JP5792988B2 - SCARA robot - Google Patents

Description

  The present invention provides a scalar in which a bellows-like member for clean room or dustproof and splashproof is provided on the top and bottom of an operating shaft that moves up and down at the tip of an arm that is rotatably provided in the horizontal direction. Type robot.

  Conventionally, SCARA robots have been used to mount electronic components. In such SCARA robots, external dust and water droplets can be prevented from entering the inside, and conversely, internal dust and In order to prevent oil droplets or the like from scattering to the outside, there is one in which a bellows-like cover member is provided between the upper and lower portions of the operating shaft and the cover of the robot body (see, for example, Patent Document 1). ). The SCARA robot includes a main body arm, a first arm that can rotate horizontally with respect to the main body arm, and a second arm that can rotate horizontally with respect to the first arm. A ball screw spline that can be rotated is installed. The ball screw spline has anti-static bellows at the top and bottom, respectively, and this anti-static bellows ensures the cleanliness of the SCARA robot or the clean room where the SCARA robot is installed. Is done.

JP-A-11-138488

  In such a SCARA type robot, a motor is used to move the ball screw spline up and down and rotate, and this motor generates heat upon operation. And when this heat generation becomes excessive, there arises a problem that the operating efficiency of the motor is deteriorated or the motor is easily damaged. In the above-described conventional SCARA robot, bellows are provided above and below the ball screw spline, respectively, and when the ball screw spline moves up and down, air is moved between the upper side and the lower side across the second arm. Move. However, in the above-described SCARA robot, the ball screw spline is moved by the operation of the motor via the timing belt, so that the motor is installed at a position away from the upper and lower bellows. For this reason, a motor cannot be efficiently cooled with the air which moves between upper and lower bellows.

  The present invention has been made to cope with such problems, and an object of the present invention is to provide a SCARA robot that has excellent dustproof and drip-proof properties and can prevent overheating of a motor. In the description of each constituent element of the present invention below, the reference numerals of corresponding portions of the embodiment are shown in parentheses in order to facilitate understanding of the present invention. The present invention should not be construed as being limited to the configurations of the corresponding portions indicated by the reference numerals of the forms.

In order to achieve the above-mentioned object, a structural feature of the SCARA robot according to the present invention is a SCARA robot (A, C) that moves the operating shaft (32) in the horizontal direction, and the side of the operating shaft. A cover member (31, 58) that covers the rotating shaft, a rotation motor (34) that rotates the operating shaft, an upper bellows-like member (50) that is disposed above the cover member and moves up and down in conjunction with the operating shaft, and a cover member And a lower bellows-like member (60) that moves up and down in conjunction with the operating shaft. The cover member and the upper bellows-like member, and the cover member and the lower bellows-like member communicate with each other for rotation. motor is disposed between the upper bellows-like member and the lower bellows-like member, the operating shaft is detachably communicates with the spline shaft (32a) driven by a rotating motor, the upper end of the spline shaft The extension shaft (32b, 32c) protrudes to the outside of the cover member, and the extension shaft passes through the upper insertion hole (31a) formed on the upper surface of the cover member and extends upward from the cover member. and extending the relay shaft (32 b), is detachably connected to an upper end of the relay shaft, in Rukoto consists out with coupling shaft upper end of the upper bellows-like member is fixed through the housing (32c).

In the SCARA robot according to the present invention, the upper bellows-like member is arranged on the upper part of the cover member that covers the side of the operating shaft, the lower bellows-like member is arranged on the lower part of the cover member, and the upper bellows-like member and the lower bellows It communicates with the shaped member via a cover member. And the motor for rotation is arrange | positioned between the upper bellows-like member and the lower bellows-like member. For this reason, when the operating shaft rises, the upper bellows-like member expands and the lower bellows-like member contracts, so that the air in the lower bellows-like member moves to the upper bellows-like member side. Further, when the operating shaft descends, the upper bellows-like member contracts and the lower bellows-like member extends, so that the air in the upper bellows-like member moves toward the lower bellows-like member.

Thus, an air flow is generated between the upper bellows-like member and the lower bellows-like member, and the rotating motor is efficiently cooled because it is located in the flow. For this reason, it is prevented that the rotation motor is overheated and the operating efficiency is lowered or easily damaged. In addition, since the upper bellows-like member and the lower bellows-like member are provided above and below the operating shaft, even if the operating shaft moves up and down, there is no volume change in the entire interior of the upper bellows-like member and the lower bellows-like member. No pressure fluctuations occur. This makes it difficult for the upper bellows-like member and the lower bellows-like member to be damaged or deteriorated. Furthermore, according to the present invention, the operating shaft can be rotated while being movable up and down. Further, according to the present invention, the part that requires machining accuracy because it moves up and down on the working shaft and rotates in the direction around the shaft is constituted by a spline shaft, and the part that protrudes outside the cover member on the working shaft is formed by an extension shaft. It is composed. For this reason, it is not necessary to extend the spline shaft to protrude outside the cover member. Further, as the extension shaft, an inexpensive one with a simple configuration can be used. Moreover, since the extension shaft can be attached to and detached from the spline shaft, it can be easily replaced.

Another feature of the structure of the SCARA type robot according to the present invention, with the upper portion bellows member and the lower bellows-like member, and between the rotary motor and the operating shaft, the rotational speed of the rotating motor The reduction gear (35) which decelerates and transmits to the operating shaft is installed. According to the present invention, in addition to the rotation motor, the speed reducer that reduces the rotation speed of the rotation motor can be cooled by the air flow generated between the upper bellows-like member and the lower bellows-like member.

  Still another structural feature of the SCARA robot according to the present invention is that the upper bellows-like member is disposed on the outer periphery of the operating shaft, and the upper bellows-like member is placed between the upper end of the upper bellows-like member and the upper end of the operating shaft. A rotating seal mechanism (51, 52, 53, 53d) is provided that allows the operating shaft to rotate with respect to the bellows-like member and seals between the upper end of the upper bellows-like member and the upper end of the working shaft. . According to the present invention, it is possible to prevent the upper bellows-like member from rotating even when the operating shaft rotates in the direction around the axis. Therefore, it is possible to prevent the upper bellows-like member from being damaged due to repeated twisting. Further, it is possible to reliably seal between the upper end portion of the upper bellows-like member and the upper end portion of the operating shaft.

  Still another structural feature of the SCARA robot according to the present invention is that the lower bellows-like member is disposed on the outer periphery of the operating shaft, and the lower bellows-like member is disposed between the lower end portion of the lower bellows-like member and the lower end portion of the operating shaft. A rotating seal mechanism (61, 62, 63, 63e) is provided that allows the operating shaft to rotate with respect to the bellows-like member and seals between the lower end of the lower bellows-like member and the lower end of the actuating shaft. . According to the present invention, it is possible to prevent the lower bellows-like member from rotating even if the operating shaft rotates in the direction around the axis. Therefore, it is possible to prevent the lower bellows-like member from being damaged due to repeated torsion. Further, it is possible to reliably seal between the lower end portion of the lower bellows-like member and the lower end portion of the operating shaft.

  Still another structural feature of the SCARA robot according to the present invention is that the operating shaft is formed in a cylindrical shape. According to the present invention, since the operating shaft is formed in a hollow cylindrical shape, the inside of the operating shaft can be used to accommodate wiring and piping.

  Still another structural feature of the SCARA robot according to the present invention is that the operating shaft is movably supported and includes an arm (20) that forms a space with the cover member. The upper insertion hole (31a) is formed in the upper part of the space forming portion made of the above, the lower insertion hole (58c) is formed in the lower part, and the operating shaft is inserted into the upper insertion hole and the lower insertion hole. According to the present invention, the space forming portion is configured by the arm supporting the operating shaft and the cover member, and the upper insertion hole and the lower insertion hole provided in the space forming portion are inserted into the upper bellows shape in order to insert the operating shaft. The member can communicate with the lower bellows-like member.

  Still another structural feature of the SCARA robot according to the present invention is that an attachment hole (25) and a communication hole (69, 69a) penetrating vertically are formed in the arm, and the cover member is formed as an attachment hole. It is arranged above and below the arm across the communication hole so that the operating shaft is inserted into the mounting hole and air is allowed to flow between the upper part and the lower part of the cover member through the communication hole.

  In this case, the upper insertion hole is located at the upper part of the cover member, and the lower insertion hole is located at the lower part of the cover member. And an arm comes to be located between the upper part of a cover member, and a lower part, but an operating shaft can be penetrated up and down of a cover member by forming a mounting hole in an arm. Also, by arranging cover members above and below the arm, even if the arm is positioned between the upper and lower portions of the cover member, the upper and lower portions of the cover member are communicated by forming a communication hole in the arm. And let the air flow.

  Still another structural feature of the SCARA robot according to the present invention is that the cross-sectional area of the portion where the air flows in the communication hole is the portion where the air flows between the inner peripheral surface of the upper insertion hole and the outer peripheral surface of the operating shaft. And the cross-sectional area of the portion through which the air flows between the inner peripheral surface of the lower insertion hole and the outer peripheral surface of the operating shaft. In this case, the cross-sectional area of the portion where the air flows between the inner peripheral surface of the upper insertion hole and the outer peripheral surface of the operating shaft, and the portion where the air flows between the inner peripheral surface of the lower insertion hole and the outer peripheral surface of the operating shaft The cross-sectional area is the same as or the cross-sectional area of the communication hole is made larger. According to the present invention, it is possible to reduce a change in the overall internal pressure in the upper bellows-like member, the cover member, and the lower bellows-like member as the operating shaft moves up and down.

1 is a perspective view showing a SCARA robot according to a first embodiment of the present invention. It is the perspective view which showed the SCARA type robot of standard specification. It is sectional drawing which showed the SCARA type | mold robot when an operating shaft raises. It is sectional drawing which showed the SCARA type | mold robot when an operating shaft descend | falls. It is sectional drawing which showed the attachment structure of the upper bellows-shaped member. It is sectional drawing which showed the connection part of a spline shaft and a relay shaft. It is sectional drawing which showed the connection part of an upper bellows-shaped member and a connection shaft. It is sectional drawing which showed the attachment structure of the lower bellows-shaped member. It is sectional drawing which showed the connection part of a lower bellows-shaped member and a cylindrical member. It is sectional drawing which showed the connection part of a lower bellows-shaped member and a connection shaft. It is the perspective view which showed the communicating hole provided in the 2nd arm. It is the perspective view which showed the state which the operating shaft of the SCARA-type robot which concerns on 2nd Embodiment of this invention raised. It is the perspective view which showed the state which the operating shaft of the scalar type robot which concerns on 2nd Embodiment of this invention fell. It is the perspective view which showed the state which fixed wiring etc. to the housing of the upper end of an operating shaft. It is the perspective view which showed the state which pulled out wiring etc. from the lower end of the operating shaft, and was connected to each apparatus.

(First embodiment)
Hereinafter, a SCARA robot according to a first embodiment of the present invention will be described with reference to the drawings. FIG. 1 shows a SCARA robot A according to the embodiment. The SCARA robot A is provided above and below the base 10, the first arm 18, the second arm 20, the lifting / lowering driving device 30 provided on the second arm 20, and the lifting / lowering driving device 30. An upper bellows-like member 50 and a lower bellows-like member 60 are provided. For example, the SCARA robot A is provided with an upper bellows-like member 50 and a lower bellows-like member 60 in the standard SCARA robot B shown in FIG. It is added.

  The base unit 10 is fixedly installed on a floor, a stand or the like. As shown in FIGS. 3 and 4, a rectangular box-shaped case 11, a motor 12 fixedly installed on the upper part of the case 11, And a speed reducer 13 installed on the upper surface 11 a of the case 11. In the following description, the up-down direction and the left-right direction will be described based on FIGS.

  A mounting hole 11b is formed on the left side of the upper surface portion 11a of the case 11, and the motor 12 and the speed reducer 13 are mounted on the upper surface portion 11a via the mounting hole 11b. The motor 12 includes a rotating shaft 12b rotatably supported by a motor case 12a via a bearing, a rotor provided on the outer periphery of the rotating shaft 12b, a stator disposed opposite to the outer periphery of the rotor, a rotation detection resolver, and the like. It consists of The motor 12 has a rotating shaft 12b protruding upward, and passes through the mounting hole 11b upward from below, and is connected to the input portion 13a of the speed reducer 13, and the motor case 12a is connected to the motor case 12a. It is assembled to the case 11 by being fixed to the lower surface of the upper surface portion 11a.

  The speed reducer 13 is known as a harmonic drive (registered trademark), and although not described in detail, an input unit 13 a connected to the rotating shaft 12 b of the motor 12 and an output unit connected to the first arm 18. 13b. And the bearing 14 is provided in the outer periphery of the output part 13b, and the 1st arm 18 is supported by this bearing 14 so that rotation on the horizontal surface with respect to the case 11 is possible. Further, the rotational speed of the motor 12 is decelerated and transmitted to the first arm 18 via the rotating shaft 12b, the input unit 13a, and the output unit 13b.

  One end portion of the flexible tube 15 extending toward the cover 31 described later is fixed to the right side portion of the upper surface portion 11a of the case 11 by an attachment member 15a. Inside the flexible tube 15, various wirings, suction pipes and the like (hereinafter referred to as wirings 16) are accommodated. Further, at the lower part of the right side surface portion 11c of the case 11, various ends in the case 11 such as various wirings and suction pipes are connected to the wiring and piping outside the case 11 (hereinafter referred to as wiring 17). An exhaust joint 17a is provided for connection. The exhaust joint 17 a and the wiring 16 in the flexible tube 15 are connected in the case 11. In addition, a user wiring connector 17b is provided in the upper portion of the right side portion 11c above the exhaust joint 17a.

  The first arm 18 is formed in an oval plate shape. A mounting recess having a low ceiling surface is formed on the right side of the lower surface of the first arm 18, and the output portion 13b of the speed reducer 13 is fixed to the mounting recess. A mounting recess having a shallow depth is formed in the left side portion of the upper surface of the first arm 18, and a speed reducer 23 to be described later is fixedly installed in the mounting recess, and the speed reducer 23 and the motor 22 are interposed therebetween. The second arm 20 is attached.

  The second arm 20 is formed in an oval plate shape that is longer in the major axis direction than the first arm 18 and has a small thickness, and a mounting hole 21 penetrating vertically is formed on the right side portion thereof. Yes. Then, the motor 22 projects the rotating shaft 22b downward, penetrates the mounting hole 21 downward from above, fixes the motor case 22a to the upper surface of the second arm 20, and the second It is assembled to the arm 20. The motor 22 has the same vertical model as the motor 12 described above, but is of the same model. In the present embodiment, the second arm 20 constitutes an arm according to the present invention.

  The speed reducer 23 is also of the same model as that of the speed reducer 13 described above, but is composed of the same model, and has an input portion 23a and a first arm connected to the rotating shaft 22b of the motor 22. 18 is connected to the output unit 23b. The speed reducer 23 reduces the rotational speed of the rotating shaft 22 b of the motor 22 and transmits it to the first arm 18. And the bearing 24 is provided in the outer periphery of the output part 23b. The second arm 20 is rotatably supported with respect to the first arm 18 via the bearing 24. Further, the driving force of the motor 22 is transmitted to the first arm 18 through the rotating shaft 22b, the input unit 23a, and the output unit 23b. A mounting hole 25 through which an operation shaft 32 described later is inserted is formed in the left portion of the second arm 20.

  The up-and-down rotation drive device 30 is provided on the left side of the second arm 20, and includes a cover 31, a hollow operation shaft 32 that is vertically disposed through the mounting hole 25, and the operation shaft 32 in the direction around the axis. And a lifting device 40 that moves the operating shaft 32 in the vertical direction. Further, the operating shaft 32 is connected to the spline shaft 32a constituting the main body portion and the upper end of the spline shaft 32a, and relays through the cylindrical insertion hole 31a formed on the upper surface of the cover 31 and extends upward to the outside. The shaft 32b includes a connecting shaft 32c connected to the upper end of the relay shaft 32b, and a connecting shaft 32d connected to the lower end of the spline shaft 32a. The relay shaft 32b and the connecting shaft 32c constitute an extension shaft according to the present invention. Moreover, the upper insertion hole which concerns on this invention is comprised by the insertion hole part 31a.

  The cover 31 is formed in a stepped box shape with the left side portion being higher than the right side portion, and is provided over substantially the entire upper surface of the second arm 20. The cover 31 has a portion positioned above the second arm 20 of the spline shaft 32a, the rotating device 33, and the lifting device 40 in a state where the left portion is located in a high portion on the left side. And surrounding from above. In addition, the right-side portion of the upper surface of the cover 31 is formed with an upright cylindrical projecting accommodating portion 31b that projects upward.

  The rotating device 33 includes a motor 34 and a speed reducer 35 through which the spline shaft 32a passes. The motor 34 is fixedly installed on the second arm 20 through the mounting hole 25, and is provided on the outer periphery of the cylindrical rotating shaft 34b and the rotating shaft 34b that are rotatably supported in the motor case 34a. A rotor, a stator disposed opposite to the outer periphery of the rotor, a rotation detection resolver, and the like. The reducer 35 is of the same model as the reducers 13 and 23 described above, and includes an input unit 35a and an output unit 35b. And the bearing 36 is provided in the outer periphery of the output part 35b.

  A ball spline nut 37 is connected to the outer ring of the bearing 36 via an attachment member 37a. A plurality of vertical grooves are formed on the inner circumferential surface of the ball spline nut 37 at regular intervals in the circumferential direction. The spline shaft 32a is made of a steel cylindrical shaft having a plurality of vertical grooves 32e (see FIG. 11) formed on the outer peripheral surface, and the vertical grooves 32e are engaged with the vertical grooves of the ball spline nut 37, The motor 34, the speed reducer 35, and the ball spline nut 37 are installed so as to be movable up and down. The lower portion of the spline shaft 32a is rotatably supported by the second arm 20 via a ball spline nut 37, a mounting member 37a and a bearing 36, and the rotation generated by the operation of the motor 34 is decelerated by the speed reducer 35. And rotate together with the ball spline nut 37.

  As shown in FIG. 5, the upper end portion of the spline shaft 32 a is provided in the elevating device 40 so as to be rotatable around the axis by fixed bearings 38 a and 38 b and fixed in the vertical direction. The connecting member 41 is supported. The lifting device 40 includes a connecting member 41, a ball screw nut 42, a ball screw shaft 43, and a motor 44. The motor 44 is fixedly installed on the right side of the portion of the second arm 20 to which the motor 34 is attached. The ball screw shaft 43 is connected to the rotation shaft of the motor 44 and rotates around the shaft by the operation of the motor 44.

  The ball screw nut 42 is screwed to the ball screw shaft 43, and the connecting member 41 connects the ball screw nut 42 and the upper end portion of the spline shaft 32a. For this reason, when the ball screw shaft 43 rotates in the direction around the axis by the operation of the motor 44, the ball screw nut 42 moves up and down along the ball screw shaft 43, whereby the spline shaft 32a also passes through the connecting member 41. Move up and down. The upper end portion of the ball screw shaft 43 protrudes into the protruding accommodating portion 31 b of the cover 31.

  A relay shaft 32b is connected to the upper end of the spline shaft 32a via a bearing nut 45. The relay shaft 32b is composed of an aluminum cylindrical member whose outer diameter and inner diameter are set to be substantially the same as those of the spline shaft 32a, and the surface thereof is anodized. Thereby, corrosion resistance and wear resistance are improved. Further, as shown in FIG. 6, a connecting flange portion 46 protruding outward is formed at the lower end portion of the relay shaft 32b, and a ring-like shape protruding downward is formed on the outer periphery of the lower surface of the flange portion 46. The protrusion 46 a is formed along the peripheral edge of the flange portion 46. A plurality of screw insertion holes (not shown) penetrating vertically are formed between the main body portion of the relay shaft 32b in the flange portion 46 and the protrusion 46a.

  The bearing nut 45 includes a cylindrical bearing nut main body 45a and a flange portion 45b extending outward from the outer peripheral upper portion of the bearing nut main body 45a along the circumference. The bearing nut main body 45a is fixed to the spline shaft 32a by screwing screws together with the upper end outer periphery of the spline shaft 32a positioned on the inner peripheral side. The flange portion 45b is formed in a size that can be fitted inside the protrusion 46a of the flange portion 46, and a plurality of screw holes (not shown) penetrating vertically are formed at the same interval as the screw insertion holes of the flange portion 46. Has been. And the relay shaft 32b inserts the flange part 45b in the inside of the protrusion 46a, inserts the screw 47 from the upper part of the screw insertion hole of the flange part 46, and screws the screw 47 into the screw hole of the flange part 45b. Are connected to the spline shaft 32a. The upper end surface of the bearing nut 45 and the lower surface of the relay shaft 32b are sealed with an O-ring 47a.

  A cylindrical connecting shaft 32c is connected to the upper end of the relay shaft 32b, and an upper bellows-like member 50 is attached between the insertion hole 31a of the cover 31 and the upper portion of the connecting shaft 32c. As shown in FIG. 7, a connecting flange portion 48 protruding outward is formed at the upper end portion of the relay shaft 32b, and a plurality of screw holes (see FIG. (Not shown) is formed along the circumference. The connecting shaft 32c is made of a steel tubular member having a shorter axial length than the relay shaft 32b and having the same outer diameter and inner diameter as the relay shaft 32b. Is given.

  A connecting flange portion 49 protruding outward is formed at the lower end of the connecting shaft 32 c, and a ring-shaped protrusion 49 a protruding downward is formed on the outer periphery of the lower surface of the flange portion 49. It is formed along the peripheral edge. A plurality of screw insertion holes penetrating vertically are formed at the same interval as the screw holes of the flange portion 48 between the main body portion of the connecting shaft 32 c in the flange portion 49 and the protrusion 49 a. The connecting shaft 32c is formed by inserting a flange portion 48 into the protrusion 49a, inserting a screw 48a from above the screw insertion hole of the flange portion 49, and screwing the screw 48a into the screw hole of the flange portion 48. It is connected to the relay shaft 32b. The upper surface of the flange portion 48 and the lower surface of the flange portion 49 are sealed with an O-ring 48b.

  A housing 52 is attached to the upper outer periphery of the connecting shaft 32c via a bearing 51, and a housing 53 is attached above the bearing 51 and the housing 52 on the upper outer periphery of the connecting shaft 32c. In the bearing 51, the inner ring 51a is fixed to the outer periphery of the connecting shaft 32c, and the outer ring 51b is fixed to the housing 52, so that the housing 52 cannot move in the vertical direction with respect to the connecting shaft 32c, and the shaft 51 can be moved in the direction around the axis. It is connected so that it can rotate. The housing 52 has a flange-like horizontal portion 52a extending from the portion spaced from the outer peripheral surface of the coupling shaft 32c to the outer peripheral side above the bearing 51, and the outer peripheral surface of the bearing 51 from the outer peripheral side of the lower surface of the horizontal portion 52a. A bearing housing portion 52b extending downward along the upper surface of the horizontal portion 52a and a fixing portion 52c extending upward from the inner peripheral side of the upper surface of the horizontal portion 52a (an end surface seal 53d, which will be described later, is contracted and fixed).

  The space between the coupling shaft 32c and the inner ring 51a of the bearing 51 and the space between the outer ring 51b of the bearing 51 and the bearing housing 52b of the housing 52 are sealed by O-rings 51c and 51d, respectively. Further, a groove is formed along the circumference in the lower part of the inner peripheral surface of the bearing storage portion 52b, and a circlip 52d is installed in this groove. The circlip 52d prevents the bearing 51 from coming out of the bearing housing portion 52b.

  The housing 53 includes a flange-shaped horizontal portion 53a extending from the upper end of the outer peripheral surface of the connecting shaft 32c to the outer peripheral side, and an outer peripheral surface of the connecting shaft 32c and a fixing portion 52c of the housing 52 from the inner peripheral side of the lower surface of the horizontal portion 53a. The sliding support portion 53b extends downward, and the seal storage portion 53c extends downward from the lower surface outer peripheral side of the horizontal portion 53a toward the upper surface outer periphery of the housing 52. The inner peripheral surface of the housing 53 is fixed to the outer peripheral surface of the connecting shaft 32c by screwing together, and a sealing agent is applied to the boundary surface between the two. An end face seal 53d is installed in a space surrounded by the lower surface of the horizontal portion 53a, the seal housing portion 53c, the outer peripheral surface of the fixed portion 52c, and the upper surface of the horizontal portion 52a.

  Therefore, the inner ring 51a and the housing 53 of the bearing 51 are fixed to the connecting shaft 32c, and the outer ring 51b and the housing 52 of the bearing 51 are rotatable with respect to the connecting shaft 32c. When the housing 52 rotates, the end surface seal 53d slides with respect to the lower surface of the horizontal portion 53a. Further, the contacting portions of the coupling shaft 32c, the bearing 51, the housing 52, and the housing 53 are sealed with O-rings 51c and 51d, a sealant, and an end face seal 53d. Note that the end face seal 53d is formed of a contact seal and prevents dust and the like from passing therethrough.

  The upper bellows-like member 50 is composed of a stretchable member formed of a urethane resin in a bellows shape, and cylindrical fixing portions 50a and 50b are formed at a lower end portion and an upper end portion, respectively. As shown in FIG. 6, the fixing portion 50 a covers the outer peripheral surface of the insertion hole portion 31 a of the cover 31, and a clamp member 55 is attached to the outer periphery via a urethane sheet 54. The clamp member 55 includes a belt-like portion 55a and a fastening portion 55b provided with a screw. The belt-like portion 55a is wound around the fixed portion 50a via the urethane sheet 54, and the belt-like portion 55a is fastened by the fastening portion 55b. Thus, the fixing portion 50a is fixed to the outer peripheral surface of the insertion hole portion 31a.

  As shown in FIG. 7, the fixing portion 50b covers the outer peripheral surface of the housing 52, and a clamp member 56 is attached to the outer periphery via a urethane sheet 54a. Similar to the clamp member 55, the clamp member 56 includes a belt-like portion 56a and a fastening portion 56b provided with a screw. The belt-like portion 56a is wound around the fixing portion 50b via the urethane sheet 54a, and the fastening portion 56b. The fixing portion 50b is fixed to the housing 52 by tightening the belt-like portion 56a. In addition, the urethane sheet 54a and the housing 52 are sealed by O-rings 57a and 57b that are spaced apart from each other in the vertical direction.

  As shown in FIG. 8, a cylindrical member 58 that covers the reduction gear 35 and the ball spline nut 37 is provided on the left side portion of the lower surface of the second arm 20. The cylindrical member 58 is configured with a large-diameter portion 58a whose upper portion covers the speed reducer 35, and an inclined portion 58b that covers the ball spline nut 37 and has a smaller diameter as it goes downward. A connecting portion 58c having a small diameter and a short axial length is formed below the inclined portion 58b. The cylindrical member 58 and the cover 31 constitute a cover member according to the present invention, and the cover member and the second arm 20 constitute a space forming portion according to the present invention. Moreover, the lower insertion hole which concerns on this invention is comprised by the connection part 58c.

  The lower part of the spline shaft 32a protrudes downward from the lower end opening of the connecting part 58c. The connecting shaft 32d is connected to the lower end of the portion protruding from the lower end opening of the connecting portion 58c of the spline shaft 32a, and the lower bellows-like member 60 is attached between the connecting portion 58c and the connecting shaft 32d. Yes.

  The connecting shaft 32d is formed in a large-diameter cylindrical shape whose upper part covers the lower end portion of the spline shaft 32a, and the lower part is formed in a small-diameter cylindrical shape having an outer diameter and an inner diameter comparable to the spline shaft 32a. It is formed in a cylindrical shape. A slit tightening portion 59 shown in FIG. 9 is formed at the upper end of the connecting shaft 32d. By tightening the slit tightening portion 59 with a bolt 59a, the connecting shaft 32d is connected to the spline shaft 32a. It is fixed. Further, as shown in FIG. 10, a housing 62 is attached to the upper outer periphery of the small-diameter cylindrical portion of the connecting shaft 32d via a bearing 61, and the bearing 61 and the housing 62 on the outer periphery of the connecting shaft 32d. A housing 63 is attached below the housing.

  In the bearing 61, the inner ring 61a is fixed to the outer periphery of the connecting shaft 32d, and the outer ring 61b is fixed to the housing 62, so that the housing 62 cannot be moved in the vertical direction with respect to the connecting shaft 32d. It is connected so that it can rotate. The housing 62 is located below the bearing 61 and extends along the outer peripheral surface of the bearing 61 from the outer peripheral side of the upper surface of the horizontal portion 62a. The bearing housing portion 62b that extends upward, the fixing portion 62c that extends downward from the lower inner peripheral edge and the lower outer peripheral edge of the horizontal portion 62a (an end surface seal 63e described later is fixed by being contracted) and a seal. It is comprised by the accommodating part 62d.

  The coupling shaft 32d and the inner ring 61a of the bearing 61 and the outer ring 61b of the bearing 61 and the bearing housing portion 62b of the housing 62 are sealed by O-rings 61c and 61d, respectively. Further, a groove is formed along the circumference in the upper part of the inner peripheral surface of the bearing storage portion 62b, and a circlip 62e is installed in this groove. The circlip 62e prevents the bearing 61 from coming out of the bearing housing portion 62b.

  The housing 63 includes a flange-like horizontal portion 63a extending from the outer peripheral surface of the connecting shaft 32d to the outer peripheral side so as to close the lower end openings of the fixing portion 62c and the seal storage portion 62d, and an upper surface inner peripheral side of the horizontal portion 63a. A bearing inner ring fixing portion 63b extending upward between the outer peripheral surface of the coupling shaft 32d and the fixing portion 62c of the housing 62, and an outer periphery of the coupling shaft 32d after extending downward from one of the lower surfaces of the bearing inner ring fixing portion 63b. A C-shaped slit fastening portion 63c extending in the circumferential direction from both sides along the surface. The housing 63 is fixed to the coupling shaft 32d by fastening the slit fastening portion 63c with a bolt 63d. Further, an end face seal 63e is installed in a space surrounded by the lower surface of the horizontal portion 62a, the fixing portion 62c, the seal housing portion 62d, and the upper surface of the horizontal portion 63a, and between the coupling shaft 32d and the bearing inner ring fixing portion 63b of the housing 63. Is sealed by an O-ring 63f.

  For this reason, the inner ring 61a of the bearing 61 and the housing 63 are fixed to the connecting shaft 32d, and the outer ring 61b of the bearing 61 and the housing 62 are rotatable with respect to the connecting shaft 32d. And when the housing 62 rotates, the end surface seal 63e slides with respect to the horizontal part 63a. Further, the contacting portions of the coupling shaft 32d, the bearing 61, the housing 62, and the housing 63 are sealed with O-rings 61c, 61d, 63f and an end face seal 63e. The end face seal 63e has the same configuration as the end face seal 53d described above.

  The lower bellows-like member 60 has the same configuration as the upper bellows-like member 50, and cylindrical fixing portions 60a and 60b are formed at the upper end and the lower end of the bellows-like portion, respectively. As shown in FIG. 9, the fixing portion 60 a covers the outer peripheral surface of the connecting portion 58 c, and a clamp member 65 is attached to the outer periphery via a urethane sheet 64. The clamp member 65 includes a band-shaped portion 65a and a fastening portion 65b provided with a screw. The band-shaped portion 65a is wound around the connecting portion 58c via the urethane sheet 64, and the belt-shaped portion 65a is tightened by the fastening portion 65b. Thus, the fixing part 60a is fixed to the connecting part 58c. Further, the urethane sheet 64 and the connecting portion 58c are sealed by O-rings 66a and 66b that are spaced apart from each other.

  The fixing portion 60b covers the outer peripheral surface of the bearing storage portion 62b of the housing 62, and a clamp member 67 is attached to the outer periphery via a urethane sheet 64a. Like the clamp member 65, the clamp member 67 is composed of a belt-like portion 67a and a fastening portion 67b provided with a screw. The belt-like portion 67a is wound around the fixing portion 60b via the urethane sheet 64a, and the fastening portion 67b. The fixing part 60b is fixed to the housing 62 by tightening the belt-like part 67a. Further, the urethane sheet 64a and the housing 62 are sealed by O-rings 68a and 68b that are spaced apart from each other.

  Further, as shown in FIG. 11, an oval communication hole 69 penetrating vertically is formed on the front and rear of the portion of the second arm 20 where the motor 34 is installed, and the left portion is spaced. A substantially elliptical communication hole 69a is formed in which the portions facing each other are wider than the opposite portions. The total area in plan view of the communication hole 69 and the communication hole 69a is the area in plan view of the portion between the inner peripheral surface of the insertion hole portion 31a and the outer peripheral surface of the relay shaft 32b and the inner peripheral surface of the connecting portion 58c. It is set to be the same as or slightly larger than the area in plan view of the portion between the outer peripheral surface of the spline shaft 32a.

  For this reason, when the operating shaft 32 is raised, the lower bellows-like member 60 contracts and the air in the lower bellows-like member 60 passes through the communication holes 69 and 69 a from the cylindrical member 58 and enters the cover 31. At the same time, the upper bellows-like member 50 extends and part of the air in the cover 31 passes through the insertion hole 31a and enters the upper bellows-like member 50. When the operating shaft 32 is lowered, the upper bellows-like member 50 contracts and the air in the upper bellows-like member 50 passes through the insertion hole 31a and enters the cover 31. At the same time, the lower bellows-like member 60 extends and a part of the air in the cover 31 passes through the communication holes 69, 69 a and enters the tubular member 58. Further, the lower bellows-like member 60 extends from the tubular member 58. Get inside. Thus, when the operating shaft 32 moves up and down, the air flowing through the lower bellows-like member 60, the cylindrical member 58, and the cover 31 passes around the motor 34 and the speed reducer 35, and The speed reducer 35 is cooled.

  Although not shown, a hand is attached to the lower part of the coupling shaft 32d via an adapter. A work tool such as a tool, a work device such as a chuck, a work arm, and a suction device, a sensor, and the like are attached to the hand. Further, a part of the wiring etc. 16 in the case 11 or the wiring passing through the flexible tube 15 is connected to the motors 12, 22, 34, 44, etc., and the remaining wiring etc. 16 is further connected to other connection wirings or It is connected to a working device or sensor attached to the hand via a connecting pipe. The distal end of the flexible tube 15 is fixed to the upper surface of the right side portion of the cover 31 by an attachment member 15b, and the wiring 16 and the like are connected to other connection wiring and connection piping in the cover 31.

  Further, a part of the wirings 16 and 17 are connected to a control device (not shown) and a power source, and each device provided in the SCARA robot A operates according to the control of the control device. Further, the exhaust joint 17a of the base portion 10 is connected to a pipe that passes through the flexible tube 15 and communicates with the cover 31. When pressure fluctuation occurs in the cover 31, air is released from the exhaust joint 17a. By doing so, the pressure in the cover 31 is made constant. In addition, when a pressure fluctuation occurs in the cover 31, the pressure fluctuation is eliminated by passing air through the flexible tube 15.

  When the SCARA robot A configured as described above is operated as a component mounting machine for mounting electronic components on a substrate, for example, a member such as a substrate on which electronic components are mounted is installed at a predetermined location, Prepare electronic components in place. Further, devices such as a suction device and a sensor are attached to the lower hand of the operating shaft 32, and corresponding wiring and piping are connected to these devices. Then, the operation of the SCARA robot A is started by operating a switch or the like. As a result, the first arm 18 rotates on the horizontal plane about the rotation shaft 12 b of the motor 12 with respect to the base portion 10, and the second arm 20 rotates with respect to the first arm 18 and the rotation shaft 22 b of the motor 22. Is rotated on a horizontal plane to move the operating shaft 32 to an electronic component installation location.

  Next, by the operation of the motors 34 and 44, the suction device at the lower end of the operating shaft 32 is lowered, and the electronic device can be sucked from a predetermined direction by rotating around the axis. In this state, the electronic device is attracted to the suction device by the operation of the suction device. Next, the operation of the motor 44 raises the suction device, and the operation of the motors 12 and 22 causes the first arm 18 to rotate relative to the base portion 10 and the second arm 20 to rotate relative to the first arm 18. The apparatus moves above a predetermined position on the substrate. Next, the suction device is lowered by the operation of the motors 34 and 44, and the electronic component is positioned at the set position of the substrate by rotating around the axis. In this state, the suction of the electronic component by the suction device is released, and the electronic component is mounted on the substrate. By repeating this operation, a plurality of electronic components are sequentially mounted on the substrate.

  When the SCARA robot A is operated, the upper bellows-like member 50 and the lower bellows-like member 60 are operated in a state in which the periphery of the portion protruding from the cover 31 and the cylindrical member 58 of the operating shaft 32 is sealed. The shaft 32 expands and contracts as the shaft 32 moves up and down. Therefore, external dust and dust are prevented from entering the SCARA robot A, and oil droplets and dust in the SCARA robot A are prevented from scattering to the outside. Further, the motor 34 and the speed reducer 35 are cooled by the air flow generated between the upper bellows-like member 50 and the lower bellows-like member 60 as the operating shaft 32 is moved up and down, and maintain an appropriate operating state.

  As described above, in the SCARA robot A according to the present embodiment, the upper bellows-like member 50 is provided on the upper portion of the operating shaft 32 and the lower bellows-like member 60 is provided on the lower portion of the operating shaft 32. The inside of the shaped member 58 is sealed from the outside. The inside of the upper bellows member 50 and the inside of the cover 31 are communicated with each other through the insertion hole 31a of the cover 31, and the inside of the lower bellows member 60 and the inside of the tubular member 58 are connected with the connecting portion 58c of the tubular member 58. And communicate with. Further, the inside of the cover 31 and the inside of the cylindrical member 58 are communicated with each other through communication holes 69 and 69 a provided in the second arm 20. For this reason, the operating shaft 32 can be moved up and down in a state where dust and the like are prevented from entering and leaving between the inside and the outside of the SCARA robot A.

  Further, the motor 34 and the speed reducer 35 of the rotating device 33 are disposed between the upper bellows-like member 50 and the lower bellows-like member 60, and in this portion, particularly large air is generated when the operating shaft 32 is raised and lowered. The flow of Since the motor 34 and the speed reducer 35 are efficiently cooled by this air flow, it is prevented that the motor 34 and the speed reducer 35 are overheated and the operating efficiency is lowered or easily damaged. Further, an upper bellows-like member 50 and a lower bellows-like member 60 are provided above and below the operating shaft 32, and the upper bellows-like member 50 and the lower bellows-like member 60 are communicated with the inside of the cover 31 and the cylindrical member 58, respectively. Therefore, even if the operating shaft 32 moves up and down, the volume of the entire SCARA robot A does not change and pressure fluctuation does not occur. This makes it difficult for the upper bellows-like member 50 and the lower bellows-like member 60 to be damaged or deteriorated.

  Further, a rotation sealing mechanism including a bearing 51, housings 52 and 53, an end face seal 53d, and the like is provided between the fixed portion 50a of the upper bellows-like member 50 and the connecting shaft 32c constituting the upper end portion of the operating shaft 32. The upper bellows-like member 50 is prevented from rotating even when the operating shaft 32 rotates in the direction around the axis. Similarly, a rotary seal mechanism including a bearing 61, housings 62 and 63, an end face seal 63e, and the like is provided between the fixed portion 60b of the lower bellows-like member 60 and the connecting shaft 32c constituting the lower end portion of the operating shaft 32. ing. For this reason, it is possible to prevent the upper bellows-like member 50 and the lower bellows-like member 60 from being twisted and to prevent the upper bellows-like member 50 and the lower bellows-like member 60 from being damaged due to repeated twists.

  Further, the portion of the operating shaft 32 that protrudes from the cover 31 and the cylindrical member 58 is constituted by an aluminum relay shaft 32b and steel coupling shafts 32c and 32d, so that the processing accuracy is required and the spline is expensive. The shaft 32a can be shortened. Further, the relay shaft 32b and the connecting shaft 32d can be attached to and detached from the spline shaft 32a, and the connecting shaft 32c can be attached to and detached from the relay shaft 32b. In this case, only the damaged member can be replaced without replacing the entire operation shaft 32. Note that the configuration of the portion excluding the upper bellows-like member 50 and the lower bellows-like member 60 of the SCARA robot B shown in FIG. 2 is slightly different from that of the SCARA robot A. The description is omitted. In the SCARA robot B, the insertion hole 31 a of the cover 31 is closed with a seal 78.

(Second Embodiment)
12 and 13 show a SCARA robot C according to the second embodiment of the present invention. This SCARA robot C is a modification of the arrangement of wiring and piping 70 (hereinafter referred to as wiring etc. 70) connected to the wiring 16 extended through the flexible tube 15 in the SCARA robot A described above. The portions other than the mounting structure of the wiring 70 and the like are the same as the SCARA robot A. Therefore, the same parts are described with the same reference numerals.

  In this SCARA type robot C, the wiring etc. 70 extends from the right side portion where the upper surface of the cover 31 is lowered toward the upper end of the connecting shaft 32c. It is fixed by a connecting member 71 comprising a wiring connector and a pipe joint provided on the upper surface. The base end portion of the wiring etc. 70 is connected to the corresponding one of the wiring etc. 16 extending through the flexible tube 15 in the cover 31.

  Further, the central portion in the left-right direction of the front and rear sides of the second arm 20 extends along the right edge of the portion where the upper surface of the cover 31 is raised, and the upper portion is higher than the upper surface of the cover 31. A U-shaped stay 72 is provided. A plurality of screw insertion holes 72a are formed in the upper portion of the stay 72 at a predetermined interval. The wiring 70 and the like are arranged along a portion extending vertically above the front portion of the stay 72, and are fixed to the screw insertion hole 72a of the stay 72 with a plurality of nylon clamps 73 and screws 73a at intervals. .

  A tip side portion of the wiring 70 or the like extends downward from the lower end of the operating shaft 32 through the inside of the operating shaft 32. Further, as shown in FIG. 14, a fixing stay 74 is attached to the upper surface of the housing 53 provided at the upper end of the operating shaft 32, and the wiring etc. 70 is connected to the upper surface of the housing 53 by the stay 74. It is fixed to. The stay 74 is configured by an L-shaped member including a horizontal piece 74a and a vertical piece 74b each having a plurality of screw insertion holes formed at intervals. A plurality of screw holes are formed on the upper surface of the housing 53. The stay 74 is disposed with the horizontal piece 74a positioned on the upper surface of the housing 53, and is fixed to the housing 53 with a screw 74c.

  The wiring 70 is fixed to the vertical piece 74b by two nylon clamps 75 and two screws 75a. Further, the length of the portion of the wiring 70 between the connecting member 71 and the stay 74 is such that the housing 53 is positioned at the upper end of the moving range shown in FIG. 12 and the moving range shown in FIG. In consideration of the stroke between the time when the actuator shaft 32 is located at the lower end of the shaft and the twist when the actuator shaft 32 rotates around the axis, the length is set so that the actuator shaft 32 can be followed and no slack occurs. Has been.

  Further, as shown in FIG. 15, a hand 76 a is attached to the coupling shaft 32 d constituting the lower part of the operating shaft 32 via an adapter 76. A work tool such as a tool, a work device such as a chuck, a work arm, and a suction device, and a sensor 76b are attached to the hand 76a. The wiring 70 or the like extending through the operation shaft 32 is connected to a work device or a sensor 76b attached to the hand 76a. Note that the length of the portion between the lower end portion of the connecting shaft 32d and the hand 76a or the sensor 76b in the wiring 70 or the like does not need to be provided with a margin, and is set to a minimum length. Further, the wiring etc. 70 are connected to the wiring etc. 16 in the cover 31. The rest of the configuration of the SCARA robot C is the same as that of the SCARA robot A described above.

  In the SCARA type robot C configured in this way, the wiring etc. 70 are arranged in the operating shaft 32. Therefore, even if the second arm 20 swings vigorously during the operation of the SCARA type robot C, the wiring etc. There is no obstacle to the movement of the two arms 20. The other functions and effects of the SCARA robot B are the same as those of the SCARA robot A described above.

  The SCARA robot according to the present invention is not limited to the above-described embodiments, and can be implemented with appropriate modifications. For example, in the above-described embodiment, the SCARA robots A and C are configured as dust- and drip-proof SCARA robots using the end surface seals 53d and 63e. It can also be a SCARA robot. In the case of a SCARA robot with a clean specification, a so-called labyrinth structure that prevents the leakage by its resistance is formed by removing the end face seals 53d and 63e that may generate dust, and forming the passage to be folded. And dust is prevented from being released to the outside.

  Furthermore, in order to reduce dust generation, the seal provided between the inner ring and the outer ring of the bearing can be made non-contact or this seal can be removed. Even in this case, the inside of the cover 31, the cylindrical member 58, the upper bellows-like member 50, and the lower bellows-like member 60 is at a negative pressure due to suction, so that dust is prevented from being discharged to the outside. Further, by omitting the end face seals 53d and 63e, it is possible to reduce friction when the housings 52 and 62 rotate.

  Furthermore, in the embodiment described above, the cover member is constituted by the cover 31 and the cylindrical member 58, but one of these can be omitted. In this case, the rotating device 33 and the lifting device 40 are installed inside the cover member made up of the cover 31 or the cylindrical member 58. When the cover 31 is omitted, the upper insertion hole is configured by the mounting hole 25, and when the cylindrical member 58 is omitted, the lower insertion hole is configured by the mounting hole 25. Further, the communication holes 69, 69a provided in the second arm 20 may be omitted, and a communication hole may be formed by providing a gap through which air can pass between the mounting hole 25 and the motor 34. . Furthermore, the configuration of other parts of the SCARA robot according to the present invention can be changed as appropriate within the technical scope of the present invention.

  DESCRIPTION OF SYMBOLS 20 ... 2nd arm, 25 ... Mounting hole, 31 ... Cover, 31a ... Insertion hole part, 32 ... Operating shaft, 32a ... Spline shaft, 32b ... Relay shaft, 32c ... Connecting shaft, 34, 44 ... Motor, 35 ... Reducer, 50 ... Upper bellows-like member, 51, 61 ... Bearing, 52, 53, 62, 63 ... Housing, 53d, 63e ... End face seal, 58 ... Cylindrical member, 58c ... Connecting part, 60 ... Lower bellows-like Member, 69, 69a ... communication hole, A, C ... SCARA type robot.

Claims (8)

A SCARA robot that moves its operating axis in the horizontal direction,
A cover member covering a side of the operating shaft;
A rotation motor for rotating the operating shaft;
An upper bellows-like member which is arranged on the upper part of the cover member and moves up and down in conjunction with the operating shaft;
A lower bellows-like member that is disposed at a lower portion of the cover member and moves up and down in conjunction with the operating shaft;
The cover member and the upper bellows-like member, and the cover member and the lower bellows-like member communicate with each other,
The rotation motor is disposed between the upper bellows-like member and the lower bellows-like member,
The operating shaft includes a spline shaft driven by the rotation motor, and an extension shaft that is detachably connected to an upper end of the spline shaft and protrudes outside the cover member.
The extension shaft is detachably connected to a relay shaft that extends through the upper insertion hole formed in the upper surface of the cover member and extends upward from the cover member, and an upper end of the relay shaft. A SCARA robot comprising a connecting shaft to which an upper end of the upper bellows-like member is fixed . Between the pre-SL upper bellows member and the lower bellows-like member, and the between the rotating motor and the actuating shaft, the speed reducer for transmitting to said actuating shaft by decelerating the rotation speed of the rotating motor The SCARA robot according to claim 1, wherein the robot is installed.   The upper bellows-like member is arranged on the outer periphery of the working shaft, and the working shaft can be rotated with respect to the upper bellows-like member between the upper end portion of the upper bellows-like member and the upper end portion of the working shaft. The SCARA robot according to claim 1 or 2, further comprising a rotary seal mechanism that seals between an upper end portion of the upper bellows-like member and an upper end portion of the operating shaft.   The lower bellows-like member is arranged on the outer periphery of the working shaft, and the working shaft can be rotated with respect to the lower bellows-like member between the lower end portion of the lower bellows-like member and the lower end portion of the working shaft. The SCARA robot according to any one of claims 1 to 3, further comprising a rotary seal mechanism that seals between a lower end portion of the lower bellows-like member and a lower end portion of the operating shaft. The SCARA robot according to any one of claims 1 to 4 , wherein the operating shaft is formed in a cylindrical shape. With movably supporting said actuation shaft, an arm forming a space between said cover member, said forming an upper through hole in the upper part of the space forming part consisting of the arm and the cover member The SCARA robot according to any one of claims 1 to 5 , wherein a lower insertion hole is formed in a lower portion, and the operating shaft is inserted into the upper insertion hole and the lower insertion hole. A mounting hole and a communication hole penetrating up and down are formed in the arm, the cover member is disposed above and below the arm across the mounting hole and the communication hole, and the operating shaft is mounted on the mounting The SCARA robot according to claim 6 , wherein the SCARA robot is inserted into the hole and air is allowed to flow between the upper part and the lower part of the cover member through the communication hole. The cross-sectional area of the portion through which the air flows in the communication hole, the cross-sectional area of the portion through which the air flows between the inner peripheral surface of the upper insertion hole and the outer peripheral surface of the operating shaft, The SCARA robot according to claim 7 , wherein the SCARA robot is larger than a cross-sectional area of a portion where air flows between the outer peripheral surface of the operating shaft.