Automatic reverse motor controller
First Claim
1. A controller for an electric motor powered by a power source, the controller comprising:
- a trigger switch capable of being coupled to the power source;
a secondary switch coupled in a parallel path to the trigger switch;
a power supply circuit coupled to the trigger switch;
a commutator coupled to the trigger and secondary switches; and
a programmable device coupled to the power supply circuit, the trigger switch, and the commutator, the programmable device operable to sense actuation and deactuation of the trigger switch, read an electromotive force from the trigger switch, and, upon sensing deactuation of the trigger switch, send a control signal to the commutator to reverse current flow therethrough for a predetermined amount of time, and deactuate the secondary switch when the predetermined time has lapsed.
1 Assignment
0 Petitions
Accused Products
Abstract
A method and apparatus to automatically reverse the motor of a dispensing gun or similar tool. The invention includes a controller that automatically reverses the direction of plunger movement and removes the plunger from contact with the back wall of a cartridge. The controller has a trigger switch that is coupled to a power source, such as a battery, and includes a main power on/off switch and a potentiometer. A protection or secondary switch is coupled in parallel to the main power on/off switch. A power supply circuit and a commutator are each coupled to the main and secondary switches. An overload sensor is coupled to the commutator. The controller includes a programmable device that is coupled to the power supply circuit, the potentiometer, the commutator, and the overload sensor. The programmable device is operable to sense actuation and deactuation of the main power on/off switch, read an electromotive force from the potentiometer, and, upon sensing deactuation of the main switch, send a control signal to the commutator to reverse current flow therethrough for a predetermined amount of time, and deactuate the secondary switch when the predetermined time has lapsed.
71 Citations
33 Claims
-
1. A controller for an electric motor powered by a power source, the controller comprising:
-
a trigger switch capable of being coupled to the power source;
a secondary switch coupled in a parallel path to the trigger switch;
a power supply circuit coupled to the trigger switch;
a commutator coupled to the trigger and secondary switches; and
a programmable device coupled to the power supply circuit, the trigger switch, and the commutator, the programmable device operable to sense actuation and deactuation of the trigger switch, read an electromotive force from the trigger switch, and, upon sensing deactuation of the trigger switch, send a control signal to the commutator to reverse current flow therethrough for a predetermined amount of time, and deactuate the secondary switch when the predetermined time has lapsed. - View Dependent Claims (2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15)
-
-
16. A method of reversing an electric motor in a power tool that is coupled to a power source and has a trigger switch and a secondary switch coupled in parallel to the trigger switch, the method comprising:
-
sensing actuation of the trigger switch;
reading a voltage from the trigger switch;
generating a first control signal if the voltage from the trigger switch is equal to or greater than a predetermined value;
sending the first control signal to a commutator to drive the electric motor in a first direction;
generating a second control signal if the voltage from the trigger switch is equal to or less than a predetermined cut-off value;
sending the second control signal to the commutator to drive the electric motor in a second direction, opposite the first direction, for a predetermined amount of time, and deactuating the secondary switch when the predetermined time has lapsed. - View Dependent Claims (17, 18, 19, 20, 21, 22)
-
-
23. An electric dispensing gun having a plunger, an electric motor, and a controller to automatically reverse the direction of plunger movement in the dispensing gun, the controller comprising:
-
a trigger switch capable of being coupled to a power source;
a power circuit coupled to the trigger switch, the power circuit having a secondary switch;
a programmable device coupled to the power circuit and trigger switch;
a commutator coupled to the programmable device and the power circuit; and
an overload sensor coupled to the programmable device and the power circuit and operable to produce an overload signal, the programmable device operable to sense actuation and deactuation of the trigger switch, and, upon sensing actuation of the trigger switch, to send a control signal to the commutator, and upon sensing deactuation of the trigger switch, to send a control signal to the commutator to reverse current flow therethrough for a predetermined amount of time, the programmable device further operable to deactuate the secondary switch when the predetermined time has lapsed, and to adjust the control signal if the overload signal exceeds a predetermined limit. - View Dependent Claims (24, 25, 26, 27, 28, 29, 30, 31, 32, 33)
-
Specification