Electric starting system
First Claim
1. An electric starting system for cranking an engine comprising, a source of direct voltage, an electric cranking motor having an armature, a series field winding and a shunt field winding, a shaft driven by said armature carrying a pinion that is adapted to be meshed with the ring gear of an engine to be cranked, a solenoid having a pull-in coil, a hold-in coil and a shiftable plunger, means connecting said plunger and pinion such that shiftable movement of said plunger causes said pinion to shift, a start switch, means connecting one side of said start switch to a first side of said voltage source, a first circuit connected between the opposite side of said start switch and a second side of said voltage source comprising in a series connection said solenoid hold-in coil and said shunt field winding, and a second circuit connected between said opposite side of said start switch and said second side of said voltage source, said second circuit connected in parallel with said first circuit and comprising in a series connection, said solenoid pull-in coil, said series field and the armature winding of said armature.
1 Assignment
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Accused Products
Abstract
An electric starting system for cranking an internal combustion engine that utilizes a starter having a solenoid that is provided with pull-in and hold-in coils. The solenoid includes a plunger which when shifted operates solenoid switch contacts and shifts a pinion into mesh with the ring gear of the engine to be cranked. The electric starting motor has series and shunt field coils and during cranking operation the shunt field is energized through the hold-in coil of the solenoid and the series field is energized through the pull-in coil of the solenoid. This mode of energization produces a small indexing torque that slowly rotates the pinion when end tooth abutment occurs between the pinion and the ring gear.
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Citations
4 Claims
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1. An electric starting system for cranking an engine comprising, a source of direct voltage, an electric cranking motor having an armature, a series field winding and a shunt field winding, a shaft driven by said armature carrying a pinion that is adapted to be meshed with the ring gear of an engine to be cranked, a solenoid having a pull-in coil, a hold-in coil and a shiftable plunger, means connecting said plunger and pinion such that shiftable movement of said plunger causes said pinion to shift, a start switch, means connecting one side of said start switch to a first side of said voltage source, a first circuit connected between the opposite side of said start switch and a second side of said voltage source comprising in a series connection said solenoid hold-in coil and said shunt field winding, and a second circuit connected between said opposite side of said start switch and said second side of said voltage source, said second circuit connected in parallel with said first circuit and comprising in a series connection, said solenoid pull-in coil, said series field and the armature winding of said armature.
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2. An electric starting system for cranking an engine comprising, a source of direct voltage, an electric cranking motor having an armature, a series field winding and a shunt field winding, a shaft driven by said armature, a pinion slidably supported on and driven by said armature shaft that is adapted to be meshed with the ring gear of an engine to be cranked, a solenoid having a pull-in coil, a hold-in coil and a shiftable plunger, means connecting said plunger and pinion such that shiftable movement of said plunger causes said pinion to shift, a start switch, means operative when said start switch is closed and said pinion is in end tooth abutment with said ring gear to energize said cranking motor from said voltage source in a first mode of energization wherein said solenoid hold-in coil and said shunt field winding are connected in series and across said voltage source and said solenoid pull-in coil, series field winding and the armature winding of said armature are connected in series and across said voltage source, said motor when operating in said first mode of energization developing a small indexing torque for rotating said pinion to a position where it can mesh with said ring gear, and means operative when said pinion is meshed with said ring gear for energizing said motor in a second mode of energization wherein said hold-in coil and shunt field winding are series connected across said voltage source, said series field winding and armatue winding and series connected across said voltage source and said pull-in coil is short circuited, said motor when operating in said second mode of energization developing full cranking torque as a compound motor.
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3. An electric starting system for cranking an engine comprising, a source of direct voltage, an electric cranking motor having an armature, a series field winding and a shunt field winding, a shaft driven by said armature slidably supporting and rotatably driving a pinion that is adapted to be meshed with the ring gear of an engine to be cranked, a solenoid having a pull-in coil, a hold-in coil and a shiftable plunger, means connecting said plunger and pinion such that shiftable movement of said plunger causes said pinion to shift, solenoid switch means which is operated to a closed condition by said plunger when said pinion is fully meshed with said ring gear, a start switch, means connecting one side of said start switch to a first side of said voltage source, a first circuit connected between the opposite side of said start switch and a second side of said voltage source comprising in a series connection said solenoid hold-in coil and said shunt field winding, and a second circuit connected between said opposite side of said start switch and said second side of said voltage source, said second circuit connected in parallel with said first circuit and comprising in a series connection, said solenoid pull-in coil, said series field and the armature winding of said armature, said first and second circuits energizing said field windings and armature winding such that the motor develops a small torque to rotate the armature shaft and pinion slowly when said solenoid switch means is in an open condition, said solenoid switch means when closed connecting the series field winding and armature winding of said motor directly across said voltage source and short circuiting said pull-in coil whereby said motor develops full torque output to crank the engine.
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4. An electric starting system for cranking an engine comprising, a source of direct voltage, an electric cranking motor having an armature, a series field winding and a shunt field winding, a shaft driven by said armature, a pinion slidably supported by said shaft and rotatably driven thereby that is adapted to be meshed with the ring gear of an engine to be cranked, a solenoid having a pull-in coil, a hold-in coil and a shiftable plunger, means connecting said plunger and pinion such that shiftable movement of said plunger causes said pinion to shift, a solenoid switch operated by said plunger that is actuated to a closed condition when said pinion is fully meshed with said ring gear and which is in an open condition when end tooth abutment occurs between said pinion and ring gear, a start switch, means connecting one side of said start switch to a first side of said voltage source, a first circuit connected between the opposite side of said start switch and a second side of said voltage source comprising in a series connection said solenoid hold-in coil and said shunt field winding, and a second circuit connected between said opposite side of said start switch and said second side of said voltage source, said second circuit connected in parallel with said first circuit and comprising in a series connection, said solenoid pull-in coil, said series field and the armature winding of said armature, said first and second circuits energizing said field windings and armature winding such that the motor develops a small indexing torque to rotate the armature shaft and pinion slowly when end tooth abutment occurs and said solenoid switch is open, said solenoid coils causing said pinion to mesh with said ring gear after said pinion has been rotated to a meshing position, said solenoid switch closing when said pinion meshes with said ring gear and said solenoid switch in a closed condition connecting the series field winding and armature winding of said motor directly across said voltage source and short circuiting said pull-in coil whereby said motor develops full torque output to crank the engine.
Specification