Solenoid actuator-based control unit, electronic gearbox control mechanism and gearbox thereof

Abstract

The present invention relates to a solenoid actuator-based control unit for a drive train transmission unit or a gearbox of a commercial vehicle, comprising a solenoid actuator, which comprises an actuator rod configured to linearly reciprocate, wherein the actuator rod comprises a first end and a second end, wherein the actuator rod further comprises a magnet holder holding a magnet In an embodiment, an electronic gearbox control mechanism comprising the solenoid actuator-based control unit is disclosed. In another embodiment, a gearbox comprising the electronic gearbox control mechanism is disclosed.

Description

[0001] Hannover, 26.11.2024 IP, Pundareekam / Lu 304683-IN-NP ID 304683

[0002] SOLENOID ACTUATOR-BASED CONTROL UNIT, ELECTRONIC GEARBOX CONTROL MECHANISM AND GEARBOX THEREOF

[0003] Technical field of the invention

[0004] The present invention relates to a solenoid actuator-based control unit for a drivetrain transmission unit or a gearbox of a commercial vehicle, an electronic gearbox control mechanism and a gearbox thereof.

[0005] Background of the invention

[0006] Conventional automatic manual gearbox control mechanisms generally include integrated or separate actuators for performing a set of functions including select, shift and / or range. Such mechanisms are in principle justified for complex gear transmission ratios. However, for a further simplified drivetrain transmission units or gearbox mechanisms that are configured for achieving a relatively lower number of variations in the transmission ratios between an input and an output shaft of the drivetrain transmission unit, the input shaft of the drivetrain transmission unit is connected with either an electric motor shaft or an internal combustion engine output shaft either directly or indirectly. Thus, in theory, the input shaft of the drivetrain transmission unit almost always has a relatively higher rotational speed in comparison to the output shaft.

[0007] To control the relative speed differential or ratio between the input and output shafts of the drivetrain transmission unit, it is generally known to use gearshift mechanisms in the commercial vehicles that are operated using pneumatic or hydraulic forces. The demand of relatively higher forces to execute the gearshifts resulted in usage of the hydraulic or pneumatic actuators for performing both the select and / or shift functions before any gearshift is performed. Such existing solutions using the pneumatic or hydraulic actuators not only have higher constructional costs because of ensuring the structural integrity and sealing requirements but are also generally not necessary under certain use-case conditions. One such use-case condition is the lower number or variety of speed ratios to be achieved between the input and output shafts of the drivetrain transmission unit or the gearbox. Summary of the invention

[0008] In accordance with an embodiment of the present invention, a solenoid-based control unit adapted for a drivetrain transmission unit or a gearbox of a commercial vehicle is disclosed. The solenoid actuator-based control unit comprises a solenoid actuator actuator or a linear solenoid actuator, which in turn comprises a housing, and an actuator rod configured to linearly reciprocate at least partially within the housing. The actuator rod comprises a first end (which can be referred to as “select 1”) and a second end (which can be referred to as “select 2”), wherein the actuator rod further comprises a magnet holder holding a magnet, wherein the magnet holder is either coupled to or formed integrally with respect to the first end of the actuator rod, and wherein the second end of the actuator rod is arranged opposite to the first end of the actuator rod and is configured to either selectively or at least partially extend through an opening of the housing.

[0009] For the sake of understanding, the term “solenoid actuator-based control unit” may be interpretated as a control unit fitted with or comprising a solenoid actuator.

[0010] In order to understand the invention, it is necessary to define the solenoid actuator that is used in accordance with the requirements of the present invention. The conventional solenoid or linear actuators are used in precision engineering applications and other industrial applications. These actuators generally work based on the principle of converting an electric energy suppled via Direct Current (DC) to mechanical work output. An electric excitation coil and / or armature is used to move an electrically conductive and / or electromagnetically excitable actuator rod in a linearly reciprocating manner.

[0011] However, such solenoid or linear actuators have not been used in the shift control mechanisms of the gearbox controls at least partially because their use has been restricted for simple, but highly precise industrial applications. The inventors of the present invention have adapted and / or configured the solenoid actuators for use in a gearshift control mechanism. Thus, the technical advantage of the solenoid actuatorbased control unit of the present invention lies in particular with the adaptation or configuration of making the solenoid-based control unit for its use in the drivetrain transmission unit or gearbox of the commercial vehicle.

[0012] For instance, during the gearshift or the enablement of change in the speed ratio between an input and output shaft of the gearbox, it is necessary to firstly select one of the shift rods that facilitate performing the gearshift. And secondly, it is also necessary to determine that in fact the gearshift has occurred.

[0013] By providing the magnet holder at the first end of the actuator rod of the solenoid actuator and enabling the second end either selectively or at least partially extend through an opening of the housing, the solenoid actuator-based control unit of the present invention enables the determination of the current linear position of at least the actuator rod as well as enables or facilitates the selection of the appropriate shift rod among the plurality of gearshift rods down the line of shiftintg process. The determined current linear position of the actuator rod is then transmitted via a position sensor, such as a 2D and more preferably, a 3D Hall sensor. By this way, an electronic control unit (ECU) associated with, for instance, gearshift or even entire gearbox control can directly determine which of the shift rods has been engaged. Thereafter, depending on the position of any other shift actuator, the ECU can arrive, for instance, at a determination on which exact gear is currently engaged, by performing further necessary iterative operations. Thus, the solenoid actuator’s configuration or adaptation with the help of the magnet holder which is either coupled to or formed integrally with respect to the first end of the actuator rod of the solenoid actuator enables using the solenoid actuator-based control unit in the gearbox control mechanism.

[0014] In a particularly preferred embodiment, the position sensor is mounted on the housing of the solenoid actuator of the current embodiment of the present invention. This provides for an uninterrupted and direct access to the inductive signals emitted by the magnet mounted at the first end of the actuator rod.

[0015] In accordance with an embodiment of the present invention, the solenoid actuator is a push-pull solenoid actuator configured to reciprocate the actuator rod linearly in both a push-direction and a pull-direction. Further, the solenoid actuator is configured to at least partially extend the actuator rod through the opening (of the housing) during the push-direction movement. Using the push-pull solenoid actuator allows for a bidirectional activation of the actuator rod. Thus, when the gearshift requires to be performed, the actuator rod can either be extended or be retracted. To further clarify the orientation of the actuator rod with respect to the housing of the solenoid actuator, the actuator rod is able to exit (to whatsoever extent) outside the housing during the pushing action executed by the push-pull solenoid actuators. The structure of enabling the extension of the actuator rod, even if selectively and / or partially outside the housing, adds to the further adaption of the push-pull solenoid actuator or the solenoid actuator for its use the drivetrain transmission unit or the gearbox of a commercial vehicle, in particular for gear shifting purposes.

[0016] In accordance with the same or different embodiment to the one discussed above, the solenoid actuator-based control unit comprises the solenoid actuator that is configured to operate with a solenoid force at 5 - 70 N at 100% Duty Cycle and to operate with a solenoid force of 30- 350N at 5% Duty Cycle. This, the solenoid actuator of the specified force values at the corresponding duty cycles are adapted for the use in the gearshift control in the drivetrain transmission unit or gearbox of the commercial vehicle. The force delivery at the specified range of the corresponding duty cycle contributes to the adaptation of the solenoid actuator for the gearbox and / or gearshift control units or mechanisms as this would assist basic performance of the gearshift function.

[0017] Furthermore, in an exemplary embodiment of the present invention, the solenoid actuator is configured to have a stroke length of 5 - 50 mm.

[0018] In a yet another embodiment of the present invention, an electronic gearbox control mechanism for a drive train transmission unit or a gearbox of a commercial vehicle is disclosed. Said mechanism comprises a motor-based shift control unit, at least one shift rod configured to move depending on the movement derived from the motorbased shift control unit, a select rod arranged perpendicular to the at least one shift rod, and the solenoid actuator-based control unit according to any one of the embodiments described above and connected directly or indirectly with at least the select rod. The mechanism is characterized by the solenoid actuator which facilitates engagement or disengagement between the motor-based shift control unit and the at least one shift rod and controls the movement of the select rod by linearly reciprocating the actuator rod.

[0019] The perpendicularly arranged select rod is actuated by the solenoid actuator of the solenoid actuator-based control unit according to the present invention. While the motor-based shift control unit is connected directly or indirectly with the at least one shift rod among the plurality of shift rods, the actuation of a simple solenoid actuator results in the select rod choosing one of the shift rods for being connected with the motor-based shift control unit when there is more than one shift rod. The present embodiment of the electronic gearbox control mechanism utilizes not only costefficient, but also relatively constructionally simpler solenoid actuator replacing a traditional motor-based select controller or a pneumatic or hydraulic actuator used for actuating the select rod. Thus, for a simple gearbox requiring, for instance, four different speed ratios between the input and output shafts, the utilization of the solenoid actuator in the gearbox control mechanism provides for a simpler solution while attaining the same function as provided by the motor-based or pneumatic or hydraulic actuator.

[0020] In a preferred embodiment of the present invention, the electronic gearbox control mechanism with the motor-based shift control unit comprises an electric motor and a rack-and-pinion mechanism, and wherein the motor-based shift control unit is configured to move the engaged shift rod in a linearly translatory movement when the engagement between the motor-based shift control unit and the engaged shift rod is complete. The electric motor is preferably, a DC (Direct Current) motor operable through the ECU associated with the gearshift or a general ECU associated with the drivetrain transmission unit and / or gearbox. By this way, the sequence of operation, as soon as a particular target gear is determined, is to select and engage the shift rod whose movement would reach the target gear. Once this is performed, the electric motor through the rack-and-pinion mechanism transmits the work output to the engaged shift rod.

[0021] In a yet another preferred embodiment, the electrically activated gearbox control mechanism further comprises a locking mechanism that is controlled by the solenoid actuator for at least two positions, namely engaged or disengaged positions, depending on which the at least one shift rod is engaged with the motor-based shift control unit. In the current embodiment, the locking mechanism acts as a connecting interface between the actuator rod of the solenoid actuator and the select rod (whichever is engaged). This implies that the locking mechanism, depending on its axial position, is configured to engage one of the shift rods, if there are more than one shift rods.

[0022] In a still further embodiment of the present invention or the locking mechanism explained in relation to the above embodiment, the locking mechanism comprises a stopper pin with at least two arcuate shaped features and is adapted to move linearly from a first select position to a second select position and vice versa, wherein the gearbox control mechanism has at least two shift rods, and wherein at least one of the at least two shift rods can be selectively slidingly received at one of the at least two arcuate shaped features, respectively, depending on the latest position of the stopper pin. Preferably, the stopper pin is slidingly received within a keyway groove of a housing of the locking mechanism so that no rotational movement of the stopper pin is possible in relation to the housing the locking mechanism. The keyway groove within the housing of the locking mechanism maintains the radial position of the stopper pin with respect to the locking mechanism housing. The two arcuate shaped features of the stopper pin according to the present embodiment provides the profiles that are required for slidingly receiving the shift rods. In other words, when one of the arcuate shaped feature coincides with the shape of the one of the shift rods, the corresponding shift rod is allowed to slide in a shift direction along a receiving surface of the of the arcuate shaped feature. By this way, by merely moving the stopper pin due to the activation of the solenoid actuator, the stopper pin is enabled to block any movement of one of the at least two shift rods while the other of the at least two shift rods is allowed to move.

[0023] In accordance with one of the above embodiments of the present invention, the actuator rod of the solenoid actuator is coupled with the stopper pin through a coupling element such that the linear movement of the actuator rod can be transferred to the stopper pin. It is particularly advantageous when one end of the coupling element is removably connected with a help of a lock pin with the actuator rod and the other end is connected with the stopper pin. Both the pull and push movement of the actuator rod of the solenoid actuator is transferred to the stopper pin.

[0024] In accordance with one or more of the above embodiments, the stopper pin includes a hollow cylinder receiving a spring, wherein the spring extends and applies extension force on the stopper pin. In accordance with the present embodiment, the spring achieves the effect of retaining the position of the stopper pin with respect to the housing of the locking mechanism. If the actuator rod performs the pull function, the spring is compressed between the hollow cylinder and a pin. If the actuator rod performs the push function, the spring extends between the pin and the hollow cylinder of the stopper pin such that the desired position of the stopper pin is achieved faster.

[0025] In accordance with a particularly preferred embodiment of the present invention, the electronic gearbox control mechanism further comprises a position sensor for assisting in determining the gear that is currently engaged by the electronic gearbox control mechanism, and wherein the position sensor receives at least part of inductive signal from the magnet. It is particularly advantageous that the position sensor is directly mounted onto the housing of the solenoid actuator. This creates vicinity with respect to the magnet present within the housing of the solenoid actuator and induction signals are directly received by the position sensor. Moreover, the position sensor provides the latest position of the actuator rod of the solenoid actuator which in turn indicates which among the plurality of shift rods (when more than one shift rod is used) is currently engaged by the electric motor for performing the shift operation. Ultimately, this contributes to the precise electronic determination of the gear currently engaged by the gearbox.

[0026] In accordance with the above embodiment, in a particularly preferable implementation, the position sensor is a magnetically inducible sensor such as a Hall sensor. The Hall sensor can be a 3D Hall sensor in which translatory, rotatory and angular movements of the magnet or any signal sending device can be accurately perceived. In other words, the Hall sensor (the position sensor) according to the present embodiment is configured to detect translatory, rotatory and / or angular movements of the magnet or any signal sending device.

[0027] In accordance with one or more embodiments of the present invention, a gearbox is disclosed. The gearbox comprises an input shaft and output shaft, and is configured to achieve at least two different speed ratios between the input and output shafts. The gearbox also comprises the electronic gearbox control mechanism in accordance with any one of embodiments discussed above.

[0028] In a particularly advantageous implementation, the gearbox is configured to achieve at least four different speed ratios between the input and output shafts of the gearbox.

[0029] Furthermore, a commercial vehicle comprising the gearbox in accordance with any one of above embodiments is disclosed.

[0030] Brief description of the accompanying drawings

[0031] Fig. 1 illustrates a gearbox of a commercial vehicle along with a solenoid actuatorbased control unit and an electronic gearbox control mechanism in a perspective view in accordance with an embodiment of the present invention;

[0032] Fig. 2 illustrates an overview of the electronic gearbox control mechanism in a partly disassembled view in accordance with an embodiment of the present invention; and

[0033] Fig. 3 illustrates a solenoid actuator-based control unit in a cut-section along with a locking mechanism for performing a “select” function in accordance with an embodiment of the present invention. Detailed description of the accompanying drawings

[0034] In accordance with the embodiment associated with Fig. 1, an electronic gearbox control mechanism 100 for a drive train transmission unit or a gearbox 50 of a commercial vehicle 10 is disclosed.

[0035] Gearbox 50 comprising an input shaft IS and output shaft OS is disclosed. According to the present invention, gearbox 50 is configured to achieve at least two different speed ratios between the input and output shafts and comprises electronic gearbox control mechanism 100 as explained below. In particular, gearbox 50 is configured to achieve at least four different speed ratios between the input and output shafts of the gearbox. The different speed ratios are represented as first, second, third and fourth gear. Naturally, gearbox 50 is also configured to be at a “neutral” gear state so that no work output is transferred to the output shaft OS of gearbox 50.

[0036] Electronic gearbox control mechanism 100 of the present invention comprises a motor-based shift control unit 102, at least one shift rod 106 configured to move depending on the movement derived from the motor-based shift control unit 102, a select rod 108 arranged perpendicular to the at least one shift rod 106, for instance, along a first plane (see reference sign “P” in Fig. 1 ; note that reference plane P is shown in Fig. 1 to show the geometric orientation of rod 106 with respect to rod 108 even if the term “perpendicular” is self-explanatory from fig. 1 itself), and a solenoid actuator- based control unit 104 connected directly or indirectly with at least select rod 108. The details associated with solenoid actuator-based control unit 104 will be explained in association with Fig. 3 of the present application. Further, solenoid actuator 110 facilitates engagement or disengagement between motor-based shift control unit 102 and at least one shift rod and controls the movement of select rod 108 by linearly reciprocating actuator rod 120. As can be noticed from Fig. 1, when solenoid actuator 104 is activated, select rod 108 can assist in selectively engaging a particular shift rod 106 among two shift rods shown in Fig. 1, so that the linear or translatory movement received from motor-based shift control unit 102 can be transferred to shift rod 106 (the engaged one). This results in shift rod 106 moving in a direction parallel to arrow mark “D” marked in Fig. 1. Further details on how this occurs will be explained in the general working principle of the invention below.

[0037] Further, motor-based shift control unit 102 comprises an electric motor 112 and a rack-and-pinion mechanism 114 (the location of said rack-and-pinion mechanism is marked with reference sign 114), wherein motor-based shift control unit 102 is configured to move shift rod 106 (whichever shift rod that has been engaged with motor-based shift control unit 104, if more than one shift rod is preset) in a linearly translatory movement when the engagement between motor-based shift control unit 102 and shift rod 106 is complete.

[0038] In accordance with one or more preferred embodiments of the present invention, electronic gearbox control mechanism 100 further comprises a locking mechanism 116 that is controlled by solenoid actuator 110 for at least two positions, namely engaged or disengaged positions, depending on which at least one shift rod 106 is engaged with motor-based shift control unit 102. For instance, by this way, depending on whether solenoid actuator 110 is engaged or disengaged, locking mechanism 116 can engage the appropriate shift rod 106 to achieve a targeted gear, which is one of the speed ratios mentioned above (1st, 2nd, 3rd, 4thand neutral).

[0039] Fig. 2 illustrates an overview of electronic gearbox control mechanism 100 in a partly disassembled view in accordance with an embodiment of the present invention, and Fig. 3 illustrates a solenoid actuator-based control unit 104 in a cut-section along with locking mechanism 116 for performing a “select” function in accordance with an embodiment of the present invention.

[0040] Further, as can be taken from Figs. 2 and 3, locking mechanism 116 comprises a stopper pin 130 with at least two arcuate shaped features 132 and 134 and is adapted to move linearly from a first select position to a second select position and vice versa, wherein gearbox control mechanism 100 has at least two shift rods 106, and wherein at least one of the at least two shift rods 106 can be selectively slidingly received at one of at least two arcuate shaped features 132 or 134, respectively, depending on the latest or last achieved position of stopper pin 130. According to the preferred design shown in e.g., Fig. 3, two arcuate shaped features 132 and 134 are cuts or grooves formed on stopper pin 130. It is also preferred that the shape and dimensions of two arcuate shaped features 132 and 134 match the shape and dimensions of an outer surface of shift rods 106. When an appropriate arcuate shaped feature such as the one marked with reference sign “132” coincides axially with respect to a corresponding shift rod 106, the corresponding shift rod can pass through the arcuate shaped feature when it is moved in a direction parallel to arrow mark ‘D’ as marked, for instance, in Figs. 1 and 2. In general, the arrow mark with reference sign “D” relates to a shift direction i.e. , the direction in which at least one of shift rods 106 should move to perform a gear shifting function.

[0041] By this way, when stopper pin 130 is moved to an appropriate position in the direction along or parallel to the direction marked with arrow mark “M” in Fig. 3, one of the shift rods 106 is allowed to linearly reciprocate whereas the other is blocked. In accordance with the embodiment shown in Fig. 3, shift rod 106 marked with reference sign “B” is allowed to move or linearly reciprocate whereas the one marked with reference sign “A” is blocked because stopper pin 130 is in such a position which prevents the movement of shift rod 106 marked with reference sign A. This means arcuate shaped feature 134 is not in alignment with the position of shift rod 106 marked with reference sign B, thereby blocking its linear movement along direction D.

[0042] In an alternative embodiment, it is possible, as would be derivable, that shift rod 106 characterized with reference sign “B” is blocked whereas shift rod 106 characterized with reference sign “A” is allowed to linearly reciprocate. For this to occur, stopper pin 130 should be made to move along direction M in a pull direction movement such that arcuate shaped feature 134 matches with the shift rod marked with reference sign A to enable the corresponding shift rod’s axial movement.

[0043] It should be noted that the movement of stopper pin 130 is effected by solenoid actuator 110, in particular by the movement of rod 120 in the direction or a parallel orientation to the direction marked with arrow mark “M".

[0044] According to a preferred embodiment, an actuator rod 120 of solenoid actuator 110 is coupled with stopper pin 130 through a coupling element 128 such that the linear movement of actuator rod 120 can be transferred to stopper pin 130. Such a coupling element 128 is shown both in Figs. 2 and 3. Coupling element 128 according to the present embodiment, enables force or work transfer from one end (preferably second end 120.2) of actuator rod 120 of solenoid actuator 110 onto stopper pin 130, despite the fact the diameter of actuator rod 120 of solenoid actuator 110 is relatively smaller than a nominal width of stopper pin 130. As can be derived from Fig. 3, stopper pin 130 can, for instance, have a width that matches with the diameter of coupling element 128. Such a design enables seamless transfer of work from the end of actuator rod 120 of solenoid actuator 110 to stopper pin 130.

[0045] In accordance with this preferred embodiment, it should also be noted that depending on the direction of movement of actuator rod 120 of solenoid actuator 110 i.e. , whether it is “pull” (P1 in Figs. 2 and 3) or “push” (P2 in Figs. 2 and 3) movement along the direction indicated with an arrow mark “M” in Fig. 3, stopper pin 130 moves either towards a solenoid actuator housing 122 or away from it. In order to facilitate the “pull” direction movement of stopper pin 130, stopper pin 130 is connected with coupling element 128 through a coupler 130.3, which, for instance, could be a simple nut. Further details regarding the working of the present invention will be provided at a later section of this description.

[0046] Still furthermore, stopper pin 130 includes a hollow cylinder 130.1 receiving a spring

[0047] 130.2, wherein spring 130.2 extends and applies extension force on stopper pin 130. Spring 130.2 achieves the effect of retaining the position of stopper pin 130 with respect to housing 116.1 of locking mechanism 116. If actuator rod 120 performs the pull function, spring 130 is compressed between the hollow cylinder and a pin or coupler 130.3. If actuator rod 120 performs the push function, spring 130.2 extends between coupler 130.3 and the hollow cylinder of stopper pin 130 such that the desired position of stopper pin 130 is achieved faster.

[0048] In the same or a different preferred embodiment, as can also be derived from Figs. 2 and 3, electronic gearbox control mechanism 100 further comprises a position sensor (marked with reference sign “PS” in Figs. 2 and 3) for assisting in determining the gear that is currently engaged by electronic gearbox control mechanism 100, and wherein position sensor PS receives at least part of inductive signal from a magnet 126. For instance, magnet 126 is associated with solenoid actuator 110 will be explained further below. It is particularly advantageous, that position sensor PS is a magnetically inducible sensor, preferably, a Hall sensor. In a further particularly advantageous embodiment, position sensor PS is a 3D-hall sensor which is configured to take input not only from magnet 126, but also further signal transmitters present in association with electronic gearbox control mechanism 100.

[0049] In accordance with the present invention, as can be taken from Fig. 3, solenoid actuator- based control unit 104 which is adapted for gearbox 50 (see Fig. 1) of commercial vehicle 10 (see Fig. 1). The solenoid actuator-based control unit comprises solenoid actuator 110, which in turn comprises solenoid actuator housing 122, and actuator rod 120 configured to linearly reciprocate at least partially within housing 122, wherein actuator rod 120 comprises a first end 120.1 and a second end

[0050] 120.2. Actuator rod 120 further comprises a magnet holder 124 holding a magnet 126, wherein magnet holder 124 is either coupled to or formed integrally with respect to first end 120.1 of actuator rod 120, and wherein second end 120.2 of actuator rod 120 is arranged opposite to first end 120.1 of actuator rod 120 and preferably, is configured to selectively at least partially extend through an opening 122.1 of housing 122.

[0051] Further, solenoid actuator 110 is a push-pull solenoid actuator configured to reciprocate actuator rod 120 linearly in both a push-direction (see P2 in Figs. 2 and 3) and a pull-direction (see P1 in Figs. 2 and 3), and is configured to at least partially extend actuator rod 120 through opening 122.1 of housing 122 during the pushdirection movement. In order to understand, the push and pull direction movement of actuator rod 120, reference is made to arrow mark “M”. The movement of actuator rod 120 along or parallel to the direction marked with arrow mark “M” towards stopper pin 130 is referred to as the push direction movement whereas the movement of actuator 120 along or parallel to direction marked with arrow mark “M” towards housing is referred to as pull direction movement. In any case, with the help of the explanation above and the reference arrow marks provided along reference sign “M” in Fig. 3, it should be derivable what is meant with the push or pull direction movement. In any case, since solenoid actuator 110 is configured to linearly reciprocate in both the push and pull directions, the selection of one among shift rods 106 marked with reference signs “A” and “B” in Fig. 3 is easily performed with the help of locking mechanism 116 (explained above).

[0052] Still furthermore, solenoid actuator 110 is configured to operate with a solenoid force at 5 - 70 N at 100% Duty Cycle and to operate with a solenoid force of 30- 350N at 5% Duty Cycle. 4. For precise control of actuator rod 120’s movement, solenoid actuator 110 is configured to have a stroke length of 5 - 50 mm. A precision of the order of millimeters is necessary to exactly position arcuate shaped features 132 and 134 aligning with the axial position of shift rods 106 marked with reference signs A and B in Fig. 3.

[0053] In the following paragraphs, a general working principle of electronic gearbox control mechanism 100 of the present invention will be explained.

[0054] When a user or operator of commercial vehicle 10 requests a gearshift, this operation needs to be performed as a set of sequential steps. For instance, if the requested gear is the third gear, the following operations needs to be performed.

[0055] An ECU (not shown in any of the figures) associated with the gearbox control includes a predetermined gear pattern on which of the shift rods labeled as “106” is required to be “shifted” or “linearly” moved to engage the high or low side gear. While it is explained for the sake of understanding of the present invention as the movement of shift rods 106 as linearly, the movement of shift rods 106 can also be arcuate or rotational or angular movement through which further engaging elements such as shift forks can be moved. Furthermore, the direction of movement along or parallel to the direction indicated with arrow mark “D” needs to be determined such as whether to move the corresponding shift rod needs to move forward or backward. Once these steps are performed, the ECU ensures or checks whether the current gear position is in neutral and transmits a control signal to solenoid actuator-based control unit 104 and / or solenoid actuator 110 to perform push or pull direction movement (thereby, moving solenoid actuator- based control unit 104 and / or solenoid actuator 110 select position) along the direction as indicated with an arrow mark “M”. Depending on the direction of the movement i.e,. the push or pull movement, solenoid actuator 110 through its actuator rod 120 places stopper pin 130 at an appropriate position so that either shift rod 106A or 106B can linearly reciprocate or move along the direction or in parallel to the direction indicated with arrow mark “D”. In the present case, for the sake of illustration only and as shown in Fig. 3, shift rod 106B is positioned to align with arcuate shaped feature 132 (a slot or a groove) at housing 116.1 and stopper pin 130 whereas shift rod 106A is blocked from performing any linear movement along or parallel to direction indicated with arrow mark D. This implies, shift rod 106B is not operably connected with housing 116.1 when the shifting operation is performed. As can be seen, stopper pin 130 engages with shift rod 106A such that any shifting operation performed on housing 116.1 will be transferred to shift rod 106A, resulting in only shift rod 106A moving.

[0056] Further, motor-based shift control unit 102 through its motor 112 operates rack-and- pinion mechanism 114 and moves the gear shift finger wich is located inside an operational block 190 (see Figs. 1 and 2) in the direction or parallel to the direction indicated with arrow mark D, either in a forward direction or backward direction. Operational block 190 is in turn operably connected with housing 116.1. Thus, when motor-based shift control unit 102 performs a shifting operation to move housing 116.1 in the direction or along the direction parallel to the one marked with arrow mark “D”, it is transferred also to housing 116.1 and then, in the case shown in Fig. 3, to shift rod 106A in the end. Typically, shift rods of gearshift control mechanisms have at least one shift fork (not shown in figures) attached to the end of the shift rods. The shift forks move coupling mechanisms such as synchronizers (not show in figures) or dog-clutches (not shown in figures) to enable either coupling or decoupling a particular gear.

[0057] In order to fully appreciate the scope of the present invention, the wording of the claims shall be used. For assisting with the understanding the scope of the invention, the description and drawings along with the accompanying claims can be used. List of reference signs (Part of the description)

[0058] 10 - commercial vehicle

[0059] 50 - gearbox or a vehicle power transmission unit

[0060] 100 - electronic gearbox control mechanism

[0061] 102 - motor-based shift control unit

[0062] 104 - solenoid actuator-based control unit 104

[0063] 106 - one or more shift rods

[0064] 106A - one of the one or more shift rods

[0065] 106B - another of the one or more shift rodsl 08 - select rod

[0066] 110 - solenoid actuator

[0067] 112 - electric motor

[0068] 114 - a rack-and-pinion mechanism

[0069] 116 - locking mechanism

[0070] 116.1 - housing of locking mechanism 116.1

[0071] 120 - linearly receiprocating actuator rod of solenoid actuator 110

[0072] 120.1 - first end of linearly receiprocating actuator rod 120

[0073] 120.2 - second end of linearly receiprocating actuator rod 120

[0074] 122 - solenoid actuator housing

[0075] 122.1 - (first) opening of solenoid actuator housin 122

[0076] 124 - magnet holder

[0077] 126 - magnet

[0078] 128 - coupling element

[0079] 130 - stopper pin 130.1 - hollow cylinder

[0080] 130.2 - spring

[0081] 130.3 - a pin or coupler

[0082] 132 - one of arcuate shaped features at stoper pin 130

[0083] 134 - another of arcuate shaped features at stopper pin 130

[0084] 190 - operational block

[0085] D - arrow mark reflecting the direction of movement of rod 106 or its parallel direction

[0086] M - a (two-sided) arrow mark to indicate a direction in which stopper pin 130 moves either towards a solenoid actuator housing 122 or away from it

[0087] P - reference plane upon which or on a parallel plan rods 106 and 108 are perpendicular

[0088] P1 - pull movement indicated at one side of two-sided arrow mark P1-P2 in Figs. 2 and 3 for actuator rod 120 or solenoid actuator 110

[0089] P2 - push movement at one side of two-sided arrow mark P1-P2 in Figs. 2 and 3 for actuator rod 120 or solenoid actuator 110

[0090] IS - input shaft

[0091] OS - output shaft

[0092] PS - position sensor

Claims

Claims1. A solenoid actuator-based control unit (104) adapted for a drivetrain transmission unit or a gearbox (50) of a commercial vehicle (10), comprising a solenoid actuator (110), comprising a housing (122), an actuator rod (120) configured to linearly reciprocate at least partially within the housing (122), wherein the actuator rod (120) comprises a first end (120.1) and a second end (120.2), wherein the actuator rod (120) further comprises a magnet holder (124) holding a magnet (126), wherein the magnet holder (124) is either coupled to or formed integrally with respect to the first end (120.1) of the actuator rod (120), and wherein the second end (120.2) of the actuator rod (120) is arranged opposite to the first end (120.1) of the actuator rod (120) and is configured to either selectively or at least partially extend through an opening (122.1) of the housing (122).

2. The solenoid actuator-based control unit (104) according to claim 1, wherein the solenoid actuator (110) is a push-pull solenoid actuator configured to reciprocate the actuator rod (120) linearly in both a push-direction (P2) and a pull-direction (P1) for select position change, and wherein the solenoid actuator (110) is configured to at least partially extend the actuator rod (120) through the opening (122.1) of the housing (122) during the push-direction movement.

3. The solenoid actuator-based control unit (104) in accordance with any one of the above claims, wherein the solenoid actuator is configured to operate with a solenoid force at 5 - 70 N at 100% Duty Cycle and to operate with a solenoid force of 30- 350N at 5% Duty Cycle.

4. The solenoid actuator-based control unit (104) in accordance with any one of the above claims, wherein the solenoid actuator (110) is configured to have a stroke length of 5 - 50 mm.

5. An electronic gearbox control mechanism (100) for a drive train transmission unit or a gearbox (50) of a commercial vehicle (10), comprising a motor-based shift control unit (102);at least one shift rod (106) configured to move depending on the movement derived from the motor-based shift control unit (102); a select rod (108) arranged perpendicular to the shift rod (106); and the solenoid actuator-based control unit (104) according to any one of claims 1 to 4 connected directly or indirectly with at least the select rod (108), characterized in that, the solenoid actuator (110) facilitates engagement or disengagement between the motor-based shift control unit and the at least one shift rod and controls the movement of the select rod (108) by linearly reciprocating the actuator rod (120).

6. The electronic gearbox control mechanism (100) according to claim 5, wherein the motor-based shift control unit (102) comprises an electric motor (112) and a rack- and-pinion mechanism (114), and wherein the motor-based shift control unit is configured to move the engaged shift rod in a linearly translatory movement when the engagement between the motor-based shift control unit and the engaged shift rod is complete.

7. The electronic gearbox control mechanism (100) according to any one of claims 5 and 6, wherein the electrically activated gearbox control mechanism further comprises a locking mechanism (116) that is controlled by the solenoid actuator (110) for at least two positions, namely engaged or disengaged positions or first and second select positions, depending on which the at least one shift rod (116) is engaged with the motor-based shift control unit (102).

8. The electronic gearbox control mechanism (100) according to claim 7, wherein the locking mechanism (116) comprises a stopper pin (130) with at least two arcuate shaped features (132, 134) and is adapted to move linearly from a first select position to a second select position and vice versa, wherein the gearbox control mechanism (100) has at least two shift rods (106), and wherein at least one of the at least two shift rods (106) can be selectively slidingly received at one of the at least two arcuate shaped features (132), respectively, depending on the latest position of the stopper pin (130).

9. The electronic gearbox control mechanism (100) of claim 8, wherein the actuator rod (102) of the solenoid actuator (110) is coupled with the stopper pin (130) througha coupling element (128) such that the linear movement of the actuator rod (102) can be transferred to the stopper pin (130).

10. The electronic gearbox control mechanism (100) of any one of claims 8 and 9, wherein the stopper pin (130) includes a hollow cylinder (130.1) receiving a spring (130.2), wherein the spring (130.2) extends and applies extension force on the stopper pin (130).

11. The electronic gearbox control mechanism (100) according to any one of the above claims, wherein the electronic gearbox control mechanism further comprises a position sensor (PS) for assisting in determining the gear that is currently engaged by the electronic gearbox control mechanism, and wherein the position sensor (PS) receives at least part of inductive signal from the magnet (126).

12. The electronic gearbox control mechanism according to claim 11, wherein the position sensor (PS) is a magnetically inducible sensor, preferably, a Hall sensor.

13. A gearbox (50) comprising an input shaft (IS) and output shaft (OS), and configured to achieve at least two different speed ratios between the input and output shafts, and comprising the electronic gearbox control mechanism (100) in accordance with any one of claims 5 to 12.

14. The gearbox (50) of claim 13, wherein the gearbox is configured to achieve at least four different speed ratios between the input and output shafts of the gearbox.

15. A commercial vehicle (10) comprising the gearbox in accordance with any one of claims 13 and 14.

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