JPS63192686A - Automatic non-stage transmission - Google Patents

Abstract

(57) [Summary] This bulletin contains application data before electronic filing, so abstract data is not recorded.

Description

[Detailed Description of the Invention] [Field of Industrial Application] The present invention is applicable to automatic continuously variable transmissions used between the crankshaft and rear wheel axle of a bicycle, where transmission is transmitted by an endless transmission body such as a chain or belt, or for other purposes. In particular, either the driving wheel or the driven wheel connected by the endless transmission body is composed of an outer rotary body and an inner rotary body, and one of them is an input side and the other is an output side. By making the amount of eccentricity variable depending on the magnitude of the input, the gear ratio between the inner and outer rotating bodies is made variable.

[Conventional technology]

2. Description of the Related Art Conventionally available automatic transmission devices for bicycles include devices that can change the speed ratio according to the centrifugal force of the rear wheel transmitted by an endless transmission member such as a chain or belt. According to this transmission, when the centrifugal force is large, that is, when driving at high speed, the gear ratio is increased and the pedal is pressed slowly, and conversely, when the centrifugal force is small, that is, when driving at low speed, the gear ratio is changed. I keep the ratio small and pedal at high rpm.

[Problem that the invention seeks to solve]

However, according to such conventional automatic transmission devices, the gear ratio changes in proportion to the speed of the bicycle, so even when a large driving force is required or when a small driving force is sufficient, the speed change If they are the same, the gear ratios will also be the same, and as a result, there is a problem in that a desired gear ratio cannot be set regardless of the traveling speed.

The present invention has been made by focusing on the problems of the prior art, and includes a method of detecting a desired gear ratio based on the magnitude of an input and changing the gear ratio in response to this input. The purpose is

[Means for solving problems]

In the automatic continuously variable transmission of the present invention, at least one of a driving wheel and a driven wheel, which are connected by an endless transmission body such as a chain or a belt and each has a rotating shaft, is composed of an outer rotating body and an inner rotating body. do.

Between the inner and outer rotating bodies, there is an engagement member that engages with both rotating bodies while rotating and transmits rotational force from one of the two rotating bodies to the other, and engages with both rotating bodies to interlock them. The rotating body is arranged to be variable in posture between an engaged posture in which the two rotors are disengaged from each other and a released posture in which both rotors are disengaged from one of them to release the interlocking motion.

An engagement guide is disposed on the rotational movement locus of the engagement member, which changes the engagement member into an engagement attitude at the engagement position and changes the engagement member into a released attitude at the disengagement position.

Further, both the inner and outer rotating bodies are set to be eccentric in a direction intersecting a line connecting the center of the rotation axis of the driving wheel and the center of the rotation axis of the driven wheel, and the amount of eccentricity is controlled by an eccentric amount variable mechanism. Make it variable.

This eccentricity variable mechanism includes an eccentric guide that guides at least one of the inner and outer rotating bodies in the eccentric direction, and an elastic member that is located between the inner and outer rotating bodies and deforms depending on the magnitude of input to the input side. The eccentricity can be changed depending on the magnitude of the input.

[Effect]

Between the inner and outer rotating bodies, the engaging member engages with both the rotating bodies, so that rotational force is transmitted from one input side to the other output side, causing both the rotating bodies to rotate. At this time, on the movement trajectory of the engaging member between both rotating bodies, the engaging member engages with both rotating bodies at the engagement position determined by the engagement guide, and the engaging member engages with both rotating bodies at the disengagement position. The rotational force is transmitted by the engagement in the engagement position after being disengaged from the body.

At this time, the gear ratio between the two rotors is determined according to the amount of eccentricity at the engagement position of the two rotors. This will be explained next based on FIG. 1 (al (bl), which shows the principle of operation.

Here, the center lOa of the outer rotating body IO and the inner rotating body 1
) is eccentrically set by the distance shown in FIG. 1(a), and the outer rotating body 10 is set as the driving side and the inner rotating body 1) is set as the driven side.

In the same figure, the positions where the circumference of the outer rotating body 10 is divided into six equal parts are labeled with 1 to 6, and the positions of the inner rotating body 1) that are equidistant from each of these positions are labeled with a w f. will be attached. That is, the lengths of line segments 1-a, 2-b, . . . 5-f are equal. Further, the arc between position (g) and position a of the inner rotating body 1) has a length that divides the inner rotating body 1) into six equal parts.

Here, while maintaining the length of line segment 1-a (line segment l-a
can be understood as a rigid body with the same length as this. )
, when the outer rotating body 10 is rotated in the direction of the arrow to move position 1 to position 2, the position a of the inner rotating body 1) becomes position f.
It will move until it is located beyond (g). At this time, it goes without saying that the line segment 1-a has the same length as the line segment 2-b. Then, the outer rotating body 10 rotates 6 out of 360 degrees.
This means that the inner rotating body 1) has rotated by an angle larger than one-sixth of an angle, whereas the inner rotating body 1) has rotated by an angle of one-sixth. Thus, between positions 1.2 of the outer rotor 10 the rotation of the inner rotor 1) is accelerated.

Similarly, looking at FIG. 1, the speed of the inner rotating body 1) is increased between position 6 and position 3 of the outer rotating body 10, and conversely, between position 3 and position 6 of the outer rotating body 10, the speed of the inner rotating body 1) is increased. It can be seen that the inner rotating body 1) is decelerated in this case.

In addition, Fig. 1 (bl indicates both rotating bodies 10.1) are arranged concentrically, and in this case, both rotating bodies 10.1) neither accelerate nor decelerate (and the gear ratio is 1:1). It is.

From these facts, at the position between the outer rotating body IO and the inner rotating body 1), the gear ratio between the two rotating bodies 10.1) changes by changing the amount of eccentricity of both rotating bodies 10.1). It is understandable that changes occur. This invention utilizes this principle, and the eccentricity of both rotating bodies 10.1) is determined by adjusting the eccentricity of both rotating bodies 10.1) to the input side (in the example of FIGS. 1 and 2, the outer rotating body 10). ), the elastic body is automatically deformed and changed according to the magnitude of the input.

The size of the input is determined by the chain that connects the driving wheel and the driven wheel,
It is detected by the tension of an endless transmission body such as a belt, and the eccentric direction by the variable eccentricity mechanism 1 is crossed with the direction in which the tension acts, so when tension acts on the input side, a part of it acts as eccentric force. .

Then, depending on the balance between this eccentric force and the elasticity of the elastic body of the variable eccentricity mechanism, both the inner and outer rotating bodies are guided by the eccentric guide and eccentrically become eccentric. As a result, the amount of eccentricity corresponds to the tension, and as a result, a gear ratio corresponding to the tension can be automatically obtained.

〔Example〕

FIG. 2 and the following are embodiments in which the present invention is applied to a power transmission mechanism for a bicycle.

In Fig. 2, A is a driving wheel and B is a driven wheel. The driving wheel A is a large-diameter gear fixed to the crankshaft of the bicycle, and the driven wheel B is attached to the rear wheel axle of the bicycle and will be described later. It is a small diameter gear with a structure of An endless transmission body C such as a chain or a belt is stretched between the two wheels A and B to transmit the driving force of the driving wheel A to the driven wheel B. As for the endless transmission body C, a toothed belt is used in this embodiment, but a chain or other endless transmission body may be used.

In this embodiment, the automatic continuously variable transmission of the present invention is applied to driven wheels B. That is, FIGS. 3 to 5 are specific examples thereof. Here, a rotating shaft 14 is rotatably fitted onto a fixed shaft 13 that is a rear wheel shaft, and a ring 16 having teeth 15 on the outer periphery is screwed onto the outer periphery of the rotating shaft 14. , the rotating shaft 14 and the ring 16 are configured to rotate together, and together constitute the inner rotating body 1) of the present invention. This inner rotating body 1) corresponds to the inner rotating body 1) in FIG. 1 showing the principle of the present invention.

A fixed piece 17 is fixed to the fixed shaft 13, and a movable piece 18 having a circular outer circumference is arranged outside the fixed piece 17. The fixed piece 17 has left and right guide surfaces 19 that are parallel in FIG. The left and right opposing surfaces 22 of the formed polygonal hole 21 come into sliding contact.

A slope 23 parallel to the slope 20 of the fixed piece 17 is formed from the upper end of the opposing surface 22, and the polygonal hole 2
1 has a large vertical dimension, and a movable piece 18 can move up and down on the outside of the fixed piece 17. This movement is manifested as sliding of the opposing surface 22 with respect to the guide surface 19, and the movable piece 18 is guided by the guide surface 19 of the fixed piece 17 and moved eccentrically. Therefore, the guide surface 19 of the fixed piece 17 constitutes an eccentric guide of the present invention.

This eccentric direction, that is, the moving direction of the moving piece 18 is the driving wheel A.
With respect to a line E perpendicular to the line connecting the centers of and driven wheel B,
The upper part is slightly toward the rear, so that it is eccentric in the rear and front and lower directions when viewed from the bicycle as a whole. line F
is a line indicating the eccentric direction. Therefore, when the amount of eccentricity of the movable piece 18 becomes large, the center of the movable piece 18 is
It is designed to move backward and upward from the center of the

Further, a rubber-like elastic body 24 is interposed between the slopes 20 and 23, and the eccentricity of the moving piece 18 is maximized when the rubber-like elastic body 24 is in an unloaded state.

In FIG. 5, the position of the slope 23 indicated by the chain line is the moving piece 18.
Indicates the maximum movement of .

Then, when a large tension T is applied to the endless transmission body C, the moving piece 18 moves downward while elastically deforming the rubber-like elastic body 24 to reduce the eccentricity, and the bottom dead center shown by the solid line in FIG. The amount of eccentricity is set to 0 at . The fixed piece 17, the movable piece 18, and the rubber-like elastic body 24
The variable eccentricity mechanism 25 of the present invention is configured by the above.

A rotating ring 27 and an outer gear 2 are provided on the outer periphery of the moving piece 18.
8 is rotatably mounted via a ball bearing 29, and the rotating ring 27 and the outer gear 28 are screwed together to rotate integrally, and both 27 and 28 form the outer rotating body of the present invention. 10. Therefore, the outer rotating body 1
0 moves eccentrically together with the moving piece 18. Here, it is assumed that the teeth on the outer periphery of the outer gear 28 have various conditions such as shape, dimensions, pitch, etc., corresponding to the endless transmission body C used.

An engaging member 31 is attached to the inside of the outer gear 28 by a pin 30.
is pivoted. This engaging member 31 has a plurality of teeth 32 protruding from the tip to the middle part, and is configured so that the teeth 32 are engaged with the teeth 15 of the ring 16 by a spring 33, that is, in an engaged posture. The engaging member 31 and the inner rotating body 1) are configured like a ratchet device.

In this embodiment, eight engaging members 31 are arranged at equal intervals, and each tooth 32 is biased to engage with the tooth 15 of the ring 16, but in the disengaged position, the engagement member 31 is released from the engagement. It is supposed to be done.

That is, an engagement guide 34 is fixed to the fixed piece 17, and this engagement guide 34 has an outer circumferential circle with a fixed axis 13 degrees and an inner rotating body 1.
), and the outer periphery of the engagement guide 34 is in contact with the engagement member 31 in the detached position, and the engagement guide 34
is changed to a released position in which it is released from engagement with the inner rotating body 1). That is, the released attitude refers to the attitude in which the engaging member 31 is released from engagement with the inner rotary body 1), and conversely, the attitude in which these are engaged is referred to as the engaged attitude, and the engaging member 31 is in the engaged attitude. The position where this occurs is called the engagement position.

In this embodiment, an engagement position 36 is provided on the underside of the inner rotating body 1).
A position other than this engagement position 36 in the rotational direction is a disengagement position. Therefore, as the outer rotating body 10 rotates, the engagement member 31 engages only at the engagement position 36 to rotate the inner rotating body 1).

So, step on the bicycle pedal to rotate the drive wheel A,
When the outer rotating body 10 of the driven wheel B is rotated in the direction of arrow R by the tension T through the endless transmission body C, the engagement position 36 is reached.
In this case, the engaging member 31 engages with the outer periphery of the ring 16 to rotate the inner rotating body 1), thereby driving the rear wheel of the bicycle which rotates together with the rotating shaft 14.

Here, when the force of stepping on the pedal is increased, that is, when it is desired to increase the driving force of the rear wheels, the tension T loaded on the endless transmission body C increases, and this is input to the outer rotating body 10. Due to the relationship between the direction of the tension T and the eccentric movement direction of the outer rotating body 10, a force in a downward direction acts on the outer rotating body 10, and the outer rotating body 10 moves through the moving piece 18 to the rubber-like elastic body. 24 while being compressed and deformed.

Here, when the movable piece 18 is lowered together with the outer rotating body 10, the variable eccentricity mechanism 25 functions. That is, the facing surface 22 of the polygonal hole 21 in the movable piece 18 is the same as that of the fixed piece 17.
The outer rotating body 10 descends while compressing and deforming the rubber-like elastic body 24 while being guided by the guide surface 19 .

As a result of this descent, the state shown by the solid line in Fig. 5 and the bottom dead center shown in Figs. The state b) is reached, and therefore the gear ratio between the outer rotating body 10 and the inner rotating body 1) becomes 1:1.

Furthermore, when the force of pressing the pedal is reduced, that is, when the driving force of the rear wheels is desired to be reduced, the tension T applied to the endless transmission body C and the input to the outer rotary body IO become small. Then, the force for lowering the outer rotating body 10 as described above becomes weaker, and the elastic force of the rubber-like elastic body 24 lowers the outer rotating body lO.
The force pushing up exceeds the force pushing down, and the outer rotating body 10 rises via the moving piece 18 and moves eccentrically.

The position of the polygonal hole 21 of the movable piece 18 at this time is shown by a chain line in FIG. 5, and the positional relationship between the outer rotating body 10 and the inner rotating body 1) is as shown in FIG. 1 (al).

Therefore, with respect to the rotation of the outer rotating body 10, the inner rotating body 1)
The gear ratio changes to the speed increasing side.

The above explanation is about when the force on the pedal is maximum and when it is the minimum, but when the pedal is pressed with a force between these two, the tension T corresponding to that force becomes, and this A force is applied to lower the outer rotating body 10 in accordance with this. Therefore, the outer rotating body 10 descends to a position where this lowering force and the elastic force of the rubber-like elastic body 24 opposing it are balanced, and the outer rotating body 10 becomes eccentric. Therefore, the outer rotating body 10 and the inner rotating body 1
), the outer rotating body lO
The rotational force is transmitted from the inner rotating body 1). Thus,
The eccentric movement amount and the gear ratio based on the eccentric movement amount are determined between the maximum value and the minimum value by the pedal pedal force (i.e., the endless transmission body C).
The tension T and the input to the outer rotating body 10 change steplessly in response to the same).

Note that since the outer rotating body 10 rises along the line F shown in FIG. 5, the outer rotating body 10 is farther away than the drive wheel A on the pedal side when the gear ratio is large.

Therefore, in response to the change in the gear ratio as described above, the drive shaft A
The distance between the driven wheel B and the drive wheel B changes, causing a change in the tension of the endless transmission body C. In order to prevent this change in the tension of the endless transmission body C, the following tension maintenance mechanism is installed on the drive wheel A. will be applied. In this embodiment, this mechanism is adopted for the driving wheel A, but a mechanism for maintaining a predetermined tension between the driving shaft A and the driven wheel B may be provided.

The tension maintenance mechanism of this embodiment is shown in Figure 6.7. The tension maintenance mechanism shown here was filed in the patent application filed in 1986 by the applicant.
This is a mechanism that has already been proposed as No. 1-146733. That is, the drive shaft 46 fitted onto the crankshaft is fixed to the center of the drive disk 45, and the drive shaft 46 is fixed to the center of the drive disk 45.
A plurality of bushes 47 are provided protruding from the edges of both sides. Further, side plates 48 are arranged on both sides of the drive disk 45 so as to sandwich the drive disk 45 therebetween. A plurality of bushing windows 50 are formed in the side plate 48, and the bushing windows 50 have the same number and pitch as the bushings 47 of the drive disk 45, and have an inner diameter that allows the bushings 47 to fit loosely therein. These two side plates 48
are fixed to each other by an outer ring 41 that engages with their outer peripheries.

Teeth with which the endless transmission body C engages are formed on the outer periphery of the outer ring 41. The driving disk 45 and the side plate 48 are interlocked by a bushing 47 and a bushing window 50 that are loosely fitted into each other, and the rotational force of the crankshaft is transmitted through the driving shaft 46° and the driving disk 45. Bousoche 4
7. It is transmitted to the endless transmission body C via the side plate 48° and the outer ring 41. Reference numeral 49 denotes a center hole of the temporary 48 on the side surface, from which the drive shaft 46 penetrates and protrudes outward.

Here, in the state shown in Figure 6, the crankshaft does not rotate,
Therefore, the drive shaft 46. The drive disk 45 is in a stationary state. At this time, the outer ring 41 of the side plate 48 is held with the bushing window 50 of the side plate 48 riding on the upper side of the bushing 47 due to its own weight. In addition, the side plate 4 in this case
8 and the outer ring 41 are slightly shifted toward the driven wheel B due to the tension of the endless transmission body C.

Next, the crankshaft rotates clockwise in FIGS. 6 and 7 to drive shaft 46. When the drive disk 45 rotates together, the drive bush 47 rotates in the same direction. The state at this time is shown in FIG. The rotational movement of the drive bushing 47 rotates the side plate 48 and the outer ring 41 that are engaged through the bushing window 50. At this time, due to the balance between the reaction force caused by the tension of the endless transmission body C and the rotational movement force of the drive bushing 47, the drive bushing 47 that is loosely fitted into the bushing window 50 is
The outer ring 41 and the side plate 48 move in the direction of the arrow H by moving to the side farther away from the driven wheel B (rightward in FIG. 7). This moving distance becomes the distance shown in FIG. 7, and the endless transmission body C is pulled to the right in the figure in proportion to this moving distance.

Here, since the moving distance between the side plate 48 and the outer ring 41 is determined according to the tension of the endless transmission body C, the endless transmission body C generated by eccentric movement of the outer rotating body 10 in the driven wheel B The change in tension is absorbed by changing the moving distance in this tension maintaining mechanism. In addition, instead of this tension maintenance mechanism, an endless transmission body C
Of course, it is also possible to employ a known tension maintenance mechanism that is set midway through.

As explained above, in this embodiment, the present invention is applied to a power transmission mechanism of a bicycle, but the driving wheel and the driven wheel are connected by an endless transmission body such as a chain or a belt, and each has a rotating shaft. It is widely applicable between the two countries. Further, in the above embodiment, the present invention is applied to the driven wheel, but it can also be applied to the driving wheel, and furthermore, in both the driving wheel and the driven wheel, the outside rotating body 10 as described above is used as the input end, and the invention can be rotated inside. Contrary to using the body 1) as the output side, it is also possible to use the inner rotating body 1) as the input side and the outer rotating body 10 as the output side. Furthermore, the engaging member 31 can be pivotally connected to the inner rotating body 1) instead of the outer rotating body 10, or it can be attached to a member other than the outer rotating body 10 and configured to be detachable between the two. You can also do that. In addition, since the eccentricity variable mechanism of the present invention changes the eccentricity by adjusting the balance between the tension of the endless transmission body C and the elastic force of the rubber-like elastic body 24, a spring material can be used instead of the rubber-like elastic body 24. You can also use

〔Effect of the invention〕

As explained above, in this invention, the magnitude of the input is determined by the strength of the tension of the endless transmission body such as a chain or belt that connects the driving wheel and the driven wheel, and is determined by the eccentricity variable mechanism. Since the eccentric direction intersects the direction in which the tension acts, the relative eccentric force between the inner rotating body and the outer rotating body based on the tension of the endless transmission body and the elastic force of the elastic body of the eccentric amount variable mechanism According to the balance between the inner and outer rotating bodies, the eccentric guide guides the inner and outer rotating bodies to eccentricity, resulting in an eccentricity corresponding to the tension force. A gear ratio corresponding to body tension can be automatically obtained. Therefore, according to the present invention, the desired speed ratio can be automatically changed in accordance with the magnitude of the input.

[Brief explanation of the drawing]

Fig. 1 (al (b)) is an explanatory diagram showing the principle of the present invention, Fig. 2 is an explanatory diagram showing an outline of an embodiment of the invention, and Fig. 3 is an enlarged cross-sectional view taken along the line m-m in Fig. 2. , Figure 4 is a right side view of Figure 3, Figure 5 is a left side view of Figure 3, Figures 6 and 7.
Each figure is a side view showing the tension maintaining mechanism. A... Drive wheel, B... Driven wheel, C... Endless transmission body, 10... Outer rotating body, 1)... Inner rotating body, 13
... Fixed shaft, 14 ... Rotating shaft, 15 ... Teeth, 16
...Ring, 17...Fixed piece, 18...Moveable piece,
19... Guide surface, 21... Polygonal hole, 22... Opposing surface, 24... Rubber-like elastic body, 25... Eccentricity variable mechanism, 27... Rotating ring, 28...; Outer gear, 3
DESCRIPTION OF SYMBOLS 1... Engagement member, 32... Teeth, 34... Engagement guide, 36... Engagement position

Claims (3)

[Claims] (1) At least one of a driving wheel and a driven wheel connected by an endless transmission body such as a chain or belt and each having a rotating shaft is composed of an outer rotating body and an inner rotating body, and both the inner and outer rotating bodies are connected. an engaging position in which an engaging member that engages with both rotating bodies while rotating and transmits rotational force from one of the rotating bodies to the other is engaged with both rotating bodies and interlocks them; The engaging member is arranged to be variably arranged between a release position in which the engagement member is disengaged from at least one of the rotating bodies and the interlock is released, and the engaging member is changed to the engaged position at the engagement position on the rotational movement locus of the engaging member. In addition, an engagement guide is arranged to change the engagement member to a released position at the disengagement position, and the inner and outer rotating bodies are aligned with respect to a line connecting the center of the rotation axis of the driving wheel and the center of the rotation axis of the driven wheel. The eccentricity is set to be eccentric in intersecting directions, and the eccentricity is made variable by an eccentricity variable mechanism, which includes an eccentric guide that guides at least one of the inner and outer rotating bodies in the eccentric direction, and an eccentricity variable mechanism that guides at least one of the inner and outer rotating bodies in the eccentric direction An automatic continuously variable transmission comprising an elastic body that is located between the rotating bodies and deforms according to the magnitude of input to the input side. (2) Attach a driving wheel to the crankshaft of the bicycle, attach a driven wheel to the rotating shaft of the rear wheel of the bicycle, and hang an endless transmission body such as a belt or chain between the outer rotating body of the driven wheel and the driving wheel. An automatic continuously variable transmission according to claim 1. (3) The automatic continuously variable transmission according to claim 1 or 2, wherein the engaging member is pivotally connected to one of the inner and outer rotating bodies and can be freely engaged to and disengaged from the other.