JPH05587Y2 - - Google Patents

Description

[Detailed Description of the Invention] [Industrial Application Field] The present invention relates to a shaft rotation drive in which an output shaft supported by a roller bearing is rotationally driven by a motor.

[Industrial Application Field] Such a shaft rotation mechanism is described in the specification of Japanese Patent Application No. 1983-47159 filed by the present applicant. This mechanism is shown in FIG.

This mechanism uses an outer rotor type direct drive motor.

In FIG. 2, 1 is a fixed central shaft, 2 is a housing that is rotated around the central shaft 1, and 3 is a cross roller bearing that rotatably supports the housing 2 on the central shaft 1. As shown in FIG. 3, the cross roller bearing 3 has a cylindrical rolling ring 33 between an outer ring 31 and an inner ring 32.
They are arranged so that the rotation axes alternate by 90 degrees. The outer ring 31 is divided into two parts, 31 ₁ and 31 ₂ , to enable the bearing to be assembled.

Reference numerals 4 and 5 designate ring-shaped pressurization members that apply pressurization in the axial direction to the outer rings 31 ₁ and 31 ₂ to remove play in the bearing 3 . The pressurizing members 4 and 5 are connected to the housing 2
is attached to.

Reference numeral 6 denotes a motor that rotationally drives the housing 2 , a stator 61 is attached to the central shaft 1 , and a rotor 62 is attached to the housing 2 .

7 is an optical encoder for detecting the rotation of the housing 2, which includes a code plate 71 formed with a transparent slit and rotating integrally with the housing 2, a light emitting element 72 disposed opposite to each other with the code plate 71 in between, and a light receiving element 72. It consists of an element 73.

In this device, a motor 6 rotates the housing 2 at low speed with high torque.

[Problems to be solved by the invention] In such a device, the motor 6 occupies a considerable portion, and although the motor 6 and encoder 7 are non-contact type, the bearing 3 has a lot of play. Therefore, nearly 1 ton of pressurization is applied by the ring members 4 and 5. For this reason, there was a problem that the structure became larger.

The present invention was made to solve these problems, and aims to realize a shaft rotation mechanism that can rotate the shaft at high torque and low speed with a compact configuration.

[Means for Solving the Problems] The present invention rotates a shaft supported by a roller bearing with a motor, and pressurizes the roller bearing by a pressurizing means to remove looseness. In the rotating mechanism of the shaft, the rolling wheels of the roller bearing are directly rotationally driven, and the outer ring and the inner ring are relatively moved by the frictional force generated between the rolling wheels of the bearing, the outer ring, and the inner ring due to the pressurization of the pressurizing means. This is a shaft rotation mechanism characterized by comprising a wheel rotation motor that rotates the shaft.

[Example] The present invention will be explained below with reference to the drawings.

FIG. 1 is a block diagram of an embodiment of a shaft rotation mechanism according to the present invention. Components in FIG. 1 that are the same as those in FIGS. 2 and 3 are given the same reference numerals.

In the apparatus shown in FIG. 1, the output shaft 81 of the wheel rotation motor 8 is directly attached to the wheel 33 of the cross roller bearing 3, and the housing 2 is rotationally driven by this motor.

In this device, the outer ring of the cross roller bearing 3 is 3
It is divided into two parts, 1 ₁ and 31 ₂ , and looseness is removed by applying pressurization P ₁ and P ₂ to these outer rings using a ring member 4 . With this, the outer ring 31
A large frictional force acts between the inner ring 32 and the roller 33, and the housing 2 can be sufficiently driven by directly connecting the motor 8 to the roller 33.

Here, the diameter of the wheel 33 is d, and the diameter of the outer ring is D.
Then, since D/d is, for example, 10 to 20, this becomes the reduction ratio, and the wheel rotation motor 8 does not require a high torque motor.

Although power is transmitted from the rollers 33 to the outer and inner rings 31 and 32 by friction, if the rotation angle of the housing is directly measured using the encoder 7 (not shown in Fig. 1), slipping will not be a problem. There isn't.

The motors 8 are fixed to a retainer (not shown) of the rollers 33, and the number of motors 8 is sufficient to rotate the housing 2.

Moreover, as the bearing 3, a roller bearing other than a cross roller bearing, such as a cylindrical roller bearing, a circular roller bearing, etc. may be used.

[effect] According to the present invention, the following effects can be obtained.

Since a small motor can be used as the motor that rotates the bearing, the space occupied by the motor is reduced, and the mechanism can be made smaller.

The reduction ratio is the ratio of the bearing diameter to the rolling wheel diameter D/d
Therefore, an inexpensive high-speed, low-torque motor can be used to drive the shaft.

Various output torques can be freely selected depending on the number of motors used and the ratio D/d of the diameter of the roller and the diameter of the bearing.

[Brief explanation of drawings]

Figure 1 is a diagram showing the main parts of an embodiment of the shaft rotation mechanism according to the present invention, Figure 2 is a diagram showing an example of the configuration of a conventional shaft rotation mechanism, and Figure 3 is a diagram showing the configuration of a cross roller bearing. It is. 1...Central shaft, 2...Housing, 3...
... Cross roller bearing, 31, 31 ₁ , 31 ₂ ... Outer ring, 32 ... Inner ring, 33 ... Rolling wheel, 4, 5 ... Pressurization applying means, 8 ... Rolling wheel rotation motor.

Claims (1)

[Claims for Utility Model Registration] In a shaft rotation mechanism in which a shaft supported by a roller bearing is rotationally driven by a motor, and the roller bearing is pressurized by a pressurization applying means to remove looseness. , Directly driving the rolling wheels of the roller bearing to rotate, and relatively rotating the outer ring and the inner ring by the friction force generated between the rolling wheels of the bearing, the outer ring, and the inner ring due to the pressurization of the pressurization applying means, thereby rotating the shaft. A shaft rotation mechanism characterized by comprising a motor for rotating a rotating wheel.