JPH0247763Y2 - - Google Patents

Description

[Detailed Description of the Invention] (Industrial Application Field) This invention relates to a flexible shaft joint that allows large axial displacement.

(Prior Art) Transmission systems such as steel mills, coil winding devices, and refiners of paper manufacturing machines require flexible shaft joints that can tolerate large displacements (for example, 200 mm) in the axial direction. Conventionally, slide or telescopic gear couplings have been widely used as such flexible shaft couplings. This type of gear coupling spring has teeth cut into the inner surface of the outer cylinder with a tooth width slightly longer than the required stroke, or axial displacement, and the teeth on the inner cylinder mesh with these teeth.

(Problems to be solved by the invention) The slide or telescopic gear coupling described above absorbs all axial misalignment, eccentricity, and obliqueness by changing the contact position of the teeth. Pressure is high. Therefore, there is a problem that the teeth tend to be biased and wear out significantly, and the relative displacement of the inner cylinder and the outer cylinder in the axial direction is not smooth. In addition, it is noisy during operation, and it is necessary to frequently supply lubricating oil to prevent tooth surface wear. Furthermore, if a shock is applied to the transmission system, it does not have a function to cushion it. Therefore, a separate shock absorber must be provided in a transmission system that transmits torque that fluctuates widely and irregularly.

(Means for Solving the Problems) The flexible joint of this invention mainly consists of an outer cylinder, an inner cylinder, a hub, a spring seat, and a spring.

The outer cylinder has a flange at one end to which the transmission shaft is connected, and has a guide extending in the axial direction of the cylinder on its inner circumferential surface. The inner cylinder is provided with a plurality of long grooves and a plurality of guide grooves at regular intervals in the circumferential direction. The cross-sectional shape of the guide groove is a semicircle with a radius of curvature larger than the radius of curvature of the guide. The inner cylinder is inserted into the outer cylinder so as to be slidable in the axial direction of the cylinder, with a guide fitted in the guide groove. The hub has a flange with a plurality of long holes provided in a portion corresponding to the long groove, and the transmission shaft is connected to the hub. The spring seats have a semi-cylindrical surface and are combined to face each other to form a pair, with a spring interposed between them. The inner cylinder houses the flange of the hub therein with an appropriate gap to adjust the misalignment of the axis. Further, the center portion of the semi-cylindrical surface of the spring seat is supported by the long hole circular arc surface of the flange of the hub, and both end portions are supported by the long groove circular arc surfaces of the inner cylinder.

(Operation) In the flexible shaft joint configured as described above, torque is transmitted from the outer cylinder to the hub, or vice versa, via the inner cylinder, spring seat, and spring.
The cross-sectional shape of the guide groove is a semicircle with a radius of curvature larger than the radius of curvature of the guide. Therefore, since the contact portion between the guide surface and the guide groove surface moves along the semi-cylindrical surface, the relative displacement in the axial direction of the outer cylinder and the inner cylinder and the transmission of torque are performed smoothly. In addition, during torque transmission, the spring seat rolls against the long groove circular arc surface of the inner cylinder and the long hole circular arc surface of the hub flange, and is also allowed by the clearance between the inner cylinder, hub, spring seat, etc. These members undergo relative displacement within the range. These movements compensate for eccentricity and obliqueness of the transmission shaft. Further, the inner cylinder slides within the outer cylinder while being guided by the guide, and displacement in the axial direction is absorbed. The shock in the transmission system is alleviated by the elastic deformation of the spring.

(Example) FIGS. 1 and 2 show an example of this invention.

As shown in these drawings, mainly the outer cylinder 1, the inner cylinder 11, the hub 21, the spring seat 31, and the spring 41.
It is composed of.

The outer cylinder 1 has a flange 3 attached to one end of a main body 2, and an annular cover 6 attached to the other end with bolts 7. A power transmission shaft (none of which is shown) is connected to the cylindrical portion 4 of the flange 3 via a key. Guides 8 extending over the entire length are provided on the inner surface of the main body 2 at intervals of 60 degrees in the circumferential direction. The guide 8 has a semicircular cross-section,
It is fixed to the main body 2 with screws 9.

The inner cylinder 11 has two annular plates 1 each having a recess 13.
2 are butted together and tightened with bolts 14. Recess 1 of abutted annular plate 12
3 forms a space in which the hub flange 24 is accommodated. Each annular plate 12 is provided with six long grooves 16 at intervals of 60 degrees in the circumferential direction, and both sides of the long grooves 16 are arcuate surfaces 17, as shown in FIG. In addition, the inner cylinder 11 has a semicircular guide groove 19 cut in its outer peripheral surface to fit into the guide 8, and the main body of the outer cylinder 1 is slidable in the cylinder axis direction while being guided by the guide 8. It is inserted in 2. The cross-sectional shape of the guide groove 19 is a semicircle with a radius of curvature larger than that of the guide 8.

The hub 21 has a flange 24 provided at the tip of a cylindrical portion 22. The flange 24 is provided with six elongated holes 26 at intervals of 60 degrees in the circumferential direction, and as shown in FIG.
It is becoming. The elongated hole 26 corresponds to the elongated groove 16. A power transmission shaft (none of which is shown) is connected to the cylindrical portion 22 by a key.

The spring seat 31 is connected to the long groove 1 as shown in FIG.
6 and a semi-cylindrical surface 33 that comes into contact with the arcuate surfaces 17, 27 of the elongated hole 26, and the surface following the semi-cylindrical surface 33 is a flat surface 35. A coil spring 4 is placed on the plane 35.
1 is provided with a cylindrical projection 37 into which it fits. The radius of curvature of the semi-cylindrical surface 33 of the spring seat 31 is slightly smaller than that of the arc surfaces 17, 27 so that the spring seat 31 can easily roll on the arc surfaces 17, 27.

The cylindrical portion 22 of the hub 21 is the cover 6 of the outer cylinder 1.
The flange 24 of the hub 21 passes through the annular plate 12 on one side of the inner cylinder 11, and the flange 24 of the hub 21 passes through the annular plate 12 on one side of the inner cylinder 11, leaving an appropriate gap g between the hub 21 and the inner cylinder 11 to adjust the misalignment of the axis. It is stored inside.

The spring seats 31, which are combined so that the flat surfaces 35 face each other to form a pair, are connected to the elongated hole 2 of the hub flange 24.
6, and both ends thereof enter the long grooves 16 of the inner cylinder 11. And the facing spring seat 31
A coil spring 41 is interposed between them. Therefore, the center portion of the semi-cylindrical surface 33 of the spring seat 31 is supported by the long hole circular arc surface 27 of the hub flange 24, and both ends are supported by the long groove circular arc surface 17 of the inner cylinder 11. .

In the flexible shaft joint configured as described above, the torque is sequentially applied to the outer cylinder 1, guide 8, inner cylinder 11,
It is transmitted to the hub 21 via the spring seat 31, the coil spring 41, and the other spring seat 31. When the direction of the torque is reversed, the torque is transmitted in the reverse order.

The coil spring 41 is compressed depending on the magnitude of the torque. Then, the torque is transmitted as a spring force from the outer cylinder 1 to the hub 21 and vice versa via the other spring seat 31. At this time, the coil spring 41
Due to the compression, the inner cylinder 11 and the hub 21 are displaced relative to each other in the circumferential direction. However, the spring catch 3
Torque is transmitted without excessive force being applied to the coil spring 41 due to the rolling of the coil spring 41.

When the left and right transmission shafts are eccentric or oblique, the hub 21 is displaced relative to the inner cylinder 11 within the range allowed by the gap g to absorb the eccentricity or oblique. At the time of this displacement, the semi-cylindrical surface 33 of the spring seat 31 is connected to the long groove circular arc surface 17 of the inner cylinder 11 and the hub flange 2.
Since it rolls on the circular arc surface 27 of the long hole 4, force is applied to the coil spring 41 without being biased, and torque is transmitted smoothly. In addition, the shock in the transmission system is handled by the coil spring 41.
is relaxed by the elastic deformation of

(Effects of the invention) The flexible shaft joint of this invention absorbs eccentricity and skew between the inner cylinder and the hub, and axial deviation is absorbed by the relative displacement between the outer cylinder and the inner cylinder. . Further, the contact portion between the guide and the guide groove moves along the semi-cylindrical surface. Therefore, the guide and the guide groove do not wear unevenly, and the relative displacement in the axial direction of the outer cylinder and the inner cylinder and the transmission of torque are performed smoothly. Additionally, it is quiet during operation, reduces wear on guides, guide grooves, etc., and does not require frequent supply of lubricating oil. Furthermore, the elastic deformation of the coil spring alleviates the impact, thereby preventing damage to the transmission system due to the impact.

[Brief explanation of drawings]

1 and 2 show an embodiment of this invention, respectively, a side sectional view and a front sectional view of a flexible shaft joint, FIG. 3 is a partially enlarged view of the above-mentioned flexible shaft joint, and FIG. The figure is a perspective view of the spring seat. 1...Outer cylinder, 3...Flange, 8...Guide,
11... Inner cylinder, 16... Long groove, 17... Long groove circular arc surface, 21... Hub, 24... Hub flange, 26
...Elongated hole, 27...Elongated hole arc surface, 31...Spring catch, 33...Semi-cylindrical surface, 41...Coil spring.

Claims (1)

[Scope of utility model registration request] A flange 3 to which a transmission shaft is connected is provided at one end,
A plurality of guides 8 extending in the cylinder axis direction and having a semicircular cross-sectional shape are provided on the inner circumferential surface at regular intervals in the circumferential direction; A long groove 16 and a plurality of guide grooves 19 each having a semicircular cross-sectional shape with a radius of curvature larger than that of the guide 8 are provided. an inner cylinder 11 slidably inserted into the outer cylinder 1; a hub 21 having a flange 24 with a plurality of long holes 26 in a portion corresponding to the long groove 16; and a hub 21 to which a transmission shaft is connected; Consisting of a spring seat 31 having a semi-cylindrical surface 33 and a spring 41 interposed between the spring seats 31 that are combined to face each other to form a pair, the spring seat 31 has a gap g suitable for adjusting the misalignment of the axis.
The inner cylinder 11 accommodates the flange 24 of the hub 21 inside, and the center part of the semi-cylindrical surface 33 of the spring receiving seat 31 is connected to both ends by the elongated circular arc surface 27 of the flange 24 of the hub 21. are respectively supported by the long groove circular arc surfaces 17 of the inner cylinder 11.