view of the needle cap member.

[0021] Figure 8 FIG. is a block diagram showing the electrical structure of the static eliminator.

[0022] Figure 9 FIG. is a block diagram showing the internal structure of the controller.

[0023] Figure 10 FIG. shows Figure 9 An example of the operation during ion balance control executed by the controller of.

[0024] Figure 11 FIG. is a perspective view showing the external structure of a modified example of the rod-shaped static eliminator of the present invention.

[0025] Figure 12 FIG. shows Figure 11 The internal structure of the static eliminator of.

[0026] Figure 13 FIG. shows Figure 11The perspective view of the cap unit included in the current eliminator.

[0027] Figure 14 It shows Figure 11 The perspective view of the cap unit included in the current eliminator.

[0028] Figure 15A It is a diagram showing the installation sequence of the cap unit on a pair of mounting plates.

[0029] Figure 15B It is a diagram showing the installation sequence of the cap unit on a pair of mounting plates.

[0030] Figure 15C It is a diagram showing the installation sequence of the cap unit on a pair of mounting plates. Detailed implementation mode

[0031] Figure 1 It is a perspective view showing the external structure of the rod-shaped current eliminator of the present invention. In this embodiment, the length direction Dl, width direction Dw, and air supply direction Df of the current eliminator 1 are shown. Here, the length direction Dl, width direction Dw, and air supply direction Df are orthogonal to each other. Moreover, the front side Df(+) and rear side Dd(-) of the air supply direction Df are shown. Here, the front side Df(+) and the rear side Dd(-) face opposite directions.

[0032] The current eliminator 1 has a long housing 2 in the length direction Dl. The housing 2 has: a base cover 21 that opens to the front side Df(+) of the air supply direction Df; a top cover 25 that is installed on the base cover 21 so as to cover the base cover 21 from the front side Df(+); and a pair of side covers 29 that are installed at both ends in the length direction Dl of the base cover 21 and the top cover 25. The base cover 21 and the top cover 25 each have a long shape in the length direction Dl.

[0033] The top cover 25 has a front plate 26 perpendicular to the air supply direction Df and a pair of side plates 27 extending rearward Dd(-) from both ends in the width direction Dw of the front plate 26, and there is an opening between the pair of side plates 27. The front plate 26 faces the base cover 21 from the front side Df(+), and the pair of side plates 27 sandwich the base cover 21 from the width direction Dw.

[0034] In addition, the current eliminator 1 has a plurality of pin cap members 3 arranged at a predetermined arrangement pitch in the length direction Dl on the front plate 26 of the top cover 25. Figure 2 It is the front perspective view of the pin cap member, Figure 3 It is the rear perspective view of the pin cap member, Figure 4 It is the exploded perspective view of the pin cap member, Figures 5 to 7 It is the partial cross-sectional view of the pin cap member.

[0035] The needle cap member 3 includes: a base portion 4; a front cover 5 that is attached to the base portion 4 from the front side Df(+); and a conductive plate 6 that is disposed between the base portion 4 and the front cover 5. The base portion 4 and the front cover 5 are made of resin.

[0036] Use Figure 5 Describe the structure of the flow path F through which air passes. The base portion 4 covers a through hole Hp extending along the air supply direction Df from the side (the longitudinal direction Dl and the width direction Dw). This through hole Hp constitutes the flow path F through which air toward the air supply direction Df passes. That is, the base portion 4 covers the flow path F through which air toward the air supply direction Df passes from the side.

[0037] The flow path F has a large-diameter flow path Fl provided at the end on the front side Df(+), a small-diameter flow path Fs provided at the end on the rear side Dd(-), and a tapered flow path Ft provided between the large-diameter flow path Fl and the small-diameter flow path Fs. With the central axis C of the needle cap member 3 parallel to the air supply direction Df as the center, the large-diameter flow path Fl, the tapered flow path Ft, and the small-diameter flow path Fs are arranged as concentric circles. The cross-sectional area of the large-diameter flow path Fl is larger than the cross-sectional areas of the small-diameter flow path Fs and the tapered flow path Ft respectively. In addition, the cross-sectional area of the tapered flow path Ft becomes larger as it faces the front side Df(+). The cross-sectional area of the end on the front side Df(+) of the tapered flow path Ft is smaller than the cross-sectional area of the large-diameter flow path Fl, and the cross-sectional area of the end on the rear side Dd(-) of the tapered flow path Ft is the same as the cross-sectional area of the small-diameter flow path Fs. Here, the cross-sectional area is the area of the cross-section on a plane orthogonal to the air supply direction Df.

[0038] The base portion 4 has a flange portion 41 having an octagonal outer shape when viewed from the air supply direction Df and a rod portion 45 extending rearward Dd(-) from the flange portion 41. The flange portion 41 protrudes laterally from the rod portion 45, and the rod portion 45 protrudes rearward Dd(-) from the center of the flange portion 41.

[0039] The flange portion 41 has a flange frame 411, and a front portion Hf of the through hole Hp in the air supply direction Df, that is, the through hole Hf, penetrates the flange frame 411 along the air supply direction Df. That is, the flange frame 411 surrounds the through hole Hf from the side. The flange frame 411 has a front end face 412 provided at the end on the front side Df(+) and a bottom face 413 provided on the rear side Dd(-) of the front end face 412. The front end face 412 and the bottom face 413 are planes perpendicular to the air supply direction Df respectively. When viewed from above from the front side Df(+), the front end face 412 surrounds the large-diameter flow path Fl from the side, and the bottom face 413 surrounds the tapered flow path Ft from the side.

[0040] The flange frame 411 has a wall surface 414 extending in the air supply direction Df between the inner circumference of the front end face 412 and the outer circumference of the bottom face 413. This wall surface 414 surrounds the large-diameter flow path Fl from the side. Moreover, the flange frame 411 has a conical wall surface 415 provided in a conical shape from the inner circumference of the bottom face 413 toward the rear side Dd(-). The cross-sectional area of the conical wall surface 415 becomes smaller toward the rear side Dd(-). This conical wall surface 415 is provided along the front end portion (the end portion on the front side Df(+)) of the conical flow path Ft and surrounds the front end portion of the conical flow path Ft from the side. Thus, the through hole Hf of the flange portion 41 includes the large-diameter flow path Fl and the front end portion of the conical flow path Ft.

[0041] In addition, a convex portion 416 and a concave portion 417 are provided at the end portion on the front side Df(+) of the flange frame 411. The convex portion 416 protrudes toward the front side Df(+), and the concave portion 417 is recessed toward the rear side Dd(-) with respect to the convex portion 416. The convex portion 416 and the concave portion 417 are alternately arranged around the central axis C of the needle cap member 3. Moreover, the flange portion 41 has a plurality (two) of screw insertion holes 418 provided in the flange frame 411 at equal angles around the central axis C of the needle cap member 3. Each screw insertion hole 418 penetrates the flange frame 411 in the air supply direction Df. In addition, the flange portion 41 is provided with two insertion ports A41( Figure 4 ) that penetrate the flange frame 411 in the air supply direction Df. The insertion ports A41 are provided to extend in the air supply direction Df between the end face 419 on the rear side Dd(-) of the flange frame 411 and the bottom face 413.

[0042] The rod portion 45 has a rod frame 451, and the rear side Dd(-) portion in the through hole Hp, that is, the through hole Hr, penetrates the rod frame 451 in the air supply direction Df. That is, the rod frame 451 surrounds the through hole Hr from the side. The rod frame 451 has a flange 452 protruding inward with respect to the through hole Hr, and when viewed from the air supply direction Df, the insertion port A452 opens inside the flange 452.

[0043] The rod frame 451 has a conical wall surface 453 provided at the end portion on the front side Df(+) and a wall surface 454 provided on the rear side Dd(-) of the conical wall surface 453. This conical wall surface 453 is provided along the rear end portion (the end portion on the rear side Dd(-)) of the conical flow path Ft and surrounds the rear end portion of the conical flow path Ft from the side. In addition, the wall surface 454 surrounds the small-diameter flow path Fs from the side. Thus, the through hole Hr of the rod portion 45 surrounds the rear end portion of the conical flow path Ft and the small-diameter flow path Fs from the side. In addition, the wall surface 454 extends to the rear side Dd(-) from the small-diameter flow path Fs, and a rounded corner is provided between the wall surface 454 and the front end face (the end face on the front side Df(+)) of the flange 452.

[0044] In addition, the rod frame 451 has a plurality (four) of engaging protrusions 458 that protrude outward (opposite side of the through-hole Hr). The plurality of engaging protrusions 458 are provided at regular angular intervals around the central axis C of the needle cap member 3.

[0045] The needle cap member 3 includes a flow path member 31 mounted on the flange 452 of the rod portion 45. The flow path member 31 has: a member main body 311 having a shape that tapers towards the front side Df(+); and a flange 312 that protrudes outward from the end portion of the rear side Dd(-) of the member main body 311. The member main body 311 is inserted into the insertion port A452 inside the flange 452 and engages with the flange 452. In addition, the flange 312 abuts against the end face of the rear side Dd(-) of the flange 452 from the rear side Dd(-).

[0046] In addition, the flow path member 31 has an insertion hole Hn that penetrates the member main body 311 and the flange 312 in the air supply direction Df. The insertion hole Hn has a tapered insertion hole Hnt provided at the end portion of the front side Df(+) and a cylindrical insertion hole Hnl provided on the rear side Dd(-) of the tapered insertion hole Hnt. The cross-sectional area of the tapered insertion hole Hnt decreases as it faces the front side Df(+). The cross-sectional area of the end portion on the rear side Dd(-) of the tapered insertion hole Hnt is the same as the cross-sectional area of the cylindrical insertion hole Hnl.

[0047] Moreover, the needle cap member 3 includes an electrode needle 33. The electrode needle 33 is inserted into the insertion hole Hn with the front end 331 of the electrode needle 33 facing the front side Df(+), and the front end 331 of the electrode needle 33 protrudes from the flow path member 31 towards the front side Df(+). The electrode needle 33 has a front end portion 332 that extends from the front end 331 towards the rear side Dd(-) and a cylindrical portion 333 that extends from the front end portion 332 towards the rear side Dd(-). The cross-sectional area of the front end portion 332 decreases as it faces the front side Df(+) (in other words, as it faces the front end 331). The cross-sectional area of the rear side Dd(-) of the front end portion 332 is the same as the cross-sectional area of the cylindrical portion 333.

[0048] Air in the air supply direction Df passes through the insertion hole Hn. That is, a gap that functions as a flow path f is formed between the inner wall of the insertion hole Hn of the flow path member 31 and the electrode needle 33 inserted into the insertion hole Hn, and the air passes through the flow path f in the air supply direction Df and is ejected from the front end (the end portion of the front side Df(+)) of the flow path member 31 towards the front side Df(+). In addition, a high voltage is applied to the electrode needle 33, and ions are generated from the electrode needle 33. These ions travel in the flow path F towards the front side Df(+) through the air ejected from the front end of the flow path member 31.

[0049] The front cover 5 has an opening 51 that overlaps with the flow path F when viewed from above the front side Df(+). Ions traveling forward in the flow path F reach the object to be neutralized (workpiece) through this opening 51 toward the front side Df(+). Further, the front cover 5 has an annular cover frame 52 that surrounds the opening 51 from the side when viewed from above. At the rear end Dd(-) of the cover frame 52, a convex portion 521 and a concave portion 522 are provided. The convex portion 521 protrudes toward the rear side Dd(-), and the concave portion 522 is recessed toward the front side Df(+) with respect to the convex portion 521. These convex portions 521 and concave portions 522 are alternately arranged around the central axis C of the needle cap member 3. And, on the cover frame 52, a plurality of screw covers 524 are provided at equal intervals around the central axis C of the needle cap member 3. On each screw cover 524, a screw insertion hole 525 extending along the air supply direction Df is provided, and the screw insertion hole 525 opens toward the rear side Dd(-).

[0050] The conductive plate 6 is made of a conductive material such as metal. An opening 61 that overlaps with the flow path F is provided in the conductive plate 6 when viewed from above the front side Df(+). Ions traveling forward in the flow path F pass through this opening 61 toward the front side Df(+) and then pass through the opening 51 of the front cover 5. When viewed from above the front side Df(+), the conductive plate 6 has an annular outer frame 62 that surrounds the opening 61 and an annular inner frame 63 provided at the center of the outer frame 62. The outer frame 62 and the inner frame 63 have circular shapes concentric with the central axis C of the needle cap member 3, and the diameter of the inner frame 63 is smaller than the diameter of the outer frame 62.

[0051] Inside the inner frame 63, an opening 64 that penetrates along the air supply direction Df functions as a flow path through which ions pass toward the front side Df(+). Further, when viewed from above the front side Df(+), the opening 64 of the inner frame 63 faces the front end 331 of the electrode needle 33. The opening 64 has a circular shape, and the diameter of the opening 64 is larger than the diameter of the electrode needle 33 (the diameter of the cylindrical portion 333). The electrode needle 33 is located at the center of the opening 64 inside the opening 64. This opening 64 functions as a maintenance opening for inserting a maintenance member such as a cotton swab for cleaning the front end 331 of the counter electrode needle 33.

[0052] Further, the conductive plate 6 has a plurality of connecting frames 65 that extend radially from the inner frame 63 to the outer frame 62. The plurality of connecting frames 65 are provided at equal angular intervals around the central axis C of the needle cap member 3, and the opening 66 between adjacent connecting frames 65 functions as a flow path through which ions pass toward the front side Df(+). Moreover, the conductive plate 6 has a plurality of (four) screw insertion holes 67 provided at equal angles around the central axis C of the needle cap member 3 in the outer frame 62. Each screw insertion hole 67 penetrates the outer frame 62 along the air supply direction Df.

[0053] Moreover, the needle cap member 3 has a leaf spring 35 made of a conductive material such as metal. The leaf spring 35 has a corrugated washer 351 (corrugated spring) in a corrugated ring shape, and an opening 352 is provided inside the corrugated washer 351. By inserting the rod portion 45 from the front side Df(+ ) into the opening 352, the leaf spring 35 is fitted into the rod portion 45 from the outside.

[0054] In addition, the leaf spring 35 has a plurality (two) of protrusions 353 provided at equal angles around the central axis C of the needle cap member 3. Each protrusion 353 protrudes from the corrugated washer 351 toward the front side Df(+). The protrusion 353 has an extension piece 354 extending from the corrugated washer 351 toward the front side Df(+), and an engagement piece 355 extending outward from the extension piece 354. Moreover, the leaf spring 35 has a plurality (two) of insertion holes 356 provided at equal angles around the central axis C of the needle cap member 3 in the corrugated washer 351. Each insertion hole 356 penetrates the corrugated washer 351 along the air supply direction Df.

[0055] The needle cap member 3 with the above structure is assembled in the following manner. The conductive plate 6 is fitted between the plurality of convex portions 521 of the front cover 5 and faces the opening 51 of the front cover 5 from the rear side Dd(-). Two screws 37 are inserted from the rear side Dd(-) into two of the four screw insertion holes 67 of the conductive plate 6. In addition, the two screws 37 are fastened from the rear side Dd(-) to two of the four screw insertion holes 525 provided in the front cover 5. In this way, the conductive plate 6 is fixed to the front cover 5.

[0056] In addition, with the conductive plate 6 sandwiched between the base portion 4 and the front cover 5, the base portion 4 is attached to the front cover 5 from the rear side Dd(-). That is, the convex portion 416 of the base portion 4 is fitted into the concave portion 522 of the front cover 5 from the rear side Dd(-), and the convex portion 521 of the front cover 5 is fitted into the concave portion 417 of the base portion 4 from the front side Df(+). Thereby, the base portion 4 and the front cover 5 are positioned relative to each other.

[0057] Moreover, the two protrusions 353 of the leaf spring 35 are inserted from the rear side Dd(-) into the two insertion ports A41 of the base portion 4, and the engagement pieces 355 of the respective protrusions 353 are engaged with the bottom surface 413 of the base portion 4. That is, the leaf spring 35 is attached to the base portion 4 by the engagement pieces 355.

[0058] The wave washer 351 of the leaf spring 35 contacts the base portion 4 from the rear side Dd(-). Then, two screws 38 are inserted into the two insertion holes 356 of the leaf spring 35 and the two screw insertion holes 418 of the base portion 4 from the rear side Dd(-), and are fastened to the two screw insertion holes 67 of the conductive plate 6 from the rear side Dd(-). At this time, the screws 38 are fastened to the conductive plate 6 while overcoming the elastic force generated by the wave washer 351 of the leaf spring 35 that contacts the base portion 4. In addition, the front ends of the two screws 38 are inserted into the two screw insertion holes 525 of the front cover 5 from the rear side Dd(-). The screws 38 are made of a conductive material such as metal and are in contact with the leaf spring 35 and the conductive plate 6 respectively. Thus, the leaf spring 35 and the conductive plate 6 are electrically connected and conduct electricity with each other.

[0059] As Figure 7 shown, the housing 2 is provided with a cap mounting opening A2 that opens in the air supply direction Df, and the needle cap member 3 is inserted into the cap mounting opening A2 from the front side Df(+). The front cover 5, the conductive plate 6, and the flange portion 41 of the base portion 4 are supported on the upper side of the housing 2 and are exposed. The rod portion 45 of the base portion 4 is housed in the housing 2, and a pair of base covers 21 of the housing 2 face the rod portion 45 in the width direction Dw.

[0060] A cap support member 11 is housed inside the housing 2. The cap support member 11 has a bottom plate 111 horizontally supported by the housing 2 and a cylindrical side wall 112 extending forward from the bottom plate 111 in the Df(+) direction. A rod insertion space 113 is provided inside the side wall 112. Moreover, the end portion of the rod portion 45 of the needle cap member 3 on the rear side Dd(-) is inserted into the rod insertion space 113 from the front side Df(+). In contrast, in the cap support member 11, a plurality (4) of protrusions 114 are provided at equal intervals around the central axis C of the needle cap member 3. Each protrusion 114 protrudes inward from the front end portion of the side wall 112 in the Df(+) direction. The plurality of protrusions 114 are provided corresponding to the plurality of engaging protrusions 458. Each protrusion 114 is located at a position in front of the corresponding engaging protrusion 458 in the Df(+) direction and overlaps the engaging protrusion 458 when viewed from above in the Df(+) direction. Thus, the rod portion 45 is prevented from coming out of the rod insertion space 113 in the Df(+) direction. In addition, by rotating the needle cap member 3 around the central axis C, the plurality of engaging protrusions 458 can be retracted from the plurality of protrusions 114 when viewed from above in the Df(+) direction. Thus, the rod portion 45 can come out of the rod insertion space 113 in the Df(+) direction, and the needle cap member 3 can be removed from the cap support member 11. That is, the needle cap member 3 is detachably mounted on the housing 2.

[0061] In addition, the electrical appliance 1 includes two grounding plates 13 (equivalent to Figure 1The side plates 27). The grounding plate 13 is provided on the surface of the housing 2. That is, the two grounding plates 13 face the electrode pins 33 from both sides in the width direction Dw. When viewed from the width direction Dw side, the grounding plate 13 overlaps the entire electrode pins 33. In other words, the electrode pins 33 are hidden by the grounding plate 13.

[0062] The grounding plate 13 is provided along the base cover 21 outside the base cover 21. In particular, the grounding plate 13 extends in the air supply direction Df from a front end position P(+) on the front side Df(+) that is closer to the front side Df(+) than the end portion (i.e., the front end 331) of the electrode pins 33 on the front side Df(+) to a rear end position P(-) on the rear side Dd(-) that is closer to the rear side Dd(-) than the end portion (i.e., the rear end 334) of the electrode pins 33 on the rear side Dd(-). The grounding plate 13 is made of a conductive material such as metal and is short-circuited to the ground wire. The end portion of the grounding plate 13 on the front side Df(+) contacts the leaf spring 35. In this way, the leaf spring 35 is short-circuited to the ground wire through the grounding plate 13.

[0063] Figure 8 is a block diagram showing the electrical structure of the de-energizer. As Figure 8 shown, the de-energizer 1 includes a high-voltage power supply circuit 16 that supplies a high voltage to the electrode pins 33 and a controller 17 that controls the high-voltage power supply circuit 16.

[0064] The high-voltage power supply circuit 16 has a switching circuit 161 and a high-voltage generating circuit 162. The switching circuit 161 turns on / off the power supply to the high-voltage generating circuit 162. The high-voltage generating circuit 162 has a primary boost circuit 163 and a secondary boost rectifier circuit 164. The primary boost circuit 163 boosts the voltage of the power supply supplied via the switching circuit 161, and the secondary boost rectifier circuit 164 boosts and rectifies the voltage output from the primary boost circuit 163 to generate a high voltage. The high voltage (negative-side drive voltage V2) generated by the secondary boost rectifier circuit 164 is applied to the electrode pins 33.

[0065] The high-voltage power supply circuit 16 has a switching circuit 165 and a high-voltage generating circuit 166. The switching circuit 165 turns on / off the power supply to the high-voltage generating circuit 166. The high-voltage generating circuit 166 has a primary boost circuit 167 and a secondary boost rectifier circuit 168. The primary boost circuit 167 boosts the voltage of the power supply supplied via the switching circuit 165, and the secondary boost rectifier circuit 168 boosts and rectifies the voltage output from the primary boost circuit 167 to generate a high voltage. The high voltage (positive-side drive voltage V1) generated by the primary boost circuit 167 is applied to the electrode pins 33 via the secondary boost rectifier circuit 164.

[0066] The controller 17 generates a PWM signal SWn for controlling the on / off of the power supply to the switch circuit 161 and a PWM signal SWp for controlling the on / off of the power supply to the switch circuit 165. The controller 17 generates the PWM signal SWn and the PWM signal SWp such that the negative-side drive voltage V2 and the positive-side drive voltage V1 are alternately applied to the electrode needle 33. The controller 17 is constituted by a processor, for example.

[0067] Figure 9 is a block diagram showing the internal structure of the controller. The controller 17 includes target value storage units 171, 174, an ion balance error extraction unit 172, an average potential calculation unit 173, an average potential error extraction unit 175, a drive control unit 176, a voltage value adjustment unit 177, an application time adjustment unit 178, and a PWM signal generation unit 179. The target value storage unit 171 holds the target value of the ion balance, and the target value storage unit 174 holds the target value of the average potential V0. These target values are set based on user operations, for example.

[0068] The ion balance error extraction unit 172 compares the detected value Vf of the ion balance with the corresponding target value, obtains the control error of the ion balance, and outputs it to the drive control unit 176. Specifically, the ion balance error extraction unit 172 obtains the detected value Vf by converting the charge flowing into the eliminator 1 through the grounded electrode into a voltage. The voltage value adjustment unit 177 adjusts the voltage value of the positive-side drive voltage V1 and the voltage value of the negative-side drive voltage V2 applied to the electrode needle 33 based on the control error of the ion balance. The average potential calculation unit 173 obtains a detected value Vn obtained by converting the current flowing from the transformer of the primary boost circuit 163 to the ground into a voltage and a detected value Vp obtained by converting the current flowing from the transformer of the primary boost circuit 167 to the ground into a voltage. Then, the average potential calculation unit 173 obtains the average potential V0 from the detected values Vn and Vp and outputs it to the average potential error extraction unit 175. The average potential V0 is obtained by V0 = Vp - Vn.

[0069] The average potential error extraction unit 175 compares the average potential V0 obtained by the average potential calculation unit 173 with the corresponding target value, obtains the control error of the average potential, and outputs it to the drive control unit 176. The application time adjustment unit 178 adjusts the application time Tp of the positive-side drive voltage V1 and the application time Tn of the negative-side drive voltage V2 based on the control error of the average potential.

[0070] The drive control unit 176 controls the adjustment amounts of the voltage values of the drive voltages V1 and V2 and the adjustment amounts of the application times Tp and Tn based on the control errors of the ion balance and the average potential. The PWM signal generation unit 179 generates the PWM signals SWp and SWn based on the outputs of the voltage value adjustment unit 177 and the application time adjustment unit 178.

[0071] Specifically, the duty ratio Ds = Tn / T1 for determining the application time and the respective duty ratios Dp = T12 / T11 of the PWM pulses Pp and Pn are set so that the ion balance and the average potential V0 are respectively consistent with the target values. At this time, the drive control unit 176 adjusts the duty ratios Ds and Dp so that the average potential V0 is kept constant.

[0072] Figure 10 It represents Figure 9 An example of the operation during the ion balance control executed by the controller. In Figure 10 it shows the process of adjusting the respective duty ratios Dp of the PWM pulses Pp and Pn based on the detected value of the ion balance.

[0073] In step S101, the controller 17 acquires the detected value Vf of the ion balance. In step S102, the controller 17 compares the detected value Vf with the target value. When Vf is greater than the target value (the case of "Yes" in step S103), the controller 17 increases the duty ratio Dp of the PWM pulse Pp and decreases the duty ratio Dp of the PWM pulse Pn in order to increase positive ions to eliminate the excess of negative ions (step S104). On the other hand, when Vf is less than the target value (the case of "Yes" in step S106), the controller 17 decreases the duty ratio Dp of the PWM pulse Pp and increases the duty ratio Dp of the PWM pulse Pn in order to increase negative ions to eliminate the excess of positive ions (step S107). The controller 17 repeatedly performs steps S101 to S104, S106, and S107 until Vf is consistent with the target value (step S105).

[0074] In the eliminator 1 configured in this way, by using the respective conductive plates 6 (front protection members) of the plurality of needle cap members 3 provided on the front side Df(+) (the direction of the needle tip) of the electrode needle 33, the generation of the induced voltage in the workpiece can be prevented. Moreover, by providing a plurality of conductive plates 6, each conductive plate 6 can be formed short in the width direction Dw. Therefore, when performing maintenance on a single electrode needle 33, the corresponding conductive plate 75 can be selectively loaded and unloaded. In addition, the flexure of the conductive plate 6 can be suppressed, and the distance between the conductive plate 6 and the electrode needle 33 can be stabilized.

[0075] In the eliminator 1 disclosed in the present embodiment, by disposing the conductive plate 6, the temporal change of the ion balance generated by reducing the operation frequency of the voltage application by the drive control unit 176 is reduced. This temporal change of the ion balance is called the swing voltage, and corresponds to the difference between the maximum value and the minimum value in one cycle of the drive period. Since this temporal change of the ion balance is generated according to the operation frequency, it is a change that may occur even if the ion balance is maintained constant by the control of the drive control unit 176. In the eliminator 1 disclosed in the present embodiment, by disposing the conductive plate 6, an experimental result that the swing voltage is reduced from 140 V to 2 V is obtained.

[0076] In addition, the conductive plate 6 is detachably attached to the housing 2 (frame) by the cap support 11. Thereby, it is possible to easily remove only the conductive plate 6 among the ground plate 13 (side prevention member) and the conductive plate 6.

[0077] In addition, a needle cap member 3 is provided. The needle cap member 3 holds the electrode needle 33 (first electrode needle) and the conductive plate 6 (first front prevention member), and is detachably attached to the housing 2 via the cap support 11. In this structure, the conductive plate 6 and the electrode needle 33 are positioned relative to each other by the needle cap member 3, and the distance between them can be stabilized.

[0078] In addition, in a state where the needle cap member 3 is attached to the housing 2 by the cap support 11, the end portion on the front side Df(+) of the ground plate 13 is located at a position on the front side Df(+) that is closer to the front end 331 of the electrode needle 33. Thus, the ground plate 13 covers the entire length of the electrode needle 33 from the side, and the electric field generated by the electrode needle 33 can be suppressed from spreading laterally.

[0079] In addition, the needle cap member 3 has a flow path member 31 that surrounds the electrode needle 33 from the side. The flow path f between the electrode needle 33 and the flow path member 31 has a reduced diameter shape in which the area of the flow path f becomes smaller toward the front side Df(+). By providing such a flow path member 31, a high-velocity airflow can be generated. Generally, as an index indicating the performance of the eliminator, there is an index such as the static elimination time for making the potential of a charged workpiece below a certain level. By disposing the conductive plate 6 on the front side Df(+) of the electrode needle 33, a part of the ions generated from the electrode needle 33 is absorbed by the conductive plate 6, so the ions reaching the workpiece are reduced and the static elimination time is shortened. In addition, if the flow velocity of the airflow caused by disposing the conductive plate 6 on the front side Df(+) is reduced, the ions reaching the workpiece per predetermined time are reduced, so the static elimination time is shortened. By generating a high-velocity airflow, it is possible to cope with the shortening of the static elimination time.

[0080] In addition, when viewed from the front side Df(+), the conductive plate 6 has an opening 64 (maintenance opening) opened at a position overlapping the electrode needle 33. The diameter of the opening 64 is larger than the diameter of the electrode needle 33. Therefore, maintenance can be easily performed on the electrode needle 33 using a maintenance member such as a cotton swab inserted from the opening 64.

[0081] In addition, the needle cap component 3 has a base portion 4 (resin component) that surrounds the flow path F provided from the electrode needle 33 to the front side Df (+) from the side. The flow path F surrounded by the base portion 4 has an expanded shape in which the area of ​​the flow path F increases toward the front side Df (+). By making the base portion 4 have an expanded shape in this way, it is possible to suppress the base portion 4 from being charged by ions passing through the flow path F.

[0082] In addition, an ion balance error extraction unit 172 (charge detection unit) is provided for detecting the amount of charge flowing from the grounded ground electrode into the static eliminator 1. And the controller 17 (control unit) controls the voltage applied to the electrode needle 33 based on the amount of charge detected by the ion balance error extraction unit 172. By using such ion balance control and the conductive plate 6 together, a good ion balance can be achieved.

[0083] Figure 11 1 is a perspective view showing the appearance structure of a modified example of the rod-type static eliminator of the present invention. Figure 12 Yes means Figure 11 A three-dimensional diagram of the internal structure of the static eliminator. Figure 13 and Figure 14 Yes means Figure 11 A three-dimensional view of a cap unit provided in a static eliminator. Figure 11 The static eliminator 7 has a housing 71 that is long in the width direction Dw. The housing 71 has a bottom frame 711 extending in the width direction Dw and a pair of side plates 712 provided at both ends of the bottom frame 711 in the length direction Dl. A plurality of electrode needles 33 arranged in the length direction Dl are built into the bottom frame 711, and the front end 331 of each electrode needle 33 faces the front side Df(+). In addition, in the bottom frame 711, as described above, a pair of butt plates 13 are opposite to the electrode needles 33 from both sides in the width direction Dw, and overlap with the entirety of the electrode needles 33 when viewed from the side in the width direction Dw.

[0084] In addition, the defroster 7 includes a pair of mounting plates 72 disposed at intervals in the width direction Dw. Each mounting plate 72 is made of a conductive material such as metal and is short-circuited to the ground wire. The pair of mounting plates 72 project forward (in the +Df direction) from the front-end portion of the bottom frame 711 in the front side Df(+) and are located at both ends in the width direction Dw of the bottom frame 711. The mounting plate 72 has a plurality of cutout portions 721 arranged along the length direction Dl. Each cutout portion 721 has an introduction groove 722 extending from the front-end portion (in the +Df direction) of the mounting plate 72 to the rear side Dd(-) along the air supply direction Df, and an engagement groove 723 extending from the rear-end portion (in the -Dd direction) of the introduction groove 722 to one side in the length direction Dl.

[0085] The defroster 7 has a plurality of cap units 73 arranged along the length direction Dl. Each cap unit 73 is mounted across the pair of mounting plates 72 in the width direction Dw and faces the bottom frame 711 from the front side Df(+). Each cap unit 73 is detachably mounted on the mounting plate 72.

[0086] The cap unit 73 has a unit frame 74. The unit frame 74 has a top cover 741 facing the bottom frame 711 from the front side Df(+). In the top cover 741, a plurality of (two in the Figure 13 example) openings 742 are arranged along the length direction Dl, and each opening 742 opens along the air supply direction Df. In addition, the unit frame 74 has a pair of side covers 743 extending from both ends in the width direction Dw of the top cover 741 to the rear side Dd(-). The pair of side covers 743 are provided corresponding to the pair of mounting plates 72, and each side cover 743 faces the corresponding mounting plate 72 from the outside in the width direction Dw. Moreover, the unit frame 74 has a plurality of engagement protrusions 744 arranged along the air supply direction Df. In the Figure 14 example, two engagement protrusions 744 are provided for one side cover 743. Each engagement protrusion 744 projects from the side cover 743 toward the inside in the width direction Dw (i.e., the mounting plate 72 side).

[0087] In addition, the cap unit 73 has a conductive plate 75 mounted on the unit frame 74. The conductive plate 75 is made of a conductive material such as metal and is short-circuited to the grounding plate 13. A plurality of (two in the Figure 13 example) openings 751 are arranged along the length direction Dl in the conductive plate 75. When viewed from above in the +Df direction, one opening 751 overlaps with one electrode pin 33 inside the bottom frame 711. Therefore, the ions generated by the electrode pin 33 ride on the air flow traveling forward (in the +Df direction) in the air supply direction Df and pass through the opening 751 forward (in the +Df direction). When viewed from above in the +Df direction, the conductive plate 75 has an annular outer frame 752 surrounding the opening 751 and an annular inner frame 753 provided at the center of the opening 751.

[0088] An opening 754 penetrating in the air supply direction Df is provided inside the inner frame 753. This opening 754 functions as a flow path through which ions pass forward (Df(+)). Further, when viewed from the front side Df(+), the opening 754 of the inner frame 753 faces the front end 331 of the electrode needle 33. The opening 754 is circular, and the diameter of the opening 754 is larger than the diameter of the electrode needle 33 (the diameter of the cylindrical portion 333). The electrode needle 33 is located at the center of the opening 754 inside the opening 754. This opening 754 functions as a maintenance opening for inserting a maintenance member such as a cotton swab for cleaning the front end 331 of the counter electrode needle 33.

[0089] Further, the conductive plate 75 has a plurality of connection frames 755 radially extending from the inner frame 753 to the outer frame 752. The plurality of connection frames 755 are provided at equal angular intervals around a center line passing through the center of the circular opening 751 and parallel to the air supply direction Df, and the opening 756 between adjacent connection frames 755 functions as a flow path through which ions pass forward (Df(+)).

[0090] Further, the cap unit 73 has a leaf spring 76 mounted on the rear side Dd(-) surface of the conductive plate 75. The leaf spring 76 is made of a conductive material such as metal. The center of the leaf spring 76 is held in contact with the conductive plate 75 by the spring holding portion 745 of the unit frame 74. Both ends of the leaf spring 76 are bent backward (Dd(-)) and separated from the conductive plate 75. In a state where the cap unit 73 is mounted on the pair of mounting plates 72, both ends of the leaf spring 76 are in contact with the mounting plates 72 and short-circuited to the ground wire. As a result, the conductive plate 75 is short-circuited to the ground wire via the leaf spring 76 and the mounting plates 72.

[0091] Figures 15A to 15C It is a diagram showing the mounting steps of mounting the cap unit on a pair of mounting plates. First, the engaging projection 744 of the cap unit 73 is opposed to the insertion groove 722 of the mounting plate 72 from the front side Df(+) ( Figure 15A ). Next, the engaging projection 744 of the cap unit 73 is inserted into the insertion groove 722 of the mounting plate 72 backward (Dd(-)) ( Figure 15B ). At this time, the engaging projection 744 is inserted into the insertion groove 722 against the elastic force generated by the leaf spring 76. Finally, the cap unit 73 is moved in the longitudinal direction Dl so that the engaging projection 744 of the cap unit 73 engages with the engaging groove 723 of the mounting plate 72 ( Figure 15C ). In this way, the mounting plate 72 is mounted on the pair of mounting plates 72. Further, by performing the opposite steps to these, the cap unit 73 can be removed from the pair of mounting plates 72.

[0092] In the eliminator 7 configured in this way, by means of the conductive plates 75 (front protection components) of the plurality of cap units 73 provided on the front side Df(+) (the needle tip direction) with respect to the electrode needles 33, the generation of induced voltage in the workpiece can be prevented. Moreover, by providing a plurality of conductive plates 75, each conductive plate 75 can be formed short in the length direction Dl. Therefore, when performing maintenance on a single electrode needle 33, the corresponding conductive plate 75 can be selectively loaded and unloaded. In addition, the flexure of the conductive plate 75 can be suppressed, and the distance between the conductive plate 75 and the electrode needle 33 can be stabilized.

[0093] In addition, the plurality of cap units 73 (the first unit, the second unit) are arranged along the length direction Dl. Each cap unit 73 has a conductive plate 75 located on the front side Df(+) of the plurality of electrode needles 33 (the first electrode needle, the second electrode needle, the third electrode needle, the fourth electrode needle). In a state where each cap unit 73 is mounted on a pair of mounting plates 72 (frames), the conductive plate 75 of each cap unit 73 is electrically connected to the mounting plate 72 (side protection component). Thus, it is configured to provide a plurality of conductive plates 75 with respect to one mounting plate 72 in the length direction Dl, and each conductive plate 75 can be shortened in the length direction Dl. Therefore, for example, in the usage environment of the eliminator 7 where the front side Df(+) faces downward, the flexure of the conductive plate 75 can be prevented, and the distance between the conductive plate 75 and the electrode needle 33 can be stabilized.

[0094] In addition, a notch portion 721 is provided on the mounting plate 72, and the cap unit 73 is mounted on the mounting plate 72 by engaging with the notch portion 721. Therefore, the cap unit 73 can be easily loaded and unloaded.

[0095] In addition, the present invention is not limited to the above-described embodiments, and various changes can be made to the above-described embodiments as long as the gist thereof is not deviated from. For example, the number of the electrode needles 33 can be appropriately changed.

[0096] In addition, the specific structure for loading and unloading the needle cap component 3 and the cap unit 73 is not limited to the above examples, and can be appropriately changed.

[0097] In addition, the number of the openings 751 provided in the conductive plate 75 is not limited to the above examples, and can be appropriately changed.

[0098] Industrial applicability

[0099] The present invention can be applied to the technology of all rod-type eliminators that apply a high voltage to a plurality of electrode needles arranged in a column along the arrangement direction to generate ions.

Claims

1. A rod-type static eliminator, which generates ions by applying a high voltage to a plurality of electrode needles arranged in a row along an arrangement direction, characterized in that: The static eliminator has: a frame for holding the plurality of electrode needles so that the front ends of the respective electrode needles face toward the needle front end direction; A side prevention component, which is arranged on the frame, located on the side of the electrode needle, and is connected to the ground wire; as well as A plurality of front prevention members are arranged in a row in the arrangement direction and mounted on the frame, are located closer to the needle tip direction than the electrode needles, and are electrically connected to the side prevention members.

2. The static eliminator according to claim 1, characterized in that: The front prevention member is detachably mounted on the frame.

3. The static eliminator according to claim 2, characterized in that: The static eliminator includes a needle cap member that holds a first electrode needle included in the plurality of electrode needles and a first front surface prevention member included in the plurality of front surface prevention members and is detachably mounted on the frame.

4. The static eliminator according to claim 3, characterized in that: When the needle cap member is attached to the frame, the end of the side prevention member in the needle tip direction is located closer to the needle tip direction than the tip of the first electrode needle.

5. The static eliminator according to claim 3, characterized in that: The needle cap member includes a flow path member that surrounds the first electrode needle from the side. The flow path between the first electrode needle and the flow path member has a reduced diameter shape in which the area of ​​the flow path decreases toward the needle tip.

6. The static eliminator according to claim 3, characterized in that: The front prevention member has a maintenance opening opened at a position overlapping with the first electrode needle when viewed from the needle front end direction. The maintenance opening has a diameter greater than a diameter of the first electrode needle.

7. The static eliminator according to claim 3, characterized in that: The needle cap member includes a resin member that surrounds the flow path provided from the first electrode needle toward the needle tip from the side. The flow path surrounded by the resin member has an expanding shape in which the area of ​​the flow path increases toward the needle tip.

8. The static eliminator according to claim 1, characterized in that: The static eliminator has: a first unit having a first front preventing member located in the needle front end direction of a first electrode needle and a second electrode needle among the plurality of electrode needles; and a second unit having a second front preventing member located in the needle front end direction of the third electrode needle and the fourth electrode needle among the plurality of electrode needles, In a state where the first unit and the second unit are mounted on the frame, the first front prevention member and the second front prevention member are in conduction with the side prevention member.

9. The static eliminator according to claim 8, characterized in that: The side prevention member is provided with a cutout portion, The first unit and the second unit are mounted on the frame by engaging with the cutout portion.

10. The static eliminator according to claim 1, characterized in that: The static eliminator includes a flow path member surrounding the electrode needle from the side. The flow path between the electrode needle and the flow path member has a reduced diameter shape in which the area of ​​the flow path decreases toward the tip of the needle.

11. The static eliminator according to any one of claims 1 to 10, characterized in that: The static eliminator has: a charge detection unit that detects the amount of charge flowing from the grounded ground electrode into the static eliminator; and A control section controls a voltage applied to the electrode needle based on the amount of charge detected by the charge detection section.

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