FIELD OF THE INVENTION

The present disclosure relates to seat suspensions and more particularly relates to a seat positioning system with predefined positions for a seat of a vehicle.

BACKGROUND

Vehicles, more specifically Off-road vehicles such as tractors, forklift trucks, excavators, and the like, are provided with an air spring -supported seat to accommodate vibrations during vehicle operations. Such seats utilize extension or compression of the air springs that support the occupant' s/driver’s weight and absorb all the uneven forces and vibrations while traveling on an uneven surface or lifting a load. However, because the seat occupant's weight and sudden forces are relatively too high that the uneven forces and vibrations lead to the failure of the spring that supports the occupant’s seat. Furthermore, such are uncomfortable due to random adjustments in height of the seat according to the vibrations and load forces.

Advancements were done to improve the comfortability and operating seat suspensions to comfort the occupant/driver while operating. One of the techniques is taught in U.S. Pat. No. 5,618,021 which discloses a seat suspension having a mechanical linkage including at least one linkage arm between a base and a seat, a pneumatic actuator including a valve connected to and moveable with the seat which allows air to be charged to or discharged from the actuator to raise or lower the seat relative to the base. Furthermore, the seat suspension also includes a cam having a roller disposed within an aperture of the cam. However, such a seat suspension is inefficient because prolonged mechanical interaction between the roller and the aperture causes fatigue resulting in wear and tear of the roller and the aperture. Furthermore, the aperture of the cam has grooves at extreme ends that include curved steps to accommodate the roller. Therefore, the roller and the curved steps wear and decrease the durability of the seat suspension. Moreover, the wear and tear of the aperture and/or the roller warrants a change of the entire mechanical linkages and therefore increases the replacement cost. Additionally, the aperture is a closed loop and that limits the span and/or elevation range of the seat suspension. Furthermore, changing the span and/or elevation range of the seat suspension may warrant a change in the design of the cam, and that raises the input cost and increases complexity in accommodation for reinstallation.

Therefore, in light of the foregoing discussions, there is a need to overcome the limitations/drawbacks of the conventional seat suspension of vehicles and more particularly seat suspension of Off-road vehicles.

SUMMARY

This summary is provided to introduce a selection of concepts, in a simplified format, that are further described in the detailed description of the invention. This summary is neither intended to identify key or essential inventive concepts of the invention and nor is it intended for determining the scope of the invention.

The present disclosure relates to a seat positioning system adapted to change a height of a seat frame with respect to a floor. The seat positioning system includes a scissor mechanism adapted to install the seat frame of a seat assembly to the floor. The scissor mechanism includes comprising a first crosslinking member and a second crosslinking member pivotally coupled with each other at their respective centres. Further, the seat positioning system includes an air spring coupled to the first crosslinking member and adapted to facilitate the pivoting of the first crosslinking member and the second crosslinking member. Additionally, the seat positioning module includes an actuation module adapted to operate an air pump fluidly coupled to the air spring and adapted to inflate or deflate air into the air spring. The actuation module includes an upper limit switch defining an upper limit of the pivoting, and a lower limit switch defining a lower limit of the pivoting. Furthermore, the seat positioning system includes a cam securely coupled with the first crosslinking member and adapted to pivot with the first crosslinking member to selectively engage the upper limit switch and the lower limit switch to regulate air supply to the air pump.

Another embodiment of the present disclosure relates to a seat assembly having a seat frame, and a seat positioning system coupled to the seat frame. The seat positioning system of the seat assembly includes a scissor mechanism adapted to install the seat frame of the seat assembly to a floor. The scissor mechanism includes a first crosslinking member and a second crosslinking member pivotally coupled with each other at their respective centres. Additionally, the a seat positioning system includes an air spring coupled to the first crosslinking member and adapted to facilitate the pivoting of the first crosslinking member and the second crosslinking member. In addition, the seat positioning system includes an actuation module adapted to operate an air pump fluidly coupled to the air spring and adapted to inflate or deflate air into the air spring. The actuation module includes an upper limit switch defining an upper limit of the pivoting, and a lower limit switch defining a lower limit of the pivoting. Further, the seat positioning system includes a cam securely coupled with the first crosslinking member and adapted to pivot with the first crosslinking member to selectively engage the upper limit switch and the lower limit switch to regulate air supply to the air pump.

Embodiments of the present disclosure provide an efficient, responsive, robust, and effective seat positioning system that enables a smooth adjustment of the height of the seat as per the requirement of the driver/occupant to enable comfortability to the rider/occupant while in operation.

To further clarify the advantages and features of the present invention, a more particular description of the invention will be rendered by reference to specific embodiments thereof, which is illustrated in the appended drawings. It is appreciated that these drawings depict only typical embodiments of the invention and are therefore not to be considered limiting of its scope. The invention will be described and explained with additional specificity and detail with the accompanying drawings.

BRIEF DESCRIPTION OF THE DRAWINGS

These and other features, aspects, and advantages of the present invention will become better understood when the following detailed description is read with reference to the accompanying drawings in which like characters represent like parts throughout the drawings, wherein:

Figure 1 illustrates a schematic diagram of a seat assembly having a seat positioning system in a lower limit position, according to an embodiment of the present disclosure;

Figure 2 illustrates a schematic diagram of the seat assembly and the seat positioning system in an upper limit position, according to an embodiment of the present disclosure; and

Figure 3 illustrates a circuit diagram of an actuation module, according to an embodiment of the present disclosure.

Further, skilled artisans will appreciate that elements in the drawings are illustrated for simplicity and may not have necessarily been drawn to scale. Furthermore, in terms of the construction of the device, one or more components of the device may have been represented in the drawings by conventional symbols, and the drawings may show only those specific details that are pertinent to understanding the embodiments of the present invention so as not to obscure the drawings with details that will be readily apparent to those of ordinary skill in the art having benefit of the description herein.

DETAILED DESCRIPTION OF FIGURES For the purpose of promoting an understanding of the principles of the invention, reference will now be made to the embodiment illustrated in the drawings and specific language will be used to describe the same. It will nevertheless be understood that no limitation of the scope of the invention is thereby intended, such alterations and further modifications in the illustrated system, and such further applications of the principles of the invention as illustrated therein being contemplated as would normally occur to one skilled in the art to which the invention relates. Unless otherwise defined, all technical and scientific terms used herein have the same meaning as commonly understood by one of the ordinary skilled in the art to which invention belongs. The system and examples provided herein are illustrative only and not intended to be limiting.

For example, the term “some” as used herein may be understood as “none” or “one” or “more than one” or “all.” Therefore, the terms “none,” “one,” “more than one,” “more than one, but not all” or “all” would fall under the definition of “some.” It should be appreciated by a person skilled in the art that the terminology and structure employed herein is for describing, teaching, and illuminating some embodiments and their specific features and elements and therefore, should not be construed to limit, restrict or reduce the spirit and scope of the present disclosure in any way.

For example, any terms used herein, such as, “includes,” “comprises,” “has,” “consists,” and similar grammatical variants do not specify an exact limitation or restriction, and certainly do not exclude the possible addition of one or more features or elements, unless otherwise stated. Further, such terms must not be taken to exclude the possible removal of one or more of the listed features and elements, unless otherwise stated, for example, by using the limiting language, including, but not limited to, “must comprise” or “needs to include.” Whether or not a certain feature or element was limited to being used only once, it may still be referred to as “one or more features” or “one or more elements” or “at least one feature” or “at least one element.” Furthermore, the use of the terms “one or more” or “at least one” feature or element do not preclude there being none of that feature or element, unless otherwise specified by limiting language including, but not limited to, “there needs to be one or more...” or “one or more elements is required.”

Unless otherwise defined, all terms and especially any technical and/or scientific terms, used herein may be taken to have the same meaning as commonly understood by a person ordinarily skilled in the art.

Reference is made herein to some “embodiments.” It should be understood that an embodiment is an example of a possible implementation of any features and/or elements of the present disclosure. Some embodiments have been described for the purpose of explaining one or more of the potential ways in which the specific features and/or elements of the proposed disclosure fulfil the requirements of uniqueness, utility, and non-obviousness.

Use of the phrases and/or terms including, but not limited to, “a first embodiment,” “a further embodiment,” “an alternate embodiment,” “one embodiment,” “an embodiment,” “multiple embodiments,” “some embodiments,” “other embodiments,” “further embodiment”, “furthermore embodiment”, “additional embodiment” or other variants thereof do not necessarily refer to the same embodiments. Unless otherwise specified, one or more particular features and/or elements described in connection with one or more embodiments may be found in one embodiment, or may be found in more than one embodiment, or may be found in all embodiments, or may be found in no embodiments. Although one or more features and/or elements may be described herein in the context of only a single embodiment, or in the context of more than one embodiment, or in the context of all embodiments, the features and/or elements may instead be provided separately or in any appropriate combination or not at all. Conversely, any features and/or elements described in the context of separate embodiments may alternatively be realized as existing together in the context of a single embodiment.

Any particular and all details set forth herein are used in the context of some embodiments and therefore should not necessarily be taken as limiting factors to the proposed disclosure.

Embodiments of the present invention will be described below in detail with reference to the accompanying drawings.

According to an embodiment of the present disclosure, a seat positioning system is disclosed. The seat positioning system is disposed of within a seat of a vehicle. Vehicles such as Off-road vehicles are subjected to uneven forces due to uneven surfaces of ground. The seat suspension is provided to accommodate vibrations from uneven forces, to enable comfort for a rider/occupant thereof. In an embodiment, the seat used herein is a pneumatic suspended seat. The seat positioning system is arranged below the seat of the Off-road vehicles to attenuate the vibrations and enable a comfortable experience for the rider/occupant. As stated herein below the seat positioning system includes an air spring coupled with a pair of cross-linking members to adjust the height of the seat according to the driver/occupant requirement. Moreover, the seat positioning system includes an actuation module to inflate and deflate the air spring to adjust the height of the seat according to the rider/occupant's requirements.

Figures 1 and 2 show a seat assembly 100 having a seat positioning system 102 in different configurations, according to an embodiment of the present disclosure. Specifically, Figure 1 illustrates a schematic diagram of the seat assembly 100 having the seat positioning system 102 in a lower limit position while Figure 2 illustrates a schematic diagram of the seat assembly 100 having the seat positioning system 102 in an upper limit position. The seat positioning system 102 is configured to install the seat assembly 100 on a floor 101. The floor 101, in one example, can be a floor of a vehicle in which the seat assembly 100 is installed. Alternatively, the floor 101 can be the base of the seat positioning system 102. The seat positioning system 102 is designed in such a way that the seat positioning system 102 can either raise the height of the seat assembly 100 as shown in Figure 2 or lower the height of the seat assembly 100 as shown in Figure 1. The seat positioning system 102 may include, but is not limited to, a scissor mechanism 104, an air spring 106, an actuation module 108, an air pump 110, and a release valve 112. Details of each of such components will be explained later.

Throughout the present disclosure, the “seat positioning system” as used herein refers to height adjustment mechanisms in seat suspensions of vehicles and is adapted to adjust the height of the seat to enable comfortability to the driver/occupant while in operation. The seat positioning system 102 is configured to adjust the height as per the requirement of the driver/occupant. In an example, the seat positioning system 102 is also configured to adjust the height of the seat to the predefined height positions to avoid bottoming/top out of the seat. The seat positioning system 102 also enables the adjustment of the height of the seat to the driver/occupant comfort position in between the predefined position.

In one example, the scissor mechanism 104 may be adapted to couple a seat frame 103 of the seat assembly 100 to the floor 101. Further, the scissor mechanism 104 includes a first crosslinking member 140, and a second crosslinking member 142 pivotally coupled with the first crosslinking member 140 at their respective centres. Further, each of the first crosslinking member 140 and the second crosslinking member 142 may include a first end 144 adapted to pivotally couple with the frame 103. In addition, Further, each of the first crosslinking member 140 and the second crosslinking member 142 may include a second end 146 disposed of opposite to the first end 144 pivotally coupled with a bottom side of the seat frame 103. The first end 144 and the second end 146 of both the crosslinking members may be attached to the frame 103 by hinges (not shown). Further, each of the first crosslinking member 140 and the second crosslinking member 142 may include a middle portion 148 extending between the first end 144 and the second end 146 of the first crosslinking member 140. The middle portion 148 of the first crosslinking member 140 facilitates the pivotal coupling of the first crosslinking member 140 with the second crosslinking member 142. In one example, the first crosslinking member 140 is coupled to the second crosslinking member 142 and are pivotably coupled at their respective centers forming a joint. The pivotal coupling of the first crosslinking member 140 with the second crosslinking member 142 facilitates the rising and lowering of the second ends 146 of the pair crosslinking members 140, 142.

In one embodiment, the pair of crosslinking members 140, 142 coupled to the seat of the vehicle. The pair of crosslinking members 140, 142 forms the scissor mechanism 104 provided at a base of the seat of the vehicle and adapted to assume an increase and/or decrease in elevation to adjust the height of the seat as per the requirement of the driver/occupant to enable comfortability to the driver/occupant while in operation. The pair of crosslinking members 140, 142 are provided with notches at one end to the couple at a base of the seat of the vehicle. In an example, each of the pair of crosslinking members 140, 142 is pivotably attached to the base of the seat while each of the pair of crosslinking members 140, 142 are pivotably connected at the center and thereby forming the scissor mechanism. In another example, one of the pair of crosslinking members 140, 142 is fixed to the base of the seat. Furthermore, a movement of the pair of crosslinking members 140, 142 assumes an increase and decrease in elevation of the pair of crosslinking members 140, 142 to change the height of the seat as per the requirement of the driver/occupant.

In one example, the air spring 106 is configured to pivot the first crosslinking member 140 with respect to the second crosslinking member 142. Specifically, the air spring 106 is attached to one of crosslinking members 140, 142 to enable a swinging movement of the pair of crosslinking members 140, 142 to assume an increase and decrease in elevation of the pair of crosslinking members 140, 142 to enable change in the height of seat frame 103. The air spring 106 can be a bellow that can inflate or deflate, such that the inflation or deflation exerts a force on the first crosslinking member 140 which pivots the first crosslinking member 140. The use of air spring 106 enables a quieter operation and does not warrant complex mechanisms, such as electric motors. Moreover, the use of the air spring 106 enables precise control of height adjustment.

In one example, the air pump 110 is fluidically coupled to the air spring 106 and adapted to inflate the air spring 106. The air pump 110 may be installed proximate to the air spring 106 and designed in such a way that the air pump 110 is quieter in operation. The air pump 110 can be a screw type or centrifugal type pump to inflate the air spring 106. On the other hand, the release valve 112 is configured to deflate the air spring 106. The release valve 112 may be a pneumatic release valve that may be coupled to a release port (not shown) to remove air from the air spring 106.

According to the present disclosure, the actuation module 108 may be configured to operate the air pump 110 and the release valve 112 to inflate and deflate the air spring 106. In an example, the air pump 110 is fluidly coupled to the air spring 106 and adapted to inflate or deflate air into the air spring 106. Consequently, the actuation module 108 is configured to cause the pivoting of the scissor mechanism 104 to change the height of the seat frame 103. Details of the actuation module 108 will now be provided with respect to Figure 3 in conjunction with Figures 1 and 2.

Specifically, Figure 3 illustrates a circuit diagram of the actuation module 108, according to an embodiment of the present disclosure. The actuation module 108 is adapted to adjust the elevation of the seat when actuated. The actuation module 108 refers to an electronic circuit and/or a printed circuit board that facilitate a releasing and actuation of the height adjustment when operated by the driver/occupant. The actuation module 108 is a circuit configured to operate based on instructions provided by the driver/occupant. Furthermore, the actuation module 108 is connected to a power source i.e., a battery source to supply power to the circuit.

The actuation module 108 includes a relay key 114, an upper limit switch 116 defining an upper limit of the pivoting, a lower limit switch 118 defining a lower limit of the pivoting, and a push button 120. In addition, the actuation module 108 includes a first relay switch 122 adapted to supply electric power to the air pump 110, and a second relay switch 124 adapted to supply electric power to the release valve 112. In an example, the second relay switch 124 is mounted on a printed circuit board 126, and a power connector 132.

The upper limit switch 116 as used herein relates to switching to a maximum height of the seat respectively. The upper limit switch 116 restricts and closes the adjustment of height at a maximum limit of the seat. On the other hand, the lower limit switch 118 is switching the power through relay key 114 to air pump 110 and the air pump 110 gives air supply to the air spring 106 that lifts the seats to the predefined position to avoid bottoming out. Hence the driver/occupant uses the seat efficiently in a comfortable position. Furthermore, the upper limit switch 116 and the lower limit switch 118 define an elevation range of the seat positioning system 102. Moreover, an angular distance between the upper limit switch 116 and the lower limit switch 118 determines the flexing and restoration of the pair of crosslinking members 140, 142 that defines the range of increase and/or decrease in the height of the seat. In one example, the upper limit switch 116 may define an upper limit of the pivoting and the lower limit switch 118 may define a lower limit of the pivoting.

The push button 120 closes the circuit and triggers the relay key 114 to start the air pump 110 that inflates the air spring 106. The push button 120 is connected to the first relay switch 122 mounted on the printed circuit board assembly that connects the relay key 114. Further, the printed circuit board 126 may draw power from a source connected to the power connector 132. On pressing the push button 120, the first relay switch 122 closes the circuit and the air pump 110 inflates the air spring 106. The inflation of the air spring 106 enables a change in the volume of the air spring 106 that enables a swinging movement of the pair of crosslinking members 140, 142 to assume an increase in elevation of the pair of crosslinking members 140, 142 to enable lifting of the seat.

Furthermore, the air spring 106 is attached to pneumatic release valve 112 that opens to release air from the air spring 106 upon actuation. The push button 120 is also connected to the second relay switch 124 mounted on the printed circuit board assembly that connects the relay key 114. On releasing the push button 120, the second relay switch 124 closes the circuit thereby supplying the electric power to the pneumatic release valve 112 and consequently, the pneumatic release valve 112 deflates the air spring 106. Subsequently, when the pneumatic release valve 112 is open, the air spring 106 deflates and reduces the volume of the air spring 106 which decreases the elevation of the pair of crosslinking members 140, 142 to enable the lowering of the seat.

The cam 130 is disposed within the center of one of the pair of crosslinking members 140, 142. The cam 130 is rotatably coupled to a pivot of the center of the crosslinking members 140, 142. The cam 130 is adapted to oscillate within the circumference of the middle portion 148 of the crosslinking members 140, 142. In an example, the cam 130 is securely coupled with the first crosslinking member 140 and adapted to pivot with the first crosslinking member 140 to selectively engage the upper limit switch 116 and the lower limit switch 118 to regulate air supply to the air pump 110.

Further, the upper limit switch 116 and the lower limit switch 118 include the activation pin 128 which is adapted to be pressed upon contacting/engaging with the cam 130 to open and close the circuit of the actuation module 108. Furthermore, the lower limit switch 118 and the upper limit switch 116 are located at an angular distance and the cam 130 slides to achieve an increase in the elevation and restores to lower the elevation of the seat. Moreover, the location of the lower limit switch 118 and the upper limit switch 116 at the circumference of the cam 130 defines the elevation range of the seat positioning system 102.

According to an embodiment, the driver/occupant presses the push button 120 which triggers the relay key 114. The relay key 114 actuates the air pump 110 to inflate the air spring 106. The inflation of the air spring 106 lifts the pair of crosslinking members 140, 142 and thereby raises the seat. The cam 130 starts oscillating from a rest position towards the upper limit position. In an embodiment, the cam 130 may hold the seat to a halfway position by maintaining the push button 120 at a mid-level position to hold the seat positioning system 102 at a halfway position. For example, the push button 120 may include resting positions to hold the seat positioning system 102 at the halfway position. Furthermore, continuing pressing the push button 120 enables the air spring 106 to lift the pair of crosslinking members 140, 142 to a maximum position and clicks the activation pin 128 of the upper limit switch 116 via the cam 130. The seat positioning system 102 seat holds the seat to the maximum elevation position, and the push button 120 is operated by the driver/occupant.

On releasing the push button 120, the seat positioning system 102 opens the pneumatic release valve 112 that egresses the air from the air spring 106 thereby deflating the air spring 106 and the cam 130 starts oscillating towards the lower limit switch 118. Subsequently, the pair of crosslinking members 140, 142 assumes an increase in elevation, and the cam 130 moves towards the lower limit switch 118. On releasing the air from the air spring 106 and moving towards the lower position, the driver/occupant may continue to hold the push button 120 to a mid-way position to hold the seat positioning system 102 at a halfway position. Furthermore, on continuing the releasing the push button 120 enables the air spring 106 to decrease the elevation of the pair of crosslinking members 140, 142 to a lower position and clicks the activation pin 128 of the lower limit switch 118 via the cam 130. In an example, the occupant touches one time the push button 120 and the circuit will shift to the lower limit switch 118 through relay key 114 will on the air pump 110 to give air to the air spring 106 and lift the seats to the predefined position.

In accordance with the above embodiments, the seat positioning system 102 facilitates a smooth transition from a lower position of the seat to a maximum limit of the seat and vice-versa. According to the requirement of the driver/occupant, the seat positioning system 102 is operable to hold the seat at a desired height and avoids any sudden shift, jerk, bumps experienced by the driver/occupant during the operation. The seat positioning system 100 prevents any bottoming/top out of the seat and enables cushioning of the user/rider/driver in case of any jerk or bump. In addition, the jerks/bumps are absorbed by the cushioning of the seat positioning system 100. In an exemplary analysis, the upper limit will be 130 mm and lower limit will be 50 mm thereby enabling a 50 mm cushioning at top and at bottom position of the seat positioning system. The cam 130 enables the smooth transitioning from a lower position of the seat to a maximum limit of the seat by oscillating between the positions and switching as per instructions of the driver/occupant. In addition, the motion of the seat is jerk free and enables the position of the seat positioning system 102 in the plurality of vertical orientations of height.

While specific language has been used to describe the present disclosure, any limitations arising on account thereto, are not intended. As would be apparent to a person in the art, various working modifications may be made to the method to implement the inventive concept as taught herein. The drawings and the foregoing description give examples of embodiments. Those skilled in the art will appreciate that one or more of the described elements may well be combined into a single functional element. Alternatively, certain elements may be split into multiple functional elements. Elements from one embodiment may be added to another embodiment.