Interchangable lever assemblies

A lever assembly. The assembly may include a lever, a shaft coupled to the lever for supporting pivotal movement of the lever, a magnet coupled to the lever, the magnet being configured to rotate upon pivotal movement of the lever, and magnetic field sensor positioned adjacent the magnet for providing an output representative to position of the lever.

TECHNICAL FIELD

This disclosure relates to lever assemblies configured for controlling system functionality, and in particular to lever assemblies that may be interchangeable.

BACKGROUND

Lever assemblies may be used for controlling functions in a variety of systems. For example, several lever assemblies may be used to control different associated functions on a forklift or other vehicle.

Although the following Detailed Description will proceed with reference being made to illustrative embodiments, many alternatives, modifications, and variations thereof will be apparent to those skilled in the art. Accordingly, it is intended that the claimed subject matter be viewed broadly.

DETAILED DESCRIPTION

The description provided herein is with reference to various exemplary embodiments. It is to be understood that the embodiments described herein are presented by way of illustration, not of limitation. Also, the embodiments may be described herein with respect to a forklift application. The present invention may be incorporated into a wide variety of systems without departing from the spirit and scope of the invention. In general, a system and method consistent with the present disclosure may involve providing lever assemblies with “plug and play” capability within a desired application. Features of the lever assemblies and mating portions, combined with identification magnets, allow facile removal and replacement of the lever assemblies. When the lever assemblies are installed in associated mating portions, they may be automatically recognized and identified by an associated module positioned in the mating portion and below the lever assembly. Assembly errors, e.g. assembly of an incorrect lever assembly into a mating portion may also be automatically detected. This recognition, identification and/or error identification may be accomplished without use of a direct electrical connection.

Turning toFIG. 1, there is shown an exemplary arm rest assembly100including a plurality of lever assemblies102-1,102-2,102-3coupled to an associated system, e.g. a construction vehicle armrest100, consistent with the present disclosure. As shown the lever assemblies may be mounted on top surface of the assembly100. As will be described in greater detail below, an associated printed circuit board (PCB) module assembly may be located within the armrest. The lever assemblies may cooperate with sensors, e.g. magnetic field sensors such as Hall Effect devices, and electronics on the PCB assembly to control functionality of a system, such as a forklift or other construction vehicle, and to provide recognition, identification and/or error identification related to the lever assemblies. As illustrated inFIG. 2, in one embodiment each lever assembly102may include a lever202pivotable through a range of about +/−25° from a centerline206of the lever202in an at-rest position.

FIG. 2illustrates an exemplary lever assembly102in bottom perspective view. As shown, the lever202may be pivot about pivot shaft302for causing corresponding movement of a pivot arm, e.g. against the bias of a torsion spring304. Movement of the lever202, e.g. by an operator, may cause corresponding movement of the pivot arm200. When the assembly102is mounted in an associated mating portion306, e.g. in a top surface of an assembly100, the pivot arm200may extend through an opening308in the mating portion for rotating or otherwise moving one or more magnets310associated with the PCB assembly312. As shown inFIG. 4, for example, the pivot arm may200extend through the opening206to engage a magnet carrier400for causing rotational movement of the magnet carrier400and a magnet carried thereby upon movement of the lever202.FIG. 5Ais a bottom view of the magnet carrier400showing the magnet310carried thereby, andFIG. 5Bis a top view of the magnet carrier400. As shown, the magnet carrier may include a channel502for receiving the pivot arm. The channel may be configured to engage the pivot arm during motion thereof to cause rotation of the magnet carrier and the magnet carried thereby.

FIG. 6diagrammatically illustrates rotation of a magnet300adjacent an associated Hall effect device600, e.g. a known tri-axis Hall Effect device. Rotation of the magnet310may be sensed by the Hall Effect device and an output representing lever position may be provided from the Hall Effect device600to a control system for controlling system functionality.

As shown inFIG. 7and also in the sectional view ofFIG. 3, lever assembly102may also or alternatively include a push rod700including a push magnet702coupled thereto. The push rod may be coupled to the lever202for linear movement corresponding to linear movement of the lever, i.e. up/down movement of the lever. Depressing of the lever202may cause the push rod to extend outward from the lever assembly102to place the push magnet702in proximity to a Hall Effect device. When the lever is depressed, the Hall Effect Device may sense the magnet702to actuate an associated feature of the system. When the lever is released, the push rod700may retract into the assembly (e.g. to the position shown inFIG. 3) and the Hall Effect device may indicate that the push magnet is no longer present.

An exemplary PCB module assembly800consistent with the present disclosure is illustrated inFIGS. 8 and 9. As shown in the exploded views ofFIG. 9, the assembly800may include a magnet rotor cover900, magnet carriers/rotors400, torsion springs904, magnetic shields906, a module housing908, a PCB312and a back cover912. A direct connection to the electronics on the PCB312, e.g. via conductive pins coupled to the electronics and extending into an integral connector interface916, may be incorporated into the back cover912for providing input/output to the electronics on the PCB312.

As shown the shields1406may be annular metallic shields for shielding field associated with magnets310in the magnet carriers/rotors300, thereby preventing such fields from effecting output of other sensors in the system and preventing other magnets in the system from affecting the output of the Hall device600used for sensing lever202positions. Likewise, as shown inFIGS. 7 and 10, a steel shunt1000may be used to shunt out fields associated with a push magnet702when the push rod700is an extended position.FIG. 11illustrates an alternative shielding arrangement including a shield1000aand a ring shield906for shunting fields from associated magnets310and702, respectively.

FIGS. 12 and 13illustrate another embodiment of a lever assembly102a, including a lever202, fasteners, e.g. plastic thread forming screws1202, a lever cover1204, a pivot shaft1206, lever torsion springs1028, lever bushings1210, a face gear1212, a lever base1214, a lever pinion1216, a bottom cover1218, and at least one identification magnet1224received in an associated pocket1223. The pivot shaft1206may be pivotally supported between the cover1204and base1214by the bushings for allowing rotation of the shaft relative to the base and cover. The lever202may be coupled to the pivot shaft1206for causing rotation of the pivot shaft1206and the face gear1212coupled thereto upon rotation of the lever in fore and aft directions, e.g. against the bias of the torsion springs1208. The pinion1216and face gear1212are more particularly shown inFIGS. 14 and 15, respectively. As shown inFIG. 16, the face gear11212may meshingly engage the pinion1216to cause rotation of the pinion gear1216about an axis1220that is substantially perpendicular to an axis of rotation1222of the pivot shaft1206. In one embodiment, for example, a +/−25° motion of the lever is converted to rotation that is 90° (perpendicular) from the lever rotation using a gear ratio of 2.33 to 1 to magnify the lever resolution.

As shown inFIGS. 17A and 17B, lever assembly102amay also or alternatively include a push rod1700including a push magnet702coupled thereto. The push rod may be coupled to the lever202for linear movement corresponding to linear movement of the lever, i.e. up/down movement of the lever. In the illustrated exemplary embodiment, the lever is biased to an outward position shown inFIG. 17Aby a compression spring1702and includes an extension extending from an inner surface thereof. A bottom of the extension carries a magnet1706. A second magnet is disposed between arms of the extension and between the inner surface of the lever202and the magnet1706. The magnets1706and1708may be positioned in opposed facing relationship, as shown, to provide a magnetic detent resulting from magnetic attraction. Depressing of the lever202to overcome the attraction between the magnets1706and1708and against the bias of the compression spring may cause the push rod1700to extend outward from the lever assembly102ato place the push magnet702in proximity to a Hall Effect device. When the lever is depressed, as shown inFIG. 17B, the Hall Effect Device may sense the magnet702to actuate an associated feature of the system. When the lever is released, the push rod1700may retract into the assembly, e.g. due to the bias of the spring1702, and may be detented by the attraction between the magnets1706and1708. When the push rod is retracted into the assembly, as shown inFIG. 17A, the Hall Effect device may indicate that the push magnet is no longer present.

An exemplary PCB module assembly1800useful in connection with the lever assembly102aconsistent with the present disclosure is illustrated inFIG. 18. As shown the assembly1800may include a magnet rotor cover900a, magnet carriers/rotors400a, rotor covers1800, magnetic shields906a, a PCB312and a back cover912a. A direct connection to the electronics on the PCB312, e.g. via conductive pins coupled to the electronics and extending into an integral connector interface, may be incorporated into the back cover912afor providing input/output to the electronics on the PCB312.

As shown inFIGS. 19A and 19Bthe magnet rotors400amay include a tab1902extending from a top surface thereof1904, and a magnet310coupled thereto, e.g. adjacent a bottom surface1906thereof. As shown inFIGS. 13 and 14, the pinion gear1216may include a slot in the bottom thereof. The slot may be sized and dimensioned to closely receive the tab portion of a magnet rotor, whereby rotation of the pinion corresponding to pivotal movement of the lever202causes corresponding rotation of the magnet rotor400aand the magnet310coupled thereto, e.g. against the bias of a torsion spring1310(FIG. 13). A Hall Effect device disposed below the magnet310may provide an output indicative of the position of the lever arm202.

Other mechanisms for moving a magnet carrier/rotor with associated movement of a lever may be implemented consistent with the present disclosure. As shown inFIG. 20, for example, the pinion gear may be coupled to the magnet carrier by a shaped peg extending from the top of the magnet rotor that may be received in a corresponding shaped pocket2002in a pinion gear1216a.

FIGS. 21 and 22illustrate relative orientation of rotary magnets310and their associated Hall devices600and shields906,906a, push magnets702and their associated Hall devices2100, and identification (ID) magnets1224and their associated Hall Effect devices2102. The illustrated exemplary embodiment includes 4 rotary magnets310, 4 push magnets702and 8 ID magnets, and may use 12 digital Hall devices and 4 programmable linear Hall devices.

FIG. 26illustrates exemplary mating portions306associated with exemplary lever assemblies102, andFIG. 27illustrates exemplary mating portions306aassociated with exemplary lever assemblies102a. As shown, the mating portions include exemplary keying features2302. In the illustrated exemplary embodiment, the features2302include combinations of different geometric mating receptacles2304,2306. In the illustrated exemplary embodiment, generally square receptacles2306and generally triangular receptacles2304are provided, although the receptacles may be of any geometric shape. The receptacles may be sized and positioned to mate with mating pegs on the bottom surfaces of the associated lever assemblies102,102a.FIG. 25, for example, is a bottom view of a lever assembly102aillustrating mating pegs2504to be received within corresponding mating features2304,2306.

FIGS. 26A-Dillustrate bottom views of various lever assemblies102,102awith features not common to the assemblies not shown for ease of explanation. The square receptacles2306may be sized and positioned to receive square2506or triangular2504mating pegs on associated lever assemblies102,102a, whereas the triangular receptacles2304may receive only triangular mating pegs2504(not the square mating pegs2506). This provides a keying system whereby only lever assemblies102,102ahaving appropriate mating peg configurations may be inserted into an associated mating portion306,306a. This feature may be used to prevent mounting of certain lever assemblies102,102ainto certain mating portions306,306a.

As shown inFIGS. 26A-D, the lever assemblies may also include one or more associated ID magnets1224mounted thereto in different combinations, e.g. in associated pockets. The ID magnets1224may be positioned in opposed relationship to associated ID Hall devices2102, as shown inFIGS. 21 and 22. The digital Hall devices2102may react to the magnets1224when the magnets are in close proximity. The respective outputs of the Hall devices2102may be provide data on a vehicle bus, e.g. a CAN bus, indicating status and presence, of the lever assemblies, without requiring a direct electrical connection between the lever assembly and the PCB. Table 1 below, for example, is one embodiment of a matrix illustrating the data (“CAN data” in Table 1) resulting from the Hall device2101outputs where the Hall devices are numbered (“Hall #” in Table 1) according to the correspondingly numbered locations inFIG. 27, along with the corresponding diagnostic conditions and CAN message and data location:

If no lever assembly is present, the Hall devices2102will not react, thereby facilitating detection of lever presence. Error detection may also be accomplished by comparing the output of the Hall devices2102with the remaining hall devices. In one embodiment, lever assemblies may differ in their height, color, part number, how the push function is engaged if at all, etc. If, for example, a standard lever assembly is present (including no push function) it is not possible to have a push function actuated. If a push function Hall device is actuated and a standard lever assembly is installed, an error has occurred. An exemplary lever identification data format for use in a vehicle bus, e.g. a CAN bus, consistent with the present disclosure may be as follows:

Byte7Byte8AAAABBBBCCCCDDDDWhereAAAA =id for lever in position 1BBBB =id for lever in position 2CCCC =id for lever in position 3DDDD =id for lever in position 4
FIG. 26includes plots2600of sensed position error for the magnet310for a plurality of locations of the Hall devices600illustrating stability of the sensing capability of the magnets310.FIG. 27includes a plot2700of the Gauss at a Hall device2100associated with a push feature magnet702vs. push feature position illustrating reliable performance of a push circuit consistent with the present disclosure relative to the switching zone of the Hall device. As shown, on/off of the push feature may be safely determined outside of the switching zone2702associated with the push feature Hall device2100.FIG. 27includes plots2800of the Gauss at a Hall device2102associated with an ID magnet1224vs. ID magnet position illustrating reliable performance of an identification circuit consistent with the present disclosure.

According to one aspect of the disclosure, therefore, there is provided a lever assembly including: a lever; a shaft coupled to the lever for supporting pivotal movement of the lever; a magnet coupled to the lever, the magnet being configured to rotate upon pivotal movement of the lever; and a magnetic field sensor positioned adjacent the magnet for providing an output representative to position of the lever.

According to another aspect of the disclosure there is provided a system including: plurality of lever assemblies, each of the lever assemblies including at least one identification magnet coupled thereto; a plurality magnetic field sensors, each of the magnetic field sensors being positioned adjacent an associated on of the identification magnets; the magnetic field sensors providing an output associated with each of the magnets for indicating connection of the lever assemblies in the system.

According to another aspect of the disclosure there is provided A lever assembly including a lever; a shaft coupled to the lever for supporting pivotal movement of the lever; and a face gear coupled to the shaft, and a pinion gear in meshing engagement with the face gear, whereby pivotal movement of the lever causes rotational movement of the pinion gear.

According to yet another aspect of the disclosure there is provided a lever assembly including: at least one identification magnet coupled to the assembly for positioning adjacent an associated identification magnet in a PCB assembly; and at least one mating peg configured to be received in an associated receptacle in a mating portion of an associated assembly.