Manual control apparatus and method

Abstract
The invention relates to a manual control apparatus, such as a control pedal for a drive-by-wire control systems, and similar applications. According to an aspect of the invention, the manual control apparatus comprises a hysteresis mechanism that provides more precise and controllable hysteresis than previous mechanism. According to a further aspect of the invention, the manual control apparatus comprises an angular position sensor, and the angular position sensor may comprise abutments that reduce variation in the sensor. According to a still further aspect of the invention, the manual control apparatus comprises a stop pin that regulates the position of a rotatable member relative to the position sensor with less variation. The stop pin may also be used as a single fastener the holds the manual control apparatus together.
Description




BACKGROUND




The invention relates to a manual control apparatus, such as a control pedal for drive-by-wire control systems, and similar applications.




Manual control apparatuses, such as throttle control pedals for drive-by-wire throttle control systems, are known in the art. Due to the fact that such pedals eliminate the mechanical linkage to the carburetor on an engine, hysteresis is often added to replicate the “feel” of a pedal having a mechanical linkage. In particular, it is desirable for a rotatable member, for example a pedal, to generate an increased resistance during depression, and an ability stay at a fixed position with reduced force in order to avoid operator fatigue. This is typically provided by introducing a deliberate amount of frictional resistance to movement at one or more locations in the pedal mechanism. A similar effect may also be desirable in other manual control apparatuses such as a hand operated throttle, or a brake control pedal for a drive-by-wire control system, without limitation.




Although manual control apparatuses having hysteresis are known in the art, a desirable apparatus would have more precisely controlled hysteresis than is presently available. In addition, a desirable apparatus would also be light in weight, simple in manufacture, and simple in assembly with as few components as possible.




In addition to hysteresis, manual control apparatuses typically have a rotation sensor that indicates rotation of the rotatable member, for example a pedal, relative to a fixed point, such as a base to which the pedal is mounted. Precise registration of the rotatable member relative to the fixed point at a particular angle is important for both calibration, and for repeatability from apparatus to apparatus. In a throttle control pedal, the angle of rotation of the pedal is typically measured from the idle position. However, tolerance stack-up can cause a significant variation within a group of apparatuses. Tolerance stack-up and manufacturing variation may also cause significant variation within the rotation sensor. Therefore, a desirable apparatus would provide reduced variation in the rotation sensor system.




SUMMARY




According to an aspect of the invention, a spring biases a rotatable member relative to a base, and the body of the spring is forced against a friction element. The friction element rides upon a curved friction surface and is directly coupled to the rotatable member.




According to a further aspect of the invention, a manual control apparatus is provided having an angular position sensor with a housing and a pivot mounted to the housing. A rotatable member is coupled to the pivot and the angular position sensor indicates an angular position of the rotatable member. A stop pin is mounted on the housing and the rotatable member rests on the stop pin when in the idle position.




According to a still further aspect of the invention, a manual control apparatus is provided having an angular position sensor comprising a housing mounted to a base. The housing is coupled to a pivot to sense rotation thereof. The housing comprises a first abutment that defines a first datum plane perpendicular to an axis of rotation of the pivot, and a second abutment that defines a second datum plane perpendicular to the axis of rotation. A rotor within the housing is coupled to the pivot shaft, and a sensing element cooperates with the rotor to indicate an angular position thereof relative to the base. The sensing element rests upon the first abutment, and a rotor spring biases the rotor against the second abutment.




According to a still further aspect of the invention, a manual control apparatus is provided, comprising an angular position sensor comprising a housing coupled to a pivot to sense rotation thereof. The housing comprises a pair of opposing bosses that are received within recesses in a base. An idle stop is mounted to the housing and the base thereby retaining the bosses within the recesses. The housing is restrained within the base using the idle stop as a single fastener.




The manual control apparatus of the invention is particularly well suited for use with a drive-by-wire system wherein a direct mechanical linkage to an engine throttle or brake hydraulic system, for example, is eliminated.











BRIEF DESCRIPTION OF THE DRAWINGS





FIG. 1

presents a side cross-section view of a manual control apparatus according to an aspect of the invention, taken along line


1





1


of FIG.


2


.





FIG. 2

is a front view of a manual control apparatus according to an aspect of the invention.





FIG. 3

is a side cross-sectional view of a manual control apparatus according to a further aspect of the invention, taken along line


3





3


of FIG.


4


.





FIG. 4

is a front view of a manual control apparatus according to an aspect of the invention.





FIG. 5

is a side cross-sectional view of a manual control apparatus according to a further aspect of the invention.





FIG. 6

is a side cross-sectional view of a manual control apparatus according to a further aspect of the invention.





FIG. 7

is a side cross-sectional view of a manual control apparatus according to a further aspect of the invention.





FIG. 8

is a side cross-sectional view of a manual control apparatus according to a further aspect of the invention.





FIG. 9

is a side view of a throttle control pedal according to a further aspect of the invention.





FIG. 10

is a front view of the

FIG. 9

throttle control pedal.





FIG. 11

is an enlarged front view of an upper portion of the

FIG. 9

throttle control pedal with partial cross-sections.





FIG. 12

is an enlarged side view of an upper portion of the

FIG. 9

throttle control pedal with partial cross-sections taken along line


12





12


of FIG.


10


.





FIG. 13

is a perspective view of a spring according to an aspect of the invention.





FIG. 14

is a top plan view of the

FIG. 13

spring.





FIG. 15

is a top plan view of friction element according to an aspect of the invention.





FIG. 16

is a side elevational view of the

FIG. 15

friction element.





FIG. 17

is a perspective view of the

FIG. 15

friction element.





FIG. 18

is an exploded perspective view of a housing according to an aspect of the invention.





FIG. 19

is a perspective view of a base that is employed with the housing of FIG.


18


.





FIG. 20

is a perspective view of the backside of an upper portion of the

FIG. 9

throttle control assembly.











DETAILED DESCRIPTION




Various aspects of the invention are presented in

FIGS. 1-18

, which are not drawn to scale, and wherein like components in the numerous views are numbered alike. As used herein, the term “manual” refers to operation by hand, foot, or any other body part. Referring now specifically to

FIGS. 1 and 2

, a manual control apparatus


10


with hysteresis is presented according to one aspect of the invention, in this example a throttle control pedal.

FIG. 2

is a front view of the pedal, and

FIG. 1

is a cross-sectional side view taken along line


1





1


of FIG.


2


. The throttle control pedal


10


is shown mounted to a suitable structure of a motorized vehicle, such as a passenger compartment firewall


21


.




The throttle control pedal


10


comprises a base


12


having a curved friction surface


14


. A pivot


16


is mounted to the base


12


, which defines an axis of rotation


18


spaced from the curved friction surface


14


, as indicated at


20


. A rotatable member


22


, in this example a lever, is mounted to the pivot


16


, wherein the rotatable member


22


is rotatable around the axis of rotation


18


relative to the base


12


. A friction element


24


is mounted to rotate with the rotatable member


22


, spaced from the axis of rotation


18


, and forcible against the curved friction surface


14


.




The friction element


24


is directly coupled to the rotatable member


22


. As used herein, the term “directly coupled” means that the friction element is mechanically linked (as opposed to frictional coupling alone) to the rotatable member for rotation therewith so that the two rotate in unison. This is in contrast to certain prior art hysteresis mechanisms that implement only frictional coupling with the spring to induce movement of the friction element. The present invention offers a distinct advantage in that the friction element is directly forced to move with the rotatable member


22


rather than relying solely upon the presence of sufficient frictional force at the spring/friction element interface to move the friction element.




The rotatable member is biased by a spring


26


having a first end


28


, a second end


32


, and an intermediate portion


30


between the first end


28


and the second end


32


. The first end


28


is coupled to the base


12


, and the second end


32


is coupled to the rotatable member


22


. Rotation of the rotatable member


22


, as indicated by arrow


34


, forces the intermediate portion


30


against the friction element


24


, as indicated by arrow


36


, resisted by the curved friction surface


14


, as indicated by the opposing arrow


38


, thereby generating a frictional resistance to the rotation. At least two springs


26


, two friction elements


24


, and two cylindrical friction surfaces


14


are preferably provided for redundancy.




The pivot


16


comprises a shaft


40


received whithin a bearing


42


. The bearing


42


is mounted to the base


12


and the shaft


40


is fixed to the rotatable member


22


. The bearing


42


may be any type of bearing suitable for use in a throttle control pedal including, without limitation, bushings, ball bearings, needle bearings, and roller bearings.




The base


12


may configured in a variety of ways. For example, the base


12


may comprise a bottom panel


11


and two side flanges


13


extending upward from the bottom panel


11


. A stop pin


15


may be attached to the base


12


that performs multiple functions. First, the first end


28


of the spring


26


rests against it, thus restraining the first end


28


against rotation. Second, the stop pin


15


acts as an idle stop for the rotatable member


22


. As will be described more fully, the stop pin may also be used to provide accurate registration of the rotatable member


22


relative to a with a position sensor with less variation, and it may also be used as a single fastener that assembles the manual control apparatus


10


.




The rotatable member


22


may comprise a finger


23


that engages the stop pin


15


at the idle position thus preventing further rotation. The second end


32


may be fixed to the rotatable member


22


by a second pin


17


. The friction element


24


may be fixed to the rotatable member


22


by a third pin


19


that allows the friction element to rotate relative to the rotatable member


22


. The pin connection causes essentially all of the load


34


induced by the intermediate portion


30


to be transferred to the cylindrical friction surface


14


, although this is not strictly necessary in the practice of the invention as long as a substantial portion of the load


34


is transferred. A foot rest


25


may be pivotally mounted to the end of the rotatable member


22


, and may be spring biased against the rotatable member


22


if desired. Numerous variations in such minutia are possible and evident in light of the description provided herein.




Referring now to

FIGS. 3 and 4

, an angular position sensor


44


may be mounted to the base


12


that senses angular position of the shaft


40


.

FIG. 4

is a front view of the upper portion of the throttle control pedal


10


, and

FIG. 3

is a side cross-sectional view taken along line


3





3


of FIG.


4


. The various components of the throttle control pedal


10


are the same as presented in

FIGS. 1 and 2

, and numbering is not repeated here for the sake of clarity, unless needed for reference. Various angular position sensors may be employed in the practice of the invention. In the example presented, the angular position sensor


44


comprises a rotor


46


fixed to the shaft


40


. In

FIG. 3

, the rotatable member


22


is shown in phantom for reference purposes.




In the example presented, the angular position sensor


44


is a simple potentiometer. The position sensor


44


further comprises a housing


45


that encloses the rotor


46


, and an opposing pair of conductive paths


47


and


51


. The rotor


46


is provided with a pair of spring biased electrical brushes


53


electrically clamped to each other by a shunt


49


. The brushes


53


and shunt


49


provide a conductive path in combination with the conductive traces


47


and


51


. Rotating the rotatable member


22


rotates the rotor


46


which increases the length of the conductive path, and hence the resistance in proportion to the rotation of the rotatable member


22


.




A pair of conductive feed-throughs


55


are provided that may be connected to a wiring harness and appropriate electronics for converting the resistance reading to an indication of angular position. Variations are possible, and numerous suitable position sensors


44


are well known in the art. It is not intended to restrict the invention to the simple potentiometer embodiment presented herein. For example, U.S. Pat. No. 5,133,321 to Hering et al. discloses an integrated position and idle control sensor for drive-by-wire pedal assemblies, which is incorporated herein by reference.




The friction element


24


of

FIGS. 1 and 2

is configured as a shoe. It does not encircle the cylindrical friction surface


14


. However, the friction element may be configured in other shapes. As presented in

FIG. 5

, a friction element


48


is presented that is configured as a ring the encircles the curved friction surface


14


. Similarly, the curved friction surface


14


may be fully cylindrical about the axis of rotation


18


, as shown in

FIG. 5

, or may be just a sector of a cylinder.




Referring now to

FIG. 6

, another embodiment is presented that implements a friction element


50


, wherein the spring


26


is a torsional spring encircling the axis of rotation


18


. The curved friction surface


14


is a cylindrical surface concentric about the axis of rotation


18


. The friction element


50


is a ring encircling the curved friction surface


14


and comprises a protuberance


54


having a channel


52


that receives the second end


32


of the spring


26


.




Referring now to

FIG. 7

, a preferred embodiment is presented that implements the friction element


50


, wherein the spring


26


is a torsional spring encircling the friction element


50


. The torsional spring is spaced from the friction element


50


except at the intermediate portion


30


, wherein the intermediate portion


30


rests upon the friction element


50


supported by the curved friction surface


14


. The spring


26


is stressed when the throttle control pedal


10


is assembled such that a preload is exerted upon the friction element


50


at the intermediate portion


30


toward the axis of rotation


18


when the rotatable member


22


is in the idle position, as shown. The spring


26


is eccentrically offset relative to the friction element


50


when installed on the base


12


.




The inside diameter of the friction element


50


is larger than the outside diameter of the curved friction surface


14


such that a space


58


is defined therebetween, except that the spring preload deflects the friction element


50


only beneath the intermediate portion


30


of the spring


26


such that it is forced into contact with the curved friction surface


14


beneath the intermediate portion


30


. In practice, the inside diameter of the friction element


50


needs to be only slightly larger than the diameter of the curved friction surface such that a frictional resistance to rotation is generated essentially beneath the intermediate portion


30


, and not along the entire circumference of the friction surface


14


.




This feature, in combination with the spring


26


being spaced from the outside diameter of the friction element


50


, except at the intermediate portion


30


, generates an essentially pure side load during stroking of the rotatable member


22


directed toward the axis of rotation


18


. In such manner, the location where the friction element


50


generates the frictional resistance to rotation and the magnitude of the frictional resistance are precisely controlled.




According to a further aspect of the invention, a method of applying hystersis to a manual control apparatus is provided, comprising forcing an intermediate portion


30


of a spring


26


against a friction element


24


resting on a curved friction surface


14


that is part of a base


12


by rotating a rotatable member


22


about an axis of rotation


18


and rotating a second end


32


of the spring


26


with the pedal lever, a first end


28


of the spring


26


being coupled to the base


12


, the rotatable member


22


being mounted to the base


12


and the friction element being directly coupled to the rotatable member


22


.




Referring now to

FIG. 8

, an embodiment is presented identical to

FIG. 7

, except that the torsional spring


26


is replaced by a linear spring


60


having a first end


62


, and intermediate portion


64


, and a second end


66


. The spring


60


and the intermediate portion


64


function in the same manner previously described in relation to

FIG. 7

to provide a side load on the friction element


56


, and to resist depression of the rotatable member


22


. In this example, friction element


56


comprises a protuberance and pin passing through the protuberance and attached to the rotatable member


22


, which directly couples the friction element


56


and the rotatable member


22


. Although described with respect to particular embodiments, the concepts described in relation to

FIGS. 7 and 8

may be implemented in the other embodiments described herein.




Although described in relation to a rotatable member


22


that is a lever with reference to

FIGS. 1-8

, any manually rotatable member may be implemented in the practice of the invention with any control apparatus such as a throttle control, a brake control, or other manual control adaptable for use with the invention, without limitation.




Referring now to

FIGS. 9 and 10

, side and front views, respectively, of a throttle control pedal


100


with hysteresis are presented according to a further aspect of the invention.

FIG. 11

presents an enlarged view of the upper portion of

FIG. 9

with partial cross-sections of selected portions. The throttle control pedal


100


is shown mounted to a suitable structure of a motorized vehicle, such as a passenger compartment firewall


121


.




Referring to

FIGS. 9-11

, The throttle control pedal


100


comprises a base


112


comprising a frame


111


and a housing


113


The housing


113


has a curved friction surface


114


, as shown in FIG.


11


. As used herein, the term “base” is intended to mean a non-rotating structure to which the lever is coupled, and any non-rotating structure mounted to the base. Thus, the housing


113


and frame


111


are both members of the base


112


.




A pivot


116


is mounted to the base


112


that defines an axis of rotation


118


spaced from the curved friction surface


114


. The curved friction surface


114


is cylindrical about the axis of rotation


118


, and the pivot


116


comprises a shaft


140


received within a bearing


142


mounted to the housing


113


. A lever


122


is fixed to the shaft


140


. A foot rest


121


is pivotally attached to the lever


122


. A friction ring


150


is mounted to rotate with the lever


122


, spaced from the axis of rotation


118


, encircling the curved friction surface


114


and forcible against the curved friction surface


114


.




A torsional spring


126


encircles the friction ring


150


. The torsional spring has a first end


128


, a second end


132


, and an intermediate portion


130


between the first end


128


and the second end


132


. The first end


128


is fixed to the base


112


and the second end


132


is fixed to the lever


122


. Rotation of the lever


122


forces the intermediate portion


130


against the friction ring


150


resisted by the curved friction surface


114


thereby generating a frictional resistance to the rotation through the friction ring


150


. Thus, the principle of operation of throttle control pedal


100


is identical to that of the throttle control pedal


10


of

FIGS. 1 and 2

.




As previously described in relation to

FIG. 7

, a small space


158


is defined between the friction ring


150


and the curved friction surface


114


, except beneath the intermediate portion


130


of the spring


126


where the friction ring


150


rests upon the curved friction surface


114


due to preload in the spring


126


.




A stop pin


115


is mounted to the base


112


and the lever


122


is provided with a finger


123


that engages the stop pin


115


in the idle position. The lever


122


also comprises a cross bar


117


that engages the second end


132


of the spring


126


. The base


12


also comprises a lower stop


120


that stops further pivoting of the lever


122


at full depression.




Referring now to

FIG. 12

, a side cross-sectional view of the upper part of the throttle control pedal


100


through the housing


113


taken along line


12





12


of

FIG. 10

is presented. The friction ring


150


comprises an outside cylindrical surface


151


and a protuberance


152


extending therefrom. The protuberance


152


has a channel


154


that receives the second end


132


of spring


126


. The cross bar


117


is shown for reference, and preferably rides on the protuberance


152


. Preferably, the protuberance


152


and cross bar


117


rotate concentric with the axis of rotation


118


so that the cross bar


117


does not slide on the surface of the protuberance while the lever


122


is depressed.




Referring now to

FIG. 13

, a perspective view of a spring


127


that may be used in the practice of the invention is presented. Spring


127


comprises a first end


129


, an intermediate portion


131


, and a second end


133


, and is identical to spring


126


except the first end


129


is shorter than the first end


128


of spring


126


. Such variations may be made for particular applications without departing from the invention. Referring now to

FIG. 13

, a top plan view of the spring


127


is presented in an unstressed state. The spring


127


is preloaded when installed with the pedal


122


in the idle position, as indicated by the phantom position


134


of the second spring end


133


. Full load is indicated by phantom position


136


of the second spring end


133


.




Referring now to

FIGS. 15

,


16


and


17


, a top plan view, a side elevational view, and a perspective view, respectively, are presented of a friction element


160


configured as a ring according to a further aspect of the invention. The friction element


160


comprises an outside surface


161


, and a protuberance


162


extending from the outside cylindrical surface


161


having a channel


164


that receives a spring end, as previously described herein. According to a further aspect of the invention, the outside cylindrical surface


161


comprises a spacer


166


having a predetermined thickness


168


above the surface


161


, and the protuberance


162


extends from the spacer


166


. The protuberance


162


and the spacer


166


couple the torsional spring


126


or


127


(shown in phantom) relative to the friction ring or element


160


such that in an unstressed state a space is defined between the torsional spring and the friction ring encircling the friction ring and interrupted by the spacer. The second end


132


or


133


(shown in phantom) is received within the channel


164


. The friction element


160


may also comprise a rim


170


extending outwardly from the outside cylindrical surface


161


. Upon installing the friction element


160


and spring assembly into a pedal assembly


10


at an idle position, preloads the spring, and causes the intermediate portion of the spring to be forced into contact with the friction ring


160


, as previously described, thus interrupting the space


172


at another location.




Referring now to

FIG. 18

, an exploded perspective view of the housing


113


is presented, along with components attached to the housing


113


. The housing


113


includes an angular position sensor


144


that is coupled to the pivot to sense rotation thereof. In the example presented, the angular position sensor comprises a rotor


146


coupled to the shaft


140


, and a sensing element


147


fixed to the housing. Terminals


149


are provided that mate with the sensing element, and that are connected to an external electrical connector


170


for connection to a wire harness. An internal spring


200


and an O-ring may


202


may also be provided.




The housing


113


comprises a first abutment


172


that defines a first datum plane perpendicular to the axis of rotation


118


and a second abutment


174


that defines a second datum plane perpendicular to the axis of rotation


118


. The pivot shaft is received within an opening


176


in the housing


45


. The sensing element


147


cooperates with the rotor


146


to indicate an angular position thereof relative to the base


112


.




The sensing element


147


rests upon the first abutment


172


and a rotor spring


178


biases the rotor


146


against the second abutment


174


. Thus, the sensing element


147


and the rotor


146


are accurately positioned relative to each other, and the positioning is not dependent accuracy in joining the first and second halves of the housing


113


.




In the example presented, the first and second abutments


172


and


174


are curved ridges molded in the left half of the housing


113


. One or more further structures may be added, such as a nipple


180


that position the sensing element


147


within the first datum plane. If the axis of rotation


118


is viewed as a Z-axis, then the X and Y axes lie in the first datum plane, as determined by the first abutment


172


, and the nipples


180


position the sensing element relative to the X and Y axes. Thus, the sensing element


180


may be accurately positioned in all three spatial dimensions relative to the rotor


146


. Innumerable variations are possible in light of the description provided herein.




In the example presented, the rotor spring


178


comprises at least one tab


182


that is integral with the rotor


146


. Two opposing tabs


182


are preferably provided. The tab


182


bears against the right half of housing


113


and biases the rotor


146


against the second abutment


174


. The tab


182


may be provided with a spherical bump


184


that focuses the spring load onto a predefined area of the housing


113


. The housing


113


may also comprise a third abutment, the backside of which indicated at


186


, that the rotor spring


178


bears against. In the example presented, the third abutment


186


is a curved ridge and serves as a track upon which the spherical bump


184


rides. Innumerable variations are possible in light of the description provided herein.




Referring now to

FIG. 19

, a perspective view of the base


112


is provided. According to a further aspect of the invention, the base


112


comprises a pair of recesses


188


. The housing


113


comprises a pair of opposing bosses


190


(

FIG. 18

) that are received within the recesses


188


. The stop pin


115


couples the housing to the base thereby retaining the bosses


190


within the recesses


188


. The housing


113


is provided with a stop pin hole


124


tht receives the stop pin


115


.




This is further illustrated in

FIG. 20

wherein a perspective view is presented of the backside of the upper portion of the throttle control pedal


100


of FIG.


9


. The bosses


190


closely conform to the recesses


188


, which open in the same direction. The stop pin


115


is located on a side opposite from that direction. In the embodiment presented, the recesses


188


are C-shaped and formed in a pair of side flanges


192


that extend upward from a bottom panel


194


, and the bosses


190


are cylindrical. The housing


113


is captive in all directions within the bracket


112


. The stop pin


115


serves as a single fastener that holds the assembly together.




As presented in

FIGS. 18

,


19


, and


20


, the recesses


188


are provided with slots


196


, and the bosses


190


are provided with ears


198


that are received within the slots


196


. The slots


196


and ears


198


assist in assembly. During assembly, the bosses


190


are slid into the recesses


188


with a rotation that presses the ears


198


into the slots. This movement rotates the stop pin hole


124


toward the bottom panel


196


of the base


112


until it aligns with the stop pin


115


, after which the stop pin is inserted into the stop pin hole


124


. According to a preferred embodiment, approximately 50% of the force applied to the pedal during depression is resisted by hysteresis, the balance by the springs. The base is formed from metal, cast or stamped, and is covered with a coating having good dry lubricating properties, such as zinc dichromate or epoxy paint. The bearings are self lubricating and are press fit into the housing. Porous metal or plastic bearings impregnated with oil are desirable. The housing may be formed from a reinforced plastic, injected molded, such as a 30% glass filled polyester. The friction elements may be formed from plastic, such as polyacetol or a fluorpolymer, preferably unreinforced by fiber. The rotor may be formed from plastic and is preferably integrally molded onto the shaft. The sensing element is preferably a ceramic resistance element.




Two biasing/hysteresis springs are preferably provided. The hysteresis force is directly generated by the springs, so that if a spring breaks, the spring ceases to generate hysteresis. Thus, the total hysteresis is always proportional to the spring force.




According to a further aspect of the invention, with reference to

FIGS. 1-20

and the description provided herein with respect to those figures, a manual control apparatus is provided, comprising:




a base;




a pivot mounted to said base that defines an axis of rotation spaced from said curved friction surface;




a rotatable member coupled to said pivot, wherein said rotatable member is rotatable around said axis of rotation relative to said base;




an angular position sensor comprising a housing fixed to said base and coupled to said pivot to sense rotation thereof;




a stop fixed to said housing; and,




a spring coupled to said rotatable member and said base, said spring biasing said rotatable member against said stop.




According to a further aspect of the invention, a manual control apparatus is provided, comprising:




a base comprising a pair of recesses;




a pivot mounted to said base that defines an axis of rotation;




a rotatable member coupled to said pivot, wherein said rotatable member is rotatable around said axis of rotation relative to said base;




an angular position sensor comprising a housing coupled to said pivot to sense rotation thereof, said housing comprising a pair of opposing bosses that are received within said recesses;




a stop coupled to said housing and said base thereby retaining said bosses within said recesses; and,




a spring coupled to said rotatable member and said base, said spring biasing said rotatable member against said stop.




According to a further aspect of the invention, a manually operable throttle control is provided, comprising:




a base;




a manually operable control lever for controlling a throttle position;




an electrical sensor for sensing the angular position of said lever and for outputting an electrical signal related to said lever position;




a shaft rotatably mounted on said base and drivingly connecting said lever with said sensor, said sensor and said shaft being relatively rotatable;




a pin securing said sensor on said base and fixing the rotational position of said sensor relative to said shaft and said lever.




Said pin may include a portion forming stop engagable by said lever to limit the rotation of said lever, and said lever includes a surface engagable with said stop portion of said pin.




Said base may include a pair of spaced apart flanges, said sensor may includes a through-hole therein, and said pin passes through said through-hole and is secured to said flanges.




Said pin may include an extension on one end thereof extending outwardly beyond one of said flanges, and said stop portion is defined on said pin extension.




At least one torsion spring may be wrapped around said drive shaft, said spring having a free end engaging pin whereby to restrain said spring against rotation about said drive shaft.




According to a further aspect of the invention, a manually operable throttle control is provided, comprising:




a base;




a manually operable control lever displaceable for controlling a throttle position;




an electrical sensor for sensing the displacement position of said lever and for outputting an electrical signal related to said lever position;




a shaft carried on said base and connecting said lever with said sensor; and,




a locating pin carried on said base for locating the rotational position of said sensor relative to said displacement position of said lever.




Although the invention has been described and illustrated with reference to specific illustrative embodiments thereof, it is not intended that the invention be limited to those illustrative embodiments. Those skilled in the art will recognize that variations and modifications can be made without departing from the true scope and spirit of the invention as defined by the claims that follow. It is therefore intended to include within the invention all such variations and modifications as fall within the scope of the appended claims and equivalents thereof.



Claims
  • 1. A manual control apparatus, comprising:(a) a base; (b) a pivot mounted to said base that defines an axis of rotation, said pivot comprising a pivot shaft; and (c) an angular position sensor comprising a housing fixed to said base and coupled to said pivot to sense rotation thereof, said housing comprising a first abutment that defines a first datum plane perpendicular to said axis of rotation and a second abutment that defines a second datum plane perpendicular to said axis of rotation, wherein the first and second abutments are integrally molded in the housing, a rotor within said housing fixed to said pivot shaft, said pivot shaft being received within an opening in said housing, a sensing element comprising a surface having electrically conductive paths thereon in sliding electrical contact with the rotor to indicate an angular position thereof relative to said base, said sensing element resting upon said first abutment and said sensing element surface being substantially in a single plane parallel to the first datum plane, and a rotor spring biasing said rotor in sliding contact against said second abutment.
  • 2. The apparatus of claim 1, wherein said housing comprises a third abutment and said rotor spring bears in sliding contact against said third abutment.
  • 3. The apparatus claim 2, wherein said rotor spring comprises at least one tab integral with said rotor that bears against said third abutment.
  • 4. The apparatus of claim 1, wherein said rotor spring is integral with said rotor.
  • 5. The apparatus of claim 1, wherein said sensing element is generally in a plane perpendicular to said axis of rotation.
  • 6. The apparatus of claim 1, wherein said housing further comprises one or more protrusions in contact with the sensing element to support the sensing element in a predetermined position.
  • 7. The apparatus of claim 2, wherein the housing comprises a separable first half and a separable second half wherein said first and second abutments are on said first half.
  • 8. The apparatus of claim 1, wherein the housing further comprises a curved friction surface spaced apart from said pivot.
  • 9. The apparatus of claim 1, wherein the first abutment and second abutment are arcuate and concentric about the axis of rotation.
  • 10. The apparatus of claim 9, wherein the first abutment is a first radial distance from the axis of rotation and the second abutment is a second radial distance from the axis of rotation, said first radial distance being greater than said second radial distance.
  • 11. The apparatus of claim 7, wherein said third abutment is on said second half of the housing.
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