Speed shift indicator
First Claim
1. A speed shift indicating device for a vehicle driven by an internal combustion engine having an ignition system, the vehicle having a manually controlled transmission, the speed shift indicating device comprising:
- trigger means for receiving an input electrical signal having a repetition rate indicative of engine RPM and providing trigger pulses in response to the input electrical signal;
timer means having an output which has first and second states, the timer means output switching to the first state in response to a trigger pulse and remaining in the first state only for a first time period unless another trigger pulse is received before the end of the first time period;
adjusting means for adjusting the first time period;
annunciator means to indicate, when energized, the need to shift the transmission; and
annunciator control means for energizing the annunciator means only if the timer means output remains in the first state for at least a second time period greater than the first time period.
0 Assignments
0 Petitions
Accused Products
Abstract
A speed shift indicating device is mounted in the driver compartment of a motor vehicle and is connected to the ignition system by a single wire which extends from the driver compartment through the firewall and into the engine compartment. The single wire derives from the ignition system an electrical input signal having a repetition rate indicative of engine revolutions per minute (RPM). The speed shift indicating device has an electrical circuit connected to the single wire for receiving an input electrical signal which has a repetition rate indicative of engine RPM. Trigger pulses are produced in response to the input electrical signal and are supplied to a timer. The output of the timer switches to a first state in response to each trigger pulse and remains in the first state only for a first time period unless another trigger pulse is received before the end of the first time period. The first time period is adjustable by the driver. An annunciator is energized to indicate that the engine has attained a speed at which shifting of the transmission should be done only if the output of the timer remains in the first state for at least a second time period which is greater than the first time period.
21 Citations
11 Claims
-
1. A speed shift indicating device for a vehicle driven by an internal combustion engine having an ignition system, the vehicle having a manually controlled transmission, the speed shift indicating device comprising:
-
trigger means for receiving an input electrical signal having a repetition rate indicative of engine RPM and providing trigger pulses in response to the input electrical signal; timer means having an output which has first and second states, the timer means output switching to the first state in response to a trigger pulse and remaining in the first state only for a first time period unless another trigger pulse is received before the end of the first time period; adjusting means for adjusting the first time period; annunciator means to indicate, when energized, the need to shift the transmission; and annunciator control means for energizing the annunciator means only if the timer means output remains in the first state for at least a second time period greater than the first time period. - View Dependent Claims (2, 3, 4, 5, 6, 7, 8, 9)
-
-
10. For use in a vehicle having an engine compartment and a driver compartment separated by a firewall, the vehicle being driven by an internal combustion engine having an ignition system located in the engine compartment, the vehicle having a multiple-gear ratio transmission connected between the engine and the driven wheels of the vehicle with manually controlled shift means located in the driver compartment for shifting the gear ratio of the transmission, the invention comprising:
-
a single wire extending from the driver compartment through the firewall into the engine compartment and connected to the ignition system to derive an input electrical signal having a repetition rate indicative of engine RPM; and a speed shift indicating device located in the driver compartment, the speed shift indicating device having an electrical circuit connected to the single wire for receiving the input electrical signal and actuating annunciator means when the repetition rate of the input electrical signal exceeds a driver-selected repetition rate. - View Dependent Claims (11)
-
Specification