Patent Publication Number: US-6039137-A

Title: Multi-terrain electric motor driven cycle

Description:
TECHNICAL FIELD 
     The invention pertains to the general field of power driven cycles and more particularly to a multi-terrain, monoplaner frame cycle that is powered by an electric motor. 
     BACKGROUND ART 
     In recent years many alternative means of providing power for vehicles have been developed. One of the most popular and promising power means is electricity. Several auto makers have begun to offer electricity-powered vehicles, such as Ford and General Motors with their EV-1 electric cars and Toyota with their hybrid gas and electric Privus vehicle. 
     One of the reasons that it is difficult to design electric vehicles, such as automobiles, is the inability to provide long-lasting, sufficient power without having to utilize an extremely large number of heavy batteries. It was the obvious weight requirements of a passenger automobile that led designers to consider the possibility of electrically-powered two-wheeled cycles, such as motorcycles and bicycles which have a substantially lower weight and lower power requirements. 
     One of the major drawbacks to designing and building electrically-powered two-wheeled cycles was that manufacturers were currently selling a large quantity of gasoline-powered cycles and cycles using electrically assisted hybrid power systems. There was not a great deal of incentive to invest substantial amounts of money into research, development and subsequent building of a product that was already selling well as currently designed. However, even with a lack of incentives, the current multi-terrain electric motor driven cycle disclosed herein was designed and manufactured. The inventive cycle offers an alterative design to currently available gasoline or hybrid powered cycles. 
     A search of the prior art did not disclose any patents that read directly on the claims of the instant invention, however the following U.S. patents are considered related: 
     
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U.S. PAT. NO.                                                             
             INVENTOR      ISSUED                                         
______________________________________                                    
    5,474,148                                                             
             Takata        12 December 1995                               
5,226,501    Takata        13 July 1993                                   
3,921,745     McCulloch, et al                                            
                              25 November 1975                            
______________________________________                                    
 
    
     The U.S. Pat. No. 5,474,148 discloses a bicycle having an electric motor assist. The assist ratio provided by the electric motor is varied in response to a variety of bicycle conditions, such as speed, to reduce the consumption of electrical energy and to avoid over speed conditions. Various control ratio options are available and the operator may select the assist ratio. 
     The U.S. Pat. No. 5,226,501 discloses an electric power bicycle wherein an electrical motor is employed for assisting in the pedaling of the bicycle. An arrangement is included for changing the state of the electrical power when the bicycle is pushed. The circuit for the electric motor is opened when the bicycle is pushed rearwardly so as to avoid undue resistance to the pushing. In other embodiments, the electric motor is energized upon pushing so as to assist in pushing the bicycle. 
     The U.S. Pat. No. 3,921,745 discloses an electric bicycle employing a chain, V-belt or friction pulley drives and a motor controller circuit variable in both frequency and duty cycle. Regenerative braking and the conversion of the motor to a transformer for charging the bicycle battery is disclosed. The pressure of the armature brushes of the motor is variable under light load conditions to increase motor efficiency. 
     For background purposes and as indicative of the art to which the invention is related reference may be made to the remaining cited patents. 
     
         ______________________________________                                    
U.S. PAT. NO. INVENTOR    ISSUED                                          
______________________________________                                    
5,491,390     McGreen     13 February 1996                                
5,375,676                 Takata et al                                    
                                    27 December 1994                      
5,370,200            Takata                                               
                                           6 December 1994                
4,871,042                 Hsu et al                                       
                                     3 October 1989                       
3,961,678             Hirano et al                                        
                                     8 June  1976                         
______________________________________                                    
 
    
     DISCLOSURE OF THE INVENTION 
     The multi-terrain electric motor driven cycle is built around a monoplaner frame and is primarily designed for use as an &#34;off road&#34; cycle. The term monoplaner is used herein to differentiate from a conventional motorcycle frame which typically uses several laterally placed tubes to establish width. In contrast, bicycles are constructed on a single frame having a vertical plane such as the monoplaner frame of the present invention. The use of a monoplaner frame design for electric motor driven cycles is now practical because of the components used on &#34;mountain bikes&#34; such as spring loaded and dampened suspension system and a braking system that uses hydraulic disc brakes. 
     The inventive cycle also employs a unique design for packaging a pair of battery packs. These battery packs are enclosed within a right and left battery housing which provide nearly equal front and rear tire loading, and account for at least 50 percent of the total cycle weight. The battery packs are also designed to be used individually or in combination to power the cycle&#39;s electric motor. 
     The cycle design also features a front and rear damping assembly, a hydraulic braking system that operates both the front and rear wheels by means of levers attached to a handlebar, a steering stop which prevents acute steering angles, a centerstand, a pair of footpegs and an electrical power control system. 
     The centerstand has two downward extending legs and is centrally located with respect to the cycle&#39;s longitudinal center of gravity. This allows the cycle to remain balanced when either the front or rear wheel is removed for servicing. Also, the legs of the centerstand have sufficient lateral width that if either of the side mounted battery housings are removed, the cycle&#39;s lateral center of gravity remains between the two legs of the centerstand to prevent the cycle from falling sideways. 
     The cycle drive assembly employs two stages of gear reduction. The first stage produces a ration of 3 or 4 to 1 and consists of the electric motor, a toothed belt, a first sprocket attached to the motor shaft, and a second sprocket. The second stage also produces a ration of 3 or 4 to 1 and consists of a chain ring which is attached to the rear wheel and is driven by a chain drive connected to a third sprocket which is coaxially attached to and driven by the second sprocket. The first stage is selected for quietness and efficiency of operation at a higher motor speed of approximately 5000 RPM. The second stage is selected for higher torque requirements. 
     A unique design of the cycle is that the monoplaner frame utilizes a lower tube, also referred to in cycle jargon as a &#34;bottom bracket&#34;. This lower tube integrates the footpegs, the centerstand, the first and second sprockets, and the electric motor. The lower tube, due to its position and strength, provides an ideal node for comfortable, safe riding. The vehicle weights 150 pounds and has a maximum capacity of 225 pounds which provides for a cycle capacity that is 1.5 times greater than its weight. 
     The electrical power control circuit consists of a battery power source which contains two battery packs, a built-in battery charger, a power control switch that controls the operation of a solenoid, a power/speed control circuit that is operated by an electronic throttle circuit and which produces a signal that controls the speed of the electric motor. 
     In view of the above disclosure, it is the primary object of the invention to produce a multi-terrain electric motor driven cycle that utilizes a monoplaner frame design which includes an electric motor that is powered by a pair of balanced right and left battery housings which contain the battery packs. 
     In addition to the primary object it is also an object of the invention to produce a cycle that: 
     utilizes a design which incorporates in the monoplaner frame a front and rear wheel hydraulic braking system, a front and rear damping assembly, an optimized cycle drive system, an electrical power control system, and other elements that make the cycle safer and provide greater terrain capabilities than can be negotiated by current cycle models, 
     includes a built-in battery charger, 
     is relatively reliable and maintenance free, with the exception that the battery packs must be periodically charged by the built-in battery charger which is activated when connected to 120 volts a-c, 
     when the batteries are fully charged, the cycle can be driven for approximately 35 miles, and 
     is cost effective from both manufacturing and consumer points of view. 
     These and other objects and advantages of the present invention will become apparent from the subsequent detailed description of the preferred embodiment and the appended claims taken in conjunction with the accompanying drawings. 
    
    
     BRIEF DESCRIPTION OF THE DRAWINGS 
     FIG. 1 is a right side elevational view of the multi-terrain electric motor driven cycle. 
     FIG. 2 is a top plan view of the cycle. 
     FIG. 3 is a right side elevational view of the cycle with the right battery housing, left battery housing and a portion of the electronic power control system removed for clarity. 
     FIG. 4 is a partial right side elevational view showing the details of the rear shock absorbing assembly. 
     FIG. 5 is a partial right side elevational view showing the details of the cycle drive system. 
     FIG. 6. is a partial right side elevational view showing the details of the centerstand and the location of a portion of the electronic power control system. 
     FIG. 7 is a combination block/schematic diagram of the electronic power control system. 
    
    
     BEST MODE FOR CARRYING OUT THE INVENTION 
     The best mode for carrying out the invention is presented in terms of a preferred embodiment for a multi-terrain electric motor driven cycle 10. The preferred embodiment, as shown in FIGS. 1-7, is comprised of the following major elements, a monoplaner frame 12 consisting of a head tube 14, a seat tube 20, an upper crossbar assembly 38, a front tube 60, a lower tube 78, a front damping assembly 94, a front wheel 122, a rear fork assembly 126, a rear wheel 160, a rear damping assembly 166, a rear shock absorbing assembly 180, an electric motor 200, a battery tray 214, a protective cover 220, a right bettery housing 224, a left battery housing 226, a cycle drive assembly 240, a braking system 260, a handlebar 270, a right foot peg 282, a left foot peg 284, a centerstand 294, and an electrical power control circuit 300. 
     The multi-terrain electric motor driven cycle 10 is based on a fully suspended and dampened monoplaner structure frame design. The term monoplaner is used to differentiate from a conventional motorcycle frame which uses more laterally placed frame tubes to establish width. The use of a monoplaner frame has only recently become practical for use on electric cycles due to the recent rise in mountain bike technology which includes the use of spring loaded and dampened suspensions and hydraulic disc brakes. 
     The monoplaner frame 12, as shown in FIGS. 1, 2 and particular in FIG. 3, is comprised of five structural members: a head tube 14, a seat tube 20, an upper crossbar assembly 38, a front tube 60 and a lower tube 78. 
     The head tube 14 includes a top race 16 and a bottom cup 18. The seat tube 20 has an upper end 22 to which is attached a slot 23, a lower end 24, an outer surface 26, an inner surface 28 and sides 30. From the inner surface 28 is attached a first bifurcated bracket 32 and from each of the sides 30 and near the upper end 22 of the seat tube 14 extends outward a battery housing attachment structure 34. Also from each side 30 and below the first bifurcated bracket 32 extends outward a rear battery tray support rod 36. 
     The upper crossbar assembly 38, as best shown in FIG. 3, is comprised of a first crossbar 40 and a second crossbar 54. The first crossbar 40 has first end 42, a second end 44, an upper surface 46 and a lower surface 48. The second end 44 is attached near the upper end 22 of the seat tube 20, and to the lower surface 48 is attached a second bifurcated bracket 50. The second crossbar 54 has a first end 56 attached to the head tube 14 and a second end 58 attached substantially at the center of the upper surface 46 of the first crossbar 40. 
     The front tube 60 includes an upper end 62, a lower end 64, sides 66, an outer surface 68, and an inner surface 70. The upper end 62, as shown best in FIG. 3, is attached to the head tube 14, and to the inner surface 70 is attached the first end 42 of the first crossbar 40. From each of the sides 66 and near the attachment of the first crossbar 40 extends laterally a battery housing retaining/pivot rod 72. Near the lower end 64 and from each of the sides 66 also extends laterally a front battery tray support rod 74. 
     The lower tube 78 has a front end 80 and a rear end 82. The rear end 82 is attached near the lower end 24 of the seat tube 20. At the intersection of the lower tube 78 and the seat tube 20 is attached a third bifurcated bracket 84. To the rear end 82 is attached an upper front surface 88 of a motor mount sleeve 86, which also has a rear surface 90 that is attached to the front end 80 of the lower tube 78. The sleeve 86, which is dimensioned to enclose the electric motor 200 includes a means for tightening the sleeve around the motor 200. 
     The front damping assembly 94, as shown in FIGS. 1 and 3, includes a bifurcated member 96, a right damping tube 108 and a left damping tube 110. From the upper surface of the bifurcated member 96 is a centered, upward-extending steering tube 98 that is rotatably inserted into the bottom cup 18 of the head tube 14. The member 96 also has a right end 100 and a left end 102, wherein each of these ends have a bore 106 therethrough. Both the right and left damping tubes 108,110 enclose a spring 112, and have an upper end 114 and a lower end 116. The upper ends 114 are inserted into and attached to the respective bores 106 on the right and left ends 100,102 of the bifurcated member 96. The lower ends 116 of the right and left damping tubes 108,110 form a front fork 118. Into the front fork 118 is inserted on axle 124 of the front wheel 122 as shown in FIGS. 1, 2 and 3. For clarity, the left end 102 of the bifurcated member 96 and the left damping tube 110 are not shown in the figures. 
     The rear fork assembly 126 is comprised of a right bracket 128, a left bracket 138, a right linkage actuator arm 140, a left linkage actuator arm 146, a lower right fork member 148 and a lower left fork member 154. Again for clarity, the left components which are identical to the right components, are not shown in the figures. 
     The right bracket 128 includes a vertical section 130 having an outward rear wheel attachment slot 132, and a horizontal section having a pair of brake mounting bores 136. The right linkage actuator arm 140 has a front end 142 and a rear end 144. The rear end 144 is attached to the vertical section 130 of the right bracket 128. Likewise, the left linkage actuator arm 146 has a front end 142, and a rear end 144 that is attached to the vertical section 130 of the left bracket 138. 
     The lower right fork member 148 includes a front end 150 and a rear end 152. The front end 150 is attached to the third bifurcated bracket 84, which is located at the intersection of the seat tube 20 and the lower tube 78. The rear end 152 is attached to the vertical section 130 of the right bracket 128. Likewise, the lower left fork member 154 has a front end 150 and a rear end 152 that is also attached to the third bifurcated bracket 84. The rear end 152 is attached to the vertical section 130 of the left bracket 138. Into the wheel attachment slots 132 on the right bracket 128 and the left bracket 138 is inserted the axle 162 of a rear wheel 160. 
     The rear damping assembly 166, as best shown in FIG. 4, is comprised of a pair of rear linkage rocker arms 168 and the rear shock absorbing assembly 180. The rear linkage rocker arms 168 each have an upper bore 170, a center bore 172 and a lower bore 174. The lower bores 174 are rotatably attached by means of a bolt 176 to the first bifurcated bracket 32. The upper bores 170 are rotatably attached by means of a bolt 176, to each of the respective front ends 142 of the right linkage actuator arm 140. The left linkage actuator arm 146 is not shown in FIG. 4 for clarity. 
     The rear shock absorbing assembly 180 is comprised of a damping cylinder 182, a damper rod 188 and a spring 196. The damping cylinder 182 has an upper end 184 and a lower end 186. From the upper end 184 extends the damper rod 188 which has on its upper end 190 a rod attachment structure 192 that is attached to the second bifurcated bracket 50 as shown in FIG. 4. From the lower end 186 of the cylinder 182 is a cylinder attachment structure 194 that is attached by means of a bolt 176 to the center bore 172 located on the pair of rear linkage rocker arms 168. Around the damping cylinder 182 is located the spring 196 that includes a means for adjusting its compressive force. 
     The protective cover 202 and the battery tray 214 are shown in FIGS. 1 and 3. The protective cover 202 has an upper surface 204, a lower surface 206, a front end 208 having a central front slot 209, a rear end 210 having a central rear slot 211 and a centered opening 212. To secure the cover 202, the front slot 209 is inserted into the front tube 60, the rear slot 211 is inserted into the seat tube 20 and the centered opening 212 is placed over the second bifurcated bracket 50. When the cover is attached, the upper surface 204 of the cover 202 presses against the lower surface 48 of the first crossbar 40. 
     The battery tray 214 has an upper surface 216 and a lower surface 218. The lower surface 218 rests upon and is attached to the front and the rear battery tray support rods 74,36. 
     The right battery housing 224 and the left battery housing 226 each have an upper surface 228, a lower surface 230 and are sized to enclose the respective first and second battery packs 304,306 as described infra. The housings, which are shown in FIGS. 1 and 2 attached to the cycle 10, are designed to be easily installed and removed. To accomplish the installation and removal each of the housings has a front lateral bore 232 and a rear lateral bore 234. The front bore 232 is dimensioned to slide into the housing pivot rod 72 as shown best in FIG. 3. Into the rear bore 234, which is in alignment with the battery housing attachment structure 34, as also shown best in FIG. 3, is inserted a bolt 236 that secures the battery housings 224,226. 
     The cycle drive assembly 240, as shown best in FIG. 5, is comprised of a first sprocket 242, a second sprocket 244, a toothed belt 248, a third sprocket 250, a chain ring 252 and a chain drive 256. The first sprocket 242 is attached to the shaft of the electric motor 200 and the second sprocket 244 is attached to a drive shaft 246 which extends laterally from the third bifurcated bracket 84. The second sprocket 244 is driven by the toothed belt 248 which is connected to the first sprocket 242. The third sprocket 250 which is coaxially attached to and is driven by the second sprocket 244, is connected to the chain ring 252 via the chain drive 253. The chain ring 252 is concentrically attached to the side of the rear wheel 160. 
     The above-described cycle drive assembly 240 allows the cycle 10 to utilize two stages of gear reduction: the first stage produces a ration of 3 or 4:1 and is comprised of the electric motor 200, the toothed belt 248, the first sprocket 242 and the second sprocket 244. The second stage which also produces a ratio of 3 or 4:1 consists of the chain ring 252 which is driven by the chain drive 256 attached to the third sprocket 250. 
     The braking system 254, as shown in FIGS. 1 and 2, is comprised of a front brake assembly 262 and a rear brake assembly 274. The front brake assembly 256 is comprised of a right brake disc 258 attached to the right side of the front wheel 122 and a left brake disc 260 attached to the left side of the front wheel 122. The two discs function in combination with a closed-loop hydraulic system 262 that is operated by a left brake lever 264. The lever 264 is located on the left side of the handlebar 270 which includes a vertical shaft 272, as shown in FIG. 3, that is inserted into the top race 16 of the head tube 14. 
     The rear brake assembly 274 is comprised of a left brake disc 276 that is attached to the left side of the rear wheel 160. The left brake disc 276 also functions in combination with a closed-loop hydraulic system 278 that is operated by a right brake lever 280 located on the right side of the handlebar 270. 
     To complete the mechanical structure of the cycle 10, the right foot peg 282, the left foot peg 284, the centerstand 294 and a steering stop 299 are utilized. 
     The right and left foot pegs 282,284, as shown in FIG. 2, are each comprised of a horizontal section 286 having an inward end 288 and an outward vertically slotted end 290. The inward end 288 is attached to the respective right and left sides of the third bifurcated bracket 84. From the slotted end 290 extends outward an articulated foot rest 292 that can be extended for use and retracted when the cycle 10 is parked. 
     The centerstand 294 consists of an upper section 296 from where extends downward and outward a pair of laterally spaced legs 298. The upper section 296 is swivelly attached to the third bifurcated bracket 84, which allows the centerstand to be place din a retracted position (not shown) or in a downward, functional position as shown in FIG. 6. The centerstand 294 allows the cycle 10 to remain balanced when either the front wheel 122 or the rear wheel 160 is removed for servicing. Also the legs 298, have a sufficient lateral separation so that if either of said battery housings 224,226 is removed, the lateral center of gravity remains between the two legs 298 which prevents the cycle 10 from falling sideways. 
     The steering stop 299, which is shown in FIG. 1, is located between the bottom cup 18 of the head tube 14 and the front damping assembly 94. The steering stop is designed to prevent a cycle user from the danger of acute steering angles. 
     The electrical power control circuit 300, which controls the power applied to the electric motor 200 is shown in FIG. 7 and is comprised of a battery power source 302. The power source 302 consists of first battery pack 304 and a second battery pack 306, a battery charger 312, a power control switch 320, a solenoid 326, a power/speed control circuit 340, an electrical throttle circuit 346 and an optional battery potential indicator 352. As shown in FIG. 1, the battery power source 302 is distributed among the right and left battery housings 224,226 which are located on each side of the monoplaner frame 12. The battery charger 312, the solenoid 326, the power/speed control circuit 340 and the electronic throttle circuit 346 are located within the area bordered by the seat tube 20, the first crossbar 40, the front tube 60 and the lower tube 78 as shown in FIG. 6. The remaining items, namely the power control switch 320, the mechanical throttle 348 and the battery potential indicator 352 are located in the vicinity of the head tube 14 and handlebar 270 as shown in FIG. 1. 
     The first battery pack 304, which is located within the right battery housing 224, has a positive and negative output, and a positive and negative input which are connected to a first input connector 308. Likewise, the second battery pack 306, which is located within the left battery housing 226, has positive and negative outputs which are connected in parallel with the positive and negative outputs of the first battery pack 304. The second battery pack 306 also has a positive negative inputs which are connected to a second input connector 310. In a preferred embodiment, the first and second battery packs 304,306 are each comprised of a first rechargeable battery set and a second rechargeable battery set. Each battery set consists of three 12-volt batteries connected in series and the first and second battery sets are connected in parallel. This configuration provides a total voltage output of 36 volts per battery pack with a capacity of 1150 watt hours. 
     The combination of the first and second battery packs 304,306 and the right and left battery housings 224,226 account for at least fifty percent of the total cycle weight. The housings are also located to provide a substantially equal front wheel-to-rear wheel loading. Additionally, a means is provided for allowing one of the battery packs to supply power to the cycle 10 while the other battery pack remains in a standby mode. This means is well known in the art and can consist of connectors or switches placed at the output/input of the power packs. 
     The battery charger 312 has a power input plug 314 that when connected to a utility 120 volts a-c power source the charger 312 becomes operational. The battery charger 312 includes a first output connector 316 and a second output connector 318 that is connected in parallel with the first output connector 316. The first and second output connectors 316,318 can be selectively attached to the first input connector 308 and/or the second input connector 310 as shown in FIG. 7. 
     The battery charger 312 is preferably designed to have a watt density of at least 15 watts per cubic inch and a power output of at least equal to the ampere hour capacity of the first and second battery packs 304,306. These design parameters insure a maximum one-hour bulk battery recharge capability. Additionally, the battery charger can be designed with a circuit means for providing an automatic cutoff. This cutoff which is well known in the art can be based on time or voltage or a combination of time and voltage. 
     The power control switch 320 has first contact 322 and a second contact 324. The first contact 322 is connected to the negative output of the battery power source 302. 
     The solenoid 326 has a first contact 328, a second contact 330 and a control coil 332 which has a first terminal 334 and a second terminal 336. The first contact 328 and the first terminal 334 of the coil 332 are connected to the positive output of the battery power source 302. The second terminal 336 is connected to the second contact 324 of the power control switch 320. 
     The power/speed control circuit 340 includes a circuit means for receiving a power input, a speed control signal 342 and producing a motor control signal 344. The power input consists of a positive input applied from the second contact 330 of the solenoid 326 and a negative input applied from the negative output of the battery power source 302. The power/speed control circuit 340 utilizes a combination of pulse-width modulation and variable duty cycle switching to control the current and voltage levels of the motor control signal 344, which is applied to and controls the speed of the electric motor 200. 
     The electronic throttle circuit 346 includes a mechanical throttle 348 and a means for producing the speed control signal 342, which is applied to the power/speed control circuit 340. This signal is variable and is dependent upon the rotational displacement of the throttle 348 applied by a user of the cycle 10. The throttle 348 incorporates a potentiometer 350 which varies a control voltage that is proportional to the rotational displacement of the throttle. This control voltage provides a regulated current to the electric motor 200, via the electronic throttle circuit 346, which causes acceleration. The acceleration continues until a throttle set point is reached or the throttle is retarded. The combination of the power/speed control circuit 340 and the electronic throttle circuit 346 can also be designed to include the operation of a speed governer (not shown). 
     The operation of the electrical power control system 300 commences when the power control switch 320 is closed by the cycle user. The closing of the switch 320 energizes the solenoid 326 which then activates the power/speed control circuit 340. The motor control signal 344 produced by the circuit 340 is applied to the electrical motor 200. The rotational speed of the motor 200 is controlled by the combination of the power/speed control circuit 340, the electronic throttle circuit 346 and the mechanical throttle 348. 
     While the invention has been described in complete detail and pictorially shown in the accompanying drawings it is not to be limited to such details, since many changes and modifications may be made in the invention without departing from the spirit and scope thereof. Hence, it is described to cover any and all modifications and forms which may come within the language and scope of the appended claims.