FIELD OF THE INVENTION
The present invention relates to a kinematic linkage assembly for providing improved diagnostics on active aerodynamic vehicle systems such as an active grille shutter assembly.
BACKGROUND OF THE INVENTION
Current Active Grille Shutters (AGS) do not provide adequate monitoring capability if components are damaged or missing. Aerodynamic performance may be degraded without knowledge by the driver. As such devices currently on the market may not be On Board Diagnostic (OBD-2) compliant because the OBD-2 system is not able to tell if the active grille shutter system is working properly or not. It is a goal in the art in the present invention to design an improved linkage, which uses a kinematic linkage design that allows vehicle control systems to accurately detect broken or missing components of the active grille shutter system using on board diagnostic detection.
Typical AGS assemblies have vanes that move between an open and closed position using a series of connected links, controlled by an actuator. The linkage is generally a single piece connecting all the vanes together. Due to the use of a single component, if some of the vanes are missing, the actuator cannot sense a difference, and a damaged assembly can go unnoticed. By making the linkage a series of geared vane connections it is possible to eliminate the one piece linkage and provide a way for the on-board diagnostics of the vehicle to detect a missing or damaged AGS, which is sensed by over rotation of the gears.
Further areas of applicability of the present invention will become apparent from the detailed description provided hereinafter. The detailed description and specific examples, while indicating the preferred embodiment of the invention, are intended for purposes of illustration only and are not intended to limit the scope of the invention.
BRIEF DESCRIPTION OF THE DRAWINGS
The present invention will become more fully understood from the detailed description and the accompanying drawings, wherein:
FIG. 1 is an enlarged side elevational view of a kinematic end cap.
FIG. 2 is a side perspective view of a kinematic end cap with vanes connected in the open position according to one embodiment of the invention.
FIG. 3 is a side perspective view of a kinematic end cap with vanes connected in the closed position according to one embodiment of the invention.
FIG. 4A is a side elevational view of an end cap with the top vane missing.
FIG. 4B is a side elevational view of the end cap with the top vane missing.
FIG. 5A is a side elevational view of an end cap with the bottom vane missing.
FIG. 5B is a side elevational view of an end cap with the bottom vane missing.
FIG. 5C is a side elevational view of an end cap with the bottom vane missing.
FIG. 6A is an enlarged perspective view of the drive gear with drive vane connected.
FIG. 6B is an enlarged perspective view of the drive gear with the drive vane missing.
FIG. 7A is a side perspective view of the formation of the kinematic end cap.
FIG. 7B is a side perspective view of the formation of the kinematic end cap.
FIG. 7C is a side perspective view of the formation of the kinematic end cap.
FIG. 8A is a side elevational view of the kinematic end cap with the drive gear and driven gears in the forming position.
FIG. 8B is a side elevational view of the kinematic end cap with the drive gear and driven gears in the first rotationally engaged position.
FIG. 8A is a side elevational view of the kinematic end cap with the drive gear and driven gears in the second rotationally engaged position.
FIG. 9A is a side elevational view of a kinematic linkage assembly in the open position.
FIG. 9B is a side elevational view of a kinematic linkage assembly in the closed position.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS
The following description of the preferred embodiments are merely exemplary in nature and is in no way intended to limit the invention, its application, or uses.
Referring now to the figures, with particular reference to FIGS. 9A and 9B a kinematic linkage assembly 10 for an active grille shutter system according to a first embodiment of the invention is shown. The kinematic linkage assembly 10 has a frame 12 having formed an aperture 14, wherein the frame 12 is connectable to a vehicle engine compartment and has a kinematic end cap 16 and an end cap 18 at opposing sides of the aperture 14.
While a single kinematic end cap 16 and end cap 18 are shown with three vanes it is within the scope of the invention for the kinematic linkage assembly 10 to have a greater number of kinematic end caps, end caps and vanes depending on the desired size of the kinematic linkage assembly. In some embodiments the kinematic linkage assembly is modular and the kinematic end cap and end cap each have connecting features that allows them to be connected together or stacked to form kinematic linkage assemblies of greater heights. Also, the vanes can be formed from extrusion allowing the vanes to have any type of length depending on the needs of a particular application. An example of the connecting features between end caps and the extruded vanes is described in U.S. Pat. No. 10,960,754, issued Mar. 30, 2021, titled “MOLD ASSEMBLY FOR ACTIVE GRILLE SHUTTER SYSTEM” to Lindberg et al, the entire patent is hereby expressly incorporated by reference.
Referring now to all the figures, the kinematic linkage assembly 10 includes a drive vane 20 and a plurality of driven vanes 22a, 22b, 22c, wherein the drive vane 20 has a first end 24 and the plurality of driven vanes 22a, 22b, 22c each have a first end 26a, 26b, 26c each connected to the kinematic end cap 16. The drive vane 20 has a second end 25 and the plurality of driven vanes 22a, 22b, 22c each have a second end 27a, 27b, 27c, all of which are rotatably connected respectively to a rotatable holder 29a, 29b, 29c, 29d connected to the end cap 18. During operation of the kinematic linkage assembly 10 the drive vane 20 and the plurality of driven vanes 22a, 22b, 22c are each moveable between an open position (shown in FIG. 2) and a closed position (shown in FIG. 3). In the embodiment shown in FIGS. 2 and 3 there is an open end stop 28 that driven vane 22a comes into contact with to prevent over rotation of the kinematic linkage assembly 10, while the driven vane 22b contacts a closed end stop 30 when the drive vane 20 and driven vanes 22a, 22b, 22c are rotated to the closed position. When the drive vane 20 and the driven vanes 22a, 22b, 22c are in the closed position air is prevented from moving through the aperture 14 of the frame 12. When the drive vane 20 and the driven vanes 22a, 22b, 22c are in the open position, air moves through the aperture 14 of the frame 12.
The kinematic linkage assembly 10 further includes a drive gear 32 rotatably connected to the kinematic end cap 16. The drive gear 32 has a portion 34 connected to an actuator 35 by a shaft that extends through the kinematic end cap 16 and engages the actuator 35 that is able to rotate the shaft bidirectionally depending on the desired position of the drive vane 20 and driven vanes 22a, 22b, 22c. The drive gear 32 further includes a gear portion 38 circumscribing the drive portion 34 and includes a plurality of teeth 40 on the outer circumference of the gear portion 38. The gear portion 38 has teeth that are in mesh engagement with teeth 44 formed on a first driven gear 33a and teeth 48 formed on the second driven gear 33b. The drive portion 34 has at least one pair of vane engagement fingers 36a, 36b and the gear portion 38 includes at least one pair of vane engagement tabs 42a, 42b, both of which are configured to connect to the first end 24 of the drive vane 20.
Referring now to FIGS. 2, 3, 6A, 6B, 9 and 10 when the first end 24 of the drive vane 20 is held by both the vane engagement fingers 36a, 36b and vane engagement tabs 42a, 42b, the gear portion 38 and the drive portion 34 rotate together; as rotational force from the actuator 35 is transferred from the actuator 35 to the driven portion 34 and transferred through the first end 24 of the drive vane and onto the gear portion 38. If the first end 24 of the vane 20 is not held by both the vane engagement fingers 36a, 36b and vane engagement tabs 42a, 42b, such as when the drive vane 20 is broken or missing, the drive portion 34 will rotate independently of the gear portion and there will be no rotational force transfer from the drive portion 34 to the gear portion 38, as shown in FIG. 6B. Subsequently rotational force will not be transferred from the actuator 35 to the first driven gear 33a and the second driven gear 33b that are located adjacent the drive gear 32.
The first driven gear 33a has at least one pair of vane engagement fingers 45a, 45b configured to connect to the first end 26a of the driven vane 26a. The plurality of teeth 44 on the outer circumference of the first driven gear 33a are in mesh engagement with the plurality of teeth 40 of the gear portion 38 of the drive gear 32 so that rotation of the drive gear 32 causes rotation of the first driven gear 33a. The second driven gear 33b has at least one pair of vane engagement fingers 46a, 46b configured to connect to the first end 26b of a second one of the plurality of driven vanes 22b. The second driven gear 33b also includes the plurality of teeth 48 on the outer circumference of the second driven gear 33b that are in mesh engagement with the plurality of teeth 40 of the drive gear 32 so that rotation of the drive gear 32 causes rotation of the second driven gear 33b.
Referring also to FIGS. 4A and 4B the rotation of the kinematic linkage assembly 10 when the driven vane 22a (i.e., the upper vane relative to the driven vane 20) is broken or missing. The drive vane 20 is rotated in the direction of the arrow shown in FIG. 4A and will rotate without the driven vane 22a being present. However, an error code will be generated by sensors in the actuator due to differential rotation of the drive gear 32 causing over rotation of the drive vane 20. Also, an optional safety stop 50 (shown schematically) can be positioned on the kinematic assembly or somewhere on the frame 12 to arrest travel of the drive vane 20 to prevent it from travelling too far and re-closing the aperture 14.
Referring also to FIGS. 5A, 5B and 5C the rotation of the kinematic linkage assembly 10 when the driven vane 22b (i.e., the lower vane relative to the driven vane 20) is broken or missing. The drive vane 20 is rotated in the direction of the arrow shown in FIG. 5B and will rotate without the driven vane 22b being present. However, an error code will be generated by sensors in the actuator due to differential rotation of the drive gear 32 causing over rotation of the drive vane 20. Also, an optional safety stop 52 (shown schematically) can be positioned on the kinematic assembly or somewhere on the frame 12 to arrest travel of the drive vane 20 to prevent it from travelling too far and re-closing the aperture 14.
Referring now to FIGS. 7A, 7B and 7C a method of forming the kinematic end cap 16 with the drive gear 32 and driven gears 33a, 33b is shown. The method involves three steps. As shown in FIG. 7A the kinematic end cap 16 is formed by a first molding step. During a second molding step, shown in FIG. 7B the driven gears 33a, 33b and gear portion 38 of the drive gear 32 are all formed. Lastly during a third molding step, shown in FIG. 7C the drive portion 34 is separately molded into the aperture of the gear portion 38. This allows for the drive portion 34 to be rotatable within the gear portion. Referring now to FIGS. 8A, 8B and 8c formation of the drive gear 32 and driven gears 33a, 33b on the kinematic end cap 16 is now described in view of the tooling considerations and requirements. One problem is that the drive gear 32 and driven gears 33a, 33b must be molded in a way that they will be formed separately so they do not stick together, yet in operation they must be able to come into contact. To address this problem the gear portion 38 of the drive gear 32 has small teeth 52a, 52b, 52c, 52d, driven gear 33a has two small teeth 54a, 54b and driven gear 33b has two small teeth 56a, 56b. In FIG. 8A the drive gear 32, driven gear 33a and driven gear 22b are all in the molding position and are formed so that the small teeth 52a, 52b of drive gear 32 are adjacent small teeth 54a, 54b of the driven gear 33a and will not touch. Likewise small teeth 52c, 52c of drive gear 32 are adjacent small teeth 56a, 56b of the driven gear 33b are formed and will not touch. Then as shown in FIG. 8B the drive gear 32 and driven gears 33a, 33b are rotated so that the larger teeth are in engagement when the kinematic linkage assembly 10 is in the fully open position. Likewise in FIG. 8C the drive gear 32 and driven gears 33a, 33b are rotated so that the larger teeth are in engagement when the kinematic linkage assembly 10 is in the fully closed position. While six small teeth are shown, it is within the scope of the invention for there to be a greater or lesser number of small teeth on the drive gear 32 and driven gears 33a, 33b depending on the needs of a particular application, which include the size, configuration and number of gears.
The description of the invention is merely exemplary in nature and, thus, variations that do not depart from the gist of the invention are intended to be within the scope of the invention. Such variations are not to be regarded as a departure from the spirit and scope of the invention.