JPWO2019146681A1 - Vacuum suction arm, collet holder and nozzle collet - Google Patents

Abstract

A collet shaft 11 having a first tubular shape having a vacuum suction hole 31 continuous upward from the collet insertion hole 35 and having a guide hole penetrating from the outer circumference of the first tubular shape to the vacuum suction hole 31 and a collet. A tubular ball holding portion 17 having a sliding inner peripheral surface in contact with the shaft 11 and a tapered pressing inner peripheral surface extending from the sliding inner peripheral surface, and a tubular ball holding portion 17 arranged in a guide hole in a symmetrical direction from the pressing inner peripheral surface. Pressing balls 21a and 21b to be pressed and a nozzle having a second tubular shape whose upper shape matches the inner diameter shape of the collet insertion hole 35 and having a ring-shaped holding groove 41 on the outer peripheral surface of the second tubular shape. A collet 23 is provided. When the nozzle collet 23 is inserted into the collet insertion hole 35, the pressing balls 21a and 21b fitted in the holding groove 41 are pressed toward the holding groove 41 in symmetrical directions.

Description

The present invention relates to a vacuum suction arm used in a precision processing apparatus for handling fine members such as electronic parts and a collet holder constituting the vacuum suction arm, and particularly automatically automatically performs a nozzle collet inserted into the tip of the collet holder at high speed. Concerning collet holders and nozzle collets suitable for the system to be replaced.

As a conventional vacuum suction type precision processing device having a nozzle head, the pressure of a ring-shaped elastic body provided on the nozzle head side is transmitted to a pin roller embedded in a hole of the nozzle head, and the pin roller is transmitted to the side surface of the pipe of the device body. A mechanism has been proposed in which the device is fixed to the holding groove provided in (see Patent Document 1). A mechanism has also been proposed in which the pressure of an elastic body provided on the pipe side of the main body of the device is transmitted to a sphere installed in a hole of the pipe, and the sphere fits into a recess provided on the side surface of the nozzle head ( See Patent Document 2.). The inventions described in Patent Documents 1 and 2 are common in that the parts pressed by the elastic body provided on one member are fitted into the grooves of the other member and fixed, and the nozzle head By applying a force larger than the pressing force of the elastic body, both can be attached and detached with one touch.

Further, in the inventions described in Patent Documents 1 and 2, when there is a horizontal misalignment when fixing the nozzle head to the apparatus main body, a person visually confirms the degree of misalignment and manually corrects the position. It is not suitable for use in high precision high speed automatic replacement system of nozzle head because it has to be adjusted to. Alternatively, a device that recognizes the misalignment with a camera or a sensor and automatically adjusts it must be prepared separately. In the case of manual operation, it takes time and effort, and in the case of cameras and sensors, there is a problem that the cost for introducing the device is high.

A nozzle rotation prevention mechanism that prevents nozzle rotation by an asymmetric structure so that the nozzle mounting position does not shift with shaft rotation is also provided (see Patent Document 3). In the invention described in Patent Document 3, two hard balls are asymmetrically provided so as to be unevenly spaced from each other along the circumferential direction of the groove of the nozzle, and the two hard balls are formed in the groove of the groove of the nozzle. By fitting, the rotation of the nozzle is prevented. In the structure in which two hard balls are asymmetrically arranged as described in FIG. 1 (b) of Patent Document 3, the rotation of the nozzle can be prevented in a static state.

However, in the invention described in Patent Document 3, since the force from the two asymmetrically arranged hard balls is applied only in one direction, the high-speed vertical movement of the nozzle is performed in a dynamic operation such as nozzle replacement. Vertical shake occurs at this time, and the nozzle position is not stable when the nozzle is replaced. Therefore, in the invention described in Patent Document 3, vertical shake adversely affects the high-speed attachment / detachment of the nozzle, and the accuracy of the attachment / detachment of the nozzle in the high-speed vertical motion used in the high-precision high-speed automatic exchange system is improved. Can't keep high. Further, in the arrangement of the two asymmetrical hard balls described in Patent Document 3, the wear of the nozzle is biased, so that the life of the nozzle is extended in the case of high-speed vertical movement as used in a high-precision high-speed automatic exchange system. Shortened and inappropriate.

Japanese Patent No. 3087540 Japanese Patent No. 3064368 Japanese Unexamined Patent Publication No. 2003-243892

The present invention has been made by paying attention to the above problems, and can be used in a high-precision high-speed automatic replacement system for nozzle collets, and maintains high accuracy of suction / detachment of nozzle collets without vertical shake even in high-speed vertical movement. It is an object of the present invention to provide a vacuum suction arm capable of forming a vacuum suction arm, a highly accurate collet holder having a high holding force, and a nozzle collet inserted into the tip of the collet holder.

In order to achieve the above object, the first aspect of the present invention is (a) a first tubular shape having a vacuum suction hole continuous upward from the collet insertion hole at the lower end on the central axis side. Regarding the mirror image plane passing through the central axis, which penetrates from the outer circumference of the tubular shape of 1 to the vacuum suction hole, the first and second guide holes are provided so as to be perpendicular to the mirror image plane and facing each other on the center line passing through the central axis. The collet shaft, (b) the sliding inner peripheral surface in contact with the outer peripheral surface of the collet shaft, the tapered pressing inner peripheral surface extending downward from the sliding inner peripheral surface and in the centrifugal direction from the central axis, and the pressing inner peripheral surface. A tubular ball holding portion that has a protective inner peripheral surface that is continuous downward from the center and is slidable in the central axis direction, and (c) are arranged in the first and second guide holes, respectively, from the pressing inner peripheral surface. It has first and second pressing balls that can be pressed symmetrically, and (d) a through hole that is continuous upward in the central axis direction from the nozzle tip insertion hole provided at the lower end, and is the upper part. A vacuum suction arm having a second tubular shape whose outer diameter shape matches the inner diameter shape of the collet insertion hole, and a nozzle collet having a ring-shaped holding groove on the outer peripheral surface of the second tubular shape. The gist is that. In the vacuum suction arm according to the first aspect, when the upper portion of the nozzle collet is inserted into the collet insertion hole, the first and second pressing balls fitted in the holding groove are pressed toward the holding groove in symmetrical directions. To do.

A second aspect of the present invention is (a) a first tubular shape having a vacuum suction hole continuous upward from the collet insertion hole at the lower end on the central axis side, and a vacuum is formed from the outer circumference of the first tubular shape. A collet shaft provided with first and second guide holes that are perpendicular to the mirror image plane and face each other on the center line passing through the central axis in a mirror image relationship with respect to the mirror image plane that penetrates to the suction hole and passes through the central axis, and (b). A sliding inner peripheral surface in contact with the outer peripheral surface of the collet shaft, a tapered pressing inner peripheral surface that extends downward from the sliding inner peripheral surface and in the centrifugal direction from the central axis, and a protective inner peripheral surface that is continuous downward from the pressing inner peripheral surface. A tubular ball holding portion having a surface and slidable in the central axis direction, and (c) being arranged in the first and second guide holes, respectively, and being pressed symmetrically from the pressing inner peripheral surface. The gist is that it is a collet holder provided with possible first and second pressing balls. The collet holder according to the second aspect has a through hole that is continuous upward in the central axis direction from the nozzle tip insertion hole provided at the lower end portion, and the outer diameter shape of the upper portion is the inner diameter shape of the collet insertion hole. When the upper part of the nozzle collet having a matched second tubular shape and provided with a ring-shaped holding groove on the outer peripheral surface of the second tubular shape was inserted into the collet insertion hole, it was fitted into the holding groove. The first and second pressing balls are pressed toward the holding groove in symmetrical directions.

A third aspect of the present invention has a through hole that is continuous upward in the central axis direction from the nozzle tip insertion hole provided at the lower end portion, and the outer diameter shape of the upper portion is the collet insertion hole at the lower end of the collet holder. The present invention relates to a nozzle collet having a second tubular shape that matches the inner diameter shape of the nozzle collet, and a ring-shaped holding groove is provided on the outer peripheral surface of the second tubular shape. In the nozzle collet according to the third aspect, the collet holder forms a first tubular shape having a vacuum suction hole continuous upward from the collet insertion hole on the central axis side, and vacuum suction is performed from the outer circumference of the first tubular shape. A collet shaft having first and second guide holes facing each other on the center line perpendicular to the mirror image plane and passing through the central axis in a mirror image relationship with respect to the mirror image plane penetrating to the hole and passing through the central axis, and the outer circumference of the collet shaft. It has a sliding inner peripheral surface in contact with the surface, a tapered pressing inner peripheral surface that extends downward from the sliding inner peripheral surface and in the centrifugal direction from the central axis, and a protective inner peripheral surface that is continuous downward from the pressing inner peripheral surface. A tubular ball holding portion that can slide in the central axis direction and a first and second pressing that are arranged in the first and second guide holes and can be pressed symmetrically from the inner peripheral surface of the pressing. Equipped with a sphere. Then, in the nozzle collet according to the third aspect, when the upper portion of the nozzle collet is inserted into the collet insertion hole, the first and second pressing balls fitted in the holding groove are directed toward the holding groove in symmetrical directions. Press.

According to the present invention, a vacuum suction arm that can be used in a high-precision high-speed automatic replacement system for a nozzle collet and can maintain high accuracy of suction / detachment of a nozzle collet without vertical shaking even in high-speed vertical movement, this vacuum suction arm. It is possible to provide a highly accurate collet holder having a high holding force and a nozzle collet inserted into the tip of the collet holder.

FIG. 1A is a front view of the vacuum suction arm according to the embodiment of the present invention, FIG. 1B is a cross-sectional view taken from the direction AA of FIG. 1A, and FIG. 1C. ) Is an enlarged view of a portion A in FIG. 1 (b). FIG. 2A is a front view when the nozzle tip is inserted into the vacuum suction arm according to the embodiment of the present invention, and FIG. 2B is a cross-sectional view taken from the direction AA of FIG. 2A. Is. FIG. 3A is a cross-sectional perspective view of the nozzle tip of FIG. 2B, and FIG. 3B is a perspective view of the nozzle tip as viewed from below. 2 is a cross-sectional view of the nozzle collet and the nozzle tip removed from the collet holder of the vacuum suction arm according to the embodiment of the present invention from the state of FIG. 2B. 5 (a) is a front view when the ball holding portion slides upward from the state of FIG. 1 (a), and FIG. 5 (b) is a cross section seen from the direction AA of FIG. 5 (a). FIG. 5 (c) is an enlarged view of a portion A of FIG. 5 (b). 6 (a), (b), and (c) are views corresponding to the enlarged view of the A portion of FIG. 1 (b), and FIG. 6 (a) is a view before the nozzle collet is removed, and FIG. (B) is a transition diagram during the removal of the nozzle collet, and FIG. 6 (c) is a diagram after the nozzle collet is removed. FIG. 7A is an enlarged cross-sectional view seen from the direction BB of FIG. 1A, and FIG. 7B is a view corresponding to FIG. 7A when there are four pressing balls. .. FIG. 8A is a front view of the entire precision processing apparatus provided with the vacuum suction arm according to the embodiment of the present invention, and FIG. 8B shows the nozzle collet and the nozzle tip from the state of FIG. 8A. It is sectional drawing of the removed state. It is a perspective view of FIG. 8A. FIG. 7 is an enlarged cross-sectional view of a vacuum suction arm according to a comparative example corresponding to FIG. 7, where FIG. 10A shows a case where there are three pressing balls and FIG. 10B shows a case where there is one pressing ball. It is a figure.

Hereinafter, embodiments of the present invention will be described with reference to the drawings. In the description of the drawings below, the same or similar parts are designated by the same or similar reference numerals. However, it should be noted that the drawings are schematic, and the relationship between the thickness and the plane dimensions, the ratio of the sizes of each member, etc. are different from the actual ones. Therefore, the specific thickness, dimensions, size, etc. should be judged more diversely in consideration of the purpose of the technical idea that can be understood from the following explanation. In addition, it goes without saying that the drawings include parts having different dimensional relationships and ratios from each other.

Further, the embodiments of the present invention shown below exemplify an apparatus for embodying the technical idea of the present invention, and the technical idea of the present invention describes the material, shape, structure, and the like of the constituent parts. The arrangement etc. is not specified to the following. The technical idea of the present invention is not limited to the contents described in the embodiments of the present invention, and various modifications can be made within the technical scope specified by the claims described in the claims. ..

(Vacuum suction arm structure)
The vacuum suction arm according to the embodiment of the present invention constitutes a part of a vacuum suction type precision processing apparatus for assembling and mounting an electronic component or the like as an object to be operated, as shown in FIGS. 8 and 9. As shown in FIG. 1, the vacuum suction arm according to the embodiment has a tubular collet shaft 11, a spring pressing portion 13 fixed to the collet shaft 11, and an upper end portion in contact with the spring pressing portion 13, and the collet shaft 11 A spring 15 that can be expanded and contracted in the tubular axis direction, a tubular ball holding portion 17 that is in contact with the collet shaft 11 and can slide in the tubular axis direction of the collet shaft 11 while expanding and contracting the spring 15, and a guide for the collet shaft 11. A collet holder (11, 13, 15, 17, 21a, 21b) is provided with a first pressing ball 21a and a second pressing ball 21b arranged in the hole. As shown in the cross-sectional views of FIGS. 1B and 7A, in the vacuum suction arm according to the embodiment, the first pressing ball 21a and the second pressing ball 21b form a tubular shaft of the collet shaft 11. They are arranged so as to face each other on a line passing through the tubular axis of the collet shaft 11 so as to have a mirror image relationship with respect to the mirror image surface passing through. As will be described later, in order to achieve a mirror image relationship with respect to the surface of the collet shaft 11 passing through the cylinder axis (central axis), it is desirable that the number of pressing balls is an even number. In the arrangement shown in FIG. 7A, the first pressing ball 21a and the second pressing ball 21b are aligned on a center line perpendicular to the mirror image plane passing through the cylinder axis of the collet shaft 11.

Further, as shown in FIG. 4, the collet shaft 11 has an upper portion inside the collet holder (11, 13, 15, 17, 21a, 21b) of the vacuum suction arm according to the embodiment on the lower end side of the collet shaft 11. Nozzle head unit (23, 25) including a nozzle collet 23 that can be inserted and removed from the lower end of the nozzle collet 23, a detent pin 25 fixed to the outer peripheral surface of the nozzle collet 23, and a nozzle tip 51 inserted from the lower end side of the nozzle collet 23. , 51) is inserted.

That is, as shown in FIGS. 2 and 8, the lower end of the collet holder (11, 13, 15, 17, 21a, 21b) according to the embodiment has a conical shape of the nozzle head unit (23, 25, 51). The upper part of is insertable. In the embodiment (direction) shown in FIGS. 1, 2, 4, 4 and the like, the collet holders (11, 13, 15, 17, 21a, 21b) of the vacuum suction arm according to the embodiment have the vertical direction as the longitudinal direction. Is provided with a collet shaft 11. As shown in FIG. 4, the collet shaft 11 has a first tubular shape that defines the first outer peripheral surface, and the collet insertion hole 35 at the lower end in the longitudinal direction and the collet insertion hole 35 to the first tubular shaft. It has a continuous vacuum suction hole 31 above the direction (first direction).

As shown in FIG. 8, the upper end of the vacuum suction hole 31 is connected to the vacuum piping joint (adapter) 71. With the nozzle head unit (23, 25, 51) inserted in the lower end of the collet shaft 11, air is sucked by the vacuum pump through the vacuum piping joint (adapter) 71 shown in FIGS. 8 and 9. A vacuum suction chuck is configured in which the collet shaft 11, the nozzle collet 23, and the cavity inside the nozzle tip 51 are under negative pressure, and the object to be operated is evacuated (vacuum suction) at the tip of the nozzle tip 51. .. When the cavity inside the collet shaft 11, the nozzle collet 23, and the nozzle tip 51 is set to positive pressure while the object to be evacuated is vacuum-sucked, the object to be evacuated is the tip of the nozzle tip 51. Detach from.

As shown in the enlarged views of FIGS. 1 (c), 5 (c), 6 (a), etc., a notch-shaped detent groove 45 is provided at the outer edge of the lower end of the collet shaft 11 to rotate the collet shaft 11. Above the stop groove 45, a guide hole (first guide hole) 43a that penetrates from the first outer peripheral surface of the collet shaft 11 in the centripetal direction is provided. The "first outer peripheral surface" refers to the entire outer side surface of the first tubular shape of the collet shaft 11. The collet insertion hole 35 and the vacuum suction hole 31 are continuous along the first direction which is the longitudinal direction, and penetrate almost the entire collet shaft 11 along the first direction. In FIG. 1B, the diameter of the collet insertion hole 35 is larger than the diameter of the vacuum suction hole 31, but if the upper part of the nozzle collet 23 can be inserted and removed, the diameter of the collet insertion hole 35 is the diameter of the vacuum suction hole 31. It can be smaller. As shown in FIG. 4, the upper portion of the nozzle collet 23 has a stepped portion, but the envelope surface connecting the corner portions of the stepped portion has an outer diameter surface having a substantially conical shape. At the boundary between the collet insertion hole 35 and the vacuum suction hole 31 shown in FIG. 1B, an elastic body such as an O-ring is provided to prevent air leakage or to cushion the impact when the nozzle collet 23 is inserted. It may or may not be provided.

Further, as shown in FIGS. 1A and 1B, the collet holders (11, 13, 15, 17, 21a, 21b) according to the embodiment are springs fixed to the first outer peripheral surface of the collet shaft 11. A holding portion 13 is provided. The method of fixing the spring holding portion 13 to the collet shaft 11 may be metal joining such as welding or brazing, joining using pressure deformation such as shrink fitting or caulking, press fitting, mechanical joining using screws or the like. , Chemical bonding with an adhesive or the like may be used. Since the spring pressing portion 13 is a member that is in contact with the upper end portion of the spring 15 and does not move by the pressing of the spring 15, any fixing method that can withstand the pressing of the spring 15 may be used. In FIG. 1B, the spring pressing portion 13 is a member different from the collet shaft 11, but the spring pressing portion 13 may have a structure integrated with the collet shaft 11. Further, in FIG. 1B, the spring pressing portion 13 has a stepped shape having a sheath portion protruding in a cylindrical shape on the lower side so that the cross-sectional shape is L-shaped. By sandwiching the sheath portion of the spring holding portion 13 between the spring 15 and the collet shaft 11 in a cylindrical shape, the spring 15 is prevented from coming into direct contact with the collet shaft 11. The sheath portion of the spring pressing portion 13 has a preferable structure because it has an effect of reducing friction and preventing deterioration of the member by reducing the contact area of the spring 15 with the collet shaft 11. However, since it is sufficient that the spring 15 is between the spring pressing portion 13 and the ball pressing portion 17 and can play a role of sliding the ball pressing portion 17 slidable in the first direction, the lower portion of the spring pressing portion 13 is required. There may or may not be a sheath protruding to the side.

The spring 15 may be any one having a function as a spring, such as a coil spring or a ring spring whose central axis coincides with the central axis of the vacuum suction hole 31, and an aggregate of coil springs whose side surface portions are in contact with the spring holding portion 13. Can be used. The upper end portion of the spring 15 is in contact with the spring pressing portion 13, but if the function of the spring 15 as a spring is not lost, the upper end portion may be fixed to the spring pressing portion 13.

Further, as shown in FIG. 1, the collet holder (11, 13, 15, 17, 21a, 21b) according to the embodiment has a tubular ball holding portion 17 in contact with the lower end portion of the spring 15 of the collet shaft 11. Provided on the first outer peripheral surface side. The ball holding portion 17 has, as an inner peripheral surface, a sliding inner peripheral surface in contact with the first outer peripheral surface between the spring holding portion 13 and the first guide hole 43a, and a vacuum suction hole 31 below the sliding inner peripheral surface. It has a tapered pressing inner peripheral surface 19 continuous from the central axis in the centrifugal direction, and a protective inner peripheral surface continuous downward from the pressing inner peripheral surface 19. Although the sliding inner peripheral surface is in contact with the first outer peripheral surface, it is not fixed and can rotate and slide. The pressing inner peripheral surface 19 is a conical inner peripheral surface that is continuous in a divergent shape below the sliding inner peripheral surface. The protective inner peripheral surface is provided as a cylindrical surface that is continuous with the pressing inner peripheral surface 19 and whose bus direction is parallel to the first direction. The diameter of the cylindrical space surrounded by the protective inner peripheral surface is larger than the diameter of the cylindrical space surrounded by the sliding inner peripheral surface.

Further, the ball holding portion 17 has a sliding inner peripheral surface as a common surface, and a stepped portion from a thick flange portion in the center so that the cross-sectional shape of the upper portion in the longitudinal direction is substantially L-shaped on the outer peripheral surface side. It has a cylindrical shape. The ball holding portion 17 has a cylindrical sheath portion extending upward in the longitudinal direction from the central flange portion, and the outer peripheral surface of the sheath portion is in contact with the inner peripheral side of the lower end portion of the spring. This sheath portion prevents the spring 15 from coming into direct contact with the collet shaft 11 as in the case of the spring pressing portion 13. By reducing the contact area of the spring 15 with the collet shaft 11, friction is reduced and deterioration of the member is prevented, which is a preferable structure. However, since the spring 15 is located between the spring pressing portion 13 and the ball pressing portion 17 and can play a role of sliding the ball pressing portion 17 slidable in the first direction, this sheath portion is present. It may not be. As in the case of the spring pressing portion 13, the lower end portion of the spring 15 may be fixed to the ball pressing portion 17 as long as the function of the spring 15 as a spring is not lost. In FIG. 1B, a gap 33 exists between the spring pressing portion 13 and the ball pressing portion 17, and the gap 33 is an upward slidable region of the ball pressing portion 17. The gap 33 also has the effect of reducing the contact area of the spring 15 and reducing the friction when the spring 15 expands and contracts. The ball holding portion 17 can slide in the first direction on the first outer peripheral surface of the collet shaft 11 as the spring 15 expands and contracts.

Further, as shown in FIGS. 1 (b) and 1 (c), the collet holders (11, 13, 15, 17, 21a, 21b) according to the embodiment are arranged in the first guide hole 43a, and the pressing inner circumference is formed. A pressing ball (first pressing ball) 21a capable of being pressed by the spring 15 via the surface 19 and moving in a direction substantially perpendicular to the first direction is provided. The first pressing ball 21a is not directly fixed to the first guide hole 43a. The second pressing ball 21b in FIG. 1B is the same as the first pressing ball 21a, and the second pressing ball 21b is a mirror image of the surface passing through the first pressing ball 21a and the cylinder axis (central axis) of the collet shaft 11. They are arranged so that they are in a relationship. The second pressing ball 21b is arranged in the second guide hole provided in the collet shaft 11, is pressed by the spring 15 via the pressing inner peripheral surface 19, and can move in a direction substantially perpendicular to the first direction. it can.

Further, as shown in FIGS. 1 (b), 2 (b), and 4, the vacuum suction arm according to the embodiment has a collet insertion hole 35 of a collet holder (11, 13, 15, 17, 21a, 21b). A nozzle collet 23 that can be inserted into and removed from the vacuum tube is provided. The upper end portion of the nozzle collet 23 has a conical shape with a small upper bottom, and has an outer diameter dimension that matches the inner diameter shape of the collet insertion hole 35. When the upper part of the nozzle collet 23 is inserted into the collet insertion hole 35, the tip portion of the nozzle collet 23 presses in a symmetrical direction by the spring 15 via the first pressing ball 21a and the second pressing ball 21b. Receives in the direction of the cylinder axis (central axis) of 11.

As shown in FIG. 1 (b), the lower portion of the nozzle collet 23 has a collet shape (cylindrical clamp shape) in which a nozzle tip insertion hole 39 is provided at the lower end portion thereof. A through hole 37 continuous above the nozzle tip insertion hole 39 in the first direction is provided, and has a second tubular shape defined by a second outer peripheral surface so that the tip portion has a truncated cone shape. The size and shape of the nozzle tip insertion hole 39 does not matter as long as the nozzle tip can be inserted and clamped. Since the shape of the nozzle tip differs depending on the object to be operated, the nozzle tip insertion hole 39 needs to match the shape of the nozzle tip.

The “second outer peripheral surface” of the nozzle collet 23 refers to the entire outer side surface of the second tubular shape, and has a plurality of irregularities as shown in FIGS. 1 (b) and 4 and the like, but the envelope surface is generally conical. It is a shaped surface. The nozzle collet 23 is provided with a ring-shaped holding groove 41 on the second outer peripheral surface, and when the upper portion of the nozzle collet 23 is inserted into the collet insertion hole 35, the first pressing ball 21a moves and the first pressing ball The holding groove 41 receives the pressure of the spring 15 through the fitting of the 21a into the holding groove 41. Regarding the second pressing ball 21b arranged so as to have a mirror image relationship with respect to the surface passing through the cylinder axis (central axis) of the first pressing ball 21a and the collet shaft 11, the movement of the second pressing ball 21b and the second pressing ball 21b Is pressed into the holding groove 41 by the spring 15 in the holding groove 41 in a symmetrical direction having a mirror image relationship with the first pressing ball 21a. The holding groove 41 is a ring-shaped groove that surrounds the upper part of the second outer peripheral surface, and may be positioned so as to fit in the collet insertion hole 35 when the nozzle collet 23 is inserted into the collet insertion hole 35. Further, the shape of the holding groove 41 is V-shaped in the cross-sectional views of FIGS. 1B and 1C, but the shape is not limited to the V-shaped cross-sectional shape. The cross-sectional shape of the holding groove 41 cut in the longitudinal direction along the first direction is such that when the nozzle collet 23 is inserted into the collet insertion hole 35, the first cylinder is pressed via the inner peripheral surface 19 pressed by the spring 15. As long as the first pressing ball 21a and the second pressing ball 21b pushed in the centripetal direction can be fitted, it may be U-shaped or U-shaped.

Further, as shown in FIGS. 1 (b) and 1 (c) and FIG. 4, the detent pin 25 is fixed to the second outer peripheral surface of the nozzle collet 23 according to the embodiment. The detent pin 25 fits into the detent groove 45 of the vacuum suction arm when the upper portion of the nozzle collet 23 is inserted into the collet insertion hole 35. The detent pin 25 is a pin fixed so as to protrude in the centrifugal direction from the central axis of the through hole 37 of the nozzle collet 23 from the second outer peripheral surface. When the nozzle collet 23 is inserted into the collet insertion hole 35, it is fitted into the notch-shaped detent groove 45 so that the nozzle tip is inserted with the position (rotation angle) in the rotation direction of the nozzle tip with respect to the central axis of the through hole 37. It has a function to determine the depth. As long as it has the same function, the detent pin 25 may have a structure integrated with the nozzle collet 23. In FIGS. 1B and 1C, the detent groove 45 is located below the first guide hole 43a, but the position and insertion depth of the nozzle collet 23 in the rotational direction with respect to the central axis of the through hole 37 can be determined. The position of the detent groove 45 is arbitrary as long as it has a function of determining.

As shown in FIG. 3, the nozzle tip 51 inserted into the nozzle collet 23 used for the vacuum suction arm according to the embodiment has a shape of a lower end having a suction window 49 having a side length of, for example, about 0.1 mm. It is a fine rectangle of the following, or about 0.05 mm or less. It is important for vacuum suction of an object to be operated having a minute dimension such that the direction of each side of this rectangular portion is about 0.1 mm or less or about 0.05 mm or less. If the position of the nozzle tip 51 in the rotational direction with respect to the nozzle collet 23 can be appropriately adjusted in the state shown in FIG. 4, when the nozzle collet 23 is in the state shown in FIG. 2 inserted into the collet insertion hole 35, The direction of the rectangular portion at the tip of the nozzle tip 51 can be arranged at the correct position (angle) with respect to the central axis of the through hole 37.

(One-touch operation)
The action of one-touch pressing by the spring 15 in a state where the nozzle collet 23 is inserted into the collet insertion holes 35 of the collet holders (11, 13, 15, 17, 21a, 21b) using FIGS. 1 and 5. Will be explained in detail.

In FIGS. 1A and 1B, the pressure in the symmetrical direction by the stretchable spring 15 is applied in the direction in which the ball holding portion 17 slidable in the first direction is slid downward. In FIG. 1C, the pressure applied to the ball holding portion 17 is transmitted to the first pressing ball 21a and the second pressing ball 21b in contact with the pressing inner peripheral surface 19. Since the first pressing ball 21a is arranged without being fixed to the first guide hole 43a, the pressing is transmitted in the direction orthogonal to the first direction (centripetal direction). Although not shown, the second pressing ball 21b is also fixed to the second guide hole arranged so as to have a mirror image relationship with the first guide hole 43a with respect to the surface of the collet shaft 11 passing through the tubular shaft (central axis). In the direction orthogonal to the first direction (centripetal direction), the pressure is transmitted in the direction that is in a mirror image relationship with the first pressing ball 21a. In the state where the nozzle collet 23 is inserted into the collet insertion hole 35 as shown in FIG. 1 (c), the pressure transmitted symmetrically to the first pressing ball 21a and the second pressing ball 21b is the holding groove of the nozzle collet 23. It is called 41. The downward pressing of the spring 15 is converted into a symmetrical pressing in a direction close to the horizontal direction (centric direction toward the center of the first tubular shape) by the intervention of the pressing inner peripheral surface 19, and the nozzle collet. 23 is temporarily held (fixed) to the collet shaft 11.

In order to realize the fixing of the nozzle collet 23 to the collet shaft 11 by the symmetrical pressing forming the mirror image relationship, the shape of the first guide hole 43a is directed from the first outer peripheral surface to the center of the first tubular shape. A shape that narrows in the centripetal direction is preferable. The lower surface of the first guide hole 43a may be horizontal and the upper surface may be tapered. Both the upper surface and the lower surface of the first guide hole 43a may be horizontal, and both side surfaces of the first guide hole 43a may be tapered when viewed in a cross-sectional view from above as shown in FIG. In any case, as shown in FIG. 1C, the first pressing ball 21a and the second pressing ball 21b have a shape in which the symmetrical pressing applied from the pressing inner peripheral surface 19 is transmitted to the holding groove 41. All you need is. The first guide hole 43a and the pressing inner peripheral surface 19 are linear in the cross-sectional view of FIG. 1 (c), but may have a curved shape when viewed in the cross-sectional view. Although not shown, the second guide hole and the pressing inner peripheral surface 19 of the second pressing sphere 21b, which has a mirror image relationship with the first pressing sphere 21a, have a curved shape when viewed in a cross-sectional view. However, symmetry is required so as to form a mirror image relationship with the first guide hole 43a.

FIG. 5 shows a state in which the ball holding portion 17 in FIG. 1 is slid upward and the sheath portion of the ball holding portion 17 is in contact with the sheath portion of the spring pressing portion 13, that is, a state in which the gap 33 in FIG. 1 is eliminated. .. In the state of FIG. 5, since the pressing inner peripheral surface 19 does not contact the first pressing ball 21a and the second pressing ball 21b, the pressing of the spring 15 is not transmitted to the first pressing ball 21a and the second pressing ball 21b. If the lower surface of the first guide hole 43a is tapered as shown in FIG. 5C, the first pressing ball 21a and the second pressing ball 21b move in the centrifugal direction from the center of the first tubular shape. .. The first pressing ball 21a and the second pressing ball 21b have a structure that does not come off from the vacuum suction arm according to the embodiment by being pressed by the protective inner peripheral surface even if they move so as to protrude greatly from the first outer peripheral surface. It has become. The movement of the first pressing ball 21a and the second pressing ball 21b disengages the fitting from the holding groove 41, the nozzle collet 23 is not pressed, and the nozzle collet 23 is disengaged from being fixed to the collet shaft 11. Even if the lower surface of the first guide hole 43a is not tapered, the first pressing ball 21a and the second pressing ball 21b do not press the holding groove 41, and the nozzle collet 23 is disengaged from being fixed to the collet shaft 11. Become.

The state of removing the nozzle collet 23 from the collet holders (11, 13, 15, 17, 21a, 21b) will be described in detail with reference to FIG. FIG. 6A shows a collet holder (11, 13, 15, 17, 21a, 21b) in a locked state before the nozzle collet 23 is removed, and is pressed downward by the spring 15 as in FIG. 1 (c). The ball holding portion 17 transmits the pressing force to the first pressing ball 21a via the pressing inner peripheral surface 19, and the first pressing ball 21a is fitted into the holding groove 41 so that the nozzle collet 23 is fixed. is there. Although not shown, with respect to the second pressing ball 21b which has a mirror image relationship with the first pressing ball 21a, the ball holding portion 17 presses the second pressing ball 21 through the pressing inner peripheral surface 19 in a mirror image relationship. The nozzle collet 23 is fixed by fitting the second pressing ball 21 into the holding groove 41. When the nozzle collet 23 is moved downward by applying a force larger than the pressing force of the spring 15 from the state of FIG. 6 (a), among the V-shaped surfaces constituting the holding groove 41 in FIG. 6 (a). On the upper surface, a component force is generated that pushes back the first pressing ball 21a and the second pressing ball 21 in a centrifugal direction from the center of the first tubular shape in a mirror image relationship.

Next, the first pressing ball 21a and the second pressing ball 21 to which the component force pushing back in the centrifugal direction is applied slide the ball holding portion 17 upward and push back the spring 15 in contact with the spring 15 upward in a mirror image relationship. As a result, the nozzle collet 23 can move downward with respect to the collet holders (11, 13, 15, 17, 21a, 21b), and the upper part of the second outer peripheral surface is symmetrical with the first pressing ball 21a and the second pressing ball 21. With the component force pushing back to, the transition state shown in FIG. 6B is reached, and the locked state is released. When the unlocked state is released from the locked state, the nozzle collet 23 can be easily moved downward from the state shown in FIG. 6B, so that the nozzle collet 23 can be moved to the collet holders (11, 13, 15, 17, 17, It is completely removed from the collet shaft 11 of 21a and 21b), and finally the state shown in FIG. 6C is obtained. The first pressing ball 21a and the second pressing ball 21 are released from the component force from the second outer peripheral surface of the nozzle collet 23, but are pressed by the spring 15 via the pressing inner peripheral surface 19 to receive the first cylinder. Move in the centripetal direction toward the center of the shape. When moving in the centripetal direction, the first pressing ball 21a does not fall into the collet insertion hole 35, but is located inside the first guide hole 43a or at the outer edge of the first guide hole 43a on the inner peripheral surface of the collet shaft 11. 1 The size and shape of the first guide hole 43a must be set so that the movement of the pressing ball 21a is stopped. Although not shown, the second pressing ball 21b, which has a mirror image relationship with the first pressing ball 21a, does not fall into the collet insertion hole 35, and the inside of the second guide hole or the collet shaft The size of the second guide hole and the like must be set so that the movement of the second pressing ball 21b stops at the outer edge of the second guide hole on the inner peripheral surface of 11.

Although the removal of the nozzle collet 23 from the collet holders (11, 13, 15, 17, 21a, 21b) has been described with reference to FIG. 6, the ball holding portion 17 is slid upward with a force larger than the pressing force of the spring 15. As a result, the unlocked state is set, and it can be seen that the operation of moving the nozzle collet 23 downward of the collet holders (11, 13, 15, 17, 21a, 21b) can be completed with one touch. Insertion of the nozzle collet 23 into the collet holders (11, 13, 15, 17, 21a, 21b) can be performed with one touch by the reverse mechanism of removal.

In FIG. 1, as pressing balls for fixing the nozzle collet 23, two pressing balls, a first pressing ball 21a and a second pressing ball 21b, are opposed to a mirror image relationship. As shown in the cross-sectional view of FIG. 7A, the first pressing sphere 21a and the second pressing sphere 21b have a mirror image relationship with respect to a mirror image plane passing through the first tubular central axis, and have a central axis perpendicular to the mirror image plane. The arrangement is such that they face each other on the center line through which they pass. FIG. 7B shows the arrangement of the four pressing balls of the first pressing ball 21a, the second pressing ball 21b, the third pressing ball 21c, and the fourth pressing ball 21d, but the vacuum suction arm according to the embodiment. If the number of pressing spheres is an even number, it is possible to realize an arrangement that is perpendicular to the mirror image plane and faces each other on the center line passing through the central axis in a mirror image relationship with respect to the mirror image plane passing through the central axis of the first cylinder. In the arrangement shown in FIG. 7B, the first pressing ball 21a and the third pressing ball 21c are arranged on the first center line perpendicular to the first mirror image plane passing through the tubular axis of the collet shaft 11, and the second pressing ball 21b. And the fourth pressing ball 21d are lined up on the second center line perpendicular to the second mirror image plane passing through the cylinder axis of the collet shaft 11. The names of the first pressing ball 21a, the second pressing ball 21b, the third pressing ball 21c, and the fourth pressing ball 21d are for convenience, and the third pressing ball 21c in FIG. 7B is referred to as a "second pressing ball". , The second pressing ball 21b may be called a "fourth pressing ball". In any case, the number of pressing balls may be an even number, and since FIGS. 7A and 7B are examples, six or more pressing balls may be provided. By adopting a symmetrically arranged structure based on the mirror image relationship as shown in FIGS. 7A and 7B, the forces from the even number of symmetrically arranged pressing balls are evenly applied to the nozzle collet 23. Since it is applied, even when the nozzle collet 23 moves up and down at high speed, the occurrence of vertical shake can be suppressed, the position of the fixed nozzle collet 23 can be stabilized, and the nozzle collet 23 with high accuracy and high speed can be stabilized. Automatic replacement is possible.

FIG. 10 shows an enlarged cross-sectional view of the vacuum suction arm according to the comparative example in comparison with FIG. 7, but when the number of pressing spheres is odd, the mirror image relationship with respect to the mirror image plane passing through the central axis of the first cylinder Can not do it. In particular, as shown in FIG. 10B, when the pressing ball is one of the first pressing balls 21a, the pressing force of the spring 15 is transmitted to the holding groove 41 of the nozzle collet 23 by the first pressing ball 21a, but the force Is applied only from one direction, so that the position of the fixed nozzle collet 23 is not stable and vertical shake or the like occurs, which affects the attachment / detachment of the object to be operated. Further, since the arrangement is asymmetrical, there is a high possibility that the wear of the members is biased, and it cannot be adapted to the high-speed vertical movement used in the high-precision high-speed automatic replacement system. As shown in FIG. 10A, as the first pressing ball 21a, the second pressing ball 21b, and the third pressing ball 21c, even when there are three pressing balls, a delta functional impact force is applied with the high-speed vertical movement. When applied, the force is not pushed back by the counter-pressing spheres that are in a mirror image relationship, so the position of the fixed nozzle collet 23 is not stable and affects the attachment and detachment of the object to be operated, and the members are worn. There is a high possibility that bias will occur. As shown in FIGS. 7A and 7B, a delta-functional impact force is applied along with a high-speed vertical movement by arranging counter-pressing spheres by setting an even number of pressing spheres. However, the position of the fixed nozzle collet 23 can be stabilized. Therefore, by realizing the mirror image relationship with an even number of pressing balls, it is possible to reduce the possibility that the suction / detachment of the object to be operated is adversely affected or the wear of the member is biased, and the nozzle collet 23 has high accuracy. It can be used for high speed automatic exchange system.

The material of the member constituting the vacuum suction arm according to the embodiment is mainly assumed to be metal. For example, a spline shaft can be used for the nozzle collet 23. However, the members constituting the vacuum suction arm may be made of other materials as long as they have strength and workability that can be used as a part of the precision processing apparatus. For example, a fiber-reinforced plastic (FRP) to which glass fiber or carbon fiber is added, or a composite material having a metal material inside and injection-molding plastic around it may be used.

According to the collet holders (11, 13, 15, 17, 21a, 21b) of the vacuum suction arm according to the embodiment shown in FIG. 1, the nozzle collet 23 is fixed by the component force of the downward symmetrical pressing by the spring 15. Since it is used as a force in a symmetrical direction that is a pressing force for pressing, the fixing force in the locked state is not attenuated as compared with the case where an elastic body such as rubber is used for pressing. Further, even in the high-speed vertical movement during the suction / detachment operation of the object to be operated, the nozzle collet 23 is constantly subjected to the component force of the downward mirror image of the nozzle collet 23, so that the nozzle collet 23 is shaken vertically, horizontally, and rotated. Directional blurring is unlikely to occur, and the accuracy of attachment / detachment of the object to be operated by the nozzle tip inserted into the nozzle collet 23 can be kept high.

Furthermore, by adopting a mechanism that allows the nozzle tip 51 to be freely separated from the nozzle head unit (23, 25, 51), the main replacement member can be only the nozzle tip 51, making it a cheaper precision processing device. can do. In addition, the specifications of the nozzle tip 51 can be easily changed. In particular, since the detent pin 25 is fitted to the detent groove 45 of the vacuum suction arm in the nozzle collet 23, it is easy to accurately determine the position and orientation of the fine rectangular shape at the tip of the nozzle tip 51. Therefore, it can be easily applied to a vacuum suction type precision machining apparatus equipped with a high-precision high-speed automatic exchange system.

When the nozzle collet 23 is inserted into the collet insertion hole 35 from the state of FIG. 4, the state of FIG. 2 is obtained. If there is a horizontal misalignment with each other during insertion, and the width of the misalignment is within the width of the conical surface 27 at the tip of the nozzle collet 23, the conical surface 27 contacts the lower end of the collet shaft 11. After that, the collet shaft 11 or the nozzle collet 23 moves horizontally while the lower end of the collet shaft 11 slides on the conical surface 27, and the nozzle collet 23 can be accommodated in the collet insertion hole 35 at an appropriate horizontal position.

As shown in FIG. 4, according to the nozzle collet 23 according to the embodiment of the present invention, only by changing the tip shape of the nozzle collet 23 to a shape having a conical surface 27, the nozzle collet 23 can be inserted into the collet insertion hole 35 on the vacuum suction arm side. The misalignment can be eliminated at the time of insertion. It is possible to eliminate the misalignment by a cheaper and simpler method without the need for visual adjustment of the misalignment and the need for preparing other devices.

Although the present invention has been described in accordance with the above embodiments, the statements and drawings that form part of this disclosure should not be understood as limiting the invention. Various alternative embodiments, examples and operational techniques will be apparent to those skilled in the art from this disclosure.

It is also possible to appropriately combine some of the individual technical ideas described in the above embodiments with each other. As described above, it goes without saying that the present invention includes various embodiments not described here. Therefore, the technical scope of the present invention is defined only by the matters specifying the invention relating to the scope of claims, which can be interpreted as appropriate from the above description.

11 ... Collet shaft 13 ... Spring pressing portion 15 ... Spring 17 ... Ball pressing portion 19 ... Pressing inner peripheral surface 21a ... First pressing ball 21b ... Second pressing ball 21c ... Third pressing ball 21d ... Fourth pressing ball 23 ... Nozzle Collet 25 ... Anti-rotation pin 27 ... Conical surface 31 ... Vacuum suction hole 33 ... Gap 35 ... Collet insertion hole 37 ... Through hole 39 ... Nozzle tip insertion hole 41 ... Holding groove 43a ... First guide hole 43b ... Second guide hole 43c ... 3rd guide hole 43d ... 4th guide hole 45 ... Anti-rotation groove 47 ... Nozzle inner space 49 ... Suction window 51 ... Nozzle tip 71 ... Vacuum piping joint (adapter)

Claims (6)

It has a first tubular shape having a vacuum suction hole continuous upward from the collet insertion hole at the lower end on the central axis side, and passes through the central axis that penetrates from the outer circumference of the first tubular shape to the vacuum suction hole. With respect to the mirror image plane, a collet shaft provided with first and second guide holes perpendicular to the mirror image plane and facing each other on a center line passing through the central axis, and a collet shaft.
A sliding inner peripheral surface in contact with the outer peripheral surface of the collet shaft, a tapered pressing inner peripheral surface extending downward from the sliding inner peripheral surface and extending in the centrifugal direction from the central axis, and protection continuous downward from the pressing inner peripheral surface. A tubular ball holding portion having an inner peripheral surface and slidable in the central axial direction,
The first and second pressing balls arranged in the first and second guide holes, respectively, and capable of being pressed symmetrically from the pressing inner peripheral surface,
A second tubular shape having a through hole that is continuous upward in the central axial direction from the nozzle tip insertion hole provided at the lower end portion and whose upper outer diameter shape matches the inner diameter shape of the collet insertion hole. None, a nozzle collet provided with a ring-shaped holding groove on the outer peripheral surface of the second cylinder, and
When the upper portion of the nozzle collet is inserted into the collet insertion hole, the first and second pressing balls fitted in the holding groove are pressed toward the holding groove in symmetrical directions. A vacuum suction arm featuring. Further provided with a detent pin fixed on the second tubular outer peripheral surface and below the holding groove.
When the upper part is inserted into the collet insertion hole, the detent pin fits into the detent groove provided in the outer edge of the lower end of the collet shaft and below the first guide hole in a notch shape. The vacuum suction arm according to claim 1, wherein the vacuum suction arm is fitted. A spring holding portion fixed to a part of the outer peripheral surface of the collet shaft, and
A spring that is in contact with the spring holding portion at the upper end, is in contact with the ball holding portion at the lower end, and can expand and contract in the central axis direction.
The vacuum suction arm according to claim 1 or 2, further comprising. It has a first tubular shape having a vacuum suction hole continuous upward from the collet insertion hole at the lower end on the central axis side, and passes through the central axis that penetrates from the outer circumference of the first tubular shape to the vacuum suction hole. With respect to the mirror image plane, a collet shaft provided with first and second guide holes perpendicular to the mirror image plane and facing each other on a center line passing through the central axis, and a collet shaft.
A sliding inner peripheral surface in contact with the outer peripheral surface of the collet shaft, a tapered pressing inner peripheral surface extending downward from the sliding inner peripheral surface and extending in the centrifugal direction from the central axis, and protection continuous downward from the pressing inner peripheral surface. A tubular ball holding portion having an inner peripheral surface and slidable in the central axial direction,
The first and second pressing balls arranged in the first and second guide holes, respectively, and capable of being pressed symmetrically from the pressing inner peripheral surface,
A second hole having a through hole that is continuous upward in the central axis direction from the nozzle tip insertion hole provided at the lower end portion, and the outer diameter shape of the upper portion is matched with the inner diameter shape of the collet insertion hole. The first nozzle collet, which has a tubular shape and is provided with a ring-shaped holding groove on the outer peripheral surface of the second tubular shape, is fitted into the holding groove when the upper portion of the nozzle collet is inserted into the collet insertion hole. A collet holder characterized in that the first and second pressing balls are pressed toward the holding groove in symmetrical directions. A second hole that has a through hole that is continuous upward in the central axis direction from the nozzle tip insertion hole provided at the lower end, and the outer diameter shape of the upper part matches the inner diameter shape of the collet insertion hole at the lower end of the collet holder. A nozzle collet having a tubular shape and provided with a ring-shaped holding groove on the outer peripheral surface of the second tubular shape.
The center of the collet holder, which has a first tubular shape having a vacuum suction hole continuous upward from the collet insertion hole on the central axis side and penetrates from the outer circumference of the first tubular shape to the vacuum suction hole. With respect to the mirror image plane passing through the axis, the collet shaft provided with the first and second guide holes perpendicular to the mirror image plane and facing each other on the center line passing through the central axis is in contact with the outer peripheral surface of the collet shaft. The center has a sliding inner peripheral surface, a tapered pressing inner peripheral surface that extends downward from the sliding inner peripheral surface and extends in the centrifugal direction from the central axis, and a protective inner peripheral surface that is continuous downward from the pressing inner peripheral surface. A tubular ball holding portion that can slide in the axial direction and a first and second guide holes that are arranged in the first and second guide holes and can be pressed symmetrically from the pressing inner peripheral surface. Equipped with a pressing ball,
When the upper portion of the nozzle collet is inserted into the collet insertion hole, the first and second pressing balls fitted in the holding groove are pressed toward the holding groove in symmetrical directions. Nozzle collet to do. The nozzle collet according to claim 5, further comprising a nozzle tip having an upper portion inserted into the nozzle tip insertion hole.

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