Claims Analysis
Total Claims: 14
Claim 1
Independent Claim
339 words
Combined rotary speed and angular position determination system, to determined the angular speed and the instantaneous angular position of a reference point of a rotating shaft, to provide both a speed signal and a reference signal representative, respectively, of the speed of the shaft and the predetermined angular position of the shaft, comprising the combination of a star wheel (10, 20) having a toothed circumference; at least one reference element (11, 21) located on the star wheel and placed thereon at a predetermined angular position with respect to said reference point including a pin (11, 12) extending transversely through the wheel and parallel to the axis thereof; a stationary electromagnetic pickup having a magnetic yoke (12, 14, 15) located in magnetically coupled relationship both with respect to the toothed circumference of the star wheel and the location of said reference element on the star wheel when the reference element and the yoke are in angular alignment, the core or yoke being formed with extending arms (14, 15) reaching around the toothed edge portion of the wheel (10) and extending to face the end portions of the reference element pin (11) when the reference element is in a position opposite the pick-up, the teeth and gaps of the star wheel and the yoke of the pick-up forming a first magnetic circuit, the reference element and the yoke of the pickup forming a second magnetic circuit, whereby the yoke will be common to both said magnetic circuits; and means (13) deriving an electrical output signal from the yoke (12, 14 15) of said pick-up representative of the change in the magnetic reluctance of both said magnetic circuits to provide said speed signal as the first magnetic circuit changes its magnetic reluctance cyclically upon rotation of the shaft, thereby causing cyclical flux changes and having an additional characteristic representative of the additional change in the reluctance introduced by the second magnetic circuit upon passage of the reference element (11, 21) past the yoke of said pick-up and to provide said reference signal.
Claim 2
Dependent Claim
339 words
Combined rotary speed and angular position determination system, to determined the angular speed and the instantaneous angular position of a reference point of a rotating shaft, to provide both a speed signal and a reference signal representative, respectively, of the speed of the shaft and the predetermined angular position of the shaft, comprising the combination of a star wheel (10, 20) having a toothed circumference; at least one reference element (11, 21) located on the star wheel and placed thereon at a predetermined angular position with respect to said reference point including a pin (11, 12) extending transversely through the wheel and parallel to the axis thereof; a stationary electromagnetic pickup having a magnetic yoke (12, 14, 15) located in magnetically coupled relationship both with respect to the toothed circumference of the star wheel and the location of said reference element on the star wheel when the reference element and the yoke are in angular alignment, the core or yoke being formed with extending arms (14, 15) reaching around the toothed edge portion of the wheel (10) and extending to face the end portions of the reference element pin (11) when the reference element is in a position opposite the pick-up, the teeth and gaps of the star wheel and the yoke of the pick-up forming a first magnetic circuit, the reference element and the yoke of the pickup forming a second magnetic circuit, whereby the yoke will be common to both said magnetic circuits; and means (13) deriving an electrical output signal from the yoke (12, 14 15) of said pick-up representative of the change in the magnetic reluctance of both said magnetic circuits to provide said speed signal as the first magnetic circuit changes its magnetic reluctance cyclically upon rotation of the shaft, thereby causing cyclical flux changes and having an additional characteristic representative of the additional change in the reluctance introduced by the second magnetic circuit upon passage of the reference element (11, 21) past the yoke of said pick-up and to provide said reference signal.
Claim 3
Dependent Claim
24 words
System according to claim 1, wherein the means deriving the electrical output signal comprises a coil (13) and the pickup is a coil-core combination.
Claim 4
Dependent Claim
20 words
System according to claim 1, wherein the means deriving the electrical output signal includes a solid state magnetically field-responsive element.
Claim 5
Dependent Claim
17 words
System according to claim 1, wherein the means deriving the electrical output signal comprises a Hall generator.
Claim 6
Dependent Claim
19 words
System according to claim 1, wherein the means deriving the electrical output signal comprises a magnetic field sensor plate.
Claim 7
Dependent Claim
30 words
System according to claim 1, wherein the reference element (11) is located on a radial line passing through the center of a tooth and the center of the wheel (10).
Claim 8
Dependent Claim
34 words
System according to claim 1, wherein the reference element (21) is located on a radial line passing through the center of the gap between adjacent teeth and the center of the star wheel (20).
Claim 9
Dependent Claim
19 words
System according to claim 1, wherein the reference element (11, 21) comprises a material having, magnetically highly conductive characteristics.
Claim 10
Dependent Claim
16 words
System according to claim 1, wherein the pin extends beyond the end faces of the wheel.
Claim 11
Dependent Claim
12 words
System according to claim 8, wherein the material has soft iron characteristics.
Claim 12
Dependent Claim
14 words
System according to claim 1 wherein the reference element comprises a permanently magnetized pin.
Claim 13
Dependent Claim
18 words
System according to claim 1, wherein the means deriving the electrical output signal includes an integrator circuit (26).
Claim 14
Dependent Claim
49 words
System to determine the rotary speed and an instantaneous angular position of an internal combustion engine, the crankshaft being coupled to a starter gear, comprising the system of claim 1 wherein the starter gear forms said star wheel (10, 20), the gear teeth (10', 20') defining said toothed circumference.