Motor assembly method, motor, and robot

Abstract

The present invention provides a motor assembly method, a motor, and a robot that enhance the fixing force between the bearing and the case. [Solution] The assembly method for the motor 1 includes the steps of applying adhesive to the notch 16, inserting the bearing 4 into the bearing fixing part 14 and fixing the bearing 4 to the bearing fixing part 14, and fixing the ring member 6 to the ring member fixing part 15.

Description

Technical Field

[0001] The present invention relates to a method for assembling a motor, a motor, and a robot.

Background Art

[0002] For example, in Patent Document 1, in an electric motor of a motor, at least one hole for injecting an adhesive is provided between the outer ring of the anti-load side bearing incorporated in the bearing housing portion of the anti-load side bracket and the bearing housing portion while applying a preload with the repulsive force of an elastic body. By injecting an adhesive into the hole to join the outer ring of the anti-load side bearing and the bearing housing portion, it is possible to prevent bearing creep and extend the bearing life while applying a stable preload to the bearing. A motor is described.

Prior Art Documents

Patent Documents

[0003]

Patent Document 1

Summary of the Invention

Problems to be Solved by the Invention

[0004] However, in the motor described in Patent Document 1, since only the adhesive injected into the hole joins the anti-load side bearing and the bearing housing portion, the contact area for joining the bearing and the housing portion is small, and there is a possibility that the fixing force between the bearing and the housing portion is not sufficient.

Means for Solving the Problems

[0005] A motor assembly method comprising: a rotor having a rotating shaft; a stator positioned with a gap between it and the rotor; a bearing holding the rotating shaft at one end in a first axial direction of the rotating shaft; a case housing the rotor, the stator, and the bearing; and a ring member pressing the bearing toward a second direction opposite to the first direction and fixing it to the case, wherein the case has a bearing fixing portion for fixing the bearing; a ring member fixing portion for fixing the ring member and located toward the first direction of the bearing fixing portion; and a plurality of notches in which the ring member fixing portion is radially cut out such that its diameter is larger than the inner diameter of the bearing fixing portion, and the method includes the steps of applying adhesive to the notches, inserting the bearing into the bearing fixing portion and fixing the bearing to the bearing fixing portion, and fixing the ring member to the ring member fixing portion.

[0006] The motor comprises a rotor having a rotating shaft, a stator positioned with a gap between it and the rotor, a bearing that holds the rotating shaft at one end in a first axial direction of the rotating shaft, a case housing the rotor, the stator, and the bearing, and a ring member that presses the bearing toward a second direction opposite to the first direction and is fixed to the case, wherein the case has a bearing fixing portion for fixing the bearing, a ring member fixing portion for fixing the ring member and located toward the first direction of the bearing fixing portion, and a plurality of notches in which the ring member fixing portion is cut radially so that its diameter is larger than the inner diameter of the bearing fixing portion, the bearing is fixed to the bearing fixing portion by adhesive applied to the notches, and the ring member is fixed to the ring member fixing portion.

[0007] The robot has the motor described above. [Brief explanation of the drawing]

[0008] [Figure 1]A perspective view showing the schematic structure of a motor assembled using the motor assembly method according to the first embodiment. [Figure 2] A plan view of the motor with the ring component removed, as shown in Figure 1. [Figure 3] Cross-sectional view along line AA in Figure 2. [Figure 4] A perspective view of the cross-section along line AA in Figure 2. [Figure 5] A flowchart illustrating the assembly method of the motor according to the first embodiment. [Figure 6] A plan view of the motor shown in Figure 1. [Figure 7] Cross-sectional view along line BB in Figure 6. [Figure 8] A plan view showing the schematic structure of a motor assembled using the motor assembly method according to the third embodiment. [Figure 9] Cross-sectional view along line CC in Figure 8. [Figure 10] A flowchart illustrating the assembly method of the motor according to the third embodiment. [Figure 11] A schematic diagram of a robot having a motor according to the fourth embodiment. [Modes for carrying out the invention]

[0009] 1. First Embodiment First, the motor 1 assembled according to the assembly method of the motor 1 according to the first embodiment will be described with reference to Figures 1 to 4. In addition, Figures 2, 3, and 4 show the motor 1 with the ring member 6 removed for the convenience of explaining the internal configuration.

[0010] Furthermore, for the sake of clarity, in Figures 1, 3, 4, 7, and 9, the top and bottom directions refer to the upper side of the paper as the up direction and the lower side as the down direction. In this embodiment, the up direction is the first direction and the down direction is the second direction.

[0011] As shown in FIGS. 1 to 4, the motor 1 according to this embodiment includes a rotor 2, a stator 3, a bearing 4, a case 5, and a ring member 6.

[0012] The rotor 2 includes a rotating shaft 11 and a magnet 12. The stator 3 includes a winding 13 and is disposed with a gap from the rotor 2. The bearing 4 holds the rotating shaft 11 at one end in the upward direction, which is the first direction in the axial direction of the rotating shaft 11. The ring member 6 is fixed to the ring member fixing portion 15 in a state where the bearing 4 is pressed downward in the second direction opposite to the first direction.

[0013] The case 5 includes a base case 51 that houses the rotor 2, the stator 3, and the bearing 4 and holds the rotor 2 downward, and a cover case 52 that covers a part of the rotor 2, the stator 3, and the bearing 4.

[0014] The case 5 has a bearing fixing portion 14 for fixing the bearing 4 at one end in the upward direction of the cover case 52, a ring member fixing portion 15 for fixing the ring member 6 and located upward in the first direction of the bearing fixing portion 14, and a plurality of notch portions 16 in which the ring member fixing portion 15 is notch-cut in the radial direction so that the diameter is larger than the inner diameter of the bearing fixing portion 14.

[0015] The bearing 4 is fixed to the bearing fixing portion 14 by an adhesive applied to the notch portion 16. The ring member 6 is fixed to the ring member fixing portion 15. The method of fixing the ring member 6 to the ring member fixing portion 15 is to cut threads on the surfaces of the ring member 6 and the ring member fixing portion 15 facing each other, press the bearing 4 downward in the second direction opposite to the first direction, and fix it by screwing. Incidentally, an adhesive may be applied to the surfaces of the ring member 6 and the ring member fixing portion 15 facing each other for fixing.

[0016] In Case 5, a connector 31 for externally applying current to the stator 3 is provided at one end of the side surface of the base case 51.

[0017] In the motor 1 of the present embodiment, a notch 16 is provided in the ring member fixing portion 15. Therefore, after inserting a dispenser into the notch 16 and applying an adhesive to the side surface of the bearing 4 within the notch 16, that is, after applying an adhesive material within the notch 16, the bearing 4 is inserted into the bearing fixing portion 14. Thus, the adhesive applied to the notch 16 is applied to the side surface of the bearing 4, and the adhesive area with the bearing fixing portion 14 can be widened. Therefore, a motor 1 with improved fixing force between the bearing 4 and the bearing fixing portion 14 can be obtained. Note that "applying an adhesive material to the notch 16" may mean applying an adhesive material into the notch with a dispenser or the like, or applying an adhesive to the side surface of the bearing 4 within the notch 16 with a dispenser or the like.

[0018] Next, the assembling method of the motor 1 according to the first embodiment will be described with reference to FIGS. 5, FIGS. 6, and FIGS. 7.

[0019] As shown in FIG. 5, the assembling method of the motor 1 includes a stator mounting step S1, a cover case mounting step S2, an adhesive application step S3, a bearing fixing step S4, and a ring member fixing step S5.

[0020] In the stator mounting step S1, the stator 3 is mounted on the cover case 52.

[0021] In the cover case mounting step S2, the base case 51 is mounted on the cover case 52, and the stator 3 is housed in the case 5.

[0022] In the adhesive application process S3, with the rotor 2, into which the bearing 4 is inserted, suspended above the case 5, adhesive is applied to the notch 16 using a dispenser. At this time, the adhesive may be applied directly to the notch 16 using a dispenser, or the adhesive may be applied to the side surface of the bearing 4 within the notch 16.

[0023] In bearing fixing step S4, the rotor 2 with the bearing 4 inserted is inserted into the case 5 and attached to the base case 51, and the bearing 4 is inserted into the bearing fixing part 14 and fixed to the bearing fixing part 14. When the bearing 4 is inserted into the bearing fixing part 14, the adhesive applied to the notch 16 adheres to the side surface of the bearing 4, and the bearing 4 can be fixed to the bearing fixing part 14 by this adhesive.

[0024] Furthermore, since the adhesive applied to the notch 16 adheres to the side surface of the bearing 4, the contact area with the bearing fixing part 14 is increased, thereby improving the fixing force between the bearing 4 and the bearing fixing part 14. By providing multiple notches 16, the adhesive can be applied uniformly to the side surface of the bearing 4, further improving the fixing force between the bearing 4 and the bearing fixing part 14.

[0025] In the ring member fixing step S5, as shown in Figures 6 and 7, the ring member 6 and the ring member fixing part 15 have threads on their opposing surfaces. The ring member 6 is fixed to the ring member fixing part 15 by pressing the bearing 4 downwards with the ring member 6 while screwing it in. By pressing the bearing 4 downwards while fixing it in place, the rotor 2 into which the bearing 4 is inserted can be attached to the case 5 more stably.

[0026] Through the above steps, the motor 1 shown in Figure 1 is assembled.

[0027] In this embodiment, the motor 1 is assembled by applying adhesive to the notch 16 provided in the ring member fixing part 15, and then inserting the bearing 4 into the bearing fixing part 14. As a result, the adhesive applied in the notch 16 adheres to the side surface of the bearing 4, increasing the contact area with the bearing fixing part 14. Therefore, the fixing force between the bearing 4 and the bearing fixing part 14 can be improved.

[0028] 2. Second Embodiment Next, the assembly method of the motor 1 according to the second embodiment will be described.

[0029] The assembly method of the motor 1 in this embodiment is the same as that of the motor 1 in the first embodiment, except that the adhesive used is a UV-curing adhesive, and in the adhesive application step S3, the adhesive is applied to the notch 16 after the bearing 4 is inserted into the bearing fixing part 14. The explanation will focus on the differences from the first embodiment described above, and similar matters will be omitted.

[0030] In the assembly method of the motor 1 of this embodiment, a UV-curing adhesive that hardens when exposed to UV light is used as the adhesive.

[0031] The assembly method for motor 1 involves, in adhesive application step S3, inserting the bearing 4 into the bearing fixing part 14, and then applying adhesive to the notch 16. Subsequently, in bearing fixing step S4, UV irradiation is applied to the adhesive applied to the notch 16 to cure the adhesive, thereby fixing the bearing 4 to the bearing fixing part 14.

[0032] In this embodiment, the assembly method for the motor 1 uses an adhesive that hardens with UV irradiation, resulting in a shorter curing time compared to thermosetting adhesives. Therefore, the bearing 4 and the bearing fixing part 14 can be fixed in a short time, thereby reducing the assembly time of the motor 1.

[0033] 3. Third Embodiment Next, the motor 1a assembled according to the assembly method of the motor 1a according to the third embodiment will be described with reference to Figures 8 and 9. Figure 9 illustrates the laser beam 24, which will be explained later in the assembly method of motor 1a.

[0034] The motor 1a of this embodiment is the same as the motor 1 of the first embodiment, except that it has an oil seal 21 and an oil seal holding member 22 for fixing the oil seal 21. The explanation will focus on the differences from the first embodiment described above, and similar matters will be omitted.

[0035] As shown in Figures 8 and 9, the motor 1a according to this embodiment includes a rotor 2, a stator 3, a bearing 4, a case 5, a ring member 6, and an oil seal retaining member 22.

[0036] The oil seal retaining member 22 secures the oil seal 21, which prevents oil from entering the case 5 from the outside. The oil seal retaining member 22 has a surface facing upward, which is the first direction, and is provided with a plurality of recesses 23 that are recessed downward, which is the second direction. The recesses 23 overlap with the case 5 when viewed from the axial direction of the rotating shaft 11. It is also desirable that the recesses 23 do not overlap with the notch 16 when viewed from the axial direction of the rotating shaft 11. The oil seal retaining member 22 is fixed to the case 5 by welding the oil seal retaining member 22 and the case 5 by irradiating the recess 23 with laser light 24.

[0037] In this embodiment, the motor 1a can fix the oil seal retaining member 22 that secures the oil seal 21 to the case 5 in a short time by irradiating a laser beam 24 into a plurality of recesses 23 provided on the upper surface of the oil seal retaining member 22 and welding it to the case 5, and also eliminate the need for fastening screws or the like.

[0038] Next, the assembly method of the motor 1a according to the third embodiment will be described with reference to Figures 9 and 10.

[0039] The assembly method for motor 1a in this embodiment is the same as that for motor 1 in the first embodiment, except that a step for fixing the oil seal retaining member has been added. The explanation will focus on the differences from the first embodiment described above, and similar matters will be omitted.

[0040] The assembly method for motor 1a, as shown in Figure 10, includes a stator mounting step S11, a cover case mounting step S12, an adhesive application step S13, a bearing fixing step S14, a ring member fixing step S15, and an oil seal retaining member fixing step S16.

[0041] The stator mounting process S11 to the ring member fixing process S15 are the same as the assembly method of the motor 1 in the first embodiment, so their explanation will be omitted.

[0042] In the oil seal retaining member fixing process S16, an oil seal 21 is placed above the ring member 6 to prevent oil from entering from outside the case 5, and is fixed with an oil seal retaining member 22. The method for fixing the oil seal retaining member 22 is to position the oil seal retaining member 22 such that a recess 23 that is recessed downwards (a second direction) on the surface of the oil seal retaining member 22 facing upwards (a first direction) overlaps with the case 5 when viewed from the axial direction, and as shown in Figure 9, the oil seal retaining member 22 and the case 5 are welded together by irradiating the recess 23 with laser light 24, thereby fixing the oil seal retaining member 22 to the case 5.

[0043] Through the above steps, the motor 1a shown in Figure 8 is assembled.

[0044] In this embodiment, the assembly method for the motor 1a involves welding the oil seal retaining member 22 and the case 5 by irradiating a recess 23 provided in the oil seal retaining member 22 with laser light 24, thereby fixing the oil seal retaining member 22 to the case 5. As a result, the oil seal 21, which prevents oil from entering from outside the case 5, can be fixed by the oil seal retaining member 22, and a motor 1a that prevents oil intrusion can be assembled. Furthermore, the surface of the oil seal retaining member 22 facing upward, which is the first direction, does not necessarily have to have a recess 23. For example, even if the surface of the oil seal retaining member 22 facing upward, which is the first direction, is flat, it is sufficient if the oil seal retaining member 22 and the case 5 can be welded by irradiating them with laser light 24.

[0045] 4. Fourth Embodiment A robot 100 having motors 1,1a according to the fourth embodiment will be described with reference to Figure 11.

[0046] Figure 11 illustrates an example using the motor 1 assembled according to the assembly method of the motor 1 according to the first embodiment. In Figure 11, the vertical direction coincides with the vertical direction, and the upper side of the paper is also referred to as "up" and the lower side as "down". For the robot arm 72, the first arm 73, and the second arm 74, the right side in Figure 11 is also referred to as the "base end" and the left side as the "tip end".

[0047] Furthermore, in this specification, "vertical" means not only when it coincides with the vertical, but also when it is slightly inclined from the vertical, for example, within ±10°. Furthermore, in this specification, "parallel" means not only when two objects coincide parallel to each other, but also when they are slightly inclined from parallel, for example, within ±10°.

[0048] The robot 100 of this embodiment is equipped with motors 1 assembled according to the assembly method of the motor 1 of the first embodiment at the first joint 10K and the second joint 20K. The motor 1 located at the first joint 10K and the motor 1 located at the second joint 20K have substantially the same configuration except for differences in torque and rotational speed.

[0049] In this embodiment, robot 100 is a SCARA robot and is used for various tasks such as holding, transporting, assembling, and inspecting workpieces such as electronic components. However, the application of robot 100 is not particularly limited. Furthermore, robot 100 may be other than a SCARA robot, such as a 6-axis articulated robot or a dual-arm robot.

[0050] As shown in Figure 11, the robot 100 includes a base 71, a robot arm 72 rotatably connected to the base 71, and a robot control device 9 that controls the driving of each part of the robot 100. The robot arm 72 also includes a first arm 73 whose base end is connected to the base 71 and which rotates around a first rotation axis J1 perpendicular to the base 71, and a second arm 74 whose base end is connected to the tip of the first arm 73 and which rotates around a second rotation axis J2 perpendicular to the first arm 73.

[0051] A working head 75 is provided at the tip of the second arm 74. The working head 75 has a spline nut 751 and a ball screw nut 752 arranged coaxially at the tip of the second arm 74, and a spline shaft 753 inserted through the spline nut 751 and the ball screw nut 752. The spline shaft 753 is rotatable about a third rotation axis J3 which is the central axis of the second arm 74 and runs vertically along it, and is also vertically movable along the third rotation axis J3.

[0052] An end effector 76 is attached to the lower end of the spline shaft 753. The end effector 76 is detachable from the spline shaft 753, and the appropriate one can be selected for the intended work.

[0053] The robot 100 has a first joint 10K that rotatably connects the base 71 and the first arm 73, and a motor 1 is installed in this first joint 10K to rotate the first arm 73 around a first rotation axis J1 relative to the base 71.

[0054] Furthermore, the robot 100 has a second joint 20K that rotatably connects the first arm 73 and the second arm 74, and a motor 1 is installed in this second joint 20K to rotate the second arm 74 around the second rotation axis J2 relative to the first arm 73.

[0055] Furthermore, the robot 100 includes a first drive mechanism 791 that rotates a spline nut 751 to rotate the spline shaft 753 around a third rotation axis J3, and a second drive mechanism 792 that rotates a ball screw nut 752 to raise and lower the spline shaft 753 in a direction along the third rotation axis J3. The second drive mechanism 792 is installed below the first drive mechanism 791.

[0056] The motor 1 located at the second joint 20K is positioned closer to the tip than the motor 1 located at the first joint 10K, and the spline nut 751, ball screw nut 752, spline shaft 753, first drive mechanism 791, and second drive mechanism 792 are all positioned closer to the tip than the motor 1 located at the second joint 20K.

[0057] The robot 100 of this embodiment is equipped with a motor 1 that has a strong fixing force between the bearing 4 and the bearing fixing part 14, thus achieving excellent reliability. [Explanation of symbols]

[0058] 1,1a...Motor, 2...Rotor, 3...Stator, 4...Bearing, 5...Case, 6...Ring member, 11...Rotating shaft, 12...Magnet, 13...Winding, 14...Bearing fixing part, 15...Ring member fixing part, 16...Notch, 21...Oil seal, 22...Oil seal retaining member, 23...Recess, 24...Laser beam, 31...Connector, 51...Base case, 52...Cover case, 100...Robot.

Claims

1. A rotor equipped with a rotating shaft, A stator is positioned with a gap between it and the rotor, A bearing that holds the rotating shaft at one end in the first axial direction of the rotating shaft, A case housing the rotor, the stator, and the bearing, A method for assembling a motor having a ring member that presses the bearing toward a second direction opposite to the first direction and is fixed to the case, The aforementioned case is, A bearing fixing part for fixing the aforementioned bearing, The ring member is fixed, and the ring member fixing portion located in the first direction of the bearing fixing portion, The ring member fixing portion has a plurality of radially cut-out portions such that its diameter is larger than the inner diameter of the bearing fixing portion, The steps include applying adhesive to the notched portion, The steps include inserting the bearing into the bearing fixing portion and fixing the bearing to the bearing fixing portion, The process includes fixing the ring member to the ring member fixing portion, How to assemble a motor.

2. The ring member and the ring member fixing portion are each threaded on the surfaces facing each other. A method for assembling a motor according to claim 1.

3. The adhesive is applied to the notched portion using a dispenser. A method for assembling a motor according to claim 1 or claim 2.

4. The application of the adhesive is performed by applying the adhesive to the notch while the bearing, including the rotor, is suspended above the case. A method for assembling a motor according to claim 3.

5. The aforementioned adhesive hardens upon UV irradiation, After inserting the bearing into the bearing fixing portion, the adhesive applied to the notch is irradiated with UV light to cure the adhesive, thereby fixing the bearing to the bearing fixing portion. A method for assembling a motor according to claim 1 or claim 2.

6. The ring member has an oil seal holding member in the first direction for fixing an oil seal that prevents oil from entering from outside the case, The surface of the oil seal retaining member facing the first direction is provided with a plurality of recesses that are recessed in the second direction, The recessed portion overlaps with the case when viewed from the axial direction, The oil seal retaining member is fixed to the case by irradiating the recess with laser light. A method for assembling a motor according to claim 1.

7. A rotor equipped with a rotating shaft, A stator is positioned with a gap between it and the rotor, A bearing that holds the rotating shaft at one end in the first axial direction of the rotating shaft, A case housing the rotor, the stator, and the bearing, A motor having a ring member that presses the bearing toward a second direction opposite to the first direction and is fixed to the case, The aforementioned case is, A bearing fixing part for fixing the aforementioned bearing, The ring member is fixed, and the ring member fixing portion located in the first direction of the bearing fixing portion, The ring member fixing portion has multiple notches, each notched radially such that its diameter is larger than the inner diameter of the bearing fixing portion. The bearing is fixed to the bearing fixing portion by the adhesive applied to the notched portion. The ring member is fixed to the ring member fixing portion. motor.

8. Having the motor described in claim 7, robot.

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