US20060019802A1 - Removable crank arm for exercise cycle - Google Patents

Abstract

A pedal for an exercise bicycle which can be located at various distances from the axis of rotation of a crank arm to which the pedal is attached. The crank arm is removable and is connected to the vertical portion of the pedal arm of the exercise bicycle. The crank arm rotates about the axis of rotation of the pedal arm and a pedal is mounted to the crank arm at a distance which is adjustable depending upon the degree of movement of the limb of a user. The pedal arm need not be removed from the exercise bicycle.

Description

• This invention relates to a removable crank arm for an exercise bicycle and, more particularly, to a removable crank arm for an exercise bicycle which allows adjustable mounting of a pedal to the crank arm in order to provide greater or lesser movement of the limbs of a user.
BACKGROUND OF THE INVENTION
• Exercise bicycles are, of course, well known. They are provided usually for fitness or training purposes. Because the pedal on which the user rests his foot moves in a circular path, impact blows to the user are avoided which is desirable to prevent aches and sprains to the joints and muscles. Such exercise bicycles are particularly useful for the elderly or for rehabilitation purposes.
• Arthritic users are restricted in movement and the more prevalent the arthritis in the user, the more restrictive is the movement. While exercise is known to be beneficial for sufferers of arthritis, and while the movement of the pedals of an exercise bicycle is particularly advantageous because of the absence of shocks and impact to the user, the range of movement of the legs and knees of a user who is suffering from arthritis may not be sufficient to completely rotate the pedal arm to which the pedals are attached. It would be desirable to adjust the motion path of the pedals in order to increase or decrease the range of motion to be performed by the user so as to adapt to the movement of the individual user.
• Various apparatuses have been designed to deal with the requirement for an adjustable path of the pedals. U.S. Pat. No. 5,316,532 (Butler) discloses an aquatic exercise cycle with a disc which allows incrementally spaced means to secure the legs of a user. U.S. Pat. No. 4,509,742 (Cones) teaches a hydraulic exercise cycle with a flywheel which allows incremental adjustment of the pedal assembly to the flywheel thereby allowing variable load resistance. Canadian application 2,235,465 (Saringer et al) teaches a flywheel to which resistance is adjustable by way of a control circuit. And Butterworth U.S. Pat. No. 6,589,139 teaches a primary and a secondary crank which allow or prohibit relative movement therebetween and which require tht the pedal arm be attached to the axis of the pedal arm assembly with a removable bolt and an additional member.
• The prior art, however, does not teach an exercise bicycle which may be easily adjusted or modified to allow a reduced path of motion of a pedal for users who may lack the ability to participate in the full range of motion such as those arthritic users aforementioned.
SUMMARY OF THE INVENTION
• According to one aspect of the invention, there is provided a removable crank arm for an exercise bicycle having a pedal arm with a pedal arm axis of rotation and having a first generally horizontal axle section and a second generally vertically extending pedal arm section, said removable crank arm comprising attachment means for attachment of said removable crank arm to said second generally vertically extending pedal arm section of said pedal arm of said exercise bicycle, said removable crank arm being rotatable about a crank arm axis and being operably connected to said pedal arm and being generally rotatable about said axis of rotation of said pedal arm, said removable crank arm further comprising a pedal operably mounted to said crank arm at at least one distance from said crank arm axis, said rotatable pedal rotating about a pedal axis of rotation relative to said crank arm, said removfable crank arm being connected to said pedal arm at a location other than said axis of rotation of said pedal arm.
• According to a further aspect of the invention, there is provided a method of moving a pedal connected to a crank arm at a predetermined distance from the axis of rotation of said crank arm mounted on an exercise bicycle, said method comprising removing a pedal from a pedal arm which rotates about a pedal arm axis of said exercise bicycle, said pedal arm having a first generally horizontal axle section and a second generally vertically extending pedal arm section, mounting said crank arm on said second generally vertically extending pedal arm section by connecting said crank arm to said second generally vertically extending pedal arm section of said pedal arm such that said crank arm rotates about the axis of rotation of said pedal arm and mounting a rotatable pedal on said crank arm which pedal is adapted to be connected at at least two predetermined distances from the axis of rotation of said crank arm, said rotatable pedal rotating about a pedal axis of rotation, said crank arm being mounted to said pedal arm at a location other than said axis of rotation of said pedal arm.
BRIEF DESCRIPTION OF THE SEVERAL VIEWS OF THE DRAWINGS
• Specific embodiments of the invention will now be described, by way of example only, with the use of drawings in which:
• FIG. 1 is a diagrammatic isometric view of the exercise bicycle with the rotating crank arm illustrated in operative position according to the invention;
• FIG. 2 is a rear view of the inside of the crank arm particularly illustrating the installed position of the crank arm on the pedal arm of the exercise bicycle according to the invention;
• FIGS. 3A and 3B are diagrammatic side and plan view of wedge clamps used to secure the crank arm to the pedal arm of the exercise bicycle according to the invention;
• FIG. 4 is an outside diagrammatic view of the flywheel illustrating the pedal attachment holes according to the invention and the pedal arm being shown in broken lines;
• FIG. 5 illustrates the attachment shaft used to connect the pedal to the crank arm according to the invention;
• FIGS. 6A and 6B are diagrammatic side and inside views of the crank arm, respectively, illustrating a further embodiment of the attachment of the crank arm to the pedal assembly; and
• FIG. 7 is an outside view of the crank arm illustrating a further attachment technique of the crank arm to the pedal arm.
DESCRIPTION OF SPECIFIC EMBODIMENT
• Referring now to the drawings, an exercise bicycle according to the invention is generally illustrated at100 inFIG. 1. It is of the type usually used in recreational and fitness centers and includes aseat101 for a user, a read outdevice102 and aframe103 sed to enclose and support the movement of a rotatingpedal104 which is attached to a rotatingcrank arm110.
• Rotatingcrank arm110 is connected to a pedal arm111 (FIG. 2) in a manner to be described and rotates about acrank arm axis112. The pedal arm111 comprises two well defined portions, namely a first generally horizontalaxle section portion200 and a second generally vertically extending pedal arm section115 (FIG. 6B). Thecrank arm110 includes a plurality ofattachment holes113 which allow thepedal104 to be connected to thecrank arm110 at various distances from theaxis112. Thepedal104 may have aheel cup114 and atoe strap120 which will allow the foot or shoe of the user to be securely held in place when using thepedal104.
• Referring now toFIG. 2, the inside surface of thecrank arm110 is illustrated as being mounted on the generally vertically extendingpedal arm portion115 of the pedal arm111 of theexercise bicycle100. The pedal of the pedal arm111 is removed and thecrank arm110 is then mounted onto the pedal arm111 by way of a groove121 (also shown inFIG. 3A) which is machined in thecrank arm110. Wedge assemblies122 (FIGS. 3A and 3B) are provided to clamp thecrank arm110 onto the pedal arm111 such that theaxis112 of thecrank arm110 is generally coincident with the axis of the pedal arm111. Setscrews123,124 may be used to attach thewedge clamp assemblies122 to thecrank arm110 and also to allow adjustable movement of thewedge clamp assemblies122 when thecrank arm110 has reached its proper position on the pedal arm111 so that thecrank arm110 is securely held on the pedal arm111.
OPERATION
• In operation, the pedal (not illustrated) of the original pedal arm111 of theexercise bicycle100 will be removed and thewedge claim assemblies122 will be opened to allow entry of the pedal arm111 of the exercise bicycle into the grove121 of thecrank arm110 whichcrank arm110 is manipulated into position on the pedal arm111.
• Thecrank arm110 will be positioned on the pedal arm111 so that the axis ofrotation112 of thecrank arm110 is coincident with the axis of rotation of the pedal arm111 when under normal operation with theexercise bicycle100. When that position is reached, theset screws123 will be rotated by, for example, a hex key (not illustrated) until thecrank arm100 is securely attached to the pedal arm111. Of course, while the attachment of only onecrank arm110 has been described, it will be appreciated that the same operation will occur on the side of theexercise bicycle100 which is opposed.
• Following the attachment of thecrank arm110 to the pedal arm111 of theexercise bicycle100 on both sides, thepedal104 will be attached. Pedal104 itself rotates about a pin130 (FIG. 5) which has a threadedend131 and ahead132 which maintains thepedal104 on thepin130. Theholes113 are threaded and complementary to the threads onpin130 so that thepin130 and attachedpedal104 can be attached to whatever hole133 is deemed appropriate for the user. For example, if the degree of arthritis suffered by he user is high or if injury rehabilitation dictates an initial and very small movement of the limb of the user, theholes113 closest to the axis ofrotation112 of thecrank arm110 may be dictated for pedal and pin attachment. Conversely, as the degree of flexibility and limb movement of the user increases, thepin130 and attachedpedal104 can be threadedly attached to ahole113 further removed from the axis ofrotation112 of thecrank arm112.
• The user will then assume the usual position on theexercise bicycle100 and with his feet in thepedal104, he will rotate thecrank arm110 thereby obtaining exercise and proper movement of the intended limb.
• Thecrank arm110 may be attached to the pedal arm111 is a variety of different ways and a further method of attachment is illustrated inFIGS. 6A and 6B. In this attachment technique, thehorizontal arm200 of the pedal arm111 is positioned in acradle201 which is mounted to thecrank arm110. Thiscradle201 may be movable between attachment holes or by way of a sliding movement in an oblong hole such as thathole202 such that thecrank arm110 rotates about the axis of rotation of the pedal arm111. Following the proper positioning of the pedal arm111 andpedal arm cradle201, thehole203 of the pedal arm111 to which the pedal is originally attached is aligned with ahole202 in thecrank arm110 and a bolt orpin204 secures the pedal arm111 to thecrank arm110. Thereafter, thepedal104 is connected on one of the series ofholes113 which are machined into the outside surface of thecrank arm110.
• Yet a further attachment technique illustrated inFIG. 7. In that embodiment, the pedal arm111 is connected to the wedge clamps122 as already described in association with the embodiment ofFIGS. 2 and 3. However, thecrank arm110 has a countersunkhole300 drilled through its thickness and a complementaryflat head bolt301 in positioned in thehole300 and extends through the join the pedal arm111 at the hole in the pedal arm111 previously occupied by thepedal104. Thus, thecrank arm110 will rotate with the pedal arm111 in precisely the same manner as previously described with the pedal104 being connected to any one of the machined holes302 depending on the extent of movement ability possessed or desired by the user.
• Many further embodiments will readily occur to those skilled in the art to which the invention relates and the particular embodiments described are given by way of example only and are not intended as limiting the scope of the invention as defined in accordance with the accompanying claims.

Claims (10)

1. A removable crank arm for an exercise bicycle having a pedal arm with a pedal arm axis of rotation and having a first generally horizontal axle section and a second generally vertically extending pedal arm section, said removable crank arm comprising attachment means for attachment of said removable crank arm to said second generally vertically extending pedal arm section of said pedal arm of said exercise bicycle, said removable crank arm being rotatable about a crank arm axis and being operably connected to said pedal arm and being generally rotatable about said axis of rotation of said pedal arm, said removable crank arm further comprising a pedal operably mounted to said crank arm at at least one distance from said crank arm axis, said rotatable pedal rotating about a pedal axis of rotation relative to said crank arm, said removfable crank arm being connected to said pedal arm at a location other than said axis of rotation of said pedal arm.

2. A removable crank arm as inclaim 1 and further comprising at least two attachment points for said pedal of said crank arm, said at least two attachment points being located a different distances from said axis of rotation of said crank arm.

3. A removable crank arm as inclaim 2 wherein said crank arm is attached to said second generally vertically extending pedal arm section with wedge assemblies mounted on said crank arm.

4. A removable crank arm as inclaim 2 wherein said crank arm is attached to said second generally vertically extending pedal arm section of said pedal arm by use of bolts.

5. A removable crank arm as inclaim 4 wherein said crank arm is provided with a cradle to allow entry of said first generally horizontal axle section of said pedal arm.

6. A removable crank arm as inclaim 1 wherein said pedal is connected to said crank arm with a threaded bolt.

7. A removable crank arm as inclaim 1 and further comprising a plurality of holes in said crank arm to allow attachment of said pedal to said crank arm at one of said holes.

8. A method of moving a pedal connected to a crank arm at a predetermined distance from the axis of rotation of said crank arm mounted on an exercise bicycle, said method comprising removing a pedal from a pedal arm which rotates about a pedal arm axis of said exercise bicycle, said pedal arm having a first generally horizontal axle section and a second generally vertically extending pedal arm section, mounting said crank arm on said second generally vertically extending pedal arm section by connecting said crank arm to said second generally vertically extending pedal arm section of said pedal arm such that said crank arm rotates about the axis of rotation of said pedal arm and mounting a rotatable pedal on said crank arm which pedal is adapted to be connected at at least two predetermined distances from the axis of rotation of said crank arm, said rotatable pedal rotating about a pedal axis of rotation, said crank arm being mounted to said pedal arm at a location other than said axis of rotation of said pedal arm.

9. Method as inclaim 8 wherein a pedal is removed from said pedal arm and said crank arm is connected to said second generally vertically extending pedal arm section of said pedal arm using a wedge assembly.

10. Method as inclaim 8 wherein said pedal is removed from said pedal arm and said crank arm is connected to said second generally vertically extending pedal arm section of said pedal arm using bolts.

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