U.S. patent application number 11/882630 was filed with the patent office on 2008-08-07 for drive for a pedal powered kayak.
This patent application is currently assigned to WAVEWALKER INC. Invention is credited to Harry Howard, David Wilcoxen.
Application Number | 20080188146 11/882630 |
Document ID | / |
Family ID | 39676571 |
Filed Date | 2008-08-07 |
United States Patent
Application |
20080188146 |
Kind Code |
A1 |
Howard; Harry ; et
al. |
August 7, 2008 |
Drive for a pedal powered kayak
Abstract
A pedal powered boat having a drive assembly including an
eccentric idler provides adjustment or tension for a chain used as
part of the drive assembly to power the boat. A crankshaft assembly
and a bevel gear assembly are uniquely combined to produce a smooth
pedaling operation for the user. The bevel gear assembly is
operable to change the direction of rotation 90 degrees and
increasing the speed three times for a net overdrive of six times
for creating the speed necessary for a propeller drive.
Inventors: |
Howard; Harry; (Bellingham,
WA) ; Wilcoxen; David; (Everson, WA) |
Correspondence
Address: |
JAMES R. THEIN
2231 CRYSTAL DRIVE, SUITE 105
ARLINGTON
VA
22202
US
|
Assignee: |
WAVEWALKER INC
|
Family ID: |
39676571 |
Appl. No.: |
11/882630 |
Filed: |
August 3, 2007 |
Related U.S. Patent Documents
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Application
Number |
Filing Date |
Patent Number |
|
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60835426 |
Aug 4, 2006 |
|
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Current U.S.
Class: |
440/30 |
Current CPC
Class: |
B63H 16/20 20130101 |
Class at
Publication: |
440/30 |
International
Class: |
B63H 16/20 20060101
B63H016/20 |
Claims
1. A pedal powered boat having a drive assembly, said drive
assembly comprising, a crankshaft assembly, said crank shaft
assembly having crank arms and crank pedals, a chain, said chain
connected to a bevel gear assembly and to said crankshaft assembly,
said chain tensioned by an eccentric idler, said bevel gear
assembly connected to a cassette assembly, said bevel gear assembly
operable to change the direction of rotation 90 degrees and
increasing the speed three times for a net overdrive of six times
for creating the speed necessary for a propeller drive.
2. The drive assembly as recited in claim 1, said drive assembly
further comprising an injection-molded glass reinforced urethane
housing.
3. The drive assembly as recited in claim 1, said drive assembly
further comprising a drive housing with a cover connected by a
grooved glue joint entirely encircling said drive housing said glue
joint having standoff points around its perimeter for adjustments
in size between said housings.
4. The drive assembly as recited in claim 1, said drive assembly
further comprising three grooves in housings to allow incremental
rotations of said eccentric idler of 2.5 degrees.
5. The drive assembly as recited in claim 1, said drive assembly
further comprising a cassette assembly, said cassette assembly held
in place in a prop shaft cassette by a prop-nut, said prop-nut
threaded onto female threads in said prop-shaft cassette.
6. The drive assembly as recited in claim 1, said drive assembly
further comprising a prop-shaft cassette, said prop-shaft cassette
including a lip, said lip forcing said/prop-shaft assembly inward
to adjust a gear lash.
7. A pedal powered boat having a drive assembly, said drive
assembly comprising, a crankshaft assembly, said crank shaft
assembly having crank arms and crank pedals, a chain, said chain
connected to a bevel gear assembly and to said crankshaft assembly,
said bevel gear assembly connected to a cassette assembly, said
bevel gear assembly operable to change the direction of rotation 90
degrees and increasing the speed three times for a net overdrive of
six times for creating the speed necessary for a propeller drive,
and eccentric means for tensioning said chain, said eccentric means
including a chain idler sprocket and a bearing mounted between two
eccentric housings, said idler and said bearing are mounted on a
shaft said shaft having an center eccentric with a center of said
eccentric housings which rotate in openings, said rotation causing
said idler said bearing to move in and out to tension said
chain.
8. The drive assembly as recited in claim 7, said drive assembly
further comprising an injection-molded glass reinforced urethane
housing.
9. The drive assembly as recited in claim 7, said drive assembly
further comprising a drive housing with a cover connected by a
grooved glue joint entirely encircling said drive housing said glue
joint having standoff points around its perimeter for adjustments
in size between said housings.
10. The drive assembly as recited in claim 7, said drive assembly
further comprising three grooves in housings to allow incremental
rotations of said eccentric idler of 2.5 degrees.
11. The drive assembly as recited in claim 7, said drive assembly
further comprising a cassette assembly, said cassette assembly held
in place in a prop shaft cassette by a prop-nut, said prop-nut
threaded onto female threads in said prop-shaft cassette.
13. The drive assembly as recited in claim 7, said drive assembly
further comprising a prop-shaft cassette, said prop-shaft cassette
including a lip, said lip forcing said/prop-shaft assembly inward
to adjust a gear lash.
14. A pedal powered boat having a drive assembly, said drive
assembly comprising, a crankshaft assembly, said crank shaft
assembly having crank arms and crank pedals, a chain, said chain
connected to a bevel gear assembly and to said crankshaft assembly,
said bevel gear assembly connected to a cassette assembly, and a
eccentric means for tensioning said chain, said eccentric means
including a chain idler sprocket and a chain idler bearing mounted
between two eccentric housings, said idler and said bearing are
mounted on a shaft said shaft having an center eccentric with a
center of said eccentric housings which rotate in openings, said
rotation causing said idler said bearing to move in and out to
tension said chain.
15. The drive assembly as recited in claim 14, said drive assembly
further comprising an injection-molded glass reinforced urethane
housing.
16. The drive assembly as recited in claim 14, said drive assembly
further comprising a drive housing with a cover connected by a
grooved glue joint entirely encircling said drive housing said glue
joint having standoff points around its perimeter for adjustments
in size between said housings.
17. The drive assembly as recited in claim 14, said drive assembly
further comprising three grooves in housings to allow incremental
rotations of said eccentric idler of 2.5 degrees.
18. The drive assembly as recited in claim 14, said drive assembly
further comprising a cassette assembly, said cassette assembly held
in place in a prop shaft cassette by a prop-nut, said prop-nut
threaded onto female threads in said prop-shaft cassette.
19. The drive assembly as recited in claim 14, said drive assembly
further comprising a prop-shaft cassette, said prop-shaft cassette
including a lip, said lip forcing said/prop-shaft assembly inward
to adjust a gear lash.
Description
BACKGROUND OF THE INVENTION
[0001] 1. Field of the Invention
[0002] This invention relates to watercraft, and more particularly
to a drive assembly for an occupant-powered watercraft.
[0003] 2. Description of the Related Art
[0004] Pedal-type watercraft have never been popular due the weight
and maintenance of the gearing assembly. However, in recent years,
popularity has increased due at least in part to participants
active in biking, swimming, canoeing and other types of water
sports for individuals who are the health-conscious. With new
recent legislation restricting the use of motorized watercraft such
as jet skis due to safety concerns, water bike have increased in
popularity. In addition, the pedal powered water vehicles have
great advantages for use in hunting and fishing as they run silent
and can be taken into rocky hazardous areas with the fear of
damaging the motor. Pedal powered watercraft can travel greater
distances faster than oar powered craft and can be quickly
stabilized without dropping a rod or a gun to pick up an oar to
maintain stability of the boat.
[0005] One type of pedal-powered watercraft is disclosed in U.S.
Pat. No. 4,795,381 issued to Willems on Jan. 3, 1989. The
watercraft disclosed by Willems includes a floating body upon which
a pedal assembly and recumbent seat are mounted. The seat can be
adjusted toward or away from the pedal assembly to accommodate
different sizes of users. An endless drive chain, reduction
gearing, and a drive shaft connect the pedal assembly to a
propeller. In one embodiment of this patent, the propeller and
drive shaft extend downwardly and rearwardly from the floating
body. A tandem seating arrangement is also shown.
[0006] Beres U.S. Pat. No. 5,460,551 discloses a pedal-powered
watercraft shaped as a kayak with an integrally molded seat. A
pedal assembly is connected to a propeller through a transmission
and drive shaft arrangement. A front storage compartment as well as
a rear storage compartment are provided.
[0007] U.S. Pat. No. 6,210,242 further discloses a pedal powered
watercraft made with a unitary hull. The hull is made of a pair of
spaced sponsons located on each side of the hull. Each sponson has
a front wall that meets the water head on but becomes unstable as
the water enters the keel at the tip of the boat causing a rocking
motion. The rocking is caused during movement of the watercraft
when water enters into the tunnel at the bow portion and exit the
tunnel at the stern portion. Although the propeller is retractable,
a large portion remains in the water during storage in the tunnel
area.
[0008] Pedal-powered watercraft of the past also fail to present a
hull design for traveling in rough water. Most hulls for these
types of watercraft are designed for a one time user to get on and
off the boat without falling into the water from the boat tipping.
Such uses are in marinas or small ponds where the water is
generally calm and the boat does not have to generate speed for
long distance travel. There is a need in the recreational sports
field for a pedal powered watercraft which is designed for high
speed but stable enough for maneuvering in water around rocks and
debris in the water. There is a greater need for a pedal powered
kayak with a drive assembly and hull which is simple to operate and
designed for speed.
SUMMARY OF THE INVENTION
[0009] An object of the present invention is to provide a
watercraft with an eccrentric idler for a drive assembly of a
kayak.
[0010] Another object of the present invention is to provide a
novel drive assembly for a pedal powered kayak.
[0011] Another object of the present invention is to provide a
watercraft with a crankshaft assembly for a drive assembly for a
pedal powered kayak.
[0012] It is still another object of the present invention to
provide a pedal-powered watercraft having a bevel gear
assembly.
[0013] It is a further object of the invention to provide a
pedal-powered watercraft which has a cassette assembly for a drive
assembly of a pedal powered watercraft.
[0014] It is an even further object of the invention to provide a
pedal-powered watercraft with a means for tensioning the chain
during operation of a pedal powered kayak.
[0015] According to the invention, a pedal powered kayak is
presented which has Other objects and advantages of the invention
will become apparent upon reading the following detailed
description and appended claims, and upon reference to the
accompanying drawings.
[0016] A pedal powered boat having a drive assembly including an
eccentric idler provides a tension and adjustment during operation
of the pedal drive. A crankshaft assembly and a bevel gear assembly
are uniquely combine to produce a smooth pedaling operation for the
user. The bevel gear assembly is operable to change the direction
of rotation 90 degrees and increasing the speed three times for a
net overdrive of six times for creating the speed necessary for a
propeller drive.
BRIEF DESCRIPTION OF THE DRAWINGS
[0017] The preferred embodiments of the present invention will
hereinafter be described in conjunction with the appended drawings,
wherein like designations denote like elements, and wherein:
[0018] FIG. 1 is a perspective view of a pedal-powered watercraft
according to the invention;
[0019] FIG. 2 is a plan view of a second half section of the drive
assembly of the present invention.
[0020] FIG. 2a is a plan view of a second half section of the drive
assembly of the present invention.
[0021] FIG. 3 is an exploded view of the drive assembly of the
present invention.
[0022] FIG. 4 is a side view of the drive assembly of the present
invention.
[0023] FIG. 5 is a side view of the drive assembly of the present
invention.
[0024] FIG. 6 is a side view of the drive assembly of the present
invention.
[0025] FIG. 7 is an exploded view of the bevel gear assembly of the
present invention.
[0026] FIG. 8 is an exploded view of the gear clamp assembly of the
present invention.
[0027] FIG. 9 is an exploded view of the crank assembly of the
present invention.
[0028] FIG. 10 is an exploded view of the prop cassette assembly of
the present invention.
[0029] FIG. 11 is a side view of the eccentric idler assembly of
the present invention.
[0030] FIG. 11a is a schematic view of the drive assembly of the
present invention.
[0031] FIG. 11b is a schematic view of the drive assembly of the
present invention.
[0032] FIG. 11c is a schematic view of the drive assembly of the
present invention.
[0033] It is noted that the drawings of the invention are not
necessarily to scale. The drawings are merely schematic
representations, not intended to portray specific parameters of the
invention. The drawings are intended to depict only typical
embodiments of the invention, and therefore should not be
considered as limiting the scope of the invention. The invention
will now be described with additional specificity and detail
through the accompanying drawings.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS
[0034] The present invention is directed to an improvement over
U.S. Pat. No. 6,210,242 which is hereby incorporated by
reference.
[0035] With reference to FIGS. 1, a pedal-powered watercraft or
kayak 10 according to the invention is illustrated. The watercraft
10 includes a hull 12, a pedal drive assembly 13, a deck 14, a keel
15, a stern 16 and a retractable rear rudder 17. The keel 15 is
closed within the hull 12 to move within the water without allowing
the water to pass through the watercraft from keel 15 to stem 16.
Unlike the watercraft described in U.S. Pat. No. 6,210,242, the
water is forced out of the way of the watercraft during travel and
leaves substantially no wake in the path of the kayak 10. The hull
further includes a central body portion 18 having a bottom surface
19 with a centrally formed concave recess 20 extending the length
of the central body portion 18. A retractable rear rudder 17 is
attached to the rear of the stern 16 and is used for guiding the
watercraft 10.
[0036] Turning to FIGS. 2-11, the drive assembly 13 includes a
drive housing 100 comprised of an injection-molded glass reinforced
urethane material and is vacuum molded by forming a first half
section 101 and a second half section 102. Positioned into the
drive housing 100 is an upper crankshaft assembly 103 complete with
crank arms 104, 105 (70,71) and pedals 106, 107 The crankshaft
assembly 103 operates a chain 110 which turns a bevel gear assembly
120. The bevel gear assembly 120 rotates a prop cassette assembly
140. The chain 110 is tensioned by an eccentric idler 111. The
bevel gear assembly 120 changes the direction of rotation 90
degrees as well as increasing the rotating speed three times. The
rotating speed is also increased between the crankshaft assembly
103 and the bevel gear assembly 120 three times, for a net
overdrive of approx. six times, creating the speed necessary for a
propeller drive. This overdrive ratio between the pedals 106, 107
vs. propeller shaft can be adjusted, by changing the crankshaft
sprocket size to approx. 5:1 to over 8:1.
[0037] The drive assembly 13 is completed by joining the first half
section 101 and second half section through means of a grooved glue
joint 108 entirely encircling first half section 101 and second
half section 102 and prop-shaft cassette 140. Glue is also inserted
in the chain guide groove 109 creating a center reinforcing rib
109a in the drive assembly 13 when tongue portion 112 of chain
guide 113 is joined as the first half section 101 and second half
section 102 are brought together. The glue joint 108 has standoff
points all around its perimeter, leaving a 0.030'' void 108b around
the perimeter. This 0.030 void 108b leaves room for adjustments in
size between the first half section 101 and the second half section
102.
[0038] With reference to FIG. 9, the upper crankshaft assembly 103
consists of a crankshaft 160 machined on each end to accept bicycle
style crank arms into which standard bicycle pedals 106, 107 are
fitted. The crankshaft 160 has a keyway 161 machined for a key 162
which locks a chain sprocket 163 to the crankshaft 103 The chain
sprocket 163 rest firmly against a spacer 164 held in place by a
lock ring 165 fitted into a groove 166 machined into the crankshaft
103. Metal bearing races are fitted into the inside of first half
section 101 and of second half section 102 and sealed with O-rings
168. Outer metal seal races 168 with lip seals 169 installed are
then threaded into female threads inside the bearing races 172.
This creates a metal race firmly clamped to the first half section
101 and the second half section 102 for the crankshaft bearings
173. There is an internal groove inside the bearing races 172 with
an o-ring 170 fitted in that groove. This completes sealing the
races 168, 172 to the first half section 101 and the second half
section 102. Bearings 173 mounted into the races 172 provide
support during rotation of the crankshaft assembly 103, while the
seals 169 seal oil in and water out. When the housing 100 is
joined, a wavespring 174 holds the bearings 173 firmly in their
races 168 and inhibits side to side thrust of the crankshaft
assembly 103.
[0039] The crankshaft assembly 103 moves the chain 110 which
rotates the bevel gear assembly 120. It does so by turning a bevel
gear 121 with a sprocket 122 attached. A hardened axle 123 is
inserted through the hole 124 in the bevel gear 121. The gear 121
and axle 123 rotate on bushings 125 fitted into bores 126, 127, the
first half section 101 and the second half section 102. The bevel
gear 121 is positively positioned by a shim washer 128 fitted
between the back side of the bevel gear 121 and the bushing
125.
[0040] The bevel gear assembly 120 then turns the prop-shaft
assembly 140 and changes the direction of rotation 90 degrees. It
does so by engaging the pinion gear 141 which is attached to
prop-shaft 142 by a roll pin 143 inserted through holes 144, 145 in
the prop-shaft 142 and pinion gear 141. The prop-shaft 142 rotates
on bearings 146 positioned on the prop-shaft by a spacer 147 which
rests firmly against the pinion gear 141. The bearings 146 are
spaced apart by an inner spacer 148 and an equal length outer
spacer 149. The bearings 146 are held tight against the pinion gear
141 and spacer 151 by a wavespring 152 sandwiched between 2 washers
152a and held firmly in place by a lock ring 153 fitting into a
groove 154 machined into the prop shaft 142. Prop-shaft/bearing
assembly 155 slides into prop-shaft cassette 140 with the assembly
resting against a wavespring 156 held into the prop-shaft cassette
140 by a lock ring 156b fitting into a groove machined into the
inside of the prop-shaft cassette 140. This entire assembly is held
in place in the prop shaft cassette 140 by the prop-nut 157. The
prop-nut 157 screws into female threads in the prop-shaft cassette
140. There is a lip 157a on the front of the prop-nut 157 that
rests on the bearing 146 outer-race. This forces the
bearing/prop-shaft assembly 155 inward against the wavespring 152e
hence the pinion gear 141 in against bevel gear 121 this is how
their gear lash is adjusted. The amount the prop-nut 157 is
threaded in is set by shims 158 between the edge 159a of the
prop-nut and the edge 159b on the prop-shaft cassette 140. The
prop-nut (29) is sealed to the cassette 140 by an o-ring 159c
fitted into a machined groove in the cassette 140. The prop-shaft
assembly 140 is double sealed by two lip seals 159d pressed into
the prop-nut 157 sealing oil in and water out. The wavesprings 152,
152e also act simultaneously as thrust springs for the prop-shaft
142.
[0041] The chain 110 is adjusted and tensioned by the eccentric
idler 111. This is done with a chain idler sprocket 201 and chain
idler sprocket bearing 202 mounted between two eccentric housings
203, 204. The eccentric housings 203, 204 are formed so that the
idler sprocket 201 and bearing 202 are mounted on a shaft 205
created when the eccentric housings 203, 204 are fitted together.
The center of this shaft 205 is eccentric with the center of the
outer edge of the eccentric housings 203, 204 which rotate in
openings 206 formed in the first half section 101 and the second
half section 102. This rotation causes the idler sprocket 201 and
bearing 202 to move in and out to tension the chain 110. The
rotation of the eccentric housings 203, 204 is locked in position
by placing a pin 206 between a groove 207 in the eccentric housings
203, 204 and the corresponding groove 208 in both the first half
section 101 and the second half section 102. The three grooves 208)
in the housings in the first half section 101 and a second half
section 102 are placed to allow incremental rotations of the
eccentric idler 111 of 2.5 degrees. The eccentric idler 111 is
sealed to the first half section 101 and the second half section
102 by two o-rings 209, 210 fitted into grooves 208 molded into the
eccentric housings 203, 204.
[0042] An schematic view of the operation of the eccentric idler is
displayed in FIGS. 11a-11c. As the kayak is peddled by the user,
eccentric idler 111 causes tension on the chain 110 as the sprocket
201 moves to the position shown in FIG. 11a inside the race bearing
202 and eccentric housings 203, 204. As illustrated in FIG. 11b,
the sprocket and bearing have moved to a slightly slackened
position resting on the opposite side of the eccentric housings
203, 204. As the sprocket and bearing move to the position shown in
11c tension is once again placed on the chain 110 and drive
assembly 13.
[0043] The drive assembly 13 is mounted to the hull 12 of the boat
10 by two pairs of drive collars 230-232 firmly clamped around the
housing bearing surfaces of the drive. The drive collars 230-232
are held together with bolts 234 and spacers 236. The lower drive
collars 230, 231 are attached to the hull firmly anchoring the
entire drive assembly 13 to the hull 12. An additional clamping
force is provided by o-rings 237, 238 fitted into a groove in the
drive collars 230-232. These large o-rings 237, 238 also act as a
friction ring between the drive assembly 13 and the drive collars
230-232. Each friction ring 237, 238 holds the drive assembly 13 in
the retracted (up) position.
[0044] With the drive collars 230-232 anchored to the hull 12, the
drive assembly 13 can be rotated about the bearing surfaces 240 on
the drive assembly and the collars 230-232 by the use of a handle
250 with a non-slip grip 251. The drive handle 250 is held in a
drive bracket 252 by a removable clevis pin 253 and lock ring 254.
The drive bracket 252 is mounted to the drive assembly 13 by three
machine screws 255 and nuts 256 passing through two holes 257 in
the first half section 101 and the second half section 102 and one
hole 258 through the eccentric idler 111. This allows the drive
assembly 13 to be retracted into a trunk 260 (formed in the hull)
for shallow water, beaching, or transporting. The entire drive
assembly 13 can also be removed from the hull by removing the four
bolts and spacers 234, 235 and the upper drive collars 233(3). The
drive assembly 13 will now lift out of the lower drive collars 230,
231 cradling it.
[0045] A pedal powered boat having a drive assembly including an
eccentric idler provides a tension and adjustment during operation
of the pedal drive. A crankshaft assembly and a bevel gear assembly
are uniquely combine to produce a smooth pedaling operation for the
user. The bevel gear assembly is operable to change the direction
of rotation 90 degrees and increasing the speed three times for a
net overdrive of six times for creating the speed necessary for a
propeller drive.
[0046] While the invention has been taught with specific reference
to the above-described embodiments, those skilled in the art will
recognize that changes can be made in form and detail without
departing from the spirit and the scope of the invention. For
example, in each of the above embodiments one or more of the foot
pedals can be replaced with hand pedals for accommodating
handicapped persons or for exercising the upper body.
[0047] Thus, the described embodiments are to be considered in all
respects only as illustrative and not restrictive. The scope of the
invention is, therefore, indicated by the appended claims rather
than by the foregoing description. All changes that come within the
meaning and range of equivalency of the claims are to be embraced
within their scope.
* * * * *