JP2003011878A - Elliptical locus crank - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide an elliptical locus crank allowing well-balanced, effective pedaling exercise and facilitating adjustment of inclination θ relative to a horizontal shaft. SOLUTION: A first crank 2 and a second crank 3 are connected to each other by a joint and a driving force transmission mechanism 4 for transmitting torque from the joint part to a center rotating shaft is supported against the surface or inside of the second crank 3. Further, the center rotating shaft of the second crank 3 is formed as a double inversion shaft mechanism 11, and normal rotation transmitted via the mechanism 4 is reversed by the mechanism 11 and output to the second crank 3 whereby the first crank 2 and the second crank 3 are doubly reversed to make the locus of the pedals 1 elliptical.

Description

Description: BACKGROUND OF THE INVENTION [0001] 1. Field of the Invention [0002] The present invention relates to a crank capable of drawing an elliptical trajectory.
The present invention relates to the elliptical locus crank including a first crank that rotates forward, a second crank that rotates reversely having the driving force transmission mechanism 4, and a counter-rotating shaft mechanism. 2. Description of the Related Art A conventional crank is a crank having a perfect circular locus constituted by a single crank and a single rotating shaft. Further, the pedal has an elliptical locus or a substantially semicircular arc formed by a combination of a pedal locus guide plate and a telescopic crank (for example, JP-A-2000-11).
6818, JP-A-2000-142534). [0003] Since the crank of a pedal type rotary motion device such as a bicycle or a bicycle ergometer has a true circular locus, it is difficult to perform pedal motion.
There is a limitation that the range of motion of the knees around the waist is narrow and the balance of exercise effects is poor. [0004] Therefore, when performing exercise, the load in the knee extension phase must be larger than the load in the knee flexion phase, and the exercise effect tends to be limited. In the knee extension phase, the hip flexor muscle group (quadriceps) and the biceps femoris extension muscle group (hamstrings) mainly work in the knee flexion phase. Muscle groups (quadriceps) are generally known to have relatively low endurance, and tend to be biased in fatigue when pedaling for a long time. The present invention achieves a well-balanced exercise effect by realizing an elliptical locus crank in which the inclination .theta. With respect to the horizontal axis can be easily adjusted, and expanding the range of motion of the knee centering on the waist in pedal motion. It is an object. [0007] In order to achieve the above object, in the crank of the present invention, the first crank 2 and the second crank 3 are connected by a joint, and from the joint to the rotation center axis. The driving force transmitting mechanism 4 for transmitting the rotational force is connected to the second crank 3
The rotation is supported on the surface or inside, and the rotation center axis is a double reversing shaft mechanism 11, and the forward rotation transmitted through the driving force transmission mechanism 7 on the rotation center axis side of the second crank 3 is used as the double reversing shaft mechanism. The first crank 2 and the second crank 3 are double-inverted by being inverted by 11 and output to the second crank 3 via the outer shaft gear 12, thereby making the trajectory of the pedal 1 elliptical. The counter-rotating shaft mechanism 11 has a gear ratio Z between the outer shaft gear 12 and the inner shaft gear 14 in order to make the angular speeds of the inner shaft 9 and the outer shaft 10 uniform and to reverse the rotation direction.
1: Z2 = 1: 1. At this time, in the driving force transmission mechanism 4 on the surface of or inside the second crank, the angular velocity ratio between the joint side 5 and the rotation center shaft side 7 is set to Va: Vo = 1: 1. And the ratio of the number of teeth of the gear on the rotation center shaft side 7 to Za: Zo
(In the case of a pulley, the ratio of the radius of the pulley ra: ro) = 1:
Let it be 1. [0011] In the above, the rotational angular velocity ratio between the joint side driving force transmitting mechanism 5 and the outer shaft gear 12 of the contra-rotating shaft mechanism is finally set to 1: 1 (for example, Za). : Zo or ra:
ro = 2: 1, Z1: Z2 = 1: 2, etc.), the same effect can be obtained. In the contra-rotating shaft mechanism, in order to make the inner shaft 9 a normal rotation shaft and the outer shaft 10 a reversing shaft, the rotation center shaft side 7 of the driving force transmission mechanism on the surface of or inside the second crank and the inner shaft 9 are used. Are fixed so that they rotate in the same direction, and the direction of rotation of the joint 1 side of the driving force transmission mechanism and the direction of rotation of the rotation center axis side 7 are the same, so that the direction of forward rotation of the pedal 1 It is transmitted to the inner shaft 9 of the mechanism. The outer shaft 10 of the contra-rotating shaft mechanism is fixed so as to rotate in the same direction as the second crank 3, and the space between the inner shaft 9 and the outer shaft 10 is sufficiently smooth by a ball bearing or other bearing mechanism 18. By doing so, the conversion of the rotation direction between forward rotation and reverse rotation is smoothed. The joint side 5 of the driving force transmission mechanism on the surface of or inside the second crank is firmly connected by a shaft 8 so as to rotate synchronously with the joint on the first crank side. As shown in FIG. 8, the first crank length L
By setting a to be longer than the second crank length Lb, an elliptical locus (major axis = La + Lb, minor axis = La−Lb)
And crank. Embodiments of the present invention will be described based on embodiments with reference to the drawings. FIG. 1 is a perspective development view of the present invention, and FIGS. 2 and 3 are a plan view of the same and a cross-sectional view of a contra-rotating shaft mechanism 11. The present invention basically comprises two cranks connected by a joint with a driving force transmission mechanism, the rotation center axis of which is a counter-rotating shaft mechanism, and the counter-rotating shaft mechanism is a bicycle or It is attached to the crankshaft of a pedal type rotary motion device such as a bicycle ergometer. In FIG. 1, the left and right first cranks 2a
2b, the second cranks 3a and 3b are attached to the crankshaft of a pedal-type rotary motion device such as a bicycle or a bicycle ergometer at an angle of θ with respect to the horizontal axis with a phase of 180 °. This is the shaft 8a, 8b of the joint between the left and right first cranks 2a, 2b and the second cranks 3a, 3b.
, The inclination θ can be easily adjusted. In FIGS. 1 and 2, a fixed clamp 16 covers an outer shaft gear 12, a contra-rotating intermediate gear group 13, and an inner shaft gear 14, and is attached to a main body 15 of a pedal type rotary motion device such as a bicycle or a bicycle ergometer. Firmly fixed. As a result, a reaction force for rotating the second crank 3 in the reverse direction by rotating the normal rotation transmitted from the pedal 1 in the reverse direction is taken. The main body 15 and the fixed clamp 16 are fixed via a vibration absorbing material 17. In FIG. 3, as shown in the arrangement example of the contra-rotating shaft mechanism 11, the forward rotation transmitted from the inner shaft gear 14 in the cross section AA is transmitted through the contra-rotating medium extending from the cross section AA to the cross section BB. The torque is transmitted by the gear group 13 so as to reverse the outer shaft gear 12. In order to smooth the forward / reverse conversion of the contra-rotating axis, the cross-section BB inner axis 9 and outer axis 10
A ball bearing 18 is provided between them. FIG. 4 shows an example in which the driving force transmitting mechanism on the second crank 3 is constituted by using the gears 51, 61, 71. FIG. 5 shows an example in which chain gears 52, 62 and 72 are used as the driving force transmission mechanism. FIG. 6 shows an example in which a pulley and belts 53, 63, 73 are used as the driving force transmission mechanism. In FIG. 7, (o) shows the trajectory of the knee and ankle during the running of a human. (A) shows a conventional circular locus crank, and (b) and (c) show the locus of the knee and ankle when the elliptical locus crank according to the present invention is rowed.
It can be seen that, in the present invention (b), the angle β indicating the movable range is wider than the movable range of the knee relative to the hip in (a). In FIG. 7, a section AB is a stepping-down phase,
Section BC is the kickback phase, and section CA is the attraction phase. In the attracting phase, the ankle is attracted by moving the knee ahead. In the normal running operation (o),
Smooth interlocking of the hip flexors (hamps) such as the left and right hip flexors and quadriceps in each phase is essential, but in (a) most of the movement is Muscle groups (quadriceps) are responsible,
Hip extension muscles such as biceps femoris (hamstrings) were limited to auxiliary movements. In (b), the action of the hip extension muscles (hamstrings) such as the gluteus maximus and biceps femoris muscles is brought closer to that of a normal walking or running motion by increasing the rotation angle α of the section CA. In FIG. 7 (c), an example in which the rotation angle α of the section CA is narrowed by mounting the installation angle θ downward with respect to the horizontal axis, and the exercise effect with a small load on the gluteus maximus muscle is exhibited. Show. FIG. 8 is a conceptual view of the motion of the elliptical locus crank according to the present invention. When the pedal 1 and the joint rotate in directions opposite to each other, the pedal has a long diameter La +
It is possible to draw an elliptical locus of Lb and the minor axis La-Lb. The present invention is configured as described above, and has the following effects. In the elliptical locus crank according to the present invention, by making the locus of the crank an elliptical locus, the motion of each muscle below the waist in the pedal-type exercise mode can be made closer to that of a normal walking motion or running motion. This has the effect of obtaining a balanced exercise effect. Further, the left and right cranks move with a phase of 180 °, thereby synchronizing the movements of the left and right muscles for sprinting and other running training and walking rehabilitation after illness, thereby providing a rhythmic feeling. Can be fed more quickly.

BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is a perspective developed view of an elliptical locus crank mechanism of the present invention. FIG. 2 is a plan view of FIG. FIG. 3 is a cross-sectional view taken along line AA and BB of the contra-rotating shaft mechanism shown in FIG. 2; 4 is a cross-sectional view of an example in which a gear is used as a driving force transmission mechanism in a second crank in a cross section taken along the line CC of FIG. 2; 5 is a sectional view of an example of a driving force transmission mechanism using a chain gear in FIG. 6 is a sectional view of an example of a driving force transmission mechanism using a pulley and a belt in FIG. FIG. 7 (o) is a running motion, (a) is a conventional perfect circular locus, and (b) and (c) are comparisons of a knee and ankle locus when the elliptical locus crank according to the present invention is rowed. FIG. FIG. 8 is a conceptual diagram of the motion of an elliptical locus crank. [Description of Signs] 1 Pedal 2 First crank 3 Second crank 4 Driving force transmission mechanisms 51, 52, 53 Joint part side driving force transmission mechanisms 61, 62, 63 Driving force transmission mediating parts 71, 72, 73 Rotation center axis Side driving force transmission mechanism 8 Joint shaft 9 Inner shaft 10 Outer shaft 11 Double reversing shaft mechanism 12 Outer shaft gear 13 Double reversing mediate gear group 14 Inner shaft gear 15 Pedal-type rotary motion device body 16 such as bicycle or bicycle ergometer Fixed clamp 17 Vibration absorber 18 Ball bearing

Claims (1)

(1) Two cranks connected by a joint. (B) A driving force transmission mechanism (4) provided on the second crank (3) for transmitting a rotational force from the joint to the second crank (3) rotation center shaft side. (C) A counter-rotating shaft mechanism (11) provided on the rotation center axis of the second crank (3). An elliptical locus crank configured as described above, wherein the pedal (1) draws an elliptical locus by reversing the first crank (2) and the second crank (3).