JPH02212651A - Speed change gear - Google Patents

Abstract

PURPOSE:To enable the reduction of local friction of a rolling body and the like through enlargement of a speed change range by a method wherein rotation of an input shaft is transmitted to the rolling body, and the rolling body is revolved as it is rotated in a state to make contact with first and second guide surfaces and a guide groove. CONSTITUTION:When, by a transmission gear, a cylinder member 5 is moved laterally, a round part 6a of a rolling body 6 engaged with a guide groove 26 is moved laterally in a state to be engaged with the groove 26, and inclination of the rolling body 6 is changed. However, since a size relation is established among first and second guide surfaces 14 and 17, the groove 26, the round part 6a of the rolling body 6, and a spherical part 6b, even when inclination is changed, a contact state therebetween can be held. Since through rotation of an input shaft 2, a force, by which an input member 10 is forced to approach the rolling body 6, is exerted on the input member, contact of the rolling body 6 with the guide surfaces 14 and 17 and the groove 26 is further ensured. Rotation of the input member 10 occasioned by rotation of the input shaft 2 is transmitted to the rolling body 6, the rolling body 6 is revolved as it is rotated in a state that the rolling body is brought into contact with the guide surfaces 14 and 17 and the groove 26. A current differential action causes the change of the speed of rotation of the input shaft 2 to transmit it to an output shaft 3.

Description

DETAILED DESCRIPTION OF THE INVENTION Field of Industrial Application This invention relates to a transmission that is used as an automatic transmission that automatically changes the gear ratio depending on the load or a continuously variable transmission that changes the gear ratio steplessly. Regarding.

Background Art and Problems of the Invention As a transmission used as an automatic transmission or a continuously variable transmission, a plurality of spherical or conical rolling elements that rotate and revolve are interposed between an input shaft and an output shaft. One using a friction planetary mechanism is known.

However, such conventional transmission devices have the following problems.

In other words, the structure is 2. The shifting range is relatively small.

In addition, a spring such as a disc spring is required to maintain the sliding state of the rolling elements, and since the sliding contact point with the rolling elements is always constant, local wear occurs and the service life is short.

An object of the present invention is to provide a transmission that solves all of the above problems.

Means for Solving the Problems A transmission device according to the present invention includes an input shaft, an output shaft disposed coaxially with the input shaft, and a retainer coaxially and rotatably disposed around the input shaft and the output shaft. , is equipped with a cylindrical member disposed coaxially and axially movably around the cage, and a plurality of rolling elements held by the cage so as to rotate about their own axis and hang. A first guide surface perpendicular to the axis of the input shaft is provided on the input shaft or a part that rotates together with the input shaft, and a second guide surface tapered at 45 degrees is provided on the output shaft or a part that rotates together with the input shaft. An annular guide groove having an arcuate cross-sectional shape is provided on the inner peripheral surface of the cylindrical member, the rolling element has a substantially cylindrical shape, and a rounded part is provided around the entire outer periphery of one end of the rolling element. , a spherical part having a center on the axis of the rolling element is provided on the other end surface, two symmetrical places of the rounded part of the rolling element contact the first guide surface and the bottom of the guide groove, and the spherical part of the rolling element contacts the first guide surface and the bottom of the guide groove. 2 guide surfaces.

Operation Since the rounded portion of the rolling element fits into the guide groove of the cylindrical member, the inclination of the rolling element changes as the cylindrical member moves in the axial direction. By appropriately determining the radius of the spherical portion of the rolling element, even if the inclination of the rolling element changes, the state of contact between the rolling element and the first guide surface, second guide surface, and guide groove is always maintained. You can do it like this. Therefore, there is no need for a disc spring or the like to maintain the sliding state of the rolling elements, and there is no need to consider deterioration of the spring. Furthermore, when the inclination of the rolling elements changes, the contact points of the rolling elements and the contact points with the rolling elements change, thereby reducing local wear.

The rotation of the input shaft is transmitted to the rolling elements, and the rolling elements rotate while contacting the first guide surface, the second guide surface, and the guide groove, and the rotation of the input shaft is controlled by the differential action at this time. The speed is changed and transmitted to the output shaft. By changing the inclination of the rolling elements, the gear ratio changes, and since the inclination of the rolling elements can be changed greatly, the speed change range becomes very large.

Embodiment Hereinafter, one embodiment of the present invention will be described with reference to the drawings.

The drawing shows an example of an automatic transmission that automatically changes the gear ratio depending on the load. In addition, in the following explanation, upper, lower, left, and right refer to FIG. 1.

In FIGS. 1 and 2, the transmission includes a case (1
), an input shaft (2), an output shaft (3), a cage (4), a cylindrical member (5), and a plurality of rolling elements (6), for example, five.

The case (1) has a cylindrical shape and is arranged so that the axis (C) is a horizontal line in the left-right direction. An end wall (1a) having a circular hole (7) in the center is provided at the left end of the case (]). The right end of the case ( ) is open, and a cylindrical bearing housing (8) is coaxially fixed inside this part.

A flange portion (8a) is formed in a negative shape at the right end of the housing (8), and this portion is fitted inside the right end portion of the case (1). The input shaft (2) and output shaft (3) are
They are arranged coaxially on the axis (C) of the case (1) so that the input shaft (2) is on the left and the output shaft (3) is on the right.

A hole (9) is formed on the axis (C) of the human power shaft (2), reaching the middle part of the length from the left end surface. A flange part (2a) is coaxially formed at the middle part of the length of the input shaft (2), an input member support shaft part (2b) is on the right side of the flange part (2a), and a connecting shaft with a smaller outer diameter is further on the right side of the flange part (2a). The portion (2c) is formed coaxially.

A perforated disk-shaped input member (10) is rotatably fitted on the outside of the support shaft portion (2b) of the input shaft (2). A plurality of sets of four conical portions (11, 12) are formed on opposing surfaces of the flange portion (2a) of the input shaft (2) and the input member (10) so as to face each other at equal intervals in the circumferential direction. A steel ball (13) is fitted between the four opposing parts (11,) (12). Then, the right end surface of the input member (10) is
The first guide surface (1) perpendicular to the axis (C) of the human power shaft (2)
4). The rotation of the input shaft (2) is controlled by the recess (+,
1. ) (1, 2) via the steel ball (13) between the input member (
10). At this time, the steel ball (13) is placed in the recess (
11,) (12), so the input shaft (2
), the input member (10) is rotated by the flange part (2a).
Force is applied in the direction away from the object, that is, in the right direction.

A first hole (15) reaching the middle part of the length from the left end surface and a second hole (16) reaching the middle part of the length from the right end surface are formed on the axis (C) of the output shaft (3). ing.

A large-diameter portion (3a) having a larger outer diameter than other portions is coaxially formed at the left end of the output shaft (3), and a 45-degree tapered groove is formed at the left end of the outer periphery of the large-diameter portion (3a). 2 guide surfaces (1
7) is formed.

The connecting shaft part (2c) of the input shaft (2) is rotatably fitted into the first hole (15) of the output shaft (3), and the input shaft (2) and output shaft connected in this way Bearings (18), (19), and (2) rotate independently of each other.
0) is supported by the case (1) and the housing (8). In other words, the flange portion of the input shaft (2) (
A first thrust ball bearing (I8) is connected between the left side part of the output shaft (2a) and the inner peripheral part of the left end wall (1a) of the case (1), and the first thrust ball bearing (I8) is connected to the right side of the large diameter part (3a) of the output shaft (3) parts and housing (8
), and a radial ball bearing (20) between the right end portion of the output shaft (3) and the right end portion of the housing (8). It is provided.

The input shaft (2) projects slightly from the left end wall (la) of the case (1), and a seal (21) is provided between them. The output shaft (3) protrudes a little from the right end of the housing (8), and a seal (22) is also provided between them.

The retainer (4) has a cylindrical shape with steps on the inner and outer surfaces, as shown in the cross-sectional shape at the bottom of FIG. The inner surface of the output shaft (3) is rotatably received by the outer surface of the large diameter section (3a) of the output shaft (3). Five pockets (23) for supporting the rolling elements (6) are formed in the cage (4) at equal intervals in the circumferential direction.

The cylindrical member (5) is a case (1) surrounding the cage (4).
is arranged on the inner surface for rotational and axial movement. As shown in FIG. 3, the cylindrical member (5) has an elongated hole (24
) is formed. A pin (25) is fixedly provided on the inner surface of the case (1) to fit into the elongated hole (24) and restrict the movement of the cylindrical member (5). Also, Chodai (
24) A shallow guide groove (26) having an arcuate cross section is formed in an annular shape on the inner surface of the cylindrical member (5) on the right side.

As shown in detail in FIG. 4, the rolling element (6) has a short cylindrical shape, has a rounded part (8a) with a radius of a around the entire outer periphery of one end, and has a rounded part (8a) on the other end surface along the axis (A). A spherical portion (6b) having a radius centered at is provided. The rolling element (6) is
The axis line ( A) is housed in the pocket 1-(23) of the holder (4) in a tilted state. The outer surface of the middle cylindrical portion of the rolling element (6) is received by the walls on both sides of the pocket (23) in the circumferential direction, so that the rolling element (8) rotates about its axis (A). do. Further, the rolling elements (6) revolve around the input shaft (2) and the output shaft (3) as the cage (4) rotates. In the cross-sectional view of FIG. 4, the first guide surface (
14) Intersection of a vertical line (LL) located to the right of the radius a of the rounded part (6a) and a horizontal line (L2) located below the bottom of the guide groove (2G) by the radius a of the rounded part (6a) (0), then from this intersection (0) to the second guide surface (1
7) is the radius of the spherical portion (6b).

A compression coil spring (27) that biases the cylindrical member (5) leftward is provided between the flange portion (8a) around the housing (8) and the right end surface of the cylindrical member (5).

In the above transmission, when the cylindrical member (5) moves left and right, the rolling elements (6) fitted in the guide grooves (26)
) The rounded portion (6a) of the guide groove (26) moves from side to side while remaining in the guide groove (26), thereby changing the inclination of the transfer body (6) (the inclination of the axis (A)). However, the first guide surface (1
4) Since there is the above-mentioned dimensional relationship between the second guide surface (17), the guide center (26), the rounded part (6a) and the spherical part (6b) of the rolling element (6), FIG. As shown in , even if the inclination of the rolling element (6) changes, the rolling element (6) always
and guide surface (14) (17) and guide groove (26)
contact is maintained. Further, as described above, the input member (10) is rotated by the rotation of the input shaft (2) to the rolling element (6).
As the rolling element (6), the guide surface (14,) (1,7) and the guide groove (26) receive a force in the right direction approaching the
contact becomes more reliable. For this reason, there is no need to use a disc spring or the like to bring the rolling elements (6) into contact, and there is no need to consider deterioration of the spring. The rotation of the input member (10) due to the rotation of the input shaft (2) is transmitted to the rolling elements (6), and the rolling elements (6) move toward the guide surfaces (14) (1, 7).
The input shaft (2) rotates and revolves in contact with the guide groove (26), and the rotation of the input shaft (2) is changed in speed by the differential operation at this time and transmitted to the output shaft (3).

In Fig. 5, the rolling element (6) and the first guide surface 14)
The distance from the contact point (first contact point) (PL) to the axis (C) is R1, the distance from the first contact point (Pl) to the axis (A) is rl, and the distance between the rolling element (6) and the second Guide surface (17)
The distance from the contact point (second contact point> (R2) to the axis (C) is R2, the distance from the second contact point (R2) to the axis (A) is R2, and the distance between the rolling element (6) and the guide mist is The distance from the contact point (third contact point) (R3) to the axis (C) is R3, and the distance from the third contact point (R3) to the axis (A) is R3. When the inclination of the rolling element (6) changes, R
3 is constant, R1, R2, rl, R2 and R3
changes, thereby changing the gear ratio (the ratio of the rotational speed of the output shaft (3) to the rotational speed of the input shaft (2)). Regarding the second contact point (R2), when the inclination of the rolling element (6) is small, as shown in FIGS. 5(a) and (b), the axis (
A), but when the inclination of the rolling element (6) is large, the first contact point (Pl) is on the same side as the first contact point (Pl), as shown in FIGS. ), and in particular, the inclination of the rolling element (6) changes greatly in this way, and the contact point (R2) changes greatly, making it possible to change the gear ratio over a wide range. . In addition, rolling elements (6
) changes, the first contact point (Pl) on the first guide surface (14) and the second contact point (R) on the second guide surface (17) change.
2) The first contact point (Pl), second contact point (R2) and third contact point (R3) on the rolling element (6) also change, thus reducing the occurrence of local wear.

In the above transmission, when the load on the output shaft (3) changes, the torque acting on the cylindrical member (5) changes, so the action of the pin (25) and the long hole (24) causes the cylindrical member (5) to change.
The position of the rolling element (6) in the direction of the axis (C) changes, thereby automatically changing the inclination of the rolling element (6) as described above. In other words, when no load is acting on the output shaft (3), the fifth
As shown in Figure (a), the cylindrical member (5) is a spring (27).
The rolling element (6) is moved to the left end position, and the inclination of the rolling element (6) is small. When a load is applied to the output shaft (3), the cylindrical part (5) moves to the right against the spring (27), and the inclination of the rolling element (6) increases. Cylindrical member (5) at this time
The amount of movement corresponds to the size of the load, and as the load increases,
The inclination of the rolling element (6) increases in the order of d).

As shown in Figure 5(a), when no load is acting on the output shaft, the gear ratio is greater than 1, and the output shaft (3) is connected to the human power shaft (2) in the same direction as the input shaft (2). Rotate at a greater speed. That is, the rotation of the input shaft (2) is accelerated in the same direction and transmitted to the output shaft (3). For example, the gear ratio at this time is approximately 1°12.

When the load increases from a no-load state, the gear ratio gradually decreases, and when the state shown in Fig. 5(b) is reached, the gear ratio becomes 1, and the rotation of the input shaft (2) is directly transferred to the output shaft (3). As a result, the output shaft (3) rotates in the same direction and at the same speed as the input shaft (2).

When the load becomes even larger, the gear ratio becomes smaller than 1, and the output shaft (3) rotates in the same direction as the input shaft (2).
Rotate at a smaller speed. That is, the rotation of the input shaft (2) is decelerated in the same direction and transmitted to the output shaft (3).

For example, in the state shown in FIG. 4, the gear ratio becomes approximately 0.61, and as the load increases further, the gear ratio becomes even smaller.

When the state shown in FIG. 5(C) is reached, the gear ratio becomes 0, the rotational speed of the output shaft (3) becomes 0, and the output shaft (3) stops.

When the state shown in Fig. 5 (rl) is reached, the gear ratio becomes a negative value, and the output shaft (3) is connected to the input shaft (2) in the opposite direction to the input shaft (2).
Rotate at a smaller speed. In other words, the rotation of the input shaft (2) is transmitted to the output shaft (3) through deceleration 12 in the opposite direction.

For example, the gear ratio at this time is about -0.1.

In this way, in the above-mentioned transmission, the gear ratio changes automatically according to the load on the output shaft (3), and the gear ratio can be varied over a very wide range, for example from about -0.1 to about 1°12. Change range.

Although the automatic transmission device is shown in the above embodiment, the cylindrical part (5
) is moved in the axial direction by appropriate means and fixed at a predetermined position, resulting in a continuously variable transmission in which the gear ratio can be changed steplessly from the outside.

Effects of the Invention According to the transmission device of the present invention, as described above, the speed change range can be made very wide, and local wear of the rolling elements can be reduced.

Further, there is no need for a disc spring or the like to maintain the sliding state of the rolling elements, and there is no need to consider deterioration of the spring.

[Brief explanation of the drawing]

FIG. 1 is a longitudinal cross-sectional view of an automatic transmission showing one embodiment of the present invention, FIG. 2 is a cross-sectional view taken along the line ■-■ in FIG. 1, and FIG.
4 is an enlarged sectional view of the rolling element portion of FIG. 1, and FIG. 5 is a sectional view of the rolling element portion showing four different speed change states. (2)...Input shaft, (3)...Output shaft, (4)...
・Cage, (5)... Cylindrical member, (6)... Rolling element, (6a)... Rounded part, (6b)... Spherical part, (1
0)...Input member, (14)...First guide surface, (
17)...Second guide surface, (26)...Guide groove, (A)...Axis line, (C)...Axis line. ] 6

Claims (1)

[Claims] An input shaft, an output shaft disposed coaxially with the input shaft, a retainer coaxially and rotatably disposed around the input shaft and the output shaft, and coaxially disposed around the retainer. It is equipped with a cylindrical member disposed so as to be able to move in the axial direction, and a plurality of rolling elements held in a cage so as to be able to rotate around its own axis, and is mounted on the input shaft or integrally therewith. A first guide surface perpendicular to the axis of the input shaft is provided on the rotating portion, a second guide surface tapered at 45 degrees is provided on the output shaft or a portion that rotates integrally with the output shaft, and the inner circumference of the cylindrical member is An annular guide groove with an arcuate cross-sectional shape is provided on the surface, the rolling element is approximately cylindrical, a rounded part is provided around the entire outer periphery of one end of the rolling element, and the axis of the rolling element is provided on the other end surface. A spherical part having a center on a line is provided, two symmetrical places of the rounded part of the rolling element are in contact with the first guide surface and the bottom of the guide groove, and the spherical part of the rolling element is brought into contact with the second guide surface. gearbox.