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Title:
BEVEL-PINION GEAR SET BASED COUPLED TORQUE STEERING SYSTEM FOR REVERSE TRIKES
Document Type and Number:
WIPO Patent Application WO/2019/167078
Kind Code:
A1
Abstract:
This patent discloses non-tilting bevel-pinion gear set based coupled torque steering system for reverse trikes. Steerer rod at the center, and steerer rod controlling the wheels are connected to bevel-pinion gear set each set consisting of six zerol bevel gears. Steerer rod at the center upon rotation via handle rotates coaxial bevel gear which in turn rotates pinion bevel gear engaged with it. Pinion gear at the center then rotates pinion gear of the gear set of the steering system at each of the wheels via a transmission shaft which in turn rotates the bevel gear attached to wheels, thus rotating the wheels. This steering system can also used in a four wheeler.

Inventors:
GAUTAM, Ravi Shankar (Rajendrapath Near Kabir Paan shop, Nai Godam, Gaya 1, 823001, IN)
Application Number:
IN2019/050170
Publication Date:
September 06, 2019
Filing Date:
February 28, 2019
Export Citation:
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Assignee:
GAUTAM, Ravi Shankar (Rajendrapath Near Kabir Paan shop, Nai Godam, Gaya 1, 823001, IN)
International Classes:
B62K5/027; B62K5/02
Foreign References:
FR3055125A12018-02-23
GB102110A1916-11-16
Download PDF:
Claims:
Claims

[Claim 1] Coupled torque steering system comprising bevel pinion central steering system, bevel-pinion left wheel steering system, bevel-pinion right wheel steering system and steer transmission mechanism.

[Claim 2] Right wheel steering system and left wheel steering system claimed in [Claim 1] are located on the right and left side respectively on the front part of the reverse trike with each of them comprising a wheel, steering fork, head tube, tubular cage and bevel-pinion gear set wherein

wheel is preferably of diameter less than the height of seat;

steering fork is a rigid/ suspension fork with steerer rod connected at its crown and fork blades at their ends holding the wheel at the ends of its axle; head tube consists of two vertical tubes separated by distance of bevel-pinion gear set encasing the steerer rod with the help of ball bearings;

bevel-pinion gear set consists of two coaxially parallel bevel gears upper and lower bevel gears, a pair of pinion bevel gears on the front, rear left and right side of the steerer rod;

tubular cage consists of three C-shaped rods and two L-shaped rods which directly or indirectly holds the pinion bevel gears in their designated places.

[Claim 3] Bevel-pinion gear set for the wheels mentioned in [Claim 2] is configured such that upper bevel gear are coaxially mounted on the respective steerer rod with the help of ball bearings and lower bevel gear is coaxially fixedly connected to the steerer rod;

all the pinion bevel gear are oriented so that each have its axis perpendicular to the axis of corresponding steerer rod;

pinion bevel gear on each side of the steerer rod is engaged with upper bevel gear and lower bevel gear;

pinion bevel gears on front, rear and left side of the steerer rod on the left wheel is connected to horizontal rod attached to tubular cage via ball bearings while pinion bevel gear on the right side of the steerer rod of the left wheel is held in place by tubular cage via steer transmission mechanism mention in [Claim 1]; pinion bevel gears on front, rear and right side of the steerer rod of the right wheel is connected to horizontal rod attached to tubular cage via ball bearings while pinion bevel gear on the left side of the steerer rod of the right wheel is held in place by tubular cage via steer transmission mechanism mention in [Claim 1] wherein C-shaped rods hold front, rear and outward pinion bevel gears in their place via rod and ball bearing and two L-shaped rods are used to hold head tubes of streer transmission mechanism.

[Claim 4] Tubular cage for right wheel is configured such that

it has one C-shaped rod on front side of the right wheel bevel-pinion gear set, with their upper and lower ends attached to upper and lower sections, respectively, of the right wheel head tube and front pinion bevel gear of right wheel, mentioned in [Claim 3], journalled to a horizontal rod extending from its vertical middle arm via ball bearing;

it has one C-shaped rod on rear side of the right wheel bevel-pinion gear set, with their upper and lower ends attached to upper and lower sections, respectively, of the right wheel head tube and rear pinion bevel gear of right wheel, mentioned in [Claim 3], journalled to a horizontal rod extending from its vertical middle arm via ball bearing;

it has one C-shaped rod on right side of the right wheel bevel-pinion gear set, with their upper and lower ends attached to upper and lower sections, respectively, of the right wheel head tube and right pinion bevel gear of right wheel, mentioned in [Claim 3], journalled to a horizontal rod extending from its vertical middle arm via ball bearing;

one L-shaped rod on the left upper side of the steerer rod with its end attached to right steer arm of steer transmission mechanism mentioned in [Claim 1] and upper section of head tube;

one L-shaped rod on the left lower side of the steerer rod with its end attached to right steer arm of steer transmission mechanism mentioned in [Claim 1] and lower section of head tube.

[Claim 5] Tubular cage for the left wheel are configured such that for

it has one C-shaped rod on front side of the left wheel bevel-pinion gear set, with their upper and lower ends attached to upper and lower sections, respectively, of the left wheel head tube and front pinion bevel gear of left wheel, mentioned in [Claim 3], journalled to a horizontal rod extending from its vertical middle arm via ball bearing;

it has one C-shaped rod on rear side of the left wheel bevel-pinion gear set, with their upper and lower ends attached to upper and lower sections, respectively, of the left wheel head tube and rear pinion bevel gear of left wheel, mentioned in [Claim 3], journalled to a horizontal rod extending from its vertical middle arm via ball bearing;

it has one C-shaped rod on left side of the left wheel bevel-pinion gear set, with their upper and lower ends attached to upper and lower sections, respectively, of the left wheel head tube and left pinion bevel gear of left wheel, mentioned in [Claim 3], journalled to a horizontal rod extending from its vertical middle arm via ball bearing;

one L-shaped rod on the right upper side of the steerer rod with its end attached to left steer arm of steer transmission mechanism mentioned in [Claim 1] and upper section of head tube;

one L-shaped rod on the right lower side of the steerer rod with its end attached to left steer arm of steer transmission mechanism mentioned in [Claim 1] and lower section of head tube.

[Claim 6] Central steering system claimed in [Claim 1] located on centre of the front part of the reverse trike, comprises, central steering shaft, central head tube, central tubular cage and central bevel-pinion gear set wherein

central steering shaft is a straight shaft with handle at its top;

central head tube consists of two vertical tubes as upper section and lower section separated by distance of central bevel-pinion gear set encasing the central steering shaft with the help of ball bearings with upper section connected at its rear side to the top tube of the reverse trike and lower section at its rear side is connected to the down tube of the reverse trike;

central bevel-pinion gear set consists of two coaxially parallel bevel gears upper and lower bevel gears, a pinion bevel gear on the front, rear, left and right side of the central steering shaft; central tubular cage consists of two C-shaped rods and four L-shaped rods which directly or indirectly holds the pinion bevel gears in their designated places.

[Claim 7] Central bevel-pinion gear set mentioned in [Claim 5] is configured such that

upper bevel gear are coaxially fixedly connected to the central steering shaft and lower bevel gear is coaxially mounted on the respective central steering shaft with the help of ball bearings;

all central pinion bevel gears are oriented so that each have its axis perpendicular to the axis of central steering shaft;

pinion bevel gear on each side of the central steering shaft is engaged with upper bevel gear and lower bevel gear;

pinion bevel gears on front and rear side of the central steering shaft is connected to horizontal rod attached to vertical rods of tubular cage via ball bearings while pinion bevel gear on the left and right side of the central steering shaft is held in place by tubular cage via steer transmission mechanism mentioned in [Claim 1]

[Claim 8] Central tubular cage is configured such that

it has one C-shaped rod on front side of the central bevel-pinion gear set, with their upper and lower ends attached to upper and lower sections, respectively, of the central head tube and front pinion bevel gear, mentioned in [Claim 7], journalled to a horizontal rod extending from its vertical middle arm via ball bearing;

it has one C-shaped rod on rear side of the central bevel-pinion gear set, with their upper and lower ends attached to upper and lower sections, respectively, of the central head tube and rear pinion bevel gear, mentioned in [Claim 7], journalled to a horizontal rod extending from its vertical middle arm via ball bearing;

one L-shaped rod on the left upper side of the central gear set with its end attached to left steer arm of steer transmission mechanism mentioned in claim [1] and upper section of central head tube;

one L-shaped rod on the left lower side of the central gear set with its end attached to left steer arm of steer transmission mechanism mentioned in [Claim 1] and lower section of central head tube; one L-shaped rod on the right upper side of the central gear set with its end attached to right steer arm of steer transmission mechanism mentioned in [Claim 1] and upper section of central head tube and

one L-shaped rod on the right lower side of the central gear set with its end attached to right steer arm of steer transmission mechanism mentioned in [Claim 1] and lower section of central head tube.

[Claim 9] Central steering system is coupled with left wheel steering system and right wheel steering system via steer transmission mechanism mentioned in [Claim 1]

[Claim 10] Steer transmission mechanism mentioned in [Claim 1] and [Claim 9] consists of two transverse straight shafts, one on right side of central gear set coaxially connecting right central bevel pinion gear to the left pinion bevel gear of right wheel, one on left side of central gear set coaxially connecting left bevel pinion gear to the right pinion bevel gear of left wheel, with each transmission shaft encased in head tube arms via ball bearings wherein

head tube arms on the left side and right side are connected at their rear side to top tube via appropriately bent rods.

[Claim 11] Handle claimed in [Claim 2] is preferably dutch style parallel handlebars with its stem connected to the upper end of central steering shaft claimed in [Claim 3], is located above the front end of the top tube of reverse trike at a height around the height of seat.

[Claim 12] According to one variation in bevel-pinion gear set used in central, left and right gear set described above, in central gear set we can have front and rear gears as bevel gears and top and bottom gears as pinion bevel gears, to provide rider more leg space.

Description:
Title of Invention: Bevel-Pinion gear set based Coupled Torque Steering System for Reverse

Trikes

Field of Invention

[01] Non-tilting steering system for reverse trike.

Background of Invention

[02] It is obvious that reverse trikes are more safe and stable than bikes and conventional trikes. Reverse trikes have many mechanical advantages over conventional trikes which include stability, traction in uphills and steerability. But providing an efficient steering mechanism for reverse trikes is a challenge. In recent past many models of reverse trikes have come up in the public domain offering tilting steering system. Tilting steering system has many issues which includes traction as well as ground clearance while cornering around a turn. Non-tilting steering system for reverse trikes have drawn little attention as it is understood by majority of folks that rack and pinion steering mechanism used in cars is sufficient for the purpose. But it has its own issues which includes big reduction ratio and too complex mechanism to handle on a trike. Non-tilting steering system is provided by Newton reverse trikes. It employs pitman arm to swing the kingpin attached to spindle mounted on each of the two front steer wheels.

Technical Problem

[03] Steering mechanism of reverse trike or four wheelers have externally moving parts in the form of steer transmission rods. It may be huge disadvantage in case of uneven land mass caused during snow fall.

[04] Rotation motion is converted into translational motion which is then converted back to rotation.

[05] Non-tilting steering mechanism in Newton reverse trike, applies the steering torque on the two wheels either from the front side of the head tube or rear side of the head tube due to which force gets exerted on the head tube rearward or forward direction respectively, thus making it difficult to operate as compared to steering system for a bicycle. In bicycles steering torque applied on the wheel is symmetric along the head tube. Summary of Invention

[06] One of our objective is to provide steering system for reverse trike which is as ergonomic to operate as that of a bicycle.

To achieve this objective steering system for reverse trike is designed such that two front wheels can be transversely rotated using coupled torque. Steering torque is applied on each of the front wheels symmetrically on both ends of the axle and symmetrically on front and rear side of the steerer rods, thereby providing easy and stable maneuverability to the steering system. Head tube is proportional to the length of steerer rod to provide sturdiness to steerer rod.

Wheels can be turned by 360 degree.

[07] Rotation steering action at the handle is transmitted as steering action on the wheel

through rotation motion and is not converted into translational motion as intermediate phase.

[08] It has no externally moving parts.

Brief Description of Drawings

[09] [Fig. 1] and [Fig. 2] Side and Top view respectively of reverse trike with bevel-pinion gearset based coupled torque steering system according to this invention.

[10] [Fig. 3] and [Fig. 4] Rear and top view respectively of bevel-pinion gearset based

coupled torque steering system according to this invention.

[11] [Fig. 5] Steering mechanism according to this invention without head tubes.

[12] [Fig. 6] Central, left and right steerer rods.

[13] [Fig. 7] and [Fig. 8] Top and bottom view of central, left and right bevel-pinion gearset used as in steering mechanism according to this invention.

[14] [Fig. 9] Central, left and right wormface gearset used as in steering mechanism without head tube arms according to this invention.

[15] [Fig. 10] Blown out image of central bevel-pinion gearset

[16] [Fig. 11] Blown out image of left bevel-pinion gearset

[17] [Fig. 12] Reverse trike with rotated front wheels due to steering action by steering

system according to this invention.

[18] [Fig. 13] and [Fig. 14] Top and bottom view of central, left and right bevel-pinion

gearset used in steering mechanism with variation according to this invention. Description of Embodiments

[19] As shown in [Fig. 1] and [Fig. 3], bevel-pinion gear set based coupled torque steering system for reverse trike (1) with top tube (TT) and down tube (DT), according to this invention comprises central steering system (CSS), left wheel steering system (LSS), right wheel steering system (RSS), steer transmission mechanism (STM), steering support mechanism (SSM).

Central steering system

[20] As shown in [Fig. 1] and [Fig. 3], central steering system (CSS) consists of central

steering shaft (CST), central head tube (CHT), central gear set and central tubular cage (CTC).

[21] As shown in [Fig. 1] and [Fig. 3], central steering shaft (CST) is a straight shaft,

connected to a handle at its top, is located on the center of the front part of reverse trike.

[22] As shown in [Fig. 1] and [Fig. 3], central head tube (CHT) is a set of two sections of vertical tubes, upper section (CHT1) and lower section (CHT2) separated by distance equal to the height of central gear set with each section coaxially holding the central steering shaft using ball bearings and upper section on its rear attached to top tube (TT) and lower section attached on its rear side to down tube (DT).

[23] As shown in [Fig. 3], [Fig. 7] and [Fig. 10], central gear set consists of two coaxially parallel horizontal bevel gears (CBG1) and (CBG2) coaxially mounted on the central steering shaft, a pinion bevel gear (CPB1) on the front, a pinion bevel gear (CPB2) on the rear, a pinion bevel gear (CPB3) on the left and a pinion bevel gear (CPB4) on the right side of the steering shaft with each pinion bevel gear having axis perpendicular to the axis of steering shaft. As shown in [Fig. 3], [Fig. 5] and [Fig. 8], bottom bevel gear (CBG2) is coaxially mounted on steering shaft via ball bearing so that it is free to rotate. Top bevel gear (CBG1) is coaxially fixedly connected to the central steering shaft. As shown in [Fig. 3], [Fig. 5] and [Fig. 7], axis of each of the pinion bevel gears is perpendicular to that of central steering shaft. Pinion bevel gears (CPB1), (CPB2), (CPB3) and (CPB4) are meshingly engaged with bottom bevel gear and top bevel gear.

[24] As shown in [Fig. 3], central tubular cage (CTC) consists of two C-shaped rods and four L-shaped rods, surrounding central gear set, with one C-shaped rod on the front side of central gear set with its upper and lower ends connected to upper section (CHT1) and lower section (CHT2), respectively, of central head tube; one C-shaped rod on the rear side of central gear set with its upper and lower ends connected to upper section (CHT1) and lower section (CHT2), respectively, of central head tube; one L-shaped on upper right side of central gear set with its ends connected to right steer arm of steer transmission mechanism and upper section (CHT1) of central head tube; one L-shaped rod lower right side of central gear set with its ends connected to right steer arm of steer transmission mechanism and lower section (CHT2) of central head tube; one L-shaped upper left side of central gear set with its ends connected to left steer arm of steer transmission mechanism and upper section (CHT1) of central head tube; and one L- shaped rod on lower left side of central gear set with its ends connected to left steer arm of steer transmission mechanism and lower section (CHT2) of central head tube.

[25] As shown in [Fig. 3], [Fig. 7] and [Fig. 10], pinion bevel gears on front and rear side (CPB1) and (CPB2) are coaxially connected at their outer side to horizontal rods extending from the central tubular cage via ball bearings (CBB1) and (CBB2) respectively. Central pinion bevel gears (CPB3) and (CPB4) are held in place by steer transmission mechanism (STM).

Left wheel steering system

[26] As shown in [Fig. 1] and [Fig. 3], left wheel steering system consists of a wheel (LW), left steering fork (LSF), left head tube (LHT), left gear set and left tubular cage (LTC).

[27] As shown in [Fig. 1] and [Fig. 3], left wheel steering fork (LSF) is a rigid/ suspension fork with steerer rod (LSR) with fork blades at their ends holding the wheel (LW) at the ends of its axle. Left head tube (LHT) is a set of two sections of vertical tubes, upper section (LHT1) and lower section (LHT2) separated by distance equal to the height of central gear set with each section coaxially holding the central steering shaft using ball bearings.

[28] As shown in [Fig. 3], [Fig. 7], and [Fig. 11], left gear set consists of two coaxially

parallel bevel gears (LBG1) and (LBG2) coaxially connected to left steering shaft, a pinion bevel gear (LPB1) on the front, a pinion bevel gear (LPB2) on the rear, a pinion bevel gear (LPB3) on the left and a pinion bevel gear (LPB4) on the right side of the left wheel steerer rod with each pinion bevel gear having axis perpendicular to the axis of steering shaft. As shown in [Fig. 1], [Fig. 3] and [Fig. 5], bottom bevel gear (LBG2) is fixedly connected to the left wheel steerer rod (LSR) and top bevel gear (LBG1) is coaxially mounted on left wheel steerer rod (LSR) via ball bearing so that it is free to rotate. As shown in [Fig. 3], [Fig. 5], and [Fig. 11], axis of each of the pinion bevel gears is perpendicular to that of left steerer rod (LSR). Each of pinion bevel gears (LPB1) (LPB2) (LPB3) and (LPB4) is engaged with top and bottom bevel gear.

[29] As shown in [Fig. 1] and [Fig. 3], left tubular cage (LTC) consists of three C-shaped rods and two L-shaped rods, surrounding left wheel gear set, with one C-shaped rod on the front side of central gear set with its upper and lower ends connected to upper section (LHT1) and lower section (LHT2), respectively, of left wheel head tube; one C-shaped rod on the rear side of left wheel gear set with its upper and lower ends connected to upper section (LHT1) and lower section (LHT2), respectively, of left wheel head tube; one C-shaped rod on the left side of left wheel gear set with its upper and lower ends connected to upper section (LHT1) and lower section (LHT2), respectively, of left wheel head tube; one L-shaped on upper right side of left wheel gear set with its ends connected to right steer arm of steer transmission mechanism and upper section (LHT1) of left wheel head tube; one L-shaped rod lower right side of left wheel gear set with its ends connected to right steer arm of steer transmission mechanism and lower section (LHT2) of left wheel head tube.

[30] As shown in [Fig. 3], [Fig. 7] and [Fig. 10], left pinion bevel gears on front, rear side and left side (LPB1), (LPB2) and (LPB3), are coaxially connected at their outer side to horizontal rods extending from the central tubular cage via ball bearings (LBB1),

(LBB2) and (LBB3) respectively. Left pinion bevel gears (LPB2) and (LPB4) are held in place by steer transmission mechanism (STM).

Right wheel steering system

[31] As shown in [Fig. 1] and [Fig. 3], right wheel steering system (RSS) consists of a wheel (RW), left steering fork (RSF), left head tube (RHT), right gear set (RGS) and right tubular cage (RTC).

[32] As shown in [Fig. 1] and [Fig. 3], right steering fork (RSF) is a rigid/ suspension fork with steerer rod (RSR) with fork blades at their ends holding the wheel (RW) at the ends of its axle.

[33] As shown in [Fig. 1] and [Fig. 3], right head tube (RHT) is a set of two sections of

vertical tubes, upper section (RHT1) and lower section (RHT2) separated by distance equal to the height of right gear set with each section coaxially holding the central steering shaft using ball bearings. [34] As shown in [Fig. 3], [Fig. 7] and [Fig. 10], right gear set (RGS) consists of two coaxially parallel bevel gears (RBG1) and (RBG2) coaxially connected to right steering shaft, a pinion bevel gear (RPB1) on the front, a pinion bevel gear (RPB2) on the rear, a pinion bevel gear (RPB3) on the left and a pinion bevel gear (RPB4) on the right side of the right wheel steerer rod with each pinion bevel gear having axis perpendicular to the axis of steering shaft.

As shown in [Fig. 3] and [Fig. 5], bottom bevel gear (RBG2) is fixedly connected to the right wheel steerer rod (RSR) and top bevel gear (RBG1) is coaxially mounted on right wheel steerer rod (RSR) via ball bearing so that it is free to rotate.

As shown in [Fig. 3], [Fig. 7] and [Fig. 10], axis of each of the pinion bevel gears is perpendicular to that of right steerer rod (RSR). Each of pinion bevel gears (RPB1) (RPB2) (RPB3) and (RPB4) is engaged with top and bottom bevel gear.

[35] Right tubular cage (RTC) consists of three C-shaped rods and two L-shaped rods,

surrounding right wheel gear set, with one C-shaped rod on the front side of central gear set with its upper and lower ends connected to upper section (RHT1) and lower section (RHT2), respectively, of right wheel head tube; one C-shaped rod on the rear side of right wheel gear set with its upper and lower ends connected to upper section (RHT1) and lower section (RHT2), respectively, of right wheel head tube; one C-shaped rod on the right side of right wheel gear set with its upper and lower ends connected to upper section (RHT1) and lower section (RHT2), respectively, of right wheel head tube; one L- shaped on upper right side of right wheel gear set with its ends connected to right steer arm of steer transmission mechanism and upper section (RHT1) of right wheel head tube; one L-shaped rod lower right side of right wheel gear set with its ends connected to right steer arm of steer transmission mechanism and lower section (RHT2) of right wheel head tube.

[36] As shown in [Fig. 3], [Fig. 7] and [Fig. 10], right pinion bevel gears on front, rear side and right side (RPB1), (RPB2) and (RPB4) are coaxially connected at their outer side to horizontal rods extending from the central tubular cage via ball bearings (RBB1),

(RBB2) and (RBB3) respectively. Right pinion bevel gears (RPB3) are held in place by steer transmission mechanism (STM).

Steer Transmission Mechanism [37] Central steering system is coupled with left wheel steering system and right wheel steering system via steer transmission mechanism (STM). Steer transmission mechanism (STM) consists of two transverse straight shafts, one (TS1) on right side coaxially connecting bevel pinion gears (CPB3) and (LPB4), and one (TS2) on left side coaxially connecting bevel pinion gears (CPB4) and (RPB3), of the central gear set with transverse shaft (TS1) and (TS2) coaxially encased in head tube arms (TH1) and (TH2) respectively via ball bearings. Head tube arms on the left side and right side are connected at their rear side to top tube via rods left top tube arm (LTTA) and right top tube arm (RTTA) respectively.

Steer Operation

[38] On rotation in clockwise direction, handle causes bevel gear (CBG1) to rotate clockwise direction which in turn causes all the central pinion gears to rotate with the central pinion bevel gears (CPB3) rotating in direction opposite to that of (CPB4). Rotation of (CPB3) causes to rotate left wheel pinion gears (LPB4) respectively via transmission shafts which in turn causes left wheel bottom bevel gear (LBG2) to rotate in clockwise direction and thus steer left wheel in clockwise direction. Similarly rotation of (CPB4) causes to rotate right wheel pinion gears (RPB3) respectively via transmission shafts which in turn causes right wheel bottom bevel gear (RBG2) to rotate in clockwise direction and thus steer right wheel in clockwise direction. Central pinion gears (CPB1) and (CPB2) and central bottom bevel gear (CBG2) are auxiliary gears which help to couple the steering action of upper bevel gear (CBG1) between upper and lower side of pinion bevel gears (CPB2) and (CPB4). Left wheel pinion gears (LPB1), (LPB2) and (LPB3), and left upper bevel gears (LBG1) are auxiliary gears which help to couple the steering action of left wheel pinion bevel gears (LPB4). Similarly right wheel pinion gears (RPB1), (RPB2) and (RPB3), and left upper bevel gears (RBG1) are auxiliary gears which help to couple the steering action of left wheel pinion bevel gears (RPB4).

[39] Bevel-pinion gear set used in central, left and right gear set can have various variations.

According to one variation , as shown in [Fig. 13] and [Fig. 14], in central gear set front and rear gears are bevel gears and top and bottom gears are pinion bevel gears. In this variation rider will have more leg space.