SWITCHABLE BLOWER MOTOR RESISTOR FOR HVAC APPLICATION
A low voltage range power switch is provided. The power switch includes a contact pin and at least two contact bushes. The contact pin has a longitudinal axis L and is arranged so as to be displaceable along a displacement path W in the direction of the longitudinal axis L. A graduated rotation speed adjuster having the power switch and a motor vehicle ventilation system including the graduated rotation speed adjuster are also provided.
1 .- 11 . (canceled)
12 . A low voltage range power switch, comprising:
a contact pin; and
at least two contact bushes;
wherein the contact bushes are adapted to receive the contact pin and form a high current-proof electrical contact.
13 . The power switch of claim 12 , wherein the contact pin has a longitudinal axis L and is displaceable along a displacement path W in the direction of the contact pin's longitudinal axis L.
14 . The power switch of claim 12 , wherein the contact bushes are disposed in a sequence along the displacement path W.
15 . The power switch according to claim 12 , wherein the contact pin has a copper-bearing core.
16 . The power switch according to claim 12 , wherein the contact pin has a substantially corrosion-resistant and abrasion-proof conductive coating deposited thereon.
17 . The power switch according to claim 12 , wherein the contact bush has a hyperbolic contact grid disposed in an interior of the contact bush.
18 . The power switch of claim 17 , wherein the hyperbolic contact grid is adapted to receive the contact pin and form a plurality of line contacts.
19 . The power switch according to claim 17 , wherein the hyperbolic contact grid has a core formed of a beryllium/copper alloy.
20 . The power switch according to claim 13 , wherein the contact pin is displaceable along the path W a manually actuated mechanical drive.
21 . The power switch according to claim 12 , further comprising an actuating element adapted for manual actuation.
22 . The power switch according to claim 21 , wherein the actuating element is in operative connection with a mechanical drive adapted to displace the contact pin.
23 . The power switch according to claim 12 , wherein the contact pin is displaceable by means of a mechanical drive operable by a motor.
24 . A graduated rotation speed adjuster for a low voltage electric motor, comprising:
a low voltage range power switch, including a contact pin, and at least two contact bushes, wherein the contact bushes are adapted to receive the contact pin and form a high current-proof electrical contact; and
at least one power resistance.
25 . The graduated rotation speed adjuster of claim 24 , wherein the power switch has at least three stages.
26 . The graduated rotation speed adjuster according to claim 24 , wherein the rotation speed adjuster has three switching states for the electric motor in electrical communication with an external voltage source via the rotation speed adjuster.
27 . The graduated rotation speed adjuster of claim 26 , wherein the three switching states include: a) an interrupted connection to the voltage source; b) a direct connection with the voltage source; and c) a connection with the voltage source via the power resistance connected in series.
28 . The graduated rotation speed adjuster according to claim 24 , wherein the power resistance includes a metallic resistance wire wound around an insulating base body and coated with an insulating layer.
29 . A motor vehicle ventilation system, comprising:
a low voltage electric motor adapted to power a fan; and
a graduated rotation speed adjuster, including an at least three-stage, low voltage range power switch and at least one power resistance, the power switch including a contact pin and at least two contact bushes, wherein the contact bushes are adapted to receive the contact pin and form a high current-proof electrical contact.
30 . The motor vehicle ventilation system of claim 29 , wherein the at least three-stage power switch and the at least one power resistance are disposed adjacent to each other and are in a heat exchange relationship with a stream of a cooling medium adapted to remove waste heat from the power resistance when the motor vehicle ventilation system is in operation.
31 . The motor vehicle ventilation system of claim 29 , further including a drive for the contact pin, wherein the drive is actuated by an actuating element disposed on the instrument panel of a motor vehicle.