JP2007239783A - Bearing supporting method and robot device using this method - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To eliminate the causes of variation of a load by the radial load of a rotating shaft in the cantilever state and noise by eccentricity or the like of the shaft; to improve a supporting method of a bearing causing increase of the cost by complication of processing and assembling processes; and to provide a robot device using the supporting method. <P>SOLUTION: In the bearing supporting method for rotatably supporting the rotating shaft having a fixed outer ring and receiving the radial load, the outer ring is attached to a flexible member such as hard rubber. <P>COPYRIGHT: (C)2007,JPO&INPIT

Description

  The present invention relates to a method for supporting a bearing and to a robot apparatus using this method.

Conventionally, as shown in FIG. 10 of Japanese Patent Application Laid-Open No. 2004-59286, it is well known to attach a belt pulley to an output shaft from a motor that receives a radial load. In this case, the motor was cantilevered and minute vibrations were generated due to fluctuations in the load applied to the shaft or eccentricity of the shaft.
In order to eliminate such a cantilever state, a bearing support method is also known in which a shaft end on the side opposite to the motor is rotatably supported by a radial bearing to which an outer ring is fixed.
Japanese Patent Laid-Open No. 2004-5928

In the case of minute vibrations in the former, the pulleys on the driven side or the rotating shaft, etc. are affected over a long period of use, and the bearing outer ring that supports them and the member that supports the outer ring wear, so-called rattling occurs, Caused noise.
In the latter case, the machining of the member that supports the bearing outer ring requires high accuracy, and it is troublesome not only for machining but also for assembling, resulting in a cost increase.

  As described above, the object of the present invention is to eliminate the cause of noise caused by the load variation due to the radial load of the conventional output shaft in the cantilever state or the eccentricity of the shaft, etc. An object of the present invention is to provide a robot apparatus that uses the support method while improving the support method of the bearing, which requires man-hours and further increases the cost.

  To achieve such a purpose, a soft member that keeps the cantilevered state of the rotating shaft that receives the radial load and keeps it within the flexible range, such as when a pulley for power transmission is attached to the output shaft of the motor. By supporting the bearing outer ring, it is possible to absorb vibrations, reduce noise due to wear, etc., and further reduce the cost without significantly increasing the processing accuracy of the member supporting the bearing outer ring. The present inventor has reached the conclusion of the present invention.

    In order to achieve the above-mentioned object, the present invention provides a bearing support method in which an outer ring is fixed and a rotating shaft that receives a radial load is rotatably supported, and the outer ring is attached to a flexible member. It was.

  Moreover, this flexible member becomes a suitable bearing support method by using either rubber or hard rubber.

  Moreover, it becomes a suitable bearing support method by attaching this flexible member to a member with little deformation such as metal.

  Further, in the robot apparatus that drives and operates the power transmission means such as the timing pulley and the timing belt by the motor, the above-described bearing support method is used, so that a suitable robot apparatus is obtained.

According to the present invention, since the bearing outer ring is supported by the soft member that keeps the bearing within the flexible range, there are no disadvantages that cause noise and cost increase.

  Next, an embodiment of the present invention will be described with reference to FIG. The belt drive unit 1 has a drive shaft 3 driven by a motor 2, and a timing pulley 4 and a timing belt 5 attached to the drive shaft 3 allow the motor 2 to be connected to a slider device for a shaft (not shown). The output is transmitted. A ring receiver 7 attached to the frame 6 is attached to the shaft end of the drive shaft 3 on the side opposite to the motor. The inner surface of the ring receiver 7 is rotatably supported via a rubber ring 8. The bearing 9 is fitted and the bearing 9 is securely fixed by the lock nut 10 attached to the end of the drive shaft 3.

The rotational accuracy of the drive shaft 3 is not so high. Further, tension is applied by the timing belt 5 and some vibration is generated. However, the outer ring of the bearing 9 is caused by the rubber ring 8 to shake the shaft core due to a load change or the like. It became possible to absorb.
In addition, the deformation of the rubber ring 8 absorbs minute eccentricity, so that high-level work is not required for accuracy during component processing and adjustment during assembly, leading to cost reduction.

  In the above explanation, the outer ring of the bearing is brought into contact with the rubber ring to absorb the shaft core run-out due to a load change, etc., but the rubber ring is not used and the bearing is allowed as shown in FIG. A ring receiver 11 of a flexible member such as hard rubber kept within the bending range is preferred. Other flexible members, such as plastics and polymers, are more convenient if they are more durable, whether natural or artificial.

  Next, an axis slider device for an orthogonal robot using the bearing support method of the present invention will be described with reference to FIG. Reference numeral 20 denotes a robot shaft slider device. A ball screw 21 is supported by thrust load thrust bearings 22a and 22b fitted to fixing members such as a frame (not shown) at both ends, and is moved in the axial direction. There is no rotation and it is designed to rotate at the same position. A timing pulley 24 is attached to one shaft end extension 23, and an outer ring fixed to the frame 25 so as not to be cantilevered is supported by a radial bearing 27 fitted to a ring receiver 26. Therefore, the output of the motor 29 is transmitted to the ball screw 21 by the timing pulley 24 and the timing belt 28.

  In the radial bearing 27, as described above, the outer ring of the radial bearing 27 can absorb the vibration of the shaft core due to a load change or the like by the rubber ring 30.

  A nut 31 is screwed onto the ball screw 21. When the ball screw 21 rotates forward and backward, the nut 31 moves in the left-right direction in the figure as indicated by an arrow A. By attaching, a slider device for a robot shaft can be obtained.

  Since it is configured as described above, it eliminates causes of load fluctuation due to radial load of the conventional cantilevered rotary shaft, noise due to shaft eccentricity, etc., and increases man-hours during processing and assembly, Also, the bearing support method, which has been a cause of cost increase, has been improved, and a robot shaft slider device using the support method has been obtained.

  In the above description, the slider device using the bearing support method of the present invention has been described as an axis slider device for an orthogonal robot. However, the present invention is not limited to this, and power transmission of a timing pulley, a timing belt, etc. is performed by a motor. Any robot can be used as long as it is operated by driving the means, and can be used for various system robots such as a joint robot.

It is explanatory drawing which shows the bearing support method to which this invention is applied. It is explanatory drawing of other embodiment which shows the bearing support method to which this invention is applied. It is explanatory drawing which shows the outline | summary of the slider apparatus for shafts of the robot using this bearing support method.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Belt drive part 2 Motor 3 Drive shaft 4, 24 Timing pulley 5, 28 Timing belt 6 Frame 7, 26 Ring receiver 8, 30 Rubber ring 9 Bearing 10 Lock nut 11 Hard member ring receiver 20 Axis robot axis slider device 21 Ball screw 22 Thrust bearing 23 Shaft extension 25 Frame 27 Radial bearing 29 Motor 31 Nut

Claims (4)

      A bearing support method in which an outer ring is fixed and a rotary shaft that receives a radial load is rotatably supported, and the outer ring is attached to a flexible member.   The bearing support method according to claim 1, wherein the flexible member is made of rubber or hard rubber.   The bearing support method according to claim 1, wherein the flexible member is attached to a member such as a metal. A robot apparatus that drives and operates power transmission means such as a timing pulley or a timing belt by a motor, wherein the bearing support method according to any one of claims 1 to 4 is used. Robot device to do.

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