JP2013220488A - Scara robot and method for manufacturing the scara robot - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a SCARA robot having the high degree of freedom in designing.SOLUTION: The SCARA robot 1 has: a base substrate 13; a first arm 5 connected to the base substrate 13 rotatably around a first axis A1; and a second arm substrate 37 connected to the first arm 5 rotatably around a second axis A2 in parallel with the first axis A1 and away from the first axis A1. A first speed reducer 17 has: a first speed reducer body 29 which is fixed to the base substrate 13 for decelerating revolution of a first electric motor 15; and a first output shaft 31 pivoted to the first speed reducer body 29 rotatably around the first axis A1 for transferring the decelerated revolution to the first arm 5. The first arm 5 pinches the first output shaft 31 in a radial direction thereof.

Description

  The present invention relates to a SCARA robot and a manufacturing method thereof.

  A base, a first arm rotatable about a first axis (generally a vertical axis) with respect to the base, and a second arm rotatable about a second axis parallel to the first axis with respect to the first arm There is known a SCARA robot having (for example, Patent Document 1).

  The specific configuration of the SCARA robot of Patent Document 1 is as follows. The base includes a casing-shaped base base, a first electric motor housed in the base base, and a first speed reducer that decelerates the rotation of the first electric motor and transmits it to the first arm. The second arm includes a housing-like second arm base, a second electric motor housed in the second arm base, a second speed reducer that reduces the rotation of the second electric motor and transmits it to the first arm. have. The first arm is constituted by a plate-like member orthogonal to the first axis and the second axis, and an output part (rotating part) of the first reduction gear is fixed to one main surface of the first arm and the other main part. The output portion of the second speed reducer is fixed to the surface.

  In such a SCARA robot, the output part of the speed reducer and the first arm are fixed by screwing a bolt inserted into the first arm in the axial direction of the output part into a female screw part provided in the output part of the speed reducer. Is done by letting

JP 2007-237316 A

  Various inconveniences arise in the fixing method of the output part of the reduction gear and the first arm as described above. For example, although the first reduction gear and the second reduction gear are fixed to the main surfaces opposite to each other in the first arm, the first shaft and the second shaft are arranged for the convenience of inserting the bolt into the first arm. It is difficult to arrange the parts so as to partially overlap in the axial direction. As a result, for example, it is difficult to configure a SCARA robot in which the distance between the first and second axes is shortened.

  An object of the present invention is to provide a SCARA robot having a high degree of design freedom and a manufacturing method thereof.

  A SCARA robot according to a first aspect of the present invention includes a base base, a first arm base coupled to the base base so as to be rotatable about a first axis, and the first arm base with respect to the first arm base. A second arm base coupled to be rotatable about a second axis parallel to one axis and spaced from the first axis; a first electric motor held by the base base; and fixed to the base base, A first transmission main body that shifts the rotation of one electric motor; and a first output that is pivotally supported by the first transmission main body so as to be rotatable about the first shaft and that transmits the rotated rotation to the first arm base. A first transmission having a shaft, a second electric motor held by the second arm base, a second transmission main body fixed to the second arm base and shifting the rotation of the second electric motor, The second transmission body is pivotally supported around the second shaft. A second transmission having a second output shaft that transmits the rotated rotation to the first arm base, wherein the first arm base is configured to support the first output shaft and the second output shaft. At least one is clamped in the radial direction.

  Preferably, the second arm base is located on the opposite side of the base base with respect to the first arm base in the axial direction of the second axis, and the first arm base is the first output shaft. And the second output shaft is sandwiched in the radial direction, and the first transmission and the second transmission are partially overlapped when viewed in a direction parallel to the first shaft and the second shaft. Yes.

  Preferably, the first arm base includes an intermediate member and a first member fixed to the intermediate member so as to sandwich the first output shaft with the intermediate member in the radial direction.

  Preferably, the intermediate member is formed with a first notch for housing the first member on the first transmission side in the axial direction of the first shaft.

  Preferably, at least one of the intermediate member and the first member is formed with a groove extending along the first shaft and into which the first output shaft is fitted.

  Preferably, the first arm base is supported with respect to the base only by the first speed reducer.

  A SCARA robot according to a second aspect of the present invention includes a base base, a first arm base coupled to the base base so as to be rotatable about the first axis with respect to the base base, and parallel to the first axis. In the axial direction of the second axis that is spaced from the first axis, it is located on the opposite side of the base base with respect to the first arm base, and is rotatable about the second axis with respect to the first arm base. A connected second arm base, a first electric motor held by the base base, a first transmission for shifting the rotation of the first electric motor and transmitting it to the first arm base, and the second arm base A second electric motor held by the second electric motor, and a second transmission for shifting the rotation of the second electric motor and transmitting it to the first arm base, wherein the first transmission and the second transmission are: A portion is overlapped when viewed in a direction parallel to the first axis and the second axis. To have.

  A method for manufacturing a SCARA robot according to the present invention includes a base base, a first arm base coupled to the base base so as to be rotatable about a first axis, and the first axis with respect to the first arm base. A second arm base connected to the first arm base so as to be rotatable about a second axis parallel and spaced from the first axis, a first electric motor held by the base base, and fixed to the base base A first transmission main body for shifting the rotation of the first electric motor; and the first transmission main body, which is pivotally supported by the first transmission main body so as to be rotatable about the first axis, and transmits the rotated rotation to the first arm base body. A first transmission having a first output shaft, a second electric motor held by the second arm base, and a second transmission main body fixed to the second arm base and shifting the rotation of the second electric motor And rotate around the second shaft on the second transmission body. A SCARA robot manufacturing method comprising: a second transmission having a second output shaft that is pivotally supported and that transmits a rotated rotation to the first arm base, wherein the base is the first arm base. The material is divided into an intermediate member, a first member, and a second member, and the intermediate member and the first member are sandwiched between the intermediate member and the first member in the radial direction of the first output shaft. The intermediate member and the second member are fixed so that the second output shaft is sandwiched between the intermediate member and the second member in the radial direction.

  According to the present invention, the degree of freedom in design increases.

The side view which shows the external appearance of the SCARA robot which concerns on embodiment of this invention. The perspective view which shows the principal part of the SCARA robot of FIG. The perspective view which shows the 1st arm of the SCARA robot of FIG. The perspective view explaining the fixing method of the reduction gear and the 1st arm in the SCARA robot of FIG.

  FIG. 1 is a side view showing an appearance of a SCARA robot 1 according to an embodiment of the present invention.

  The SCARA robot 1 may be installed in an appropriate direction at an appropriate position such as a horizontal placement surface, an inclined placement surface, a wall surface, or a ceiling, but in the following, for convenience of explanation, the SCARA robot 1 is installed on the horizontal placement surface. It will be described as being done. Further, an orthogonal coordinate system xyz may be defined for the stationary part (base 3) of the SCARA robot 1 and the coordinates may be referred to as appropriate.

  The SCARA robot 1 is connected to a base 3, a first arm 5 connected to the base 3 so as to be rotatable about a first axis A1, and a first arm 5 connected to be rotatable about a second axis A2. The second arm 7, the working shaft 9 that can move in the axial direction of the third axis A 3 with respect to the second arm 7 and that can rotate about the third axis A 3, and the second arm 7 from the base 3. And a duct 11 extending to the front.

  The first axis A1, the second axis A2, and the third axis A3 are parallel to each other. The first axis A1, the second axis A2, and the third axis A3 are, for example, axes that extend vertically when the SCARA robot 1 is placed on a horizontal placement surface. The inter-axis distance between the first axis A1 and the second axis A2 and the inter-axis distance between the second axis A2 and the third axis A3 are appropriately set according to the application of the SCARA robot 1 or the like.

  In the SCARA robot 1, a work device (not shown) that performs various work is attached to the lower end 9 a of the work shaft 9. The work device is, for example, a robot hand or a tool. The SCARA robot 1 performs work by moving the work device to an appropriate position by the first arm 5, the second arm 7, and the work shaft 9.

  FIG. 2 is a perspective view showing a cross section of the main part of the SCARA robot 1.

  The base 3 includes a housing-like base base 13 (see also FIG. 1), a first motor 15 accommodated in the base base 13, and a first speed that decelerates the rotation of the first motor 15 and transmits it to the first arm 5. 1 reduction gear 17. In addition, the base 3 includes, for example, a power supply device and a control device (not shown).

  The base substrate 13 is formed of, for example, a metal such as aluminum, and is generally formed in a rectangular parallelepiped. The bottom surface of the base substrate 13 is fixed to an installation surface such as a floor surface.

  The first electric motor 15 is a rotary electric motor. The first motor 15 may be a DC motor, an AC motor, an induction motor, or a synchronous motor.

  The first electric motor 15 has an electric motor main body 19 and an output shaft 21 extending from the electric motor main body 19. The motor body 19 includes a housing 23 that supports the output shaft 21, a field 25 that is fixed to one of the housing 23 and the output shaft 21 (the housing 23 in the present embodiment), the housing 23, and the output shaft. And the armature 27 fixed to the other (the output shaft 21 in this embodiment).

  The housing 23 is fixed to the base substrate 13 indirectly and / or directly by being fixed to the first speed reducer 17 fixed to the base substrate 13. The output shaft 21 is located on the first axis A1, for example.

  The first speed reducer 17 includes a first speed reducer main body 29 and a first output shaft 31 extending from the first speed reducer main body 29. The first reduction gear main body 29 includes a housing 33 that supports the first output shaft 31 and a gear train 35 (the details are omitted in FIG. 2) housed in the housing 33. The housing 33, the gear train 35, and the first output shaft 31 are made of, for example, metal.

  The housing 33 is fixed to the base substrate 13 by, for example, a bolt (not shown). The first output shaft 31 is located on the first axis A <b> 1 and is fixed to the first arm 5. The gear train 35 receives the rotation of the output shaft 21 of the first electric motor 15, decelerates the rotation, and transmits it to the first output shaft 31. As a result, the first arm 5 rotates around the first axis A <b> 1 with respect to the base 3.

  The first arm 5 is configured as a member that is supported by the base 3 and supports the second arm 7. That is, the first arm 5 is constituted only by the first arm base. The first arm 5 is made of a metal such as aluminum. The configuration of the first arm 5 will be described later.

  The second arm 7 has a housing-like second arm base 37 (see also FIG. 1), a second electric motor 39 accommodated in the second arm base 37, and the first electric motor 39 by reducing the rotation of the second electric motor 39. A second reduction gear 41 that transmits to the arm 5 is included. In addition, the second arm 7 is configured to rotate, for example, an electric motor and a speed reducer (not shown) for moving the work shaft 9 in the axial direction of the third axis A3 and the work shaft 9 about the third axis A3. (Not shown) and a reduction gear.

  The second arm base 37 includes a plate-like base 43 that is orthogonal to the second axis A2 and the third axis A3, and a box-shaped cover 45 (FIG. 1) that covers the base 43. These are made of a metal such as aluminum.

  The second electric motor 39 is a rotary electric motor. The second motor 39 may be a DC motor, an AC motor, an induction motor, or a synchronous motor.

  The second electric motor 39 has an electric motor main body 47 and an output shaft 49 extending from the electric motor main body 47. The electric motor main body 47 includes a housing 51 that supports the output shaft 49, a field 53 that is fixed to one of the housing 51 and the output shaft 49 (the housing 51 in the present embodiment), the housing 51, and the output shaft. The armature 55 is fixed to the other of 49 (the output shaft 49 in this embodiment).

  The casing 51 is fixed to the base 43 indirectly and / or directly by being fixed to the second speed reducer 41 fixed to the base 43. The output shaft 49 is located on the second axis A2, for example.

  The second speed reducer 41 has a second speed reducer main body 57 and a second output shaft 59 extending from the second speed reducer main body 57. The second speed reducer main body 57 includes a housing 61 that supports the second output shaft 59 and a gear train 63 (details thereof are omitted in FIG. 2) housed in the housing 61. The housing 61, the gear train 63, and the second output shaft 59 are made of, for example, metal.

  The housing 61 is fixed to the base 43 by, for example, a bolt (not shown). The second output shaft 59 is located on the second axis A <b> 2 and is fixed to the first arm 5. The gear train 63 receives the rotation of the output shaft 49 of the second electric motor 39, decelerates the rotation, and transmits it to the second output shaft 59. Accordingly, the second arm 7 rotates around the second axis A2 with respect to the first arm 5.

  The work shaft 9 (FIG. 1) is, for example, a ball screw spline shaft extending in a direction along the third axis A3. The work shaft 9 is made of a metal such as aluminum, for example.

  The duct 11 is a hollow member formed of, for example, a flexible resin, and communicates the inside of the base base 13 and the inside of the second arm base 37. In the duct 11, for example, a cable for supplying electric power from the power supply device in the base base 13 to the second electric motor 39 in the second arm base 37 is provided, although not particularly illustrated.

  The first reducer 17 and the second reducer 41 are partially overlapped when viewed in the z direction. Specifically, for example, the end surface on the side where the first output shaft 31 of the housing 33 of the first reduction gear 17 extends and the side of the side where the second output shaft 59 of the housing 61 of the second reduction gear 41 extends. The end surface partially overlaps. Furthermore, the gear train of one speed reducer and the end surface on the side from which the output shaft of the housing of the other speed reducer extends partially overlap. In FIG. 2, the output shaft of one speed reducer does not overlap the housing of the other speed reducer, but may overlap.

  FIG. 3 is a perspective view of the first arm 5. FIG. 4 is a perspective view illustrating a method of fixing the first reduction gear 17 and the second reduction gear 41 to the first arm 5.

  The first arm 5 as a whole is formed in a thick plate shape or a short column shape. The planar shape (the shape seen in the z direction) is, for example, an oval shape. The oval shape may be elliptical, or may be semicircular at both ends and rectangular at the center (the shape of the present embodiment). Further, for example, the oval has one end formed by a semicircle centered on the first axis A1 and the other end formed by a semicircle centered on the second axis A2.

  Moreover, the 1st arm 5 has a member of the shape which divided | segmented the columnar shape into three. That is, the first arm 5 has an intermediate member 65, a first member 67 (FIG. 3), and a second member 69.

  The intermediate member 65 has a generally columnar shape, in which a first notch 65a is formed on the negative side in the z direction and on the first axis A1 side, and a second notch 65b on the positive side in the z direction and on the second axis A2 side. The shape is formed. In other words, the intermediate member 65 includes a substantially rectangular parallelepiped center portion 65c, a first flange 65d projecting from the positive side in the z direction of the central portion 65c and the first axis A1, and a negative portion in the z direction of the central portion 65c. And a second flange 65e protruding from the second axis A2 side.

  The first notch 65a (first flange 65d) is formed, for example, in a semicircular shape centered on the first axis A1 in plan view, and the depth (thickness of the first flange 65d) is constant. It is said that. Similarly, the second notch 65b (second flange 65e) is formed, for example, in a semicircular shape centered on the second axis A2 in plan view, and its depth (the thickness of the second flange 65e). ) Is assumed to be constant.

  The first member 67 is generally formed in a shape that fits into the first notch 65a. That is, the first member 67 is generally formed in a columnar shape having a semicircular planar shape. Similarly, the second member 69 is generally formed in a shape (semicircular column shape) that fits into the second notch 65b.

  The first member 67 (first notch 65a) and the second member 69 (second notch 65b) have the same shape, but the dimensions (for example, the thickness in the z direction and the dimensions of details described later) are the same. , May be different from each other.

  The intermediate member 65 and the first member 67 hold a first output shaft 31 (FIG. 2) of the first speed reducer 17 therebetween, and a plurality of bolts 71 (one for the second member 69 in FIG. 4). Only fixed to each other). Further, the intermediate member 65 and the second member 69 are fixed to each other by a plurality of bolts 71 while sandwiching the second output shaft 59 of the second reduction gear 41 therebetween. Specifically, it is as follows.

  A groove 65f extending along the second axis A2 is formed in the central portion 65c of the intermediate member 65 on the second notch 65b side. The second member 69 has a groove 69f (FIG. 3) extending along the second axis A2 on the intermediate member 65 side. Each of the cross-sectional shapes (the shapes viewed in the z direction) of the grooves 65f and 69f is, for example, a semicircle centered on the second axis A2.

  The second output shaft 59 of the second speed reducer 41 is fitted in the groove 65f and the groove 69f, respectively, and is accommodated in a hole formed by the groove 65f and the groove 69f. However, the groove 65f and the groove 69f are formed to be slightly smaller than a semicircle, and the intermediate member 65 and the second member 69 are in the sandwiched direction (x direction) in the state where the second output shaft 59 is sandwiched. They are separated from each other through a slight gap.

  Then, in the x direction, the bolt 71 is inserted into the hole 69h formed in the second member 69 and screwed into the female screw portion 65h (FIG. 4) formed in the intermediate member 65, whereby the intermediate member 65 is inserted. And the second member 69 are fixed to each other. The second output shaft 59 is fastened by the intermediate member 65 and the second member 69, and is fixed to these members in the x direction and the y direction. The movement of the second output shaft 59 in the z direction relative to the intermediate member 65 and the second member 69 and the rotation around the second axis A2 are regulated by the frictional force generated by the second output shaft 59 being fastened to these members. .

  In addition, the number and arrangement position of the bolts 71 may be set as appropriate. Preferably, the bolts 71 are disposed on both sides of the second axis A2 and are disposed in the z direction at 2 or more (four or more in total). The hole 69h is configured to be able to accommodate the bolt head of the bolt 71.

  A concave portion 65g is formed in the central portion 65c of the intermediate member 65 on the second notch 65b side and the positive side in the z direction. The second member 69 has a recess 69g on the intermediate member 65 side and on the positive side in the z direction. The planar shape (the shape viewed in the z direction) of each of the recess 65g and the recess 69g is, for example, generally a semicircle centered on the second axis A2.

  The casing 33 of the second speed reducer 41 is housed in a circular recess formed by the recess 65g and the recess 69g at a part of the side from which the second output shaft 59 extends. As a result, the thickness of the first arm 5 is ensured and the strength of the first arm 5 is improved, while the accommodation space for the second reduction gear 41 is secured, and the SCARA robot 1 as a whole can be reduced in size. it can. In addition, such a recessed part does not need to be formed.

  The housing 33 of the second speed reducer 41 is separated from the first arm 5 so as to be movable around the second axis A2 with respect to the first arm 5. Specifically, the recess composed of the recess 65g and the recess 69g is formed to be slightly larger than the housing 33, whereby the intermediate member 65 and the second member 69 are arranged in the x and y directions. It is away from. The second output shaft 59 of the second speed reducer 41 is formed longer than the depth obtained by subtracting the depths of the recess 65g and the recess 69g from the depth (z direction) of the second notch 65b, and the tip thereof. Is in contact with the second flange 65e of the intermediate member 65 in the z direction, whereby the housing 33 is positioned so as to be separated from the bottom surfaces of the recess 65g and the recess 69g.

  The fixing of the second speed reducer 41 to the first arm 5 has been described above. However, the fixing of the first speed reducer 17 to the first arm 5 is such that the direction of each member and each part is the same as that of the second speed reducer 41 side. Except for the reverse on the machine 17 side, it is the same, and the description is omitted.

  The base base 13 and the first arm 5 are connected only by the first speed reducer 17, and the first arm 5 and the second arm base 37 are connected only by the second speed reducer 41. It has been broken. The support of the first arm 5 by the base base 13 is performed only via the first speed reducer 17, and the support of the second arm base 37 by the first arm 5 is supported via the second speed reducer 41. Only done. That is, the 1st reduction gear 17 and the 2nd reduction gear 41 serve as the connection mechanism and the support mechanism. However, in addition to the first reduction gear 17 and the second reduction gear 41, a connection mechanism and / or a support mechanism may be provided.

  The intermediate member 65, the first member 67, and the second member 69 of the first arm 5 are formed by, for example, cutting a base material having the outer shape of the first arm 5 with a metal saw or the like (performing slitting). The recesses (65g, etc.), grooves (65f, etc.), holes (69h, etc.) and female screw parts (65h, etc.) may be formed either before or after the slotting process, and preferably the slotting process. Formed before.

  Thus, a manufacturing method is simplified by forming three members by slitting. Further, each member is cut while being cut by a metal saw or the like, so that the volume in the vicinity of the cut surface is reduced. For example, after forming a hole portion into which the output shaft (59 or the like) of the speed reducer is fitted. If cut, grooves smaller than a semicircle (such as 65f) are naturally formed. That is, when the output shaft is sandwiched between the two members, a gap between the two members necessary for tightening the output shaft with the two members is naturally formed.

  As described above, in this embodiment, the SCARA robot 1 includes the base base 13, the first arm 5 (first arm base) connected to the base base 13 so as to be rotatable about the first axis A 1, and the first The second arm base 37 is connected to the first arm 5 so as to be rotatable about a second axis A2 parallel to the first axis A1 and spaced apart from the first axis A1. The SCARA robot 1 includes a first electric motor 15 held on the base base 13, a second electric motor 39 held on the second arm base 37, a first reduction gear 17, and a second reduction gear 41. doing.

  The first speed reducer 17 is fixed to the base base 13 and is supported by the first speed reducer main body 29 that decelerates the rotation of the first electric motor 15 and the first speed reducer main body 29 so as to be rotatable around the first axis A1. The first output shaft 31 transmits the decelerated rotation to the first arm 5. The second speed reducer 41 is fixed to the second arm base 37 and has a second speed reducer main body 57 that decelerates the rotation of the second electric motor 39, and a shaft that is rotatable around the second axis A2 on the second speed reducer main body 57. A second output shaft 59 that transmits the supported and decelerated rotation to the first arm 5 is provided.

  The first arm 5 holds the first output shaft 31 and the second output shaft 59 in the radial direction. Specifically, the first arm 5 includes an intermediate member 65, a first member 67 fixed to the intermediate member 65 so as to sandwich the first output shaft 31 with the intermediate member 65 in the radial direction, and a second member 67. And a second member 69 fixed to the intermediate member 65 so as to sandwich the output shaft 59 with the intermediate member 65 in the radial direction.

  Therefore, the region on the opposite side of the first arm 5 to the first speed reducer 17 (the positive side in the z direction) overlaps the first speed reducer 17 in the z direction, and the second speed reducer 41 of the first arm 5. It is no longer necessary to arrange a bolt for fixing the output part of the speed reducer to the first arm 5 in the region opposite to (the negative side in the z direction) and overlapping the second speed reducer 41 in the z direction. Thus, effective use of these areas can be achieved. That is, the degree of freedom in design is improved.

  As a result, for example, when the SCARA robot 1 is configured such that the second arm base 37 is positioned on the side opposite to the base base 13 with respect to the first arm 5 in the axial direction of the second axis A2, It is possible to arrange the first reduction gear 17 and the second reduction gear 41 so that a part of the first reduction gear 17 and the second reduction gear 41 overlap each other when viewed in the z direction. It is also possible to realize a SCARA robot having a short distance (distance between axes) from the two axes A2. For example, in a SCARA robot having a maximum payload of about 2 kg, the distance between axes can be made less than 70 mm.

  The intermediate member 65 is formed with a first notch 65a for accommodating the first member 67 on the first speed reducer 17 side in the axial direction of the first axis A1.

  Therefore, workability when attaching the first member 67 to the intermediate member 65 is improved. Moreover, the front-end | tip of the 1st output shaft 31 of the 1st reduction gear 17 can be contact | abutted to the 1st flange 65d, and the contact with the 1st reduction gear main body 29 and the 1st arm 5 can also be prevented reliably. The same effect can be achieved with the second notch 65b.

  The intermediate member 65 is formed with a groove 65j (FIG. 2) extending along the first axis A1 and into which the first output shaft 31 is fitted. The first member 67 extends along the first axis A1. A groove 67j (FIG. 2) in which the first output shaft 31 is fitted is formed.

  Accordingly, a contact area between the first output shaft 31 and the first arm 5 of the first reduction gear 17 is ensured and these are fixed firmly, and the axial center of the first output shaft 31 is set to an intended position. (Centering is done). When the first output shaft 31 is inserted into the hole, the hole needs to be formed slightly larger than the first output shaft 31 so that the first output shaft 31 can be inserted, but the two grooves 65j and 67j sandwiching the first output shaft 31 are required. Therefore, it is not necessary to be formed larger than the output shaft, and it is expected that centering is performed more accurately. The same effect can be obtained with the grooves 65f and 69f for the second output shaft 59 of the second reduction gear 41.

  The present invention is not limited to the above embodiment, and may be implemented in various aspects.

  In the SCARA robot according to the first aspect of the present invention (the SCARA robot holding the output shaft of the speed reducer), the second arm base is opposite to the base base with respect to the first arm base in the axial direction of the second axis. May not be provided (may be provided on the base substrate side). In the case where the second arm base is provided on the opposite side of the base base with respect to the first arm base, the first speed reducer and the second speed reducer are parallel to the first axis and the second axis. When viewed in the z direction (as viewed in the z direction), they may not be arranged so as to partially overlap. When the first reducer and the second reducer do not overlap, only one output shaft of the first reducer and the second reducer is sandwiched between the first arm bases, and the other output shaft is a conventional one. It may be fixed to the first arm base by a method.

  In the SCARA robot according to the second aspect of the present invention (a SCARA robot in which the first speed reducer and the second speed reducer are arranged so as to partially overlap each other when viewed in the z direction), the intermediate member and the first member (Or the second member) may not sandwich the output shaft of the reduction gear. For example, a bolt is inserted into the integrally formed first arm base body having the same outer shape as the first arm 5 of the embodiment from the x direction or the y direction, and the bolt is screwed to the output portion of the speed reducer. May be. However, the reduction gear is not necessarily manufactured by the manufacturer of the SCARA robot, and it is expected that it is difficult to insert a bolt from the side. It is preferable to be like a robot.

  The holding of the output shaft of the reduction gear by the first arm base is not limited to a method of fixing the two members to each other with the output shaft interposed therebetween. For example, the output shaft may be sandwiched between U-shaped members and tightened with bolts or the like.

  The direction in which the output shaft of the speed reducer is clamped by the first arm base is not limited to the direction connecting the first axis and the second axis (the front-rear direction of the first arm). For example, the intermediate member and the first member (or the second member) sandwich the output shaft in a direction perpendicular to the direction connecting the first axis and the second axis (the left and right direction of the first arm). Also good.

  The holding of the output shaft of the speed reducer by the intermediate member and the first member (or the second member) is performed by fixing the intermediate member and the first member to each other by bolts arranged on both sides of the output shaft. It is not limited. For example, on one side of the side of the output shaft, the separation between the intermediate member and the first member may be restricted, and the bolt may be fastened only on the other side. Moreover, it may replace with a volt | bolt and may use a clamping device like a vise or urging means like a spring.

  The boundary surface between the intermediate member and the first member (or the second member) may not be a single plane that passes through the output shaft of the speed reducer. For example, in the embodiment, the first member (or the second member) may have a sector shape having a center angle smaller than or larger than 180 ° with the output shaft of the speed reducer as the center.

  The notch (flange) of the intermediate member may not be provided. That is, the first member and / or the second member may be a member having a thickness equivalent to that of the intermediate member. Further, the notch (flange) may be provided in the first member and / or the second member instead of the intermediate member. However, from the viewpoint of improving workability and improving the strength of the first arm, the notch is preferably provided in the intermediate member.

  When the notch is provided in the intermediate member (or the first member or the second member), the tip of the output shaft of the speed reducer may not contact the flange of the intermediate member. For example, in the speed reducer, the movement in the z direction may be restricted only by the frictional force generated when the output shaft is tightened by the intermediate member and the first member (or the second member). Further, for example, a fitting groove extending around the output shaft and a protrusion fitting into the fitting groove are formed on the inner circumferential surface of the groove (65f or the like) into which the output shaft is fitted and the outer circumferential surface of the output shaft. Thus, the movement in the z direction may be reliably regulated.

  In the embodiment, the connection between the first arm base and the base base is made only by the first speed reducer, and the connection between the first arm base and the second arm base is made only by the second speed reducer. By adjusting the position of the output shaft of the reducer and the first arm base in the z direction (or adjusting the length of the output shaft, etc.), the position adjustment of the first arm base with respect to the base base or the second arm base can be easily performed. Can be done. The fixing method of holding the output shaft by the first arm also has such an effect. In this case, the output shaft may be reliably positioned at an appropriate position with respect to the first arm by providing a plurality of fitting grooves and protrusions as described above in the z direction.

  The intermediate member and the first member (or the second member) may not have a groove (65f or the like) into which the output shaft of the speed reducer is fitted. Further, a groove portion into which the output shaft is fitted may be formed only in one of the intermediate member and the first member (or the second member).

  The intermediate member, the first member, and the second member are not limited to those formed by slitting, and may be formed separately by die casting or formed by cutting.

  In the embodiment, the rotation around the axis of the output shaft of the reduction gear with respect to the first arm is restricted only by the frictional force. However, a key or a key groove is formed on the output shaft, a key groove or a key corresponding to the intermediate member and / or the first member (or the second member) is formed, and these engagements with respect to the first arm of the output shaft You may regulate rotation.

  A speed increaser may be provided instead of the speed reducer. That is, the mechanism for transmitting the rotation of the electric motor to the first arm may be a transmission.

  DESCRIPTION OF SYMBOLS 1 ... Injection device, 5 ... Plunger, 7 ... Cylinder device, 9 ... Hydraulic device, 11 ... Drive device, 13 ... Detachable part, 25 ... Piston rod, 65 ... Nut (driven part), 105 ... Cavity.

Claims (8)

A base substrate;
A first arm base coupled to the base base so as to be rotatable about a first axis;
A second arm base coupled to the first arm base so as to be rotatable about a second axis parallel to the first axis and spaced from the first axis;
A first electric motor held by the base substrate;
A first transmission main body fixed to the base base body for shifting the rotation of the first electric motor, and supported by the first transmission main body so as to be rotatable about the first axis, and the rotation rotated by the first electric motor. A first transmission having a first output shaft that transmits to one arm base;
A second electric motor held by the second arm base;
A second transmission main body fixed to the second arm base and configured to change the rotation of the second electric motor; and a second transmission main body that is rotatably supported around the second axis and is rotated by the second transmission main body. A second transmission having a second output shaft for transmission to the first arm base;
Have
The first arm base is a SCARA robot holding at least one of the first output shaft and the second output shaft in the radial direction. The second arm base is located on the opposite side of the base base with respect to the first arm base in the axial direction of the second axis;
The first arm base sandwiches both the first output shaft and the second output shaft in the radial direction,
The SCARA robot according to claim 1, wherein the first transmission and the second transmission partially overlap each other when viewed in a direction parallel to the first axis and the second axis. The first arm base is
An intermediate member;
The SCARA robot according to claim 1, further comprising: a first member fixed to the intermediate member so as to sandwich the first output shaft with the intermediate member in a radial direction thereof. 4. The SCARA robot according to claim 3, wherein the intermediate member is formed with a first notch that accommodates the first member on the first transmission side in the axial direction of the first shaft. 5. The SCARA robot according to claim 3, wherein at least one of the intermediate member and the first member is formed with a groove extending along the first axis and into which the first output shaft is fitted. The SCARA robot according to any one of claims 1 to 5, wherein the first arm base is supported with respect to the base only by the first speed reducer. A base substrate;
A first arm base coupled to the base base so as to be rotatable about a first axis with respect to the base base;
The axial direction of the second axis parallel to the first axis and spaced from the first axis is located on the opposite side of the first base with respect to the first base, and the first base with respect to the first arm base. A second arm base coupled rotatably about two axes;
A first electric motor held by the base substrate;
A first transmission for shifting the rotation of the first electric motor and transmitting it to the first arm base;
A second electric motor held by the second arm base;
A second transmission for shifting the rotation of the second electric motor and transmitting it to the first arm base;
Have
A SCARA robot in which the first transmission and the second transmission partially overlap each other when viewed in a direction parallel to the first axis and the second axis. A base substrate;
A first arm base coupled to the base base so as to be rotatable about a first axis;
A second arm base coupled to the first arm base for rotation about a second axis parallel to the first axis and spaced from the first axis with respect to the first arm base;
A first electric motor held by the base substrate;
A first transmission main body fixed to the base base body for shifting the rotation of the first electric motor, and supported by the first transmission main body so as to be rotatable about the first axis, and the rotation rotated by the first electric motor. A first transmission having a first output shaft that transmits to one arm base;
A second electric motor held by the second arm base;
A second transmission main body fixed to the second arm base and configured to change the rotation of the second electric motor; and a second transmission main body that is rotatably supported around the second axis and is rotated by the second transmission main body. A second transmission having a second output shaft for transmission to the first arm base;
A method for manufacturing a SCARA robot having
The base material to be the first arm base is cut into an intermediate member, a first member, and a second member,
Fixing the intermediate member and the first member so as to sandwich the first output shaft between the intermediate member and the first member in the radial direction;
A method for manufacturing a SCARA robot, wherein the intermediate member and the second member are fixed so that the second output shaft is sandwiched between the intermediate member and the second member in a radial direction thereof.

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