United States Patent 3581028

An electrically powered liquidizer controlled by a timer-jogger switch means actuated by a lost motion between a manual control and a driven slip clutch member when the control is turned in one direction to energize the liquidizer and a timer drive member without relative lost motion, and turned in the opposite direction with lost motion to manually energize the liquidizer continuously or intermittently for a period of time which, at will, can be a long or momentary period of time. The control is resiliently held in OFF position against inadvertent movement.

Application Number:
Publication Date:
Filing Date:
Primary Class:
Other Classes:
74/568T, 200/283, 968/815
International Classes:
G04F3/06; (IPC1-7): H01H7/08; H01H43/10
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US Patent References:

Primary Examiner:
Schaefer, Robert K.
Assistant Examiner:
Scott J. R.
I claim

1. In combination with an electrical appliance having a motor and control panel:

2. The combination called for in claim 1 including a manually actuated means carried by the housing to close said switch while being manually held when said cam member is in OFF position.

3. The combination called for in claim 2 in which said manually actuated means includes a lever means, terminally engaging said first-mentioned switch.

4. The combination called for in claim 1 including a second switch connecting the timer motor in parallel with the motor of said appliance by said cam means when said knob member is moved in said one direction to close the first-mentioned switch.

5. In a food-processing appliance having a power motor and a timer motor, a time control for the motors comprising:

6. The combination called for in claim 5 in which the manual means includes a manual member carrying the said snap action means with a cam element engaging one of the contact elements to close said one of the switches by manual movement in one direction; and

7. The combination called for in claim 5 in which said snap action means includes:

8. The combination called for in claim 5 including a second manual mean for moving the two contact elements of the one switch relative to each other to close the switch while manually actuated.

9. The combination called for in claim 5 in which said snap action means includes a disc peripherally having a relief in the OFF position bordered by cams of different effective heights.

10. In a timer for electrical appliances:

11. The combination called for in claim 10 including a push button to close said switch by applied manual pressure when said cam means is in its resting position.

12. The combination called for in claim 10 in which said lost motion device includes a key means on one of the members alternatively engaging angularly spaced wall means on the other member.

13. The combination called for in claim 10 in which said cam member comprises a disc section peripherally having a cam relief in said resting position.

14. In combination with an electrical appliance powered by a universal motor, a timer switch therefor, comprising:

15. The combination called for in claim 14 in which said movable member comprises a disc having peripheral cam reliefs of different depths with the deepest one for OFF position intermediate the others and the highest cam relief engaged by said movement in said one direction.


Swanke and Raymond, application Ser. No. 813,957


With increasing knowledge and research in laboratories and in food and drink preparation, definiteness of timing, agitation speeds and volumes of ingredients have become increasingly important in recipes and formulas for desired optimum results when ingredients are being comminuted, mixed, homogenized or blended, generally referred to herein as liquidizing. Even then, variation in the quality of ingredients or local power voltages may vary the results expected and time corrections on the spot have to be made. Accordingly, although recipes are written with exact ingredients and quantities as guides for excellent constancy in the end results with particular mixing speeds and time increments, means is provided to reenergize the liquidizer momentarily if desired either to accomplish particular prescribed results or vary them in accordance with the whims of the operator.

For these purposes, inexpensive timers with excellent accuracy and operational characteristics for persons unskilled mechanically are greatly desired for liquidizers.

Heretofore timers have been provided which have a substantial degree of lost motion that is a part of the time increment being metered. This lost motion between two relatively movable members has been required and utilized to provide a snap turnoff switch action for switch contact life and it interferes with the accuracy and the setting of a short time period for food-handling, electrically powered household appliances. The lost motion either oversets the switch turnoff for short periods or the timer button has to be advanced and then retracted to approach a short period setting before the motor is turned on. Generally a timer driven element is manually advanced, followed spatially by a loose follower which holds the switch closed. The driven member runs for a period of time to take up the spatial lost motion before the timer follower is started on its return metering movement to a critical position where the switch is ready for release. Once the lost motion is recovered it is thereby reestablished in the follower and then after the final run down increment of movement, will utilize the lost motion for the snap action of the switch. As the switch begins to open upon release, the follower with its lost motion flips to permit a full snap throw opening movement for the switch.

At best the lost motion rundown is an undesirable time variable which burdens the system and creates an added increment of time before a switch opening can occur at any setting. Lost motion, however, may not be eliminated since it is required for the snap action of the switch. Therefore, although the rundown of the lost motion is an added increment of time and it is very difficult to operate the timer for short periods or quick bursts of motor energization, sometimes referred to as jogging, yet the lost motion is provided for a snap action switch opening.


In the present invention the snap action element is on the control indicia knob and it moves in one direction the distance of the lost motion between it and the slip clutch driven member before it directly closes the switch. Thereby, the lost motion is overcome before the time setting function is started. Accordingly, the control knob can be accurately set in one direction for an immediate run down in the opposite direction that is coincident with cutter operation. The time period will be accurately metered yet the snap action opening of the switch will still be provided by the lost motion being recovered by the control knob at the end of the timing cycle rather than at the start of the timer rundown.

Illustratively, a slip clutch carried by the low speed gear of an electric timer frictionally drives a driven member which has a rotary drive element such as a crank pin or a shoulder on it. The manually set knob has a rotationally driven element on it such as an arcuate slot receiving the pin or a second shoulder so that there is a lost motion between these elements that is eliminated in the direction of a setting movement before the setting movement begins. This lost motion is then recovered and utilized after the timer rundown in the opposite direction for a snap opening of the switch as the opening of the switch begins.

Preferably, there are two switches that are controlled and the knob has stepped cams on it on opposite sides of a notch which fully opens both switches in the "OFF" position. One of the cams closes only the motor energizing switch and the other cam closes both the motor and timer energizing switches. For instance, when the knob is turned in one relative direction, the lost motion between the drive and driven elements is taken up in that direction and stored in the system. The elements go solid in that relative direction and remain that way with both the motor and timer energizing switches closed by said timer cam. The timer switch energizes the timer and its gear moves in the opposite direction, maintains the solid relationship, and returns the timer cam to a critical point where the resiliency in the switches drives the knob with a lost motion snap action to its OFF position. Manual movement of the knob in the opposite direction does not necessarily involve lost motion but it closes the motor switch alone for a manually terminated timed operation. The switches tend to center the knob in a fixed OFF position against a feeling of looseness until manually turned in either selected direction as just described.

Whether a timer embodies a lost motion in the rundown time interval or eliminates it from the interval as just mentioned, a pushbutton or lever, actuated independently of the knob can either actuate the motor energizing switch directly or cam operate the knob with a limited motion in said opposite direction to energize the motor as long as it is manually held to provide a momentary manually held energization of the motor. This sometimes is referred to operationally as "jogging." On the other hand, only the knob need be used to operate the switches for all functions. The relationship is one wherein the knob is manually turned in one direction to actuate both the switches without lost motion and in the opposite direction to actuate only the motor switch. The timer drive also turns the knob in said opposite direction to deactivate the switches with said snap lost motion action.

The operational relationship thus provided objectively fits in with the natural habits of the user in that the knob is turned to cooperate with the observed timer scale and indicates the exact period of the setting, as well as indicating accurately the period of time remaining during operation. Turning the knob in the opposite direction for manual actuation provides the manual timing which is expected by the user upon the first use. And, when in "OFF" position, the operation of the "jog" button is immediately understood if the user does not desire to use the knob for that purpose.

A speed selection pushbutton switch, such as described in the Swanke application, reference to which is hereby made, can be connected in series with the liquidizer motor switch while the serially connected timer motor and timer switch are connected across the power connections. Thereby the knob can be "over set" and start to run down before the liquidizer motor is started by the pushbutton speed switch. Then the liquidizer motor can be started the moment the desired time increment indicator is reached by the knob. Also, if the liquidizer motor is shut off before the timer rundown is completed, such will be continued until the OFF position of the timer knob is attained.

It will be noted, however, that the timer motor switch may also be connected in series with the main switch, if desired, because the knob being left in any position can be reset from that position as easily as from OFF position at the next operation.

Another object of the invention is to jog the liquidizer motor at the last speed setting made for the liquidizer unless another speed setting is made selectively for a different speed.

In event an "OFF" operation is not provided in a manual pushbutton switch the timer OFF position can be utilized.

Preferably the circuit is arranged so that the one operatively OFF switch is connected proximate to one power line and the other operatively OFF switch is proximate to the other power line so that a complete cutoff of power from both lines is accomplished for the appliance when the liquidizer is idle.

These being among the objects of the invention, other and further objects and advantages will become apparent from the description and the drawings which follow.


FIG. 1 is a fragmentary perspective view of a liuqidizer and time-speed control including a multiple pushbutton switch embodying the invention;

FIG. 2 is a partial cross-sectional view through the control panel shown in FIG. 1 illustrating in side plan view an embodiment of the invention as taken on line 2-2 of FIG. 1;

FIG. 3 is a cutaway view of the embodiment shown in FIG. 2 illustrating the cooperating parts in the jogging operation;

FIG. 4 is a diametral sectional view of the switch portion of the timer shown in FIG. 2;

FIG. 4A is an enlarged sectional view of the slip clutch and lost motion drive mechanism shown in FIG. 4;

FIG. 5 is an enlarged sectional view of the cooperating actuator and switch elements;

FIGS. 6, 7, 8 and 9 are sectional plan views of the elements in the switch portion of the housing in different stages of operating as taken on line 6-6 of FIG. 4;

FIG. 9A is an enlarged sectional view of the lost motion elements interconnecting the knob and the return drive elements shown in FIGS. 6 and 7;

FIGS. 10 and 11 are plan views in spaced plans illustrating another embodiment of the invention; and

FIG. 12 is a sectional view of a further embodiment of the actuator of the invention.


Referring now to the drawings in further details in a liquidizer embodying the invention is shown in FIG. 1 comprising a base 10 that houses a universal motor 12 diagrammatically shown in FIGS. 6 and 7. A switch control panel 14 supports a pushbutton switch 16 on the base and a timer assembly 20 for controlling the speed of the motor, and the time period that the motor is to be energized. A liquidizing jar 22 with rotatable cutters in it is received in a collar 18 on top of the base in its operative position for actuation by the motor 12 when energized.

The timer assembly 20 includes a scale 28 graduated in seconds up to 70 seconds and a knob 24 having a pointer handle 26 which when rotated clockwise from a central or "OFF" position activates the timer to provide a selected time cycle for motor operation and when rotated counterclockwise as viewed in FIG. 1 the timer serves as an "ON" and "OFF" switch that energizes the motor continuously until returned to "OFF" position. A jog button 30 is provided to directly control the timer switch to energize the motor with short bursts of manually controlled power when the knob is in its "OFF" position and it is to be noted that these short bursts of power can also be provided in the embodiment by slight counterclockwise movement and release of the knob 24 to close momentarily the same switch that is closed by the jog button 30. Accordingly, either the knob 24 or the button 30 can be manually actuated directly or, if desired, the button can be arranged to actuate the knob for the same purpose. Separate control, however, is preferred.

In the embodiments disclosed the switch construction as shown in FIGS. 2 and 4 comprises a housing 32 made up of two sections. One section is a sealed timer motor and gear reduction assembly 34 having electrical power leads 36 for energizing a synchronous motor 13 (FIG. 6) and a low speed torque output spur gear 38. The other section is a switch housing 40 receiving the spur gear through a back opening 42 therein to engage a large gear 44 in drive relationship that is journaled on a shaft 46 again.

A spring washer 48, rotatably secured to the shaft, frictionally engages the inner face 50 of the gear 44 which is held in place by a shoulder 52 that is provided by one side of a collar 54 that is locked to the shaft. A radially and axially extending key 56 extends from the other side of the collar to interengage a control disc 58 made of a dielectric material and journaled on the shaft. The knob 24 operates the disc as a unitary part thereof.

The interengagement mentioned provides a rotatively exercised lost motion between the control knob-disc unit and the collar-key unit in that the disc 58 and key 56 are disposed in the same plane rotationally with the key received in a disc opening 60 that is larger than the key. The opening 60 has radial walls 62T and 62M circumferentially spaced a distance greater than the like dimension of the key to provide a substantial lost motion relationship between alternate engagements of the walls with the key. Thus, when the wall 62T of the disc engages the key 56, the collar 54 is moved clockwise, slipping the clutch 48 on the inner face 50 of the gear 44 and providing a new relationship between the gear 44 and the key 56 whereby timer "rundown" by the synchronous motor with the shaft rotated counterclockwise as indicated by the arrow 46A will keep the key 56 in contact with the wall 62T and move the disc-knob unit in the the counterclockwise direction, and do so immediately, for the exact period of time selected by the knob without any lost motion between them.

Referring to FIGS. 6 and 7 this interaction and relationship mentioned are implemented in connection with the control switches in which three switch blades 64, 66 and 68 are mounted in a housing opening 63, in parallel relationship in the housing with their free ends lying in the plane of the disc 58. The free ends of the blades carry make and break contacts 72 cooperating with each other for the closure of adjacent contacts to provide two single pole, single throw switches 74T and 74M with the intermediate blade and contacts common to both switches for a double switching action.

The lowermost blade 68 is formed intermediate its ends to provide a V-shaped follower 70 engaging the rim of the disc 58 to sequentially close switch 74M first and then switch 74T and open in the reverse order. This is accomplished with three cam levels at the rim of the disc cooperating with the follower 70. One cam level is in the nature of a relief 0 which receives the follower in a radial direction far enough to open both switches 74M and 74T, as shown in FIG. 8, which is the "OFF" relationship indicated. To the left of relief 0, as viewed in FIG. 6, another cam T is provided which is high enough above the relief 0 to close both switches while to the right of the relief 0 as viewed in FIG. 7 a cam M of intermediate depth is provided to close only switch 74M or open switch 74T if it was closed.

It will be noted in FIG. 8 that the width of the V-follower 70 is substantially the same as the peripheral width of the recess 0 and, although the recess can be somewhat square in shape for ease of manufacture, it is shown as the same shape as the V-follower so that the inclined elements involved mate and slidably engage when the disc 58 is turned in either direction from the "OFF" position shown in FIG. 8. This provides a firm feel of this knob to the user. Also the V-follower 70 when it is returned from either of the positions shown in FIGS. 6 and 7 will provide a snap action movement back to its "OFF" position once the apex of the V-follower is no longer supported on either cam surface T or M. Furthermore, it will be appreciated that the disc can be moved momentarily counterclockwise to close the lower switch while the cam follower is still on the incline towards cam M and then released to accomplish a jogging energization of the liquidizer motor. This the user can do and may prefer to do, if so desired, for jogging.

However, in simplifying the understanding or operational control techniques for the user, a separate pushbutton 30 is provided that is slidably mounted in a boss 80 secured on the side of the timer housing (FIGS. 3 and 5) and a bent wire activator 82 for engaging the lower blade is provided. The activator is pivotally fulcrumed in the housing on an intermediate portion 84 with a lever arm 86 disposed at right angles thereto at one end and engaged by the pushbutton 30. The other end of the wire form serves as a crank arm portion 88 thereof engaging the switch blade 68. The free end of the lever portion 86 is received in a slot 87 cut longitudinally in the pushbutton at its inner end where it is engaged by the end wall portion 89 of the slot when the button is depressed. Finger pressure applied to the button accordingly operates to displace the lever portion 86, rotate the fulcrum portion 84 and drive the crank portion 88 to close the contacts of only switch 74M of the liquidizer while the follower 70 is in "OFF" position.

In the embodiment illustrated, the housing is provided with a hole 90 through the sidewall large enough to receive the crank portion 88 therethrough to lodge the fulcrum portion 84 in pivotally supported relation in a cradle groove 91 (FIG. 5). Thereupon the boss 80 (FIG. 6) with a split forming a guide way 92 in the plane of the movement of the lever portion 86 is secured in place on the housing to hold the actuator 82 in operative position. The pushbutton 30 is then installed by inserting it endwise into its operative position.

Stepped stops 65, 67 and 69 are internally cast in the housing as shown in FIGS. 6 to 9 for supporting the free ends of the spring blades 64, 66 and 68, respectively, in spaced relation to assure the switches are open when not actuated. For this purpose it will be noted that the switch blades progressively extend different lengths. As seen in FIG. 9 blade 64 extends the farthest to engage stop 65, blade 66 engages stop 67 and blade 68 engages stop 69. They are resiliently tensioned to do this when neither the disc 58 nor the actuator 82 engages them. The actuator 82 is limited in its movement to close only switch 74M, as already mentioned, in which case the blade 68 and its contact engage only the blade 66 and the lower one of its contacts.

The anchored ends of the switch blades may be straight when anchored in the housing but to assure and maintain them in exact position, they preferably are bent at 64E, 66E and 68E as shown in FIGS. 6 and 7 with production accuracy to locate the free ends with respect to the stops 65, 67, and 69 as described. Then spacer type wedges 64W, 66W and 68W angled to nest in the elbow bends of the blades are provided to cooperate with a correspondingly angled seat element 61 cast in the housing 40 as part of one wall of the opening 63 in which the blade support assembly is mounted. The elbow 68E of blade 68 snugly rests in the angle 61E of the element 61 and is wedged there by the L-shaped anchor member 68W. Likewise with the remaining switch blades. The elbow 66E rests in the angle 66A of the anchor member 68W where it is held by the anchor member 66W which in turn receives the elbow 64E of blade 64 which is wedged in place by the wedge 64W which closes the opening 63.

The circuitry implementing the action of the switches is illustrated as two modifications in FIGS. 6 and 7 and reference is made to the Swanke application for the speed control circuit controlled by the pushbutton switch.

In FIG. 6 the timer motor 34 is connected between the power line L 1 and switch blade 64 by connections 36 with respect to switch 74T. The motor 12 and the pushbutton switch 16 are serially connected between the blade 68 with respect to switch 74M and the power line L1 and the blade 66 is connected to the other power line L2 with respect to both switches 74T and 74M whereby the timer motor 34 and the serially connected motor 12 and switch 16 are connected in parallel when both switches 74T and 74M are closed. If the stop button 16S on the pushbutton switch 16 is pressed during a liquifying cycle the timer motor will continue to be energized and will run down and turn off the timer switch also ready for a full reset the next time of use.

In FIG. 7 the power line L2 is connected to blade 68 while the serial connection of motor 12 and the pushbutton switch 16 is connected serially with both of the motors 34 and 12, whereby they are connected in parallel when both switches 74T and 74M are closed. With this arrangement the liquidizer appliance is protected by switches being located at both power line connections and the timing period can be interrupted and resumed without loss of time accuracy.

In FIGS. 10 and 11 the jog action is accomplished with a lever 86A journaled on the panel 14 by a pin 84A that carries a rocker arm 88R located in close proximity to the blade 66A. When the lever 86A is tilted in either direction the rocker arm 88R closes the switch 74A. In this embodiment the switch 74A serves either as timer switch alone or as both the timer switch 74T and power switch 74M combined when the disc 58A is in its "OFF" position. In the latter the connections 12C and 36 (FIG. 7) are a common connection.

In FIG. 12, if the pushbutton 86B is located directly above the knob 28 it may be slidably mounted in an opening 92 in the panel 14 and directly actuate the switches 66A and 68A in FIG. 11 by its rounded end 93 as held in working position by the retainer flange 94 thereon. Its action is represented in broken lines which includes a person's finger 95.

Having thus disclosed the several embodiments and their operation with the description of each Figure it will be appreciated how the various objects and advantages are attained and how changes in dimensions and arrangements can be made therein without departing from the scope of the inventive concept set forth.