GB1563303A

GB1563303A - Rotary devices

Info

Publication number: GB1563303A
Application number: GB34315/76A
Authority: GB
Original assignee: Individual
Current assignee: Individual
Priority date: 1977-09-14
Filing date: 1977-09-14
Publication date: 1980-03-26

Description

(54) ROTARY DEVICES (71) I, RICHARD CRADDOCK HAYES, a British subject, of 65A Main Street, Kirby Muxloe, Leicestershire, do hereby declare the invention for which I pray that a patent may be granted to me, and the method by which it is to be performed, to be particularly described in and by the following statement: - The invention relates to rotary devices.

particularly rotary devices in which a pedal member partakes of movement in a path around a substantially horizontal axis, but maintains an unchanged attitude with respect to ground level, that is, does not become inverted at the top of its path.

The invention finds application, for example, in pedal-operated conveyances for physically handicapped persons, where the pedals must not be allowed to become inverted, even although the user's feet and angles may be paralysed or otherwise incapable of maintaining their position with even pressure upon the pedal.

The invention therefore provides in its broadest aspect a rotary device for use with a pedal-driven vehicle comprising a pedal member arranged for rotation about an axis, said axis passing through an outer end portion of a crank arm, an inner end portion of which is fixedly mounted upon a shaft rotatable in use with respect to a frame of the vehicle, a first sprocket wheel mounted upon the shaft to allow rotation of the shaft relative thereto, means for maintaining the first sprocket wheel stationary with respect to the shaft, a second sprocket wheel fixedly mounted on said member for coaxial rotation therewith and connection means connecting the two sprocket wheels, the construction and arrangement being such that during each rotation of the shaft and the crank arm through 360 , the pedal member partakes of a circular movement through 360" with respect to the outer end portion of the crank arm, as a result of the connection between the two sprocket wheels.

It will be understood that the term "sprocket wheel" is intended to cover wheels suitable for use with drive belts where these comprise the connecting means.

The device of the invention may be applied to a bicycle, tricycle or other similar pedal-driven vehicle. The arrangement is such that a conventional bicycle may be converted into a bicycle suitable for use by handicapped children. Such a conversion is relatively unobtrusive and the mobility afforded to the children is of great psychological value.

Thus, the pedal of a child's bicycle may be maintained in a horizontal position during its movement in a circular path.

However, where the cycle is for use by, for example, spastic children, account must be taken of deformation of muscle and ligament which may result in the foot becoming extended and therefore requiring an obliquely positioned pedal. It may be beneficial therefore to the patient gradually to restore the Achilles tendon, which has become foreshortened, to its correct length.

The invention provides, therefore, in its preferred embodiment a rotary device as hereinabove described in which is provided adjustment means whereby the angle of the pedal may be adjusted as desired, but when in use is maintained at that desired angle.

Thus, a number of small adjustments to the pedal angle may be made over a period of time, gradually to bring the oblique angle nearer to the horizontal.

The invention will now be described, by way of example, with reference to the accompanying drawings in which: Figure 1 is a side view of a device according to a first embodiment of the invention; Figure 2 is a front view of the device shown in Figure 1; Figure 3 is a view of a pedal member for use with the device shown in Figure 1; Figure 4 is a side view of a device according to a preferred embodiment of the invention; Figure 5 is a front view of a portion of the device shown in Figure 4; and Figure 6 is a diagrammatic illustration of the adjustment achieved in the device shown in Figure 4.

In Figures 1 to 3, a frame portion 2 of a child's bicycle supports a main bearing 4 which rotatably receives a shaft 6 upon which is fixedly mounted a main drive wheel 8 of the bicycle around which travels a conventional bicycle chain (not shown).

Also mounted on the shaft 6 outboard of the wheel 8 is a first sprocket wheel 10, which is held stationary with respect to the rotatable shaft 6 by means of a tie rod 12, linked to the frame 2. The rod 12 is shaped to lie clear of the wheel 8 and the chain (not shown).

An inner end of a crank arm 14 is mounted on the shaft 6 and fixedly secured by a pin 16. Mounted for rotation about an axis passing through the outer end of the crank arm 14 is a rod 18. One end of the rod 18 and is provided with a second sprocket wheel 20 fixedly secured thereto.

In the present example, the two sprocket wheels, which are identical in diameter and tooth pitch, are linked by a chain 22, but it will be understood that a drive belt may be used, or a gear chain including an odd number of idler gear wheels.

A pedal 24 is fixedly secured to the second, outer end of the rod 18. This pedal comprises a platform portion 26 and a vertical support portion 28, which also acts as a shield for the rider's foot. In the present example, the upper surface of the platform, which is made of metal, is contoured, having an outwardly extending groove 30 into which is fitted a tubular plastics member, indicated in dotted lines at 32, which is secured to the bottom of the rider's footwear 34. This helps to maintain the foot in position on the pedal, but in the event of the rider falling off, readily releases the foot to prevent injury.

In use, the rider will press downwardly on alternate pedals as in a conventional bicycle. This causes the crank arm 14 to rotate with the shaft 6 to drive the wheel 8. However, the sprocket wheel 10 does not rotate since it is held stationary by the rod 12. Therefore the movement of the pedal in its circular path causes the chain 22 to progress around the sprocket teeth. In doing so, the chain causes the second sprocket wheel 20 to rotate about the axis of the rod 18, and thus maintain the initial horizontal attitude of the pedal 24 by causing it to rotate through 360" with respect to the crank member during each complete rotation of the crank member.

In Figures 4 to 6 the construction of the device is similar to that shown in Figures 1 to 3 and like parts are shown with like numerical references, but with the addition of a dash for example "2"'.

The tie rod 12' is secured at one end thereof to the first sprocket wheel 10', in a similar manner to the rod 12 and the wheel 10 above-mentioned but this time the other end is received in an arcuate slot 42 of a plate 40 secured to the main bearing housing 4'. A nut 44 secures the rod 12' in any chosen angle radially of the shaft 6' within the limits of the slot 42. The angle will determine the rest position of the first sprocket wheel 10' on the shaft 6', and thus the angle of the pedal 24' with respect to the horizontaL The pedal includes a platform portion 26', which in the present example is of metal.

Thus adjustment of the tie rod 12' will govern the angle at which the pedal operates, as shown diagrammaticaly in Figure 6.

Various modifications may be made within the scope of the invention.

WHAT I CLAIM IS: - 1. A rotary device for use with a pedaldriven vehicle comprising a pedal member arranged for rotation about an axis, said axis passing through an outer end portion of a crank arm, an inner end portion of which is fixedly mounted upon a shaft rotatable in use with respect to a frame of the vehicle, a first sprocket wheel mounted upon the shaft to allow rotation of the shaft relative thereto, means for maintaining the first sprocket wheel stationary with respect to the shaft, a second sprocket wheel fixedly mounted on said member for coaxial rotation therewith and connection means connecting the two sprocket wheels, the construction and arrangement being such that during each rotation of the shaft and the crank arm through 360 , the pedal member partakes of a circular movement through 360" with respect to the outer end portion of the crank arm, as a result of the connection between the two sprocket wheels.

2. A rotary device as claimed in claim 1

**WARNING** end of DESC field may overlap start of CLMS **.

Claims

**WARNING** start of CLMS field may overlap end of DESC **. Figure 2 is a front view of the device shown in Figure 1; Figure 3 is a view of a pedal member for use with the device shown in Figure 1; Figure 4 is a side view of a device according to a preferred embodiment of the invention; Figure 5 is a front view of a portion of the device shown in Figure 4; and Figure 6 is a diagrammatic illustration of the adjustment achieved in the device shown in Figure 4. In Figures 1 to 3, a frame portion 2 of a child's bicycle supports a main bearing 4 which rotatably receives a shaft 6 upon which is fixedly mounted a main drive wheel 8 of the bicycle around which travels a conventional bicycle chain (not shown). Also mounted on the shaft 6 outboard of the wheel 8 is a first sprocket wheel 10, which is held stationary with respect to the rotatable shaft 6 by means of a tie rod 12, linked to the frame 2. The rod 12 is shaped to lie clear of the wheel 8 and the chain (not shown). An inner end of a crank arm 14 is mounted on the shaft 6 and fixedly secured by a pin 16. Mounted for rotation about an axis passing through the outer end of the crank arm 14 is a rod 18. One end of the rod 18 and is provided with a second sprocket wheel 20 fixedly secured thereto. In the present example, the two sprocket wheels, which are identical in diameter and tooth pitch, are linked by a chain 22, but it will be understood that a drive belt may be used, or a gear chain including an odd number of idler gear wheels. A pedal 24 is fixedly secured to the second, outer end of the rod 18. This pedal comprises a platform portion 26 and a vertical support portion 28, which also acts as a shield for the rider's foot. In the present example, the upper surface of the platform, which is made of metal, is contoured, having an outwardly extending groove 30 into which is fitted a tubular plastics member, indicated in dotted lines at 32, which is secured to the bottom of the rider's footwear 34. This helps to maintain the foot in position on the pedal, but in the event of the rider falling off, readily releases the foot to prevent injury. In use, the rider will press downwardly on alternate pedals as in a conventional bicycle. This causes the crank arm 14 to rotate with the shaft 6 to drive the wheel 8. However, the sprocket wheel 10 does not rotate since it is held stationary by the rod 12. Therefore the movement of the pedal in its circular path causes the chain 22 to progress around the sprocket teeth. In doing so, the chain causes the second sprocket wheel 20 to rotate about the axis of the rod 18, and thus maintain the initial horizontal attitude of the pedal 24 by causing it to rotate through 360" with respect to the crank member during each complete rotation of the crank member. In Figures 4 to 6 the construction of the device is similar to that shown in Figures 1 to 3 and like parts are shown with like numerical references, but with the addition of a dash for example "2"'. The tie rod 12' is secured at one end thereof to the first sprocket wheel 10', in a similar manner to the rod 12 and the wheel 10 above-mentioned but this time the other end is received in an arcuate slot 42 of a plate 40 secured to the main bearing housing 4'. A nut 44 secures the rod 12' in any chosen angle radially of the shaft 6' within the limits of the slot 42. The angle will determine the rest position of the first sprocket wheel 10' on the shaft 6', and thus the angle of the pedal 24' with respect to the horizontaL The pedal includes a platform portion 26', which in the present example is of metal. Thus adjustment of the tie rod 12' will govern the angle at which the pedal operates, as shown diagrammaticaly in Figure 6. Various modifications may be made within the scope of the invention. WHAT I CLAIM IS: -

1. A rotary device for use with a pedaldriven vehicle comprising a pedal member arranged for rotation about an axis, said axis passing through an outer end portion of a crank arm, an inner end portion of which is fixedly mounted upon a shaft rotatable in use with respect to a frame of the vehicle, a first sprocket wheel mounted upon the shaft to allow rotation of the shaft relative thereto, means for maintaining the first sprocket wheel stationary with respect to the shaft, a second sprocket wheel fixedly mounted on said member for coaxial rotation therewith and connection means connecting the two sprocket wheels, the construction and arrangement being such that during each rotation of the shaft and the crank arm through 360 , the pedal member partakes of a circular movement through 360" with respect to the outer end portion of the crank arm, as a result of the connection between the two sprocket wheels.

2. A rotary device as claimed in claim 1

wherein the pedal member remains horizontal during said circular movement.

3. A rotary device as claimed in claim 1 wherein adjustments are provided whereby the angle of the pedal member to the horizontal is adjustable as desired and, in use, is maintained at that desired angle.

4. A rotary device as hereinbefore described with reference to and as illustrated in Figures 1 to 3 of the accompanying drawings.

5. A rotary device as hereinbefore described with reference to and as illustrated in Figures 4 to 6 of the accompanying drawings.