Transmission

Abstract: A transmission applying totally meshing gear sets to transmit power, wherein a sleeve 21,22,23,24,25 is used to loosen or twist a spring 211,221,231,241,251 inside the gear set so as to select the required gear set to transmit power, and several sequential sets of driving transmission ratios are provided. When shifting gear, the accelerator does not need to be released and can be continuously held down. A microprocessor will, according to data sent from detecting devices detecting the rotational speed of the input shaft, properly control shifting operations so that automatic shifting operations can be quickly, accurately and sensitively performed, permitting the engine to provide output power at maximum efficiency.

Description: The present invention relates to a transmission, and more particularly to a vehicle-used totally meshing automatic transmission. All experienced vehicle drivers know that to drive car with automatic transmission is much easier than to drive a car with a manual transmission. Because when driving a manual-transmission car, each gear-change procedure requires six steps, i.e. releasing the accelerator, depressing the clutch pedal, moving the gear lever from its original position into new position, releasing the clutch pedal, and then depressing the accelerator. On a road with complicated traffic, doing such steps repeatedly will naturally make the driver bothered and impatient, and danger is apt to be caused. Moreover, when changing gear, the accelerator is released to thus cause power loss, and when gear changing occurs during going up an inclined plane, if the gear lever is not properly moved to its new position, the engine might stall. Furthermore, because the gear-change procedure is too complicated, the driver often is not willing to change gear when it is required. Therefore, the engine often operates at an improper rotating speed to waste energy and cause engine damage. On the other hand, conventional automatic transmissions have quite complex structures including planet gear sets, clutch, brake, controller, etc. and the manufacturing cost is relatively high, and all the elements require regular adjustment to increase service cost. Moreover, the transmission efficiency of automatic transmissions is low and the power loss thereof is 18% greater than manual transmissions. Thus, the automatic transmissions cannot be popularly applied. Therefore, step less transmissions have been developed to improve the above two transmissions. Two advantages of step less transmissions are first the structure is simple and it can be easily controlled, and second the engine can always operate at economic speed to output power with highest efficiency. However, step less transmissions have two shortcomings, one of which is the speed-changing control is slow and often it will change shift position by means of abruptly depressing the accelerator, and the other of which is the driving chain is closely clamped the wheel disks and thus the frictional loss is very large. Step less transmissions are thus not widely used due to the above two drawbacks. From US-A 2 086 563 is known a transmission with a housing, an input shaft and an output shaft, said transmission providing a plurality of gear ratios and further comprising a counter shaft; a driving gear assembly having several driving gears the number of which equals to that of the gear ratios to be selected, said driving gears having different diameters and being fitted on said counter shaft in sequence from the small diameter one to the large diameter one; a forward drive gear ratio shift control assembly; a reverse gear assembly having a reverse gear fitted on the rear end of said counter shaft to rotate therewith, said reverse gear engaging an idle gear which meshes with a gear arranged on said output shaft; a driven gear assembly having several driven gears the number of which equals the sum of the reverse and driving gears, said driven gears having different diameters and being fitted on said output shaft in sequence from a small diameter one to a large diameter one and meshing with said driving and idler gears, each driven gear having a coupling means which connects said driven gear with said output shaft whereby when said driving gears rotate, the driven gears meshing therewith are driven to rotate and a selected gear coupled to the output shaft rotationally drives the output shaft; and a forward/reverse/neutral drive mode shift control assembly being fitted on said output shaft and including a control means to control said coupling means to select either a forward or reverse gear ratio or the neutral shift. Therefore, a new transmission with high transmission efficiency is required to eliminate the aforesaid problems. It is a primary object of this invention to provide a transmission using a microprocessor which can, according to the speed of rotation of the engine, command a stepping motor to drive a shifting disk to automatically shift into a proper position. The control thereof is sensive and the action is actual so that the engine can be kept in most economic operating state with highest efficiency. It is a further object of this invention to provide a totally-meshing automatic transmission having the advantages of simplicity and high driving efficiency of manual transmissions without the disadvantages of the complex operating procedure thereof and having better control effects than known automatic transmissions. It is a still further object of this invention to provide a transmission wherein, when changing gear, the vehicle can be continuously accelerated without interrupting the power transmission and more gears can be added without increasing the complexity of structure and operation and by means of the microprocessor, the vehicle can be actually accelerated with strong and steady effect. According to the present invention there is provided a transmission comprising: a housing, an input shaft and an output shaft; the input shaft having a front half portion and a rear half portion; a driving gear assembly having several driving gear sleeves the number of which is equal to the number of gear ratios of the transmission, the driving gear sleeves having respective different diameters and being fitted on the front half portion of the input shaft in sequence from the smallest diameter one to the largest diameter one, each driving gear sleeve not being permanently rotatably driven by the input shaft; a forward gear control assembly having several slide sleeves with different diameters, the number of which is equal to that of the gear ratios, the slide sleeves being fitted on the rear half portion of the input shaft in sequence from the smallest diameter one to the largest diameter one, a first control means being used to control the engagement and separation of the slide sleeves and corresponding driving gear sleeves to select the gear ratio, each slide sleeve being rotatably driven by the input shaft and being capable of engaging its corresponding driving gear sleeve to cause rotation thereof; a reverse gear assembly having a reversing gear fitted on the rear end of the input shaft, the reversing gear engaging an idler gear; a driven shaft having a front portion, a middle portion and a rear portion; a driven gear assembly having several driven gear sleeves and a driven gear the combined number of which is equal to the number of driving gear sleeves, the driven gear sleeves having respective different diameters and being fitted on the front portion of the driven shaft in sequence from the smallest diameter one to the largest diameter one and meshing with respective driving gear sleeves, each driven gear sleeve having a third coupling means which connects the driven gear sleeves with one another and connects the driven gear sleeves with the driven shaft whereby, when each driving gear sleeve rotates, the driven gear sleeve meshing therewith is driven to rotate and rotationally drives in inward sequence each driven gear sleeve and the driven shaft; a forward/reverse gear assembly having two sleeves with different diameters, the sleeves being fitted on the rear portion of the driven shaft in sequence from the smaller diameter one to the larger diameter one, one of the sleeves being a forward sleeve, the other of the drive sleeves being a reverse sleeve having a gear which meshes with the idler gear, each sleeve having a fourth coupling means which connects the driven shaft with each sleeve whereby the driven shaft or idler gear can rotationally drive each sleeve; a forward/reverse/neutral control assembly having two slide sleeves with different diameters, the slide sleeves being fitted on the middle portion of the driven shaft with the smaller diameter one within the larger diameter one, a second control means being used to control the separation and engagement of the slide sleeves and the forward/reverse sleeves to select forward or reverse or neutral gear, each slide sleeve rotationally driving a corresponding sleeve; and the output shaft being connected to the forward/reverse gear assembly. Embodiments of the invention will now be described with reference to the following detailed description and drawings, in which: Fig.1 is a sectional view of a transmission in a neutral shift state; Fig.2 is a sectional view of an input shaft of the transmission in a non-fitted state; Fig.3 is a view similar to Fig.2, in which the input shaft is in a fitted state; Fig.4 is a sectional view of a gear-shifting disk in its neutral state; Fig.5 is a sectional view similar to Fig.4, in which the shifting gear disk is in a first ratio state; Fig.6 is a sectional view of the transmission in its first ratio state; Fig.7 is a sectional view of the gear-shifting disk in its third ratio state; Fig.8 is a sectional view of the transmission in its third ratio state; Fig.9 is a sectional view of the gear-shifting disk in its fifth ratio state; Fig.10 is a sectional view of the transmission in its fifth ratio state; Fig.11-1 is a sectional view of forward/reverse/neutral gear controller in which the shifting disk thereof is in its neutral state; Fig.11-2 is a sectional view corresponding to Fig.11-1, in which the shifting disk is in its reverse gear state; Fig.11-3 is a sectional view corresponding to Fig.11-1, in which the shifting disk is in its forward gear state; Fig.12 is a sectional view of the transmission in its reverse gear state; Fig.13 is a sectional view of a second input shaft in a non-fitted state; Fig.14 is a sectional view corresponding to Fig.13, in which the input shaft is in its fitted state; Fig.15 is a sectional view of a third input shaft in its non-fitted state; Fig.16 is a sectional view corresponding to Fig.15, in which the input shaft is in its fitted state; Fig.17 is a perspective and partially sectional view of a fourth input shaft; Fig.18 is a sectional view of a fourth input shaft in its non-fitted state; and Fig.19 is a sectional view corresponding to Fig.18 in which the input shaft is in its fitted state. Please first refer to Fig.1. The transmission of the embodiment of the present invention includes an input shaft 1, a driving gear assembly 2, a forward gear control assembly 3, a reverse gear set 4, a driven shaft 5, a driven gear assembly 6, a forward/reverse/neutral shift control assembly 7, a forward/reverse gear assembly 8, an output shaft 9 and a housing 10. The input shaft 1 extends into the housing 10 and serves as a driving shaft. The driving gear assembly 2 includes five driving gear sleeves 21,22,23,24,25 with increasing diameters. The number of the driving gear sleeves equals to that of the shifts. The five driving gear sleeves are telescoped on the input end portion of the input shaft 1 in such a manner that the input shaft 1 is loosely sleeved by a driving first-ratio spring 211 which is sleeved by the driving first-ratio gear sleeve 21 which is further sleeved by a driving second-ratio spring 221 which is sleeved by the driving second-ratio gear sleeve 22 which is sleeved by a driving third-ratio spring 231 which is further sleeved by the driving third-ratio gear sleeve 23 which is sleeved by a driving fourth-ratio spring 241 which is sleeved by the driving fourth-ratio gear sleeve 24 which is further sleeved by a driving fifth-ratio spring 251 which is finally sleeved by the driving fifth-ratio gear sleeve 25. Each driving shift spring is not directly closely sleeved on its lower driving shift gear sleeve and a clearance exists therebetween. The driving shift gear sleeves are respectively associated with bearings 212 ,222,232,242,252 and a bearing 26 is disposed externally to connect the whole driving gear assembly 2 with the housing 10. The forward gear control assembly 3 is fitted on the other end of the input shaft 1 by a selectively rotatable screw rod 31 meshing with a shift-gear disk 32 which is fitted on other end of the input shaft. Inside the shiftgear disk is disposed a forward gear engaging disk 33 and a driving first-ratio slide sleeve 34 is disposed on the input shaft which is sleeved by a driving first-ratio slide sleeve torque spring 341. The thickness of the driving first-ratio slide sleeve corresponds to that of the driving first-ratio spring and the thickness of the driving first-ratio slide sleeve torque spring 341 is fitted a driving second-ratio slide sleeve 35 which is sleeved by a driving second-ratio slide sleeve torque spring 351 which is sleeved by a driving third-ratio slide sleeve 36 which is sleeved by a driving third-ratio slide sleeve torque spring 361 which is further sleeved by a driving fourth-ratio slide sleeve 37 which is sleeved by a driving fourth-ratio slide sleeve torque spring 371 which is finally sleeved by a driving fifth-ratio slide sleeve 38 which is sleeved by a driving fifth-ratio slide sleeve torque spring 38. Each driving ratio slide sleeve torque spring is disposed between a flange of each slide sleeve and each gear sleeve. The thickness of each driving shift slide sleeve corresponds to that of each driving shift spring and the thickness of each driving shift slide sleeve torque spring corresponds to that of each driving shift gear sleeve to form several layers. Near the forward gear engaging disk 33, each driving shift slide sleeve is associated with a bearing 342, 352, 362, 372, 382. Therefore, the driving gear assembly 2 and forward gear control assembly 3 are formed by several layers and fitted on the left and right sides of the input shaft 1. At an end opposite to the input end of the input shaft 1 is fitted a reverse gear 40 which engages an idler gear 41 which engages a mounting shaft 43 through a bearing. The mounting shaft protrudes beyond the housing 10 to be fixed by a nut 44. At the input end and the other end of the input shaft are disposed bearings 11,12 associated with the housing 10 at an inner lower portion thereof. The driven gear assembly 6 includes four driven gear sleeves 64, 63, 62, 61 and a driven gear 65 with increasing diameters. The combined number of the driven gear and sleeves also equals that of the ratios. The driven gear sleeves are telescoped on the driven shaft 5 corresponding to the driving gear assembly. The other end of the driven shaft 5 engages an output shaft 9 and the driven shaft 5 is disposed at an inner upper portion of the housing 10 in parallel to the input shaft 1. The driven shaft 5 supports a driven fifth-ratio gear 65 which is engaged with the driven shaft 5 by a key 651. The teeth of the driven fifth-ratio gear 65 mesh with the teeth of the driving fifth-ratio gear sleeve 25. The driven shaft 5 is sleeved by a driven fourth-ratio spring 641 which is sleeved by a driven fourth gear sleeve 64 which is sleeved by a driven third-ratio spring 631 which is sleeved by a driven third-ratio gear sleeve 63 which is sleeved by a driven second-ratio spring 621 which is sleeved by a driven second-ratio gear sleeve 62 which is sleeved by a driven first-ratio spring 611 which is finally sleeved by a driven first-ratio gear sleeve 61. Each driven shift spring is not directly closely fitted on each driven shift gear sleeve. Each driven shift gear sleeve engages a bearing 612,622,632, 642 at one end and engages a bearing 613, 623, 633, 643 at the other end. The teeth of each driven ratio gear sleeve and gear mesh with the teeth of each corresponding driving shift gear sleeve. The driven gear assembly 6 is mounted in the housing 10 by a bearing 51. The forward/reverse/neutral shift control assembly 7 is connected to a shifting disk 72 by a manual control lever 71 extending into the housing 10 and fitted to one end of the driven shaft 5 near the driven gear assembly 6. The control assembly 7 is further connected with a forward/reverse gear engaging disk 73 at the other end of the shifting disk and is fitted to the driven shaft 5 by two layers of slide sleeves. The inner layer is a forward gear slide sleeve 75 which is sleeved by a forward gear slide sleeve torque spring 751 located between a flange of the forward gear slide sleeve and a forward gear sleeve 81. One end of the forward gear slide sleeve 75 is connected to a reverse gear slide sleeve 74 of outer layer by a bearing 752. The reverse gear slide sleeve 74 is sleeved by a reverse gear slide sleeve torque spring 741 located between a flange of the reverse gear slide sleeve and a reverse gear sleeve 82. One end of the reverse gear slide sleeve is connected with the housing 10 by a bearing 742. The forward/reverse gear assembly 8 is connected with the forward/reverse/neutral shift control assembly 7. The forward/reverse gear assembly 8 is formed by two layers of gear sleeves. The inner layer is a forward gear sleeve 81 and a forward gear spring 811 is fitted therein. The forward gear spring 811 is not directly closely fitted on the driven shaft. The forward gear sleeve is connected with the housing 10 by a bearing 812 near the output shaft 9 and is connected with the driven shaft by a bearing 813. The thickness of the forward gear spring corresponds to that of the forward gear slide sleeve, and the thickness of the forward gear sleeve corresponds to that of the forward gear slide sleeve torque spring. The forward gear sleeve is sleeved by a reverse gear sleeve 82 and a reverse gear spring 821 is fitted therein and is not directly closely fitted on the forward gear sleeve. The reverse gear sleeve is connected with the housing 10 by a bearing 822 near the output shaft. The thickness of the reverse gear spring corresponds to that of the reverse gear slide sleeve and the thickness of the reverse gear sleeve corresponds to that of the reverse gear slide sleeve torque spring. The teeth of the reverse gear sleeve mesh with the teeth of the idler gear and the driven shaft 5 is screwed to the output shaft 9 at one end of the forward gear sleeve. The output shaft is mounted in the housing 10 by a bearing 9 and extends outside the housing 10 for driving. As shown in Fig.2, the primary structure of this embodiment of the invention is illustrated. The input shaft 1 is loosely sleeved by the driving first-ratio spring 211 which is sleeved by the driving first-ratio gear sleeve 21. A clearance therefore exists between the driving first-ratio spring and input shaft. The driving first-ratio spring is kept in a loose state and one end thereof is fixed on a toothed end of the inner surface of the driving first-ratio gear sleeve at position 213. Each gear sleeve is generally formed with an extending gear tooth portion inner side of which is associated with a ball bearing. Therefore, the gear tooth end is pivoted to the input shaft by a bearing 212 and the other end thereof is fitted to a driving first-ratio slide sleeve 34 located on the input shaft. One end of the slide sleeve 34 has a flange 343 the thickness of which equals that of the driving first-ratio gear sleeve. Between the outer end of the driving first-ratio gear sleeve and the flange of the driving first-ratio slide sleeve is disposed a driving first-ratio slide sleeve torque spring 341. A slot 344 is formed on the proper portion of the driving first-ratio slide sleeve. The slot 344 corresponds to a projection 101 on the input shaft, permitting the slide sleeve to slide over a certain distance. The lower end edge of the slide sleeve has a recess 345 which can receive the other end 215 of the driving first-ratio spring. Fig.2 shows that the slide sleeve is not engaged with the spring and the projection on the input shaft is located in the slot of the slide sleeve near the spring to only drive the slide sleeve, making the same rotate together with the input shaft. Fig.3 shows that the driving first shift slide sleeve is forced to move towards the driving first-ratio spring end 215, making the spring end 215 go into the recess 345 of the slide sleeve and press the driving first-ratio spring. Because the input shaft is rotated, making the driving first-ratio slide sleeve rotate in the same direction and the driving first-ratio spring is pressed to closely engage with the output shaft, the driving first-ratio spring will rotate in the same direction, and because the other end of the driving first-ratio spring is engaged with the driving first-ratio gear sleeve, the driving first-ratio gear sleeve will also rotate in same direction. The projection 101 of the input shaft engages with the slot of the slide sleeve away from the spring. When not forced, the restoring force of the driving first-ratio slide sleeve torque spring 341 will restore the sleeve. At this time, only the projection drives the slide sleeve to rotate in the same direction. Because the driving first-ratio spring is not forced to engage with the input shaft, therefore the driving first-ratio spring and driving first-ratio gear sleeve both will not rotate following the input shaft. This is the character of this embodiment of the present invention. The driving gear assembly and forward/reverse gear assembly are disposed according to the same principle. In Fig.4, the forward gear control assembly 3 is partially shown. A five forward ratio engaging disk 33 is connected with a shifting gear disk 32. The teeth of the shifting gear disk mesh with the thread of a threaded rod 31. The threaded rod is controllably rotated by a stepping motor 311 which is controlled by a microprocessor 312 which controls the torque output to guide the threaded rod to rotate and make the gear-shifting disk 33 rotate. The microprocessor has many detecting measuring devices respectively connected with the input shaft, output shaft, accelerator, carburettor, brake disk and clutch to feed back various state data to the microprocessor for calculating the best present rotating speed data and determining the gear ratio and sending to the stepping motor for execution. Fig.4 shows a neutral state wherein the gear-shifting disk is fitted to the input shaft 1. Two sides of the gear-shifting disk are formed with five different shifting slots 321,322,323,324, 325. The five pairs of shifting slots respectively receive engaging keys 331, 332,333,334,335 of the forward ratio engaging disk. The five pairs of shifting slots are formed in the rotating direction of the gear and the interval therebetween is about 20 degrees. The first shift slot 321 is located at zero degrees, engaging with a first shift engaging key 331, and the second shift slot 322 is located within zero degrees to 20 degrees, engaging with a second shift engaging key 332, and the third shift slot 323 is located within zero degrees to 40 degrees, engaging with a third shift engaging key 333, and the fourth shift slot 324 is located within zero degrees to 60 degrees, engaging with a fourth shift engaging key 334, and the fifth shift slot 325 is located within zero degrees to 80 degrees, engaging with a fifth shift engaging key 335. The left keys will go upward and the right keys will go downward. On the engaging disk, two corresponding keys are located respectively at zero degrees and 180 degrees positions. If the stepping motor 311 forces the threaded rod to rotate the gear-shifting disk, a state as in Fig.5 will be achieved wherein the first shift engaging key 331 slides away from the first shift slot 321 and the other second, third, fourth and fifth shift engaging keys are located in the second, third, fourth and fifth shift slots. But the engaging disk will not rotate and only the gear-shifting disk will rotate about 20 degrees. When changing from original neutral gear to first gear, the first-ratio engaging key will make the first-ratio slide sleeve move. This is the working state of auto-shifting. Therefore, the microprocessor can be used to choose optimum shift to maximize the engine effect. Fig. 6 shows the transmission in operation in first gear. The stepping motor 311 in Fig.5 has driven the threaded rod 31, making the gear-shifting disk 32 rotate through a certain angle to therefore make one end of the first-ratio engaging key 331 slide out of the first-ratio slot 321 of the gear-shifting disk 32 and make the other end thereof pressed towards the flange of the driving first-ratio slide sleeve 34 and make the flange of the driving first-ratio slide sleeve further pressed towards the driving first-ratio slide sleeve torque spring 341. The recess of the driving first-ratio slide sleeve at this time engages with the projecting end of the driving first-ratio spring 211, making the same closely fitted on the input shaft 1 and carried by the input shaft to rotate in the same direction at the same speed. Also, the driving first-ratio gear sleeve 21 engaging with the driving first-ratio spring 341 will rotate together therewith in the same direction. Since the driving first-ratio slide sleeve 34 is engaged with the projection and rotates in the same direction, therefore it will rotate at a speed identical to that of the input shaft 1, making the driving first-ratio gear sleeve 21 rotate at the same speed. Because the driving first-ratio gear sleeve 21 will make driven first-ratio gear sleeve 61 rotate in the reverse direction and one end of the driven first-ratio spring 611 engages with the driven first-ratio gear sleeve, therefore the driven first-ratio spring will be closely fitted on the driven second-ratio gear sleeve 62, making the driven first-ratio spring drive the driven second-ratio gear sleeve to rotate in the reverse direction and make the driven second-ratio spring 621 rotate in the reverse direction to be closely fitted on the driven third-ratio gear sleeve 63, making the driven third-ratio gear sleeve rotate in the reverse direction to drive the driven third-ratio spring 631 to reversely rotate to be closely twisted on the driven fourth-ratio gear sleeve 64, making the driven fourth-ratio gear sleeve rotate reversely to drive the driven fourth-ratio spring 641 to be twisted on the driven fifth-ratio gear 65, making the driven fifth-ratio gear rotate reversely. Finally, an engaging key of the driven fifth-ratio gear engages the driven shaft to drive the driven shaft to rotate in the reverse direction. However, a tooth number ratio exists between the driving gear set and driven gear set. Therefore, the speeds of the input shaft and the driven shaft can be identical or different. Since the driving and driven second-, third- and fourth-gear sleeves and the fifth-ratio gear mesh with each other, therefore the driven-ratio gear sleeve and gear can make the driving-ratio gear sleeve rotate. But the driving-ratio springs engaging with the driving-ratio gear sleeves are not twisted on the higher ratio gear sleeve. Therefore, the driving ratio gear sleeves rotate in same direction as the input shaft. But the driving ratio gear sleeves will rotate individually as an idling state which will not affect the rotation of the driving first-ratio gear sleeve and the driven gear set. The power will be sent from the driving first ratio to the driven first ratio and to the output shaft. Fig. 7 shows the transmission operating in third gear. The stepping motor 311 drives the threaded rod 31, making the gear-shifting disk 32 rotate through another angle. At this time, the second engaging key 332 will slide out of the second-ratio slot 322 to form the second gear state. The threaded rod can further rotate through another angle from the second zone angle to the third zone angle. At this time, the third-ratio engaging key 333 will slide out of the third-ratio slot 323 to form the third gear state. At this position, the first-, second- and third-ratio engaging keys 331,332,333 all slide out of the first, second and third slots 321,322,323 as shown in Fig.8. Therefore, the three engaging keys engage with the flanges of the driving first-, second- and third-ratio slide sleeves 38,37,36 to make the driving first-, second- and third-ratio slide sleeve torque springs 381,371,361 forced and pressed and make the driving first-, second- and third-ratio slide sleeves pressed towards the driving first-, second- and third-ratio springs 211,221,231 and make the same respectively twisted on the surfaces of the input shaft 1, driving first-ratio gear sleeve 21 and driving second-ratio gear sleeve 22 so that the input shaft will drive all first-, second- and third-ratio gear sleeves 21,22,23 to rotate in the same direction at the same speed. However, since the driving second-ratio spring engages driving first-ratio gear sleeve and also experiences the rotating force of the driving first gear, therefore the driving second-ratio gear sleeve will have a rotating speed of the driving first-ratio gear sleeve in addition to the original input shaft speed. Thus, the driving third gear will have driving first-ratio gear sleeve rotating speed and driving second-ratio gear sleeve rotating speed in addition to the input shaft rotating speed. Since the teeth of the driving gear set mesh with the teeth of the driven gear set, thereby a rotating speed output from the driving third-ratio gear sleeve to the driven gear set is obtained to make the driven gear sleeves 61, 62,63 and 64 and driven gear 65 rotate reversely and the driven first-, second-, third- and fourth-ratio springs 611, 621,631,641 also respectively are twisted on the driven second-, third- and fourth-ratio gear sleeves and the driven shaft 5, and the driven fifth ratio gear is engaged with the driving shaft to make the rotating speed of the driven first- and second-ratio gear sleeves sent from the driving first- and second-ratio gear sleeves smaller than the rotating speed sent from the driving third-ratio gear sleeve towards the driven third-ratio gear sleeve. Therefore, only the driven third-ratio spring is closely forced on the driven fourth-ratio gear sleeve to make the driven fourth-ratio gear sleeve rotate, and because the driven fourth-ratio spring engaging with the driven fourth gear sleeve is closely forced on the driven fifth-ratio gear to make the same rotate and because the driven fifth ratio gear engages with the driven shaft, the driven shaft is driven to rotate at the speed of the driven third ratio. Because the driving fourth- and fifth-ratio springs are not closely twisted on the driving fourth- and fifth-ratio gear sleeves and because the fourth-and fifth-ratio engaging keys do not press down the driving fourth- and fifth-ratio slide sleeves to engage with the driving fourth- and fifth-ratio springs, therefore the driving fourth- and fifth-ratio gear sleeves will only drive the driving fourth- and fifth-ratio springs to rotate following the driven fourth and fifth ratios at a speed sent therefrom but will not actually drive to form an idling state. The second- and fourth-ratio transmission states are like the third-ratio state and will not be described in detail hereinafter. Of course a tooth number ratio exists between the driving third and the driven third ratio and thus the speed of the driven third ratio is different from that of driving third ratio. Fig.9 shows the transmission in operation in fifth gear, wherein the stepping motor 311 has driven the threaded rod 31, making the gear-shifting disk 32 further rotate through another angle to make five ratio-engaging keys 331, 332, 333,334,335 all slide out of the slots 321,322,323,324,325 of the gear-shifting disk 32. As shown in Fig.10, the five keys respectively move the driving first-, second-, third-, fourth- and fifth-ratio slide sleeves 38,37,36,35,34 making the driving first-, second-, third-, fourth- and fifth-ratio slide sleeve torque springs 381, 371, 361, 351, 341 pressed. At this time, the driving first-, second-, third-, fourth- and fifth-ratio slide sleeves 38,37,36,35, 34 are respectively fitted to the driving first-, second-, third-, fourth- and fifth-ratio springs 211,212,213,214,215, making the driving first-, second-, third-, fourth- and fifth-ratio gear sleeves 21,22,23,24,25 rotate following the input shaft 1 in the same direction. Because the rotating speeds of the driving ratio gear sleeves are different from one another, and since inside the driving fifth-ratio gear sleeve, the driving fifth-ratio spring is twisted on the driving fourth-ratio gear sleeve and the driving fourth-ratio spring is twisted on the driving third-ratio gear sleeve and at the same time, the driving third-ratio spring is also twisted on the driving second-ratio gear sleeve and the driving second-ratio spring is twisted on the driving first-ratio gear sleeve and the driving first-ratio gear sleeve is twisted on the input shaft, therefore of all the driving-ratio gear sleeves, the fifth-ratio gear sleeve has the fastest speed, the fourth one has the second-fastest speed, the third one has the third-fastest speed, the second one has the fourth-fastest speed and the first one has the slowest speed. The speeds of the input shaft and driving first- to fifth-ratio gear sleeves all are sent to the driven first- to fourth-ratio gear sleeves and the fifth gear according to the tooth-number ratio between the driving- and driven-ratio gear sleeves. Therefore, the driven fifth-ratio gear has the fastest speed and since the driven fifth-ratio gear is directly engaged with the driven shaft, thus it will transmit directly the speed to the driven shaft, and the speeds of the driven fourth, third, second and first ratios are gradually reduced. Thus, the driven fourth-, third-, second- and first-ratio, springs can-not be closely twisted on the driven fifth gear and the fourth-, third- and second-ratio gear sleeves to form an idling-like state without actual driving. This is the fifth-ratio transmission. The ratio can be increased or reduced according to the same principle. According to the above description, when the accelerator is depressed and the power input from engine becomes larger and larger, the data sent from the detecting points to the microprocessor also becomes larger and larger, and the instruction sent from the microprocessor to the stepping motor also becomes quicker and quicker. Thus, the threaded rod will make the gear-shifting disk rotate through an angle and another angle, making the engaging keys one by one slide out of the slots to press driving ratio slide sleeves to engage with the driving shift springs, making the driving ratio gear sleeve driven by the input shaft rotate at different speeds which increase from first gear to fifth gear. Therefore, the rotating speed transmitted to the driven shaft also increases gradually and the rotating speed of the output shaft will thus increase gradually. However, a common real road condition will not be so smooth and downward changes are necessary. Thereby, when the data sent to the microprocessor become small to indicate that the accelerator is free or the brake pedal is depressed and the speed is reduced, the microprocessor will output a signal to the stepping motor, making the same reversely rotate to drive the threaded rod, making the gear-shifting disk rotate reversely, making the engaging keys free from separating force and experience a restoring force. The engaging keys will no more press the driving ratio slide sleeves and the pressed driving ratio slide sleeve torque springs will extend to their original state. Also, the engaging keys will rebound into the slots of the gear-shifting disk, and the driving ratio slide sleeve will no more engage with the driving ratio springs and rebound to its original position, and the driving shift springs also no more be twisted on the driving shift gear sleeve or input shaft and will restore one ratio by one ratio to also make the driven ratio gear sleeves and gear rotate at gradually reduced speed ratio by ratio. Thus, the neutral state can be achieved. Or, the ratio position can be changed to the lower ratio and then raised to the higher ratio according to external conditions. Fig.11-1 shows a sectional view of the forward/reverse/neutral control assembly 7, wherein the neutral condition is illustrated. The transmission is connected to an external manual control lever 71 which is connected to a shifting disk 72. The shifting disk 72 is fitted on the driven shaft 5. Two pairs of slots are respectively formed on upper and lower sides of the shifting disk 72. The outer one is a reverse gear slot 721. The upper reverse gear slot faces right and the lower one faces left. In the reverse gear slot is disposed a reverse gear engaging key 731. The size of the reverse gear slot is about two to three times that of the engaging key. The inner slot is forward gear slot 726 which is under the reverse gear slot 721. If the upper reverse gear slot 721 faces left, then the forward gear slot 726 faces right. Moreover, the slot 726 located under forward gear is formed above the reverse gear slot 721. If the lower reverse gear slot 721 faces right, then the forward gear slot 726 faces left. The size of each forward gear slot is also about two to three times that of the engaging key. When in neutral, the manual control lever and forward gear engaging key and reverse gear engaging key are aligned with one another, i.e., the forward gear and reverse gear engaging keys respectively are located in the forward gear and reverse gear slots. Fig. 11-2 shows the forward/reverse/neutral shift control assembly 7 in the reverse gear condition, wherein the manual control lever 71 is turned left through a certain angle, making the reverse gear engaging key 731 separate from the reverse gear slot 721 and the forward gear engaging key 736 remain in the forward gear slot 726 and only move from one end to the other end. Fig. 11-3 shows the control assembly 7 in the forward gear condition. At this time, the manual control lever 71 is turned right through a certain angle, making the forward gear engaging key 736 separate from the forward gear slot 726 and the reverse gear engaging key 731 remain in the reverse gear slot 721 and only move from one end to the other end. A control button can be used to control the stepping motor and threaded rod to drive the forward/reverse gear disk to move without using a manual shifting lever. When under forward first, third and fifth ratio positions as shown in Figs. 6, 8, 10 and when the manual control lever is shifted to the forward gear position as shown in Fig. 11-3, the forward gear engaging key 731 slides out of the forward gear slot towards the forward gear slide sleeve 75 of the assembly 7, making the forward gear slide sleeve slide axially and making the recess thereof engage with the projecting portion of the forward gear spring 811, the rotating speeds of each ratio will be transmitted from the driven shaft. The forward gear spring twisted on the driven shaft will drive the forward gear sleeve to rotate at the same speed and in the same direction as the driven shaft. Since the forward gear sleeve is screwed on the output shaft, therefore the output shaft will output corresponding to the speed and direction of the driven shaft under each gear position. But the output shaft will rotate in a reverse direction of the rotating direction of the input shaft. Through the output shaft, the engine transmits power outwardly to move forwards. At this time, the reverse gear is located in outer layer and not twisted tightly and will not produce any effect. Fig. 12 shows the transmission in the reverse gear condition, wherein the manual control lever is shifted to the reverse position as shown in Fig. 11-2 and the reverse gear engaging key 736 slides out of the reverse gear slot to press the reverse gear slide sleeve 74 of assembly 7, making the reverse gear slide sleeve axially slide to press the reverse gear slide sleeve torque spring 741, making the recess of the reverse gear slide sleeve engage with the projecting portion of the reverse gear spring 821, making the reverse gear spring twist closely on the forward gear sleeve 75 to drive the forward gear sleeve to rotate, and since the forward gear sleeve is screwed on the output shaft, the output shaft is also driven to rotate. The power is obtained in such a manner that the teeth of the reverse gear sleeve mesh with the teeth of the idler gear 41 and the teeth of idler gear further mesh with the teeth of the reverse gear 40 fitted to the input shaft 1 so that the reverse gear sleeve rotates in same direction as the input shaft and the idler gear rotates in different direction from the input shaft. Therefore, the reverse gear sleeve rotates in same direction as the input shaft while the forward gear sleeve rotates in same direction as the input shaft and the power is transmitted from input shaft toward output shaft to produce a reversing effect. The differences between the aforesaid forward gear and this effect are the power transmitting path and direction and value. Therefore, the forward and reverse gears are both controlled by the manual control lever. When moving forwards, it will never reverse and when reversing, it will never advance to keep the driving smooth and safe. The housing of this transmission is disposed according to each element. Because it pertains to totally meshing system and is supported by bearings to rotate, the elements all rotate at high speed during a long period, and heat is produced by frictional motion and a lubricating and cooling device is required. in the present invention, an oil pool is disposed under the housing and partial gears are immersed therein so that when rotating, a lubricating and cooling effect is obtained. Fig. 13 shows another embodiment of input shaft portion of this invention. A gear sleeve 21 is fitted on the input shaft 1. The upper end of the gear sleeve 21 has a gear portion. The whole sleeve 21 is integrally made. The gear portion extends beyond the outer surface of the sleeve 21. On the inner surface of the gear sleeve 21 is disposed a bearing 212. The other end of the sleeve 21 engages with one end of a spring 211. The other end of the spring has a tapered portion 2111 with a reduced outer diameter. A projection 101 is formed on the input shaft and a slide sleeve 34 is fitted to the other end of the input shaft. The slide sleeve has a flange 343. A torque spring 341 is disposed between the flange and the gear sleeve end. A slot 344 is formed on the slide sleeve. The projection 10 is located at one end of the slot. In Fig. 13, the slide sleeve is not forced to slide towards the gear sleeve. In Fig. 14, the slide sleeve 34 is forced to slide towards the gear sleeve 21 and the torque spring 341 retracts and the projection 101 slides in the slot 344 from one end to the other end. At this time, since the projection 101 engages the slide sleeve and the input shaft rotates to drive the slide sleeve to rotate, when the slide sleeve slides towards the spring, it will engage the spring 211. The inner rear end of the slide sleeve has a tapered inner surface portion 347 which can more closely engage with the tapered portion 2111 of the spring, making the spring closely twisted on the input shaft to be driven to further rotationally drive the gear sleeve. When not forced, the slide sleeve will be urged to its original position by the torque spring. The spring will become loose and no longer drive. The outer several gear sleeves are all provided with the projections and same elements. Figs. 15 and 16 show a further embodiment of the input shaft portion, wherein a gear sleeve 21 is fitted on the input shaft 1. The gear sleeve has a gear portion at its one end and is formed integrally. The gear portion extends beyond the outer surface of the gear sleeve. The gear sleeve is provided with a bearing 212 near its gear portion end and a recess 215 at its rear end. A slide sleeve 34 is fitted on the other end of the input shaft 1. The slide sleeve has a projecting portion 345 at its rear end and the input shaft ha a projection 101. A slot 344 is formed on the slide sleeve to receive the projection 101 at its one end. At other end of the slide sleeve are disposed two flanges 343, 346 between which a sleeve neck 347 is received. An engaging key projecting end 331 can be disposed in the sleeve neck of the slide sleeve to drive the slide sleeve. Fig. 15 shows that the slide sleeve is not engaged with the gear sleeve. In Fig. 16, the projecting end 331 of the engaging key drives the slide sleeve to slide towards the gear sleeve, making the recess 215 of the gear sleeve engage with projecting portion 345 and the projection of input shaft slide towards the other end. At this time, the input shaft rotates to drive the slide sleeve 34 to rotate and further drive the gear sleeve 21 to rotate. When the projecting end 331 of engaging key is taken back, the slide sleeve slides back too. At this time, only the slide sleeve rotates and no driving effect is produced. The outer several layers are also provided with same elements. Fig. 17 shows another embodiment of the input shaft portion of this invention, wherein a gear sleeve 21 is fitted on the input shaft 1 and a spring 211 is disposed whereby, when the spring 211 is twisted, the inner diameter thereof is larger than the outer diameter of the input shaft so that it can be fitted on the input shaft. When the external torque disappears, the resistant restoring torque of the spring will reduce the inner diameter to closely engage with the input shaft. One end of the spring is formed with a triangular projection 2113 and one end of the gear sleeve 21 is integrally formed with a gear 216. The inner diameter of the gear sleeve is slightly larger than the outer diameters of the spring 211 and slide sleeve 34. A recess 217 is formed on inner surface near the gear end for a projecting end 2112 of the spring to engage with to restrict the spring so that the spring can only perform a screwing movement. Moreover, the slide sleeve 34 has a substantially triangular projecting end 348 at its one end and has a annular groove 347 receiving a ring member 343 which includes two semicircular members each having a projection 3431 formed with a hole 3432. A screw 3434 goes through the holes 3432 to rotatably fix the ring member 343 on the annular groove 347 of the slide sleeve 34. A projection 349 is suitable to be placed into a slot 218 of the gear sleeve 21. Each semicircular member has a projecting rod 3433 which is moved by the engaging key. A bearing 212 is further disposed at gear end of the gear sleeve. Fig. 18 shows that the ring member 343 is not moved by the engaging key and the triangular projecting end of the slide sleeve 34 engages with the triangular projecting end of the spring to abut against the spring, preventing the same from being twisted closely on the input shaft 1. At this position, the spring will not drive the gear sleeve 21 to rotate, and the projection of the slide sleeve 34 also engages with the slot 218 to prevent the slide sleeve from rotating. Fig. 19 shows that the ring member 343 is outwardly moved by the engaging key to drive the slide sleeve to move outwards, and the projecting end of the slide sleeve no longer engages with the projecting end of the spring. At this time, the projection of slide sleeve slides along the slot 218 of gear sleeve from one end toward the other end. At this position, the spring is free from torque and automatically screws tightly on the input shaft to be driven thereby, and since one end of the spring engages with the gear sleeve, the gear sleeve is also driven to rotate and since the slot of the gear sleeve engages with the projection of the slide sleeve, the slide sleeve is also driven to rotate. At this time, the gear sleeve outputs power outwardly. In this embodiment, the aforesaid gear-shifting disk of the forward gear control assembly operates in reverse directions. The stepping motor outputs power in a reverse direction, making the engaging key slide out of the shifting gear disk. When abutting against the ring member, it is in a neutral condition, and when the engaging key engages with the shifting disk, it is in forward gear, i.e. the original fifth-ratio effect is now neutral and the original fourth ratio is now first ratio and accordingly, the original neutral condition is now fifth ratio. The original forward and reverse gears are now reverse and forward gears. The driving gear set can accordingly form the assembly with several layers.

Claims: A transmission comprising: a housing (10), an input shaft (1) and an output shaft (9); the input shaft having a front half portion and a rear half portion; a driving gear assembly (2) having several driving gear sleeves (21, 22, 23, 24, 25) the number of which is equal to the number of gear ratios of the transmission, the driving gear sleeves having respective different diameters and being fitted on the front half portion of the input shaft in sequence from the smallest diameter one to the largest diameter one, each driving gear sleeve not being permanently rotatably driven by the input shaft; a forward gear control assembly (3) having several slide sleeves (34, 35, 36, 37, 38) with different diameters, the number of which is equal to that of the gear ratios, the slide sleeves being fitted on the rear half portion of the input shaft in sequence from the smallest diameter one to the largest diameter one, a first control means being used to control the engagement and separation of the slide sleeves and corresponding driving gear sleeves to select the gear ratio, each slide sleeve being rotatably driven by the input shaft and being capable of engaging its corresponding driving gear sleeve to cause rotation thereof; a reverse gear assembly (4) having a reversing gear (40) fitted on the rear end of the input shaft, the reversing gear engaging an idler gear (41); a driven shaft (5) having a front portion, a middle portion and a rear portion; a driven gear assembly (6) having several driven gear sleeves (61, 62, 63, 64) and a driven gear (65) the combined number of which is equal to the number of driving gear sleeves, the driven gear sleeves having respective different diameters and being fitted on the front portion of the driven shaft in sequence from the smallest diameter one to the largest diameter one and meshing with respective driving gear sleeves, each driven gear sleeve having a third coupling means (611, 621, 631, 641, 651) which connects the driven gear sleeves with one another and connects the driven gear sleeves with the driven shaft (5) whereby, when each driving gear sleeve rotates, the driven gear sleeve meshing therewith is driven to rotate and rotationally drives in inward sequence each driven gear sleeve and the driven shaft; a forward/reverse gear assembly (8) having two sleeves (81, 82) with different diameters, the sleeves being fitted on the rear portion of the driven shaft in sequence from the smaller diameter one to the larger diameter one, one of the sleeves being a forward drive sleeve, the other of the sleeves being a reverse gear sleeve having a gear which meshes with the idler gear, each sleeve having a fourth coupling means which connects the driven shaft with each sleeve whereby the driven shaft or idler gear can rotationally drive each sleeve; a forward/reverse/neutral control assembly (7) having two slide sleeves (74, 75) with different diameters, the slide sleeves being fitted on the middle portion of the driven shaft with the smaller diameter one within the larger diameter one, a second control means being used to control the separation and engagement of the slide sleeves (74, 75) and the forward/reverse sleeves (81, 82) to select forward or reverse or neutral gear, each slide sleeve (74, 75) rotationally driving a corresponding sleeve (81,82); and the output shaft (9) being connected to the forward/reverse gear assembly. A transmission according to claim 1, wherein the input shaft is connected to an outer control lever means and disposed in the housing (10) on one side thereof, each end of the input shaft extending into the housing and being connected to the housing by a respective bearing (11, 12), an oil inlet being disposed in the housing. A transmission according to claim 1, wherein each driving gear sleeve (21, 22, 23, 24, 25) and driven gear sleeve (61, 62, 63, 64) has a sleeve portion and a gear portion being integrally formed, each gear portion extending outwardly beyond the outer surface of the respective sleeve portion, the gear portions being arranged in sequence and, at the gear end of each gear sleeve, an inner bearing (212, 222, 232, 242, 252, 612, 622, 632, 642) having an oil inlet being provided. A transmission according to claim 3, wherein the gear portions of the driving gear sleeves mesh with the gear portions of the driven gear sleeves in such a manner that the innermost driving gear sleeve (21) meshes with the outermost driven gear sleeve (61), the second innermost driving gear sleeve (22) meshes with the second outermost driven gear sleeve (62), the second outermost driving gear sleeve (24) meshes with the second innermost driven gear sleeve (64) and the outermost driving gear sleeve (25) meshes with the innermost driven gear (65), and the intermediate gear sleeves mesh in a corresponding manner. A transmission according to claim 1, wherein each driving gear sleeve (21, 22, 23, 24, 25) is provided with a first coupling means so that the input shaft can rotationally drive the neighbouring driving gear sleeve (21) and further driving gear sleeves. A transmission according to claim 1, wherein each driven gear sleeve (61, 62, 63, 64) is provided internally with the third coupling means which is a respective spring (611, 621, 631, 641), one end of each spring being engaged in a slot formed near the gear portion of the respective driven gear sleeve and the axially opposite end of each spring extending outwardly whereby the driven gear sleeve can be rotationally driven by rotation of the corresponding driving gear sleeve, making the spring inside the driven gear sleeve tighten on the inwardly-neighbouring driven gear sleeve to rotationally drive the same and, accordingly, the further inner driven gear sleeves are driven in sequence, and when not driven, the spring fits loosely with a clearance on the inner driven gear sleeve. A transmission according to claim 1, wherein each slide sleeve (34, 35, 36, 37, 38) of the forward gear control assembly is provided internally with a second coupling means and the inner surface of one end of each slide sleeve is provided with a bearing formed with an oil inlet. A transmission according to claim 6, wherein the third coupling means for the innermost driven gear (65) is a key (651) located inside the innermost driven gear (65) so that the latter is engaged with the driven shaft by the key so that the innermost driven gear sleeve can directly rotationally drive the driven shaft. A transmission according to claim 1, wherein each driven gear sleeve (61, 62, 63, 64) is provided with a bearing (613, 623, 633, 643) near one end of its sleeve portion to engage with the outer surface of the inwardly-neighbouring driven gear sleeve, the driven gear sleeves being connected to the housing by a bearing (51), each bearing being formed with an oil inlet. A transmission according to claim 5, wherein the first coupling means inside each driving gear sleeve (21, 22, 23, 24, 25) comprises a spring (211, 221, 231, 241, 251), one end of each spring being engaged in a slot (213) formed in the corresponding driving gear sleeve near the gear portion, the other end of each spring extending axially outside the gear sleeve whereby, when not driven, a clearance exists between each spring and the inwardly-neighbouring driving gear sleeve or input shaft and, when driven, the spring is closely tightened on the inwardly-neighbouring driving gear sleeve so that the input shaft or neighbouring driving gear sleeve can rotationally drive the adjacent driving gear sleeve. A transmission according to claim 5, wherein the first coupling means inside each driving gear sleeve (21, 22, 23, 24, 25) comprises a spring (211, 221, 231, 241, 251) one end of which is engaged in a slot (213) formed in the corresponding driving gear sleeve near the gear portion and the other end (2111) of which is tapered whereby, when not driven, a clearance exists between the spring and the inwardly-neighbouring driving gear sleeve or input shaft. A transmission according to claim 10, wherein the other end of each spring (211) has a recess or projection portion (215) whereby, when driven, the recess or projection portion is engaged with a projection portion (345) or recess of the corresponding slide sleeve for rotational driving. A transmission according to claim 5, wherein the first coupling means inside each driving gear sleeve comprises a spring (211,221,231,241,251) the inner diameter of which is smaller than the outer diameter of the inwardly-neighbouring driving gear sleeve or input shaft to be sleeved, whereby when the spring is twisted, it can be fitted thereon, one end (2112) of the spring being engaged with a slot formed on the driving gear sleeve near the gear portion, the other end of the spring having a triangular projecting end (2113), a clearance existing between the spring and the inner surface of the outwardly neighbouring driving gear sleeve. A transmission according to claim 7, wherein the second coupling means for the innermost slide sleeve (34) comprises a projection (101; 349) formed on a predetermined portion of the input shaft to engage with a slot (344; 218) formed in the innermost slide sleeve of the forward gear control assembly whereby the input shaft can rotationally drive the slide sleeve. A transmission according to claim 7, wherein the second coupling means comprises a projection (349) disposed on a predetermined portion of each slide sleeve (34) of the forward gear control assembly, the projection being suitable to engage a slot (344) formed on the neighbouring outer slide sleeve whereby the inner slide sleeve can rotationally drive the outwardly-neighbouring slide sleeve. A transmission according to claim 7, wherein the second coupling means comprises a flange (343) disposed on each slide sleeve and a respective torque spring (341,351,361,371) is disposed between the flange and one end of corresponding driving gear sleeve so that, when the slide sleeve is not driven, it will be urged by the torque spring. A transmission according to claims 7 and 13, wherein the second coupling means comprises a triangular projecting end (348) formed at one end of each slide sleeve (34,35,36,37,38), which is suitable to engage the triangular projecting end (2113) of the spring of the first coupling means of the driving gear sleeve (21), the projecting end (348) of the coupling means being formed with a projection (349) suitable to engage a slot (218) formed in the driving gear sleeve, an annular groove (347) being formed at other end of the slide sleeve, in the annular groove being disposed a ring member formed by two semicircular members (343) each of which has two projecting ends (3431) each formed with a hole (3432), a screw (3434) and a nut being used to go through the holes to fix the ring member in the annular groove of the slide sleeve, each semicircular member having a projection (3433) connected with one end of the first control means to be moved by the forward gear control assembly whereby, when the slide sleeve is driven, it will engage the projecting end of the spring, making the spring not be tightened closely on the inwardly-neighbouring driving gear sleeve to prevent driving and, conversely, when the slide sleeve is pulled back, the spring is tightened closely to drive outer driving gear sleeve. A transmission according to claim 1, wherein the first control means of the forward gear control assembly includes: a microprocessor (312) capable of managing data sent from several detecting means disposed at predetermined positions and outputting action commands after analysis; a stepping motor (311) accepting commands sent from the microprocessor and outputting power according to the commands; a threaded rod (31) driven by the motor to make the forward gear control assembly change the gear position; a ratio-shifting disk (32) having several pairs of shifting slots (321, 322, 323, 324, 325) the number of which is equal to that of the ratios, the slots being radially disposed in such a manner that the inner slot (321) is shorter and the outer slot (325) is larger and all the slots are aligned with one another and symmetrically disposed on two sides of the centre of the disk, the periphery of the gear disk being formed with gear teeth meshing with the thread of the threaded rod to be driven by the threaded rod, the ratio disk further engaging the input shaft (1); an engaging disk (33) engaging the ratio-shifting disk and the input shaft (1), several pairs of engaging slots being formed in the engaging disk symmetrically on two sides thereof; and several pairs of engaging keys (331, 332, 333, 334, 335) suitable for engagement with the slots of the ratio-shifting disk and the slots of the engaging disk whereby, when the ratio-shifting disk rotates, the engaging keys can slide out of or engage with the shifting slots in sequence and engage at their opposite projecting ends to make corresponding slide sleeves engage with or separate from one another, allowing the power of input shaft to be outwardly transmitted from driving gear set. A transmission according to claim 1, wherein the reverse gear of the forward/reverse gear assembly (8) is engaged with the rear half portion of the input shaft (1) by a key and the idler gear (41) is rotatably fixed in the housing (10) by a mounting shaft which (43) is in parallel to the input shaft and fixed in the housing. A transmission according to claim 1, wherein the driven shaft (5) is disposed on the other side of the housing to the input shaft (1), one end of the driven shaft is connected to a bearing (642), an oil passage being formed in the driven shaft, which goes to the oil inlet of the bearing, a clearance existing between the driven shaft and the output shaft (9). A transmission according to claim 1, wherein the second control means of the forward/reverse/neutral shift control assembly includes a manual operating lever (71) extending into the housing, the lever connecting to a shifting disk (72) which is formed with two pairs of shifting slots (721, 726) radially symmetrically disposed on two sides of the centre of the shifting disk, the shifting disk and an engaging disk (73) both being fitted on the middle portion of the driven shaft (5), two pairs of engaging slots being radially symmetrically disposed on two sides of the centre of the engaging disk and two pairs of engaging keys (731, 736) being capable of sliding within the engaging slots and shifting slots whereby the manual operating lever can be used to control forward, neutral and reverse gear position. A transmission according to claim 1, wherein each slide sleeve (74, 75) of the forward/reverse/neutral control assembly has a flange and a torque spring (741, 751) is disposed between the flange and rear end of the corresponding gear sleeve whereby, when the second control means shifts to neutral, the engaging key will not be moved and, when shifting to forward gear, only the inner engaging key slides out to move the flange of the inner slide sleeve (75), making the slide sleeve slide and engage with the forward drive sleeve for driving and, when shifting to reverse gear, only the outer engaging key slides out to move the flange of the outer slide sleeve (74), making the slide sleeve slide and engage with the reverse sleeve gear for driving, and the respective torque springs (741, 751) are used to urge each slide sleeve and engaging key when shifting, the flange end of each slide sleeve being provided with a bearing formed with an oil inlet. A transmission according to claim 1, wherein the inner sleeve of the forward/reverse gear assembly is the forward drive sleeve screwed on the output shaft (9), and the outer sleeve is the reverse gear sleeve (82) meshing with the idler gear (41) and, when in neutral, neither of the inner and outer sleeves are driven. A transmission according to claim 1, wherein the fourth coupling means comprises a respective spring (741, 751) for the inner and the outer sleeves (81, 82), one end of each spring engaging in a recess formed at one end of the respective sleeve on an inner surface thereof, the other end of each spring axially extending out whereby, when in forward gear, the extended end of the spring inside the inner sleeve engages with a recess in inner slide sleeve and is tightened closely on the driven shaft to rotationally drive the inner sleeve and to further rotationally drive the output shaft and, when in reverse gear, the extended end of the spring inside the outer sleeve engages in a recess in the outer slide sleeve and is tightened closely on the inner sleeve, making the outer sleeve through the idler gear rotationally drive the output shaft, making the output shaft output power outwardly. A transmission according to claim 1, wherein each sleeve (81, 82) of the forward/reverse gear assembly is connected to a bearing (822) located on its inner surface at the gear end of the reverse gear sleeve, and is further connected to a bearing (823) located on the outer surface thereof and fixed in the housing, each bearing being formed with an oil inlet. A transmission according to claim 1, wherein an oil-storing means is disposed at the bottom of the housing to lubricate the aforesaid elements and oil passages are formed to communicate the oil-storing means with each element.

Inventors: TSENG SHENG-TSAI, TSENG, SHENG-TSAI
Applicants: TSENG SHENG TSAI, TSENG, SHENG-TSAI
Application year: 1990
Main classification: F16H3
IPC codes: F16H63, F16H3, B60K17