Wiper-washer circuit arrangement

Claim 2

In a wiper-washer arrangement, particularly an arrangement for wiping and washing the front of a vehicle headlight, a vehicle windshield or the like, in combination, an electric wiper motor for driving a wiper, having first and second wiper motor terminals; a switch device comprising a switch contact electrically connected to said first wiper motor terminal, a work contact and a rest contact, and further including switching means mechanically coupled to and driven by said wiper motor and operative for causing said switch contact to alternately come into electrical engagement with said work contact and said rest contact; a source of electrical energy having first and second source terminals; means for connecting said first and second wiper motor terminals to said first and second source terminals, respectively, to establish a principal motor current path for the flow of wiper motor drive current, and including means for interrupting said principal motor current path; an electric pump motor for driving a pump which discharges a washing fluid onto the surface to be washed, having first and second pump motor terminals; means connecting said first source terminal to said work contact for establishing an auxiliary current path for the flow of wiper motor drive current when said switch contact is in electrical engagement with said work contact; and means connecting said first pump motor terminal to said rest contact and said second pump motor terminal to said second source terminal, for establishing a braking current path for the flow of wiper motor braking current through said pump motor when said switch contact is in electrical engagement with said rest contact and said principal motor current path is in interrupted condition.

Claim 3

The arrangement defined in claim 1, wherein said switching means comprises a rotating switching disk driven by said wiper motor and in engagement with said contacts and operative for establishing electrical engagement between said switch contact and said work contact as said disk turns through an angle greater than 90* and operative for establishing electrical engagement between said switch contact and said rest contact during the remainder of one rotation of the switching disk.

Claim 4

The arrangement defined in claim 2, wherein said angle is 100*.

Claim 5

The arrangement defined in claim 1, wherein said means for interrupting said principal motor current path includes a pulse-generating circuit stage comprised of an output transistor having an emitter-collector path, a relay winding connected in series with said emitter-collector path, and a relay switch which closes when said relay winding becomes energized connected in said principal motor current path and a manually activatable switch connected in said principal motor current path, and further including means for controlling the energization of said relay winding in dependence upon the operation of said switch device.

Claim 6

The arrangement defined In claim 4, wherein said means for controlling the energization of said relay winding comprises means for applying to the base of said transistor a voltage derived from a circuit junction connected in said principal motor current path intermediate said first source terminal and said relay switch.

Claim 7

The arrangement defined in claim 5, wherein said means for controlling the energization of said relay winding further includes a diode connected in said principal motor current path intermediate said first source terminal and said relay switch and means for applying across the base-emitter junction of said transistor the voltage drop across said diode.

Claim 8

In a wiper-washer arrangement, particularly an arrangement for wiping and washing the front of a vehicle headlight, a vehicle windshield, or the like, in combination, a first and a second electric wiper motor for driving a first and a second wiper, respectively, each of said motors having respective first and second motor terminals; first and second switch devices, each comprising a switch contact electrically connected to the first motor terminal of a respective one of said motors, a work contact and a rest contact, and each switch device further including switching means mechanically coupled to and driven by a respective one of said motors and operative for causing the associated switch contact to alternately come into electrical engagement with the associated work contact and the associated rest contact; a source of electrical energy having first and second source terminals; means for connecting said first and second motor terminals of each of said motors to said first and second source terminals, respectively, to establish first and second principal motor current paths for the flow of wiper motor drive current through said first and second motors, respectively, and including means for interrupting said principal motor current paths; an electric pump motor for driving a pump which discharges a washing fluid onto the surfaces to be washed by the wipers driven by said wiper motors, said electric pump motor having first and second pump motor terminals; means connecting said first source terminal to the work contact of each of said switch devices for establishing first and second auxiliary current paths for the flow of drive current through said first and second wiper motors, respectively, when the respective switch contacts are in electrical engagement with the respective work contacts; and means electrically connecting said first pump motor terminal to both said rest contacts and connecting said second pump motor terminal to said second source terminal, for establishing a braking current path for the flow of wiper motor braking current through said pump motor when said switch contacts are in electrical engagement with said rest contacts and said principal motor current paths are in interrupted condition, and further including first and second diodes respectively connected in said first and second principal motor current paths for preventing energization of each of said wiper motors by current flowing through the auxiliary current path associated with the other one of said wiper motors.

Claim 9

In a wiper-washer arrangement, particularly an arrangement for wiping and washing the front of a vehicle headlight, a vehicle windshield, or the like, in combination, a first and a second electric wiper motor for driving a first and a second wiper, respectively, each of said motors having respective first and second motor terminals; first and second switch devices, each comprising a switch contact electrically connected to the first motor terminal of a respective one of said motors, a work contact and a rest contact, and each switch device further including switching means mechanically coupled to and driven by a respective one of said motors and operative for causing the associated switch contact to alternately come into electrical engagement with the associated work contact and the associated rest contact; a source of electrical energy having first and second source terminals; means for connecting said first and second motor terminals of each of said motors to said first and second source terminals, respectively, to establish first and second principal motor current paths for the flow of wiper motor drive current through said first and second motors, respectively, and including means for interrupting said principal motor current paths; an electric pump motor for driving a pump which discharges a washing fluid onto the surfaces to be washed by the wipers driven by said wiper motors, said electric pump motor having first and second pump motor terminals; means connecting said first source terminal to the work contact of each of said switch devices for establishing first and second auxiliary current paths for the flow of drive current through said first and second wiper motors, respectively, when the respective switch contacts are in electrical engagement with the respective work contacts; and means electrically connecting said first pump motor terminal to both said rest contacts and connecting said second pump motor terminal to said second source terminal, for establishing a braking current path for the flow of wiper motor braking current through said pump motor when said switch contacts are in electrical engagement with said rest contacts and said principal motor current paths are in interrupted condition, and further including first and second diodes respectively connected in said first and second principal motor current paths for preventing energization of each of said wiper motors by current flowing through the auxiliary current path associated with the other one of said wiper motors.