WO2006030853A1

WO2006030853A1 - Cross groove type ball spline

Info

Publication number: WO2006030853A1
Application number: PCT/JP2005/017025
Authority: WO
Inventors: Akio Sakaguchi; Yoshihiko Hayama
Original assignee: Ntn Corporation
Priority date: 2004-09-15
Filing date: 2005-09-15
Publication date: 2006-03-23
Also published as: JP2006083937A

Abstract

A cross groove type ball spline adopted in the transmission system of a vehicle with variable gauge, comprising an inner ring (20) forming, in its outer peripheral surface, tracks (22) at angles relative to each other with respect to its axis, an outer ring (30) forming, in its inner peripheral surface, tracks (32) at angles relative to each other with respect to its axis, torque transmission balls (40) assembled in the cross parts of the tracks (22) of the inner ring (20) with the tracks (32) of the outer ring (30), and a cage (50) interposed between the outer peripheral surface of the inner ring (20) and the inner peripheral surface of the outer ring (30) and having pockets storing the torque transmission balls (40). The ball spline is coaxially disposed on the outer periphery of an axle (10), and the outer ring (30) is connected to the large gear of a gear box and the inner ring (20) is connected to a wheel.

Description

Specification

Cross Group Ball Spline Technology Field

[0001] The present invention relates to a cross group type ball spline, for example, a variable rail train for a railway vehicle (G CT: Gauge Changeable Train) capable of traveling on a plurality of types of tracks having different distances (gauges) between right and left rails. It can be used for a transmission system that connects the gearbox (reduction gear) and wheels in

Background art

[0002] Conventionally, as a transmission system that connects the gear box and wheels of a variable-gauge vehicle, inner teeth are provided in the outer cylinder, and outer teeth are provided in the inner cylinder, and large expansion and contraction in the axial direction is possible between the outer teeth and the inner teeth. Various sliding gears, ball splines or roller splines have been proposed.

[0003] FIG. 8 of Japanese Patent Laid-Open No. 10-278783 describes a sliding gear type power transmission spline. Referring to FIGS. 9A and 9B, a female sliding gear 3 extending in the axial direction is formed on the inner surface of the end portion of the drive cylinder 2. Further, a male sliding gear 5 having a short axial length that engages with the female sliding gear 3 is formed at the tip of the torque transmission cylinder 4 that rotates integrally with the wheel. Therefore, the wheel can be rotated via the torque transmission cylinder 4 by rotating the drive cylinder 2 by the drive motor. Further, the change in the gauge can be absorbed by the change in the meshing position between the female sliding gear 3 and the male sliding gear 5. Reference numeral 1 denotes an axle.

[0004] FIG. 1 of JP-A-10-278783 describes a ball spline type. Referring to FIGS. 10A and 10B showing a ball spline, a ball spline cylinder (5, 7) as a driving force transmitting means for transmitting a driving force to a wheel is provided coaxially with respect to the axle 1. The ball spline cylinder has an outer cylinder 5 and an inner cylinder 7 that are coaxial with each other, and an axial groove 6 formed on the inner peripheral surface of the outer cylinder 5 and an axial groove 8 formed on the outer peripheral surface of the inner cylinder 7. Ball 9 is interposed. The action of the ball 9 allows the outer cylinder 5 and the inner cylinder 7 to transmit driving force while sliding in the axial direction. As a result, the ball spline cylinder smoothly absorbs the change between the gauges while transmitting the driving force to the wheels and rotating the wheels. Can be collected.

Patent Document 1: Japan Fair Publication No. 07-047619 (Fig. 2)

Patent Document 2: JP-A-10-297487 (Figs. 1 and 8)

Disclosure of the invention

Problems to be solved by the invention

[0005] Rail cars are increasingly required to be quiet, just like automobiles. However, there is a problem of vibration noise caused by drive system backlash. The conventional transmission mechanism that connects the gear box of the variable-gauge truck and the wheel shaft has a clearance on the meshing surface, whether it is the above-described sliding gear type, ball spline or roller spline type. Due to this clearance, a so-called beating sound is generated due to speed fluctuations during rotation. In addition, due to slight misalignment of the connected axles, a sliding noise is generated in the sliding gear type as the meshing surfaces of the inner gear and outer gear slide. In the roller spline type, the force that allows the angle associated with misalignment to the clearance with the groove that stores the roller location. The same beating sound as the gear is generated between the roller and the groove that have almost no angle independence. .

[0006] A main object of the present invention is to reduce such a knocking sound and sliding sound, and to reduce the vibration sound of the entire vehicle.

Means for solving the problem

[0007] The present invention is a ball spline, that is, a cross group that applies a cross group joint that is capable of large expansion and contraction in the axial direction and has no backlash in the transmission system of the variable gauge carriage as a powerful vibration noise reduction measure. It is proposed to use a molded ball spline.

[0008] The cross group type ball spline of the present invention includes an inner ring in which a track forming an angle with respect to the axis is formed on the outer peripheral surface, an outer ring in which a track forming an angle with respect to the axis is formed on the inner peripheral surface, It consists of a torque transmission ball incorporated at the intersection of the track and the outer ring track, and a cage that is interposed between the outer peripheral surface of the inner ring and the inner peripheral surface of the outer ring and that has a pocket for accommodating the torque transmission ball.

[0009] When a cross group type ball spline is used in a transmission system for a variable-gauge carriage, it is arranged coaxially on the outer periphery of the axle, and for example, the outer ring is in contact with the large gear of the gear box. Next, connect the inner ring with the wheel.

[0010] Since the torque transmission ball is sandwiched between the inner ring track and the outer ring track, a large amount of expansion and contraction is possible due to the backlash in the rotational direction, and a slight error is caused by the rolling movement of the torque transmission ball. Alignment is also possible. Therefore, it contributes to further improvement of the quietness of railway vehicles.

[0011] At present, the variable amount of gauge required for mutual entry of the standard gauge and narrow gauge of railway vehicles is 368mm, and when applying one set each of the ball splines that can be expanded and contracted to the left and right wheels via a reducer, at least 184mm or more A large amount of expansion and contraction is required. Also, the friction coefficient between the railroad vehicle wheel and the rail is 0.35, the maximum torque applied to the ball spline at this time is 10KNm, the axle diameter is 180mm, and the inner ring must have at least an inner diameter larger than this. Nana! / Ball splines that can be expanded and contracted under such constrained conditions require high torsional rigidity and light weight in a limited space.

[0012] In order to secure the torque capacity by reducing the number of balls, the cross group type ball spline inevitably has an increased outer diameter and cannot satisfy a predetermined space. In addition, torque capacity cannot be secured even if balls are reduced in size (the ball diameter is the cube of the load capacity, and the number of balls directly affects the load capacity). If the crossing angle of the truck is less than 3 °, the moment acting on the cage cannot be balanced, and the angular freedom during misalignment is impaired (actually, only 2 ° or less is allowed). On the other hand, if the crossing angle of the track exceeds 7 °, it is not possible to secure adjacent tracks and a large amount of expansion and contraction cannot be secured. In this way, the cross group type ball spline of the present invention has a balance of torque transmission capacity, axle diameter, expansion / contraction amount and space, and has 10 to 18 torque transmission balls and a track crossing angle of 3 ° to 7 °. It is preferable to be in the range. For example, assuming a current railway vehicle, it is preferable that the number of balls is 14 or more and 18 or less, and the track crossing angle is 3 ° or more and 5 ° or less.

The invention's effect

[0013] By adopting a cross group type ball spline with no backlash as a transmission system that connects the gear box and wheel axle of the variable-gauge truck, the rattling noise found in conventional sliding gears and balls or roller splines. Vibration sound of the entire vehicle with no rubbing noise Can be reduced.

Brief Description of Drawings

FIG. 1 is a longitudinal sectional view of a cross group type ball spline showing an embodiment. FIG. 2 is a view taken along the line II-II in FIG.

FIG. 3 is a perspective view of a main part of a cross group type ball spline.

[Fig. 4] A developed view of the track.

FIG. 5 is a schematic diagram showing the track crossing angle.

FIG. 6 is a front view of the main part of a variable gauge carriage.

FIG. 7 is a front view of an essential part of a variable gauge truck showing another embodiment.

FIG. 8 is an enlarged cross-sectional view of a part VIII in FIG.

FIG. 9A is a longitudinal sectional view of a sliding gear showing a conventional technique.

FIG. 9B is a cross-sectional view of the sliding gear of FIG. 9A.

FIG. 10A is a longitudinal sectional view of a roller spline showing a conventional technique.

FIG. 10B is a cross-sectional view of the roller spline of FIG. 10A.

Explanation of symbols

[0015] 10 fast axis

12 wheels

14 Reducer

20 Inner ring

22 firewood rack

30 outer ring

32 卜 rack

40 Tonorek transmission

50 cage

52 Pogut

60 Seal fixing plate

68 O-ring

BEST MODE FOR CARRYING OUT THE INVENTION Hereinafter, embodiments of the present invention will be described with reference to the drawings.

Here, FIG. 1 shows a longitudinal section of the cross group type spline, and corresponds to an enlarged sectional view of a portion I in FIG. 6, which is a front view in which the bogie frame and the drive motor of the variable gauge carriage are omitted. In FIG. 6, an axle 10, a pair of wheels 12 supported on the axle 10, and a speed reducer 14 appear. The gauge-to-gauge variable carriage has a variable gauge as indicated by the white arrow. The standard gauge is indicated by a solid line, and the narrow gauge is indicated by a two-dot chain line. Fig. 2 is a view taken along the line II in Fig. 1, Fig. 3 is a perspective view of a main part of the cross-double spline shown in Fig. 1, Fig. 4 is a developed view of the truck, and Fig. 5 is a track crossing. It is a schematic diagram for explaining a corner.

As shown in FIG. 1, the cross group type ball spline includes an inner ring 20, an outer ring 30, a plurality of torque transmission balls 40 and a cage 50 as main components. The inner ring 20 is coaxially positioned on the outer periphery of the axle 10, and a plurality of tracks 22 are formed on the outer peripheral surface. The outer ring 30 is coaxially positioned on the outer periphery of the inner ring 20, and the same number of tracks 32 as the tracks 22 of the inner ring 20 are formed on the inner peripheral surface. As shown in FIG. 4, the track 22 of the inner ring 20 and the track 32 of the outer ring 30 are angled in opposite directions with respect to the axis. The angle formed by the axis and tracks 22 and 32 is called the track crossing angle α (see Fig. 5). A torque transmission ball 40 is incorporated at the intersection of the track 22 of the inner ring 20 and the track 32 of the outer ring 30. The cage 50 is interposed between the outer peripheral surface of the inner ring 20 and the inner peripheral surface of the outer ring 30 and has pockets 52 for accommodating the torque transmission balls 40 at equally spaced positions in the circumferential direction.

[0019] As a transmission mechanism that connects the gear box and wheels of the variable-gauge carriage, the pitch diameter of the torque transmission balls 40 is increased and the number thereof is increased, so that predetermined torque transmission and large expansion and contraction in the axial direction are possible. A cross group type ball spline can be used. Specifically, in consideration of the balance between the motor output, the load capacity, and the size of the main shaft 10, the number of torque transmission balls 40 is 10 or more and 18 or less, and the track crossing angle α of the inner and outer rings 20, 30 is A range of 3 ° to 7 ° is preferred. More specifically, for example, the number of torque transmission balls 40 is 14, and the crossing angle of the inner and outer rings 20, 30 is 3 °.

[0020] In consideration of assemblability, the inner ring 20 is a type that can be axially separated from the cage 50, that is, the maximum outer diameter of the inner ring 20 is made smaller than the minimum inner diameter of the cage 50.

A seal fixing plate 60 is attached to one end of the outer ring 30. Seal fixing plate 60 is cylindrical part 6 4 and the flange portion 62 formed at one end of the cylindrical portion 64 and the seal portion 66 formed at the other end of the cylindrical portion 64, and the flange portion 62 is fixed to the end face of the outer ring 30 with the bolt 70. is there. The cylindrical portion 64 is set to such a length that the track 22 of the inner ring 20 slid out from the outer ring 30 is not exposed beyond the O-ring 68 of the seal portion 66. The seal portion 66 has an O-ring 68 attached to an annular groove formed on the inner peripheral surface. The O-ring 68 is always in sliding contact with the outer peripheral surface of the inner ring 20 to prevent leakage of the lubricant filled inside and prevent foreign matter from entering from the outside.

As can be understood from FIG. 6, the outer ring 30 of the cross group type ball spline is connected to the large gear of the speed reducer 14, and the inner ring 20 is connected to the wheel 12. A torque of a driving motor (not shown) is transmitted to the outer ring 30 via the speed reducer 14 and further transmitted to the wheel 12 via the torque transmission ball 40 and the inner ring 20.

[0023] When changing the gauge distance, the inner ring 20 and the outer ring 30 are relatively displaced in the axial direction. FIG. 1 shows a state when the torque transmitting ball 40 is in a neutral position by a solid line, and shows a state at the time of slide-out and a slide-in by a two-dot chain line. In the figure, symbol C is the center of the torque transmitting ball 40 in the neutral position, C is the center of the torque transmitting ball 40 at the time of slide-in,

C indicates the center of the torque transmitting ball 40 during slide-out.

o

[0024] Since the torque transmission ball 40 is incorporated at the intersection of the tracks 22 and 32 and is sandwiched between the tracks 22 and 32, the torque transmission ball 40 has little or no play in the axial and circumferential directions. It is done. Therefore, the hitting noise as in the conventional sliding gear type or ball or roller spline type is eliminated or greatly reduced, and the vibration noise of the entire vehicle can be reduced.

[0025] The cross group type ball spline may be one per one wheel as in the embodiment of FIG. 1 described above, but as shown in FIG. 7 and FIG. If used, the amount of expansion / contraction per piece can be reduced, and the force can be increased at the crossing angle, further increasing the angular flexibility. In this case, the inner ring 20 may be integrated as shown, or separate inner rings may be connected using an intermediate shaft.

Claims

The scope of the claims

[1] Assembled at the intersection of the inner ring formed on the outer peripheral surface with a track forming an angle with respect to the axis, the outer ring formed with the track forming an angle with respect to the axis on the inner peripheral surface, and the track of the inner ring and the track of the outer ring A cross-groove ball spline composed of a recessed torque transmission ball and a cage that is interposed between the outer peripheral surface of the inner ring and the inner peripheral surface of the outer ring and that has a pocket for accommodating the torque transmission ball.

[2] The cross group type ball spline according to claim 1, wherein the track crossing angle is in the range of 3 ° to 7 °.

[3] The cross group type ball spline according to claim 1, wherein the number of torque transmitting balls is in the range of 10 to 18.

[4] Claims 1 and 3! A misaligned cross group type ball spline is coaxially arranged on the outer periphery of the axle, the outer ring is connected to the large gear of the gear box, and the inner ring is connected to the wheel. A transmission system that connects the gear box and wheels of a variable-gauge truck characterized by