JP2556211Y2 - Drive shaft - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION [Industrial Application Field] The present invention relates to a drive shaft, particularly to a drive shaft capable of easily adjusting a rotational balance.

[Conventional technology]

Drive shafts that transmit rotational torque from a driving device to a driven device, such as a driving shaft (propeller shaft) of an automobile or a driving shaft for a rolling roll of a rolling mill, are partially cut, processed, heat-treated, and assembling parts. Often, the rotation balance gets out of order. When the drive shaft is rotated in a state in which the rotational balance is out of order, vibration is generated and unexpectedly large stress may be generated inside. For this reason, various methods for adjusting the rotational balance of the drive shaft have conventionally been devised. For example, a drive shaft in which a balance plate having a welding hole formed around the outer periphery is welded (Japanese Utility Model Application Laid-Open No. 56-139044), a drive shaft in which a chip-shaped balance weight whose weight is adjusted by cutting is screwed to the outer periphery, a rotating body itself There is known a drive shaft (Japanese Patent Laid-Open No. 59-110942) and the like having a resin layer which is annularly fixed to the peripheral surface of the rotating body and has a resin layer which is cut off according to the amount of unbalance when the balance of the rotating body is corrected.

[Problems to be solved by the invention]

In the case of conventional drive shafts that can adjust rotational balance, if further correction is required after balance adjustment, new balance weights must be welded or cut off. Must be removed from the drive shaft many times, and the drive shaft has problems such as the need to form an extra annular resin layer around the axis and repeat the cutting until the rotation balance is obtained. However, the adjustment of the rotation balance requires time and labor because of the repetition of cutting and adjustment. The present invention has been made to solve such a problem, and an object of the invention is to provide a drive shaft capable of easily, quickly and accurately adjusting the rotational balance of the drive shaft.

[Means for solving the problem]

That is, in order to solve the above problem, the present invention forms an annular groove having a wide bottom portion on the surface of the drive shaft, which is interposed between the drive device and the driven device and transmits the rotational torque. At the same time, in the annular groove, a balance weight formed of a metal piece having a circular cross section in the longitudinal direction and having a width slightly smaller than the width of the annular groove on the inlet side is freely movable in the circumferential direction. The balance weight is formed with a radial through hole at a predetermined position from both ends thereof, and a female screw for screwing a male screw from the upper surface to the inside of the through hole is formed at each lower end of the female screw. It is characterized by being formed by threading so that the portion and the tip of the male screw abut against each other, and opening a slit communicating with each through hole in the circumferential direction.

[Action]

When the drive shaft is the above means, the balance weight inserted in the annular groove can be moved in the circumferential direction to adjust the rotational balance. Then, when the rotational balance is obtained, the distal end of the male screw is abutted against the lower end of the female screw, and when the screw is further screwed in, the two legs on both sides of the slit are further opened due to a so-called wedge effect, whereby the two legs are formed into an annular shape. The balance weight can be tightened into these annular grooves by pressing against the side walls of the grooves. Thus, movement of the balance weight in the circumferential direction is restricted, and even if a centrifugal force is applied during rotation, the annular groove has a dovetail shape, so that it can reliably prevent the balance weight from projecting to the outside.

〔Example〕

Hereinafter, specific embodiments of the present invention will be described with reference to the drawings.

FIG. 7 is a side view including a partial axial sectional view of the drive shaft 1 for transmitting the rotational torque from the torque converter to the speed reducer, and FIG. 8 is a sectional view taken along line XX of FIG. The drive shaft 1
A drive-side fitting yoke 2 connected to a power source (not shown); a universal joint 3 for centering having one end connected to the fitting yoke 2; and a drive-side fitting connected to the universal joint 3. A shaft 4, a driven shaft 5 connected to the driving shaft 4 via a ball B so as to be integrally rotatable, and a centering universal joint 6 connected to the driven shaft 5. And a fitting yoke 7 on the reduction gear side connected to the other end of the universal joint 6. As shown in FIG.
A plurality of ridges 41, 51 facing each other and extending in the axial direction are formed on the driven side shaft 5, and a plurality of balls B are interposed in these ridges 41, 51, whereby the driving side shaft 4 The driven side shaft 5 is a kind of spline connection and is relatively movable in the axial direction.

In the drive shaft 1 having the above-described configuration, the drive-side shaft 4 and the driven-side shaft 5 are respectively formed with annular grooves 42 and 52 near the ends thereof along the outer periphery thereof. These annular grooves 42,
At least two balance weights 8 are inserted into the 52 so as to be movable in the circumferential direction.

FIG. 1 is a perspective view of the balance weight 8, and FIG. 2 is a sectional view of the balance weight 8 (also an enlarged view of a portion P in FIG. 7). The annular grooves 42, 52 are dovetail-shaped on the bottoms 42a, 52a side, and are formed gradually wider in the radial direction. The balance weight 8 is a metal piece having a circular cross section in the longitudinal direction, and the width D is formed to be slightly smaller than the width W on the inlet side of the annular grooves 42, 52. Then, radial through holes 84, 84 are formed at two predetermined positions E, E from the ends. Female screws 81, 81 are threaded into the through holes 84, 84 from the upper surface to the middle of the inside, and male screws 9, 9 such as holo set bolts are screwed into the female screws 81, 81. The distal ends 91, 91 of the male screws 9, 9 abut against the lower ends 81a, 81a of the female screws 81, 81, respectively. Further, slits 82, 82 communicating with the through holes 84, 84 from outside are formed in the balance weight 8 so as to open in both circumferential directions of the annular grooves 42, 52. Therefore, both sides of these slits 82, 82
It can be expanded to 3,83.

The balance weight has the shape as described above, and the distal ends of the external threads 9, 9 are abutted against the lower end 81a of the internal thread 81, and when the screw is further screwed in, as shown in FIG. The two legs 83, 83 on both sides of the slit 82 are further opened, so that the two legs 83, 83 are connected to the side walls 42 of the annular grooves 42, 52.
The balance weight 8 can be tightened into these annular grooves 42 and 52 by being pressed against the b and 52b. Accordingly, the movement of the balance weight 8 in the circumferential direction is restricted, and the balance weight 8 is also prevented from jumping out even when a centrifugal force is applied during rotation.
In particular, since the annular grooves 42 and 52 are dovetail-shaped, the protrusion of the balance weight 8 can be reliably prevented. next,
The method of adjusting the rotational balance of the drive shaft 1 according to the present invention will be described with reference to FIGS.

First, with the balance weight 8 removed from the annular grooves 42 and 52, a lightly balanced portion A on the circumference of the drive shaft 1 is marked by the balance measuring device. Next, the annular grooves 42,5
2. Insert two balance weights 8 into each of the two, place them on both sides of the mark, and
And temporarily fix each balance weight 8 at the corresponding position (see FIG. 3). Measure the balance in this state,
If the balance has not been achieved, the balance weights 8 are moved to the side with the heavier balance by the same angle α (FIG. 4). Thereafter, the above operation may be repeated until the balance is obtained. If the rotation balance cannot be obtained with only the two balance weights 8, the balance weight 8 may be additionally inserted into the mark A and the same adjustment as above may be repeated (see FIG. 6).

As described in detail above, in the drive shaft 1 of the present invention, the balance weight 8 is moved along the annular grooves 42 and 52,
The rotation balance can be adjusted simply by tightening or loosening 9,9. In this case, the adjustment of the rotational balance can be performed very easily and quickly because the lock and release of the lock of the balance weight 8 are only performed, and the rotational balance can be finely adjusted, so that the adjustment can be performed accurately.

In the drive shaft 1 of the present invention, the case where the annular grooves 42 and 52 are on the dovetail groove has been described. However, the shape of the groove can be applied to a T-shaped groove having a wide bottom. Further, the female screw 81 of the balance weight 8 and the male screw screwed thereto may be tapered screws. Further, the drive shaft of the present invention can be widely applied not only to a drive shaft such as a rolling roll of an automobile or a rolling mill, but also to a drive shaft interposed between a rotary drive device and a driven device to transmit rotary torque. Of course.

[Effect of the invention]

The drive shaft of the present invention has a configuration as described in detail above, and the rotation balance can be adjusted extremely easily and quickly only by moving the balance weight along the annular groove and locking it. Also, the operation of balance adjustment is only to tighten or loosen the male screw,
In addition, fine adjustment of the rotational balance is also possible, so that the adjustment is extremely accurate.

[Brief description of the drawings]

FIG. 1 is a perspective view of a balance weight used for the drive shaft of the present invention, and FIG. 2 is a sectional view of the balance weight (FIG. 6).
FIG. 3 is an explanatory view of tightening the male screw of the balance weight to open the double leg portions on both sides of the going slit portion to press against the side wall of the annular groove, and FIGS. 4 to 6. Is an explanatory view showing a method of adjusting the rotational balance, FIG. 7 is a side view including a partial axial sectional view of a drive shaft for transmitting rotational torque from a torque converter to a speed reducer, and FIG.
It is X sectional view taken on the arrow. DESCRIPTION OF SYMBOLS 1 ... Drive shaft, 4 ... Drive side, 5 ... Driven side shaft 42, 52 ... Annular groove 42b, 52b ... Annular groove side wall 8 ... Balance weight 81 ... Female screw, 82 ... Slit, 83 ... Double leg part 9 ... Male screw

Claims (1)

(57) [Scope of request for utility model registration] 1. A drive shaft interposed between a driving device and a driven device for transmitting a rotational torque, an annular groove having a wide bottom portion is formed on the surface of the drive shaft, and a longitudinal groove is formed in the annular groove. A balance weight, whose cross section is an arc-shaped metal piece and whose width is slightly smaller than the width of the annular groove on the inlet side, is movably inserted in the circumferential direction, and is inserted into the balance weight. Are formed with radial through holes at predetermined positions from both ends thereof, and a female screw for screwing a male screw into the through hole from the upper surface to the inside of the through hole has a lower end portion of the female screw and a tip portion of the male screw. A drive shaft, which is formed so as to be screwed so as to be abutted, and is formed by opening a slit communicating with each of the through holes in a circumferential direction.