Patent GB-757231-A (GB)
Title: Improvements in or relating to a windshield washer
IPC: B60S1/50
Filed: 1953-12-02
Abstract: 757,231. Windscreen washers. TRICO PRODUCTS CORPORATION. Dec. 2, 1953 (Dec. 3, 1952], No. 33517/53. Class 138(1) [Also in Group XXVIII] A windscreen washer has a suction operated fluid-pressure motor, a liquid pump operated by the motor, a control valve for the motor and an electromagnet having an armature operable to open the valve and connect the motor to the source of suction. The washer unit, Fig. 2, comprises a liquid reservoir 9, supported in a vehicle by a bracket 66, a motor chamber 13 carried by the cover 10 of the reservoir, a control unit 39, 40, for the motor, a pump chamber 14 carried by the motor chamber and a cap section 21 carried by the bottom of the pump chamber. A flange 15 on the pump chamber 14 has radial lugs engaging in recesses 18 between radial lugs 16 on the bottom of the motor chamber 13, and overhanging a split spring ring 19 which thus detachably holds the pump chamber to the motor chamber. A piston 30 for the motor chamber is integral with the pump plunger 29. A spring 31 arranged between the plunger 29 and a wall 32 of the motor chamber effects the delivery stroke of the pump. The control unit Fig. 4 comprises a cover 40 and a base portion 39 having a nipple 43 connectible by tubing with the vehicle intake manifold and communicating with an annular passage 44 provided with a valve seat 45. Coaxial with the seat 45 is a valve seat 47 and a passage 48 interconnects the seats 45, 47. Valves 50 and 51 on the opposite ends of a stem 49 co-operate with the seats 45, 47, respectively, the valve unit 49, 50, 51 being urged upwardly to close the seat 45 by a spring 52. The valve seat 47 communicates with atmospheric vents 46 when the valve 51 is lifted. The electromagnet 54 is also carried in the base 39 and when momentarily energized its armature core 55<SP>1</SP> sharply strikes a pin 56 to move the valve unit 49, 50, 51 downwardly whereafter it is maintained by pressure differential. The armature core 55<SP>1</SP> is normally urged upwardly by a spring 57. A bleed hole 61 is provided in the valve 50 so that when the valve 50 is closed as shown in Fig. 4, the interior of the motor chamber is in communication with the passage 48 and vents 46. The cap section 21, Fig. 7, has a tube 22 open at its bottom end to the liquid in the reservoir and having a port 24 in its upper end, and an outlet nipple 8 connectible by a tube 7, Fig. 2 with a spray nozzle directed towards the windshield. The bottom wall 20 of the pump chamber has an outlet port 25 and inlet openings 24a and interposed between the wall 20 and the cap member 21 is a valve disc 23 provided with flap valves 28, 27, Fig. 10, co-operating with the ports 24, 25 respectively. Loosely mounted within the plunger 29 and within the spring 31 is a support 62, Fig. 2, carrying at its upper end a spring 60. Operation. The momentary energization of the electromagnet 54 causes the valve 51 to close the seat 47 and the valve 50 to open the seat 45. Fluid pressure is thus placed in communication with the motor chamber to lift the piston and plunger and to effect the intake stroke of the pump, at the end of the stroke the spring 60 being compressed and finally overcoming the pressure differential maintaining the valve 51 closed. As soon as the valve 51 opens the motor chamber on top of the piston 30 is placed in comunication with the atmosphere. The underside of the piston 30 is always maintained at atmospheric pressure through the interfitting lugs on the motor and pump chambers. The spring 31 then causes the piston and plunger to move downwardly and effect the pump delivery stroke. Specification 757,297 [Group XXVIII] is referred to. Reference has been directed by the Comptroller to Specification 662,241.