US2992448A - Electric switches - Google Patents

Description

July 18, 1961 w. E. SIMPSON 2,992,448

ELECTRIC SWITCHES Filed Aug. 28, 1957 2 Sheets-Sheet 1 49 [0 ia-L 5 INVENTOR.

gi/z'zam f. Simpson a/Krmg HIS ATTORNEY July 18, 1961 slMpsoN 2,992,448

ELECTRIC SWITCHES Filed Aug. 28, 1957 2 Sheets-Sheet 2 IN V EN TOR.

[Mi/{122222 [I Sim v50)? BY ms ATTORNEY Patented July 18, 1961 2,992,448 ELECTRIC SWITCHES William E. Simpson, Mill Hill, London, England, assignor to General Motors Corporation, Detroit, Mich., a corporation of Delaware Filed Aug. 28, 1957, Ser. No. 680,826 Claims priority, application Great Britain, Sept. 6, 1956 9 Claims. (Cl. 15-250.)2)

This invention relates to electric switches designed to effect the control of either of two devices, without affecting the other, by a single control member and to windscreen cleaner installations in which such switches are used.

An electrieswiteh mechanism according to the invention has a frame in which a rotatable actuator spindle is axially movable to vcontrol one device, a movable contact rotatable with but movable axially on the spindle, and a spring which forces the movable contact towards a fixed contact supported by the frame so that rotation of the spindle, by bringing the movable and fixed contacts into and out of engagement, can control another device.

Advantageously the actuator spindle has, at one end a manual control knob, and, at the other end, a latch which limits axial movement of the spindle in the direction of the knob.

Preferably the frame has a pair of resiliently engaged fixed contacts and the movable contact is rotatable by the actuator spindle into a first position completely disengaged from the fixed contacts; into a second position in which it engages a fixed contact but does not disengage the fixed contacts from each other; and into a third position in which it engages said fixed contact and also disengages the fixed contacts from each other.

By means of such a switch mechanism a circuit for the electric motor of a windscreen wiper can be controlled so as to disconnect the motor from its current source or operate it at high or low speed; and a windscreen washer pump can be actuated by axial movement of the spindle irrespective of the angular position of the movable contact.

The scope of the invention is defined by the appended claims; and how it may be performed is hereinafter particularly described with reference to the accompanying drawings in which:

FIGURE 1 is a plan elevation of a switch mechanism according to this invention showing the spindle in its two axial positions.

FIGURE 2 is a side elevation of the switch mechanism with certain parts broken away in combination with a washer pump shown partly in section, on a smaller scale than shown in FIGURE 1.

FIGURES 3, 4 and 5 are circuit diagrams of the wiper motor controlled by the switch.

FIGURE 6 is a side elevation of the switch shown in FIGURE 1.

FIGURE 7 is a sectional view taken along line 77 of FIGURE 6.

FIGURES 8 and 9 are, respectively, views in elevation, of a two-part modified coupling shown on a larger scale for the switch of FIGURE 1.

The switch mechanism (FIGURES 1, 6 and 7) is arranged in a frame 10 having substantially the shape of a letter 0, two parallel arms 11 and 12 of the frame being connected by an integral member 13 at right angles to each of the arms. Mounted in the frame parallel to the arm 12 is a plate 14 of insulating material formed with an opening. The integral member 13 of the frame has two openings 15 in which projections 16 on the plate 14 fit; and the arm 12 has two inwardly turned lugs 17 which engage shoulders at the bottom of the plate '14.

The arm 11 of the frame has an inturned internally threaded flange 18 into which a journal bearing 19 (FIG- URE 6) for an actuator spindle 20 is screwed. The actuator spindle extends through the bearing 19, the hole in the insulator plate 14, and an opening in the arm 12 of the frame. A control knob 21 is mounted on the end of the spindle adjacent the bearing 19.

Slidably mounted on the spindle 20 but rotatable therewith by means of a flat on the spindle is a coupling 22 having two integral ears 23 which enter openings 24 in a movable contact 25. The movable contact is also slidable on the spindle and is urged towards the coupling 22 by a helical spring 26 which at one end, fits around the flange 18 and, at the other end, bears against the contact 25. The spring 26 thus both holds the insulator plate 14 firmly in position in the frame 10 and keeps the ears 23 on the coupling 22 engaged in the openings 24 in the contact 25 so that the contact 25 rotates with the spindle. The hole in the contact 25 through which the spindle 20 passes is slightly larger than the diameter of the spindle so that the contact 25, in addition to being able to move axially relatively to the spindle, can also rock slightly relatively to it.

The contact 25 has two diametrically opposed radial projections 27 and 28; the projection 27 is adapted to engage one of two fixed contacts 29 and 30 which are secured to the insulator plate 14 and the other projection 28 is adapted to ride on an arcuate metal strip 31 which is also secured to the insulator plate 14 and has at either end abutment lugs 32 which form stops to limit the rotation of the contact 25 in either direction. The arcuate strip 31 is also formed with three grooves therein so as to positively locate the movable contact in any one of three positions of angular movement corresponding to an off position and to positions (A, F) of engagement with one of the fixed contacts: the slight rocking permitted the contact '25 relatively to the spindle 20 allows the projection 28 to ride into and out of the grooves and the projection 27 simultaneously to maintain contact with the insulator plate 14 or one of the fixed contacts 29, 30.

The fixed contact 29 is a resilient strip which is normally urged into engagement with the other fixed contact 30 and in one angular position (F) of the movable contact 25 the resilient strip 29 is adapted to be depressed, by the movable contact 25, out of engagement with the other fixed contact 30.

The end 34 of the actuator spindle 20 which extends through the arm 12 of the frame is formed with a peripheral groove 35, and a latch lever 36 has an opening by which it can be passed over the end 34 of the actuator spindle and into engagement in the peripheral groove 35. One end 38 of the latch lever is engaged in an opening in an up-turned lug 39 on the arm 12 and has mounted thereon a helical spring 40 which fits around a reduced portion 41 of the lever and abuts at one end against the up-turned lug 39 and at the other end against a shoulder 42 on the lever 36. The spring 40 thus biases the lever 36 in one direction to maintain it in its latched condition on the spindle, so that the lever limits axial movement of the spindle 20 to the right.

The switch mechanism just described is capable of operating one device by axial movement of the spindle, and another device by rotary movement of the spindle. Despite the fact that it can operate the devices separately or simultaneously it is simple, reliable, and easy to manufacture and assemble. Assembly merely involves fitting the insulator plate 14 in the frame 10, screwing the bearing 19 into the arm 11, passing the actuator spindle 20 through the bearing 19, spring 26, contact 25, coupling 22 and holes in the plate 14 and arm 12, care being taken to ensure that the ears 23 on the coupling are aligned with the openings 24 in the contact 25. The spring then forces the contact 25 and coupling 22 against the insulator plate 14 so that the ears 23 enter the openings 24 to couple the contact 25 to the spindle 20, and in so doing holds the plate 14 in its mounting in the frame. The latch lever 36 then engages the peripheral groove 35 in the spindle to limit the latters axial movement to the right.

FIGURE 2 shows how the switch mechanism just described can be arranged to form part of a Windscreen cleaner installation, which includes a windscreen washer and windscreen wiper.

The bearing '19 for the actuator spindle 20 has a flange 44 which, when the bearing is screwed into the interned flange 18 in the arm 11 of the frame, engages the external surface of the facia panel 49 of a motor vehicle to hold the switch mechanism in position on the inner surface of the panel.

An L-shaped bracket 45, fixed to the integral member 13 of the frame, carries a washer pump 46. The pump itself is of conventional design and comprises a spring biased plunger 47 and a plunger rod 48. The left hand end 34 of the spindle 20 is locked to the plunger rod 48 by a sleeve coupling 50. Thus as the control knob 21 is pulled to the right, the pump plunger 47 draws in liquid and when the knob is released the plunger spring moves the plunger to the left to direct a jet of liquid onto the windscreen through a pipe 51.

The circuit arrangement for the motor of the windscreen wiper motor is shown diagrammatically in FIG- URES 3 to 5, the reference numerals in these figures referring to the same parts as in FIGURES 1, 6 and 7.

The circuit includes a battery 53, which is earthed at 54, a series field winding 55, the windscreen wiper motor armature 56, the fixed contact 29 which has (FIG- URE 1) a terminal 57 connected thereto, the projection 27 of the movable contact 25, and the actuator spindle 20 which is earthed at 58 via a terminal 59 (FIGURE 1). In parallel with the motor armature 56 is a shunt field winding 60, resistance 61, and a circuit 62. When the fixed contacts 29 and 30 are in engagement the circuit 62 is completed and the resistance 61 is short circuited. The fixed contact 30 is connected to a terminal 63 (FIGURE 1).

When the contact 25 is in the position shown in FIG- URES 6 and 7, the circuit to the motor 56 is not made. When the spindle 20 is rotated to bring the contact 25 into position A (FIGURES 4 and 7), the resistance 61 is short circuited by the circuit 62 so that the motor 56 operates at slow speed. And when the actuator spindle is rotated to bring the movable contact 25 into the position F in FIGURES and 7, the left hand end of the fixed contact 29 is depressed to move it out of engagement with the contact 30. This opens the circuit 62 so that the resistance 61 forms an effective part of the circuit of the shunt field 61, and the motor 56 therefore operates at a higher speed.

In a modification, shown in FIGURES 8 and 9, of the switch mechanism shown in FJGURES 1, 6 and 7, a two part coupling 68 is used to couple the movable contact 25 to the actuator spindle 20. One part 64 of the coupling has, as before, ears 69 but the hole therein through which the spindle 20 passes is not shaped to correspond to the flat on the spindle. Thus the part 64 can rotate relatively to the spindle. The other part 65 of the coupling is disposed between the part 64 and the contact 25, and has a hole through which the spindle 20 passes such that the flat on the spindle engages the edges thereof. The ears 69 project through slots '70 in the periphery of the part 65 into the openings 24 in the contact 25. Thus when the actuator spindle 20 is rotated, the edges of the slots 70 engage the ears 69 so that both the contact 25 and the part 64 of the coupling also rotate.

Thus in any of the three positions of angular movement of the rotary contact 25 the actuator spindle 20 can be moved axially to control the windscreen washer pump, and in this way the windscreen washer can be actuated, regardless of whether the windscreen wiper motor 56 is operating at low or high speed or is switched off by the employment of a single control knob 21 which also controls the operation of the windscreen wiper motor.

I claim:

1. An electric switch mechanism for selectively controlling two devices separately or simultaneously comprising a frame, an actuator spindle rotatably and axially movable in said frame, a movable contact mounted on said actuator spindle, said movable contact being movable axially and rockable slightly on said actuator spindle, a coupling connecting said movable contact to said spindle so that it rotates therewith, a pair of resiliently engaged fixed contacts mounted on an insulator plate supported in said frame, a spring which forces said movable contact towards said fixed contacts and thereby holds said insulator plate in position, a control knob mounted at one end of said spindle and a latch at the other end of said spindle to limit movement thereof in one direction, said latch comprising an apertured lever pivoted in said frame through which said spindle extends and which is spring biassed so that an edge of said aperture engages in a groove in said spindle, said actuator spindle being movable axially to control said one device and rotatably to control said other device by bringing said movable contact into a first position completely disengaged from said fixed contacts, a second position in which it engages but does not disengage said fixed contacts from each other, and a third position in which it engages one of said fixed contacts and disengages said fixed contacts from each other,

2. An electric switch mechanism for selectively controlling two devices separately or simultaneously comprising a frame, an actuator spindle rotatably and axially movable in said frame, a movable contact mounted on said actuator spindle, said movable contact being rotatable with but movable axially on said actuator spindle, a pair of resiliently engaged fixed contacts mounted on an insulator plate supported in said frame, a spring which forces said movable contact towards said fixed contacts and thereby holds said insulator plate in position, a control knob mounted at one end of said spindle and a latch at the other end of said spindle to limit axial movement thereof in one direction, said actuator spindle being movable axially to control said one device and rotatably to control said other device by bringing said movable contact into a first position completely disengaged from said fixed contacts, a second position in which it engages but does not disengage said fixed contacts from each other, and a third position in which it engages one of said fixed contacts and disengages said fixed contacts from each other.

3. An electric switch mechanism for selectively controlling two devices separately or simultaneously, comprising a frame, an actuator spindle rotatably and axially movable in said frame, a movable contact mounted on said actuator spindle, said movable contact being rotatable with but movable axially on said actuator spindle, a pair of resiliently engaged fixed contacts supported by said frame, a control knob mounted at one end of said spindle and a latch on the other end of said spindle to limit axial movement thereof in one direction, said actuator spindle being movable axially to control said one device and rotatably to control said other device by bringing said movable contact into a first position completely disengaged from said fixed contacts, a second position in which it engages but does not disengage said fixed contacts from each other, and a third position in which it engages one of said fixed contacts and disengages said fixed contacts from each other.

4. An electric switch mechanism for selectively controlling two devices separately or simultaneously, comprising a frame, an actuator spindle rotatably and axially movable in said frame, a movable contact mounted on said actuator spindle, said movable contact being rotatable with but movable axially on said actuator spindle, and a pair of resiliently engaged fixed contacts supported by said frame, said actuator spindle being movable axially to control said one device and rotatably to control said other device by bringing said movable contact into a first position completely disengaged from said fixed contacts, a second position in which it engages but does not disengage said fixed contacts from each other, and a third position in which it engages one of said fixed contacts and disengages said fixed contacts from each other.

5. An electric switch mechanism for selectively controlling two devices separately or simultaneously comprising a frame, an actuator spindle rotatably and axially movable in said frame, a movable contact mounted on said actuator spindle, said movable contact being rotatable with but movable axially on said actuator spindle, a pair of resiliently engaged fixed contacts supported by said frame, a spring which forces said movable contact towards said fixed contacts, a control knob mounted at one end of said spindle and a latch at the other end of said spindle to limit axial movement thereof in one direction, said latch comprising an apertured lever pivoted in said frame through which said spindle extends and which is spring-biassed so that an edge of said aperture engages in a groove in said spindle, said actuator spindle being movable axially to control said one device and rotatably to control said other device by bringing said movable contact into a first position completely disengaged from said fixed contacts, a second position in which it engages but does not disengage said fixed contacts from each other, and a third position in which it engages one of said fixed contacts and disengages said fixed contacts from each other.

6. An electric switch mechanism for selectively controlling two devices separately or simultaneously, comprising a frame, an actuator spindle rotatably and axially movable in said frame, a movable contact mounted on said actuator spindle, said movable contact being rotatable with but movable axially on said actuator spindle, a pair of resiliently engaged fixed contacts mounted on an insulator plate supported in said frame, a spring which forces said movable contact towards said fixed contacts and thereby holds said insulator plate in position, said actuator spindle being movable axially to control said one device and rotatably to control said other device by bringing said movable contact into a first position completely disengaged from said fixed contacts, a second position in which it engages but does not disengage said fixed contacts from each other, and a third position in which it engages one of said fixed contacts and disengages said fixed contacts from each other.

7. A motor vehicle windscreen cleaner installation comprising an electric windscreen wiper motor, said motor including a shunt field circuit with a resistance in series therewith, a windscreen washer pump and an electric switch mechanism for selectively controlling said motor and said pump simultaneously or separately, said mechanism comprising a frame, an actuator spindle rotatably and axially movable in said frame, a movable contact mounted on said actuator spindle, said movable contact being rotatable with but movable axially on said actuator spindle, a pair of resiliently engaged fixed contacts supported by said frame, said actuator spindle being movable axially to control said pump and rotatably to control said motor by bringing said movable contact into a first position completely disengaged from said fixed contacts, a second position in which it engages but does not disengage said fixed contacts from each other and thereby short circuits said resistance in said shunt field circuit of said motor, and a third position in which it engages one of said fixed contacts and disengages said fixed contacts from each other so that said resistance is in the shunt field circuit of said motor.

8. A motor vehicle windscreen cleaner installation comprising an electric windscreen wiper motor, said motor including a shunt field circuit with a resistance in series therewith, a windscreen washer pump and an electric switch mechanism for selectively controlling said motor and said pump simultaneously or separately, said mechanism comprising a frame, an actuator spindle rotatably and axially movable in said frame, a movable contact mounted on said actuator spindle, said movable contact being rotatable with but movable axially on said actuator spindle, a pair of resiliently engaged fixed contacts mounted on an insulator plate supported in said frame, a spring which forces said movable contact towards said fixed contacts and thereby holds said plate in position, a control knob mounted at one end of said spindle and a latch at the other end of said spindle to limit movement thereof in one direction, said actuator spindle being movable axially to control said one device and rotatably to control said other device by bringing said movable contact into a first position completely disengaged from said fixed contacts, a second position in which it engages but does not disengage said fixed contacts from each other, and a third position in which it engages one of said fixed contacts and disengages said fixed contacts from each other.

9. A motor vehicle windscreen cleaner installation comprising an electric windscreen wiper motor, a windscreen washer pump and an electric switch mechanism for selectively controlling said motor and said pump simultaneously or separately, said mechanism comprising a frame, an actuator spindle rotatably and axially movable in said frame, a movable contact mounted on said actuator spindle, said movable contact being movable axially on said actuator spindle, a coupling connecting said movable contact to said spindle so that it rotates therewith, a fixed contact mounted on an insulator plate supported in said frame, a spring which forces said movable contact towards said fixed contact and thereby holds said insulator plate in position, a control knob mounted at one end of said spindle and a latch at the other end of said spindle to limit movement thereof in one direction, said latch comprising an apertured lever pivoted in said frame through which said spindle extends and which is spring biassed so that an edge of said aperture engages in a groove in said spindle, said actuator spindle being movable axially to control said pump and rotatably to control said motor by bringing said movable contact into and out of engagement with said fixed contact.

References Cited in the file of this patent UNITED STATES PATENTS 2,252,489 Bluemle Aug. 12, 1941 2,263,754 Batcheller Nov. 25, 1941 2,499,298 Christensen Feb. 28, 1950 2,816,316 Oishei Dec. 17, 1957

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