DESC:FORM 2
THE PATENTS ACT, 1970
(39 of 1970)
and
THE PATENTS RULE, 2003
COMPLETE SPECIFICATION
(See section 10, rule 13)
1. TITLE OF THE INVENTION
AN INTER LOCKING MECHANISM FOR AUTOMATED MANUAL TRANSMISSION IN MOTOR VEHICLE
2. APPLICANT
(a) Name (b) Nationality (c) Address
Knorr-Bremse Systems for Commercials Vehicles India Pvt. Ltd. An Indian Company Survey No.276, Village Mann,
Hinjawadi, Phase II, Taluka Mulshi, Pune -411057 Maharashtra, India.

3.PREAMBLE TO THE DESCRIPTION
PROVISIONAL
The following specification describes the invention COMPLETE
The following specification particularly describes the invention and the manner in which it is to be performed.

FIELD OF THE INVENTION
The present invention relates to automated manual transmission in vehicles and more particularly relates to an automated manual transmission with a novel interlocking mechanism that enables precise gear selection while driving the motor vehicle.
BACKGROUND OF THE INVENTION
Automated Manual Transmission (AMT) refers to a type of transmission system that integrates both manual and automatic transmission features. This includes automatic actuation for managing both gear shifting and clutch operation and is well suited for motor vehicles. It utilizes automated mechanisms to handle clutch engagement and gear shifting, making driving easier by reducing the need for manual coordination of clutch pedal and gear lever movements. This type of transmission aims to combine the fuel efficiency of a manual transmission with the convenience of an automatic transmission. In an AMT, the gear changes are processor-controlled, enabling smoother shifts and potentially enhancing driving comforts, especially in stop-and-go traffic situations.
The AMT currently, comprises of a control unit or electronic circuit unit that receives inputs from various sensors, such as vehicle speed, throttle position, engine RPM, etc. and, calculates the optimal time to shift the gears and control the clutch engagement based on these inputs. It further comprises a gear shifting mechanism operated by either hydraulic or electronic solenoids to control the movement of shift forks or rails, allowing the transmission to switch between different gear ratios, a clutch actuation mechanism that controls the clutch engagement without the need for a clutch pedal by means of a hydraulic or electromechanical actuator, a gear train unit having a set of gears that provide different gear ratios for driving at various speeds, a clutch system for engaging and disengaging the power transmission between the engine and transmission, a manual override unit allowing the driver to manually control gear changes in situations where they want more control, such as when driving on steep inclines, a synchromesh unit that allows the gears to synchronize their speeds before engagement, reducing grinding and wear during shifting and a hydraulic system to facilitate the movement of clutch actuators, gear shift mechanisms, and other components requiring fluid control. Here, the gear train is shifted using the shift actuation mechanism to select the appropriate gear ratio. The clutch system having a clutch assembly that can include components like clutch disc, pressure plate, release bearing, and flywheel.
When operating a vehicle equipped with an Automated Manual Transmission (AMT), seamless and uninterrupted gear shifting is expected. However, during the gear-shifting process aimed at reaching the desired gear position, certain challenges can arise, particularly, in automatic manual transmission while shifting the gears in desire gear position, the process of shifting of gears faces below extremity. To ensure the expected functionality, a locking mechanism must be in place to firmly secure the adjacent shift rail in the desired gear position during shifting. However, if manufacturing constraints prevent the maintenance of this locking mechanism within the required tolerance limits, it can lead to an undesired scenario where two gear positions are engaged simultaneously. Such an occurrence is far from ideal as it can result in transmission damage and improper gear shifting, causing sudden jerking of the vehicle and discomfort for the driver.
The locking mechanism utilized in AMTs features a complex design and manufacturing process, resulting in higher production costs. Furthermore, during maintenance procedures, the entire assembly must be disassembled, which is time-consuming and is further complicated by the requirement for specialized tools. As a result, the current AMT system's locking mechanism proves both labor-intensive and costly to manufacture due to its intricate structure. Additionally, the assembly of this locking mechanism is intricately interconnected with the main assembly, which itself is multifaceted. As a result, servicing the locking mechanism becomes time-consuming, necessitating the complete disassembly of the assembly and the use of specialized tools.
Accordingly, there exists a need to provide an interlocking mechanism for automated manual transmission in motor vehicles, which overcomes the above-mentioned drawbacks.
OBJECTS OF THE PRESENT INVENTION
An object of present invention is to provide a modular and robust locking mechanism that effectively secures the shift rails and blocks to the locking device, thus overcome limitations of prior art systems.
Another objective of the present invention is to achieve precise self-alignment and guidance that eliminates any play between the shift finger and shift block in AMT.
Yet, another objective of the present invention is to provide a rolling assembly between the locking device and housing in an AMT to reduce the sliding friction between two surfaces and prevent heat generation. This results in precise gear selection and shifting.
Yet, another objective is to ensure that the locking mechanism is easy to manufacture, assemble, and service, with a simple and cost-effective construction.
SUMMARY OF THE INVENTION
The present invention provides an interlocking mechanism for Automatic Manual Transmission systems in motor vehicle that can be fitted easily on gear box which is not dependent on main assembly. The interlocking mechanism comprising a housing configured to accommodate a plurality of shift blocks with rails that is structured to receive a shift finger therein, and a locking device securely placed on a slot provided on the housing. The locking device is configured to receive the shift finger through an elongated opening thereon and allow to get locked with one of the adjacent shift blocks in a plurality of shift block with rails based on the desired gear position. The locking device is provided with, a rolling assembly for eliminating friction between the surface of the shift finger and the locking device when in contact, and a detent assembly secured on two sides thereof. The detent assembly is configured to eliminate play between the shift finger and shift block in the plurality of shift block with rails upon the shift finger in neutral gate position and eliminates play between shift block in the plurality of shift block with rails and locking device, upon the shift finger in active gear position.
The locking device is configured to enable precise selection of gear position while driving the vehicle by limiting the sliding motion of one shift block relative to another within the plurality of shift block with rails and allowing movement of only one rail at a time and blocking the remaining rails due to the locked position of the locking device with the housing.
BRIEF DESCRIPTION OF THE INVENTION
The objects and advantages of the present invention will become apparent when the disclosure is read in conjunction with the following figures, wherein
Figure 1 illustrates a perspective view of an automated manual transmission (AMT) in motor vehicles, in accordance with an embodiment of the present invention,
Figure 2 illustrates a closer view of housing in AMT, in accordance with an embodiment of the present invention,
Figure 3a illustrates an exploded view of interlocking mechanism for automated manual transmission in unlocked state, in accordance with an embodiment of the present invention,
Figure 3b illustrates a closer view of interlocking mechanism in locked state having a shift finger engaged with the lock device, in accordance with an embodiment of the present invention,
Figure 4 illustrates a closer view of the shift finger engaged with the lock device in the interlocking mechanism as shown in figure 3b, in accordance with an embodiment of the present invention,
Figure 5a illustrates a pictorial view of the locking device with rolling assembly, in accordance with an embodiment of the present invention, and
Figure 5b illustrates an exploded view of the locking device in accordance with an embodiment of the present invention.
DETAILED DESCRIPTION OF THE INVENTION
The foregoing objects of the present invention are accomplished, and the problems and shortcomings associated with the prior art, techniques and approaches are overcome by the present invention as described below in the preferred embodiments.
The present invention provides an interlocking mechanism for Automatic Manual Transmission (AMT), which can be easily assembled without special tooling and provide smooth and individual gear shifting such as upshift and downshift as per desired speed yet overcome limitations of prior art systems. The design is capable of being fitted easily on gear box which is not dependent on main assembly.
In the following description, for the purpose of explanation, specific details are set forth in order to provide an understanding of the present invention. It will be apparent, however, to one skilled in the art that the present invention may be practiced without these details. One skilled in the art will recognize that embodiments of the present invention, some of which are described below, may be incorporated into several systems.
Furthermore, connections between components and/or modules within the figures are not intended to be limited to direct connections. Rather, these components and modules may be modified, re-formatted or otherwise changed by intermediary components and modules.
Throughout this application, with respect to all reasonable derivatives of such terms, and unless otherwise specified (and/or unless the context clearly dictates otherwise), each usage of:
“a” or “an” is meant to read as “at least one.”
“the” is meant to be read as “the at least one.”
References in the present invention to “one embodiment” or “an embodiment” mean that a particular feature, structure, characteristic, or function described in connection with the embodiment is included in at least one embodiment of the invention. The appearances of the phrase “in one embodiment” in various places in the specification are not necessarily all referring to the same embodiment.
As used in the description herein and throughout the claims that follow, the meaning of "a, an," and "the" includes plural reference unless the context clearly dictates otherwise. Also, as used in the description herein, the meaning of "in" includes "in" and "on" unless the context clearly dictates otherwise.
Exemplary embodiments will now be described more fully hereinafter with reference to the accompanying drawings, in which exemplary embodiments are shown. This invention may, however, be embodied in many different forms and should not be construed as limited to the embodiments set forth herein. These embodiments are provided so that this invention will be thorough and complete and will fully convey the scope of the invention to those of ordinary skill in the art.
Moreover, all statements herein reciting embodiments of the invention, as well as specific examples thereof, are intended to encompass both structural and functional equivalents thereof. Additionally, it is intended that such equivalents include both currently known equivalents as well as equivalents developed in the future (i.e., any elements developed that perform the same function, regardless of structure).
While embodiments of the present invention have been illustrated and described, it will be clear that the invention is not limited to these embodiments only. Numerous modifications, changes, variations, substitutions, and equivalents will be apparent to those skilled in the art, without departing from the spirit and scope of the invention, as described in the claim.
The present invention is illustrated with reference to the accompanying drawings, throughout which reference numbers indicate corresponding parts in the various figures. These reference numbers are shown in brackets in the following description below and in the table below.
Table:
Component Name Component Number
Housing 1
Shift finger 2
Locking device 3
Shift block rail 4,5,6,7
Steel ball in detent 6
Detents 8
Rolling assembly 9
Referring to the figures from 1 to 5, an interlocking mechanism for Automatic Manual Transmission systems in motor vehicle (100) (“interlocking mechanism (100)” hereinafter) is shown, in accordance with the present invention. The interlocking mechanism comprises a housing (1), a shift finger (2), a locking device (3) and a plurality of shift block with rails (4,5,6,7) secured in the Automatic Manual Transmission system.
In one of the exemplary embodiments of the present invention, the housing (1) is placed over a plurality of shift blocks with rails (4,5,6,7) and is configured to receive a shift finger (2) therein. The housing (1) is designed with a slot for receiving the locking device (3) thereon.
The housing (1) is a protective casing that surrounds the individual components of a gearbox in the vehicle, providing physical protection and mechanical support thereto. The housing (1) is also designed to deliver lubricant to a plurality of bearings, dissipate heat from inside the gear drive by conducting through walls thereof. The housing (1) is mainly configured to support the torque loads produced by the gears and the internal loads which are produced by the operation of the components within the gear box. The internal loads created by the gearing are transferred to a shaft, which needs to be supported by the plurality of bearings, and further supported by the housing (1). Besides providing support to the load, the housing (1) ensures that the plurality of bearings are correctly positioned so that the shafts and gearing are aligned appropriately.
In one of the exemplary embodiments of the present invention, the housing (1) is provided with a vertical split, having a front and rear housing (1) to guide the shift rails with a guiding bush. In the embodiment, the shift rails are assembled with shift blocks and are movably secured in the housing (1).
The housing (1) is further provided with a slot to receive the locking device (3) therein. The slot is designed in such a way that it locks the shift movement of the locking device (3) in Y-Axis or the upshift / downshift), and moves only in X Axis with shift finger (2). Thus, the locking device (3) is configured to slide locking from one shift block to another shift block, which allows movement of only one rail at time, blocking remaining rails due to entangled position of locking device (3) with a main housing of the AMT. This prevents simultaneous shifting of multiple rails.
In one of the exemplary embodiments of the present invention, the locking device (3) is designed as a rectangular component with an elongated opening (32) at the centre and wings (33) on both the sides. The locking device (3) is designed in such a way that an extended part (31) of the rectangular shape is locked in the housing (1), which prevents any undesirable gear shifting.
In one of the exemplary embodiments of the present invention, the locking device (3) is securely placed in a slot provided on the housing (1) and is configured to receive the shift finger (2) through an elongated opening (32) thereon. The locking device (3) allows the shift finger (2) to get locked with one of the adjacent shift blocks in a plurality of shift block with rails (4,5,6,7) based on the desired gear position.
In one of the exemplary embodiments of the present invention, the locking device (3) is designed in such way that an extended part (31) on both the sides is locked in a slot provided on housing (1), which prevents gear shifting.
The locking device (3) is configured to slide locking from one shift block to another shift block with the shift finger, which may allow movement of one shift rail at a time, blocking remaining rails due to entangled position of locking device (3) with the main housing of the AMT. This prevents simultaneous shifting of multiple rails, even if shift finger (2) position comes in between two shift blocks shifting of gear may not happen. In the embodiment, the shift finger (2) is guided in the locking device and selects and shift the gear when the vehicle operator moves the gear selector lever.
The locking device (3) is secured in the housing (1) of the multi-rail Automatic Manual Transmission systems and is configured to receive the shift finger (2) such that an extended part of the locking device (3) locks with one of the adjacent shift block rails in a plurality of shift block with rails (4,5,6,7) in AMT. This happens during the neutral or in active gear position such as an upshift and downshift of the motor vehicle. In an implementation of the present invention, the locking is depending upon the desired functionality of the gear. The shift finger (2) and the shift block with rails (4, 5, 6, 7) are precisely aligned while maintaining a gap/space in between. This arrangement eliminates any potential slackness between them, both when in neutral and during active gear changes such as upshifting and downshifting of the motor vehicle.
The locking device (3) further comprises a rolling assembly and a detent assembly (8) secured on the surface. The rolling assembly is provided to eliminate friction between the surface of locking device (3) and the shift finger (2) when in contact. Further, the detent (8) also eliminates the play between shift block (4) and locking device (3), when shift finger (2) is in active gear position such as upshift and downshift of the motor vehicle. This facilitates precision selection and shifting of gear while driving the vehicle.
In one of the exemplary embodiments of the present invention, the rolling assembly comprises of at least four roller balls (9) that are securely placed within dedicated slots provided at four corners of locking device (3). The roller balls (9) are configured to eliminate the friction and heat gets generated due to contact between surfaces.
In one of the exemplary embodiments of the present invention, the locking device (3) is drilled to accommodate the rolling balls. In one of the exemplary embodiments of the present invention, the locking device (3) is also provided with crimping on the drill holes, so that once balls are assembled, they may be locked in the locking device for permanently. In the arrangement of the present invention, the locking device (3) is placed between gear shifter and housing (1), therefore only the rolling balls may come in contact with the surfaces of gear shifter and transmission housing. Thus, when slides between the surface of the gear shifting unit and the housing (1) the locking device (3) may experience rolling effect.
In one of the exemplary embodiments of the present invention, the detent assembly comprises a pair of detents (8) includes atleast two spring loaded harden steel balls secured on two elongated sides of the locking device (3). The steel balls are inserted into a dedicated cylindrical slot provided on two sides of the locking device (3). In the embodiment, the detent (8) is configured to ensure rolling effect and the spring therein eliminates the play between the shift finger (2) and the shift block (4), when the shift finger (2) is in neutral gate position.
In one of the exemplary embodiments of the present invention, the detent assembly (8) includes a grub screw with spring loaded harden steel ball. The steel ball ensures rolling effect and spring force may eliminate the play between the shift finger (2) and the shift block (4), when the shift finger (2) is in neutral gate position, hence precision selection and shifting of gear is possible.
The interlocking mechanism (100) of the present invention is a modular locking mechanism that gives a robust locking between the shift finger (2) and shift block with rails (4,5,6,7) in AMT and the locking device (3).
In the embodiment, each of the plurality of shift block rails (4,5,6,7) are interlocked simultaneously using locking device (3) that locates into the slot provided in the housing (1), and the shift finger (2) is guided in to locking device (3). The locking device (3) slides locking from one shift block rail (4) to another shift block rail (5), which may allow movement of only one rail at time and blocking the remaining rails due to entangled position of locking device (3) with main housing (1). This prevents simultaneous shifting of multiple shift block rails (4,5,6,7) even if the shift finger (2) position comes in between two shift block rail (4) such as 3rd/4th to 5th/6th or 3rd/4th to 1st /2nd or 1st/2nd to reverse shifting of the gear.
The locking device (3) is configured to enable precise gear selection while driving the vehicle by limiting the sliding motion of one shift block relative to another within the plurality of shift block with rails (4,5,6,7). This allows movement of only one rail at a time and blocking the remaining rails due to the locked position of the locking device (3) with the main housing (1). Thus, the locking device (3) prevents simultaneous shifting of multiple rails in the plurality of shift block with rails (4,5,6,7) even if the active shift finger (2) position comes in between two adjacent shift block rails (4) and restricts simultaneous shifting of gear. Consequently, this arrangement prevents the concurrent shifting of multiple shift block rails (4, 5, 6, 7), even if the shift finger's (2) position happens to be between two neighboring shift block rails (4), thereby prohibiting simultaneous gear shifting.
ADVANTAGES OF THE INVENTION
1. The interlocking mechanism (100) offers a simple and economical design, hence manufacturing cost is lower.
2. The interlocking mechanism can be assembled quickly and independently. As no dependency is required with main AMT assembly. No special tools and arrangement are needed for assembling the components.
3. The minimal number of parts and the simplicity of thew parts, the mechanism (100) reduces the cost impact of implementation when compared to present interlock systems.
4. The rolling assembly in the locking device (3) helps to reduce the friction between two sliding surfaces, and thereby eliminate the heat produced. This also reduces the line contact between roller ball (9) and housing surface (1) (Main case and main assembly) thus ensure smooth selection of gates.
5. The interlocking mechanism is a modular and robust design, in which self-alignment and guide eliminates play between shift finger (2) and shift block (4).
6. The modular construction of the interlocking mechanism makes the design suitable for easy and quicker serviceability.
The foregoing descriptions of specific embodiments of the present invention have been presented for purposes of illustration and description. They are not intended to be exhaustive or to limit the present invention to the precise forms disclosed, and obviously many modifications and variations are possible in light of the above teaching. The embodiments were chosen and described in order to best explain the principles of the present invention and its practical application, and to thereby enable others skilled in the art to best utilize the present invention and various embodiments with various modifications as are suited to the particular use contemplated. It is understood that various omissions and substitutions of equivalents are contemplated as circumstances may suggest or render expedient, but such omissions and substitutions are intended to cover the application or implementation without departing from the spirit or scope of the claims of the present invention.
,CLAIMS:We claim:
1. An interlocking mechanism for Automatic Manual Transmission systems in motor vehicle (100), the interlocking mechanism (100) comprising:
a housing (1), the housing (1) configured to accommodate a plurality of shift blocks with rails (4,5,6,7) that is structured to receive a shift finger (2) therein,
a locking device (3) securely placed on a slot provided on the housing (1), the locking device configured to receive the shift finger (2) through an elongated opening (32) thereon and allow to get locked with one of the adjacent shift blocks in a plurality of shift block with rails (4,5,6,7) based on the desired gear position, the locking device (3) is provided with,
a rolling assembly for eliminating friction between the surface of the shift finger (2) and the locking device (3) when in contact, and
a detent assembly (6) secured on two sides thereof to eliminate play between the shift finger (2) and shift block in the plurality of shift block with rails (4,5,6,7) upon the shift finger (2) in neutral gate position and eliminates play between shift block (4) in the plurality of shift block with rails (4,5,6,7) and locking device (3), upon the shift finger (2) in active gear position,
wherein the locking device (3) is configured to enable precise selection of gear position while driving the vehicle by limiting the sliding motion of one shift block relative to another within the plurality of shift block with rails (4,5,6,7), and allowing movement of only one rail at a time and blocking the remaining rails due to the locked position of the locking device (3) with the housing (1).
2. The interlocking mechanism for Automatic Manual Transmission systems in motor vehicle (100) as claimed in claim 1, wherein the selection of gear position includes a neutral gate position and active gear position such as upshift and downshift of the motor vehicle.
3. The interlocking mechanism for Automatic Manual Transmission systems in motor vehicle (100) as claimed in claim 1, wherein the shift finger (2) and shift block with rails (4,5,6,7) are aligned with a gap/space therebetween to restrict any play there between while the motor vehicle is in neutral gate position or in active gear position.
4. The interlocking mechanism for Automatic Manual Transmission systems in motor vehicle (100) as claimed in claim 1, wherein the rolling mechanism incudes at least four roller balls (9) securely placed within dedicated slots provided at four corners of locking device (3).
5. The interlocking mechanism for Automatic Manual Transmission systems in motor vehicle (100) as claimed in claim 1, wherein the rolling mechanism incudes crimping on the drill holes on four corners of the locking device (3), thus the balls are assembled on the drill holes for permanently.
6. The interlocking mechanism for Automatic Manual Transmission systems in motor vehicle (100) as claimed in claim 1, wherein the pair of detents (6) includes two spring-loaded harden steel balls that are secured within slots arranged on opposing sides of the locking device (3).
7. The interlocking mechanism for Automatic Manual Transmission systems in motor vehicle (100) as claimed in claim 6, wherein each of the two-spring loaded harden steel balls is inserted into a dedicated cylindrical slot provided on the side wings of the locking device (3).
8. The interlocking mechanism for Automatic Manual Transmission systems in motor vehicle (100) as claimed in claim 1, wherein the detent assembly (8) includes a pair of detents (8) having atleast two spring loaded harden steel balls secured on two elongated sides of the locking device (3).
9. The interlocking mechanism for Automatic Manual Transmission systems in motor vehicle (100) as claimed in claim 1, wherein the detent assembly (8) is cofigured to ensure rolling effect and the spring therein eliminates the play between the shift finger (2) and the shift block (4), when the shift finger (2) is in neutral gate position.
10. The interlocking mechanism for Automatic Manual Transmission systems in motor vehicle (100) as claimed in claim 1 is a modular locking mechanism that is configured to provide a robust locking between the shift finger (2) and shift block with rails (4,5,6,7) in AMT and the locking device (3).
11. The interlocking mechanism for Automatic Manual Transmission systems in motor vehicle (100) as claimed in claim 1, wherein the locking device (3) is a rectangular component with an elongated opening (32) at the centre and wings (33) on both the sides.
12. The interlocking mechanism for Automatic Manual Transmission systems in motor vehicle (100) as claimed in claim 10, wherein the locking device (3) is designed in such a way that an extended part (31) of the rectangular shape is locked in the housing (1), that prevents any undesirable gear shifting.
Dated this on 1st day of September, 2023

Ragitha K
Agent for Applicant
(IN/PA/2832)