DESCRIPTION

Technical Field

[001] This disclosure relates generally to a gear system, and more particularly to a gear system for increasing revolutions per minute (RPM) of an output with respect to an input shaft.

BACKGROUND

[002] Gears are long known to be used for the transmission of motion.

A gear train or a gear system is a combination of gears which is used to transmit motion from one shaft to another. Gear train is mainly used to connect shafts separated by large distance and to get desired direction of rotation, and/or to obtain speed gaining or reduction. A gear train having a relative motion of axes is called a planetary or an epicyclic gear train system. In an epicyclic gear train the gears revolve about axes that are not fixed rather rotating.

[003] The planetary or epicyclic gear train system may be used to obtain high speed reductions in compact space. Further, in the planetary gear train, load is shared among multiple planetary gears, so there is an assurance of uniform load distribution among the planets. Therefore, it can be used for higher power transmission. Due to the use of planet gears in planetary gear system, torque capability is also greatly increased. Further, with the use of more planet gears in the system, the load ability and torque density can be increased greatly. Also, the planetary gear system creates more contact surfaces and a larger contact area between the gears, because of which, the load is more evenly distributed and therefore the gears are more resistant to damage. Planetary gear system also creates greater stability due to the even distribution of mass.

[004] However., an improved gear system is desired that is capable of increasing speed by high ratios and effective motion transfer, has simple yet robust construction, and is easy to maintain and use. SUMMARY

[005] In one embodiment, a gear system is disclosed. The system includes a central hub, a ring gear, a sun gear, a plurality of planet gears, and a plurality of carrier arms. The sun gear and ring gear may be coaxial with the central hub. The sun gear includes a plurality of gear teeth is defined on an outer side of the sun gear. The ring gear may include a plurality of gear teeth defined on an inner side of the ring gear. The sun gear may be rotatable around a central axis passing through the centre of the sun gear, the central hub, and the ring gear. The ring gear may remain static. Each of the plurality of carrier arms may be attached to central hub via a first end of the associated carrier arm and to the ring gear via a second end of the associated carrier arm. The carrier may be configured to hold the plurality of planet gears. Each carrier arm of the plurality of carrier arms may include a plurality of slots, for mounting a plurality of axles. Each of the planet gear may be mounted on an associated carrier arm via associated axle. The plurality of planet gears may have centre axes that are parallel with the central hub, sun gear and ring gear.

[006] Each set of the plurality of planet gears may include three sets of planet gears. Further, each set of plurality of planet gears may include nine to twenty-four planet gears. The plurality of sets of planet gears may include 3 sets of planet gears. Each set of the planet gears may include three gears, each of same radius. The first planet gear among the set of the planet gears having first radius may be configured to mesh with the sun gear and the second planet gear. Similarly, the second planet gear among the set of the planet gears having second radius may be configured to mesh with the first planet gear and the third planet gear. Likewise, the third planet gear from the set of the planet gears having a third radius may be configured to mesh with the second gear and the ring gear. The first radius may be smaller than the second radius, and the second radius is smaller than the third radius. The set of planet gears with the smallest radius may be in mesh with the sun gear and the set of planet gears with the largest radius may in be mesh with the ring gear. The radius of the first planet gear, second planet gear and third planet gear may be unique relative to each other. [007] The sun gear may be configured to act as either driver gear or driven gear based on the load/torque requirement. When our requirement is to increase the revolutions per minute at output then the power input may rotate the planet carrier which in turn rotates all the planet gears and the last set of planet gear that may be in mesh with the sun gear will rotate the sun gear. Through this process, the revolutions per minute of sun gear will increase with respect to the revolutions per minute of the planet gears. And to decrease the revolutions per minute at the output according to the load requirement the above process will be reversed with sun gear moving first, acting as a driver and thereby rotating planet gears with decreased revolutions per minute in order to maintain gear ratio.

BRIEF DESCRIPTION OF THE DRAWINGS

[008] The accompanying drawings, which are incorporated in and constitute a part of this disclosure, illustrate exemplary embodiments and, together with the description, serve to explain the disclosed principles.

[009] FIG. 1 illustrates a perspective view of a gear system, in accordance with an embodiment of the present disclosure.

[010] FIG. 2 illustrates a front view of the gear system of FIG. 1, in accordance with an embodiment of the present disclosure.

[Oil] FIG. 3 illustrates a front view of a carrier of the gear system of

FIG. 1, in accordance with an embodiment of the present disclosure.

DETAILED DESCRIPTION

[012] Exemplary embodiments are described with reference to the accompanying drawings. Wherever convenient, the same reference numbers are used throughout the drawings to refer to the same or like parts. While examples and features of disclosed principles are described herein, modifications, adaptations, and other implementations are possible without departing from the spirit and scope of the disclosed embodiments. It is intended that the following detailed description be considered as exemplary only, with the true scope and spirit being indicated by the following claims. Additional illustrative embodiments are listed below.

[013] Referring to FIG. 1, a perspective view of a gear system 100 is illustrated, in accordance with an embodiment of the present disclosure. An input shaft may be coupled to the gear system 100. For example, the input shaft may be coupled to an animal-operated mill for electricity generation. Since the speed (RPM) of the mill run by animals is inadequately low for running an electricity generator, there is need for increasing the speed. To this end, the gear system 100 is provided.

[014] The gear system 100 may include a carrier 102. For example, the input shaft may be coupled to the carrier 102. The carrier 102 may have a provision to mount a plurality of the planet gears 114 on it. To this end, the carrier may include a plurality of carrier arms 110. The planet gears 114 may be mounted on each of the plurality of carrier arms 110, via a plurality of axles 118 through a plurality of the slots 116 provided on the plurality of the carrier arms 110.

[015] The carrier 102 may include a central hub 104, a ring gear 106 coaxial with the central hub 104. The carrier 102 may further include a plurality of carrier arms 110-1, 110-2, and 110-3. Each of the plurality of carrier arms 110 may include a first end 110A and a second end HOB. For example, the carrier arm 110-1 may include a first end 110-1A and a second end 110-1B. Similarly, the carrier arm 110-2 may include a first end 110-2 A and a second end 110-2B. Likewise the carrier arm 110-3 may include a first end 110-3A and a second end 110-2C.

[016] The central hub 104 may include a coupler 104A. The coupler

104 A may be used for coupling the input shaft to the carrier 102. For example, the coupler 104 A may be a splined portion including a plurality of splines. This splined portion may be coupled with a similar splined portion on the input shaft to which the carrier may be coupled to receive motion.

[017] The ring gear 106 may be coaxial with the central hub 104. The ring gear 106 may include a plurality of gear teeth 108 defined on an inner side of the ring gear 106. The ring gear 106 may be coaxial with the central hub 104. The ring gear 106 may include involute spur teeth. In an example embodiment, for the ring gear 106, number of teeth may be 439, module may be 6, pitch may be 18.9 mm, addendum may be 6 mm, dedendum may be 7.5 mm, working depth may be 12 mm, clearance may be 1.5 mm, whole depth may be 13.5 mm, and diameter may be 2646 mm. Further, the ring gear 106 may be configured to act as a fixed gear.

[018] Each of the plurality of carrier arms 110 may be attached to central hub 104 via the first end 110A of the associated carrier arm 110 and to the ring gear 106 via the second end HOB of the associated carrier arm 110. This is further explained in conjunction with FIG. 3.

[019] Referring now to the FIG. 3, a front view of the carrier 102 is illustrated. The carrier 102 may include the carrier arms 110-1, 110-2, and 110-3. For example, the carrier arm 110-1 may be attached to central hub 104 via the first end 110-1A and to the ring gear 106 via the second end 110-1B. Similarly, the carrier arm 110-2 may be attached to central hub 104 via the first end 110-2 A and to the ring gear 106 via the second end 110-2B. Further, the carrier arm 110-3 may be attached to central hub 104 via the first end 110-3A and to the ring gear 106 via the second end 110-3B.

[020] Referring now to FIG. 2, a front view of the gear system 100 is illustrated in accordance with an embodiment of the present disclosure, with reference to FIGS. 1-2, the gear system 100 may include a sun gear 112. In an example embodiment, for the sun gear 112, number of teeth may be 15, module may be 6, pitch may be 21.35 mm, addendum may be 6 mm, dedendum may be 7.5 mm, working depth may be 12 mm, clearance may be 1.5 mm, whole depth may be 13.5 mm, and diameter may be 102 mm. The sun gear 112 may be configured to act as a driven gear as it is coupled to the output shaft. The sun gear 112 may be rotatable around a central axis AA passing through the centre of the sun gear 112, the central hub 102, and the ring gear 106.

[021] The gear system 100 may further include a plurality of planet gears 114 (collectively referred to as plurality of planet gears 114). These plurality of planet gears 114 may be configured to rotate around the sun gear 112. Each planet gear may be assembled on the associated carrier arm via axles. These planet gears 114 may be having centre axes that are parallel with the axes of sun gear 112 and ring gear 106. Planet gears may be free to rotate with respect to their mounting carrier arms on the carrier, respectively. Each gear here may be the involute spur gear and is made up of Iron Grade 8 & 9. Each gear has pitch circle diameter of 19.15 mm; 19.46 mm and 20.09 mm respectively.

[022] The plurality of planet gears 114 may include a plurality of sets of planet gears, for example, a first set 114-1, a second set 114-2, and a third set 114-3. Each set of the plurality of sets of planet gears may include a first planet gear (114A) having a first radius, a second planet gear (114B) having a second radius, and a third planet gear (114C) having a third radius.

[023] For example, the first set of planet gears 110-1 may include a first planet gear 114-1A, a second planet gear 114-1B, and a third planet gear 114-1C. Similarly, the second set of planet gears 110-2 may include a first planet gear 114-2A, a second planet gear 114-2B, and a third planet gear 114-2C. Further, the third set of planet gears 110-3 may include a first planet gear 114-3 A, a second planet gear 114-3B, and a third planet gear 114-3C.

[024] Further, the first planet gear 114-1 A, the first planet gear 114-

2A, and the first planet gear 114-3A my have a first radius, i.e., radius of the first planet gear 114-1A, the first planet gear 114-2A, and the first planet gear 114-3A is same and equal to the first radius. In one example embodiment, for the first planet gear 114-1 A, the first planet gear 114-2A, and the first planet gear 114-3A, number of teeth may be 30, module may be 6, pitch may be 20.09 mm, addendum may be 6 mm, dedendum may be 7.5 mm, working depth may be 12 mm, clearance may be 1.5 mm, whole depth may be 13.5 mm, diameter may be 192 mm, and radius may be 96 mm.

[025] The second planet gear 114-1B, the second planet gear 114-2B, and the second planet gear 114-3B may have a second radius. In other words, radius of the second planet gear 114-1B, the second planet gear 114-2B, and the second planet gear 114-3B is same and equal to the second radius. In one example embodiment, for each of the second planet gear 114- IB, the second planet gear 114-2B, and the second planet gear 114-3B, number of teeth may be 60, module may be 6, pitch may be 19.46 mm, addendum may be 6 mm, dedendum may be 7.5 mm, working depth may be 12 mm, clearance may be 1.5 mm, whole depth may be 13.5 mm, diameter may be 372 mm, and radius may be 186 mm.

[026] The third planet gear 114-1C, the third planet gear 114-2C, and the third planet gear 114-3C may have a third radius. In other words, the radius of the third planet gear 114-1C, the third planet gear 114-2C, and the third planet gear 114-3C is same and equal to the third radius. In one example embodiment, for each of the third planet gear 114-1C, the third planet gear 114-2C, and the third planet gear 114-3C, number of teeth may be 120, module may be 6, pitch may be 19.15 mm, addendum may be 6 mm, dedendum may be 7.5 mm, working depth may be 12 mm, clearance may be 1.5 mm, whole depth may be 13.5 mm, diameter may be 732 mm, and radius may be 366 mm.

[027] The first planet gear 114-1 may be configured to mesh with the sun gear 112 and the second planet gear 114-2. Further, the second planet gear 114-2 may be configured to mesh with the first planet gear 114-1 and the third planet gear 114-3. Further, the third planet gear 114-3 may be configured to mesh with the second gear 114-2 and the ring gear 106.

[028] In particular, the first planet gear 114-1 A may be configured to mesh with the sun gear 112 and the second planet gear 114- IB. Further, the second planet gear 114- IB may be configured to mesh with the first planet gear 114-1 A and the third planet gear 114-1C. Further, the third planet gear 114-1C may be configured to mesh with the second gear 114- IB and the ring gear 106.

[029] Similarly, the first planet gear 114-2A may be configured to mesh with the sun gear 112 and the second planet gear 114-2B. Further, the second planet gear 114-2B may be configured to mesh with the first planet gear 114-2A and the third planet gear 114-2C. Further, the third planet gear 114-2C may be configured to mesh with the second gear 114-2B and the ring gear 106. [030] Further, the first planet gear 114-3A may be configured to mesh with the sun gear 112 and the second planet gear 114-3B. Further, the second planet gear 114-3B may be configured to mesh with the first planet gear 114-3A and the third planet gear 114-3C. Further, the third planet gear 114-3C may be configured to mesh with the second gear 114-3B and the ring gear 106.

[031] Each set of planet gears, i.e, the first planet gear 114A, the second planet gear 114B, and the third planet gear 114C may be mounted on an associated carrier arm of the plurality of carrier arms 110. For example, the first planet gear 114-1A, the second planet gear 114-1B, and the third planet gear 114- 1C may be mounted on the first carrier arm 110-1. The first planet gear 114-2A, the second planet gear 114-2B, and the third planet gear 114-2C may be mounted on the second carrier arm 110-2. The first planet gear 114-3A, the second planet gear 114-3B, and the third planet gear 114-3C may be mounted on the third carrier arm 110-3.

[032] It may be noted that each set of plurality of planet gears may include three to six planet gears 114. Accordingly, each carrier arm 110 may include multiple three to six slots 116 for accommodating the planet gears. For example, as shown in FIG. 3, each carrier arm 110 may include multiple six slots 116 for accommodating the planet gears.

[033] Referring back to FIGS. 1-2, the plurality of sets of planet gears

114 may include three sets of planet gears 114A, 114B and 114C of different radius. As shown, each set of the planet gears may include thee gears, each of same radius. The first radius is smaller than the second radius, and the second radius is smaller than the third radius. The radius of the first planet gear, second planet gear and third planet gear may be unique relative to each other. The set of planet gears 114A with the smallest radius may be in mesh with sun gear 112 and the set of planet gears 114C with the largest radius may be in mesh with the ring gear 106.

[034] Each carrier arm of the plurality of carrier arms 110 may include a plurality of slots 116 as shown in figure, for mounting a plurality of axles 118. Each carrier arm of the plurality of carrier arm 114 may have more than three slots 116. Each of the planet gear 114 may be mounted on an associated carrier arm via associated axle. Each planet gear may be free to rotate with respect to their mounting axles on the carrier arm.

[035] The gear system 100 may further include a plurality of axles 118 to mount the plurality of planet gears. These axles may be mounted on the associated carrier arms via the slots provided on the associated carrier arm. Each of the first axle, the second axle, and the third axle may be mounted on the associated carrier arm 110 via a slot of the plurality of slots 116.

[036] By way of an example, the first planet gear 114A may be mounted on the associated carrier arm 110-1 via the axle 118, and this axle 118 may be mounted on the associated carrier arm 110 via the first slot 116. Similarly, the second planet gear 114B may be mounted on the associated carrier arm via another axle 118, and this axle 118 may be mounted on the associated carrier arm via the second slot 116. Likewise, the third planet gear 114C may be mounted on the associated carrier arm 110 via a yet another axle 118, and this axle 118 may be mounted on the associated carrier arm via the third slot 116.

[037] It may be noted that the position of the first planet gear 114A, the second planet gear 114B, and the third planet gear 114C may be changeable on the associate carrier arm 110. Further, it may be possible to change the size (radius) of the first planet gear 114A, the second planet gear 114B, and the third planet gear 114C. In other words, it may be possible to remove the set of planet gears (i.e., first planet gear 114A, the second planet gear 114B, and the third planet gear 114C) from the carrier shaft 110 and replace with the another set of planet gears having different dimensions. For example, one combination of the radius of the set planet gears (i.e., first planet gear 114A, the second planet gear 114B, and the third planet gear 114C) may be 2 centimeters (cms), 4 cms, and 6 cms, respectively. As such, the slots 116 for the first planet gear 114A and the second planet gear 114B may be separated by 6 cms, and the slots for the second planet gear 114B and the third planet gear 114C may be separated by 10 cms. Another combination of the radius of the set planet gears (i.e., first planet gear 114 A, the second planet gear 114B, and the third planet gear 114C) may be 1 cm, 3 cms, and 8 cms, respectively. As such, the slots 116 for the first planet gear 114A and the second planet gear 114B may be separated by 4 cms, and the slots for the second planet gear 114B and the third planet gear 114C may be separated by 11 cms.

[038] It may be understood that once the power input is given to rotate the carrier 102, this rotation of the carrier may get transmitted to the plurality of the carrier arms 110 on which the planet gears are assembled via axles.

[039] Due to the different radii of the first planet gear 114 A, the second planet gear 114B, and the third planet gear 114C, the speed (RPM) of the sun gear 112 may increase with respect to the speed (RPM) of the carrier 102 or the plurality of the planet gears 114.

[040] In some embodiments, the gear system 100 may also be configured to reduce revolutions per minute at the output. For obtaining this, the sun gear 112 may be configured to act as a driver, and input shaft may be connected to the sun gear 112. Accordingly, the output of reduced speed may be obtained at the carrier 102, i.e. the ring gear 106, as per the load/torque requirement.