JP6949893B2 - Adsorption buffer - Google Patents

Description

The present invention relates to an adsorption buffer device that adsorbs an object to be transferred such as an electronic component.

Generally, an adsorption shock absorber that adsorbs an object to be transferred such as an electronic component is attached to an actuator. The adsorption buffer device has an adsorption portion that adsorbs an object to be transferred. Then, when the transfer target is sucked by the suction target, the actuator is driven to move the suction shock absorber toward the transfer target, and the suction portion is pressed against the transfer target. At this time, if the pressing force acting on the object to be transferred is too large, an excessive pressure may be applied to the object to be transferred. However, if the pressing force acting on the object to be transferred is too small, there is a possibility that the object to be transferred cannot be adsorbed by the suction portion.

Therefore, when the suction portion is pressed against the object to be transferred, the pressing reaction force acting on the suction portion is absorbed to prevent the pressing force from excessively acting on the object to be transferred, and the transfer is performed. For example, Patent Document 1 discloses a device that makes the pressing force acting on an object constant.

In the suction shock absorber of Patent Document 1, the movable shaft and the driven shaft are integrally movable in the axial direction, and the movable shaft and the driven shaft are integrally rotatable. The movable shaft has a suction portion that sucks the object to be transferred at the tip portion protruding from the housing, and also has an axial path that penetrates in the axial direction so as to communicate with the suction portion, and the driven shaft and the movable shaft are connected. As a result, the end of the shaft on the driven shaft side is closed. Then, in the adsorption buffer device, the adsorption target is pressed against the transfer target and the vacuum pressure is supplied to the axial path, so that the transfer target is adsorbed on the adsorption object.

Further, the suction shock absorber of Patent Document 1 includes two annular sealing members for sealing between the inner peripheral surface of the housing and the outer peripheral surface of the movable shaft, and the suction portion is pressed against the object to be transferred. Airtightness is maintained by each seal member so that the shaft path is in a vacuum state when a vacuum pressure is supplied to the shaft path in the state of being in a vacuum state. One of such seal members is arranged on the outer peripheral surface of the movable shaft on the driven shaft side, and is formed on the peripheral surface without a housing along the axial direction by the differential pressure between the vacuum pressure and the atmospheric pressure. It is pressed against the provided stepped surface. This seal member also functions as a cushioning member with which the end of the driven shaft on the movable shaft side comes into contact when the driven shaft moves toward the movable shaft side along the axial direction.

JP-A-2018-85457

However, in the suction shock absorber of Patent Document 1, when the shaft path is in a vacuum state in a state where the end portion of the driven shaft on the movable shaft side is in contact with the end portion of the sealing member on the driven shaft side, the driven shaft The end on the movable shaft side may be attracted to the end on the driven shaft side of the seal member. The cause of such adsorption is that a slight gap must be provided between the outer peripheral surface of the movable shaft on the driven shaft side and the inner peripheral surface of the seal member in order to make the movable shaft movable in the axial direction. This is because the vacuum pressure is supplied between the driven shaft and the seal member through the gap. Then, when the suction portion is pressed against the object to be transferred, it is necessary to move the driven shaft along the axial direction in order to buffer the pressing reaction force, but the end portion of the driven shaft on the movable shaft side is sealed. An extra force must be applied to pull it away from the end on the driven shaft side, and there is a risk that the pressing force acting on the object to be transferred will increase.

The present invention has been made to solve the above problems, and an object of the present invention is an adsorption buffer device capable of stably adsorbing a transfer object by applying an appropriate pressing force to the transfer object. Is to provide.

The suction shock absorber that solves the above problems includes a housing, a drive shaft housed in the housing and rotatably supported, and a drive shaft housed in the housing on the outer peripheral surface side or the inner peripheral surface side of the drive shaft. A driven shaft that can move in the axial direction with respect to the drive shaft, and a driven shaft that is connected to the driven shaft and can move in the axial direction integrally with the driven shaft, and that protrudes from the housing. A movable shaft having a suction part that sucks an object to be transferred at the tip on the opposite side and an axial path extending in the axial direction so as to communicate with the suction part, and the drive shaft and the driven shaft are orthogonal to the axial direction. The magnets magnetized on the surfaces facing each other in the direction of the movement come into contact with the outer peripheral surface of the movable shaft on the driven shaft side, and seal between the outer peripheral surface of the movable shaft on the driven shaft side and the housing. An annular seal member is provided, and a vacuum pressure is supplied to the shaft path of the movable shaft to attract the object to be transferred to the suction portion, so that the driven shaft and the movable shaft move in the axial direction. It is configured to allow movement and rotation about a central axis extending in the axial direction, and the opposing surfaces of the magnet are magnetized by different magnetic poles so that the magnet is non-contact and axial. It is possible to move in the axial direction while offsetting the overlap of the magnetic poles and applying an axial attraction force to return to the movable shaft, and the end portion of the driven shaft on the movable shaft side and the seal member. The driven shaft of the sealing member can be brought into contact with the end of the driven shaft, and at least one of the end of the driven shaft on the movable shaft side and the end of the sealing member on the driven shaft side. The gist is that a communication passage is provided to connect the outer circumference and the inner circumference of the side.

In the suction shock absorber, the communication passage is preferably provided at the end of the driven shaft on the movable shaft side.
In the suction buffer device, either one of the drive shaft and the driven shaft is provided with a protruding portion extending in a direction orthogonal to the axial direction, and the drive shaft and the driven shaft are provided on the other. A guide groove extending in the axial direction is provided, and the protruding portion abuts on the guide groove in a direction orthogonal to the axial direction, and the protruding portion guides in the axial direction along the guide groove. Is preferred.

In the suction shock absorber, the protruding portion is preferably a ball bearing.

According to the present invention, the object to be transferred can be stably adsorbed by applying an appropriate pressing force to the object to be transferred.

FIG. 2 is a cross-sectional view showing an adsorption buffer device according to an embodiment. (A) is a cross-sectional view showing the relationship between the drive shaft magnet and the driven shaft magnet, and (b) is a cross-sectional view showing the relationship between the rotation angle of the drive shaft and the torque applied to the driven shaft. (A) is an enlarged cross-sectional view of a part of the adsorption shock absorber, and (b) is a bottom view of the driven shaft. FIG. 2 is a cross-sectional view showing an adsorption buffer device according to an embodiment. (A) and (b) are side views which enlarged a part of the adsorption shock absorber.

Hereinafter, an embodiment in which the adsorption buffer device is embodied will be described with reference to FIGS. 1 to 3. The adsorption buffer device of this embodiment adsorbs an object to be transferred such as an electronic component.
As shown in FIG. 1, the housing 11 of the suction shock absorber 10 has a motor housing 12 and a cylindrical main body housing 13 connected to the motor housing 12. A rotor 14 of a motor having a rotating shaft 14a is built in the motor housing 12. The main body housing 13 is connected to the motor housing 12 so that the axial direction of the main body housing 13 coincides with the axial direction of the rotating shaft 14a.

The rotary shaft 14a is rotatably supported by the motor housing 12 via a bearing 12a. Both ends of the rotating shaft 14a penetrate the motor housing 12 and project to the outside of the motor housing 12. The end of the rotating shaft 14a on the main body housing 13 side penetrates the motor housing 12 and projects into the main body housing 13.

The suction shock absorber 10 includes a drive shaft 15 that is connected to the rotating shaft 14a and that rotates integrally with the rotating shaft 14a. The axial direction of the drive shaft 15 coincides with the axial direction of the rotating shaft 14a. The drive shaft 15 has a cylindrical large-diameter portion 15a located on the rotation shaft 14a side, and a cylindrical small-diameter portion 15b that is continuous with the large-diameter portion 15a and has an outer diameter smaller than that of the large-diameter portion 15a. The small diameter portion 15b extends from the large diameter portion 15a toward the side opposite to the rotating shaft 14a.

Inside the large diameter portion 15a, an end portion of the rotating shaft 14a on the main body housing 13 side is inserted. A flat surface 14b is formed on the outer peripheral surface of the portion of the rotating shaft 14a that is inserted inside the large diameter portion 15a. Further, in the radial direction of the rotating shaft 14a, a female screw hole 15h is formed in a portion of the large diameter portion 15a facing the flat surface 14b. A screw 14c is screwed into the female screw hole 15h. The tip of the screw 14c is in contact with the flat surface 14b of the rotating shaft 14a. As a result, the rotating shaft 14a and the driving shaft 15 are connected via the screw 14c.

The suction shock absorber 10 includes a bottomed cylindrical driven shaft 16 into which the drive shaft 15 is inserted. The axial direction of the driven shaft 16 coincides with the axial direction of the drive shaft 15. The driven shaft 16 is movable in the axial direction with respect to the drive shaft 15. The drive shaft 15 and the driven shaft 16 are housed in a storage chamber 13a formed on the motor housing 12 side inside the main body housing 13. There is a clearance between the outer peripheral surface of the drive shaft 15 and the inner peripheral surface of the driven shaft 16.

The suction shock absorber 10 includes a movable shaft 17 that is connected to the driven shaft 16 and can move in the axial direction integrally with the driven shaft 16. The axial direction of the movable shaft 17 coincides with the axial direction of the driven shaft 16. A screw insertion hole 16h is formed in the bottom portion 16e of the driven shaft 16. A female screw hole 17h is formed at the end of the movable shaft 17 on the driven shaft 16 side. Then, the fastening screw 18 inserted into the screw insertion hole 16h is screwed into the female screw hole 17h, so that the movable shaft 17 is connected to the bottom portion 16e of the driven shaft 16 via the fastening screw 18.

The main body housing 13 is formed with an insertion hole 13h through which the movable shaft 17 is inserted. The end of the movable shaft 17 opposite to the driven shaft 16 projects to the outside of the main body housing 13 through the insertion hole 13h. The movable shaft 17 can appear and disappear from the insertion hole 13h. The movable shaft 17 is a hollow columnar having a suction port 17a and an in-axis passage 17b that communicates the suction port 17a with the inside of the insertion hole 13h. The suction port 17a is open to the end surface 17e of the protruding end portion, which is the tip end portion of the movable shaft 17 opposite to the driven shaft 16.

The in-axis passage 17b has an axial path 171b extending in the axial direction of the movable shaft 17 and a radial path 172b extending in the radial direction of the movable shaft 17. The opening on the axial path 171b on the opposite side of the driven shaft 16 corresponds to the suction port 17a described above. Further, the driven shaft 16 side of the shaft path 171b is continuous with the female screw hole 17h, and the fastening screw 18 and the driven shaft 16 block the end portion of the shaft path 171b on the driven shaft 16 side. In this way, the driven shaft 16 and the movable shaft 17 are connected by the fastening screw 18, so that the driven shaft 16 and the fastening screw 18 that are connected to the movable shaft 17 connect the driven shaft 16 to the base end of the movable shaft 17 on the driven shaft 16 side. The opening on the driven shaft 16 side in the axial path 171b of the movable shaft 17 which is a portion is closed. The path 172b communicates the driven shaft 16 side of the axis 171b with the inside of the insertion hole 13h.

A cylindrical drive shaft magnet 20 is provided on the outer peripheral surface of the small diameter portion 15b of the drive shaft 15. A cylindrical driven shaft magnet 21 is provided on the inner peripheral surface of the driven shaft 16. The driven shaft magnet 21 is arranged to face the drive shaft magnet 20 in a direction orthogonal to the axial direction. The axial length of the drive shaft magnet 20 and the axial length of the driven shaft magnet 21 are the same. There is a clearance between the outer peripheral surface of the drive shaft magnet 20 and the inner peripheral surface of the driven shaft magnet 21.

As shown in FIG. 2A, in the drive shaft magnet 20, the north pole 20a and the south pole 20b are alternately magnetized so as to be divided into a plurality (four in the present embodiment) as magnetic poles in the circumferential direction. It is composed of. The driven shaft magnet 21 is divided into a plurality of magnets (four in the present embodiment) in the circumferential direction, and the north pole 21a and the south pole 21b are alternately magnetized. The outer peripheral surface of each N pole 20a of the drive shaft magnet 20 faces the inner peripheral surface of each S pole 21b of the driven shaft magnet 21. The outer peripheral surface of each S pole 20b of the drive shaft magnet 20 faces the inner peripheral surface of each N pole 21a of the driven shaft magnet 21. In this way, the outer peripheral surface of the drive shaft magnet 20 and the inner peripheral surface of the driven shaft magnet 21 are magnetized by different magnetic poles so that the outer peripheral surface of the drive shaft magnet 20 and the driven shaft magnet 21 are magnetized. The drive shaft 15 and the driven shaft 16 can rotate integrally in a non-contact state in which different magnetic poles face each other on the surfaces facing each other with the inner peripheral surface due to magnetic force and are attracted to each other. A clearance is provided between the outer peripheral surface of the drive shaft magnet 20 and the inner peripheral surface of the driven shaft magnet 21, and even if there is an eccentricity between the drive shaft 15 and the driven shaft 16, the outer peripheral surface of the drive shaft magnet 20 is provided. And the inner peripheral surface of the driven shaft magnet 21 do not come into contact with each other.

As shown in FIG. 2B, the torque applied to the driven shaft 16 increases in proportion to the rotation angle of the drive shaft 15 until the rotation angle of the drive shaft 15 reaches a predetermined angle (90 degrees in this embodiment). Become. On the other hand, when the rotation angle of the drive shaft 15 exceeds a predetermined angle (90 degrees in this embodiment), the torque applied to the driven shaft 16 is in the opposite direction, and the torque is proportional to the rotation angle of the drive shaft 15. It becomes smaller.

As shown in FIG. 3A, the insertion holes 13h are continuous with the circular accommodation hole 131h continuous with the accommodation chamber 13a and the side opposite to the accommodation chamber 13a in the accommodation hole 131h, and the hole diameter of the accommodation hole 131h. It has a small diameter hole 132h having a smaller diameter than that of the hole 132h. An annular stepped surface 135h extending in the radial direction of the movable shaft 17 is formed between the accommodating hole 131h and the small diameter hole 132h. Further, the insertion hole 13h is continuous on the side opposite to the accommodating hole 131h in the small diameter hole 132h, and is opposite to the bearing accommodating hole 133h having a larger diameter than the small diameter hole 132h and the small diameter hole 132h in the bearing accommodating hole 133h. It has a circular accommodating hole 134h having a hole diameter larger than that of the bearing accommodating hole 133h. An annular stepped surface 136h extending in the radial direction of the movable shaft 17 is formed between the accommodating hole 134h and the bearing accommodating hole 133h.

A bearing 30 is provided between the outer peripheral surface of the movable shaft 17 and the inner peripheral surface of the bearing accommodating hole 133h. The bearing 30 includes a cylindrical bearing outer cylinder 31 arranged between the outer peripheral surface of the movable shaft 17 and the inner peripheral surface of the bearing accommodating hole 133h, and the inner peripheral surface of the bearing outer cylinder 31 and the outer peripheral surface of the movable shaft 17. A plurality of balls 32 which are arranged between the bearings and come into contact with the inner peripheral surface of the bearing outer cylinder 31 and the outer peripheral surface of the movable shaft 17, and a cylindrical holding member 33 for holding the plurality of balls 32. doing. The holding member 33 is arranged between the inner peripheral surface of the bearing outer cylinder 31 and the outer peripheral surface of the movable shaft 17. The axial length of the holding member 33 is shorter than the axial length of the bearing outer cylinder 31. The holding member 33 holds a plurality of balls 32 so as to be rollable.

Since the plurality of balls 32 are in contact with the inner peripheral surface of the bearing outer cylinder 31 and the outer peripheral surface of the movable shaft 17, a preload acts on the movable shaft 17 in the radial direction of the movable shaft 17 inside the insertion hole 13h. It is positioned in the state of being. Further, since the plurality of balls 32 are rotatably held by the holding member 33, the movable shaft 17 can move and rotate in the axial direction of the movable shaft 17 inside the insertion hole 13h. Therefore, the bearing 30 moves the movable shaft 17 in the movable shaft 17 in the axial direction and the movable shaft 17 in a state where the movable shaft 17 is supported in the direction orthogonal to the axial direction of the movable shaft 17 with respect to the main body housing 13. Allows rotation.

The main body housing 13 communicates with the inside of the insertion hole 13h, and also has a suction port 17a, an in-shaft passage 17b, and a vacuum drawing port 13b for evacuating the air inside the insertion hole 13h. The evacuation port 13b communicates with the small diameter hole 132h and the bearing accommodating hole 133h. The evacuation port 13b communicates with the inside of the bearing outer cylinder 31 through an opening on the small diameter hole 132h side in the bearing outer cylinder 31. The inside of the bearing outer cylinder 31 is a discharge space 31k between the movable shaft 17 and the bearing outer cylinder 31 separated by a plurality of balls 32. Further, the discharge space 31k communicates with the path 172b. A vacuum generator 13d such as an ejector is connected to the vacuum drawing port 13b via a switching valve 13c. Therefore, the discharge space 31k is connected to the switching valve 13c via the evacuation port 13b. Further, the discharge space 31k is connected to the vacuum generator 13d via the vacuum drawing port 13b and the switching valve 13c. Atmospheric pressure and vacuum pressure are switchably supplied to the discharge space 31k (vacuum drawing port 13b) by switching the switching valve 13c.

A resin-made first seal member 41 is housed in the storage hole 134h. Therefore, the accommodating hole 134h is a first accommodating portion for accommodating the first seal member 41. The first seal member 41 is provided on the suction port 17a side of the vacuum drawing port 13b and the bearing 30 between the outer peripheral surface of the movable shaft 17 and the inner peripheral surface of the insertion hole 13h. The first seal member 41 has a disk shape. The movable shaft 17 is inserted inside the first seal member 41 in a state where the outer peripheral surface of the movable shaft 17 is in sliding contact with the inner peripheral surface of the first seal member 41, and is inserted into the outer peripheral surface of the movable shaft 17 and the first. The space between the seal member 41 and the inner peripheral surface is sealed. Therefore, the inner peripheral surface of the first seal member 41 is the first inner peripheral surface 41a forming a gap seal with the outer peripheral surface of the movable shaft 17.

Further, when the vacuum pressure is supplied to the vacuum drawing port 13b, the force due to the pressure difference between the vacuum pressure and the atmospheric pressure acts on the first seal member 41 in the axial direction of the first seal member 41, and the stepped surface. It abuts on 136h and seals between the stepped surface 136h and the first sealing member 41. Therefore, the end surface of the first seal member 41 that abuts on the stepped surface 136h is the first end surface 41b perpendicular to the first inner peripheral surface 41a, and the first end surface is formed by applying a pressure difference between the atmospheric pressure and the vacuum pressure. The sealing force at 41b acts. The axial thickness of the first seal member 41 is set to be thinner than the depth of the accommodating hole 134h, and no force in the thickness direction is generated in a state where no pressure difference is generated.

The outer diameter of the first sealing member 41 is smaller than the inner diameter of the accommodating hole 134h, and there is a clearance between the outer peripheral surface of the first sealing member 41 and the inner peripheral surface of the accommodating hole 134h. Therefore, since the gap is also provided in the radial direction, the first seal member 41 can be suppressed to a small sliding resistance to the movable shaft 17 without being restrained, and the movable shaft 17 and the first seal member 41 can be suppressed. The effect of axis misalignment with is eliminated. Therefore, the outer shape and the dimensions in the thickness direction of the first seal member 41 are shapes or dimensions that are not constrained by the accommodating holes 134h.

A cap 39 for preventing the first seal member 41 from coming off from the accommodating hole 134h is attached to the end surface of the main body housing 13 on the side opposite to the motor housing 12. The cap 39 has the same shape as the outer shape of the main body housing 13 and has a through hole 39h in the center. The movable shaft 17 passes through the through hole 39h of the cap 39.

A resin-made second seal member 42 is accommodated in the accommodating hole 131h. Therefore, the accommodating hole 131h is a second accommodating portion for accommodating the second sealing member 42. The second seal member 42 is provided on the accommodation chamber 13a side of the vacuum drawing port 13b between the outer peripheral surface of the movable shaft 17 and the inner peripheral surface of the insertion hole 13h. The second seal member 42 has a disk shape. The movable shaft 17 is inserted inside the second seal member 42 in a state where the outer peripheral surface of the movable shaft 17 is in sliding contact with the inner peripheral surface of the second seal member 42, and is inserted into the outer peripheral surface of the movable shaft 17 and the second. The space between the seal member 42 and the inner peripheral surface is sealed. Therefore, the inner peripheral surface of the second seal member 42 is the second inner peripheral surface 42a forming a gap seal with the outer peripheral surface of the movable shaft 17. In the present embodiment, in order to make the driven shaft 16 and the movable shaft 17 movable in the axial direction, between the outer peripheral surface of the movable shaft 17 on the driven shaft 16 side and the inner peripheral surface of the second seal member 42. There is a slight gap.

Further, when the vacuum pressure is supplied to the vacuum drawing port 13b, the force due to the pressure difference between the vacuum pressure and the atmospheric pressure acts on the second seal member 42 in the axial direction of the second seal member 42, and the stepped surface. It abuts on 135h and seals between the stepped surface 135h and the second sealing member 42. Therefore, the end surface of the second seal member 42 that abuts on the stepped surface 135h is the second end surface 42b perpendicular to the second inner peripheral surface 42a, and the second end surface is formed by applying a pressure difference between the atmospheric pressure and the vacuum pressure. The sealing force at 42b acts.

The outer diameter of the second seal member 42 is smaller than the inner diameter of the accommodating hole 131h, and there is a clearance between the outer peripheral surface of the second seal member 42 and the inner peripheral surface of the accommodating hole 131h. Therefore, since the gap is also provided in the radial direction, the second seal member 42 can suppress the sliding resistance to the movable shaft 17 to be small without being restrained, and the movable shaft 17 and the second seal member 42 can be suppressed. The effect of axis misalignment with is eliminated. Therefore, the outer shape and the dimensions in the thickness direction of the second seal member 42 are shapes or dimensions that are not constrained by the accommodating holes 131h.

As shown in FIG. 1, the end surface of the driven shaft 16 on the movable shaft 17 side can come into contact with the second seal member 42. Therefore, the end surface of the second seal member 42 opposite to the second end surface 42b is a contact surface 42c on which the end surface of the driven shaft 16 on the movable shaft 17 side can come into contact with the movable shaft 16. It also functions as a cushioning member for the end face on the 17 side. In a state where the end surface of the driven shaft 16 on the movable shaft 17 side is in contact with the contact surface 42c of the second seal member 42, the end surface of the driven shaft magnet 21 on the movable shaft 17 side is the movable shaft 17 of the drive shaft magnet 20. It is located on the side opposite to the movable shaft 17 from the end face on the side.

The state in which the end surface of the driven shaft 16 on the movable shaft 17 side is in contact with the contact surface 42c of the second seal member 42 is the state in which the movable shaft 17 most protrudes from the insertion hole 13h. Further, the state in which the end surface of the driven shaft 16 on the motor housing 12 side is in contact with the motor housing 12 is a state in which the movable shaft 17 is most immersed from the insertion hole 13h. Even when the movable shaft 17 is most immersed from the insertion hole 13h, the end portion of the movable shaft 17 opposite to the driven shaft 16 projects to the outside of the main body housing 13 through the insertion hole 13h.

In the axially movable range of the driven shaft 16, the driven shaft magnet 21 is arranged so that the magnet end portion protrudes toward the motor housing 12 from the drive shaft magnet 20, and the driven shaft magnet 21 and the drive shaft are arranged. Axial attractive force acts in the direction in which the ends of the magnet 20 coincide with each other. That is, the suction force acts in the direction in which the movable shaft 17 protrudes, and the suction force acts as a pressing force on the end surface of the second seal member 42 on the bottom portion 16e of the driven shaft 16. This pressing force, which is an attractive force, is configured by offsetting the driven shaft magnet 21 and the drive shaft magnet 20 in the axial direction so that the pushing force is constant regardless of the position in the movable range of the driven shaft 16. The drive shaft magnet 20 and the driven shaft magnet 21 are non-contact and can move in the axial direction while offsetting the overlap of the magnetic poles in the axial direction and applying an axial attractive force to return to the movable shaft 17.

An actuator (not shown) is driven, and the suction shock absorber 10 is moved toward the transfer object W mounted on the mounting surface W1 by the drive of the actuator, and the end surface 17e of the protruding end portion of the movable shaft 17 is transferred. It is pressed against the object W from the axial direction. In this case, the pressing reaction force from the object W to be transferred acts on the movable shaft 17, but the movable shaft 17 does not move until the pressing force due to the suction force is exceeded. Further, as the pressing operation is performed, the pressing reaction force matches the pressing force due to the suction force and becomes a balanced state, and the movable shaft 17 moves to the motor housing in a state where a constant pressing force is applied to the object W to be transferred. It becomes possible to move to the 12 side. Since the pressing force is a constant suction force, it acts as a buffer function in which a constant pressing force acts even if there is a dimensional change in the height direction of the object W to be transferred. Further, when the transfer target object W is placed on the mounting surface W1 at the transfer destination, for example, when work such as press fitting is required, it also acts as a buffer function in which a constant pressing force acts.

Further, the switching valve 13c is driven, the vacuum drawing port 13b is connected to the vacuum generator 13d, the air between the suction port 17a and the object W to be transferred is sucked from the suction port 17a, and is sucked from the suction port 17a. The generated air flows through the in-shaft passage 17b and the discharge space 31k and is sucked out from the evacuation port 13b. As a result, a vacuum state is created between the end face 17e of the protruding end of the movable shaft 17 pressed against the transfer target W and the transfer target W, and the transfer target W becomes the end face 17e of the protruding end of the movable shaft 17. Be adsorbed. Therefore, the suction port 17a sucks air in order to attract the transfer target object W to the end surface 17e of the protruding end portion of the movable shaft 17. Then, the end surface 17e of the protruding end portion of the movable shaft 17 functions as a suction portion for sucking the transfer target object W.

Subsequently, the actuator is driven in the Z-axis direction in a state where the transfer object W is attracted to the end surface 17e of the protruding end portion of the movable shaft 17, and the suction shock absorber 10 is brought into the mounting surface W1 by the drive of the actuator. Moves to the other side. Then, the moving object is transferred until the end surface of the driven shaft 16 on the movable shaft 17 side comes into contact with the contact surface 42c of the second seal member 42 by the attractive force acting between the drive shaft magnet 20 and the driven shaft magnet 21. The movable shaft 17 and the driven shaft 16 move integrally while the W is pressed against the mounting surface W1 by a constant force due to the suction force. Then, the end surface of the driven shaft 16 is in contact with the contact surface 42c of the second seal member 42, and the transfer object W is attracted to the end surface 17e of the protruding end portion of the movable shaft 17 and is attracted to the mounting surface W1. Stay away from. After that, the transfer object W is transferred to the target transfer position.

At this time, the direction of the rotation direction with the central axis of the movable shaft 17 of the transfer target object W as the center of rotation is adjusted. Specifically, in the suction buffer device 10, the rotor 14 is driven to rotate the rotating shaft 14a, and the drive shaft 15 rotates integrally with the rotating shaft 14a as the rotating shaft 14a rotates. Here, since the outer peripheral surfaces of the drive shaft magnet 20 and the inner peripheral surfaces of the driven shaft magnet 21 are magnetized by different magnetic poles, the outer peripheral surface of the drive shaft magnet 20 and the inner peripheral surface of the driven shaft magnet 21 are magnetized. The drive shaft 15 and the driven shaft 16 rotate integrally with different magnetic poles facing each other on the surfaces facing each other with the peripheral surface. As a result, the movable shaft 17 also rotates integrally with the driven shaft 16, and the direction of the moving object W in the rotation direction with the central axis of the movable shaft 17 as the center of rotation is adjusted.

By the way, as shown in FIG. 3B, on the end surface of the driven shaft 16 on the movable shaft 17 side, the cylindrical movable shaft accommodating portion 16a coaxial with the screw insertion hole 16h and having an inner diameter larger than that of the screw insertion hole 16h. Is provided, and the base end portion of the movable shaft 17 on the driven shaft 16 side is accommodated inside the movable shaft accommodating portion 16a. The movable shaft accommodating portion 16a functions as a connecting portion to be connected to the movable shaft 17.

The inside of the movable shaft accommodating portion 16a communicates with the shaft path 171b via the female screw hole 17h of the movable shaft 17. The fastening screw 18 is screwed into the female screw hole 17h while being inserted into the screw insertion hole 16h and the movable shaft accommodating portion 16a, and the end portion of the shaft path 171b on the driven shaft 16 side is closed. In particular, in the present embodiment, in order to prevent the fastening screw 18 from loosening, the fastening screw 18 is screwed into the female screw hole 17h with the screw insertion hole 16h and the female screw hole 17h filled with an adhesive. There is. Therefore, even if the driven shaft 16 and the movable shaft 17 are separate bodies, there is no gap between the driven shaft 16 and the movable shaft 17 including the female screw hole 17h and the movable shaft accommodating portion 16a.

A C-shaped contact surface 16b is provided on the end surface of the movable shaft accommodating portion 16a on the movable shaft 17 side, and the contact surface 16b is on the side opposite to the second end surface 42b of the second seal member 42. It can come into contact with the end face. The contact surface 16b corresponds to the contact portion.

The driven shaft 16 is provided with a communication passage 16c that extends in the radial direction of the contact surface 16b and communicates between the inner circumference and the outer circumference of the movable shaft accommodating portion 16a. The outer peripheral side of the movable shaft accommodating portion 16a has an atmospheric pressure, and the communication passage 16c is provided so that the inner peripheral side of the movable shaft accommodating portion 16a also has an atmospheric pressure. In the present embodiment, the depth of the movable shaft accommodating portion 16a is 0.5 mm and the width of the communication passage 16c is about 2 mm, but the atmospheric pressure is smoothly supplied to the inner peripheral side of the movable shaft accommodating portion 16a. If there is, this is not the case.

Next, the operation of this embodiment will be described.
When the vacuum generator 13d is driven, the air in the discharge space 31k is sucked out from the vacuum drawing port 13b, and when the end face 17e of the movable shaft 17 is pressed against the transfer object W, the movable shaft pressed against the transfer object W. A vacuum is created between the end surface 17e of the protruding end of the 17 and the object W to be transferred, and the object W to be transferred is attracted to the end surface 17e of the protruding end of the movable shaft 17. There is a risk that air pressure will circulate between the driven shaft 16 and the second seal member 42 through a slight gap between the outer peripheral surface of the movable shaft 17 on the driven shaft 16 side and the inner peripheral surface of the second seal member 42. However, since the communication passage 16c is formed at the end of the driven shaft 16 on the movable shaft 17 side, atmospheric pressure is supplied between the driven shaft 16 and the second seal member 42. In this way, even if the end surface 17e of the movable shaft 17 is pressed against the object W to be transferred in a state where the vacuum pressure is supplied to the vacuum drawing port 13b, the bottom portion 16e of the driven shaft 16 is the second seal member 42. Adsorption to the contact surface 42c can be suppressed, and the bottom portion 16e of the driven shaft 16 is separated from the contact surface 42c of the second seal member 42.

In the above embodiment, the following effects can be obtained.
(1) The movable shaft 17 of the driven shaft 16 is provided with a communication passage 16c that communicates the outer circumference and the inner circumference of the second seal member 42 on the driven shaft 16 side at the end of the driven shaft 16 on the movable shaft 17 side. Atmospheric pressure can be supplied between the end on the side and the end on the driven shaft 16 side of the second seal member 42. Therefore, even when the shaft path 171b is in a vacuum state while the end of the driven shaft 16 on the movable shaft 17 side is in contact with the end of the second seal member 42 on the driven shaft 16 side, the driven shaft 16 is driven. It is possible to prevent the end of the second seal member 42 on the driven shaft 16 side from being attracted to the end of the shaft 16 on the movable shaft 17 side. Therefore, it is not necessary to consider the force for pulling the end of the driven shaft 16 on the movable shaft 17 side from the end of the second seal member 42 on the driven shaft 16 side, and an appropriate pressing force is applied to the object W to be transferred. By doing so, the object W to be transferred can be stably adsorbed. Further, the axial path 171b that communicates with the suction port 17a and penetrates in the axial direction is easily formed as a passage that communicates with the suction port 17a.

(2) The second seal member 42 is supported by the stepped surface 135h, and is pressed against the stepped surface 135h provided on the movable shaft 17 side by the differential pressure between the vacuum pressure and the atmospheric pressure. Therefore, the second seal member 42 is provided so as to be movable toward the driven shaft 16 along the axial direction of the movable shaft 17, and is highly useful for providing the communication passage 16c.

(3) The second sealing member 42 is made of resin, and the higher the machined surface accuracy of the second sealing member 42, the easier it is for the sealing force on the second end surface 42b of the second sealing member 42 to act, while the driven shaft 16 The end of the second seal member 42 on the driven shaft 16 side is easily attracted to the end of the movable shaft 17 side. Therefore, the higher the machined surface accuracy of the second seal member 42, the higher the usefulness for providing the communication passage 16c.

(4) A communication passage 16c is provided in the driven shaft 16 in order to suppress suction between the driven shaft 16 and the second seal member 42. Therefore, even if the second seal member 42 is assembled by inverting the front and back sides as in the case where the communication passage is formed in the second seal member 42, the second seal member 42 and the stepped surface 135h are caused by the communication passage. It is possible to prevent an event such as the seal between the device and the device not functioning.

Next, a second embodiment that embodies the present invention will be described. In the second embodiment, for example, the driven shaft 16 is configured to smoothly rotate as the drive shaft 15 rotates. In the following description, the same components and the same control contents as those in the above-described embodiment will be designated by the same reference numerals, and the duplicated description will be omitted or simplified.

As shown in FIGS. 4 and 5, in the suction shock absorber 100, the drive shaft 15 has a ball bearing 15c as a protrusion, and the ball bearing 15c has a diameter from the outer peripheral surface of the large diameter portion 15a of the drive shaft 15. It is supported by a shaft that projects in the direction. In this embodiment, a cam follower is used as the ball bearing 15c. Further, the base end portion of the shaft is in contact with the rotating shaft 14a, and the rotating shaft 14a and the drive shaft 15 are connected to each other.

The driven shaft 16 has a guide groove 16d provided so as to extend in the axial direction of the driven shaft 16. The dimension of the guide groove 16d in the axial direction of the driven shaft 16 is longer than the stroke of the movable shaft 17 and the driven shaft 16, but may be the same. The inner surface of the guide groove 16d of the driven shaft 16 faces the outer peripheral surface of the ball bearing 15c, and the ball bearing 15c is provided so as to penetrate the guide groove 16d. When the outer peripheral surface of the ball bearing 15c comes into contact with the inner surface of the guide groove 16d, the driven shaft 16 is interlocked with the rotation of the drive shaft 15. The driven shaft 16 can move in the axial direction with respect to the drive shaft 15 along the direction in which the guide groove 16d extends.

As shown in FIG. 5A, the outer peripheral surface of the ball bearing 15c is in contact with the inner surface of the guide groove 16d. Therefore, the drive shaft 15 and the driven shaft 16 rotate integrally about the central axis extending in the axial direction.

Further, as shown in FIG. 5B, when the end surface 17e of the protruding end portion of the movable shaft 17 is pressed against the object W to be transferred from the axial direction and the movable shaft 17 moves toward the motor housing 12, the ball bearing 15c is moved. The driven shaft 16 and the movable shaft 17 can move in the axial direction with respect to the drive shaft 15 along the guide groove 16d.

Next, the operation of this embodiment will be described.
Before pressing the suction port 17a of the movable shaft 17 against the object W to be transferred, in a state where no vacuum pressure is supplied to the shaft path 171b, the central axis 14a extends in the axial direction according to a predetermined rotation pattern. The drive shaft 15 rotates about the central axis extending in the axial direction integrally with the rotation shaft 14a. In the present embodiment, the predetermined rotation pattern is a pattern that rotates a plurality of times within a range of a predetermined angle (for example, plus or minus 30 degrees) smaller than a predetermined angle (90 degrees in the present embodiment). However, it is not limited to this.

By rotating the drive shaft 15 around the central axis extending in the axial direction, a part of the outer peripheral surface of the ball bearing 15c comes into contact with the inner surface of the guide groove 16d of the driven shaft 16 with respect to the circumferential direction of the drive shaft 15. , The driven shaft 16 and the movable shaft 17 integrally with the drive shaft 15 rotate around a central axis extending in the axial direction. In this way, even when the end of the second seal member 42 on the driven shaft 16 side is attracted to the end of the driven shaft 16 on the movable shaft 17 side, the central axis 16 extends in the axial direction. The second seal member 42 can be separated from the driven shaft 16 by rotating around. Therefore, it is possible to prevent the end of the second seal member 42 on the driven shaft 16 side from being attracted to the end of the driven shaft 16 on the movable shaft 17 side.

Then, when the end surface 17e of the movable shaft 17 is pressed against the object W to be transferred, a force is applied to the movable shaft 17 and the driven shaft 16 on the drive shaft 15 side in the axial direction, and the ball bearing 15c of the drive shaft 15 becomes the driven shaft 16. The movable shaft 17 and the driven shaft 16 move toward the drive shaft 15 in the axial direction with respect to the drive shaft 15 along the guide groove 16d.

In the above embodiment, the following effects can be obtained.
(5) The drive shaft 15 is provided with ball bearings 15c extending in a direction orthogonal to the axial direction of the drive shaft 15, and the driven shaft 16 on the outer peripheral side of the drive shaft 15 is provided with a guide extending in the axial direction of the driven shaft 16. A groove 16d is provided, the ball bearing 15c abuts on the guide groove 16d, and the ball bearing 15c is axially guided along the guide groove 16d. Therefore, the ball bearing 15c and the guide groove 16d can directly transmit the rotation of the drive shaft 15 to the rotation of the driven shaft, so that the driven shaft 16 can be smoothly rotated.

(6) In addition to this, even when the drive shaft 15 rotates at a small angle, a large torque is transmitted to the driven shaft 16 as compared with the torque proportional to the angle shown in FIG. 2 (b). It is possible to prevent the end of the second seal member 42 on the driven shaft 16 side from being attracted to the end of the driven shaft 16 on the movable shaft 17 side due to the rotation of the drive shaft 15. Therefore, it is not necessary to consider the force for pulling the end of the driven shaft 16 on the movable shaft 17 side from the end of the second seal member 42 on the driven shaft 16 side, and an appropriate pressing force is applied to the object W to be transferred. By doing so, the object W to be transferred can be stably adsorbed.

(7) Further, even when the drive shaft 15 is rotated beyond a predetermined angle, the angle between the drive shaft 15 and the driven shaft 16 changes (shifts) due to the contact between the ball bearing 15c and the guide groove 16d. ), And it is not necessary to readjust the angle between the drive shaft 15 and the driven shaft 16, and the transfer object W can be rotated accurately.

(8) Further, by using the ball bearing 15c, the driven shaft 16 can be smoothly moved in the axial direction.
The above embodiment may be changed as follows.

-In the second embodiment, for example, without dividing the drive shaft magnet and the driven shaft magnet into a plurality of magnetic poles in the circumferential direction, one of the drive shaft magnet and the driven shaft magnet is of the N pole, the drive shaft magnet, and the driven shaft magnet. The other may be the S pole. As a result, the surfaces of the drive shaft magnet and the driven shaft magnet facing each other are magnetized by different magnetic poles, so that the drive shaft magnet and the driven shaft magnet are not in contact with each other and the overlap of the magnetic poles in the axial direction is offset to try to recover. It is possible to move in the axial direction while applying the attractive force in the axial direction to the movable shaft.

-In the second embodiment, for example, a protrusion may be provided instead of the ball bearing 15c.
In the second embodiment, for example, the drive shaft 15 may be provided with a guide groove, and the driven shaft 16 may be provided with a ball bearing. That is, a ball bearing may be provided on either one of the drive shaft 15 and the driven shaft 16, and a guide groove may be provided on either one of the drive shaft 15 and the driven shaft 16.

-In the above embodiment, for example, a tubular drive shaft may be provided in which the driven shaft is inserted inside and is movable in the axial direction with respect to the driven shaft. That is, any of the drive shaft and the driven shaft may be inserted inside as long as the outer peripheral surface and the inner peripheral surface of the drive shaft and the driven shaft are provided so as to face each other. In other words, the driven shaft may be provided on the outer peripheral surface side or the inner peripheral surface side of the drive shaft.

-In the above embodiment, for example, a communication hole in which the inner peripheral side and the outer peripheral side of the movable shaft accommodating portion 16a communicate with each other may be formed as a communication passage by penetrating the movable shaft accommodating portion 16a.
-In the above embodiment, for example, the second seal member 42 may be provided with a communication passage that communicates the outer circumference and the inner circumference. In this case, the communication passage 16c may or may not be provided in the movable shaft accommodating portion 16a of the driven shaft 16. That is, in at least one of the driven shaft 16 and the second seal member 42, the end portion of the driven shaft 16 on the movable shaft 17 side and the end portion of the second seal member 42 on the driven shaft 16 side come into contact with the contact portion. A communication passage that communicates the outer circumference and the inner circumference of the second seal member 42 on the driven shaft 16 side may be provided.

In the above embodiment, for example, the movable shaft accommodating portion 16a may not be formed on the driven shaft 16, and in this case, a communication passage may be provided on the end surface of the driven shaft 16, and the second seal member 42 may be provided with a communication passage. A communication passage may be provided.

In the above embodiment, for example, the driven shaft 16 and the movable shaft 17 are connected to each other without using the fastening screw 18, and the end portion of the movable shaft 17 on the axial path 171b on the driven shaft 16 side is closed. May be good. To give a specific example, the driven shaft 16 may not have the screw insertion hole 16h, and the movable shaft accommodating portion 16a may have a bottomed cylindrical shape. In this case, threads are formed on the inner peripheral surface forming the movable shaft accommodating portion 16a and the outer peripheral surface of the end portion of the movable shaft 17 on the driven shaft 16 side. The shaft 16 and the movable shaft 17 may be connected to close the end portion of the movable shaft 17 on the axial path 171b on the driven shaft 16 side.

In the above embodiment, the end face of the driven shaft 16 on the movable shaft 17 side is in contact with the second seal member 42, and the end face of the driven shaft magnet 21 on the movable shaft 17 side and the movable shaft of the drive shaft magnet 20. The end face on the 17 side may be at the same position in the axial direction of the movable shaft 17.

-In the above embodiment, the first seal member 41 and the second seal member 42 may be made of rubber or metal.
-In the above embodiment, the motor does not have to be built in the housing 11, and the rotation of the motor shaft of the motor provided outside the housing 11 is transmitted to the rotating shaft 14a via the power transmission mechanism. It may be.

Next, the technical idea that can be grasped from the above embodiment and another example will be added below.
(1) The driven shaft is a cylindrical shaft into which the drive shaft is inserted and is movable in the axial direction with respect to the drive shaft, and the magnet is provided on the outer peripheral surface of the drive shaft. Having a cylindrical drive shaft magnet and a tubular driven shaft magnet provided on the inner peripheral surface of the driven shaft and arranged to face the drive shaft magnet in a direction orthogonal to the axial direction. It is a feature.

(2) The magnets are provided on the inner peripheral surface of the driven shaft and the tubular drive shaft magnet provided on the outer peripheral surface of the drive shaft, and in a direction orthogonal to the axial direction with respect to the drive shaft magnet. It has a tubular driven shaft magnet arranged to face each other, and the drive shaft magnet and the driven shaft magnet are alternately magnetized with north and south poles so as to be divided into a plurality of magnetic poles in the circumferential direction. The outer peripheral surface of the drive shaft magnet and the inner peripheral surface of the driven shaft magnet are magnetized by different magnetic poles so that the drive shaft and the driven shaft are in non-contact and in the rotational direction. Is integrally rotatable, and the drive shaft magnet and the driven shaft magnet are non-contact and offset the overlap of the magnetic poles in the axial direction, and an axial attractive force to be restored is applied to the movable shaft. However, it is characterized by being movable in the axial direction.

(3) The housing has a stepped surface that supports the seal member, and the end portion of the seal member on the movable shaft side comes into contact with the stepped surface, and the sealed member is on the driven shaft side. The end of the driven shaft can be brought into contact with the end of the driven shaft on the movable shaft side.

W ... Transfer object, 10,100 ... Adsorption shock absorber, 11 ... Housing, 13b ... Vacuum pulling port, 13c ... Switching valve, 13d ... Vacuum generator, 13h ... Insertion hole, 14a ... Rotating shaft, 15 ... Drive shaft , 15c ... ball bearing, 16 ... driven shaft, 16a ... movable shaft accommodating portion, 16b ... contact surface, 16c ... communication passage, 16d ... guide groove, 17 ... movable shaft, 17a ... suction port, 17b ... in-shaft passage, 20 ... Drive shaft magnet, 21 ... Driven shaft magnet, 30 ... Bearing, 41 ... First seal member, 41a ... First inner peripheral surface, 41b ... First end surface, 42 ... Second seal member, 42a ... Second inner circumference Surface, 42b ... Second end surface, 42c ... Contact surface, 135h ... Step surface, 171b ... Axial path.

Claims (4)

With the housing
A drive shaft housed in the housing and rotatably supported,
A driven shaft housed in the housing and movable in the axial direction with respect to the drive shaft on the outer peripheral surface side or the inner peripheral surface side of the drive shaft.
A suction portion that is connected to the driven shaft, is movable in the axial direction integrally with the driven shaft, and attracts a transfer object at a tip portion on the opposite side of the driven shaft that protrudes from the housing, and the suction portion. A movable shaft having an axial path extending in the axial direction so as to communicate with the suction portion,
A magnet magnetized on a surface of the driving shaft and the driven shaft facing each other in a direction orthogonal to the axial direction.
An annular sealing member that comes into contact with the outer peripheral surface of the movable shaft on the driven shaft side and seals between the outer peripheral surface of the movable shaft on the driven shaft side and the housing is provided.
By supplying vacuum pressure to the shaft path of the movable shaft, the object to be transferred is attracted to the suction portion.
The driven shaft and the movable shaft are configured to allow movement in the axial direction and rotation about a central axis extending in the axial direction.
When the surfaces of the magnets facing each other are magnetized by different magnetic poles, the magnets are non-contact and offset the overlap of the magnetic poles in the axial direction, and an axial attractive force to be restored is applied to the movable shaft. However, it is movable in the axial direction,
The end of the driven shaft on the movable shaft side and the end of the sealing member on the driven shaft side can come into contact with each other.
At least one of the end of the driven shaft on the movable shaft side and the end of the seal member on the driven shaft side is provided with a communication passage that communicates the outer circumference and the inner circumference of the seal member on the driven shaft side. A suction buffer device characterized by the fact that. The suction buffer device according to claim 1, wherein the communication passage is provided at an end portion of the driven shaft on the movable shaft side. One of the drive shaft and the driven shaft is provided with a protrusion extending in a direction orthogonal to the axial direction.
A guide groove extending in the axial direction is provided on either the drive shaft or the driven shaft.
The adsorption buffer according to claim 1 or 2, wherein the protruding portion abuts on the guide groove in a direction orthogonal to the axial direction, and the protruding portion is guided in the axial direction along the guide groove. Device. The suction shock absorber according to claim 3, wherein the protruding portion is a ball bearing.

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