JPH0240900B2 - JIDOHENSOKUKI - Google Patents

Description

[Detailed description of the invention] A. Purpose of the invention (1) Industrial application field The present invention relates to an automatic transmission.

(2) Conventional technology Conventionally, a rolling element such as a steel ball interposed between the input side and the output side is rotated and revolved around its own axis by the rotational force from the input side, and the revolution component of the rolling element is There is a transmission configured to transmit power to the output side.

(3) Problems to be solved by the invention However, the above-mentioned conventional gears are equipped with a manual operation mechanism for manual gear shifting, or even if equipped with an automatic gear shifting mechanism, the structure is extremely complicated. Ta. Furthermore, since it is always in sliding contact with the rolling element at one point, there is a risk of local wear. Furthermore, in order to maintain the sliding state of the rolling elements, the rolling elements are urged by a spring such as a disc spring, and there is a risk that the springs will deteriorate over time.

The present invention has been made in view of the above circumstances, and enables accurate automatic gear shifting in response to the load on the output shaft with a relatively simple configuration, and prevents local wear from occurring. Another object of the present invention is to provide an automatic transmission that eliminates the need to bias rolling elements with springs or the like that are susceptible to deterioration.

B. Structure of the Invention (1) Means for Solving the Problems The automatic transmission according to the present invention has a first transmission that extends over the entire circumference.
a fixed shaft having a guide surface at one end outer edge; an output shaft rotatably and coaxially supported by the fixed shaft; an output side having a second guide surface facing the first guide surface and surrounding the output shaft; A transmission member; each having a side wall surface inclined with respect to the circumferential direction and being engaged with a plurality of first engagement recesses provided correspondingly to the opposing surface of the output side transmission member and the output shaft; a plurality of first engagement balls that press the first guide surface of the output side transmission member toward the second guide surface side when the transmission member rotates;
An input member that can freely rotate relative to the output shaft and keep its relative position in the axial direction with the output shaft unchanged, and is arranged concentrically surrounding the output shaft; An input member that can move toward and away from the input member; an input side transmission member having a third guide surface arranged opposite to the second guide surface and surrounding the second guide surface; a spring that exerts a spring force in the direction of bringing the transmission member closer to the input member; engaged with the plurality of second engagement recesses;
a plurality of second engaging balls that determine the axial position of the input side transmission member with respect to the input member according to the load applied to the input side transmission member; and a fourth guide surface coaxially surrounding the first guide surface; a floating member that is relatively rotatably supported by the side transmission member; a cocoon that has a hemispherical part that slides on the first and fourth guide surfaces, and a hemispherical part that slides on the second and third guide surfaces at both ends of the cylindrical part; a first, The second, third, and fourth guide surfaces change the attitude of the rolling element according to the relative axial position of the input side transmission member to the input member, so that the rotation axis is output from a state where the rotation axis is parallel to the output axis. It is formed so that it can be changed to a state where it is tilted with respect to the axis.

(2) Effect According to the above configuration, the relative position in the axial direction with respect to the input side transmission member is determined according to the load on the output shaft, and the attitude of the rolling elements changes accordingly, causing the rotation to the output side transmission member, that is, the output shaft. By changing the way the components are transmitted in accordance with the posture of the rolling elements, automatic speed change is achieved in accordance with the load on the output shaft. Moreover, since the contact position between the rolling element and each guide surface changes, local wear is avoided, and the output side and input side transmission members are pressed toward the rolling element by the first and second engaging balls, and the rolling element is pressed by the spring. It becomes unnecessary to energize.

(3) Embodiment Below, an embodiment of the present invention will be described with reference to the drawings. First, in FIGS. 1 and 2, this automatic transmission has a fixed shaft 1 and a shaft disposed coaxially with the fixed shaft 1. an output shaft 2 that coaxially surrounds the output shaft 2; an input member 4 that coaxially surrounds the output shaft 2;
A separable input-side transmission member 5, a spring 6 that resiliently urges the input-side transmission member 5 toward the input member 4, a floating member 7 supported by the input-side transmission member 5 so as to be relatively rotatable, and a fixed It is provided with a plurality of rolling elements 8, for example, six, which contact the shaft 1, the output shaft 2, the input side transmission member 5, and the floating member 7 at four points.

The fixed shaft 1 is basically formed into a cylindrical shape with a bottom, and the outer edge of one end (closed end) of this fixed shaft 1 has a
A first guide surface 9 is formed over the entire circumference. The first guide surface 9 has a vertical cross-section shaped like an arc concave inward.

The output shaft 2 includes a shaft portion 2a that rotatably passes through the closed end of the fixed shaft 1, a connecting flange portion 2b extending radially outward from the outer surface of the shaft portion 2a, and a cylindrical portion 2c. The shaft portion 2a is rotatably supported by the fixed shaft 1 via a thrust bearing 10.

The output side transmission member 3 coaxially surrounds the shaft portion 2a of the output shaft 2 and is basically formed in a cylindrical shape.
At the outer edge of the fixed shaft 1 side end of the output side transmission member 3, a second guide surface 11 opposite to the first guide surface 9 is provided.
are provided around the entire circumference. Furthermore, the second guide surface 11 has a vertical cross-sectional shape that is an arc concave inward.

In FIG. 3, the connecting flange 2 on the output shaft 2
A plurality of first engaging recesses 12 and 13 corresponding to each other are provided on the opposing surfaces of the output side transmission member 3 and the first engaging ball 14 between the both engaging recesses 12 and 13.
are respectively engaged. Each engagement recess 12, 13
has side wall surfaces 12a and 13a that are inclined so as to gradually approach each other from the center toward both sides in the circumferential direction with the engaging ball 14 in between, and are formed symmetrically with respect to a plane orthogonal to the axis of the output shaft 2. Ru. According to this structure, when the output side transmission member 3 is subjected to a strong force in the circumferential direction and tries to rotate, each engagement ball 14 has side wall surfaces 12a, 12a facing each other on one diameter line thereof.
13a, the power is transmitted to the output shaft 2, and the output side transmission member 3 is separated from the connecting flange 2b of the output shaft 2 in the axial direction, so that the second guide surface 11 and the rolling elements 8 are constantly in contact with each other. .

The input member 4 is formed in a cylindrical shape coaxially surrounding the connecting flange 2b and cylindrical portion 2c of the output shaft 2, and is supported by the cylindrical portion 2c of the output shaft 2 via a bearing 15 so as to be relatively rotatable. .

The input side transmission member 5 is basically formed in a cylindrical shape with a flange 5a facing the input member 4 at one end, and is rotatably disposed coaxially surrounding the output side transmission member 3 and the fixed shaft 1. be done. A third guide surface 16 surrounding the second guide surface 11 is provided on the inner edge of the collar 5a of the input power transmission member 5, and the third guide surface 16 is provided on the fixed shaft 1 side. It is formed in a tapered shape that becomes larger in diameter as it approaches.

A spring bearing member 18 is rotatably supported on a portion of the fixed shaft 1 near the other end via a bearing 17 . A coiled spring 6 is interposed between the spring receiving member 18 and the input side transmission member 5, and the spring force of the spring 6 moves the input side transmission member 5 in a direction approaching the input member 4. is energized.

In FIG. 4, a plurality of second engaging recesses 19 and 20 are provided on the opposing surfaces of the input member 4 and the collar portion 5a of the input side transmission member 5, and a plurality of second engaging recesses 19 and 20 are provided in correspondence with each other. The second engaging balls 21 are engaged with the respective second engaging balls 21 . Each second engagement recess 19, 20
has side wall surfaces 19a and 20a that are inclined so as to gradually approach each other from the center toward both sides in the circumferential direction with the second engagement ball 21 in between, and are perpendicular to the axes of the input member 4 and the input power transmission member 5. It is formed symmetrically with respect to the plane. According to this structure, as the input member 4 rotates, each of the second engaging balls 21 moves toward the side wall surfaces 1 facing each other on one diameter line thereof.
9a and 20a, power is transmitted to the input side transmission member 5, and the input side transmission member 5 moves in a direction away from the input member 4 while resisting the spring force of the spring 6 according to the load applied thereto.

Between the input side transmission member 5 and the fixed shaft 1, there is a basically cylindrical floating member 7 which is prevented from moving outward by a retaining ring 22 fitted on the inner surface of the input side transmission member 5. The floating member 7 is arranged so as to be freely rotatable relative to the transmission member 5.
Fixed shaft 1 allowing axial movement and rotational movement of
A bearing member 23 is mounted to support the shaft.

A fourth guide surface 24 that faces the third guide surface 16 and coaxially surrounds the first guide surface 9 is provided on the floating member 7 over the entire circumference.
The guide surface 24 is formed in a tapered shape that becomes larger in diameter as it goes inward in the axial direction.

The rolling element 8 has hemispherical parts 8b at both ends of the cylindrical part 8a,
8c is formed in a cocoon shape integrally provided with the fixed shaft 1 and the output side transmission member 3 at equal intervals in the circumferential direction.
placed around. One hemispherical portion 8b of this rolling element 8 is in sliding contact with the first and fourth guide surfaces 9, 24, and the other hemispherical portion 8c is in sliding contact with the second and third guide surfaces 11, 16. Moreover, each rolling element 8 is
It is held in a cage 25 so as to be able to rotate about its rotation axis C. The retainer 25 includes a plurality of, for example, six retaining protrusions 25b protruding from the inner surface of a ring portion 25a that is in sliding contact with the inner circumferential surface of the input side transmission member 5, at equal intervals in the circumferential direction. The moving body 8 is held between two circumferentially adjacent holding protrusions 25b, 25b. Furthermore, the retainer 25 is arranged between the collar portion 5a of the input side transmission member 5 and the floating member 7.

First, second, third and fourth guide surfaces 9,1
1, 16, and 24 are each rolling element 8 according to the axial position of the input side transmission member 5, that is, the third guide surface 16.
It is formed to change the posture of the body. That is,
As shown in FIG. 1, when the input side transmission member 5 is at the farthest position from the input member 5, each rolling element 8 is in a posture with its rotation axis C parallel to the axis of the output shaft 2. In such a state, the contact position of the hemispherical portion 8c of the rolling element 8 with the second guide surface 11
The contact position P2 between P1 and the third guide surface 16 is
Located at the same distance from the rotation axis C, each rolling element 8 functions in the same way as a normal roller bearing, and only rotates around the fixed shaft 1 and the output side transmission member 3 together with the retainer 25, and the output side transmission member No rotational force is transmitted to 3. Furthermore, when the input side transmission member 5 is at the closest position to the input member 4 as shown in FIG. . In such a state, the second half of the hemispherical portion 8c of the rolling element 8
The contact position P1' with the guide surface 11 and the contact position P2' with the third guide surface 16 are located at different distances from the rotation axis C, and the rolling elements 8 are located at different distances from the fixed axis 1.
The rotational force is transmitted to the output side transmission member 3 by the differential operation at that time.

Next, the operation of this embodiment will be explained. First, when no load is applied to the output shaft 2, no load is applied to the input side transmission member 5.
As shown in FIG. 5, the input side transmission member 5 is positioned closest to the input member 4 due to the spring force of the spring 6. That is, each second engagement ball 21 is in a state of being sunk between the second engagement recesses 19 and 20. In this state, each rolling element 8 is pressed by the fourth guide surface 24 of the floating member 7 that moves in the axial direction together with the input side transmission member 5, and each rolling element 8 tilts its rotation axis C with respect to the axis of the output shaft 2. It becomes a posture.

When a rotational force is input from the input member 4 in this state, the rotational force is transmitted to the input side transmission member 5 via the engagement ball 21, and from the third guide surface 16 of the input side transmission member 5 to the rolling element 8. is transmitted to. At this time, the distance between the contact position P1' of the rolling element 8 with the second guide surface 11 and the rotation axis C is larger than the distance between the contact position P2' with the third guide surface 16 and the rotation axis C. , the rolling element 8 rotates around its axis and revolves, and transmits rotational force to the output side transmission member 3 by differential action, and the rotational force is transmitted to the output shaft 2 via the plurality of first engagement balls 14, and this The rotational speed of the output shaft 2 at this time is the maximum.

Next, assume that a large load is applied to the output shaft 2. In this case, since a large load is also applied to the input side transmission member 5, the input side transmission member 5 resists the spring force of the spring 6 due to the action of the second engagement ball 21 and the second engagement recesses 19, 20. input member 4
as shown in FIG. Due to this movement of the input side transmission member 5,
Each rolling element 8 is pressed by the third guide surface 16 and assumes a posture with its rotation axis C parallel to the axis of the output shaft 2.

When a rotational force is input from the input member 4 in this state, the rotational force is transmitted to the input side transmission member 5 via the second engagement ball 21, and is rotated from the third guide surface 16 of the input side transmission member 5. It is transmitted to the moving body 8. At this time, the contact position of the rolling element 8 with the second guide surface 11
The distance between P1 and the rotation axis C is the same as the distance between the contact position P2 with the third guide surface 16 and the rotation axis C, and no differential action by the rolling elements 8 occurs. Therefore, the rolling elements 8 only rotate around the fixed shaft 1 and the output side transmission member 3 together with the cage 25, and no rotational force is transmitted from the rolling elements 8 to the output side transmission member 3, and the output shaft 2 The rotation speed is zero.

In this way, depending on the magnitude of the load applied to the output shaft 2, the rolling elements 8 steplessly change their posture from the parallel posture shown in FIG. 1 to the inclined posture shown in FIG. The rotational speed of the second gear is changed steplessly and automatically from zero to the maximum value, and automatic gear shifting can be performed over a wide range.

Moreover, the rolling element 8 contacts the first, second, third and fourth guide surfaces 9, 11, 16, 24 at four points,
Since the contact position changes according to the change in the attitude of the rolling element 8, each of the first guide surfaces 9, 11, 16, 24
And wear of the rolling elements 8 at the same point is suppressed.

Further, the output side transmission member 3 is moved to the rolling element 8 by the action of the first engagement ball 14 and the first engagement recesses 12 and 13.
The input side transmission member 5 is also urged to be in constant contact with the second engagement ball 21 and the second engagement recesses 19, 2.
Since the rolling element 8 is always urged to be in sliding contact with the rolling element 8, it is not necessary to use a spring such as a disc spring, and there is no need to consider the durability of the disc spring or the like.

Further, since the rolling elements 8 are cocoon-shaped, a relatively large number of rolling elements 8 can be mounted relative to the outer diameter of the entire automatic transmission, and the transmission force can be increased accordingly.

C. Effects of the Invention As described above, according to the present invention, the first guide surface provided on the fixed shaft, the fourth guide surface provided on the floating member, the second guide surface provided on the output side transmission member, and the input side transmission The attitude of the rolling element is changed by bringing the hemispherical parts at both ends of the cocoon-shaped rolling element into contact with the third guide surface provided on the member and moving the input side transmission member in the axial direction according to the load applied to the output shaft. change,
Since the speed is changed by the differential operation of the rolling elements, the overall structure can be simplified by mainly using rotational transmission by abrasion pressure welding, and automatic speed change can be performed over a wide range.

In addition, the engagement balls are engaged with a plurality of engagement recesses provided correspondingly on the opposing surfaces of the input member and the input side transmission member, and the input member of the input side transmission member is engaged with the engagement balls in accordance with the load applied to the input side transmission member. Since the axial position relative to the output shaft is determined, it is possible to accurately automatically shift the speed according to the load on the output shaft with a simple configuration.

Furthermore, the output side transmission member and the input side transmission member are pushed in the direction of sliding contact with the rolling elements by the first engagement recess and the first engagement ball, as well as the second engagement recess and the second engagement ball, so that the disc spring There is no need to use a spring such as the like for biasing, and there is no need to consider the deterioration of the spring.

Moreover, since the rolling element contacts the first to fourth guide surfaces at four points and changes the contact position, it is possible to prevent the rolling element and each guide surface from being locally worn.

[Brief explanation of drawings]

The drawings show one embodiment of the present invention, and FIG. 1 is a longitudinal sectional view of the output shaft in a state where the rotational speed is zero, FIG. 2 is a sectional view taken along the line -- of FIG. FIG. 4 is an enlarged sectional view taken along the - line in FIG. 1, FIG. 5 is a longitudinal sectional view corresponding to FIG. 1 when the rotational speed of the output shaft is at the maximum. . DESCRIPTION OF SYMBOLS 1... Fixed shaft, 2... Output shaft, 3... Output side transmission member, 4... Input member, 5... Input side transmission member, 6... Spring, 7... Idle member, 8... Rolling element, 8a... Cylindrical part,
8b, 8c... Hemispherical portion, 9... First guide surface, 11...
Second guide surface, 12, 13...first engagement recess, 14
...First engagement ball, 16...Third guide surface, 18...Spring receiving member, 19, 20...Second engagement recess, 21...Second
Engagement ball, 24...fourth guide surface, 25...retainer, C
...rotation axis.

Claims (1)

[Claims] 1. A fixed shaft having a first guide surface extending over the entire circumference at one end outer edge; an output shaft rotatably and coaxially supported by the fixed shaft; a second guide surface facing the first guide surface;
an output-side transmission member having a guide surface and surrounding the output shaft; and a plurality of output-side transmission members each having a side wall surface inclined with respect to the circumferential direction and provided corresponding to the opposing surface of the output-side transmission member and the output shaft, respectively. a plurality of first engagement balls that are engaged with the first engagement recesses of the output transmission member and press the first guide surface of the output transmission member toward the second guide surface when the output transmission member rotates; relative to the output shaft; An input member that is freely rotatable and keeps its axial relative position with the output shaft unchanged, and is arranged concentrically surrounding the output shaft; An input member that is arranged opposite to the input member so that it can move toward and away from the input member. an input side transmission member having a third guide surface surrounding the second guide surface; a plurality of second springs each having a side wall surface inclined with respect to the circumferential direction and provided corresponding to the opposing surface of the input member and the input side transmission member;
a plurality of second engagement balls that are engaged with the engagement recesses and determine the axial position of the input transmission member relative to the input member according to the load applied to the input transmission member; and a plurality of second engagement balls that coaxially surround the first guide surface. a floating member having four guide surfaces and relatively rotatably supported on the input side transmission member; a hemispherical portion slidingly in contact with the first and fourth guide surfaces; and a hemispherical portion slidingly contacting the second and third guide surfaces; A plurality of rolling elements are formed in a cocoon shape and are rotatably held around the axis of rotation by a cage that coaxially surrounds the output shaft and is supported for relative rotation on the input side transmission member. and; the first, second, third and fourth guide surfaces adjust the attitude of the rolling element according to the relative axial position of the input side transmission member with respect to the input member, so that the axis of rotation thereof is parallel to the output shaft. 1. An automatic transmission characterized in that the automatic transmission is configured to change from a state in which the axis of rotation is tilted to a state in which the axis of rotation is inclined with respect to an output shaft.