Pedal shift type crank rotary drive mechanism

Abstract

To provide a pedal shift type crank rotary drive mechanism that can be used a long period of time without requiring large leg strength.SOLUTION: A pedal shift type crank rotary drive mechanism Z includes: a pair of left and right crank arms CA and a crank rotating shaft CX2 that are fixed to a crank shaft CX1 pivotally supported on a frame F or the like; a pair of left and right swing arms A pivotally supported on a fixed swing fulcrum axis A4 located away from the crank shaft CX1; a first slider S1 pivotally supported on the crank rotating shaft CX2 and reciprocable along a longitudinal direction of the swing arm A; a second slider S2 abutting or not abutting the first slider S1 and intermittently reciprocable; and a pedal P attached to a second slider front block S21 and allowing the swing arm A to swing and rotating the crank shaft CX1 while tracing a substantially oval trajectory. The pedal shift type rotary drive mechanism provides a rotation output to an output part 5.SELECTED DRAWING: Figure 1

Description

[Technical Field]

[0001] The present invention relates to a pedal-shift crank rotation drive mechanism that includes 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 section that rotates integrally with the crankshaft. [Background technology]

[0002] Conventionally, a crank rotation drive system of this kind is disclosed in, for example, Patent Document 1 (see

[0011] to

[0021] , FIGS. 1 and 2).

[0003] This system comprises a pedal shaft 10 that is fixed to the frame 3 and does not rotate itself, guide members 11a and 11b that rotate within a certain angle around the pedal shaft, and rotatable pedals 12a and 12b that are attached to the guide members 11a and 11b and move up and down reciprocally.

[0004] Guide grooves 13a and 13b are formed on the insides of the guide members 11a and 11b, respectively, and protruding members 26a and 26b formed integrally with the crank cams 22a and 22b are received in the guide grooves. The crank cams 22a and 22b are integrally assembled to a crankshaft 20, and a gear 21 is also integrally assembled to the crankshaft.

[0005] When the pedals 12a, 12b move up and down, the protruding members 26a, 26b rotate along the guide grooves 13a, 13b, and at the same time, the crank cams 22a, 22b, the crank shaft 20, and the gear 21 rotate. When the gear 21 rotates, the gear 31 meshed with it rotates in the opposite direction, and the chain gear 32 formed integrally with the gear 31 also rotates together.

[0006] The fixed shaft 30 is assembled and fixed to the frame 3 and does not rotate, and only the gear 31 and the chain gear 32 rotate. Therefore, the gear 31 and the chain gear 32 are assembled to the fixed shaft 30 via bearings.

[0007] This device operates smoothly when, when one pedal 12a is at the top dead center and the other pedal 12b is at the bottom dead center, the protruding members 26a and 26b of the crank cams 22a and 22b are inclined at a certain angle θ3 in the direction of rotation past the vertical center line of the crankshaft 20.

[0008] This configuration can be applied to saddleless bicycles that move forward by pedaling up and down. The pedals operate smoothly, and the up and down movement of the pedals is easily converted into rotational movement. Furthermore, by riding while standing, the user can get a full-body workout compared to riding a bicycle while sitting. [Prior art documents] [Patent documents]

[0009] [Patent Document 1] Special Publication No. 2010-508191 Summary of the Invention [Problem to be solved by the invention]

[0010] However, in the conventional crank rotation drive system described above, when the pedals are raised and lowered, the movement locus is a circular arc shape that repeatedly moves up and down, with the same locus centered on the pedal shaft 10. This results in unnatural leg movements of the user that differ from the bending and stretching of the legs when a person walks, making it difficult to fully exert leg strength and making the legs prone to fatigue, making it difficult to use for long periods of time.

[0011] As described above, although the conventional crank rotation drive system has a simple overall structure, such as a fixed pedal shaft 10, there are still issues to be resolved regarding the convenience of the device, etc. Therefore, there has been a demand in this technical field for a crank rotation drive system or mechanism that does not require a great deal of leg strength and can be used for long periods of time. [Means for solving the problem]

[0012] (Features and configuration) The pedal shift type crank rotation drive mechanism according to the present invention has the following characteristic configuration: a pair of left and right crank arms fixed to both ends of a crankshaft rotatably attached to a frame or the like, and operating with an operating phase angle difference of 180 degrees; a crank rotation shaft provided at the tip of each of the pair of left and right crank arms; a pair of left and right swing arms pivotally supported on a fixed swing fulcrum shaft fixedly disposed at a position away from the crankshaft by a distance greater than the length of the crank arm in the frame or the like; a pair of left and right first sliders that are rotatably supported on the crank rotating shaft and held by the swing arm, and are reciprocally movable along the longitudinal direction of the swing arm, and in which a first slider front end side abutment portion and a first slider rear end side abutment portion are held facing in opposite directions and move integrally in the longitudinal direction when the direction of a fixed swing fulcrum axis in the longitudinal direction is the rear end side and the opposite direction is the front end side; a pair of second sliders, held by the swing arm and reciprocating along the longitudinal direction of the swing arm, wherein a second slider front end contact portion and a second slider rear end contact portion, which move integrally in the longitudinal direction, are held facing each other with the first slider sandwiched between them at a predetermined interval, and the pair of left and right second sliders intermittently reciprocate within a movable range in the same direction as the reciprocating movement of the first slider due to contact or non-contact between the opposing first slider front end contact portion and the second slider front end contact portion, or contact or non-contact between the opposing first slider rear end contact portion and the second slider rear end contact portion; a pair of left and right pedals attached to a second slider front block configured to be located on the tip side of the first slider of the swing arm during the reciprocating movement of the first slider, and which alternately swing the left and right swing arms by alternate operation of the second slider front block, and which, in combination with the swinging, apply a rotational force to the crank arm via the first slider while tracing a modified elliptical locus, and simultaneously apply a rotational force to the crank shaft; The point is to provide a rotational output to an output section that rotates integrally with the crankshaft.

[0013] (effect) In this pedal-shift crank rotation drive mechanism, a first slider is rotatably supported on a crank rotation shaft provided at the tip of a pair of left and right crank arms, and the first slider is held movably in the longitudinal direction by a swing arm that swings back and forth. The first slider has a first slider front-end contact portion and a first slider rear-end contact portion that move integrally with the first slider and face in opposite directions.

[0014] A pair of left and right swing arms are each provided with a second slider. The second slider has a second slider front end contact portion and a second slider rear end contact portion that move integrally and are held facing each other while sandwiching the first slider at a predetermined interval. As the first slider moves back and forth, the first slider front end contact portion and the second slider front end contact portion, or the first slider rear end contact portion and the second slider rear end contact portion, which are provided in a facing state in the same direction, abut against each other. Also The second slider moves back and forth intermittently within its movable range due to non-contact. The movement range is smaller than that of the first slider due to the amount of interruption in the movement.

[0015] The pair of left and right second sliders has a second slider front block located on the tip side of the first slider of the swing arm during the reciprocating movement of the first slider, and the left and right swing arms are alternately swung by the alternating operation of the pair of left and right pedals attached to the second slider front block, which applies a rotational force to the crankshaft, and the trajectory of the pedal axis, in combination with the swing of the swing arm, Overall, before and after It is configured to trace a circular locus that is a deformed ellipse with a top-bottom long axis that bulges out on the short axis side beyond the length of the crank arm.

[0016] in this case, Swing armThe front end face of the first slider in the longitudinal direction may be the first slider front end contact portion, and the rear end face may be the first slider rear end contact portion.Also, the rear end face of the second slider front block may be the second slider front end contact portion.

[0017] The reciprocating distance of the first slider is the crank circle diameter traced by the rotational path of the crank pivot axis. In this proposal, a crank having a pair of crank arms and a crank pivot axis of a predetermined length is used. Here, this is referred to as the practical crank, and the rotational path of the crank pivot axis is referred to as the practical crank circle. The second slider front block to which the pedal is attached is located closer to the tip of the swing arm than the first slider, and while the first slider moves back and forth on the swing arm in response to the operation of the pedal from start to finish, the second slider front block approaches the tip block of the swing arm until they come into contact.

[0018] When the swing arm swings, only when the first slider front-end abutment portion or the first slider rear-end abutment portion of the first slider abuts against the second slider front-end abutment portion or the second slider rear-end abutment portion, the second slider moves in the same longitudinal direction in conjunction with the first slider. A pedal is provided on the second slider front block, which is located closer to the swing arm front end than the first slider, and input is transmitted via the pedal to the swing arm, first slider, crank pivot shaft, and crank arm.

[0019] With this configuration, the left and right swing arms continuously swing back and forth through a predetermined angle in response to the alternating operation of the pair of left and right pedals, causing the first slider to continuously move back and forth in conjunction with the operating force, and the crank arm to continuously rotate, thereby continuously rotating the crankshaft and generating a rotational output. At that time, the second slider intermittently moves back and forth in the same direction as the movement of the first slider in the longitudinal direction of the swing arm, due to the abutment and non-abutment between its two abutment portions and the abutment portions of the first slider.

[0020] While the pair of left and right oscillating arms are swinging back and forth, the pair of left and right pedals attached to the second slider front block can also move back and forth along the longitudinal direction of the oscillating arms, making it possible to change the distance from the fixed oscillating fulcrum axis, which is the oscillating fulcrum of the oscillating arms, to the pedals.

[0021] Furthermore, the pedal shift type crank rotation drive mechanism of this configuration is basically configured such that the direction of the base line connecting the fixed swing fulcrum axis and the crank axis is horizontal, and will be mainly described in this form hereinafter. However, depending on the embodiment and usage situation to be used, the base line can be swung around the crank axis or the fixed swing fulcrum axis by an appropriate predetermined angle above or below the horizontal, including horizontal, without changing the correlation of the entire configuration. In other words, the angle is changed when viewed from the crankshaft direction. It can be fitted and used to provide a wider range of applications.

[0022] Now, if we consider the direction of the base line connecting the fixed pivot axis and the crank axis to be horizontal, the top and bottom dead centers of the crank pivot shaft in this configuration are the points of contact between the upper and lower tangents drawn from the fixed pivot axis to the actual crank circle and the actual crank circle. The highest point on the actual crank circle is the topmost point, and the lowest point is the bottommost point. The topmost point is the point where the crank circle has definitely passed top dead center, and the bottommost point is the point where the crank circle has not yet reached bottom dead center. Therefore, the range in which the crank arm can be swung by actuating one pedal to rotate the crank arm is basically from the point where the crank pivot axis has passed top dead center on the actual crank circle, where no pedal force component that rotates the crank arm is generated, to bottom dead center.

[0023] Furthermore, because the pair of left and right crank arms have an operating phase angle difference of 180 degrees, in this case, pedal actuation rotates the crank arms a half rotation of 180 degrees, so generally, the crank pivot axis on the pedal actuating side is operated until it reaches bottom dead center, as in conventional crank actuation, to complete the pedal actuation stroke. At this time, the rotation start point of the crank pivot axis corresponding to the start point of actuation is a point symmetrical to the phase angle difference position 180 degrees back from bottom dead center on the actual crank circle around the crank axis center, that is, a point symmetrical to top dead center across the reference line connecting the highest and lowest points on the circle, and therefore the pedal actuation position corresponding to this point is the pedal actuation start point.

[0024] However, in this configuration, the rotation range of the crank rotation axis when each pedal is operated is determined by appropriately setting a predetermined distance between the abutment portions on the front and rear ends of the second sliders held in directions facing each other on the second sliders. In other words, the rotation range of the crank rotation axis when the pedal is operated can be from a point symmetrical to the top dead center to the bottom dead center, or from the highest point (or its vicinity) to the lowest point (or its vicinity), although both are possible, and is set as a design specification.

[0025] If the rotation range of the crank pivot axis when the pedals are operated is defined as from the highest point to the lowest point (hereinafter referred to as "this case"), when one pedal is operated, the opposing crank pivot axis is at the rotation start point, and when the other pedal performs its operation stroke (hereinafter referred to as the operation stroke), the one crank pivot axis performs a passive rotation from the lowest point in the crank circle to the rotation start point, i.e., the highest point (hereinafter referred to as the return stroke). One cycle of the crank pivot axis locus, combining the operation stroke and return stroke of each pedal, is from the highest point to the highest point, or from the lowest point to the lowest point when taken from the start of the return stroke.

[0026] As a result, for example, the rotation direction of the crank rotation axis during the actuation stroke for actuating one pedal is set to a direction from the top of the rotation start point to the bottom of the actuation stroke, passing through the midpoint of the actuation stroke where the longitudinal direction of the crank arm and oscillating arm is aligned with the line connecting the fixed oscillating fulcrum axis and the crank axis. Naturally, the crank shaft also rotates in the same direction. If the first-slider-side end face of the second slider front block is the second slider tip-side abutment point, during the first stage of rotation in which the longitudinal direction of the crank arm and oscillating arm moves from the actuation start point to the midpoint, the pedal is attached to the second slider front block, whose second slider tip-side abutment point is already in a state of abutting against the first slider tip-side abutment point at the actuation start point, as described below, and is maintained at the tip of the oscillating arm.

[0027] Then, in this state, the pedal is operated to rotate the swing arm, which moves the first slider via the crank pivot shaft and moves the entire second slider until it abuts against the swing arm's tip block, which is the end of the swing arm's range of movement.

[0028] When the pedal is actuated in this way in the first stage of rotation of the operating stroke, the pedal shaft, in conjunction with the swing of the swing arm, traces a curved locus that bulges downward toward the tip.

[0029] During the remaining second half of the crank arm's rotational stroke, only the first slider moves toward the fixed pivot axis until the crank pivot axis reaches its lowest point, following the crank circle path. However, the pedal attached to the second slider front block ends its operation stroke in contact with the pivot block due to the opposing directions of the actuating forces. As a result, the pedal axis, coupled with the swing of the swing arm, traces a partial arc with a radius equal to the distance from the fixed pivot axis to the pedal axis. At this time, the rear end contact point of the first slider, i.e., the rear end face, approaches the rear end contact point of the second slider without coming into contact with the rear end contact point of the second slider until the axis of the crank pivot shaft supporting the first slider reaches its lowest point. This is the first prerequisite, which is an important requirement in this case, that the rear end contact portion of the first slider does not contact the rear end contact portion of the second slider until the rotation axis of one of the cranks reaches its lowest point.

[0030] In this case, however, even if one of the pedals is further operated, the rear-end contact portion of the first slider on that side will soon come into contact with the rear-end contact portion of the second slider, preventing operation due to the opposing force toward the rear end caused by the crank rotating force acting on the first slider and the forward operating force acting on the second slider, and the distance between the forward-end contact portion of the second slider and the rear-end contact portion of the second slider is set so that the axis of the crank rotating shaft that pivotally supports the first slider ends its operating stroke without moving significantly beyond its lowest point. It is not until the other pedal is subsequently operated that the return stroke of one of the crank rotating shafts begins, and with the rear-end contact portion of the first slider on that side coming into contact with the rear-end contact portion of the second slider, both begin moving toward the rear end of the swing arm.

[0031] The longitudinal travel of the first slider, which is appropriately determined based on these configuration requirements, the user, and the conditions of use, the corresponding distance between the leading end and trailing end of the second slider, the lengths of the first and second sliders, the required lengths of other components, and appropriate and necessary clearances, are also determined as design specifications to minimize the length necessary to achieve compactness. For example, compared to conventional crank rotation drive mechanisms used in bicycles, a pedal-shift crank rotation drive mechanism with an oscillating arm like this one tends to be longer in the longitudinal direction, posing fundamental problems such as interference between the operating leg and the front wheel of the bicycle. To prevent this, the second prerequisite of this important requirement is to keep the oscillating arm as long as possible.

[0032] Here, when stepping on the pedal with your legs as in a bicycle, for example, a pair of left and right crank arms and a crank rotation shaft are implemented on the crank circle. lowest point The stroke up to the pedal depression end point corresponding to the pedal is the depression stroke, and the stroke from the depression end point to the pedal start point is the return stroke before the depression stroke. The return stroke is performed by the depression strokes on the opposite sides.

[0033] During the return stroke, when one pedal rotates the crank arm upward from its lowest point on the crank circle (the end point of the pedal stroke in the practical application) to a line passing through the fixed swing fulcrum axis and the crank axis, the rear end of the first slider on the swing arm abuts against the rear end of the second slider, and the entire second slider moves toward the fixed swing fulcrum axis without abutting against the rear block on the fixed swing fulcrum axis side of the swing arm. Accordingly, the pedal attached to the front block of the second slider also moves the same distance toward the fixed swing fulcrum axis. As a result, as described below, the pedal axis, in conjunction with the swing of the swing arm, describes an arc of approximately a quarter-length modified ellipse that bulges outward toward the rear end of the base line by approximately the radius of the practical crank circle. In this case, the longitudinal direction of the crank arm and the swing arm also coincides with the direction of a line passing through the axis of the swing arm fixed swing fulcrum and the axis of the crank.

[0034] In the latter part of the return stroke, when the crank arm continues to rotate to the highest point, only the first slider moves toward the tip of the swing arm according to the trajectory of the crank circle employed, and ideally the tip abutment portion of the first slider, i.e., the tip end face, comes closest to the tip abutment portion of the second slider front block, i.e., the rear end face, without coming into contact with it, thus completing the return stroke.

[0035] During this time, that is, in the latter part of the return stroke, the second slider remains stopped in the longitudinal direction of the swing arm, and therefore, in conjunction with the swing of the swing arm, the pedal axis of the pedal attached to the front block of the second slider describes a partial arc curved locus pointing upward toward the rear end, with the radius being the distance from the fixed swing fulcrum axis to the pedal axis.

[0036] However, in this case, by setting the length of the swing arm, which is the second prerequisite, to the minimum possible length, the leading end face of the first slider and the rear end face of the second slider front block, to which the pedal is attached, which has been swinging in an upward, partially arcuate trajectory, will come into contact not at the transition between strokes but at approximately top dead center, just before the crank pivot axis reaches its uppermost point, in other words, the top dead center, in the latter part of the return stroke, causing a sudden change in direction in the trajectory of the pedal axis, resulting in an uneven spot. While this is not desirable for pedal movement, it provides a good opportunity to time the subsequent pedal depression during use.

[0037] In this case, one way to prevent this contact would be to increase the distance between the contact portion at the front end of the second slider and the contact portion at the rear end of the second slider, and to increase the length of the swing arm by at least that amount, but this contradicts the second prerequisite.

[0038] From the results above, if the rotation range of the crank pivot axis when the pedal is operated is from the highest point to the lowest point, the operating trajectory of the pedal axis after one cycle has completed will have points where the direction changes suddenly, but in combination with the swing of the oscillating arm, it will bulge downward and forward of the oscillating arm, and will bulge by an amount equivalent to the displacement distance in the base line direction corresponding to the amount of movement of the axis of the crank pivot axis on which the first slider is journalled towards the rear end after the lowest point of the return stroke, in other words, it will bulge by approximately the radius of the crank circle used in the embodiment, and overall will describe a deformed oval circle with a larger vertical diameter and a larger front-to-back width on the short diameter side that is more accommodating to the folding and pushing movements of a person's legs, which is not found in conventional fixed fulcrum oscillating arm crank rotation drive systems such as those shown in Patent Document 1.

[0039] Regarding the first precondition, if, at the end of the depression stroke of one pedal, the abutment portion on the rear end of the first slider, i.e., the rear end face, abuts against the abutment portion on the rear end of the second slider before the axis of the crank rotating shaft on which the first slider is journalled reaches the lowest point on the actually employed crank circle, the force towards the rear end due to the crank rotating force acting on the first slider and the operating force towards the front end acting on the second slider will be opposed to each other, preventing the crank from rotating, and the crank rotating shaft on the opposite side will not reach the operating start point of the crank rotating shaft on the actually employed crank circle, i.e., the highest point, and the operating force due to subsequent pedal depression (operation) will be insufficient, which will affect the crank rotation, so this is highly important.

[0040] Therefore, taking everything into consideration, the basic idea here is to satisfy the design specifications of the first and second prerequisites.

[0041] Here, in light of the first and second prerequisites, we will explain basic matters such as (1) the minimum length of the oscillating arm, (2) the movement width of the first slider, and (3) the corresponding setting of the distance between the abutment portion on the tip end side of the second slider and the abutment portion on the rear end side of the second slider.

[0042] (1) First, to minimize the necessary length of the swing arm, the narrow angle (referred to as 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 fixed swing fulcrum axis and the highest point on the practically employed crank circle, and the practically employed crank circle diameter are set. When the crank rotation axis is at the farthest position on the practically employed crank circle, that is, when it is at the intersection of the extension line connecting the practically employed crank circle and the fixed swing fulcrum axis and the crank axis, the length of the swing arm is set to the minimum necessary length when the second slider front block is positioned with an appropriate gap on the tip side of the first slider pivotally supported on the crank rotation shaft, and the swing arm tip block is further positioned with an appropriate gap on the tip side of that.

[0043] Therefore, basically, the length of the oscillating arm from the fixed oscillating fulcrum axis to the tip side is the sum of 1) the distance from the fixed oscillating fulcrum axis to the crank axis, 2) the length of the crank arm, i.e., the distance between the crank axis and the crank rotation axis, 3) the width from the crank rotation axis of the first slider to the side surface at the tip side, 4) the width of the second slider front block, 5) the width of the oscillating arm tip block, and 6) the total of appropriate gaps between the other element parts.

[0044] However, if the width of the second slider front block is increased and the pedal is attached closer to the tip to give the swing arm a greater leverage, the swing arm length will also be increased accordingly. The basic narrow angle is the same narrow angle formed by the lines connecting the highest and lowest points with the fixed swing fulcrum axis and the base line. Taking into account the length of the swing arm, the size of the component parts, the depression position, height, stroke, etc., the basic narrow angle is preferably between 20 degrees and 35 degrees, but a value between 25 degrees and 30 degrees is most effective.

[0045] (2) The total travel of the first slider in the longitudinal direction of the swing arm is twice the length of the crank arm, i.e., twice the distance between the crank axis and the crank rotation axis, which is the crank circle diameter.

[0046] (3) Next, for example, with regard to the distance between the contact portion at the front end of the second slider and the contact portion at the rear end of the second slider when the rotation range of the crank pivot axis when the pedal is depressed (activated) is from the highest point to the lowest point, if the swing arm is to be made the minimum necessary length in light of the second condition, in addition to the first precondition that when one crank pivot axis reaches the lowest point at the end of the depression stroke in the crank circle used in the embodiment, the rear end face that is the contact portion at the rear end of the first slider on that side will not contact the contact portion at the rear end of the second slider, even if the pedal is continued to be activated, the contact portion at the rear end of the second slider on that side will immediately contact the contact portion at the rear end of the second slider. This means that the contact portion at the rear end of the second slider will be positioned further rearward of the first slider, separated by the minimum necessary gap.

[0047] On the other hand, at this time, the second slider front block is pressed against the swing arm tip block by pressing down on the pedal attached to it, so the set distance in this case is the distance between the contact point on the tip side of the second slider and the contact point on the rear end side of the second slider.

[0048] Therefore, if the rotation range of the crank rotation axis when the pedal is depressed is from the highest point to the lowest point, the distance between the abutment portion on the tip side of the second slider and the abutment portion on the rear side of the second slider on the oscillation arm, which is kept to the minimum necessary length, is the longitudinal movement distance of the oscillation arm when the crank rotation axis on which the first slider is pivotally supported moves from the point farthest from the fixed oscillation fulcrum axis to the lowest point, and therefore is the sum of the longitudinal width of the first slider and the movement distance of the first slider in the latter part of the depression (actuation) stroke (excluding the minimum necessary gap).This results in the mechanism of this configuration, which ensures that the first slider does not move significantly beyond the lowest point during the depression (actuation) stroke that starts from the highest point and ends at approximately the lowest point.

[0049] Incidentally, if the rotation range of the crank pivot axis when the pedal is depressed is set from the point symmetrical to top dead center to bottom dead center, then it is necessary to widen the gap between the contact point on the tip side of the second slider and the contact point on the rear side of the second slider by the distance that the first slider moves in the longitudinal direction of the swing arm when the crank pivot axis rotates an additional amount from the lowest point to bottom dead center in the crank circle implemented in the latter part of the depression (operation) stroke.

[0050] With this configuration, as shown in Figure 8, the pedal slides toward the tip along the swing arm during the pedal depression stroke, and slides toward the fixed rotation axis along the swing arm during the first part of the pedal return stroke. This causes the pedal axis to trace a trajectory of a deformed elliptical circle with a large front-to-back width, a short front-to-back axis, and a long vertical axis.

[0051] However, although the distance traveled toward the rear end during the first stage of the return stroke and the bulge in the fore-and-aft width along the base line of the pedal axle circle locus are proportional to each other, they are not the same length. The bulge in the pedal axle width is primarily determined by the displacement of the pivot axis toward the base line when it pivots toward the rear end on the actual crank circle, and the maximum value of this displacement is the bulge in the same direction. Therefore, if the minimum required gap is assumed to be infinitesimal, the bulge in the fore-and-aft width of the pedal axle circle locus, which is the same as the bulge in the fore-and-aft width of the pivot axis toward the rear end, will naturally be approximately the radius of the actual crank circle.

[0052] Therefore, the pedal axis circle for one cycle including the depression stroke trajectory Therefore, by appropriately setting the crank circle diameter for the practical application relative to the comparative crank circle diameter described later, it is possible to make the overall fore-aft width of the bulge of the pedal axle circle path approximately the radius of a conventional normal crank circle, i.e., the normal crank arm length.

[0053] Incidentally, if the depression stroke as described above is from the line-symmetrical point of top dead center to the bottom dead center on the crank circle in the practical application, and the return stroke is from the line-symmetrical point of bottom dead center to the line-symmetrical point of top dead center, the travel distance of the first slider in the early part of the return stroke, which mainly determines the longitudinal width of the corresponding pedal axle circle path, will be shorter than the travel distance when the depression stroke is from the highest point to the lowest point and the return stroke is from the lowest point to the highest point, as in this configuration. This is also clear from the fact that in Figure 6, the bottom dead center is closer to the point on the crank circle in the practical application that is closest to the fixed swing fulcrum axis of the crank rotation axis than the lowest point.

[0054] Therefore, in this configuration, starting from the lowest point on the crank circle implemented in the early stage of the return stroke, when the movement of the first slider brings the second slider to which the pedal is attached closest to the fixed swing fulcrum axis on the swing arm, the bulge in the front and rear on the short diameter side of the pedal shaft center trajectory is increased.

[0055] As a result of the above, in this configuration, the pedal axis, in conjunction with the swing of the swing arm, has a slight bulge at the tip end of the swing arm, and when combined with the rear end, the pedal axis bulges forward and backward by more than the radius of the crank circle actually used, or roughly the normal length of the crank arm, tracing a deformed oval circle trajectory with a large front-to-back width, a short diameter front-to-back, and a long diameter up and down, which is not found in conventional fixed fulcrum swing arm crank rotation drive systems.

[0056] The pedal itself moves vertically and longitudinally due to the swing of the swing arm, and as a result, the effect of this configuration is that, for example, when using the swing arm to step on the pedal with the foot and rotate the crank arm, the pedal moves in a circular orbit that is easily adapted to the folding and pushing movements of the human leg, making it possible to pedal along a rotational trajectory that reduces fatigue in the user's legs. This is the first effect of this configuration.

[0057] Next, the mechanism of rotational drive of this configuration is such that, of the left and right pedals, the first slider held by the crank arm near the highest point of the crank circle in the embodiment and held by the swing arm moves along a trajectory in the longitudinal direction of the swing arm when, for example, a pedal attached to the second slider front block held by the swing arm is pressed down, and the second slider front block, which is located further towards the tip of the first slider and abuts it, and the pedal move together to the tip of the swing arm while maintaining the increased driving rotation moment due to a slight leverage effect, and the crank arm rotates around the crank shaft.

[0058] The pedal attached to the front block of the second slider moves to the end of its range of movement in the first stage of rotation until the crank arm is in the same direction as the line connecting the fixed swing fulcrum axis and the crank axis from the start of operation, and remains at the end of the swing arm in the remaining second stage of rotation of the depression (operation) stroke, which is the first half of the crank arm's rotation, and the crank rotating shaft is depressed to the lowest point of the actual crank circle, thereby increasing the driving rotational moment around the crank shaft due to the large leverage effect of the swing arm.

[0059] Furthermore, with this configuration, pedal depression begins at the start of operation of the crank rotation axis, that is, from the highest point on the practical circle that completely passes over top dead center and avoids it, and depression ends in the range up to the lowest point. However, overall, due to the large leverage of the oscillating arm that occurs particularly in the remaining latter stages of rotation of the depression (operation) stroke, the greatest problem with conventional crank rotation drives is that the pedal operation locus is a deformed ellipse with a large vertical long diameter and a large front-to-back width, including at least the highest point which is normally equivalent to top dead center of the crank in terms of position, and in its vicinity, and at least the lowest point which is normally equivalent to bottom dead center of the crank in terms of position, and in its vicinity, while also improving the efficiency of the rotation drive by combining the effect of the depression operation force component.

[0060] Therefore, compared to conventional fixed fulcrum swing arm crank rotation drive systems that do not have the roughly elliptical operating locus of pedals with a large front-to-rear width, the load on the user when operating the crank shaft using leg strength can be greatly reduced overall, which is the second effect of this configuration.

[0061] As described above, the leverage ratio of a swing-arm pedal shift-type rotary drive mechanism such as that of the present configuration increases the closer it is to the highest or lowest point, which normally corresponds to the top dead center or bottom dead center of a crank, and the drive rotational moment also increases due to this leverage action, so in combination with the pedal depression operating force, it is a rational means well suited to increasing the rotational moment near the highest or lowest point, which normally corresponds to the so-called top dead center or bottom dead center of a crank.

[0062] Furthermore, when this configuration is actually used on a bicycle, rotation is relatively easy by manipulating the direction of the ankle and naturally moving the leg forward with the joints of the lower limbs as the fulcrum, just like stepping on the crank of a normal bicycle, and once the crank arm rotates and the inertial force acts on the running body, continuous rotation is also easy, so the first and second effects can be enjoyed for a long period of time. Upbound The pedal shift type rotary drive mechanism of this configuration is particularly effective when riding a bicycle on slopes or other places where inertial force is not desirable.

[0063] In this way, when the direction of operation (stepping) is appropriately adjusted for an object that is operated or stepped on by a person's arms or legs, the features of this configuration can be maximized, leading to more uses and being advantageous for this configuration. Install it at an angle when viewed from the crankshaft direction. On the other hand, even for objects that do not rely on the movement of a human arm or leg, this configuration can be applied to a wider range of uses by effectively combining the above. , and installed at an angle when viewed in the crankshaft direction. can be combined to similarly apply to many applications.

[0064] (Features and configuration) In the pedal shift type crank rotation drive mechanism according to the present invention, a tension swing cam having a contact portion on the tip end side of the second slider, the tension cam being pivotally supported so as to be able to swing on a swing fulcrum shaft inserted into a bearing portion in a swing fulcrum bearing base attached to each of the second sliders held by the swing arm; a biasing spring attached to the swing fulcrum bearing base for swinging and rotating the tension swing cam in a predetermined direction; a cam positioning stopper provided on the second slider or the swing fulcrum bearing base for setting an upper limit position when the tension swing cam swings in the biasing direction of the biasing spring; a first cam roller having a contact portion on the tip side of the first slider attached and held by the first slider, for forming or releasing a tensioned state by contacting or not contacting the tension swing cam so that a predetermined distance maintaining state can be formed or released between the first slider and the second slider front block; The tip block of the swing arm can be provided with a cam swing / locking portion integrally attached with a second cam roller that serves as a swing abutment and a swing lock for the tension swing cam so that it can be moved and adjusted in the longitudinal direction, and a cam lock pin for swing locking.

[0065] (effect) The first slider and the second slider attached to the pair of left and right swing arms each have two contact points for the pedal operation. Of these, a first cam roller having the first slider tip contact point on its surface is attached to the first slider, and a tension swing cam having a second slider tip contact point is provided on the second slider to form a tensioned state by fitting into and contacting the first cam roller.

[0066] In this case, the contact surfaces of the second slider front end contact portion and the second slider rear end contact portion, which are located on the rear end side of the tension swing cam in the longitudinal direction, face each other and sandwich the first slider with a predetermined gap between them. Then, operate one of the left and right pedals attached to the second slider front block to start the operating stroke.

[0067] Also in this configuration, for reasons to be described later, it is desirable that the operating stroke be, for example, from the highest point to the lowest point, and the return stroke be from the lowest point to the highest point.

[0068] The main reasons for this are: By doing so, in this configuration Crank rotation axis on the crank circle is back At the beginning of the process lowest point It moves from the point closest to the fixed pivot axis, that is, until it reaches the line connecting the fixed pivot axis and the crank axis. When Pedal shaft circle The front-to-back width of the trajectory, In the case of the operating stroke from the line symmetric point of the top dead center to the bottom dead center The front-to-back width at the beginning of the return stroke from the bottom dead center of the crank rotation axis to the position closest to the fixed swing fulcrum axis It can be made larger and can be made easier to accommodate the folding and sending out movements of the legs, especially when stepping on them with a human leg.

[0069] If the rotation range of the crank pivot shaft when the pedals are operated is assumed to be from the highest point to the lowest point, when one pedal is operated to start the operating stroke, a rotational moment that rotates the crank pivot shaft is generated by a component of the pedal actuation force, causing the other pivot arm to pivot due to pedal operation, and just before one of the crank pivot shafts rotates and reaches its highest point, the tension pivot cam, which is in tension abutment with the first cam roller due to the biasing force of the biasing spring and the cam positioning stopper, will swing as a whole while the tip end of the side opposite the abutment moves into contact with the second cam roller. As a result, the tension pivot cam assumes a contact release position in which it is released from contact with the first cam roller, and at the same time, the tip end of the cam opposite the abutment side is engaged with the cam swing engagement portion provided on the swing arm and held in position.

[0070] For this reason, the shape of the tension swing cam when viewed from the side of the swing arm is such that the side that abuts against the first cam roller is the abutment portion at the tip of the second slider, and has a radius R centered on the swing fulcrum axis of the tension swing cam so that abutment and release can be performed smoothly, and the shape of the opposite side when viewed from the same direction has an inclined cut-shaped portion and a tip claw-shaped portion to allow swing abutment and swing locking between the second cam roller and the cam lock pin.

[0071] Then, during the operating stroke from one uppermost point to the lowermost point, the tension swing cam remains in the abutment release position, and only the first slider moves back and forth toward the tip of the swing arm, leaving a small gap with the tip block of the swing arm, thereby completing the operating stroke. At the end of this stroke, the rear end abutment portion of the first slider, i.e., the rear end face of the first slider, comes closest to the rear end abutment portion of the second slider without coming into contact with it, so that the length of the first slider in the longitudinal direction, the length of the tension swing cam from the swing fulcrum axis to the rear end side, the length of the second slider from the swing fulcrum axis to the tip side of the second slider abutment portion, the minimum required gap, etc. are appropriately set in accordance with the movement width of the first slider.

[0072] One pedal and the second slider are held in position at the tip of the swing arm while maintaining a predetermined distance from the fixed swing fulcrum axis, and in conjunction with the swing of the swing arm, the axis of one pedal traces an arc-shaped curved trajectory.

[0073] At this time, in the first half of the return stroke in which the other crank rotating shaft rotates from the lowest point of the employed crank circle to the highest point in response to the operation of one pedal, the minimum required gap is eliminated as soon as the rotation begins, and the other first slider abuts against the abutment portion on the rear end of the other second slider, following the entire second slider and pushing back the other pedal attached to the front block along the swing arm toward the rear end, i.e., toward the axis of the fixed swing fulcrum, by the radius of the employed crank circle, and meanwhile the other tension swing cam is swung by the spring 4 until it abuts against the cam positioning stopper and returns to the tension abutment state.

[0074] Subsequently, as the first slider moves toward the tip of the swing arm in the latter half of the other return stroke, the tension swing cam that has returned to abutment brings the second slider front block, to which the pedal that moves integrally with the second slider is attached, closest to the tip block of the swing arm with a small gap, completing the entire return stroke. As a result, when viewed from the side of the swing arm, the other pedal axis, in conjunction with the swing of the swing arm, describes a generally oval arc-like locus that is convex and bulges outward toward the fixed swing fulcrum axis by a distance in the base line direction that corresponds to the width of movement of the first slider during the entire return stroke, i.e., by the radius of the crank circle in the practical application.

[0075] The operation of both pedals alternates and rotates continuously, and together with the swing of the swing arm, the operating locus of each pedal axis matches the operating stroke and the return stroke, and has a slight bulge towards the front end of the swing arm, and a bulge towards the rear end by approximately the radius of the crank circle. By properly setting the crank circle diameter, Overall, it has a large front-to-rear width that is roughly the length of a regular crank arm. 、 That is, the short diameter is in the front and rear longitudinal direction and the long diameter is in the up and down direction, which is symmetrical, and is not found in the conventional fixed fulcrum swing arm crank rotary drive system. Has a large front-to-back width The pedal shaft is configured to trace an operating locus of a substantially oval circle that is easily adapted to the folding and pushing movements of a person's legs.

[0076] The tension swing cam comes into contact with or releases from the first slider, switching the movement mode of the first slider and the second slider on which the pedal is mounted. As a result, when the pedal is operated to swing the swing arm, the pedal is fixed in position at the tip end of the swing arm during the operating stroke, and when the operating force on the pedal is released during the return stroke, the first slider and the second slider move synchronously, appropriately setting the trajectory of the pedal axis.

[0077] In this configuration, by making the operating stroke from the highest point to the lowest point and the return stroke from the lowest point to the highest point, a tension swing cam is introduced while minimizing the length of the swing arm, and when the pedal starts to operate, for example when a person presses the pedal with their foot, the pedal position can be moved as far as possible from the fixed swing fulcrum axis of the swing arm, making it possible to utilize the large leverage effect of the swing arm, and also increasing the driving rotation moment around the crankshaft generated by the component force of the pedaling force from the start of pressing, particularly the moment input to the crankshaft including and near the highest point, which in position normally corresponds to the top dead center of the crank, and at least including and near the lowest point, which in position normally corresponds to the bottom dead center of the crank.

[0078] Furthermore, the pedal axis's operating locus, combined with the swing of the swing arm, creates a pedal operating locus that is a roughly oval circle with a large front-to-back width and a symmetrical, vertically long diameter, while increasing the drive rotation moment around the crankshaft and improving the efficiency of the rotation drive. Furthermore, the tip of the tension swing cam is locked in position, causing the second slider to follow, resulting in stable and reliable pedal operation that prevents the pedal from moving backward due to the pedaling force. Furthermore, this pedal-shift type crank rotation drive mechanism significantly reduces the load on the user when operating the crankshaft with leg power compared to conventional fixed-fulcrum swing arm crank rotation drive systems.

[0079] (Features and configuration) The pedal shift-type crank rotation drive mechanism of the present invention includes an elastic tension member having a tip-side abutment portion attached to and held by either the first slider or the second slider, for transmitting a force that moves the second slider to the tip side in the longitudinal direction within a movable range while performing a contact contraction in response to a change in the amount of reduction in the gap between the first slider and the second slider front block; The slider may further include a tension contact member having a tip-side contact portion attached to and held by either the second slider or the first slider.

[0080] (effect) This characteristic configuration has an elastic tension member and a corresponding tension abutment member attached to either the first slider or the second slider, instead of the tension swing cam and first cam roller having the aforementioned tip-side abutment portion. For example, if the elastic tension member is attached to the first slider and the tension abutment member is attached to the second slider, the rear-end abutment surface of the tension abutment member, which forms the tip-side abutment portion of the second slider in the longitudinal direction, and the abutment surfaces of the rear-end abutment portion of the second slider face each other and are held by the swing arm in a state where the first slider is sandwiched at a predetermined distance.

[0081] Furthermore, for the reasons mentioned above, it is desirable that the operating stroke be from the highest point to the lowest point and the return stroke be from the lowest point to the highest point in this configuration. Furthermore, if the rotation range of the crank rotation axis when operating the pedal is from the highest point to the lowest point, and in this configuration, for example, when stepping on the pedal with your foot as on a bicycle, if there is no tension member between the abutment portion on the tip side of the first slider and the abutment portion on the tip side of the second slider, the increase in the drive rotation moment around the crank shaft and the improvement in rotational drive efficiency will be insufficient near the highest point at the start of the pedal stroke, and the path of the pedal axis during one operation of the return stroke will cause a sudden change in the direction of travel of the pedal just before the pedal is pressed down. This is because, in the latter part of the return stroke, as the first slider moves until just before the end of the return stroke, the abutment portion at the tip of the first slider moves without abutting against the abutment portion at the tip of the second slider, and just before the end of the return stroke, the pedal abuts against the abutment portion at the tip of the second slider that has been swinging on the swing arm, causing a sudden change in the direction of the pedal shaft trajectory of the pedal attached to the front block of the second slider.

[0082] While this provides a good opportunity to time the subsequent pedal depression, it is not desirable for the pedal trajectory. The characteristic configuration of this invention aims to improve this sudden change in the direction of the pedal shaft trajectory, and also to further increase the driving rotational moment around the crankshaft and improve the efficiency of the rotational drive, especially when the pedal is depressed near the top of its stroke.

[0083] In other words, by attaching the elastic tension function member of this configuration to a configuration that does not have a tension element, the first slider and the second slider front block come into direct contact in the latter part of the return stroke, and depending on the amount of reduction in the gap between the first slider and the second slider front block, the contact contracts in response to this change, and a pushing force to move is transmitted, thereby avoiding direct contact and preventing a sudden change in the direction of the pedal shaft trajectory, and also moving the pedal as close as possible to the tip of the swing arm at the start of the operating stroke, and increasing the driving rotation moment around the crankshaft near the highest point at the start of depression compared to a configuration without an elastic tension member, thereby improving rotational driving efficiency.

[0084] In addition to mitigating sudden changes in the pedal trajectory direction before the end of the return stroke, the operating trajectory of the pedal axis has a slight bulge at the tip end of the oscillating arm, and when combined with the rear end, it bulges out by more than the radius of the crank circle implemented as a whole, creating a smooth curve that approximates, even if only slightly, a roughly oval circle with a large front-to-back width, a short diameter front-to-back, and a long diameter up-to-down, which is symmetrical, and is not found in conventional fixed fulcrum oscillating arm crank rotary drive systems, thereby greatly reducing the load on the user when operating the crank axis rotation operation using leg strength. [Brief explanation of the drawings]

[0085] [Figure 1] FIG. 1 is an exploded perspective view showing the appearance of a pedal-shift-type crank rotation drive mechanism according to a first embodiment; [Figure 2] FIG. 1 is an exploded perspective view showing a main part of a pedal shift type crank rotation drive mechanism. [Figure 3] An explanatory diagram showing pedal trajectories [Figure 4] FIG. 10 is an explanatory diagram showing the operation of a pedal-shift type crank rotation drive mechanism. [Figure 5] FIG. 1 is an explanatory diagram showing the operation of a main part of a pedal-shift type crank rotation drive mechanism. [Figure 6] An explanatory diagram showing the operating force of the crank pedal [Figure 7] FIG. 10 is a perspective view showing a main part of a pedal according to a second embodiment; [Figure 8] An explanatory diagram showing pedal trajectories [Figure 9] FIG. 10 is an explanatory diagram showing the operation of a pedal-shift type crank rotation drive mechanism. [Figure 10] FIG. 10 is a perspective view showing a main part of a pedal according to a third embodiment. [Figure 11] An explanatory diagram showing pedal trajectories [Figure 12] FIG. 10 is an explanatory diagram showing the operation of a pedal-shift type crank rotation drive mechanism. DETAILED DESCRIPTION OF THE INVENTION

[0086] [First embodiment] (overview)

[0087] The present invention includes a pair of left and right crank arms CA and a crank rotation axis CX2, a pair of left and right swing arms A pivotally supported on a fixed swing fulcrum axis A4 at a position spaced apart from the crank axis CX1 by more than the length of the crank arms CA, a first slider S1 pivotally supported on the crank rotation axis CX2 and reciprocating along the longitudinal direction of the swing arms A, and a first slider S1 that abuts against the first slider S1 as it reciprocates. Also The present invention relates to a pedal-shift type crank rotation drive mechanism Z that includes a second slider S2 that moves back and forth intermittently in the same direction within a movable range without contacting the second slider S2, and a pedal P that is attached to the second slider front block S21 and rotates the crankshaft CX1 while swinging the swing arm A to trace a substantially elliptical locus, and that imparts a rotational output to an output section 5 that rotates integrally with the crankshaft CX1. The present invention simultaneously achieves the following two main objectives.

[0088] The first objective is to create a mechanism that significantly improves the rotational drive efficiency of pedal operation at least at the so-called top dead center and bottom dead center, and in the vicinity of the top dead center and bottom dead center, when a pedal attached to the pedal shaft of a normal crank is depressed and rotated freely.

[0089] The second purpose is to make the operation of the pedal P at the tip of the swing arm A move in a circular trajectory that is more adaptable to the folding and pushing movements of a person's legs, rather than a reciprocating swinging motion along the same trajectory.

[0090] To achieve these two goals simultaneously, the present invention specifically aims to reduce the forward and backward movement of the pedal P by making it smaller than a human walking step but making it as close as possible to the movement of the human leg folding in and out, and by making the path of the pedal axis PX a roughly elliptical path circle with the longest axis in the vertical direction, thereby reducing the power burden of repeated pedaling. This configuration, for example, reduces the burden on the hip joint when operating the pedal P with the human leg, allowing for smooth, continuous operation.

[0091] An embodiment of the present invention applied to a bicycle will be described with reference to Figures 1 to 5. A crankshaft CX1 is supported on a bicycle frame F, and is equipped with a pair of crank arms CA, a crank pivot shaft CX2 (corresponding to the pedal shaft of a normal bicycle), and pedals P, which are positioned laterally opposite each other at a phase angle of 180°. Rotation of both crank pivot shafts CX2 around the crankshaft CX1 rotates the crankshaft CX1, and the resulting output rotates the wheel. In this example, a crank mechanism with a pair of crank arms CA and crank pivot shaft CX2, each of which has a predetermined length shorter than that of a normal bicycle, is used. As mentioned above, this is referred to as the "used crank," and the rotational path of the crank pivot axis CX2a is referred to as the "used crank circle."

[0092] In this embodiment, a pair of left and right swing arms A are provided with a fixed swing fulcrum axis A4 at a position that is longer than the length from the crank shaft CX1 of the crank to the crank arm CA, and swing back and forth at a predetermined angle. orbit The first slider S1, which moves back and forth relatively along the axis CX1a, is rotatably engaged with the crank rotation axis CX2 of the crank employed via a sleeve S11, etc. In this embodiment, the base line connecting the fixed swing fulcrum axis AX and the crank axis CX1a is basically horizontal, but the base line on the side of the crank axis CX1a can be set to Centered on the crank shaft center CX1a, or Swing the fixed swing fulcrum axis AX at an appropriate angle from the horizontal without changing the correlation between the base line and the entire structure. , that is, it should be installed at an angle when viewed from the crankshaft CX1 direction. may be performed.

[0093] In this embodiment, the first slider S1 provided in the longitudinal direction of the swing arm A orbit Same as orbit The second slider S2 moves back and forth relative to the swing arm A along the axis, and in order to give rigidity to the second slider S2, a second slider front block S21 and a second slider rear block S22 that is held by the swing arm A are provided at a predetermined distance apart from each other in the longitudinal direction by which the first slider S1 moves.

[0094] On the other hand, the first slider S1 and the second slider S2 each have one tip-side contact portion. That is, a first cam roller S1c having a first slider tip-side contact portion S1f is attached to the first slider S1, and a tension swing cam 3 having a second slider tip-side contact portion S2f is provided on the second slider S2, which fits between the first cam roller S1c and comes into contact with it to form a tensioned state.

[0095] The rear end surface of the first slider S1 is the first slider rear end abutment portion S1r, and the front end surface of the second slider rear block S22 is the second slider rear end abutment portion S2r. The rear end abutment portion 3r of the tension swing cam 3 and the second slider rear end abutment portion S2r of the second slider rear block S22 face each other in the longitudinal direction and are held by the swing arm A in a state sandwiching the first slider S1 at a predetermined distance. The pair of left and right second sliders S2 have a bifurcated structure with the second slider front block S21 and the second slider rear block S22 connected by a connecting member 21 so as to straddle the first slider S1. A pedal shaft P10 and a rotatable pedal P are attached to the front second slider front block S21. Alternately depressing the left and right pedals P rotates the crank.

[0096] In this configuration, the depression stroke is the travel from the depression start point at approximately the top point of the crank circle (positionally corresponding to the top dead center of a normal crank) to the depression end point at approximately the bottom point (positionally corresponding to the bottom dead center of a normal crank) of the pair of left and right crank arms CA and crank rotation axis CX2, and the return stroke before the depression stroke is the travel from the end point to the start point. The return stroke is performed by the depression strokes on the opposing sides.

[0097] The rotational drive mechanism of the present invention to achieve the first object is that the first slider S1 is held by a pair of left and right oscillating arms A journaled on a fixed oscillating fulcrum axis A4 located at a distance from the crank axis CX1 beyond the length of the crank arms CA, and at the same time, the first slider S1 is held by the crank arm CA located near the highest point of the crank circle, and when the pedal P attached to the second slider front block S21 is always held by the oscillating arm A at a position further forward than the first slider S1, the pedal P can be increased in rotational drive efficiency by pedal operation at least at the highest point PH and the lowest point PL, which correspond in position to the so-called top dead center and bottom dead center of a normal crank, and at the vicinity of the highest point PH and the lowest point PL, by the component of pedal force generated when the pedal depression force is directed in the direction of a line connecting the highest point PH and the lowest point PL drawn when the crank rotation axis CX2 rotates.

[0098] Here, in comparison with the driving rotation moment of a normal crank, the configuration of this embodiment (hereinafter simply referred to as "this configuration") makes it possible to depress the pedal P completely avoiding the so-called top dead center and bottom dead center, and in addition to the effect of the generated depressing force, the effect of the large leverage of the swing arm A makes it possible for the driving rotation moment around the crank shaft CX1 of this configuration to exceed the driving rotation moment of a normal crank in the range from the highest point to the lowest point.

[0099] The second objective is to make the operation of the pedal P at the tip of the swing arm A during the depression stroke and return stroke a circular movement that is more adaptable to the folding and pushing movements of a person's legs, rather than an arcuate reciprocating swinging motion with the same trajectory up and down. In order to achieve this, the example of this embodiment has the following configuration.

[0100] The second slider front block S21, to which the pedal P is already attached, moves back and forth intermittently along the longitudinal direction of the swing arm A, causing the pedal axis center PX to trace a slightly inclined, deformed oval circular path even in the absence of the tension swing cam 3, thereby achieving the present purpose to a large extent. However, the following will explain the configuration in which the pedal axis center PX more reliably traces a vertically symmetrical, deformed oval circular path.

[0101] In this configuration, when depression of one pedal begins at the highest point PH of the crank circle employed in the embodiment, the pedal P moves to the tip of the swing arm A, and during depression of the pedal P to lower the swing arm A to the lowest point PL of the crank circle employed in the embodiment, the pedal P is fixed at the tip of the swing arm A (excluding movement to close the gap) and rotates in an arc-like curved shape with a radius equal to the distance between the pedal axis PX and the fixed swing fulcrum axis AX of the swing arm A. The length of the first slider S1 in the longitudinal direction and the predetermined distance between the mutually facing end faces of the second slider front block S21 and the second slider rear block S22 of the second slider S2 are appropriately set in accordance with the movement width of the first slider S1 so that, at the end of the depression stroke, the rear end face as the first slider rear end abutment portion S1r comes closest to the front end face as the second slider rear end abutment portion S2r of the second slider rear block S22 with a small gap. This is an important prerequisite for this configuration.

[0102] During this time, the other pedal P rotates back as the crank pivot shaft CX2 rotates from the lowest point PL to the highest point PH, which is the return stroke, and is in a state immediately before the start of the next depression stroke. When this pedal P is next depressed, the other pedal P rotates back in a vertically symmetrical modified oval arc shape in conjunction with the rotation of the crank pivot shaft CX2 from the lowest point PL to the highest point PH, in conjunction with the swing of the swing arm A, in a manner that will be described later. Thereafter, the rotation continues.

[0103] In the initial stage of the first half of the return stroke in which this swing arm A rises, the end face of the first slider rear end abutment portion S1r on the side of the first slider S1 facing the fixed swing fulcrum axis A4 abuts against the second slider rear block S22 on the side of the second slider S2 that is closer to the fixed swing fulcrum axis A4, and then the entire second slider S2 is moved toward the fixed swing fulcrum axis A4 a distance equivalent to the movement width of the first slider S1 in the return stroke, i.e., more than the radius of the crank circle in the embodiment.

[0104] Then, in the latter half of the return stroke, the first slider S1 moves the entire second slider S2 toward the tip of the swing arm A by more than the radius of the crank circle used in the actual operation via the tension swing cam 3, which is already in tension abutment due to the biasing force of the biasing spring 4 and the cam positioning stopper 31, thereby completing the return stroke. As a result, the operating locus of the pedal axis PX in the second slider front block S21, coupled with the swing of the swing arm A, causes each pedal axis PX to match the depression (operation) stroke and the return stroke, and in accordance with the forward and backward movement of the pedal P of a normal crank, a large forward and backward movement range not found in conventional fixed fulcrum swing arm crank rotation drive systems, i.e., the swing arm A has a slight bulge toward the tip end and bulges toward the rear end by the radius of the crank circle used in the actual operation, forming a roughly symmetrical, approximately oval circle with a shorter diameter in the front and rear direction and a longer diameter in the up and down direction, which is close to the crank arm length of a normal crank overall and is easy to adapt to the folding and pushing movements of a person's legs.

[0105] Just before the pedal P returns to the tip of the swing arm A, that is, just before the return stroke is completed, the tip of the tension swing cam 3 moves in contact with the second cam roller 3R2, and the posture of the tension swing cam 3 changes against the biasing force of the biasing spring 4, and the contact with the first cam roller S1c is released (Figures 4 and 5).

[0106] 4 shows the movement of the swing arm A and the first slider S1. As shown in FIG. 4F, the timing (lock timing) when the tension swing cam 3 is held by the cam swing / locking portion 3R is just before the crank rotation axis CX2a on which the first slider S1 is pivotally supported reaches the highest point PH, which is the state shown in FIG. 5 in detail. Rotation On the trajectory, the distance between this holding position and the highest point PH in the longitudinal direction of the swing arm A is defined as Sk. This distance Sk is determined by appropriately adjusting the position of the integrated cam swing / locking part 3R having the elongated mounting hole 3Ra in the longitudinal direction of the swing arm A and fixing it to the swing arm tip block A1.

[0107] The integrated cam swing / locking portion 3R is fixed to the swing arm tip block A1 by appropriately adjusting its position in the longitudinal direction of the swing arm A. Thereafter, the posture of the tension swing cam 3 is maintained by the first cam roller S1c (in some cases, one or more) which moves while abutting against the side of the tension swing cam 3, and the tip claw portion 32 of the tension swing cam 3 also maintains a state of engagement with the cam lock pin 3R1.

[0108] On the other hand, the timing at which the tension swing cam 3 is released from its locked state is when the crank rotation axis CX2a passes the lowest point PL by a distance Sk, as shown in Figure 5. At this point, the tension swing cam 3 separates from the second cam roller 3R2, and the biasing spring 4 attached to the tension swing cam 3 changes the posture of the tension swing cam 3, swinging it until it abuts against the cam positioning stopper 31, causing the rear end abutment portion 3r with a radius R to abut against the first cam roller S1c, thereby performing a tension abutment return.

[0109] As a result, the first slider S1 is sandwiched between the tension swing cam 3 and the second slider rear block S22. This occurs immediately before the first slider S1 begins to push the second slider S2 back toward the fixed swing fulcrum axis A4, i.e., toward the rear end, in a tension abutment state. Subsequent movement of the swing arm A toward the rear end in the longitudinal direction ensures an appropriate gap between the rear end face of the first slider S1, which is sandwiched between the tension swing cam 3 and the second slider rear block S22, and the front end face of the second slider rear block S22, to ensure reliable tension abutment return.

[0110] As shown in FIG. 5(a), when there is a gap distance Se between the second slider front block S21 and the swing arm tip block A1 near the end of the pedal depression stroke due to pedal P depression, the pedal depression force causes the second slider S2 to move forward by an additional distance Se, completing the depression. In this case, the first slider S1 returns to the tension contact state just before the gap distance Se from the Sk position. However, at least in the first half of the return stroke, the first slider rear end contact portion S1r of the first slider S1 contacts the second slider rear end contact portion S2r of the second slider rear block S22. In this case, the first slider S1 contacts the tip end face of the second slider rear block S22, pushing the second slider S2 back toward the fixed swing fulcrum axis A4. Therefore, the tension contact state of the tension swing cam 3 only needs to be restored by the time the first slider S1 reaches its closest point to the fixed swing fulcrum axis A4.

[0111] The details of each part of the pedal shift type crank rotation drive mechanism Z according to the first embodiment of the present invention (hereinafter simply referred to as "the mechanism Z") are shown again in FIGS.

[0112] As shown in Figure 1, in this mechanism Z, pedals P are attached to swing arms A that are linked to crank shaft CX1 and crank rotating shaft CX2, and swinging arms A back and forth is caused by alternately stepping on the left and right pedals P. Pedals P are configured to be able to move back and forth along swing arms A, and when swing arms A are stepped on, pedals P are held at approximately the tip of swing arms A.

[0113] 3 and 4, during the depression (operation) stroke from the highest point PH to the lowest point PL by depression of the pedal P, that is, while the pedal axis PX moves from point F to point H in Fig. 3, the tension swing cam 3 remains in the abutment release position and only the first slider S1 moves back and forth toward the tip of the swing arm A, completing the operation stroke. That is, one pedal P and the second slider S2 are held in position at the tip side of the swing arm A while maintaining the longest possible distance from the fixed swing fulcrum axis A4, and together with the swing of the swing arm A, the pedal axis PX describes a circular arc-shaped curved trajectory.

[0114] When pedal P on one of the swing arms A is depressed, the other swing arm A rises. When crank arm CA rotates a quarter turn in the first half of the return stroke of crank pivot axis CX2, the other pedal P is pulled back toward the fixed swing fulcrum axis A4, and then moves toward the tip of swing arm A in the subsequent second half of the quarter turn. The movement locus of pedal axis center PX when viewed along the crank axis CX1 is a roughly elliptical arc that is symmetrical from top to bottom, as shown in Figure 3.

[0115] As mentioned above, by combining the depression (operation) stroke and return stroke, the rotation locus of the pedal axis PX when the crank rotation axis CX2a rotates through one cycle is coupled with the swing of the swing arm A, and in accordance with the forward and backward movement of the pedal P of the normal crank, a large forward and backward movement range not found in conventional fixed fulcrum swing arm crank rotation drive systems is achieved. In other words, the swing arm A has a curved arc shape with a slight bulge toward the tip end, and a deformed elliptical arc shape that bulges out by almost the radius of the crank circle at the rear end. By properly setting the crank circle diameter, In addition, it has a bulge that is close to the length of the crank arm of a normal crank, and is a deformed oval shape that is symmetrical with its upper and lower major axes, which can easily accommodate the folding and pushing movements of a person's legs.

[0116] In this configuration, a tension swing cam 3 is provided across the first slider S1 and the second slider S2. The tension swing cam 3 is pivotally supported by the connecting member 21 of the second slider S2, and a rear end contact portion 3r of the tension swing cam 3 is configured to be able to come into contact with or not come into contact with a first cam roller S1c provided on the first slider S1. When the first slider S1 moves back and forth along the swing arm A, the tension swing cam 3 regulates the position of the second slider S2 so that the second slider S2 does not play relative to the movement of the first slider S1. The specific operation of the tension swing cam 3 will be described later.

[0117] In this way, the pedal P slides relative to the swing arm A, and when the pedal P is depressed in particular, it moves to the most distal end of the swing arm A. As a result, the rotation locus of the pedal axis PX when the crank rotation axis CX2 makes one revolution is significantly forward relative to the circular locus of the crank rotation axis CX2a. Shift the position is formed.

[0118] When operating the pedal P, the movement method and range of movement that can withstand, for example, prolonged pedaling motion of a person's legs are limited, so the length of the crank arm in a typical pedal operation using a normal crank is set appropriately depending on the user and the conditions of use. In contrast, in this embodiment, to achieve a compact device, the distance from the crank axis CX1a to the pedal axis PX, i.e., the arm length of the practical crank, is set to a length equal to or shorter than the length of each crank arm appropriately set for a typical normal crank. In this case, the rotational trajectory of the crank rotation axis CX2a that should be on the appropriately set crank arm is referred to here as the comparative crank circle.

[0119] Figure 3 compares the trajectory T1 of the crank circle according to the crank rotation axis CX2a in this embodiment with the trajectory T2 of the comparative crank circle according to a normal crank rotation. From the above, the practical crank circle is necessarily smaller in diameter than the comparative crank circle. However, while it is naturally made considerably smaller than a human walking step, it is preferable to make it as close as possible to the front-to-rear width that corresponds to the folding and pushing movements of the user's legs. Note that Figure 3 also shows the trajectory of the pedal axis PX.

[0120] In Figure 3, the locus of the pedal axis center PX of this embodiment passes outside the circular locus of a conventional pedal from point D to point G and from point G to point J. These positions correspond to the region where the crank rotation axis center CX2a passes over top dead center d and reaches bottom dead center j. Because the center of rotation of the pedal at these positions is the fixed swing fulcrum axis AX, the pedal force required is significantly reduced.

[0121] On the other hand, when the depression stroke is completed and the crank rotation axis CX2a returns from the lowest point PL to point A, the first slider S1 pulls the second slider S2 back toward the fixed swing fulcrum axis A4, causing the pedal P to rise in a curved line. As a result, the path of the pedal axis PX in one revolution becomes a deformed ellipse that is symmetrical in the vertical major axis, providing a mechanism that allows the user to naturally fold and push out their legs.

[0122] FIG. 6 shows the trajectory T1 of the crank rotation axis CX2a according to this embodiment (the crank circle used in the embodiment) and the trajectory T2 of the pedal according to a conventional crank mechanism (the crank circle for comparison). The direction of the pedal depression force Fa on the pedal P is assumed to be the direction of a line (reference line) connecting the highest point PH and the lowest point PL of the rotation trajectory of the crank rotation axis CX2a. A force acting at the intersection P1 of the trajectory T1 and a line passing through the crank axis CX1a and forming an arbitrary angle θ with the reference line is defined. Here, the angle formed by the center line of the swing arm A and the line connecting the fixed swing fulcrum axis AX and the crank axis CX1a is defined as α.

[0123] Since the above-mentioned downward pedal force Fa acts on the pedal axis PX, the pedal force component Fm1 perpendicular to the swing arm A at the pedal axis PX is Fa·cosα. Based on this Fm1, a force k·Fm1, that is, k·Fa·cosα, acts parallel to Fm1 at the intersection P1. k is the leverage ratio expressed as L2 (length of line segment AX-PX) / L1 (length of line segment AX-P1). Also, the force in the direction tangent to the locus T1 at the intersection P1 is k·Fa·cosα·sin(θ+α).

[0124] Here, if r1 is the radius of the locus T1 and r2 is the radius of the locus T2, then The driving rotation moment Ma1 around the crankshaft CX1 at the intersection P1 is Ma1=k·r1·Fa·cosα·sin(θ+α) ···(1) It is expressed as: Here, when θ is zero, that is, the basic included angle formed by the line segments AX-CX1a and AX-PH is α0. As θ increases from 0 degrees to 90 degrees, L1 increases, but α decreases from α0 to 0 degrees.

[0125] α0 is determined by the relationship between the fixed swing fulcrum axis AX and the locus T1, but taking into consideration the length of the swing arm A, the size of the elemental members, the stepping position, height, stroke, etc., the desirable range is between 20 degrees and 35 degrees. However, the most effective angle is about 25 degrees to 30 degrees. For example, if α=α0=25 degrees, then sinα0=0.42, and cosα0 is about 0.91. Therefore, when the pedal P is at the highest point PH, Ma1≒0.38·r1(L2 / L1)·Fa···(2) If α=α0=30 degrees, sinα0=0.5, cosα0 is about 0.87, Therefore, Ma1≒0.44·r1(L2 / L1)·Fa···(3) This becomes:

[0126] These facts show that when θ is zero at the highest point PH, the operating force component effect due to α0 does not generate any operating force that contributes to the crankshaft drive rotational moment at top dead center with a normal crank, and is zero; however, as a rough ratio to the maximum drive rotational moment (k·r1·Fa) when θ is 90 degrees, when α0 is 25 degrees or 30 degrees, an operating force component effect of 0.38 or 0.44 ratio is generated, and furthermore, a maximum leverage effect of (L2 / L1) is added within the change.

[0127] During the depression stroke of the pedal P, that is, the region where the crank rotation axis CX2a moves from the highest point PH to the lowest point PL, L2 is constant, so the leverage ratio k = (L2 / L1) is maximum at the highest point PH and the lowest point PL. In this configuration, the function of the tension swing cam 3 is to move the position of the pedal P to the tip of the swing arm A when the crank rotation axis CX2a is at the highest point PH, so that a larger rotational moment can be applied to the crank arm CA than at the beginning of the depression stroke.

[0128] In other words, the leverage ratio k of the pedal shift type rotary drive mechanism Z having this configuration increases the closer it is to the highest point PH, which normally corresponds to the top dead center of a crank, and the drive rotational moment also increases due to this leverage action, so it is a rational means that is well suited, together with the pedal depression operating force, to increase the rotational moment near the highest point, which normally corresponds to the so-called top dead center of a crank.

[0129] Furthermore, with this configuration, the change in the drive rotational moment about the crank axis CX1a in the second half of the pedal depression stroke, when θ has completed the first half of the pedal depression stroke, passed the midpoint of 90 degrees, and reached the lowest point PL of 180 degrees, is symmetrical above and below the line segment AX-CX1a, and the improvement in the drive rotational moment about the crank axis CX1 throughout the pedal depression stroke is exerted near the lowest point PL as well as near the highest point PH, and is approximately twice as effective as it was up to the midpoint where θ is 90 degrees.

[0130] Here, we will provide additional information on differences between this configuration and other embodiments. Specifically, L2 is not constant in the first half of the depression stroke but, like L1, varies with θ. When θ is 0 degrees, i.e., at the top of the crank circle in the practical application, L2 is at its minimum, and the leverage ratio k = (L2 / L1) is not necessarily at its maximum. Therefore, the change in the driving torque around the crank axis CX1 in the first and second half of the depression stroke may not be symmetrical across a horizontal line passing through the fixed pivot axis AX and the crank axis CX1a. However, in this case, the leverage ratio k exceeds 1 even in the first half of the depression stroke, up to 90 degrees, so the leverage effect remains. Furthermore, in the second half of the depression stroke, when θ exceeds 90 degrees, L2 remains constant at its maximum length when the pedal P is positioned at the very end of the upper movable range of the swing arm A while the depression force remains applied. However, as L1 decreases, the driving torque near the bottom increases significantly. Therefore, even in this case, in addition to the depression operating force component, the effect of improving the driving rotation moment around the crankshaft CX1 throughout the entire pedal depression stroke is exerted.

[0131] (crank arm) As shown in Fig. 1, a pair of left and right crank arms CA are attached to a frame F of a bicycle or the like. The left and right crank arms CA extend radially from a crankshaft CX1 with a phase angle difference of 180 degrees. A sprocket 50 is attached to the crankshaft CX1 as an output unit 5 that transmits the rotation of the crankshaft CX1 to, for example, a rear wheel.

[0132] A crank rotation axis CX2 (to be described later) extends outward from the tip of each of the left and right crank arms CA in parallel with the crank axis CX1.

[0133] (swinging arm) A fixed swing fulcrum shaft A4, which is different from the crankshaft CX1, is provided on the frame F at a position that is longer than the length of the crank arm CA, and the swing arm A is journaled on this fixed swing fulcrum shaft A4. The fixed swing fulcrum shaft A4 is, for example, provided at approximately the same height as the crankshaft CX1 and at the rear. The swing arm A holds the first slider S1, the second slider S2, and the pedal P.

[0134] (First slider) As shown in Figures 1 and 2, a first slider S1 is attached to the crank rotation axis CX2 of the crank arm CA via a rotatable sleeve S11. As a trajectory The first slider S1 is inserted via linear bearings or the like onto two guide bars A3 provided on the swing arm A. This allows the first slider S1 to smoothly reciprocate on the swing arm A in accordance with the rotation of the crank arm CA.

[0135] (Second slider) A second slider S2, which follows the reciprocating movement of the first slider S1, is attached to the two guide bars A3 of the swing arm A so as to be able to move back and forth, similarly via linear bearings. The second slider S2 is made up of a second slider front block S21 and a second slider rear block S22, which are connected in a bifurcated manner by a connecting member 21. A pedal P is journaled on the second slider front block S21. The reciprocating movement of the second slider S2 along the guide bars A3, combined with the swinging of the swing arm A, allows the movement locus of the pedal axis center PX to become a vertically symmetrical deformed elliptical shape with a large forward and backward movement range when viewed in the direction along the crank axis center CX1a.

[0136] Specifically, during the depression stroke in which the swing arm A is depressed, the pedal P is fixed to the tip of the swing arm A and descends in an arc. On the other hand, during the return stroke in which the pedal P rises, the movement of the first slider S1 and the second slider S2 causes the pedal P to rise in a substantially elliptical arc in conjunction with the swing of the swing arm A. When the arc during depression and the modified elliptical arc during return are combined, the movement locus of the pedal axis PX becomes a vertically symmetrical modified elliptical shape with a large forward / backward movement range.

[0137] (pedal) The rotatable pedal P is attached to the second slider front block S21 of the second slider S2. It may be attached to any part of the second slider S2, including the connecting member 21, but it should be located in a position that does not interfere with the operation of the first slider S1, the swing arm A, or the tension swing cam 3 described below.

[0138] (Tension swing cam) As shown in FIGS. 2 to 4, the relative movement of the first slider S1 and the second slider S2 is controlled by a tension swing cam 3. When the swing arm A is depressed by the pedal P and the crank arm CA is pushed down (FIGS. 3 and 4F, G, and H), the second slider S2 moves toward the tip of the swing arm A. As the pedal P moves to the tip of the swing arm A, the maximum length of pedal movement of the swing arm A is used to increase the rotational moment about the crank axis CX1 from the start of depression, and the crank arm CA can be efficiently pushed down. In addition, this, combined with the swing of the swing arm A, allows the movement locus of the pedal axis PX to be an elliptical arc that is vertically symmetrical when viewed in the direction along the crank axis CX1a.

[0139] On the other hand, when the axis CX2a of the crank pivot shaft CX2 attached to the crank arm CA passes the lowest point PL on the crank circle and heads toward the highest point PH, the swing arm A is driven upward by the action of the first slider S1 due to depression of the opposing pedal P. When the first slider S1 rises from the lowest point PL past the depression end point i, the first slider S1 abuts against the second slider rear block S22, and the second slider S2 is returned toward the fixed swing fulcrum axis A4. In combination with the swing of the swing arm A, the pedal axis PX rises following a modified elliptical arc trajectory that bulges out by the length of the crank arm CA.

[0140] At this time, the tension swing cam 3 attached to the second slider S2 comes into contact with or close to the first cam roller S1c attached to the first slider S1 due to the biasing spring 4, and the first slider S1 is positioned between the tension swing cam 3 and the second slider rear block S22. This prevents the second slider S2, and therefore the pedal P, from moving backward or rattling along the swing arm A when the swing arm A rises.

[0141] (First cam roller and second cam roller) 1 and 2, to achieve the operating function of the tension swing cam 3, a first cam roller S1c is provided on the first slider S1, and a second cam roller 3R2 is provided on the swing arm tip block A1. While the axis CX2a of the crank rotation shaft CX2, on which the first slider S1 is journaled, moves from the lowest point PL to the highest point PH, the R-shaped rear end abutment portion 3r of the tension swing cam 3 abuts or approaches the first cam roller S1c due to the biasing force of the biasing spring 4 and the cam positioning stopper 31. As a result, the first slider S1 is sandwiched between the second slider rear block S22 and the tension swing cam 3, and the second slider S2 follows the movement of the first slider S1 without moving backward or rattling.

[0142] After this, just before the axis CX2a of the crank pivot shaft CX2, on which the first slider S1 is journaled, reaches the highest point PH on the locus T1 of the crank pivot axis CX2a, the inclined side surface 33 at the tip of the tension swing cam 3 abuts against the second cam roller 3R2. The tension swing cam 3, in a tension-contact state, begins to rotate against the biasing force of the biasing spring 4. The first slider S1 moves further, and as shown in FIG. 4F, the inclined side surface 33 formed on the tension swing cam 3 is pushed by the second cam roller 3R2 and rotates, and the tip claw portion 32 engages with the cam lock pin 3R1. Simultaneously, the tension swing cam 3 releases its tension abutment against the first cam roller S1c. At this point, the second slider front block S21 has reached the vicinity of the rear end face of the swing arm tip block A1.

[0143] 4F, G, and H, the posture of the tension swing cam 3 is maintained by the first cam roller S1c (or one or more rollers, as the case may be) that moves while abutting against the side of the tension swing cam 3, and the tip claw portion 32 of the tension swing cam 3 is maintained in engagement with the cam lock pin 3R1. In this state, the second slider S2 is prevented from returning along the swing arm A toward the fixed swing fulcrum axis A4. After this, while the axis CX2a of the crank rotating shaft CX2, on which the first slider S1 is pivotally supported, moves from the highest point PH to the lowest point PL, the pedal P attached to the second slider front block S21 is held at the tip end position of the swing arm A. As a result, as shown by the thick solid line in FIG. 3, the trajectory of the pedal axis center PX from point F to point H, in conjunction with the swing of the swing arm A, forms an arc with the maximum radius centered on the fixed swing fulcrum axis AX.

[0144] A major feature of the rotational drive mechanism in the configuration of this mechanism Z is the interlocking movement of two rotational systems: the rotational system of the swing arm A having a fixed swing fulcrum axis A4, and the rotational system of the crank (the crank used in this configuration) having a fulcrum at the crank axis CX1. This interlocking is achieved by the operation of a pair of left and right pedals P located always distal to the first slider S1 of the swing arm A, under the condition that the first slider S1 held by a pair of left and right swing arms A journaled on the fixed swing fulcrum axis A4 is rotatably supported on the crank pivot axis CX2 and is capable of reciprocating movement along the longitudinal direction of the swing arm A. By depressing one of the pedals P within the range of the depression stroke to partially rotate the swing arm A (here, depressing and swinging), the crank pivot axis CX2 receives an acting force increased by the leverage ratio in the direction of the swing action component force, and the crank simultaneously performs a half rotation with the crank axis CX1 as the fulcrum.

[0145] For comparison, Figure 3 shows the locus T2 of a crank mechanism with a normal circular locus by a dot-dash line. Here, the change in the direction of movement on locus T2 from the highest point T2f of the circular locus to point g' is greater than the change in the direction of movement on the locus of the pedal axis PX from point F to point G. For this reason, on locus T2 of the conventional mechanism, the angle between the direction of depression of pedal P and the locus is large, and the depression force contributing to the movement of pedal P is reduced.

[0146] In the mechanism Z of this configuration, the trajectory of the pedal axis PX as the crank rotation axis CX2a moves from the highest point PH to the lowest point PL is an arc, and by bringing the movement direction of the pedal axis PX closer to the direction in which the pedal P is depressed, the leg force applied to the pedal P due to the depression force component can be effectively utilized, and this is also effective in reducing ankle fatigue.

[0147] (Second embodiment) As shown in FIGS. 7 to 9, the pedal shift type crank rotation drive mechanism Z of this embodiment can be configured without the tension swing cam 3 in the first embodiment. In this embodiment, there is no tension swing cam 3 between the first slider S1 and the second slider S2, and the relative positional relationship between them can be easily changed. For this reason, the fixed swing fulcrum axis AX is inclined upward with respect to the crank axis CX1a so that the second slider S2 holding the pedal P can slide as easily as possible forward of the swing arm A when the pedal P is depressed. In other words, the base line on the side of the fixed swing fulcrum axis A4 is swung by an appropriate angle β from the horizontal in the direction of the highest point PH around the crank axis CX1a, not the fixed swing fulcrum axis AX, without changing the correlation between the base line and the entire configuration. In other words, when viewed from the crankshaft CX1 direction, the angle is changed. Put it on.

[0148] In this embodiment, the range of the operating stroke in which one pedal performs the depressing action is set from the highest point to the lowest point on the locus of the crank rotation axis, and the range of the return stroke in which the other pedal performs the return action is set from the lowest point to the highest point.

[0149] One reason for this configuration is the reliability of the pedal P depression action. In other words, the bottom dead center is the point of contact between the lower tangent drawn from the fixed swing fulcrum axis AX to the actual crank circle and the actual crank circle, so the swing arm A has a large positional fluctuation relative to the swing contact angle, which is prone to uncertainty due to variations in the operation of the pedal P. On the other hand, at the lowest point PL, the pedal P depression action is still in a definite state. Therefore, the highest point PH, which is a phase angle difference position 180 degrees back from the lowest point PL around the crank axis CX1a, is set as the starting point of the pedal depression action.

[0150] Other reasons include: By doing so, in this configuration The crank rotation axis CX2a on the crank circle is used is back Crank at the beginning of the stroke lowest point From the position closest to the fixed swing fulcrum axis A4, that is, until it reaches the line connecting the fixed swing fulcrum axis AX and the crank axis CX1a When Pedal shaft center PX circle The front-to-back width of the trajectory, In the case of the operating stroke from the line symmetric point of the top dead center to the bottom dead center The front-to-back width at the beginning of the return stroke from the bottom dead center of the crank rotation axis CX2a to the position closest to the fixed swing fulcrum axis A4. It can be made larger and can be made easier to accommodate the folding and sending out movements of the legs, especially when stepping on them with a human leg.

[0151] In the first stage of the operating stroke, the pedal P is operated to rotate the swing arm A, and the first slider S1 is moved via the crank rotation shaft CX2, causing the entire second slider S2 to move until it abuts against the swing arm tip block A1.

[0152] During the remaining second stage of the crank arm CA's operating stroke, which is the first half of its rotation, only the first slider moves toward the fixed swing fulcrum axis A4 until the crank rotation axis CX2a reaches its lowest point PL, i.e., from point G to point H in FIGS. 8 and 9. However, the pedal P attached to the second slider front block S21 ends its operating stroke in contact with the swing arm tip block A1 due to the opposing directions of the operating forces. As a result, the pedal axis PX, in conjunction with the swing of the swing arm A, describes a partial arc locus whose radius is the distance from the fixed swing fulcrum axis AX to the pedal axis PX. At this time, the first slider rear abutment region S1r, i.e., the rear end face, approaches the second slider rear abutment region S2r without coming into contact with it until the axis CX2a of the crank rotation axis CX2 supporting the first slider S1 reaches its lowest point PL.

[0153] However, when one pedal P is depressed during the operating stroke, the crank rotation axis CX2a passes the lowest point PL and heads toward the bottom dead center due to inertia, etc., and even if the crank arm CA tries to rotate further, the first slider S1 on that side immediately comes into contact with the second slider rear end abutment portion S2r, preventing operation, and the axis CX2a of the crank rotation axis CX2 on which the first slider S1 is pivotally supported ends the operating stroke without moving significantly beyond the lowest point PL. Then, when the other pedal P is subsequently operated, the return stroke of one crank rotation axis CX2a begins, and with the first slider rear end abutment portion S1r on that side coming into contact with the second slider rear end abutment portion S2r, both begin to move toward the rear end of the swing arm A, and the pedal P is pulled back toward the fixed swing fulcrum axis A4.

[0154] In other words, at the same time, the other pedal P is depressed to start the operating stroke, and the other crank rotation axis CX2a passes the highest point PH, and the first slider S1 abuts against the abutment portion S2f on the tip side of the second slider, and the operating stroke is carried out so that the other pedal P is pushed toward the tip side of the swing arm A.

[0155] One of the prerequisites for this operation, the first slider rear end contact portion S1r, does not contact the second slider rear end contact portion S2r until the crank rotation axis CX2a reaches its lowest point (the first prerequisite). If the first slider rear end contact portion S1r contacts the second slider rear end contact portion S2r at the end of the pedal P depression stroke before the crank rotation axis CX2a reaches approximately its lowest point PL, the rotational force acting on the crank rotation axis CX2 and the downward actuation force acting on the pedal P will be in opposition, preventing the crank from rotating. The opposing crank rotation axis CX2 will not reach its actuation start point, i.e., its highest point PH. This will result in an insufficient actuation force due to continued pedal depression (actuation), affecting the crank rotation. For this reason, the first prerequisite, along with the second prerequisite of minimizing the length of the swing arm A, is highly important.

[0156] Meanwhile, the return stroke in which the pedal P returns is as follows: In the first part of the return stroke, when one pedal P rotates the crank arm CA during the return stroke by depressing the opposing pedal P, for example, the crank arm CA rotates upward from the lowest point PL, which is the end point of the crank circle in the embodiment, to a line passing through the fixed swing fulcrum axis AX of the swing arm A and the crank axis CX1a. Immediately after the start of the return stroke, the first slider rear-end abutment site S1r, i.e., the rear end face, on the swing arm A abuts the second slider rear-end abutment site S2r, and the entire second slider S2 moves toward the fixed swing fulcrum axis A4 until it comes closest to the rear-end block A2 on the fixed swing fulcrum axis A4 side of the swing arm A without coming into contact with it. Accordingly, the pedal P attached to the second slider front block S21 also comes closest to the fixed swing fulcrum axis A4 by the same distance. As a result, as mentioned above, the pedal axis PX, in conjunction with the swing of the swing arm A, describes an arc of about a quarter of a modified ellipse that bulges out toward the rear end of the base line by approximately the radius of the crank circle.

[0157] In the latter part of the return stroke, in which the crank arm CA continues to rotate to the highest point PH, only the first slider S1 moves toward the tip of the swing arm A according to the trajectory of the crank circle employed, and ideally, the first slider tip abutment portion S1f, i.e., the tip end face, comes closest to the tip abutment portion S2f, i.e., the rear end face of the second slider front block S21, without coming into contact with it, and the return stroke ends.

[0158] During this time, i.e., in the latter part of the return stroke, the second slider S2 remains stopped in the longitudinal direction of the swing arm A, and therefore, in conjunction with the swing of the swing arm A, the pedal axis center PX of the pedal P attached to the second slider front block S21 describes a partial arc curved locus pointing upward in the rear direction, with the radius being the distance from the fixed swing fulcrum axis A4 to the pedal axis center PX.

[0159] However, in this case, by setting the length of the swing arm A, which is the second prerequisite, to the minimum possible length, the leading end face of the first slider S1 will come into contact with the rear end face of the second slider front block S21, to which the pedal P, which has been swinging in an upward, partially arcuate trajectory, is attached, not at the transition between strokes but at approximately top dead center just before the crank rotation axis CX2a reaches the actuation start point, i.e., the highest point PH, during the latter part of the return stroke, causing a sudden change in direction and creating an uneven trajectory for the pedal axis PX. While this is not desirable for the movement of the pedal P, it provides a good opportunity to time the subsequent pedal depression in use.

[0160] In this configuration, the first slider S1 pivotally supported on the crank rotation shaft CX2 performs a continuous sliding movement, but the second slider front block S21 to which the pedal P is attached moves indirectly and intermittently along the swing arm A only by contact with the first slider S1. Therefore, the entire mechanism is tilted by an appropriate angle β that is smaller than the basic narrow angle α0. In other words, it is installed at an angle when viewed from the crankshaft CX1 direction.This allows the second slider front block S21, to which the pedal P is attached, to slide more easily in response to the user's depressing action. In other words, the pedal P can achieve both sliding and rotating actions while having a simpler structure than the components of the first embodiment. Therefore, compared to the conventional fixed fulcrum swing arm crank rotation drive system, the user can operate the pedal without any discomfort.

[0161] The basic angle α0 between the basic line connecting the fixed swing fulcrum axis AX and the crank axis CX1a and the tangent line drawn from the fixed swing fulcrum axis AX to the crank circle employed is preferably between 20 degrees and 35 degrees, taking into consideration the length of the swing arm A, the size of the elemental members, the depression position, the stroke, etc. Within this range, a value between 25 degrees and 30 degrees is most effective.

[0162] As described above, under the correct operation of this embodiment, the pedal axis PX moves in conjunction with the swing of the swing arm A. Overall, the crankshaft expands forward and backward by more than the radius of the crankshaft circle, and by approximately the normal crank arm length depending on the crankshaft circle diameter. The pedal P traces a trajectory of a deformed elliptical circle with a vertically longer axis that is slightly inclined toward the tip end of the longitudinal direction of the swing arm A. The pedal P itself moves longitudinally while moving up and down on the swing arm A. As a result, the effect of this configuration is that, for example, when using the swing arm A to step on the pedal P with the foot to operate and rotate the crank arm CA, the pedal movement follows a circular trajectory that is easily adapted to the folding and pushing movements of a person's leg, and it becomes possible to pedal along a rotation trajectory that reduces fatigue in the operator's legs. This is the first effect of this configuration.

[0163] The highest point PH and lowest point PL are approximately the start and end points of the depression (operation) stroke, making it possible to depression without completely avoiding top dead center and bottom dead center. The depression operating force generated overall, and particularly the large leverage of swing arm A in the remaining latter rotation of the depression (operation) stroke, improve the efficiency of rotational drive, at least at and near the highest point PH, which normally corresponds to the top dead center of a crank, and at least at and near the lowest point PL, which normally corresponds to the bottom dead center of a crank, which has been the biggest problem with conventional crank rotational drives. This is the second effect of this configuration.

[0164] When the rotation range of the crank rotation axis CX2a when the pedal P is depressed (activated) is from the highest point PH to the lowest point PL, the distance between the second slider tip abutment point S2f and the second slider rear end abutment point S2r is such that when one crank rotation axis CX2a reaches the lowest point PL, which is the end point of the depression stroke, in the crank circle employed in the embodiment, the rear end surface of the first slider S1 on that side is positioned at the second slider rear end abutment point S2r with the minimum required gap between them.

[0165] On the other hand, at that time, the second slider front block S21 is pressed against the swing arm tip block A1 by stepping on the pedal P attached to it, so the set distance in this embodiment is the distance between the second slider tip side abutment portion S2f and the second slider rear end side abutment portion S2r at this time.

[0166] Therefore, it is calculated from the longitudinal movement distance of the swing arm A when the crank rotation axis CX2a on which the first slider S1 is pivotally supported moves from the point farthest from the fixed swing fulcrum axis AX to the lowest point PL, i.e., the movement distance of the first slider S1 in the latter stage of the depression (operation) stroke, plus the longitudinal width of the first slider S1 and the minimum required gap.

[0167] Regarding the minimum required length of the swing arm A, first the basic narrow angle and the crank circle radius to be used are set, and then the distance from the fixed swing fulcrum axis AX to the crank axis CX1a is determined. When the crank rotation axis CX2a is at the position farthest from the fixed swing fulcrum axis AX in the practically employed crank circle, that is, when it is at the intersection of the extension line connecting the fixed swing fulcrum axis AX and the crank axis CX1a, the second slider front block S21 is positioned with an appropriate gap at the tip side of the first slider S1 journaled on the crank rotation axis CX2, and the swing arm tip block A1 is further positioned with an appropriate gap at its tip side, the length of the swing arm A is determined by determining the radius of the practically employed crank circle and the dimensions of the second slider front block S21 and the second slider rear block S22 in relation to the distance from the fixed swing fulcrum axis AX to the crank axis CX1a, and the dimension of the tip side of the swing arm A from the fixed swing fulcrum axis AX that should slidably hold the second slider S2 is determined (excluding gaps at each appropriate location).

[0168] Once these dimensions are determined, the gap dimensions to be set between the first slider S1, the second slider S2 and the swing arm A can be easily determined.

[0169] When setting the dimensions of this mechanism in this embodiment, it is advisable to determine the dimensions of each part based on the basic idea of ​​satisfying the design specifications of the first premise first condition and second premise mentioned above, so that the user can easily fold and push out their legs and fatigue in the legs is reduced.

[0170] Furthermore, if the direction of operation (stepping) is properly adjusted in an object that is operated or stepped on by a person's arms or legs, the features of this configuration can be maximized, leading to more uses and being advantageous for this configuration. In other words, it should be installed at an angle when viewed from the crankshaft CX1 direction. On the other hand, the device of this configuration can also be effectively used in devices that are not operated by a person.

[0171] (Third embodiment) As shown in the second embodiment, in a configuration in which there is no tension oscillating cam 3 between the first slider tip end contact portion S1f and the second slider tip end contact portion S2f, the increase in the driving rotational moment around the crankshaft CX1 and the improvement in the efficiency of the rotational drive are insufficient near the approximately highest point PH at the start of depression, and in the trajectory of the pedal axis center PX during one operation of the return stroke, there is a point where the direction of travel of the pedal P suddenly changes just before depression.

[0172] This occurs when the first slider tip abutment portion S1f moves without abutting the second slider tip abutment portion S2f until the end of the return stroke, and then suddenly abuts against it before the end, causing a sudden change in the direction of movement of the pedal axis PX. This can be a good opportunity to determine the timing of the pedal P depression operation, but it can also be a good opportunity to determine the timing of the pedal P operation. The characteristic configuration of this embodiment is to improve this sudden change in the trajectory direction of the pedal axis PX, and to move the pedal P farther from the fixed swing fulcrum axis AX of the swing arm A, thereby increasing the driving rotation moment around the crankshaft CX1 when the pedal P is depressed and improving the efficiency of the rotational drive.

[0173] Here, we will discuss an embodiment in which the gap between the second slider tip end contact portion S2f and the second slider rear end contact portion S2r is set based on the movement width of the first slider S1 during the depression (operation) stroke, thereby keeping the length of the oscillating arm A to a necessary minimum.

[0174] In this embodiment, as described above, the pedal P is moved closer to the tip of the swing arm A, and compared to when there is no elastic tension member N, etc., when the rotational drive begins, the first slider S1 has already moved, for example, about half the distance traveled in the first stage of the depression (operation) stroke toward the tip, and the depression stroke continues as the pedal P, which is further on the tip side, is depressed.

[0175] Furthermore, when implementing this configuration, the emphasis is placed on slightly lowering the lowest position of the pedal axle P10 that is stepped on within the vertical range of motion of the human leg, while also lowering the highest position by the same amount to keep the height down. For example, the height is set to about the same as the highest point of the crank circle for comparison, based on the length of the crank arm of each size that is appropriately set for a normal bicycle. For this reason, the following usage is adopted here. That is, because the aforementioned fore-aft width of the pedal axle circle path can be increased, the rotation range of the crank rotation axis CX2a when the pedal P is stepped on is set from the highest point PH to the lowest point PL, and the base line on the side of the fixed oscillation fulcrum axis A4 is swung by an appropriate angle from the horizontal in the direction of the highest point PH, centered on the crank axis CX1a rather than the fixed oscillation fulcrum axis AX, without changing the correlation between the base line and the entire configuration. In other words, when viewed from the crankshaft CX1 direction, the angle is changed. Put it on.

[0176] 10 to 12 show a pedal shift-type crank rotation drive mechanism Z of a third embodiment. In this embodiment, instead of the tension swing cam 3 and first cam roller S1c described above, an elastic tension member N and a corresponding tension abutment member Nt are provided on either the first slider S1 or the second slider S2.

[0177] For example, as shown in Figure 10, if an elastic tension member N is provided on the first slider S1 and the abutment portion S2f on the tip end of the second slider is made to be a tension abutment member Nt, the abutment surfaces of the tension abutment member Nt and the abutment portion S2r on the rear end of the second slider are held by the swing arm A in a state where the first slider S1 is sandwiched at a predetermined distance and facing each other.

[0178] The elastic tension member N and the tension abutment member Nt abut in accordance with the amount of reduction in the distance between the first slider S1 and the second slider front block S21, and as the elastic tension member N contracts, it moves the second slider S2 toward the tip end in the longitudinal direction within its movable range.

[0179] In this embodiment, in order to provide rigidity to the second slider S2, a second slider front block S21 is provided which moves back and forth relative to the swing arm A along the same trajectory as the trajectory of the first slider S1, and a second slider rear block S22 is provided which is held by the swing arm A at a predetermined distance from the second slider front block S21 in the longitudinal direction.

[0180] The second slider front block S21 and the second slider rear block S22 are connected by a bifurcated connecting member 21 so as to straddle the first slider S1. A pedal shaft P10 and a rotatable pedal P are attached to each of the left and right second slider front blocks S21. Alternately pressing down on the left and right pedals P causes the crank to rotate.

[0181] By attaching the elastic tension member N and tension abutment member Nt of this configuration, when the first slider S1 and the second slider front block S21 come into contact and contract, a pushing force is transmitted from the first slider S1 to the second slider front block S21, and when the pedal P starts its operating stroke, the pedal P is moved even slightly toward the tip of the swing arm A. This makes it possible to improve the rotational drive efficiency near the highest point PH compared to when the elastic tension member N is not used.

[0182] Also, The sudden change in the trajectory direction of the pedal P before the end of the return stroke is alleviated, and the operating trajectory of the pedal axis PX is slightly expanded toward the tip end of the swing arm A, and expanded toward the rear end by the radius of the crank circle, so that the overall shape is the same as that of a normal crank. The front-to-back width is close to the crank arm length. The short diameter is in the front-to-back direction and the long diameter is in the up-to-down direction, and the shape is a symmetrical, approximately oval circle with a smooth curve. can .

[0183] In this embodiment, the elastic tension member N is provided on the first slider S1, and the tension abutment member Nt is provided on the second slider front block S21. The elastic tension member N consists of a compression coil spring N1, a spring holding shaft N2 into which the compression coil spring N1 is inserted and held, and a tension bearing member N4 having a bearing hole N3 that supports the spring holding shaft N2 and allows it to slide in the longitudinal direction. The tension abutment member Nt, which abuts against the tip of the spring holding shaft N2 to receive the biasing force of the compression coil spring N1, is attached to the second slider front block S21, and its rear end in the longitudinal direction forms the second slider tip-side abutment portion S2f.

[0184] The end of the spring holder shaft N2 on the tension abutment member Nt side is flange-shaped and serves as an extended abutment portion for the compression coil spring N1, also serving as the first slider tip-side abutment portion S1f. The opposite end is threaded, and a double lock nut N5 or the like prevents the spring holder shaft N2 from slipping out of the tension bearing member N4 due to the biasing force of the compression coil spring N1. This double lock nut N5 also serves to adjust the length of protrusion of the spring holder shaft N2 from the tension bearing member N4.

[0185] This adjustment makes it possible to determine the timing at which the tip of the spring holding shaft N2 contacts the tension contact member Nt during the latter half of the return stroke of one pedal P. Of course, the tip of the spring holding shaft N2 may be brought into contact with the tension contact member Nt and the biasing force of the compression coil spring N1 may be applied from the very beginning of the latter half of the return stroke of the pedal P.

[0186] The compression coil spring N1, spring holding shaft N2, tension bearing member N4, tension abutment member Nt, etc. are attached to the first slider S1 and the second slider front block S21, respectively, so as to be located below the swing arm A. In this case, a step portion N4a is provided in the tension bearing member N4, and a space is provided in which the compression coil spring N1 in a compressed state can be held even when the first slider S1 and the second slider front block S21 abut against each other.

[0187] By providing the elastic tension member N in this manner, it contributes to improving the rotational drive efficiency at and around the highest point PH, which corresponds to the top dead center in terms of the position of a normal bicycle when pedaling, and also reduces the repeated impact and impact noise when the first slider tip side abutment portion S1f and the second slider tip side abutment portion S2f collide and abut.

[0188] In one embodiment of the compression coil spring N1, the difference in length between when unloaded and when compressed is large, and in the latter half of the return stroke of one pedal P due to depression of the other pedal P, the spring holding shaft N2 abuts against the second slider front block S21 to which the pedal P is attached, while providing an urging force that moves the entire second slider S2 as far as possible toward the tip of the swing arm A. Note that, as an alternative configuration, an elastic body made of, for example, rubber having elasticity can be used instead of the compression coil spring N1.

[0189] The movement of the second slider S2 may begin with a slight delay from the movement of the abutting first slider S1, but the movement will occur once the force that moves the second slider S2 is transmitted by the compression coil spring N1.

[0190] Subsequently, for example, when one of the pedals P is depressed with the foot (points F to H in Figures 11 and 12), the tensioned state is not released, so that in the first half of the depression, the first slider S1 is initially compressed by the depression force, and finally by the force of the first slider S1 moving against the second slider front block S21 which comes to a stop by abutting against the swing arm tip block A1, and the compression coil spring N1 further contracts, requiring additional operating force.

[0191] In the second half of the cycle, all contraction is released and the compression coil spring N1 expands to its original unloaded length, completing one cycle of expansion and contraction. However, the energy applied to pedal P to contract during this cycle is basically used to rotate the crank in the second half of the cycle, so no energy loss occurs in the crank operation of mechanism Z.

[0192] In this case, although not shown in the drawings, even if a solid tension member is attached instead of the elastic tension member N, the entire second slider S2 can be moved toward the tip of the swing arm A. Because the solid tension member does not contract, the second slider S2 and pedal P can be moved further toward the tip in the direction of the extension line passing through the fixed swing fulcrum axis AX and the crank axis CX1a by the length of the solid tension member that does not contract compared to when the elastic tension member N is not present.

[0193] Therefore, if this were to fail, the first precondition of the important requirement of Mechanism Z, namely, that in order to prevent the first slider rear end contact portion S1r from contacting the second slider rear end contact portion S2r before the crank rotation axis CX2a reaches approximately the lowest point PL of the crank circle used, it is necessary to increase the distance between the second slider front end contact portion S2f and the second slider rear end contact portion S2r by the amount of extra movement, and also that the oscillating arm A be extended towards the front end, and that the oscillating arm A is set to be kept to the minimum necessary length without being unnecessarily extended, would violate the second precondition of the important requirement of Mechanism Z, and therefore the fact that this precondition can be satisfied in this embodiment is another effect of the elastic tensioning function member.

[0194] On the other hand, if no angle offset is performed at the start of the depression (operation) stroke, depending on the depression direction, the narrow angle formed by the line passing through the line segment AX-CX1a shown in Figure 11 and the line passing through the line segment AX-PH is an upward elevation angle of α0 (in this case, 25 degrees), so that the compression coil spring N1 is contracted by the depression force in the opposite direction, and the second slider front block S21 to which the pedal P is attached and the pedal P will momentarily try to move backward toward the rear end on the swing arm A, but will immediately be pushed by the first slider S1 which moves in contact with the tip end and begin to move toward the tip end.

[0195] However, in this embodiment, as shown in FIG. 11, the fixed swing fulcrum axis A4 side of the extension line passing through the fixed swing fulcrum axis AX and the crank axis CX1a is rotated from the horizontal to the highest point with the crank axis CX1a as the center. The right angle Only β TiltSince it is attached to the frame F, the momentary backward movement of the pedal P is almost completely eliminated.

[0196] In addition, with this configuration, angled downwards Another effect of using the pedal shaft P10 tilted by β and attached to the frame F is that, as mentioned above, the lowest position of the pedal shaft P10 that is stepped on within the range of vertical movement of the person's leg is lowered slightly, while the highest position is lowered by the same amount, thereby suppressing the height. Specifically, when the pedal P starts to step on the pedal P, which is located at the tip end of the swing arm A, the position of the pedal P in this configuration is higher than the pedal position at the start of stepping on a normal crank circle, which is the pedal position at the top dead center T2d in Figure 11, and when the user needs to raise their leg higher when stepping on the pedal, and this repeated pedal operation becomes difficult, as shown in this figure The right angle Only β, tip side Downward It is tilted downwards and attached to the frame F. This significantly reduces the strain caused by repeated pedaling. [Industrial Applicability]

[0197] The pedal-shift crank rotation drive mechanism of the present invention can be used in a wide range of devices, including not only ordinary bicycles but also recumbent bicycles, tricycles for physically disabled people or for commercial use, fitness equipment, labor-saving devices and equipment, and other devices that apply external forces alternately to a pair of left and right crank arms attached to a crankshaft and have an output section that rotates integrally with the crankshaft. [Explanation of symbols]

[0198] 21a Swing support bearing stand 21b Insertion swing fulcrum axis 3 Tension swing cam 3R cam swing locking part 3R1 Cam Lock Pin 3R2 Second cam roller 31 Cam positioning stopper 4 bias spring 5 Output section A Swing Arm A1 Swing arm tip block A3 Guide bar A4 Fixed swing fulcrum axis CA crank arm CX1 crankshaft CX1a Crank shaft center CX2 crank pivot CX2a Crank rotation axis F Frame N Elastic tension member Nt tension contact member P Pedal PH Highest point PL lowest point PX Pedal shaft center S1 First slider S1c First cam roller S1f First slider tip contact area S1r Rear end contact point of first slider S2 Second slider S2f Contact point on tip of second slider S2r Rear end contact point of second slider S21 Block in front of the second slider Z pedal shift type crank rotation drive mechanism

Claims

1. a pair of left and right crank arms fixed to both ends of a crankshaft rotatably attached to a frame or the like, and operating with an operating phase angle difference of 180 degrees; a crank rotation shaft provided at the tip of each of the pair of left and right crank arms; a pair of left and right swing arms pivotally supported on a fixed swing fulcrum shaft fixedly disposed at a position away from the crankshaft by a distance greater than the length of the crank arm in the frame or the like; a pair of left and right first sliders that are rotatably supported on the crank rotating shaft and held by the swing arm, and are reciprocally movable along the longitudinal direction of the swing arm, and in which a first slider front end side abutment portion and a first slider rear end side abutment portion are held facing in opposite directions and move integrally in the longitudinal direction when the direction of the fixed swing fulcrum shaft in the longitudinal direction is the rear end side and the opposite direction is the front end side; a pair of second sliders, each held by the swing arm and reciprocating along the longitudinal direction of the swing arm, wherein a second slider front-end contact portion and a second slider rear-end contact portion, which move integrally in the longitudinal direction, are held facing each other while sandwiching the first slider at a predetermined interval, and the pair of left and right second sliders intermittently reciprocate within a movable range in the same direction as the reciprocating movement of the first slider due to contact or non-contact between the opposing first slider front-end contact portion and the second slider front-end contact portion, or contact or non-contact between the opposing first slider rear-end contact portion and the second slider rear-end contact portion; a pair of left and right pedals attached to a second slider front block configured to be located on the tip side of the first slider of the swing arm during the reciprocating movement of the first slider, and which alternately swing the left and right swing arms by alternately operating the second slider front block, and which, in conjunction with the swinging, apply a rotational force to the crank arm via the first slider while tracing a modified elliptical locus, and simultaneously apply a rotational force to the crank shaft; A pedal-shift type crank rotation drive mechanism that imparts rotational output to an output section that rotates integrally with the crankshaft.

2. a tension swing cam having a contact portion on the tip end side of the second slider, the tension cam being pivotally supported so as to be able to swing on a swing fulcrum shaft inserted into a bearing portion in a swing fulcrum bearing base attached to each of the second sliders held by the swing arm; a biasing spring attached to the swing fulcrum bearing base for swinging and rotating the tension swing cam in a predetermined direction; a cam positioning stopper provided on the second slider or the swing fulcrum bearing base for setting an upper limit position when the tension swing cam swings in the biasing direction of the biasing spring; a first cam roller having a contact portion on the tip side of the first slider attached and held by the first slider, for forming or releasing a tensioned state by contacting or not contacting the tension swing cam so that a predetermined distance maintaining state can be formed or released between the first slider and the second slider front block; 2. The pedal shift-type crank rotation drive mechanism according to claim 1, further comprising a cam swing / engagement portion integrally attached to the tip block of the swing arm, the second cam roller serving as a swing abutment and a swing lock for the tension swing cam so as to be movable and adjustable in the longitudinal direction, and a cam lock pin for swing locking.

3. an elastic tension member having a tip-side abutment portion attached to and held by either the first slider or the second slider, for transmitting a force that moves the second slider to the tip side in the longitudinal direction within a movable range while performing contact contraction in response to a change in the reduction amount of the gap between the first slider and the second slider front block; a tension contact member having a tip contact portion attached and held to either the second slider or the first slider; The pedal-shift type crank rotation drive mechanism according to claim 1 , comprising:

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