WE CLAIM
1. An engine mounted speed sensor assembly 60 arrangement in the existing
system of a vehicle having (a) an engine 10, (b) a driven shaft 20, (c) a
rear wheel axle 30, (d) a first gear 40, (e) a second gear 50, (f) a speed
5 sensor assembly 60, (g) a sensing surface 62, and (h) an engine crankcase
70, wherein:
(i) The engine 10 is swingable mounted on the vehicle such that the driven shaft 20 is connected with the rear wheel axle 30 of the vehicle;
10 (ii) The driven shaft 20 is connected to a crankshaft through a
continuously variable transmission (CVT) mechanism comprising a drive pulley and a driven pulley connected through a V-belt;
(iii) The drive pulley is connected with the crankshaft, both the drive
pulley and driven pulley includes a fixed pulley half and an axially
15 movable pulley half;
(iv) The driven side pulley is connected with the driven shaft 20 through a centrifugal clutch;
(v) The first gear 40 and the second gear 50 are of a reduction gear
train which connects the driven shaft 20 with the rear wheel axle
20 30;
(vi) The speed sensor assembly 60 has a permanent magnet, a Wheatstone bridge with at least one Giant Magnetoresistive (GMR) element and a signal conditioning circuit;
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(vii) A housing for enclosing, at least, a speed sensor assembly
and for attaching the speed sensor assembly with an engine crankcase 70; and
(viii) A blind hole is provided in the engine crankcase for
5 attaching the speed sensor assembly such that a portion of the
engine crankcase separates the speed sensor assembly from rotating engine component.
2. The engine mounted speed sensor assembly 60 arrangement of Claim 1,
10 wherein the signal conditioning circuit of the speed sensor assembly 60
converts the Wheatstone bridge output into Transistor-Transistor Logic (TTL) pulses that can be processed by an electronic control unit (ECU).
3. The engine mounted speed sensor assembly 60 arrangement of Claim 1,
wherein the engine crankcase 70 separates the sensing surface 62 of the
15 speed sensor assembly from the second gear 50.
4. The engine mounted speed sensor assembly 60 arrangement of Claim 1,
wherein the speed sensor assembly 60 housing can also include the signal
conditioning and power supply circuitry.
5. The engine mounted speed sensor assembly 60 arrangement of Claim 1,
20 wherein the sensing surface 62 is made of a paramagnetic material like
aluminium.
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6. The engine mounted speed sensor assembly 60 arrangement of Claim 1,
the speed sensor assembly 60 can be an integrated circuit comprising the
speed sensor assembly, magnet, signal conditioning circuit and the power
supply circuit, and the signals indicative of rotational speed of gear or
5 shaft can be generate by the sensor.
7. The engine mounted speed sensor assembly 60 arrangement of Claim 1,
the speed sensor assembly 60 can be used in all vehicles with internal
combustion engines and also for lawnmowers or stationary gen-sets.
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DATED THIS 20th DAY OF MARCH 2017.
20 (MS.ANURADHA VAIDYANATHAN)
AGENT FOR THE APPLICANT
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