System for a multi-ratio gearbox

Abstract

A system for a multi-ratio gearbox is provided. In one example, a first shaft is coupled to one or more input reduction gear sets. The second shaft is coupled to a multi-range clutch having a first position and a second position to allow two speeds. The third shaft is coupled to the low speed clutch and the fourth shaft is coupled to the high speed clutch to double the speed together. The high speed clutch and the low speed clutch provide large gear dispersion, allowing the multi-range clutch to have reduced gear dispersion, generally reducing the size required for the transmission. A fifth shaft coupled to the fourth shaft via a gear may be an output shaft spaced from the electric motor, resulting in a short flange-to-flange distance.

Description

Technical Field

[0001] The present disclosure relates generally to transmissions and, more particularly, to a symmetrical four-speed transmission for an electric vehicle. Background Art

[0002] The vehicle may include a transmission for controlling the power generated by the engine. The transmission may include one or more shafts and gears that may be engaged or disengaged from each other based on a selected gear ratio.

[0003] A multi-speed power shift transmission of the intermediate shaft type may include a pair of friction clutches and associated gears operably assembled on a speed clutch shaft. The speed clutch shaft is supported near its ends by bearings carried in the end walls of the transmission housing. In a transmission having an equal number of forward speed ratios and reverse speed ratios, the power input to the shaft is provided by a forward clutch and a reverse clutch assembled on an input shaft, which is also supported by bearings in the housing end walls. The gear on the forward clutch adjacent to one housing end wall drives the gear on the speed clutch shaft, and the gear on the reverse clutch adjacent to the other housing end wall drives to another gear on the speed clutch shaft through a reverse idler gear. The reverse idler gear is carried on its own intermediate shaft. Thus, by alternately engaging the forward clutch and the reverse clutch, the speed clutch shaft can be driven in the forward direction or the reverse direction. Each of the pair of speed ratio clutches has a drive gear that meshes with a corresponding driven gear on the power output shaft in a determined ratio relationship. Due to the different selection of the pitch diameters of the speed ratio gears of the two speed clutches, two output shaft speeds are selectively available.

[0004] The inventors have recognized various problems with this approach. For example, if more than two speed ratios are required, such as four speeds in each direction, additional speed clutch shafts may be provided, as well as additional bearings, gears, and the necessary fluid pressure transfer system. The additional number of components such as gears, shafts, and bearings, and the increased complexity and size of the housing when providing additional bearing holes and pressure fluid manifolds and passages, can result in an overly large package and increased weight, to name just a few of the problems. Large packages such as those described may not be suitable for certain vehicle platforms, such as those that require a small distance between output interfaces (e.g., flanges) for installation. Utility Model Content

[0005] In one embodiment, the solution disclosed herein provides a system for a multi-ratio transmission, the system comprising a first shaft coupled to one or more input reduction gear sets, a second shaft coupled to a multi-range clutch, a third shaft coupled to a low-speed clutch, a fourth shaft coupled to a high-speed clutch, and a fifth shaft coupled to an output interface. In one example, the shafts, gears, and clutches described herein allow for four speed ratios with relatively large dispersion between the high-speed clutch and the low-speed clutch while maintaining reduced gear dispersion between the multi-range clutch positions. This reduced gear dispersion between the multi-range clutches can provide more equal (and relatively smaller) gear sizes and lower gear / shaft speeds.

[0006] In addition, the fifth shaft, which is an output shaft, is spaced apart from the fourth shaft by a gear coupling the fifth shaft to the fourth shaft. Spacing the fifth shaft apart from the other shafts allows for a short distance between the output interfaces when the output interfaces are coupled to a shaft that is also coupled to the clutch, as compared to the distance between the output interfaces. The short distance between the output interfaces allows the transmission to be used in vehicle platforms that require short-distance installation. Overall, the transmission having the provided layout is reduced in size, which advantageously allows the transmission to be used in a small installation space.

[0007] In addition, one or more input reduction gear sets included in the transmission allow for reduced output speed and reduced speeds of the second, third, and fourth shafts. The reduced speeds in turn reduce the load levels circulating through the multi-ratio transmission. Lower load levels result in smaller, and therefore more compact, components, thereby reducing the overall size of the transmission.

[0008] It should be understood that the above utility model summary is provided to introduce a selection of concepts further described in the detailed description in a simplified form. It is not meant to identify key or essential features of the claimed subject matter, and the scope of the claimed subject matter is uniquely defined by the claims following the detailed description. In addition, the claimed subject matter is not limited to implementations that solve any disadvantages noted above or in any part of this disclosure. BRIEF DESCRIPTION OF THE DRAWINGS

[0009] Figure 1 A schematic diagram of an exemplary vehicle is shown.

[0010] Figure 2A A schematic diagram of a four-speed transmission system is shown.

[0011] Figure 2B The shifting strategy of a four-speed transmission system is shown.

[0012] Figure 3A A schematic diagram of a four speed transmission system and its power path is shown in a first gear / clutch ratio.

[0013] Figure 3B A schematic diagram of a four speed transmission system and its power path is shown in a second gear / clutch ratio.

[0014] Figure 3C A schematic diagram of a four speed transmission system and its power path is shown in third gear / clutch ratio.

[0015] Figure 3D A schematic diagram of a four speed transmission system and its power paths is shown in fourth gear / clutch ratio.

[0016] Figure 4 A detailed schematic diagram of a transmission case for a four speed transmission system is shown.

[0017] Figure 5 A timing diagram of a use case scenario for a four speed transmission system is shown. DETAILED DESCRIPTION

[0018] A transmission system with two or more selectable different gear ratios is described herein. In one embodiment, the transmission system can be a four-speed transmission including a multi-ratio gearbox. In addition, the transmission system can be an intermediate shaft power shift transmission. The compact layout of multiple shafts, gears and clutches in the system allows the system to achieve a greater selection of gear ratios without unduly affecting the space efficiency of the system. Adding gears to space the output shaft from other gears and shafts can allow integration into vehicle platforms that require long drops and short distances between output interfaces. Additional clutches are intended to modify the power path of the system to increase additional available speeds.

[0019] In one embodiment, the system disclosed herein provides a transmission housing including a symmetrical four-speed schematic diagram with the same number of forward drive gears and reverse drive gears. The first shaft of the plurality of shafts can be coupled to one or more input reduction gear sets. The second shaft of the plurality of shafts can be coupled to a multi-range clutch. The third shaft of the plurality of shafts can be coupled to a low-speed clutch. The fourth shaft of the plurality of shafts can be coupled to a high-speed clutch. The fifth shaft of the plurality of shafts can be coupled to at least two output interfaces. The gear that couples the fourth shaft to the fifth shaft separates the fifth shaft from the fourth gear. The transmission system can include three sections, the first section being (one or more) input reduction gear sets, the second section being a multi-range clutch, and the third section being a low-speed clutch and a high-speed clutch. This can provide a high / low range shift that reduces the gear dispersion required in the second section of the gearbox. The reduced gear dispersion requirement can result in more equal gear sizes and lower gear / shaft speeds. In the case where four speeds are available, an additional gear set can be coupled to the fourth gear to increase the drop. Due to the long drop, the output shaft can be shortened, resulting in a shorter distance between the output interfaces compared to a gearbox where the output interface is coupled to a shaft including a clutch. The pinion size obviously benefits the overall required installation space. The increased drop is beneficial for specific vehicle platforms that require a short flange to flange distance for installation.

[0020] Figure 1-4An example configuration with relative positioning of various components is shown. If shown as directly contacting or directly connected to each other, such elements can be referred to as directly contacting or directly connected, respectively, at least in one example. Similarly, at least in one example, elements shown as continuous or adjacent to each other can be respectively continuous or adjacent to each other. As an example, components placed as face-shared contact with each other can be referred to as face-shared contact. As another example, in at least one example, elements positioned to be spaced apart from each other with only a spacing space between them and no other components can be referred to as such. As another example, elements shown as above / below each other, on opposite sides of each other, or on the left / right of each other can be referred to as such relative to each other. In addition, as shown in the accompanying drawings, in at least one example, the topmost element or the point position of the element can be referred to as the "top" of the component, and the bottommost element or the point position of the element can be referred to as the "bottom" of the component. As used herein, top / bottom, upper / lower, above / below can be relative to the vertical axis of the accompanying drawings and used to describe the positioning of the elements of the accompanying drawings relative to each other. Therefore, in one example, the element shown as above other elements is vertically positioned above the other elements. As yet another example, the shapes of elements depicted in the accompanying drawings may be referred to as having such shapes (e.g., such as rounded, straight, planar, curved, rounded, chamfered, angled, etc.). Additionally, in at least one example, elements shown as intersecting each other may be referred to as intersecting elements or intersecting each other. Further, in one example, an element shown as being within another element or outside another element may be referred to as such.

[0021] Now turning to the attached figure, Figure 1 A schematic diagram of a vehicle system 106 that can obtain propulsion power from an electric motor 154 (e.g., a drive motor) is shown. In one embodiment, the electric motor 154 can be a traction motor. The electric motor 154 receives power from a traction battery 158 to provide torque to the rear wheels 155. For example, during braking operation, the electric motor 154 can also operate as a generator to provide power to charge the traction battery 158. It should be understood that although Figure 1 The electric motor 154 is depicted mounted in a rear wheel drive configuration, but other configurations are possible, such as employing the electric motor 154 in a front wheel configuration, or in a configuration where the electric motor is mounted to both the rear wheels 155 and the front wheels 156 .

[0022] The electric motor 154 may include a gearbox integrated therein (to be further described herein). Additionally or alternatively, the electric motor 154 may be coupled to the exterior of the transmission / gearbox housing. The integrated gearbox may include one or more input reduction gear sets. The electric motor 154 may also include at least one clutch. The controller 112 may send a signal to an actuator of the clutch(es) to engage or disengage the clutch(es) to couple or disengage the power transmission from the electric motor 154 to the rear wheels 155 or the front wheels 156. Additionally or alternatively, there may be multiple traction batteries configured to provide power to different drive wheels, wherein the power to the wheels may be directed based on traction at the wheels, driver demand, and other conditions. In one embodiment, the vehicle system 106 includes a symmetrical four-speed schematic diagram in which the number of forward drive speeds and reverse drive speeds is equal.

[0023] The controller 112 may form part of a control system 114. The control system 114 is shown receiving information from a plurality of sensors 116 and sending control signals to a plurality of actuators 181. As one example, the sensors 116 may include sensors such as a battery charge sensor, a clutch activation sensor, etc. As another example, the actuators may include a clutch, etc. The controller 112 may receive input data from the various sensors, process the input data, and in response to the processed input data, trigger the actuators based on programmed instructions or code corresponding to one or more routines.

[0024] Reference now Figure 2A , a schematic diagram of an exemplary transmission system 200 is shown. Figure 2B The shifting strategy of the multi-ratio gearbox of the transmission system 200 is depicted in FIG. Figure 2A and Figure 3A -Axis system is provided in D. The y-axis can be a vertical axis (e.g., parallel to the gravity axis) and / or the x-axis can be a lateral axis (e.g., a horizontal axis). However, in other examples, these axes can have other orientations.

[0025] A total of four gear / clutch ratios are possible, corresponding to the four selectable speeds of the transmission system 200. The first configuration of the system, in Figure 2B , represented as gear / clutch 1, includes the multi-range clutch 207 in the first position 220 and the engaged low speed clutch 230. The second configuration of the system, in Figure 2B 2, including the multi-range clutch 207 in the second position 222 and the engaged low speed clutch 230. The third configuration of the system, in Figure 2B, represented as gear / clutch 3, includes the multi-range clutch 207 in the first position 220 and the engaged high-speed clutch 232. The fourth configuration of the system, in Figure 2B , represented as a gear / clutch ratio 4, including the multi-range clutch 207 in the second position 222 and the high speed clutch 232 engaged.

[0026] In one embodiment, the multi-range clutch 207 may include a friction clutch, and the high-speed clutch 232 and the low-speed clutch 230 may also be friction clutches. As described herein, the friction clutch may include two sets of plates designed to frictionally engage and disengage each other when the clutch is opened and closed. Thus, the multi-range clutch 207 includes four sets of friction plates, two sets for each available position. For example, when the multi-range clutch 207 is in the first position 220, the clutch plate 234 and the clutch plate 205 may be engaged. The friction clutch may provide smooth engagement of the clutch during a shifting operation. In this way, the transmission is able to efficiently power shift between four operating gears. As a result, power interruptions may be reduced, thereby improving transmission performance and customer appeal.

[0027] Electric motor 202 (eg, Figure 1 202) can be coupled to the input side of shaft 224. In some examples, shaft 224 can be a rotor shaft that couples electric motor 202 to other components of transmission system 200, thereby converting power from electric motor 202 into rotational power that can be used for transmission. In one embodiment, electric motor 202 can be an electric traction motor. Shaft 224 receives power from electric motor 202, and shaft 224 in turn transmits power to downstream components. Specifically, shaft 224 can be rotationally coupled to gear 212, which in turn can be coupled to gear 213. Bearings 262 located at either end of shaft 224 can support and facilitate the rotation of shaft 224. Gear 213 can be further coupled to the input side of input shaft 225. A set of gears and shafts including gear 212, gear 213, and input shaft 225 can include a first input reduction gear set 204, which can be a first half of a first section of a gearbox.

[0028] The output side of the input shaft 225 can be further coupled to the gear 214. Bearings 264 located between the gears 213 and 214 at either end of the input shaft 225 and on the axis of the input shaft 225 can support and facilitate the rotation of the input shaft 225. The gear 214 can be further coupled to the gear 215, which can be coupled to the shaft 226. The second set of gears and shafts including the gears 214, 215, and shaft 226 can include a second input reduction gear set 206, which can be the second half of the first section of the gearbox. In some embodiments, the input shaft 225 can be the first shaft of the multi-ratio gearbox described above. The input shaft 225 can extend through the two gears 213 and the gear 214. The gears 213 and the gear 214 can be parallel to each other and coaxial with each other and the input shaft 225.

[0029] Compared to an internal combustion engine, the electric motor 202 can operate at a relatively high speed and can be reduced in speed before entering the transmission system 200. Due to the high transmitted torque and load, relatively large-sized bearings may be required, but these larger bearings may not be able to accept the high speed generated by the electric motor 202. The first input reduction gear set 204 and the second input reduction gear set 206 can reduce the input speed from the electric motor 202 to a speed acceptable to the larger bearings. Therefore, the transmission system 200 allows the bearings to allow high transmitted torque and load, increases the overall usability of the transmission system 200, and allows the components therein to be smaller in size to obtain similar high power levels.

[0030] An embodiment of a method for inputting a reduction gear set is described. An input shaft (e.g., shaft 224) is driven to rotate at an input speed. When two shift elements of the reduction gear set are engaged (e.g., closed according to the shift logic of the gearbox), an output shaft (e.g., input shaft 225) of the reduction gear set rotates at an output speed. The output speed can be lower than the input speed, thereby allowing a high input speed without causing a high output speed.

[0031] The second section of the gearbox may include a second shaft (e.g., shaft 226) and a multi-range clutch 207. The multi-range clutch 207 may allow two different speeds of the transmission system 200. In some embodiments, the multi-range clutch 207 may include a first position 220 that couples the second shaft (e.g., shaft 226) to a third shaft (e.g., shaft 227) via a low gear, and a second position 222 that couples the second shaft to the third shaft via a high gear. When engaged, the first position 220 may be a low gear, and when engaged, the second position 222 may be a high gear.

[0032] In some examples, shaft 226 can be rotationally coupled to gear 216, which is further coupled to multi-range clutch 207. Bearings 268 located at either end of shaft 226 can support and facilitate rotation of shaft 224. Bearings 270 and 272 can further support and facilitate rotation of shaft 226. Bearings 270 and 272 can be located at either side of gear 216, such as Figure 2A As shown. The multi-range clutch 207 can be composed of a set of parallel shafts, which includes two sets of friction clutch plates and two gears. Each of the parallel shafts can include a clutch plate or be otherwise connected to a clutch plate. For example, when the multi-range clutch 207 is in the second position 222, the clutch plate 236 and the clutch plate 203 can be engaged. When the multi-range clutch 207 is in the first position 220, the clutch plate 234 and the clutch plate 205 can be engaged. The clutch plate 234 and the clutch plate 236 can be connected to the gear 209 and the gear 208, respectively. The clutch plate 205 and the clutch plate 203 can be connected to the gear 216. When the gear 216 is actuated by the actuator ( Figure 2A When the gear 216 is shifted to the left by the actuator (not shown), the first position 220 can be engaged. Figure 2A ) is switched to the right side, the second position 222 can be engaged.

[0033] When in the first position 220, the multi-range clutch 207 can generate a relatively lower speed than when in the second position 222. Thus, as described above, the first position 220 can be a low gear and the second position 222 can be a high gear. Thus, the multi-range clutch 207 is capable of generating two of the four potential speeds of the transmission system 200 with reduced dispersion between the gears coupled to the multi-range clutch 207.

[0034] The third section of the gearbox can include a low-speed clutch and a high-speed clutch, which can double the number of speeds of the transmission system 200 in the forward and reverse drive directions, for a total of four speeds in some embodiments. Gear 208 of the multi-range clutch 207 can be coupled to gear 217. Gear 217 can be rotationally coupled to shaft 227, and shaft 227 can be further rotationally coupled to gear 218. Gear 209 of the multi-range clutch 207 can also be coupled to gear 218. Bearing 274 can support and facilitate the rotation of shaft 227. Bearing 274 can be located at either end of shaft 227. Bearing 276 can further support and facilitate the rotation of shaft 227. Bearing 276 can be located in the vertical axis of the low-speed clutch 230 along shaft 227. Gear 218 and gear 217 can be parallel to each other, located on opposite ends of shaft 227, wherein gear 217 faces left relative to the x-axis and gear 218 faces right relative to the x-axis. The shaft 227 may extend horizontally across the gear 217 and the gear 218. The low speed clutch 230 may be coupled to the gear 218 above and below the shaft 227. During conditions in which the low speed clutch 230 is engaged, the low speed clutch 230 may be coupled to the gear 219 via the gear 210. In embodiments in which the low speed clutch 230 is a friction clutch, when engaged, the clutch plates 240 and 242 may be frictionally engaged.

[0035] During conditions where high speed clutch 232 is engaged, gear 218 may further be coupled to high speed clutch 232 via gear 211. In embodiments where the high speed clutch is a friction clutch, clutch plates 244 and clutch plates 246 of high speed clutch 232 may be frictionally engaged when engaged.

[0036] In addition, high-speed clutch 232 can be fixedly coupled to gear 219 above and below shaft 228. Bearings 278 can support and facilitate rotation of shaft 228. Bearings 278 can be located at either end of shaft 228. Bearings 280 can further support and facilitate rotation of shaft 228. Bearings 280 can be located along shaft 228 in the vertical axis of high-speed clutch 232. Gear 219 can be parallel to gear 218 and gear 217, although it can be located vertically below gears 218 and 217. Shaft 228 can be parallel to output shaft 227, output shaft 226, output shaft 224, and input shaft 225.

[0037] In some examples, gear 219 is coupled to gear 229. Gear 229 can be rotatably coupled to output shaft 238. Output shaft 238 can be coupled to two output interfaces 260. Output interface 260 can be positioned at either end of output shaft 238. In some examples, the output interface can be a flange, a yoke, etc. The output interface 260 can be designed to be mechanically attached to a downstream transmission system component, such as a shaft, a joint, etc., which transmits mechanical power to a drive axle (not shown). Prior to the location of the output interface 260, bearings 292 mounted at either end of the output shaft 238 can support and facilitate the rotation of the output shaft 238.

[0038] Gear 229 can allow the output shaft 238 and the output interface 260 to be spaced apart from components vertically above. In the absence of a clutch coupled to the output shaft 238, the distance between the output interfaces 260 can be reduced as would be the case if the output interface 260 was coupled to the shaft 228. The reduced distance between the output interfaces 260 can allow the transmission system 200 to be suitable for vehicle platforms and / or application scenarios that require a small distance, such as a loader type vehicle.

[0039] The second, third, and fourth shafts described herein (e.g., shafts 226, 227, and 228) may be countershafts or speed clutch shafts, such that power is not input from a source but from another shaft, and is not output to an output but to another shaft. For example, the second shaft (e.g., shaft 226) receives power from the input shaft 225 via a plurality of gears, and transmits power to the third shaft (e.g., shaft 227) via a multi-range clutch 207. In this way, the second, third, and fourth shafts provide power transmission through a multi-ratio gearbox, and the directionality of the power transmission is changed by clutch engagement.

[0040] All axes described herein may extend horizontally parallel to the x-axis, and all gears described herein may extend vertically parallel to the y-axis. In some examples, input shaft 225, shaft 226, shaft 227, shaft 228, and output shaft 238 (e.g., first shaft, second shaft, third shaft, fourth shaft, and fifth shaft) may extend through the associated gears or clutches to which they are coupled. In some embodiments, when arranged in a vehicle, a first shaft (e.g., input shaft 225) may be vertically above a second shaft (e.g., shaft 226), a second shaft may be vertically above a third shaft (e.g., shaft 227), a third shaft may be vertically above a fourth shaft (e.g., shaft 228), and a fourth shaft may be vertically above a fifth shaft (e.g., output shaft 238). The first, second, third, fourth, and fifth axes described herein may be parallel to each other, with the fifth axis being vertically below the first, second, third, and fourth axes. Various axes positioned parallel to each other may provide a desired form factor for a transmission housing. Additionally, the parallel architecture allows for more support at bearing locations throughout the transmission.

[0041] All clutches described herein (e.g., multi-range clutches and low and high speed clutches) can be oriented vertically with the vertical top of each clutch above the shaft and the vertical bottom of each clutch below the same shaft. For example, when mounted in a vehicle located on the ground, low speed clutch 230 is oriented such that the vertical top of the clutch is above shaft 227 and the vertical bottom of the clutch is below shaft 227 relative to the vertical axis / gravity.

[0042] Figure 2A The multi-range clutch is shown in an intermediate disconnect position. Each of the clutch plates 234, 236, 205, and 203 is depicted as disengaged. In some examples, the intermediate disconnect position may not be used for actual use of the transmission system 200, but in other examples, the intermediate disconnect position may represent an idle or neutral position of the transmission.

[0043] In an alternative example, the transmission system 200 includes another electric traction motor, such as a second electric motor 282. In this example, the electric motor 202 can be a first electric motor. The second electric motor 282 can be coupled to the transmission system 200 via a shaft 284. Similar to the shaft 224, the shaft 284 can be a rotor shaft. Bearings 290 located at either end of the shaft 284 can support and facilitate the rotation of the shaft 224. The shaft 284 can be coupled to a gear 286. Similar to the gear 212, the gear 286 can be rotatably coupled to the gear 213. In this example where the second electric motor 282 is included in the transmission system 200, the first input reduction gear set 204 can include a gear 286, a gear 213, and a gear 212 coupled to the input shaft 225. The second electric motor 282 can be vertically positioned above the electric motor 202. The shaft 284 can be vertically positioned above the shaft 224.

[0044] The option of two motors may allow for higher power to be provided without having to increase the size of a single motor. It may also be easier to package two relatively small motors than a single relatively large motor. In addition, the option for a second motor may allow the second motor to act as a backup motor if the first motor overheats. Furthermore, having two different input ratios may provide high speed / low torque and low speed / high torque options.

[0045] Figure 2B The shifting strategies depicted in show four available configurations of a multi-ratio gearbox, as described in detail above. In these configurations, there can be two clutches engaged for each ratio, wherein the multi-range clutch 207 is in one of two available positions, and either the low-speed clutch or the high-speed clutch is engaged. Figure 2A The neutral position of the multi-range clutch 207 shown in the figure may not be used for any of these ratios. In addition, during operation of the transmission system 200, at least one of the low-speed clutch 230 or the high-speed clutch 232 may be engaged. Therefore, the transmission system 200 is capable of achieving four speeds in the reverse direction and the forward direction via three clutches—the multi-range clutch 207, the low-speed clutch 230, and the high-speed clutch 232.

[0046] In some examples, the transmission system 200 may embody an overlapping shifting method. For example, when upshifting from a first configuration of the system to a second configuration of the system, the pressure on the clutch plates 205 and 234 engaged in the first position 220 may decrease as the pressure on the clutch plates 203 and 236 engaged in the second position 222 increases. Figure 5 Other examples of gear shifting scenarios are described. The overlapping gear shifting method described herein can reduce the power interruption caused by gear shifting and increase smoothness.

[0047] The layout of the second section (multi-range clutch 207) of the multi-ratio gearbox described herein is such that there is a reduced gear dispersion between the first position and the second position. This reduced gear dispersion can result in more equal and smaller gear sizes than when using a larger gear dispersion. In turn, this can produce lower gear / shaft speeds, which can avoid excessive shaft speeds and clutch speeds. Too high shaft speeds and clutch speeds may become a problem of required bearing size. As described above, due to high power loads, the relatively large bearings required in one embodiment of the present disclosure do not allow high speeds. The output speed reduced via the input reduction gear set allows the use of relatively large bearings. When the low-speed clutch 230 is engaged, a further reduction in output speed can be achieved, which can also reduce the load level circulating through the gearbox. The lower load on the components can allow smaller-sized components to be used for similar high power levels. Smaller-sized components are obviously advantageous because they require a relatively small envelope for the transmission.

[0048] Now go to Figure 3A -D, providing a power path for each of the four gear / clutch ratios of the transmission system. Figure 3A -D The transmission system shown can be Figure 2A A transmission system 200 is provided. Figure 3A The power paths for a first configuration of the system are depicted. Figure 3B The power paths for the second configuration of the system are depicted. Figure 3C The power paths for the third configuration of the system are depicted. Figure 3D Depicts the power path for the fourth configuration of the system. For consistency, the components herein are similar to Figure 2A In each of the four configurations of the system, power is transferred from the electric motor 202 (and the second electric motor 282 in embodiments that include a second electric motor) through the first input reduction gear set 204 to the input shaft 225. Power is transferred from the input shaft 225 to the gear 214 and then to the gear 215. The electric motor 202, the first input reduction gear set 204, the input shaft 225 and the gear 214 are arranged in a manner similar to that of the first input reduction gear set 204. Figure 3A -D is not explicitly shown. In addition, after passing through the engaged clutch and the associated gears and shafts, power is transferred from gear 219 to gear 229. From gear 229, power enters shaft 228 and reaches output interface 260, which can transfer rotational power downstream. Gear 229, output shaft 238 and output interface 260 are in Figure 3A -D is not explicitly shown.

[0049] During conditions of the first configuration of the system, where the multi-range clutch 207 is in the first position 220 and the low speed clutch 230 is engaged, gear 216 can be coupled to gear 218 via gear 209 when clutch plates 205 and 234 are engaged. Low speed clutch 230 is fixedly coupled to gear 218 and can also be coupled to gear 219 via gear 210 when clutch plates 240 and 242 are engaged. Power enters shaft 226 from gear 215 and is then transferred to gear 216. Power enters gear 209 from gear 216 through the engaged clutch plates 205 and 234. The power path travels from gear 209 into gear 218 and into the low speed clutch 230, through the engaged clutch plates 240 and 242 and into gear 210. The power path travels from gear 210 into gear 219 and then downstream toward output interface 260 as described above.

[0050] During conditions of the second configuration of the system, where the multi-range clutch 207 is in the second position 222 and the low-speed clutch 230 is engaged, when the clutch plates 203 and the clutch plates 236 are engaged, the gear 216 can be coupled to the gear 217 via the gear 208. The gear 217 is coupled to the shaft 227, which is further coupled to the gear 218. The low-speed clutch 230 is fixedly coupled to the gear 218, and can also be coupled to the gear 219 via the gear 210 when the clutch plates 240 and the clutch plates 242 are engaged. The gear 210 is further coupled to the gear 219. The power path travels from the gear 215 into the shaft 226, and then into the gear 216. The power from the gear 216 passes through the engaged clutch plates 203 and the clutch plates 236 into the gear 208. The power path travels from the gear 208 into the gear 217, the shaft 227, and the gear 218. Power travels from gear 218 into low speed clutch 230, through engaged clutch plates 240 and 242 into gear 210. The power path travels from gear 210 into gear 219 and then downstream towards output interface 260 as described above.

[0051] During conditions of the third configuration of the system, where the multi-range clutch 207 is in the first position 220 and the high speed clutch 232 is engaged, gear 216 can be coupled to gear 218 via gear 209 when clutch plates 205 and 234 are engaged. High speed clutch 232 is fixedly coupled to gear 219 and can also be coupled to gear 218 via gear 211 when clutch plates 244 and 246 are engaged. Power enters shaft 226 from gear 215 and is then transferred to gear 216. Power enters gear 209 from gear 216 through the engaged clutch plates 205 and 234. The power path travels from gear 209 into gear 218 and into high speed clutch 232 via gear 211. Power enters gear 219 from gear 211 through the engaged clutch plates 244 and 246.

[0052] During conditions of the fourth configuration of the system, where the multi-range clutch 207 is in the second position 222 and the high-speed clutch 232 is engaged, when the clutch plates 203 and 236 are engaged, the gear 216 can be coupled to the gear 217 via the gear 208. The gear 217 is coupled to the shaft 227, which is further coupled to the gear 218. The high-speed clutch 232 is fixedly coupled to the gear 219, and can also be coupled to the gear 218 via the gear 211 when the clutch plates 244 and 246 are engaged. The power path travels from the gear 215 into the shaft 226, and then into the gear 216. The power from the gear 216 passes through the engaged clutch plates 203 and 236 into the gear 208. The power path travels from the gear 208 into the gear 217, the shaft 227, and the gear 218. The power path travels from the gear 218 into the high-speed clutch 232 via the gear 211. Power passes through engaged clutch plate 244 and clutch plate 246 into gear 219 .

[0053] As previously described, the low speed clutch 230 and the high speed clutch 232 double the number of total speeds of the transmission system 200. In one embodiment, there may be two initial speeds from the multi-range clutch (e.g., the first position 220 and the second position 222). The sequence of clutches and gears described above allows for a reduced dispersion of clutch ranges while doubling the number of available speeds. Advantageously, this four-speed layout is relatively small and can be used in specific applications requiring a smaller transmission envelope. Additionally, when oriented in a vehicle, the architecture can enable the top of the motor(s) driving the transmission to be lower than the top of the transmission housing to better fit the desired vehicle envelope.

[0054] As previously described, there may be a controller 112 having stored therein instructions for operating the multi-ratio transmission, wherein the motor rotates in a first forward direction at each of four different gear ratios, the four different gear ratios including: (1) the multi-range clutch is in a first position (e.g., first position 220), the low-speed clutch 230 is engaged, and the high-speed clutch 232 is disengaged, (2) the multi-range clutch is in a second position (e.g., second position 222), the low-speed clutch 230 is engaged, and the high-speed clutch 232 is disengaged, (3) the multi-range clutch is in a first position (e.g., first position 220), the low-speed clutch 230 is disengaged, and the high-speed clutch 232 is engaged, and (4) the multi-range clutch is in a second position (e.g., second position 222), the low-speed clutch 230 is disengaged, and the high-speed clutch 232 is engaged. The controller 112 may also have instructions for further operating the multi-ratio transmission, wherein the motor rotates in a second reverse direction at each of the four gear ratios, wherein the multi-ratio transmission does not reversely rotate via any of the multi-range clutch, the low-speed clutch, and the high-speed clutch.

[0055] In one example, the transmission described herein may have exactly four gear ratios in each of the forward and reverse directions.

[0056] Now go to Figure 4 , an example of a transmission housing 400 is shown. Figure 4 The drawings are drawn to scale, but other relative sizes may be used if desired. Figure 2A The transmission system 200 can be accommodated in the transmission housing 400. The transmission housing 400 includes an upper section 420 and a lower section 422. The upper section 420 of the transmission housing 400 can accommodate the reference Figure 2A Each of the first section, the second section, and the third section of the multi-ratio gearbox is depicted. The lower section 422 of the transmission housing 400 may house the output shaft 238 and the gear 229, which are spaced apart from the first section, the second section, and the third section.

[0057] In some embodiments, electric motor 202 may be housed within a motor housing (not shown) that is coupled to transmission housing 400. Figure 4The transmission system 200, the electric motor 202, and the control system 114 are not visible in the view of the transmission housing 400 shown. The offset box 402 can allow a drive motor (e.g., the electric motor 202) to be input into the transmission system 200. The relative positioning of the electric motor 202 and the transmission system 200 can be such that the electric motor 202 and its motor housing (not shown) are mounted to the transmission system 200 at a position not exceeding the highest point of the transmission system 200 and the transmission housing 400. Placing the electric motor 202 below the highest point of the transmission can allow one or more input reduction gear sets. As previously described, these input reduction gear sets can reduce the torque load of the entire multi-ratio gearbox and allow for larger bearing sizes. Placing the electric motor 202 below the highest point of the transmission system 200 can also reduce the overall required size of the transmission housing. The transmission housing 400 can also contain a gear set to match the maximum electric motor 202 speed to the maximum transmission system 200 input speed.

[0058] The gear 229 and the output shaft 238 can be configured to fit within the dimensions of the lower section 422 of the transmission housing 400. For example, the diameter of the gear 229 can be configured to fit within the height 426 of the lower section 422. The width of the output shaft 238 and the distance between the output interfaces 260 can be configured to fit within the width 424 of the lower section 422. The width 424 can be shorter than the width of the upper section 420, and can be shorter than the width of the shaft 228 because the shaft 228 is directly coupled to the high speed clutch 232, while the output shaft 238 is not directly coupled to the clutch. The reduced width of the output shaft 238 can allow the transmission system 200 to be installed in a vehicle platform that requires a short distance between output interfaces.

[0059] Additionally, another input may provide the option of coupling the second electric motor 282 to the transmission housing via the bias box 403. Horizontal axis 410, horizontal axis 411, and horizontal axis 412 are also provided. Figure 4 Depicted in. Figure 4 Horizontal axis 410, horizontal axis 411, and horizontal axis 412 are also depicted. Horizontal axis 410 can correspond to the horizontal axis of shaft 284 to which second electric motor 282 is coupled. Horizontal axis 412 can correspond to the horizontal axis of the fifth shaft (e.g., output shaft 238) of the multi-ratio gearbox. Horizontal axis 410, horizontal axis 411, and horizontal axis 412 can all be parallel to each other.

[0060] In addition, the charge pump 404 can be directly coupled to the vertical top of the transmission housing 400 so that the charge pump 404 and the transmission housing 400 are in face-to-face contact. In some embodiments, the charge pump 404 can be driven by an electric motor 406. In one embodiment, the electric motor 406 can be an electric pump motor that is separate from the electric traction motor (e.g., the motor 202) that drives the transmission components. The charge pump 404 can be removable. As an option, the charge pump 404 can be separated from the transmission system 200 so that the charge pump 404 and the electric motor 406 that drives the charge pump 404 are in a remote location and connected to the transmission housing 400 via input and output hoses (not shown). The option of being able to keep the charge pump 404 directly on the transmission housing 400 further reduces the size of the system, which can reduce the size required for the envelope of the transmission and / or can allow for more precise control of the transmission hydraulic pressure, which in turn can increase shift control.

[0061] Reference now Figure 5 , a use case scenario of a transmission system is shown in a timing diagram 500. The transmission system may be Figure 2A The transmission system 200 of FIG. 5 is shown in FIG. 5 . In each figure, time is indicated on the abscissa and increases from left to right. The ordinate of curve 502 indicates the position of the multi-range clutch (“first position” or “second position”). The first position of the multi-range clutch may be the first position 220 of the multi-range clutch 207. The second position of the multi-range clutch may be the second position 222. The ordinate of curve 504 indicates the operating state of the clutch plate of the first position of the multi-range clutch (“engaged” or “disengaged”). The ordinate of curve 506 indicates the operating state of the clutch plate of the second position of the multi-range clutch (“engaged” or “disengaged”). The ordinate of curve 508 indicates the operating state of the low-speed clutch (“engaged” or “disengaged”). The ordinate of curve 510 indicates the operating state of the high-speed clutch (“engaged” or “disengaged”). “Engaged” indicates that the corresponding clutch allows the transmission of rotational energy through it, and “disengaged” indicates that the transmission of rotational energy through the clutch is suppressed.

[0062] At t0, the multi-range clutch is in the first position, so the clutch plate of the first position is engaged and the clutch plate of the second position is disengaged. The low-speed clutch is engaged and the high-speed clutch is disengaged. T0 may represent the operating state of the clutch in the first configuration of the transmission system. Between t0 and t1, the clutch plate of the first position transitions from engaged to disengaged at the same time as the clutch plate of the second position transitions from disengaged to engaged. Thus, the multi-range clutch position transitions from the first position to the second position. T1 may represent the operating state of the clutch in the second configuration of the transmission system.

[0063] Between t1 and t2, the clutch plate in the first position transitions from disengaged to engaged at the same time as the clutch plate in the second position transitions from engaged to disengaged. Thus, the multi-range clutch position transitions from the second position to the first position. The low-speed clutch also transitions from engaged to disengaged at the same time as the high-speed clutch transitions from disengaged to engaged. T2 may represent the operating state of the clutch in the third configuration of the transmission.

[0064] Between t2 and t3, the clutch plate in the first position transitions from engagement to disengagement while the clutch plate in the second position transitions from disengagement to engagement. Thus, the multi-range clutch position transitions from the first position to the second position. The low speed clutch remains disengaged and the high speed clutch remains engaged. T3 may represent an operating state of the clutch in a fourth configuration of the transmission system.

[0065] Between t3 and t4, the clutch plate in the first position transitions from disengaged to engaged while the clutch plate in the second position transitions from engaged to disengaged. Thus, the multi-range clutch position transitions from the second position to the first position. The low speed clutch remains disengaged and the high speed clutch remains engaged. T4 may represent an operating state of the clutch in a third configuration of the transmission.

[0066] Between t4 and t5, the clutch plate in the first position transitions from engaged to disengaged at the same time as the clutch plate in the second position transitions from disengaged to engaged. Thus, the multi-range clutch position transitions from the first position to the second position. The high speed clutch also transitions from engaged to disengaged at the same time as the low speed clutch transitions from disengaged to engaged. T5 may represent an operating state of the clutch in the second configuration of the transmission system.

[0067] Between t5 and t6, the clutch plate in the first position transitions from disengaged to engaged while the clutch plate in the second position transitions from engaged to disengaged. Thus, the multi-range clutch position transitions from the second position to the first position. The low speed clutch remains engaged and the high speed clutch remains disengaged. T6 may represent an operating state of the clutch in the first configuration of the transmission.

[0068] The times between t0 and t1, between t1 and t2, and between t2 and t3 may represent upshift transients between gear / clutch ratios. Conversely, the times between t3 and t4, between t4 and t5, and between t5 and t6 may represent downshift transients between gear / clutch ratios. Other or additional upshift and downshift transients not depicted in timing diagram 500 are also possible. For example, a downshift variation from the fourth configuration to the second configuration may be achieved by transitioning the high speed clutch from engagement to disengagement while transitioning the low speed clutch from disengagement to engagement.

[0069] The transitions between the operating states of the clutch described herein can be controlled by a control system (e.g. Figure 1 The control system 114 of the embodiment of the present invention is controlled by actuators and sensors of the control system 114 of the embodiment of the present invention. For any of curves 504, curves 506, curves 508 and / or curves 510, the transition from the engaged state to the disengaged state can include a decrease in pressure on the clutch plates. The transition from the disengaged state to the engaged state can include an increase in pressure on the clutch plates. When transitioning between the first position and the second position of the multi-range clutch, or vice versa, the pressure on one set of clutch plates decreases while the pressure on another set of clutch plates increases. Similarly, the transition between the high-speed clutch and the low-speed clutch can include increasing the pressure in one clutch while reducing the pressure in the other clutch. Overlap shifting methods like this can increase the smoothness of shifting between ratios and reduce interruptions during shifting.

[0070] The present disclosure also provides support for a system for a multi-ratio gearbox, the system comprising: a first shaft coupled to one or more input reduction gear sets, a second shaft coupled to a multi-range clutch, the multi-range clutch comprising a first position and a second position, a third shaft coupled to a low-speed clutch, a fourth shaft coupled to a high-speed clutch, and a fifth shaft coupled to the fourth shaft via a plurality of gears. In a first example of the system, the first shaft is an input shaft. In a second example of the system, optionally including the first example, the fifth shaft is an output shaft. In a third example of the system, optionally including one or both of the first example and the second example, the second shaft, the third shaft, and the fourth shaft are secondary shafts. In a fourth example of the system, optionally including one or more or each of the first to third examples, the first shaft, the second shaft, the third shaft, the fourth shaft, and the fifth shaft are parallel to each other. In a fifth example of the system, optionally including one or more or each of the first to fourth examples, the fifth shaft is vertically positioned below the first shaft, the second shaft, the third shaft, and the fourth shaft relative to gravity. In a sixth example of the system, optionally including one or more or each of the first to fifth examples, the multi-range clutch includes a first position coupling the second shaft to the third shaft via a low gear and a second position coupling the second shaft to the third shaft via a high gear. In a seventh example of the system, optionally including one or more or each of the first to sixth examples, the fifth shaft is spaced apart from the fourth shaft via a gear coupling the fifth shaft to the fourth shaft. In an eighth example of the system, optionally including one or more or each of the first to seventh examples, the fifth shaft is coupled to two output interfaces, and the distance between the two output interfaces is short.

[0071] The present disclosure also provides support for a multi-speed transmission, the multi-speed transmission comprising: a first electric motor coupled to an input side of a first shaft of a plurality of shafts, a multi-range clutch coupled to a second shaft of the plurality of shafts, the multi-range clutch comprising a first position and a second position, a low speed clutch coupled to a third shaft of the plurality of shafts, a low speed clutch coupled to a fourth shaft of the plurality of shafts, and a controller having instructions stored therein to operate the multi-speed transmission, wherein the first electric motor rotates in a first forward direction in each of four gear ratios, the four gear ratios comprising: (1) the multi-range clutch is in a first position, the low speed clutch is engaged, and the high speed clutch is disengaged, (2) the multi-range clutch is in a second position, the low speed clutch is engaged, and the high speed clutch is disengaged, (3) the multi-range clutch is in a first position, the low speed clutch is disengaged, and the high speed clutch is engaged, and (4) the multi-range clutch is in a second position, the low speed clutch is disengaged, and the high speed clutch is engaged, and the instructions further operate the multi-speed transmission, wherein the first electric motor rotates in a second reverse direction in each of the four gear ratios, wherein the multi-speed transmission does not reversely rotate via any of the multi-range clutch, the low speed clutch, and the high speed clutch. In a first example of the system, the system further includes: a charge pump directly coupled to the housing of the multi-speed gearbox. In a second example of the system, optionally including the first example, the system further includes: a pump motor coupled to the charge pump, the drive motor being directly coupled to the housing. In a third example of the system, optionally including one or both of the first and second examples, the system further includes: a first electric motor and a second electric motor coupled to the input side of the first shaft. In a fourth example of the system, optionally including one or more or each of the first to third examples, the first electric motor and the second electric motor are coupled to the input side of the first shaft via different gear ratios.

[0072] The utility model also provides support for a system, which includes: an intermediate shaft power shift transmission with an input portion; a transmission housed in a transmission housing; an electric traction motor coupled to the input portion; an electric traction motor housed in a motor housing, wherein the vertical top of the motor housing is below the top of the transmission housing; and a distance between the output interfaces of the transmission, the output interface being configured to fit within the lower section of the transmission housing. In a first example of the system, the intermediate shaft power shift transmission is a four-speed transmission, including a first shaft coupled to one or more input reduction gear sets, a second shaft coupled to a multi-range clutch, a third shaft coupled to a low-speed clutch, a fourth shaft coupled to a high-speed clutch, and a fifth shaft coupled to the output interface and the fourth shaft. In a second example of the system, optionally including the first example, the fifth shaft is an output shaft. In a third example of the system, optionally including one or both of the first and second examples, a gear in a plurality of gears couples the fifth shaft to the fourth shaft, and the gear is configured to fit within the height of the lower section of the transmission. In a fourth example of the system, optionally including one or more or each of the first to third examples, the system further includes: another electric traction motor coupled to another input of the intermediate shaft powershift transmission. In a fifth example of the system, optionally including one or more or each of the first to fourth examples, the first shaft, the second shaft, the third shaft, the fourth shaft, and the fifth shaft are all arranged parallel to each other, and wherein, when arranged in a vehicle, the first shaft is located vertically above the second shaft, the second shaft is located vertically above the third shaft, the third shaft is located vertically above the fourth shaft, and the fourth shaft is located vertically above the fifth shaft.

[0073] Although various embodiments have been described above, it should be understood that they are presented as examples rather than limitations. It will be apparent to those skilled in the relevant art that the disclosed subject matter may be implemented in other specific forms without departing from the spirit of the subject matter. Therefore, the above embodiments are considered to be illustrative rather than restrictive in all respects.

[0074] It should be noted that the example control and estimation routines included herein can be used with various powertrain and / or vehicle system configurations. The control methods and routines disclosed herein can be stored as executable instructions in non-transitory memory and can be executed by a control system including a controller combined with various sensors, actuators and other vehicle hardware. In addition, the parts of the method can be physical actions taken in the real world to change the state of the device. The specific routines described herein can represent one or more of any number of processing strategies such as event-driven, interrupt-driven, multi-tasking, multi-threading, etc. In this way, the various actions, operations and / or functions shown can be performed in the order shown, in parallel, or omitted in some cases. Similarly, the processing order of the features and advantages of the exemplary examples described herein is not necessary, but is provided for ease of illustration and description. Depending on the specific strategy used, one or more of the actions, operations and / or functions shown can be repeatedly performed. In addition, the described actions, operations and / or functions can graphically represent the code in the non-transitory memory of the computer-readable storage medium to be programmed into the vehicle control system, wherein the described actions are performed by executing instructions in a system including various hardware components and combined with an electronic controller. If desired, one or more of the method steps described herein may be omitted.

[0075] It will be appreciated that the configurations and routines disclosed herein are exemplary in nature, and these specific examples should not be considered limiting, as a variety of variations are possible. For example, the above techniques can be applied to power systems that include different types of propulsion sources, including different types of motors and transmissions. The subject matter of the present disclosure includes all novel and non-obvious combinations and sub-combinations of the various systems and configurations and other features, functions, and / or properties disclosed herein.

[0076] The appended claims particularly point out certain combinations and subcombinations believed to be novel and non-obvious. These claims may refer to "an" element or a "first" element or the equivalent thereof. Such claims should be understood to include combinations of one or more such elements, neither requiring nor excluding two or more such elements. Other combinations and subcombinations of the disclosed features, functions, elements, and / or characteristics may be claimed in this or a related application by amendment of the present claims or by presentation of new claims. Such claims, whether broader, narrower, equal, or different in scope to the original claims, are deemed to be included in the subject matter of the present disclosure.

Claims

1. A system for a multi-ratio gearbox, characterized in that: include: a first shaft coupled to one or more input reduction gear sets; a second shaft coupled to a multi-range clutch including a first position and a second position; a third shaft coupled to a low-speed clutch; a fourth shaft coupled to the high-speed clutch; as well as A fifth shaft is coupled to the fourth shaft via a gear of a plurality of gears.

2. The system according to claim 1, characterized in that The first shaft is an input shaft.

3. The system according to claim 1, characterized in that The fifth shaft is an output shaft.

4. The system according to claim 1, characterized in that The second shaft, the third shaft and the fourth shaft are secondary shafts.

5. The system according to claim 1, characterized in that The first axis, the second axis, the third axis, the fourth axis, and the fifth axis are parallel to each other.

6. The system according to claim 1, characterized in that The fifth axis is positioned vertically below the first axis, the second axis, the third axis, and the fourth axis relative to gravity.

7. The system according to claim 1, characterized in that The multi-range clutch includes a first position coupling the second shaft to the third shaft via a low gear and a second position coupling the second shaft to the third shaft via a high gear.

8. The system according to claim 1, characterized in that The fifth shaft is spaced apart from the fourth shaft via a gear coupling the fifth shaft to the fourth shaft.

9. The system according to claim 1, characterized in that The fifth shaft is coupled to two output interfaces, and a distance between the two output interfaces is short.

10. The system according to claim 1, characterized in that Also included is a controller having stored therein instructions to operate a multi-ratio transmission wherein the first electric motor rotates in a first forward direction at each of four gear ratios, the four gear ratios comprising: (1) the multi-range clutch is in a first position, the low-speed clutch is engaged, and the high-speed clutch is disengaged, (2) the multi-range clutch is in a second position, the low-speed clutch is engaged, and the high-speed clutch is disengaged, (3) the multi-range clutch is in the first position, the low-speed clutch is disengaged, and the high-speed clutch is engaged, and (4) the multi-range clutch is in the second position, the low-speed clutch is disengaged, and the high-speed clutch is engaged; and the instructions further operate the multi-ratio transmission wherein the first electric motor rotates in a second reverse direction at each of the four gear ratios, wherein the multi-ratio transmission does not rotate in the reverse direction via any of the multi-range clutch, the low-speed clutch, and the high-speed clutch.

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