US3078405A

US3078405A - Inverser switch

Info

Publication number: US3078405A
Application number: US11806A
Authority: US
Inventors: Jr Harry Stuart Tice
Original assignee: Controls Company of America
Current assignee: Controls Company of America
Priority date: 1960-02-29
Filing date: 1960-02-29
Publication date: 1963-02-19
Anticipated expiration: 1980-02-19

Description

H. S. TlCE, JR

INVERSER SWITCH Feb. 19, 1963 2 Sheets-Sheet 2 Filed Feb. 29. 1960 &

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INVENTOR. HARRY S. T\CE ,JR.

AT-roRNaY i nited This invention relates to an improved timer for washing mac tines or washerryer combinations, and particularly to a switch arrangement for controlling the direction of rotation of these devices.

This application is directed primarily to horizontal type washers, where interval timers are used to periodically reverse the direction of rotation of the drive motor for the washer during specific intervals in the program cycle. In washers of tln's type, continued rotation of the washer in one direct-ion is thought to produce twisting in the clothes, and by periodically reversing the direction of rotation of the washer, tendency of the clothes to become twisted will be reduced. Reversal at the end of each basic time interval is not considered satisfactory because the duration of the intervals is too long. To produce satisfactory results, reversal must occur periodically at intervals of a duration less than provided in the basic timer.

The primary object of the present invention is to provide a switching mechanism which can be used to periodically reverse the direction of rotation of a washer independently of the interval timer.

Another object is to provide a reversing switch mechanism which can be easily integrated into: an interval timer.

A further object is to provide a switch mechanism for a washer motor which can be readily adapted to washers already on the market.

A further object is to provide a switching mechanism which is simple in construction and operation, resulting in substantial manufacturing economies.

Other objects and advantages will be pointed out in, or be apparent from the specification and claims, as will obvious modifications of the two embodiments shown in the drawings in which:

FIG. 1 is a plane view of the switch mechanism with the cover removed.

2 is taken on line 22 of FIG. 1 showing the cam and slider arrangement.

FIG. 3 is taken on line 3-3 of FIG. 2 showing a partial section of the slider-switch arrangement.

FIG. 4 is a partial view of the slider-switch-ca1n arrangenrent.

FIG. 5 is a circuit diagram for an independent switching arrangement.

FIG. 6 is a side elevation of a timer with the switch mechanism incorporated in the ratchet drive.

FIG. 7 is taken on line 7--7 of FIG. 6, showing the switch arrangement.

PKG. 8 shows a circuit diagram for a drive motor.

As seen in the drawings, the switching mechanism includes a base plate it? which carries a number of single pole

double throw switches

12, 14 and M enclosed within cover 11. The switches are biased into engagement with one set of contacts and are moved into engagement with a second set of contacts by slider 18. The bias of the switches is used to hold the slider in position for cam foltates Fates-rt Patented Feb. lb, 1933 lower 26} to follow the peripheral cam surface of cam 22 mounted on motor shaft 24 and driven by timing motor 26.

The slider is positioned to slide on the surface of the base plate and is provided with

arms

27, 27 having dimples 23 riding on the surface of the base to stabilize the movement of the slider to reduce the friction between the slider and the plate. The slider is limited to linear motion by boss 31; and U shaped bracket 34, which engage slot 32 and motor shaft 24, respectively. The blades A, B and C of the switches are leaf springs secured to fixed terminals 36, 33 and iii and biased upwardly to engage

contacts

32, 44 and 45. The blades engage actuators d3, Si and 52, biasing the slider in an upper position as seen in FIGS. 1 and 3, and also holding the slider against the face of the plate. Cam follower 20 (comprising an extension of actuator 5%) is shown opposite cam surface 54, but does not engage this surface, so that the blades positively engage the contacts, thus insuring adequate contact pressure. On clockwise rotation of the cam, the cam fol-lower will ride up cam surface 56, moving the slider downward with the blades moved to a neutral or open position between the contacts. The cam follower will then ride up on cam surface 5% with the slider moving the blades into engagement with lower contacts 4 62 and o l. Continued rotation will reverse the cycle. The switch actuators on the slider can be designed so that actuator 48 opens switch 16 before switches l2 and 14 are opened, and closes switch in after

switches

12 and 14 are closed as required in certain induction motor circuits. The cam is designed to allow the contacts to be closed for twelve seconds, and retained in a neutral position for three seconds for a timing speed of one rpm. The cam surface can be cut to provide any cycle required for a particular device.

The device described above may control the direction of rotation of the drive motor by merely connecting the switches in the drive motor circuit as indicated in H6. 5. Terminals 66 and 63 are connected across the line L1, L2 and the start winding is connected to terminals it? and '72. The timer motor is connected in parallel with the start winding as shown, and the run winding is connected across terminals 36 and The blades are moved from one set of contacts to the other to reverse the direction of current flow through the star winding. A three second delay is provided in the cam to allow the drive motor to slow down before the current is reversed, to prevent an excessive surge current from being applied to the switch contacts, and so any centrifugally operated switches may reset.

It should be obvious that the time required to fabricate this device is reduced to a minimum because the slider requires no special assembling procedure, but is merely placed in position on the end plate and retained there by the switch blades.

In integrating this reversing switch arrangement into a washer or washer-dryer combination, it is only necessary to connect the reversing switches into the program switch circuit for the washer drive motor, so that the reversing switches are only operative when the program switch is active and can be by-passed when reversing is not desired. The simplicity of this circuit connection makes the reversing switch device readily adaptable to washers and washerdryers now on the market.

in F168. 6, "l and 8, the switch mechanism is integrated into a basic interval timer having a pair of

terminal boards

89 and 62, which carry program switches generally designated at 34. The terminal boards are carried between

end plates

86, 83 and the switches are provided with cam followers (actually switch blades) which act on cams 9% carried on arbor The arbor is journaled in the end plates for rotation and carries drive ratchet 94 which is adapted to receive impulses from the timer motor 96 through drive mechanism 98. The timer motor drives motor shaft lttt), on which molded disc 132 is secured for rotation. Stepping cam M4 is secured to one side of the disc, and is used as is customary, to build up energy in the drive mechanism, and at its drop permits a rapid delivery of the energy through the drive mechanism to the arbor. Lever 106 is pivoted on post 108 and biased by spring 110 to force follower 112 into engagement with the stepping cam. Verge 114 is pivoted on the lever and is biased by spring 116 into engagement with drive ratchet 94. As cam 104 rotates, the lever will rotate clockwise against the bias of spring 110, moving the verge to the next tooth on the drive ratchet. When the follower reaches the drop portion of the cam, the lever will rotate rapidly counterclockwise, forcing the verge against the drive ratchet to advance the arbor one step. Pawl 128 is pivoted on the end plate and biased by spring 129 into engagement with the drive ratchet to prevent reverse rotation of the arbor when the verge is being advanced to the next tooth on the drive ratchet.

The reversing switch mechanism is incorporated in housing 120 with cam 122 secured to the back of disc 102 and engaged by cam follower 123 on slider 124, which is positioned to slide on housing 126. Switch

actuators

128, 130 and 132 engage switch blades A, B and C on switches 13 i, 136 and 138, which are biased into engagement with

contacts

140, 142 and 144 and hold the slider in position for the cam follower to ride on the periphery of cam 122. On rotation of the cam, the slider will move the blades into engagement with

contacts

142, 146 and 143. This structure is similar to and operates the same as that described above.

The switch mechanism is connected into the circuit for the drive motor for the washer as shown in FIG. 8.

Program switches

83, 85 and 87 are used to by-

pass switches

134, 136 and 138 where unidirectional rotation is required during either the spin cycle or the drying cycle. In these instances, it is important to have the direction of rotation of the drive motor, as controlled by the switching mechanism, synchronized with the program switches, so that the drive motor is not rotating in one direction when the program switches call for another direction, producing an excessive torque on the drive motor. This can be accomplished when cams 16dand 122 are secured to disc 102 by aligning the drop portion of cam 104 with the cam surface on cam 122, which provides the same direction of rotation as controlled by the program switches.

This structure utilizes a single timer motor to operate both the interval timer and the switching mechanism with a relatively small increase in load on the timer. It is also possible to synchronize the program switches with the reversing switch mechanism to eliminate the production of excessive torque in the drive motor due to sudden reversals in the direction of rotation.

Although but two embodiments of the present invention have been shown and described, it will be apparent to those skilled in the art that changes and modifications may be made therein without departing from the spirit of the invention or from the scope of the appended claims.

I claim:

1. A switch device comprising, a motor, a cam driven by the motor, a cam follower confined to reciprocal motion in a plane parallel to the plane or the cam, switch means of the single blade double throw type, the blade of said switch means acting on the follower to bias the follower into engagement with the peripheral edge of the cam, said blade being actuated by the reciprocal motion of the follower, the cam being formed to hold the blades in one operative position or the other operative position and to delay the movement of the blade from one position to the other for a predetermined period of time.

2. A device according to claim 1 wherein the cam follower includes means for limiting the movement of the cam follower to linear motion.

3. A device according to claim 2 including a base on which the cam follower linearly reciprocates, the blade acting to retain the follower on the base.

4. The combination with a washing machine having a .drive motor and a timer of the type having-a cam bank driven through a drive mechanism by a timing motor in a step-by-step manner with the cam bank operating function switches according to a prescribed sequence, said drive motor being connected in circuit with certain of said function switches, for rotation in one direction when the circuit is closed, of means for controlling the direction of rotation of the drive motor comprising, reversing switch means connected in circuit with the drive motor, means for energizing the circuit including the reversing switches and the drive motor when said circuit through the function switches and the drive motor is open, drive means for actuating the switch means including a cam rotated by the drive means and a follower limited to linear motion in a plane parallel to the plane of the cam, said switch means biasing the follower into engagement with the peripheral edge of the cam so that the linear motion of the cam actuates the switches in a predetermined sequence to periodically reverse the direction of current flow and hence rotation of the drive motor. 5. The combination with a washing machine having a drive motor and a timer of the type having a cam bank driven through a drive mechanism by a timing motor in a step-by-step manner with the cam bank operating function switches according to a prescribed sequence, said drive motor being connected in circuit with certain of said function switches for rotation in one direction when the circuit is closed, of means for controlling the direction of rotation of the drive motor comprising, reversing switch means connected in the circuit for the drive motor, means for engaging the circuit including the reversing switches and the drive motor when said circuit through the function switches and the drive motor is open, a motor means, a cam rotated by the motor means, slider means confined to reciprocal motion, said switch means biasing the slider means into engagement with the cam, said switch means being actuated by the reciprocal motion of the slider means to periodically reverse the direction of current flow and hence rotation of the drive motor.

6. The combination according to claim 5 wherein the cam is formed to hold the reversing switch means in a neutral position with the circuit including the reversing switch means and the drive motor open to allow the drive motor to slow down before the current to the drive motor is reversed.

7. The combination with a sequence timer of the type having a plurality of function controlling switches operated by a cam bank driven at timing speed by a motor through a drive mechanism including a member rotating at a speed greater than timing speed, the timing speed of the cam bank causing sequential operation of the switches at predetermined intervals, of means for providing additional functions during said intervals comprising, a cam rotating with said member at a speed greater than timing speed, slider means confined to reciprocal motion, switch means including single blade double throw switches, the blades of the switch means biasing the slider into engagement with the cam so the slider reciprocates on rotation of the cam, said switch means being actuated by the motion of the slider, and circuit means connecting the reversing means with the function switches to increase the functions available during each interval of the timer.

8. The combination according to claim 7 including a base on which the slider reciprocates, the blades acting to retain the slider in position on the base for actuation by the cam.

9. The combination acconding to claim 8 wherein the slider means includes means for limiting its movement 10 to linear motion.

6 10. The combination according to claim 9 wherein the cam is provided with a three level cam periphery so that the switch means is cyclically moved from one position to another with a predetermined time delay in the move ment between positions.

References Cited in the file of this patent UNITED STATES PATENTS

Claims

1. A SWITCH DEVICE COMPRISING, A MOTOR, A CAM DRIVEN BY THE MOTOR, A CAM FOLLOWER CONFINED TO RECIPROCAL MOTION IN A PLANE PARALLEL TO THE PLANE OF THE CAM, SWITCH MEANS OF THE SINGLE BLADE DOUBLE THROW TYPE, THE BLADE OF SAID SWITCH MEANS ACTING ON THE FOLLOWER TO BIAS THE FOLLOWER INTO ENGAGEMENT WITH THE PERIPHERAL EDGE OF THE CAM, SAID BLADE BEING ACTUATED BY THE RECIPROCAL MOTION OF THE FOLLOWER, THE CAM BEING FORMED TO HOLD THE BLADES IN ONE OPERATIVE POSITION OR THE OTHER OPERATIVE POSITION AND TO DELAY THE MOVEMENT OF THE BLADE FROM ONE POSITION TO THE OTHER FOR A PREDETERMINED PERIOD OF TIME.