Pedal displacement type crank rotation driving mechanism

Abstract

The present invention pertains to a crank rotation drive mechanism provided with left and right pedals that alternately apply external forces to a pair of left and right crank arms attached to a crankshaft, and an output unit that rotates integrally with the crankshaft. [Problem] To provide a crank rotation drive mechanism that can be used for a long period of time without requiring a large effort. The invention provides a pedal displacement type crank rotation driving mechanism (Z). The present invention is provided with: a pair of left and right crank arms CA and a crank rotation shaft CX2 fixed to a crank shaft CX1 axially supported by a frame F and the like; a pair of left and right swing arms A axially supported by a fixed swing fulcrum shaft A4 at a position away from the crank shaft CX1; and a first slider S1 axially supported by the crank rotation shaft CX2 and reciprocatingly moving in the longitudinal direction of the swing arms A. A second slider (S2) that is in contact with or not in contact with the first slider (S1) and intermittently reciprocates; and a pedal (P) that is attached to a second slider front block (S21) and that rotates a crankshaft (CX1) while drawing a substantially elliptical trajectory by swinging a swinging arm (A). The pedal-shifting-type crank rotation drive mechanism (Z) provides a rotation output to an output unit (5). (The main purpose of the invention) the invention is not only suitable for common bicycles, but also suitable for weak people or commercial tricycles, fitness equipment, labor-saving equipment, devices and the like.

Description

Technical Field

[0001] The present invention relates to a pedal-shifting crank rotation drive mechanism, which includes left and right pedals that alternately apply external force to a pair of left and right crank arms mounted on a crankshaft, and an output section that rotates integrally with the crankshaft. Background Technology

[0002] Conventionally, as a related crank rotation drive system, there exists, for example, the system shown in Patent Document 1 (refer to paragraphs

[0011] to

[0021] and...). Figure 1 , Figure 2 ).

[0003] The system includes a pedal shaft 10 fixed to the frame 3 and not rotating on its own, guide components 11a and 11b that rotate within a certain angle around the pedal shaft, and pedals 12a and 12b that are mounted on the guide components 11a and 11b and can rotate on their own and move up and down.

[0004] Guide grooves 13a and 13b are formed on the inner sides of guide members 11a and 11b, respectively, and protruding members 26a and 26b integrally formed on crank cams 22a and 22b are respectively accommodated in the guide grooves. Crank cams 22a and 22b are integrally assembled on crankshaft 20, and gear 21 is integrally assembled on crankshaft.

[0005] If pedals 12a and 12b move up and down, protruding parts 26a and 26b rotate along guide grooves 13a and 13b, while crank cams 22a and 22b, crankshaft 20, and gear 21 rotate. If gear 21 rotates, gear 31 meshing with it rotates in the opposite direction, and sprocket 32, which is integral with gear 31, also rotates.

[0006] The fixed shaft 30 is assembled to the frame 3 in a fixed manner and does not rotate; only the gear 31 and sprocket 32 ​​rotate. Therefore, the gear 31 and sprocket 32 ​​are assembled to the fixed shaft 30 via bearings.

[0007] When one pedal 12a is at top dead center and the other pedal 12b is at bottom dead center, the device operates smoothly if the protruding parts 26a and 26b of the crank cams 22a and 22b are tilted at a certain angle θ3 in the direction of rotation and through the vertical center line of the crankshaft 20.

[0008] This structure allows for the application of seatless bicycles that move forward by reciprocating the pedals up and down. The smooth movement of the pedals easily converts the reciprocating motion into rotational motion. Furthermore, the user rides standing up, thus achieving a full-body workout compared to riding a seated bicycle.

[0009] Prior art document Patent document 1: Japanese Patent Publication No. 2010-508191 However, in the aforementioned conventional crank-driven system, the movement trajectory during pedal lifting and lowering is a repetitive up-and-down circular arc centered on the pedal shaft 10. Therefore, the user's foot movement becomes unnatural, unlike the flexion and extension of a human foot during walking. Consequently, the foot's power cannot be fully utilized, and the foot tires easily, making prolonged use difficult.

[0010] As mentioned above, while the overall structure of conventional crank-rotation drive systems, such as the fixed pedal shaft 10, is simple, there are still problems to be solved regarding the convenience of the device. Therefore, in this technical field, there is a need for a crank-rotation drive system or mechanism that requires little pedal force and can be used for extended periods. Summary of the Invention

[0011] Feature structure The pedal-shifting crank rotation drive mechanism of the present invention is characterized by comprising: A pair of left and right crank arms are respectively fixed to the two ends of a crankshaft that can be rotatably mounted on a frame or the like, and have a 180-degree phase angle difference in motion and perform an action. A crank rotation shaft is disposed at the front end of each of the left and right pairs of crank arms; A pair of left and right swing arms, the pair of left and right swing arms are axially supported by a fixed swing fulcrum shaft, the fixed swing fulcrum shaft is fixedly arranged on the frame etc. at a position that is separated from the crank shaft and exceeds the length of the crank arm; A pair of left and right first sliders are rotatably supported on the crank rotation shaft and held on the swing arm. They can reciprocate along the long side of the swing arm. When the direction of the fixed swing fulcrum axis along the long side is taken as the rear end side and the opposite direction is taken as the front end side, the front end abutting part and the rear end abutting part of the first slider that move together along the long side are kept facing opposite directions. A pair of second sliders, one on the left and one on the right, are held on the swing arm and are capable of reciprocating along the long side of the swing arm. The front and rear abutment portions of the second sliders, which move integrally along the long side, are held facing each other at a predetermined interval. The second sliders reciprocate intermittently in the same direction and within a movable range, accompanying the reciprocating movement of the first sliders, through contact or non-contact between the opposing front and rear abutment portions of the first sliders, or contact or non-contact between the opposing rear abutment portions of the first and second sliders. A pair of left and right pedals are mounted on the front block of the second slider. The front block of the second slider is configured to be located on the front side of the swing arm, closer to the front end of the first slider, during the reciprocating movement of the first slider. The left and right pedals, through their alternating movements, cause the left and right swing arms to swing alternately. This swinging motion, in conjunction with the swinging motion, simultaneously applies rotational force to the crank arm via the first slider while drawing a deformed elliptical trajectory, and also applies rotational force to the crank shaft. The pedal-shifting crank rotation drive mechanism provides rotational output to the output section that rotates integrally with the crankshaft.

[0012] The effects of the invention The pedal-shifting crank rotation drive mechanism of this structure is configured such that a first slider is rotatably supported on a crank shaft located at the front end of a pair of left and right crank arms, and a reciprocating swing arm holds the first slider so that it can move along its long side. The front end abutment portion and the rear end abutment portion of the first slider, which move integrally with the first slider, are held to face opposite directions.

[0013] A second slider is provided on each of the left and right swing arms. The front and rear abutment portions of the second sliders, which move integrally with each other, are maintained at a predetermined interval and face each other. Accompanying the reciprocating movement of the first slider, the second sliders move intermittently within their movable range by contacting or not contacting each other, either with the front and rear abutment portions positioned opposite each other. The amplitude of this movement is less than the amplitude of the movement of the first slider, with fewer interruptions.

[0014] The left and right pairs of second sliders have a second slider front block. During the reciprocating movement of the first slider, the second slider front block is located on the front end side of the swing arm, which is closer to the front end of the first slider. The left and right swing arms swing alternately by the alternating action of the left and right pairs of pedals mounted on the second slider front block, thereby imparting rotational force to the crank shaft. At the same time, the trajectory of the pedal axis is formed in coordination with the swing of the swing arm, depicting a deformed elliptical circular trajectory with the upper and lower major axes greatly expanded on the short axis side of the crank arm as a whole.

[0015] In this configuration, along the long side of the swing arm, the front end face of the first slider can be designated as the front abutment portion of the first slider, and the rear end face can be designated as the rear abutment portion of the first slider. Furthermore, the rear end face of the front block of the second slider can be designated as the front abutment portion of the second slider.

[0016] The reciprocating distance of the first slider becomes the diameter of the crank circle depicted by the trajectory of the crank's rotation axis. In this application, a crank with a pair of crank arms of a predetermined length and a crank rotation axis is implemented. Here, it is referred to as the implemented crank, and the rotation trajectory of the crank's rotation axis is referred to as the implemented crank circle. The front block of the second slider, which is mounted on the pedal, is located at the front end of the swing arm compared to the first slider. For example, during the period when the first slider reciprocates on the swing arm in accordance with the movement of the pedal from the start to the end of the movement, the front block of the second slider approaches the front end block of the swing arm until it abuts due to the direction of the action force.

[0017] When the swing arm swings, contact is limited to the contact between the front end or rear end of the first slider and the front end or rear end of the second slider. The second slider moves in the same direction along its long side through this contact, linked with the first slider. A pedal is provided in front of the second slider, which is located at the front end of the swing arm, to transmit input to the swing arm, the first slider, the crank shaft, and the crank arm.

[0018] According to this structure, the alternating movements of the left and right swing arms and the pair of left and right pedals correspond to and continuously reciprocate at a predetermined angle. This causes the first slider to reciprocate through its component force, while simultaneously the crank arm and crank shaft rotate continuously in a predetermined direction, and the crank shaft also rotates continuously in the same direction, thus generating rotational output. At this time, the second slider, through the contact and non-contact between its two contact points and the two contact points of the first slider, intermittently reciprocates in the same direction along the long side of the swing arm, accompanying the movement of the first slider.

[0019] During the reciprocating swing motion of the pair of left and right swing arms, the pair of left and right pedals installed on the front block of the second slider can also move back and forth along the long side of the swing arm, thereby changing the distance from the swing fulcrum of the swing arm, i.e. the fixed swing fulcrum axis, to the pedal.

[0020] Furthermore, the pedal-shifting crank rotation drive mechanism of this structure is based on a configuration where the direction of the basic line connecting the fixed oscillating pivot axis and the crank axis is horizontal, and the following description will primarily follow this configuration. However, depending on the implementation method and application, without altering the overall coherence of this structure, by deflecting the entire structure, including the horizontal direction, by a predetermined angle with the crank axis as the center or the fixed oscillating pivot axis as the center, i.e., by installing and using the structure with the deflection angle when viewed from the crank axis direction, a wider range of applications can be provided.

[0021] Next, when the direction of the basic line connecting the fixed oscillating pivot axis and the crank axis is set to horizontal, in this structure, the top dead center and bottom dead center of the crank rotation axis are the points of tangency with the crank circle drawn from the fixed oscillating pivot axis to the upper and lower tangent lines drawn from the crank circle. Conversely, the uppermost position in the crank circle is designated as the uppermost point, and the lowermost position as the lowermost point. Here, when the rotation direction of the crank rotation axis is set from the upper dead center through the lowermost point towards the bottom dead center, the uppermost point is the position that has exactly passed the upper dead center, and the lowermost point is the position that has not yet reached the bottom dead center. Therefore, the range within which the swing arm can be oscillated and the crank arm rotated by the action of one pedal is essentially the range within the crank circle from the point where the upper dead center passes through the pedal's component force that does not generate a component force to the lower dead center that does not generate a component force.

[0022] However, the practical application of this structure with a pair of crank arms having a 180-degree phase angle difference is that the point symmetrical to the point 180 degrees backward from the bottom dead center on the crank circle, with the crank axis as the center, is the point symmetrical to the bottom dead center from the top dead center when the line connecting the uppermost and lowermost points is used as the reference line for the crank circle. At this point, the pedal action position corresponding to this point is the pedal action start point.

[0023] However, in this structure, the range of rotation of the crank shaft when each pedal is actuated is determined by appropriately setting the distance between the front end abutment and the rear end abutment of the second slider to a predetermined distance. The front end abutment and the rear end abutment of the second slider are held together by the second slider in a direction facing each other. That is to say, it is possible to set the range of rotation of the crank shaft when the pedal is actuated from the line symmetrical point of the aforementioned top dead center to the bottom dead center, or from the uppermost point (or its vicinity) to the lowermost point (or its vicinity). Both are possible, but this is set as a design specification.

[0024] Next, let's reset the crankshaft rotation range during pedal actuation to be from the highest point to the lowest point (hereinafter referred to as "this case"). When one pedal actuation ends, the crankshaft rotation on the opposite side is at the starting point of rotation. Then, as the pedal actuation on the other side continues (called the actuation stroke), the crankshaft rotation on this side is passively rotated, that is, the stroke from the lowest point on the crank circle to the starting point of rotation, i.e., the highest point (called the return stroke). Then, the cycle of the crankshaft rotation trajectory formed by the combined actuation stroke and return stroke of each pedal is the cycle from the highest point to the highest point, and if the start of the return stroke is taken as the reference, it is the cycle from the lowest point to the lowest point.

[0025] Furthermore, in this case, during the stroke of one pedal, the crank rotation axis rotates towards the lowest point via the midpoint of the stroke furthest from the fixed pivot point in the crank circle along the aforementioned basic line direction. Also, when the end face of the first slider side of the second slider front block is used as the second slider front end contact point, during the initial rotation from the start of the stroke to the aforementioned midpoint on the crank circle, the pedal is mounted on the second slider front block and held at the front end of the swing arm. The second slider front block has a second slider front end contact point that is already in contact with the first slider front end contact point at the start of the stroke.

[0026] Next, in this state, the pedal is activated and the swing arm is rotated. The force of the action is transmitted through the crank shaft to move the first slider, thereby causing the second slider to be closest to the front end of the swing arm's range of motion, i.e., the front end block of the swing arm.

[0027] In this way, during the initial rotation of the pedal stroke, the pedal axis and the swing arm work together to trace a bulging curved trajectory downwards in the front direction.

[0028] Then, during the remaining rotation of the crank arm, which constitutes the first half of its rotational stroke, as the crank axis moves along the path of the crank circle to its lowest point, only the first slider moves towards the fixed pivot point axis. Meanwhile, the pedal, mounted on the front block of the second slider, is in contact with the front end block of the swing arm due to the opposite direction of the force, thus ending the stroke. As a result, the pedal axis, under the combined action of the swing arm's swing, traces a partial arc trajectory with a radius equal to the distance to the pedal axis, centered on the fixed pivot point axis. At this point, before the crank axis supporting the first slider reaches its lowest point, the rear end face of the first slider remains close to, but not yet in contact with, the rear end face of the second slider. In other words, before the crank axis on one side reaches its lowest point, the rear end face of the first slider on the same side does not contact the rear end face of the second slider; this is a crucial condition, the first prerequisite.

[0029] However, in this situation, the distance between the front end abutment and the rear end abutment of the second slider is set so that even if an attempt is made to continue the action of one side pedal, it will immediately occur. The rear end abutment of the first slider on that side will abut against the rear end abutment of the second slider. The force exerted by the crank rotation force on the first slider on the rear end is opposite to the force exerted by the crank rotation force on the front end of the second slider, thus preventing the action from being stopped. This prevents the movement of the axis of the crank rotation shaft supporting the first slider from significantly exceeding the lowest point and ending the stroke. Only through the subsequent action of the other side pedal does the return stroke of the crank rotation shaft on that side begin. With the rear end abutment of the first slider on that side still abutting against the rear end abutment of the second slider, they both begin to move towards the rear end of the swing arm.

[0030] Based on these structural conditions, the range of movement of the first slider in the long direction, as appropriately set according to the user and usage conditions as described later, the respective lengths of the first and second sliders, the required lengths of other components, and various appropriate and necessary clearances, the swing arm has a specified length. Furthermore, to achieve miniaturization, the swing arm is not unnecessarily lengthened, but rather designed to be the minimum necessary length possible. For example, compared to conventional crank-driven mechanisms in bicycles, the long-side length of the swing arm-type pedal-shifting crank-driven mechanism in this structure is inherently more likely to be longer, potentially causing fundamental problems such as interference between the operating foot and the bicycle's front wheel. To prevent such problems, controlling the swing arm length to the minimum necessary length possible is a crucial condition, namely the second prerequisite.

[0031] Therefore, after comprehensive consideration, the design specifications that meet the first and second preconditions are taken as the basic idea of ​​this structure.

[0032] Here, when pedaling again with the foot as if riding a bicycle, for example, the travel distance from the pedal start point corresponding to the uppermost point of the left and right crank arms and crank rotation axis on the crank circle to the pedal end point corresponding to the lowermost point is defined as the pedal travel distance, and the travel distance from the end point to the start point is defined as the return travel distance before the pedal travel distance. The return travel distance is achieved through the pedal travel distance on the opposite side.

[0033] By pressing the pedal on the opposite side, during the rotation of the crank arm in the return stroke, for example, in the initial part of the return stroke of the crank arm rotating upwards from the lowest point of the pedal on the implementing crank circle to the line connecting the fixed pivot axis and the crank axis via the swing arm, initially, the rear end face of the first slider abuts against the rear end face of the second slider on the swing arm, keeping the second slider as a whole from abutting against the rear end block on the fixed pivot axis of the swing arm, and moves towards the closest position to the fixed pivot axis. At the same time, the pedal mounted on the front block of the second slider also moves the same distance towards the fixed pivot axis to the closest position. As a result, the pedal axis, combined with the swing of the swing arm, traces an arc of about a quarter of a long circle bulging towards the rear end of the basic line, the degree of bulging being approximately the radius of the implementing crank circle. At this time, the long side direction of the crank arm and the swing arm is also consistent with the direction of the line connecting the fixed pivot axis and the crank axis via the swing arm.

[0034] In the latter part of the return stroke of the swing arm up to the top point, the ideal action is that only the first slider moves towards the front end of the swing arm A based on the trajectory of the crank circle. The front end contact point of the first slider, i.e., the front end face, remains in a state of not contacting the front end contact point of the second slider, i.e., the rear end face, but is closest to it, thus ending the return stroke.

[0035] However, during this period, i.e. the latter part of the return stroke, the second slider remains stationary in the long side direction of the swing arm. Therefore, the pedal axis of the pedal mounted on the front block of the second slider, combined with the swing of the swing arm, traces a partial arc-shaped trajectory with the fixed swing fulcrum axis as the center, the distance to the pedal axis as the radius, and the rear end direction upward.

[0036] In this scenario, by setting a second prerequisite—keeping the swing arm length at the minimum necessary length—the first slider's front end face abuts against the second slider's rear end face near the top dead center, not during stroke transitions, but during the latter part of the return stroke, before the crankshaft reaches its highest point. The second slider's front block has a pedal that traces an upward-curving arc and swings to this point. This causes a sharp change in the direction of the pedal's axis trajectory, creating a discontinuity. While this isn't ideal for pedal movement, it provides a good opportunity to time subsequent pedaling actions.

[0037] Based on the current results, when the rotation range of the crank axis during pedal operation is set from the highest point to the lowest point, after completing one cycle, although there are abrupt changes in the direction of the pedal axis's motion trajectory, combined with the swing arm's swing, an expansion portion is formed in front of the swing arm pointing downwards. After the lowest point of the crank axis's return stroke, the degree of expansion is the displacement distance in the basic line direction corresponding to the movement amplitude towards the rear end, which is approximately the radius of the crank circle used in the implementation. Overall, it depicts a deformed elliptical circumference that is not found in the conventional fixed-pivot swing arm type crank rotation drive system shown in Patent Document 1. The folding and forward movement of the user's foot can easily adapt to this circumference. The short axis of this circumference has a larger front-to-back amplitude, while the top and bottom are the long axis.

[0038] Regarding the minimum necessary length of the swing arm, firstly, the narrow angle (called the basic narrow angle) formed by the basic line passing through the fixed swing fulcrum axis and the crank axis, and the line passing through the same fixed swing fulcrum axis and the uppermost point of the implemented crank circle, and the diameter of the implemented crank circle are defined. Thus, the distance from the fixed swing fulcrum axis to the crank axis is uniquely determined. In the implemented crank circle, when the crank rotation axis is located at the position farthest from the fixed swing fulcrum axis, i.e., at the intersection of the implemented crank circle and the extension line connecting the fixed swing fulcrum axis and the crank axis, viewed from the fixed swing fulcrum axis, the first slider is located at the distance from the fixed swing fulcrum axis to the crank axis plus the radius of the implemented crank circle. A second slider front block is positioned at the front end of the first slider, and a swing arm front block is positioned further forward of the first slider, with appropriate gaps between them. In this state, the length of the swing arm is set to the minimum necessary length.

[0039] Furthermore, the basic narrow angle refers to the narrow angle formed by the lines connecting the uppermost point, the lowermost point, and the axis of the fixed swing fulcrum, respectively, and the basic line. Ideally, this range is between 20 and 35 degrees. As discussed later, the implementation using the crank circle diameter is based on the length of each crank arm appropriately set according to the user and usage conditions during typical crank pedal operation. Compared to implementing the crank circle diameter, the setting of the basic narrow angle offers a degree of flexibility.

[0040] Next, for example, the range of rotation of the crank rotation axis when the pedal is pressed (operated) is set from the highest point to the lowest point. Regarding the gap between the front end abutment of the second slider and the rear end abutment of the second slider in this case, considering that the length of the swing arm is set to the minimum necessary length according to the second condition mentioned above, in the implementation of the crank circle, when the crank rotation axis on one side reaches the lowest point of the end of the pedal stroke, at this moment, the rear end face of the rear end abutment of the first slider on the same side does not abut against the rear end abutment of the second slider. In addition, if the pedal operation continues, the rear end abutment of the first slider on that side will also immediately abut against the rear end abutment of the second slider. Therefore, at this moment, the rear end abutment of the second slider is located further back of the first slider and is separated from the first slider by the minimum necessary gap.

[0041] On the other hand, at this time, the front block of the second slider is pressed against the front end block of the swing arm due to the stepping of the pedal installed on it. Therefore, the interval between the front end abutment part and the rear end abutment part of the second slider is taken as the set interval in this case.

[0042] Therefore, when the rotation range of the crank axis during pedaling is set from the highest point to the lowest point, the interval between the front and rear abutment parts of the second slider in the swing arm, which maintains the minimum necessary length, is the distance the crank axis supporting the first slider moves along the long side of the swing arm from the point furthest from the fixed pivot point to the lowest point—that is, the distance the first slider moves in the latter part of the pedal stroke—plus the width of the first slider along its long side. This forms the mechanism of this structure, ensuring that during the pedal stroke starting from the highest point, the first slider almost always ends its movement at the lowest point and will not significantly exceed the lowest point.

[0043] In this structure, when the pedal is in its pedal stroke, it slides towards the front end along the swing arm. During the initial part of the pedal's return stroke, it slides towards the fixed rotation axis along the swing arm. Thus, the pedal axis traces a deformed elliptical trajectory with a large front-to-back amplitude, where the front and back are the minor axes and the top and bottom are the major axes.

[0044] However, although there is a proportional relationship between the distance the pedal axle travels towards the rear end and the expansion amplitude of the pedal axle's circular trajectory in the basic line direction, the two are not equal in length. The main factor determining the expansion amplitude of the pedal axle is the displacement of the rotation axis in the basic line direction when it rotates towards the rear end on the crank circle used for implementation. Its maximum value is the expansion amplitude in the same direction. Therefore, similar to the expansion amplitude of the rotation axis towards the rear end, the expansion amplitude of the pedal axle's circular trajectory in the basic line direction, when the necessary minimum clearance is set to an extremely small value, is naturally almost equal to the radius of the crank circle used for implementation.

[0045] Therefore, by appropriately setting the crank circle diameter relative to the crank circle diameter of the comparison object below, the front and rear expansion range of the overall pedal axis circle trajectory can be made almost the same as or greater than the radius of the conventional ordinary crank circle, i.e., the length of the ordinary crank arm.

[0046] On the other hand, if, as mentioned above, the pedal travel is taken from the line symmetrical point of the so-called top dead center on the crank circle to the bottom dead center, and the return travel is taken from the line symmetrical point of the bottom dead center (which is further back than the bottom point) to the top dead center, then the distance the first slider moves in the first part of the return travel, which mainly determines the forward and backward amplitude of the corresponding pedal axis circle trajectory in the long side direction, will be significantly smaller than the same distance when the pedal travel is set from the top point to the bottom point and the return travel is set from the bottom point to the top point.

[0047] Therefore, this is the main reason why, in this structure, it is preferable to change the motion travel from the so-called upper dead point to the lower dead point, and to set the return travel from the lower dead point to the upper dead point.

[0048] Regarding the effect of this structure, the pedal itself moves up and down with the swing arm, while simultaneously moving along its long side. Thus, for example, when the crank arm is rotated by stepping on the pedal with the foot using the swing arm, it creates a circular trajectory that is easily adapted to the folding and forward movement of the user's foot. This allows for pedaling along a rotational trajectory that reduces operator foot fatigue. This is the first effect of this structure.

[0049] Next, the rotational drive mechanism of this structure will be explained. Between the left and right pedals, the first slider, which is held by the crank arm and the swing arm near the uppermost point of the crank circle, moves along the track along the long side of the swing arm under the action of the pedal's pedaling action, which is mounted on the front block of the second slider held by the swing arm. The front block of the second slider, which abuts against the pedal at the front end of the first slider, maintains the increased driving rotational torque due to the effect of a small lever, while moving to the front end of the swing arm, and the crank arm rotates around the crank shaft.

[0050] The pedal installed on the second slider front block moves to the front end of the movement range during the initial rotation of the crank arm from the starting point of the action to the direction of the line connecting the fixed swing fulcrum axis and the crank axis. During the remaining rotation of the crank arm during the pedaling (action) stroke, due to the direction of the action force, it will stop at the front end of the swing arm. The crank rotation axis will be pedaled to the lowest point of the crank circle. Therefore, the large lever effect of the swing arm will increase the driving rotation torque around the crank axis.

[0051] Furthermore, the overall purpose of this structure is to solve the biggest problem of traditional crank-driven rotary drives, namely, to improve the efficiency of rotary drives by combining the force distribution effect of pedaling actions, including the uppermost point, which is equivalent to the top dead center of a normal crank, and the vicinity therein, as well as the lowermost point, which is equivalent to the bottom dead center of a normal crank.

[0052] Therefore, compared with the traditional fixed-pivot swing arm crank rotation drive system, this system does not have the approximately elliptical motion trajectory of the pedal with a large forward and backward amplitude. With almost the same degree of efficiency improvement in rotation drive, combined with the first effect mentioned above, it can greatly reduce the load on the crankshaft rotation operation when the user uses foot force. This is the second effect of this structure.

[0053] Furthermore, when this structure is applied to a bicycle, similar to the crank pedaling of a regular bicycle, the directional operation of the ankle and the natural forward movement of the foot using the lower limb joint as a fulcrum make rotational drive relatively easy. Once the crank arm begins to rotate, the inertial force acts on the riding body, allowing for easy and continuous rotation, thus enabling the enjoyment of the first and second effects for an extended period. On the other hand, this structure's pedal-shifting rotary drive mechanism is particularly effective when riding a bicycle on a gentle but continuous uphill section where inertial force cannot be utilized.

[0054] In structures where movement or pedaling is delegated to the arms and feet, this structure's features can be maximized and its applications broadened by appropriately adjusting the direction of movement (pedaling), making it particularly suitable for this purpose. Furthermore, by effectively combining installation with angle adjustment from the crankshaft direction perspective, this structure can be applied to an even wider range of uses. On the other hand, in structures where movement does not rely on the arms and feet, this structure can also be applied to various purposes by combining appropriate setting of the movement direction with installation with angle adjustment from the crankshaft direction perspective.

[0055] Feature structure The pedal-shifting crank rotation drive mechanism of the present invention may include an elastic support member and a support abutment member. In order to respond to the change in the gap between the first slider and the front block of the second slider by abutting and compressing accordingly, and simultaneously transmitting a force that moves the second slider within a movable range in the long-side direction toward the front end, the elastic support member has a front end abutment portion held by either the first slider or the second slider. The support abutment member also has a front end abutment portion held by either the second slider or the first slider.

[0056] This structure is primarily designed to create a supported state. It includes an elastic support member spanning the front blocks of the first and second sliders. The elastic support member has a front-side abutment portion, which may or may not abut against either the front-side abutment portion of the first slider or the front-side abutment portion of the second slider. For example, if the first slider has an elastic support member, then the front block of the second slider has a corresponding support abutment member. The front-side abutment end of the elastic support member becomes the front-side abutment portion of the first slider, and the rear-side abutment end of the support abutment member becomes the front-side abutment portion of the second slider. The front-side abutment portions of both can abut or not abut against each other. Even in this case, the front-side abutment portion of the second slider and the rear-side abutment portion of the second slider, which are the rear-side abutment portions of the support abutment member, are held on the swing arm at a predetermined interval in the long side direction, facing each other, while the front-side abutment portion and the rear-side abutment portion of the first slider face opposite directions.

[0057] Furthermore, in this structure, it is preferable to set the travel distance of the pedals mounted on the left and right sides of the second slider front block after they begin to move from the highest point to the lowest point, and to set the return travel distance from the lowest point to the highest point. The main reason for this is that it increases the forward and backward amplitude of the pedal axis circular trajectory, making it easier to adapt to the folding and forward movement of the foot, especially when pedaling.

[0058] The effects of the invention In this structure, by setting the stroke from the highest to the lowest point and the return stroke from the lowest to the highest point, the length of the swing arm is kept to a minimum. Simultaneously, an elastic support component is introduced so that when the pedal begins to move—for example, when a person presses down on the pedal—the pedal position is as far away as possible from the fixed pivot point of the swing arm. This allows for the utilization of the swing arm's greater leverage effect. Furthermore, it increases the driving rotational torque around the crankshaft generated by the force component of the pedaling motion from the start of pedaling, particularly at the highest point (equivalent to the top dead center of a standard crank), including its vicinity, and at least the lowest point (equivalent to the bottom dead center of a standard crank), increasing the torque input to the crankshaft in its vicinity. This is the first effect of equipping this structure with an elastic support component.

[0059] Furthermore, as mentioned earlier, during one stroke of the return stroke, the trajectory of the pedal axis appears at the point where the pedal's direction of travel changes abruptly just before being depressed. This is because there is no obstruction between the first slider S1 and the front block S21 of the second slider, and just before the end of the return stroke, it comes into contact with the front end of the second slider, which has swung to this point on the swing arm. A second effect of this structural feature is the introduction of an elastic support component to form a supported state. This component absorbs and moderates the transmitted force while simultaneously advancing the contact point and accelerating the transmission of force from the first slider to the second slider, thus achieving smooth pedal movement and a smooth pedal axis trajectory. Attached Figure Description

[0060] Figure 1 This is an exploded perspective view showing the appearance of the pedal-shifting crank rotation drive mechanism provided in the first embodiment; Figure 2 This is an exploded perspective view showing the main components of the pedal-shifting crank rotation drive mechanism; Figure 3 This is a schematic diagram showing the pedal trajectory of a pedal-shifting crank rotation drive mechanism; Figure 4 This is an explanatory diagram illustrating the operation of a pedal-shifting crank rotation drive mechanism; Figure 5 This is an explanatory diagram illustrating the operating mode of the main components of the pedal-shifting crank rotation drive mechanism; Figure 6 This is a schematic diagram illustrating the operating force of the crank pedal; Figure 7 This is a perspective view showing the main components of the pedal-shifting crank rotation drive mechanism according to the first embodiment; Figure 8 This is a schematic diagram showing the trajectory of the pedal in the first embodiment; Figure 9 This is an explanatory diagram of the operation mode of the pedal shifting type crank rotation drive mechanism according to the first embodiment; Figure 10 This is a perspective view showing the main components of the pedal-shifting crank rotation drive mechanism according to the second embodiment; Figure 11 This is a schematic diagram showing the trajectory of the pedal in the second embodiment; Figure 12 This is an explanatory diagram illustrating the operation mode of the pedal-shifting crank rotation drive mechanism according to the second embodiment. Detailed Implementation

[0061] First Implementation Method summary based on Figures 1 to 9The basic technical content of this invention relates to a pedal-shifting crank rotation drive mechanism Z. This pedal-shifting crank rotation drive mechanism Z includes a pair of left and right crank arms CA and a crank rotation shaft CX2, a pair of left and right swing arms A, a first slider S1, a second slider S2, and a pedal P. The left and right swing arms A are axially supported on a fixed swing fulcrum shaft A4, which is located at a distance from the crank shaft CX1 exceeding the length of the crank arms CA. The first slider S1 is axially supported on the crank rotation shaft CX2 and reciprocates along the long side of the swing arm A. The second slider S2 abuts or does not abut as the first slider S1 reciprocates, and intermittently reciprocates in the same direction within its movable range. The pedal P is mounted on the front block S21 of the second slider, causing the swing arms A to swing, tracing an approximately elliptical trajectory, while simultaneously rotating the crank shaft CX1. The pedal-shifting crank rotation drive mechanism Z is used to apply rotational output to an output section 5 that rotates integrally with the crank shaft CX1. This invention achieves the following two main objectives simultaneously.

[0062] The first objective is to design a mechanism in which a pedal P is rotatably mounted on the pedal shaft in a conventional crank, thereby significantly improving the rotational drive efficiency of pedal action during pedal P pedaling, at least at the so-called top dead center and bottom dead center, as well as near the top dead center and bottom dead center.

[0063] The second objective is to make the movement of pedal P not a reciprocating swing along the same track, but a circular track movement that is easily adapted to by the folding and forward movement of the human foot.

[0064] This invention achieves both objectives simultaneously. Specifically, the forward and backward movement of the pedal P is set to a range that, while smaller than a human walking stride, matches as closely as possible to the folding and forward thrusting movements of the foot. Furthermore, the trajectory of the pedal axis PX is formed as an approximately elliptical circle with the vertical axis as its major axis, thereby reducing the power burden of repetitive pedal movements. For example, it can reduce the burden on the hip joint and other parts of the foot when moving the pedal P, achieving smooth and continuous movement.

[0065] First, based on Figures 1 to 6 The following describes an embodiment of the invention when applied to a bicycle. However, for ease of understanding of the following description, the state of the pedal axis PX from the pedal pedaling start point to the position at the front end of the swing arm A under the functional action of the pedal foot or swing support member 3, etc., is exemplified as an example (hereinafter referred to as "this example").

[0066] The bicycle frame F supports a crankshaft CX1, a pair of crank arms CA with a phase angle difference of 180 degrees and located in opposite left and right positions, a crank rotation shaft CX2 (equivalent to the pedal shaft of a regular bicycle), and a pedal P. The crankshaft CX1 is rotated by the rotation of the two crank rotation shafts CX2 around it, and the output of this rotation causes the wheels to rotate. The crank mechanism used in this implementation has a pair of crank arms CA and a crank rotation shaft CX2. The specified length of the crank arms CA is shorter than that of a regular bicycle. As mentioned earlier, this is referred to as the implemented crank, and the rotation trajectory of the crank rotation shaft CX2a is called the implemented crank circle.

[0067] At a position beyond the length of the crank arm CA at a distance from the crank shaft CX1 of the crank used in this embodiment, there is a fixed swing fulcrum shaft A4, and a pair of left and right swing arms A that can swing back and forth at a specified angle. The first slider S1 moves back and forth relative to the track provided in the long side direction, and is rotatably engaged with the crank rotation shaft CX2 in the crank used in this embodiment through the sleeve S11, etc.

[0068] Here, the first embodiment is referred to again as this first embodiment. In this first embodiment, the second slider S2 reciprocates relative to the swing arm A along the same track as the track of the first slider S1 provided in the long side direction. In order to make the second slider S2 rigid, a second slider front block S21 and a second slider rear block S22 are provided. The second slider rear block S22 is held on the swing arm A at a predetermined distance from the first slider S1 moving in the long side direction.

[0069] On the other hand, the first slider S1 and the second slider S2 each have a front end abutment portion. That is, the front end abutment portion S1f of the first slider S1 is provided at the front end abutment surface in the front end direction, and the front end abutment portion S2f of the second slider is provided at the rear end abutment surface of the second slider front block S21.

[0070] The rear end face of the first slider S1 is defined as the rear end abutment part S1r, and the front end face of the rear block S22 of the second slider is defined as the rear end abutment part S2r. In the long side direction, the front end abutment part S1f and the rear end abutment part S1r of the first slider are held facing opposite directions. The front end abutment part S2f of the front block S21 and the rear end abutment part S2r of the rear block S22 of the second slider are arranged facing each other on the swing arm A at a predetermined interval. Furthermore, the left and right pairs of second sliders S2 have a front block S21 and a rear block S22 connected across the first slider S1 by a connecting member 21. In the bifurcated left and right pairs of second sliders S2, a pedal shaft P10 and a freely rotatable pedal P are mounted on the front end of the front block S21. Through the alternating pedaling action of the left and right pedals P, the crank arm CA and the crank rotation axis CX2a rotate from the uppermost point through the aforementioned intermediate point to the lowermost point.

[0071] Based on this, such as Figure 3 or Figure 6 As shown, in this embodiment, the range of the pedal stroke of one side P is set to the distance from the uppermost point PH to the lowermost point PL along the trajectory of the crank rotation axis CX1a, and the range of the return stroke of the other side P is set to the distance from the lowermost point PL to the uppermost point PH.

[0072] One reason for this design is based on the reliability of the pedal P's pedaling action. Specifically, the bottom dead center is the point of tangency between the lower tangent line drawn from the fixed pivot axis AX to the crank circle and the crank circle itself. Therefore, the deviation from the position of the swing contact angle relative to the swing arm A is relatively large, making it prone to uncertainty due to pedal P's movement deviation. On the other hand, if the lowest point PL is chosen, the pedal P's stroke can be accurately completed. Other reasons, as mentioned earlier, include increasing the front-to-back width of the circular trajectory of the pedal axis PX, which is particularly beneficial when pedaling with the foot, facilitating the folding and forward movement of the foot.

[0073] In the implementation on a bicycle, the travel distance between the pedaling start point (located at approximately the uppermost point of the crank circle, which corresponds to the top dead center of a standard crank) and the pedaling end point (located at approximately the lowermost point, which corresponds to the bottom dead center) of the crank circle is defined as the pedaling travel distance. The travel distance between the end point and the start point is defined as the return travel distance before the pedaling travel distance. The return travel distance is achieved by the pedaling travel distance on the opposite side.

[0074] To achieve the first objective, the rotary drive mechanism of this solution is as follows. The first slider S1 is held on a pair of left and right swing arms A supported by a fixed swing fulcrum shaft A4. The fixed swing fulcrum shaft A4 is positioned at a distance from the crank shaft CX1 exceeding the length of the crank arm CA. Simultaneously, the first slider S1 is held on the crank arm CA near the uppermost point on the crank circle. The second slider front block S21 is always positioned further forward than the first slider S1 and is held by the swing arms A. By pressing the pedal P mounted on the second slider front block S21, for example, when the direction of the pedal force is the direction of the reference line connecting the uppermost point PH and the lowermost point PL on the crank circle, the generated pedal force component can at least improve the rotary drive efficiency of the pedal action at the uppermost point PH and the lowermost point PL, which are equivalent in position to the so-called top dead center and bottom dead center in a conventional crank, as well as near the uppermost point PH and the lowermost point PL.

[0075] Therefore, compared with the driving torque in a conventional crank as a comparison object, in the structure of this embodiment (hereinafter referred to as "this structure"), it is possible to completely avoid the pedal P of the so-called top dead center and bottom dead center. In addition to the pedaling force effect, compared with a conventional crank, the driving torque around the crank shaft CX1 of this structure can exceed the driving torque in a conventional crank in the range from the uppermost point PH to the lowermost point PL due to the larger lever effect of the swing arm A.

[0076] The following describes the structural features of this first embodiment for achieving the second objective. Continuing with this example... Figures 1 to 6 This document describes in detail the components of the basic pedal shifting type crank rotation drive mechanism Z (hereinafter referred to as "this mechanism Z") provided in this first embodiment.

[0077] like Figure 1 As shown, in this mechanism Z, a pedal P is installed on the swing arm A, which is linked to the crankshaft CX1 and the crank rotation shaft CX2. By alternately pressing the left and right pedals P, the swing arm A is made to swing back and forth. The pedal P is configured to move back and forth along the swing arm A.

[0078] In this example, such as Figure 3 and Figure 4 As shown, during the pedal stroke (action) from the highest point PH to the lowest point PL, i.e., during the pedal axis PX's movement from... Figure 3During the movement from point F to point H, only the first slider S1 reciprocates towards the front end of the swing arm A, thus completing the stroke. In other words, while maintaining the longest possible distance from the fixed swing fulcrum axis A4, the pedal P and the second slider S2 remain at the front end of the swing arm A. Under the swinging action of the swing arm A, the pedal axis PX traces an arc-shaped curved trajectory with the fixed swing fulcrum axis A4 as the center and the distance to the pedal axis PX as the radius.

[0079] If pedal P on one side of the swing arm A is pressed, the other side of the swing arm A will rise. During the first half of the return stroke of the crankshaft CX2 on the other side, when crank arm CA rotates a quarter turn, the first slider S1 on that side abuts against the rear block S22 of the second slider, and the second slider S2 is pulled back towards the fixed swing fulcrum axis A4. Therefore, pedal P on the other side is pulled back towards the fixed swing fulcrum axis A4 and moves towards the front end of swing arm A during the next quarter turn. When viewed along the crankshaft CX1, the movement trajectory of pedal axis PX is as follows... Figure 3 As shown, in conjunction with the swing of the swing arm A, it forms an approximately elliptical arc that bulges outwards towards the rear end, with the bulge amplitude being approximately the radius of the crank circle used in the implementation, i.e., the arm length of the crank used in the implementation.

[0080] Returning to this example, as mentioned earlier, by appropriately setting the diameter of the crank circle to match the pedaling (action) stroke and return stroke, when the crank rotation axis CX2a rotates once, the rotation trajectory of the pedal axis PX, under the swinging action of the swing arm A, forms a trajectory with a large forward and backward movement amplitude, which is not found in conventional fixed-pivot swing arm type crank rotary drive systems. That is, a symmetrical deformed elliptical trajectory with the vertical axis as the major axis. This trajectory has a small bulge arc-shaped curved portion on the front end side of the swing arm A and a deformed elliptical arc portion on the rear end side, and the bulge amplitude of this portion is approximately the radius of the crank circle. The combined bulge degree is close to the arm length of a normal crank, and the folding and forward movement of the user's foot easily adapts to this trajectory. This is the basic structural content of this first embodiment to achieve the second objective.

[0081] Furthermore, when pedal P is activated, the range of motion and flexibility required to withstand prolonged foot pedaling are limited. Therefore, in the pedal operation of a typical crank, the length of the crank arm is appropriately set according to the user and usage conditions. In contrast, in this mechanism Z, to achieve miniaturization, the distance from the crank shaft center CX1a to the crank rotation axis CX2a—that is, the arm length of the implemented crank—is set to a length equal to or less than the length appropriately set for each crank arm in a typical crank. Therefore, the arm length of the implemented crank is also appropriately set according to the user and usage conditions, and the movement amplitude of the first slider, which is equal to the diameter of the implemented crank circle, is also set accordingly. In addition, in this case, the rotation trajectory of the crank rotation axis corresponding to the appropriately set ordinary crank arm is referred to as the comparison crank circle.

[0082] exist Figure 3 In this diagram, trajectories T1 and T2 are compared. T1 is the trajectory of the crank circle formed by the crank rotation axis CX2a in this example, while T2 is the trajectory of the comparison crank circle formed by the rotation of a normal crank. As mentioned above, the implemented crank circle must have a diameter smaller than the comparison crank circle. However, even if its diameter is considerably smaller than a human walking stride, it is preferable to be as close as possible to the front-to-back width that matches the user's foot folding and forward movement. Additionally, the trajectory of the pedal axis PX is also shown in this diagram. When the crank rotation axis CX2 rotates one revolution, the rotation trajectory of the pedal axis PX is formed at a position slightly forward-biased relative to the circular trajectory of the crank rotation axis CX2a.

[0083] Figure 6 This illustrates the relationship between the pedal force of P and the driving rotational torque generated around the crankshaft CX1 on the trajectory T1 (implemented as a crank circle) of the crankshaft rotation axis CX2a in this example. For example, let the direction of the pedal force Fa of P be the direction of the line (reference line) connecting the uppermost point PH and the lowermost point PL of the rotation trajectory of the crankshaft rotation axis CX2a. Define a force acting on the intersection point P1 of the trajectory T1 with the line passing through the crankshaft axis CX1a and forming an arbitrary angle θ with the reference line. Here, α represents the angle between the centerline of the swing arm A and the line connecting the fixed swing fulcrum axis AX and the crankshaft axis CX1a.

[0084] Since the downward pedaling force Fa acts on the pedal axis PX, the pedaling component Fm1 perpendicular to the swing arm A on the pedal axis PX is: According to Fm1, there is a force parallel to Fm1 at the intersection point P1, and this force is... ,Right now The force exerted is k. k is the leverage ratio, expressed as L2 (length of line segment AX-PX) / L1 (length of line segment AX-P1). Additionally, the force at intersection P1 in the tangential direction to trajectory T1 is... .

[0085] Here, if r1 represents the radius of trajectory T1 and r2 represents the radius of trajectory T2, then the driving torque Ma1 at the intersection point P1 about the crankshaft CX1 is expressed as: (1) When θ is zero, the basic narrow angle between line segment AX-CX1a and line segment AX-PH is set as α0. As θ increases from 0 degrees to 90 degrees, L1 increases, but conversely, α decreases from α0 to 0 degrees.

[0086] α0 is determined by the relative relationship between the fixed swing fulcrum axis AX and the trajectory T1. However, considering the length of the swing arm A, the size of each component, as well as the stepping position, height, stroke, etc., it is preferably between 20 degrees and 35 degrees, and the angle with better effect is about 25 degrees to 30 degrees.

[0087] In this example, assuming the pedal travel has been maximized from the starting point of pedaling to the front end of the swing arm A, if we limit the pedal travel to the pedal P, that is, the area from the uppermost point PH to the lowermost point PL of the crankshaft axis CX2a, then L2 is constant, therefore the leverage ratio is... The maximum torque is achieved at the uppermost point PH and the lowermost point PL. When the crankshaft axis CX2a is at the uppermost point PH or the lowermost point PL, since the pedal P is located at the front end of the swing arm A, a greater rotational torque can be applied to the crank arm CA from the beginning of the pedal stroke.

[0088] In other words, the closer the pedal shifting rotary drive mechanism Z shown in this example is to the uppermost point PH and the lowermost point PL, which are equivalent to the top dead center and bottom dead center of a normal crank, the larger the leverage ratio k is. Due to the leverage ratio effect produced by this lever action, the driving rotation torque also increases. Therefore, combining it with the pedaling action component force becomes a well-adapted and reasonable means.

[0089] Furthermore, when θ moves from the first half of the pedal stroke beyond 90 degrees from the midpoint to 180 degrees from the lowest point PL, which is the second half of the pedal stroke, the change in the driving torque around the crankshaft CX1a is symmetrical about the line segment AX-CX1a. The overall increase in driving torque around the crankshaft CX1 during the pedal stroke is approximately twice that before θ reaches the 90-degree midpoint.

[0090] The above explanation pertains to the point where the pedal axle PX extends from the starting point of pedal application to the front end of the swing arm A in this example. However, through... Figure 7 In the original first embodiment showing the structure of the main components, the pedal P is mounted on the second slider front block S21. The second slider front block S21 has a second slider front end abutment portion S2f that is in contact with the first slider front end abutment portion S1f at the start of the action. The pedal P is held at the front end of the swing arm. In this state, the pedal P is actuated, causing the swing arm A to rotate. The first slider S1 is moved via the crank rotation shaft CX2, thereby causing the second slider S2 to move as a whole on the swing arm A until it moves to the swing arm front end block A1, which is closest to the front end of the movement range. That is, in the first half of the pedal stroke, L2 is not constant and changes with θ, just like L1. When θ is 0 degrees, i.e., at the uppermost point of the crank circle, L2 is the smallest, and the leverage ratio is... Not at its maximum, the change in driving rotational torque around crankshaft CX1 is not symmetrical in the first and second halves of the pedal stroke, with the basic line passing through the fixed pivot point axis AX and crankshaft axis CX1a as the boundary.

[0091] However, in this case, before θ reaches 90 degrees, the pedal P gradually approaches the front end of the swing arm A. When θ is at the 90-degree baseline, L2 is at its maximum. Even if the leverage ratio k is not sufficient in the first half of the pedal stroke, it is still greater than 1, and the leverage effect still exists. Furthermore, in the latter half of the pedal stroke where θ exceeds 90 degrees, the pedaling force continues to act. When the pedal P is at the front end of the movable range of the swing arm A, L2 is at its longest and its length is constant. As L1 decreases, the driving torque near the lowest point increases significantly. Therefore, even in this case, combined with the pedaling force, it can still increase the driving torque around the crankshaft CX1 throughout the entire pedal stroke.

[0092] crank arm like Figure 1 As shown, a pair of crank arms CA are mounted on the frame F of a bicycle or similar device. The left and right crank arms CA have a 180-degree phase angle difference and extend radially from the crankshaft CX1. A sprocket 50 is mounted on the crankshaft CX1, which acts as an output unit 5 to transmit the rotation of the crankshaft CX1 to, for example, the rear wheel. Furthermore, at the front end of each of the left and right crank arms CA, a crank rotation shaft CX2 extends outward parallel to the crankshaft CX1.

[0093] Swing arm A fixed fulcrum shaft A4, different from the crankshaft CX1, is provided in the frame F at a position exceeding the length of the crank arm CA. The swing arm A is rotatably supported on this fixed fulcrum shaft A4. Exemplarily, the fixed fulcrum shaft A4, like the crankshaft CX1, is located on the basic line and at the rear end. A first slider S1, a second slider S2, and a pedal P are held on this swing arm A.

[0094] First slider like Figure 1 and Figure 2 As shown, the first slider S1 is rotatably mounted on the crank shaft CX2 of the crank arm CA via bearing S11 and the like. The first slider S1 is externally inserted into two guide rods A3, which serve as tracks on the swing arm A, via linear bearings and the like. Thus, the first slider S1 moves smoothly back and forth on the swing arm A as the crank arm CA rotates.

[0095] Second slider The second slider S2, driven by the reciprocating motion of the first slider S1, is also reciprocally mounted on the two guide rods A3 of the swing arm A via linear bearings or the like. The second slider S2 includes a second slider front block S21 and a second slider rear block S22, which are connected in a forked shape by a connecting member 21. The second slider front block S21 has a pedal P supported on its upper shaft.

[0096] pedal The self-rotating pedal P is installed on the front block S21 of the second slider S2 in a position that does not interfere with the first slider S1 and the swing arm A.

[0097] like Figure 7 and Figure 9 As shown, in the pedal-shifting crank rotation drive mechanism Z of this first embodiment, there is no moving obstacle between the first slider S1 and the second slider front block S21, and their relative positional relationship is easily changed. Therefore, in order to make it easier (even slightly) for the second slider S2 holding the pedal P to slide (or shift) forward of the swing arm A when the pedal P is pressed, the fixed swing fulcrum axis AX is tilted relative to the crank axis CX1a so that it is positioned above. That is, the basic line on one side of the fixed swing fulcrum axis A4 is offset from the horizontal position by an appropriate angle β in the direction towards the uppermost point PH, not with the fixed swing fulcrum axis AX as the center, but with the crank axis CX1a as the center. The basic line is offset together without changing its relationship with the overall structure, that is, it is installed with a certain angle offset when viewed in the direction of the crank axis CX1.

[0098] In this way, when the pedal P is pressed in the early part of the pedal stroke, the first slider S1 is moved by the swing arm A and the crank shaft CX2, which in turn moves the second slider S2 to abut against the front end block A1 of the swing arm. During this process, the pedal axis PX and the swing arm swing together to draw a bulging curved trajectory downward in the front direction.

[0099] The pedal stroke corresponds to the first half of the crank arm CA's rotation. In the remaining rotation of the subsequent pedal stroke, until the crankshaft axis CX2a reaches its lowest point PL following the trajectory of the crank circle used in the implementation, that is, from... Figure 8 and Figure 9 From point G to point H, only the first slider moves towards the fixed swing fulcrum axis A4. The pedal P, mounted on the front block S21 of the second slider, abuts against the front block A1 of the swing arm due to the opposite direction of the force. In this state, at the instant the rear end contact point S1r of the first slider and the rear end contact point S2r of the second slider come into contact, the movement is stopped, thus ending the pedaling stroke. As a result, the combination of the pedal axis PX and the swing of the swing arm A traces a partial circular arc trajectory centered on the fixed swing fulcrum axis AX and with a radius equal to the distance to the pedal axis PX. At this moment, before the axis CX2a of the crank rotation shaft CX2 supporting the first slider S1 reaches its lowest point PL, the rear end contact point S1r of the first slider, i.e., the rear end face, remains in a state of not contacting the rear end contact point S2r of the second slider, but is closest to it.

[0100] However, during the pedal stroke, the crank rotation axis CX2a, which is acted upon by the pedal P on the depressed side, moves past the lowest point PL due to inertia and towards the bottom dead center. Even if the crank arm CA wants to continue rotating, the first slider S1 on that side will immediately come into contact with the rear end contact point S2r of the second slider, thus stopping the movement. The movement of the crank rotation axis CX2a, which supports the first slider S1, will not significantly exceed the lowest point PL, thus ending the pedal stroke. Next, when the pedal P on the other side is depressed, the return stroke of the aforementioned crank rotation axis CX2a begins. The rear end contact point S1r of the first slider on that side, while in contact with the rear end contact point S2r of the second slider, begins to move towards the rear end of the swing arm A in the return stroke. The pedal P is pulled back towards the fixed swing fulcrum axis A4.

[0101] In other words, at this time, the pedal stroke begins simultaneously by pressing the other pedal P. The crank rotation axis CX2a on the other side exceeds the uppermost point PH. When the first slider S1 and the front end of the second slider S2f are in contact, the other pedal P begins the pedal stroke by being pushed towards the front end of the swing arm A.

[0102] On the other hand, the return stroke of pedal P during its return action is explained as follows. When the opposite pedal P is depressed, this pedal P completes its return stroke. During the rotation of crank arm CA in the return stroke, for example, from the lowest point PL (the end point of depressing in the crank circle) to the line connecting the fixed pivot axis AX of swing arm A and the crank axis CX1a, crank arm CA rotates upwards. At the beginning of this return stroke, the rear end face of the first slider on swing arm A, which moves towards the rear end, abuts against the rear end face of the second slider on the rear end face S2r. The second slider S2 remains in a state where it does not abut against the rear end block A2 on the fixed pivot axis A4 side of swing arm A, and moves towards the fixed pivot axis A4 side to its closest position. Accompanying this movement, pedal P, mounted on the front block S21 of the second slider, also moves the same distance to its closest position to the fixed pivot axis A4. As a result, as described above, the combination of the pedal axis PX and the swing arm A creates an arc of about a quarter of a deformed ellipse bulging towards the rear end of the basic line, the degree of which is approximately the radius of the crank circle used in the implementation.

[0103] Next, in the latter part of the return stroke of the crank arm CA rotating to the uppermost point PH, only the first slider S1 moves towards the front end of the swing arm A based on the trajectory of the crank circle. Ideally, the front end face of the first slider is kept from contacting the front end face of the second slider S21, which is the rear end face, and moves to the position closest to it and ends the return stroke.

[0104] However, during this period, that is, in the latter part of the return stroke, the second slider S2 remains stationary in the long side direction of the swing arm A. Therefore, the pedal axis PX of the pedal P mounted on the front block S21 of the second slider, combined with the swing of the swing arm A, traces a partially circular curved trajectory in the rear end direction with the fixed swing fulcrum axis A4 as the center and the distance to the pedal axis PX as the radius.

[0105] Furthermore, in this situation, as described above, when the pedal is about to reach the uppermost point PH in the latter part of the return stroke, the first slider S1 moving towards the front end and the second slider front block S21 swinging upwards directly abut against each other, causing a sharp change in the trajectory direction of the pedal axis PX, resulting in a discontinuity. While this is not ideal for pedal movement, it can be a good opportunity to grasp the timing of subsequent pedaling actions.

[0106] In this structure, although the first slider S1, which is supported on the crank rotating shaft CX2, performs a continuous sliding reciprocating motion, the second slider front block S21, which is equipped with the pedal P, moves intermittently along the swing arm A by only contacting the first slider S1. At the same time, the pedal P can perform both sliding and rotating motions.

[0107] The first effect of this structure is as follows: Figure 8 As shown, the pedal axis PX, combined with the swing of the swing arm A, traces a deformed elliptical circular trajectory with the upper and lower axes as the major axes. The degree of expansion of this trajectory is generally above the radius of the crank circle used in the implementation, and the diameter of the crank circle used in the implementation is approximately the length of a normal crank arm. This trajectory is slightly inclined in the front end direction of the long side of the swing arm A. When the foot presses down on the pedal P using the swing arm A to rotate the crank arm CA, the folding and forward movement of the foot easily adapts to this circular trajectory, enabling pedal movements that reduce foot fatigue for the operator.

[0108] As a second effect of this structure, the uppermost point PH and the lowermost point PL are the approximate start and end points of the pedal stroke, thus enabling pedaling that completely avoids the top dead center and bottom dead center. Overall, by utilizing the motion component generated during pedaling, and especially by leveraging the large lever effect of the swing arm A during the remaining rotation of the pedal stroke, the biggest problem of traditional crank rotation drive is solved, namely, the efficiency of rotation drive in the vicinity of the uppermost point PH (which is at least equivalent to the top dead center of a normal crank in terms of position) and its vicinity, as well as the lowermost point PL (which is at least equivalent to the bottom dead center of a normal crank in terms of position).

[0109] Furthermore, in devices where the action or pedaling is performed by the arms and legs of a person, appropriately adjusting the direction of the action (pedaling) maximizes the characteristics of this structure and expands its applications, making it particularly suitable for this structure. Moreover, by combining it with a suitable tilting mechanism—that is, mounting it at an offset angle from the viewpoint of the crankshaft CX1—this structure can be applied to a wide range of uses. On the other hand, this structure can also be effectively utilized in devices where the person is not driving.

[0110] Second Implementation Method Here, the second embodiment will be referred to as the present second embodiment. According to Figures 10-12 In addition to the structure of the first embodiment, the basic structural features of this second embodiment include an elastic support member, which is mainly used to form a support state and has a front end abutment portion, straddling the first slider S1 and the front block S21 of the second slider. Therefore, the basic structure and basic mode of operation are no different from the structure of the first embodiment corresponding to claim 1 of the present invention.

[0111] Furthermore, in this second embodiment, the lowest position of the pedal axle P10 is slightly lowered within the essentially vertically movable range of the human foot, while the highest position is also lowered by the same degree to control the height. Therefore, for the reason that the forward and backward range of the aforementioned pedal axle circular track can be increased, the rotation range of the crank rotation axis CX2a when the pedal P is pressed is set from the uppermost point PH to the lowermost point PL. Instead of centering on the fixed swing fulcrum axis AX, the crank axis CX1a is centered, and the basic line on one side of the fixed swing fulcrum axis A4 is offset from the horizontal position in the direction towards the uppermost point PH by an appropriate angle β. Without changing the relationship between this basic line and the overall structure, they are offset together, that is, they are installed with an offset angle β when viewed in the direction of the crank axis CX1.

[0112] However, even in this case, as described in the first embodiment, there is no component serving as an obstacle-holding interval between the first slider front end abutment portion S1f and the second slider front end abutment portion S2f. In such a structure, there is not a sufficient lever effect near the approximate uppermost point PH at the start of pedaling, the increase in the driving rotational torque around the crankshaft CX1 and the improvement in the efficiency of the rotational drive are insufficient, and in the trajectory of the axis PX during the return stroke once, the travel direction of the pedal P near the top dead center just before the pedaling action will change drastically.

[0113] The effect achieved in this second embodiment is to improve the abrupt change in the trajectory direction of the pedal axis PX. When pedaling begins, the pedal P is moved slightly towards the front end in a direction away from the fixed swing fulcrum axis AX of the first slider S1 and the swing arm A, thereby increasing the driving rotation torque around the crank shaft CX1 when the pedal P is pedaled and improving the rotational driving efficiency.

[0114] Based on the aforementioned second prerequisite, which is the characteristic structure requirement of the mechanism Z provided by this invention, the most ideal basic narrow angle and the crank circle diameter are set, and the length of the appropriate gap between the first slider S1 and the second slider front block S21 is set to be equal to the length of the long side dimension, thereby uniquely determining the necessary minimum length of the swing arm A. Next, by way of example, without changing the necessary minimum length of the swing arm A in actual application, by reducing the distance between the fixed swing fulcrum axis AX and the crank axis CX1a, the basic narrow angle with a certain degree of flexibility in setting is slightly increased. Conversely, if the distance between the first slider S1 and the second slider front block S21 when they are closest can be increased to set a space that is greater than or equal to the shortest contraction length of the elastic support member N used to form the support state, then it is of course possible to insert it onto the guide rod A3 within this space, keeping one end face of the elastic support member N which also serves as the shortest contraction length of the front end abutment part, so that the end face of either the first slider S1 or the second slider front block S21 has the function of supporting the abutment member Nt. In this case, there is no difference in the mode of operation, function, and effect as in the second embodiment. The second embodiment has the same concept of setting an elastic support member across the first slider S1 and the front block S21 of the second slider.

[0115] However, in this second embodiment described herein, it is not permissible to change the predetermined ideal basic narrow angle, and a space cannot be provided in the interval between the first slider S1 and the second slider front block S21 when they are closest to each other to insert the elastic support member N with the minimum contraction length. In this case, such as Figure 10 As shown, the elastic support component N is not located between the first slider S1 and the second slider front block S21, but is located at a staggered position on the first slider S1 or the second slider front block S21 at the lower part of the swing arm A, and the corresponding support abutment component Nt is installed on the second slider front block S21 or the first slider S1 respectively.

[0116] For example, such as Figure 10 As shown, an elastic support member N is provided on the first slider S1, with its front end serving as the front abutment part S1f of the first slider. A support abutment member Nt is provided on the front block S21 of the second slider, with its rear end serving as the front abutment part S2f of the second slider. In this case, the front abutment part S2f of the second slider and the rear abutment part S2r of the second slider located on the support abutment member Nt are held relative to each other on the swing arm A at a predetermined interval.

[0117] According to this structure, when the first slider S1 and the second slider front block S21 approach each other during the latter part of the return stroke, corresponding to the reduction in their intervals, the abutment portion S1f on the front end side of the first slider located in the elastic support member N and the abutment portion S2f on the front end side of the second slider located in the support abutment member Nt abut against each other, causing the elastic support member N to abut and retract. At this time, a thrust is transmitted from the first slider S1 to the second slider front block S21, causing the pedal P to move slightly towards the front end side of the swing arm A at the start of the pedal stroke. Therefore, compared with structures without the elastic support member N, the driving rotational torque caused by the leverage ratio effect near the uppermost point PH can be increased, thereby improving the rotational drive efficiency.

[0118] Additionally, while mitigating the abrupt change in the P-track direction of the pedal before the end of the recovery stroke, such as Figure 11 As shown, the specific motion trajectory of the pedal axis PX is formed as follows: it expands slightly towards the front end of the swing arm A, and the expansion degree at the rear end is approximately the radius of the crank circle used in the implementation. Overall, it is a smooth, roughly elliptical curve circle with a front-to-back amplitude close to the arm length of a normal crank, or with the front and back as the short axis and the top and bottom as the long axis, and is approximately symmetrical.

[0119] In this second embodiment, the elastic support member N consists of a compression coil spring N1, a spring retaining shaft N2 inserted into and holding the compression coil spring N1, and a support bearing member N4. The support bearing member N4 has a bearing hole N3 that supports the spring retaining shaft N2 so that it can slide along its long side. On the other hand, the support abutment member Nt abuts against the front end of the spring retaining shaft N2 and bears the force applied by the compression coil spring N1. The support abutment member Nt is mounted on the front block S21 of the second slider, and its rear end side in the long side direction becomes the front end abutment part S2f of the second slider.

[0120] The end of the spring retaining shaft N2 on the support abutment member Nt side is formed into a flange shape as an extension and top abutment of the compression coil spring N1, and also serves as the abutment part S1f on the front end side of the first slider. The opposite end is threaded, and the spring retaining shaft N2 is prevented from disengaging from the support bearing member N4 under the force of the compression coil spring N1 by a double locking nut N5, etc. In addition, the double locking nut N5 also serves to adjust the length of the spring retaining shaft N2 extending from the support bearing member N4.

[0121] This adjustment determines when the front end of the spring retaining shaft N2 abuts against the support abutment member Nt during the latter half of the return stroke of pedal P. Alternatively, the force of the compression coil spring N1 can be applied by abutting the front end of the spring retaining shaft N2 against the support abutment member Nt from the very beginning of the latter half of the return stroke of pedal P.

[0122] The compression helical spring N1, spring retaining shaft N2, support bearing component N4, and support abutment component Nt are respectively mounted on the first slider S1 and the second slider front block S21, located at the lower part of the swing arm A. At this time, a step portion N4a is provided on the support bearing component N4, so that even when the first slider S1 and the second slider front block S21 are in contact, a space is provided to keep the compression helical spring N1 in the contracted state.

[0123] As one embodiment of the compression helical spring N1, its length difference between the unloaded state and the compressed state is large. When the pedal P on the other side is pressed, causing the pedal P on this side to be in the second half of the return stroke, the spring retaining shaft N2 abuts against the support abutting member Nt provided on the front block S21 of the second slider on which the pedal P is mounted. At the same time, the compression helical spring N1 has the force to move the second slider S2 as far as possible toward the front end of the swing arm A.

[0124] The movement of the second slider S2 may begin slightly later than the movement of the first slider S1 it abuts, but the movement will occur as long as the compression coil spring N1 continues to transmit the force that causes the second slider S2 to move.

[0125] Furthermore, in this second embodiment, as described above, the pedal P is moved further forward of the swing arm A. Compared to a structure without an elastic support member N, when the rotation drive begins, if the second slider front block S21 has already moved forward by about half of the initial movement distance of the pedal (action) stroke, the pedal stroke continues to be performed by pressing the pedal P mounted on it.

[0126] Next, for example, in this case, when the foot performs a pedaling action on one side of the pedal P ( Figure 11 and Figure 12 (Points F to H in the diagram) Since the support state is not released, in the first half of the pedaling, the coil spring N1 is compressed additionally due to the initial moving resistance of the second slider front block S21 relative to the pedaling component force, and finally the moving propulsive force of the first slider S1 relative to the second slider front block S21 that stops abutting against the swing arm front block A1. This requires additional action force to counteract the reaction force.

[0127] In the latter half of the stroke, the contraction is fully released, the compressed coil spring N1 extends and returns to its original unloaded length, ending one extension / retraction cycle. However, the pedaling energy used for contraction during this cycle is essentially returned through the crank rotation involved in the latter half of the pedal stroke; therefore, no energy loss occurs in the crank action of mechanism Z.

[0128] On the other hand, if the crankshaft is not offset by a certain angle when viewed from the CX1 direction at the start of the pedaling (action) stroke, the following phenomenon may occur, depending on the pedaling direction, such as Figure 11 As shown, the narrow angle formed by the line passing through line segment AX-CX1a and the line passing through line segment AX-PH is the upward angle. Therefore, the pedaling force in the opposite direction causes the compression coil spring N1 to contract. At the same time, the second slider front block S21 and the pedal P instantly move backward on the swing arm A, and then immediately move towards the front end under the push of the first slider S1.

[0129] However, in this second embodiment, as Figure 11 As shown, the fixed swing fulcrum shaft A4 side, i.e. the rear end side, which passes through the extension line of the fixed swing fulcrum axis AX and the crank axis CX1a, is installed on the frame F, etc., tilted at an appropriate angle β from the horizontal direction towards the highest point with the crank axis CX1a as the center. Therefore, the instantaneous reverse return of the pedal P is basically eliminated.

[0130] In addition, in this structure, mounting the frame F with the rear end facing upward and the front end facing downward at an angle β has other effects. As mentioned above, the lowest position of the pedal shaft P10 being stepped on is slightly lowered within the vertical movement range of the human foot, while the highest position is lowered by the same degree to control the height, which can greatly reduce the load of repeated stepping operations.

[0131] Industrial availability The pedal shifting crank rotation drive mechanism of the present invention can be used not only in general bicycles, but also in recumbent bicycles, as well as in tricycles, fitness equipment, or labor-saving devices and apparatuses for the disabled or commercial use. In addition, it can be widely used in devices that alternately apply external force to a pair of left and right crank arms mounted on the crank shaft and have an output part that rotates integrally with the crank shaft.

[0132] Explanation of reference numerals in the attached figures 3…Swing support component; 5…Output section; A…Swing arm; A1…Swing arm front end block; A2…Swing arm rear end block; A3…Guide rod; A4…Fixed swing fulcrum shaft; AX…Fixed swing fulcrum axis; CA…Crank arm; CX1…Crank shaft; CX1a…Crank axis; CX2…Crank rotation shaft; CX2a…Crank rotation axis; F…Frame; N…Elastic support component; Nt…Support abutment component; P…Pedal; PH…Upper point; PL…Lower point; PX…Pedal axis; S1…First slider; S1f…First slider front end abutment part; S1r…First slider rear end abutment part; S2…Second slider; S2f…Second slider front end abutment part; S2r…Second slider rear end abutment part; S2l…Second slider front block; Z…Pedal shifting type crank rotation drive mechanism.

Claims

1. A pedal-shifting crank rotation drive mechanism, characterized in that, have: A pair of left and right crank arms are respectively fixed to the two ends of a crankshaft that can be rotatably mounted on a frame or the like, and have a 180-degree phase angle difference in motion and perform an action. A crank rotation shaft is disposed at the front end of each of the left and right pairs of crank arms; A pair of left and right swing arms, the pair of left and right swing arms are axially supported by a fixed swing fulcrum shaft, the fixed swing fulcrum shaft is fixedly arranged on the frame etc. at a position that is separated from the crank shaft and exceeds the length of the crank arm; A pair of left and right first sliders are rotatably supported on the crank rotation shaft and held on the swing arm. They can reciprocate along the long side of the swing arm. When the direction of the fixed swing fulcrum axis along the long side is taken as the rear end side and the opposite direction is taken as the front end side, the front end abutting part and the rear end abutting part of the first slider that move together along the long side are kept facing opposite directions. A pair of second sliders, one on the left and one on the right, are held on the swing arm and are capable of reciprocating along the long side of the swing arm. The front and rear abutment portions of the second sliders, which move integrally along the long side, are held facing each other at a predetermined interval. The second sliders reciprocate intermittently in the same direction and within a movable range, accompanying the reciprocating movement of the first sliders, through contact or non-contact between the opposing front and rear abutment portions of the first sliders, or contact or non-contact between the opposing rear abutment portions of the first and second sliders. A pair of left and right pedals are mounted on the front block of the second slider. The front block of the second slider is configured to be located on the front side of the swing arm, closer to the front end of the first slider, during the reciprocating movement of the first slider. The left and right pedals, through their alternating movements, cause the left and right swing arms to swing alternately. This swinging motion, in conjunction with the swinging motion, simultaneously applies rotational force to the crank arm via the first slider while drawing a deformed elliptical trajectory, and also applies rotational force to the crank shaft. The pedal-shifting crank rotation drive mechanism provides rotational output to the output section that rotates integrally with the crankshaft.

2. The pedal-shifting crank rotation drive mechanism according to claim 1, characterized in that, have: An elastic support member, which retracts in response to a decrease in the distance between the first slider and the front block of the second slider, and simultaneously transmits a force that causes the second slider to move towards its front end within a movable range in the long-side direction, having a front-end abutment portion held at either the first slider or the second slider; and... A supporting abutment member having a front end abutment portion held at either the second slider or the first slider.

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