Timer Relay Capacitor Engine Cranking System
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Solution Overview
Problem
Existing engine cranking systems for heavy-duty trucks face issues with battery drainage from auxiliary loads when the engine is not running, leading to failed starts, and often rely on vehicle programming or oil-pressure sensors, with capacitors either losing charge or being isolated from the cranking motor.
Innovation Solution
An improved engine cranking system that includes a capacitor and a control circuit with a timer relay, allowing the capacitor to power the cranking motor even when batteries are discharged, and operates independently of vehicle programming, with the capacitor being isolated when not in use to prevent discharge.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Reliability
If a capacitor is used to supplement vehicle batteries for engine starting, then the vehicle can be started even after battery drainage from auxiliary loads, but the capacitor may lose its charge over time by leaking through diodes if not completely isolated
Solution Approach 1:
A timer relay is introduced as an intermediary component to control the electrical connection between the capacitor and the rest of the system. The timer relay acts as a smart switch that opens the circuit after a predetermined time period, completely isolating the capacitor to prevent charge leakage through diodes, while still allowing the capacitor to function as intended for engine starting
2Loss of energy
If the capacitor is completely isolated when not in use to prevent charge loss, then charge leakage is eliminated, but the capacitor cannot be used to close the switch or relay to bring the capacitor on line
Solution Approach 1:
The timer relay is configured to automatically close the circuit a predetermined time period before the engine is actually cranked. This preliminary action allows the capacitor to be connected to the system in advance, enabling it to close switches or relays as needed, while still being completely isolated afterward to prevent charge leakage
3Adaptability or versatility
If existing systems use vehicle programming or oil-pressure sensors to control capacitor connection, then the system can respond to engine running conditions, but the system cannot be implemented as a self-contained unit and requires vehicle integration
Solution Approach 1:
The timer relay is designed to automatically detect and respond to cranking conditions without requiring external vehicle programming or oil-pressure sensors. The system serves itself by using the timer relay's internal timing mechanism to control capacitor connection and isolation, making it a self-contained unit that can be independently implemented
4Adaptability or versatility
If the capacitor is connected to the system during engine running to detect conditions, then the system can respond to operational status, but the capacitor may discharge when it should remain isolated
Solution Approach 1:
The timer relay dynamically controls the capacitor's connection status based on predetermined time periods. The system transitions from a static connection state to a dynamic state where the capacitor is connected only during specific time windows before cranking and completely isolated afterward, optimizing both detection capability and charge preservation
Applied Scientific Principles
This section explains which scientific principles are used to turn an abstract innovation direction into a practical engineering solution.
Function Achieved in This Case
Enables reliable engine starting without batteries, reduces capacitor discharge, and eliminates the need for oil-pressure sensors, providing a self-contained solution for cranking systems.
Implementation Method 1
a capacitor with first and second capacitor terminals
Implementation Method 2
a timer relay operative to switch, in response to whether a predetermined period of time has elapsed, between a first open-circuit condition, in which the timer relay interrupts a second electrical path, and a first closed-circuit condition
Data Source
AI summary
An engine cranking system and a method of cranking an engine are provided. The engine cranking system comprises an engine, cranking motor, and capacitor. The engine cranking system further comprises an electrical path interconnecting the cranking motor or a battery to the capacitor. The engine cranking system further comprises a control circuit coupled to the capacitor. The control circuit comprises a timer operative to track temporal information. The control circuit is operative to apply a control voltage that varies in response to the tracked temporal information. The control circuit further comprises a relay included in the electrical path. The relay is operative to switch, in response to the control voltage, between an open-circuit condition, in which the relay interrupts the electrical path, and a closed-circuit condition.