WO1997015264A1

WO1997015264A1 - Control for vibratory motors and power supply therefor

Info

Publication number: WO1997015264A1
Application number: PCT/US1996/016851
Authority: WO
Inventors: Mark J. Raffel; Greg J. Elliott; David Vang
Original assignee: Raffel Product Development, Inc.
Priority date: 1995-10-24
Filing date: 1996-10-22
Publication date: 1997-05-01
Also published as: CA2233665A1

Abstract

A massaging system for use in an article of furniture includes a plurality of vibrators (1L, 1R to 5L, 5R), constructed and arranged to be positioned in spaced apart relation on the article of furniture (10), a power source (22) and a plurality of switching devices (24) selectively connecting the vibrators to the power source (22) in a sequence dependent upon the receipt of predetermined input signals. A processor (34) is coupled to the switching matrix (27) and includes a memory in which a plurality of signal sequences are stored. A selector (27) is coupled to the processor (34) and has a plurality of individual actuators (SW1-SW12), each operative for providing a predetermined input singal to the processor. The processor (34) is operative to access a different one of the signal sequences and for outputting the signal sequences to the switching devices (24) upon the selection of each of the plurality of actuators (27) so that the vibrators will be actuated in a different predetermined sequence upon the selection of different ones of the actuators (27). A full wave rectifier (225) having input terminals (223, 224) connected to a power supply (216) and a pair of output terminals (244) for providing full wave rectified current.

Description

CONTROL FOR VIBRATORY MOTORS AND POWER SUPPLY THEREFORE

BACKGROUND OF THE INVENTION This invention relates to a massaging apparatus, and more particularly, to a control for a massaging apparatus incorporated into an article of furniture.

Body massage systems generally comprise an article of furniture, such as a mattress, lounge or chair having a plurality of vibrator motors which are energized in a variety of predetermined sequences so as to provide the desired massaging effect. One such prior art massaging apparatus is disclosed in U.S. Patent No. 5,437,608. Such prior art systems where not wholly satisfactory, however, because they incorporated complex circuitry and had limited flexibility.

Energy for the vibrating motors of such prior art systems was generally provided by transformers and rectifiers which coupled the motors for receiving alternate half cycles of the power supply system. The energy level was adjusted by controlling the duration of each motor energizing pulse. Because of the heat dissipation requirements in such systems, relatively large transformers are required. -2- SUMMARY OF THE INVENTION

It is an object of the invention to provide a new and improved vibrator system for body massage apparatus.

Another object of the invention is to provide a vibrator system for a body massage apparatus which provides increased flexibility for energizing a plurality of vibrator motors in a variety of predetermined sequences.

A further object of the invention is to provide a simple and inexpensive control for a plurality of vibrating motors used in massaging furniture.

Yet another object of the invention to provide a new and improved energy supply for the vibrator system of a body massage apparatus.

A still further object of the invention is to provide an energy supply for the vibrator motors of a body massage apparatus which permits the use of a relatively smaller transformer.

Yet another object of the invention is to provide a more efficient power supply for the vibrator motors used in massaging apparatus.

According to another aspect, the invention comprises a vibration producing system for use in an article of furniture and including at least first and second vibrating means coupled to the article of furniture for producing vibrations upon being energized, a power supply for the vibrating means including a source of alternating current and full wave rectifying means having input terminals connected to the power supply and a pair of output terminals for providing rectified current from the output terminals. The invention also includes a first switch means coupled to the first vibrating means and the rectifying means and having a first mode for connecting the first vibrating means to the output terminals so that the first vibrating means receives full wave rectified current therefrom, a second mode for connecting the first vibrating means to the rectifying means so that the first vibrating means receives successive half waves of the alternating current having a first polarity and a third mode for open circuiting the first vibrating means. In addition, the invention also includes second switch means coupled to the second vibrating means and the rectifying means having a first mode for connecting the second vibrating means to the output terminals so that the second vibrating means receives full wave current therefrom, a second mode for connecting the second vibrating means to the rectifying means so that the second vibrating means receives successive half waves of the alternating current having a second polarity, and a third mode for open circuiting the second vibrating means.

The invention also comprises a method of controlling the level of energy supplied to a pair of vibrators coupled to an article of furniture for imparting vibrations in spaced apart locations to a user mounted thereon, comprising the steps of selectively supplying one of the vibrators with either full wave rectified current from an alternating current source for generating maximum vibration intensity, a half wave of the alternating current having a first polarity for generating low vibration intensity or open circuiting the one vibrator, selectively supplying the other vibrator with either full wave rectified current from the alternating current source to provide a high level of vibration intensity, a half wave of the alternating current source and having a different polarity for providing a low level of vibrating intensity, or open circuiting the second vibrator whereby the full wave rectified current is utilized when both of said vibrators are either set for high vibration intensity or low vibration intensity.

These and other objects and advantages of the present invention will become more apparent from the detailed description thereof taken with the accompanying drawings.

In general terms, the invention comprises a massaging system for use in an article of furniture, and including a plurality of vibrators constructed and arranged to be positioned in spaced apart relation on the article of furniture, a power source, switching means for selectively connecting the vibrators to the power source in a sequence dependent upon the receipt of predetermined input signals, a processor coupled to the switching means for providing output signals, the processor including a memory, a plurality of signal sequences stored in the memory, a selector coupled to the processor and having a plurality of individual actuators, each actuator being operative for providing a predetermined input signal to the processor, the processor being operative to access a different one of the signal sequences and for outputting the signal sequences to the switching means upon the selection of each of the plurality of actuators so that the vibrators will be actuated in a different predetermined sequence upon the selection of different ones of the actuators.

According to another aspect, the invention comprises a method of controlling a plurality of signals on each output for varying the integral of the electrical energy transferred from the power source to the vibrators upon the receipt of the input signals.

BRIEF DESCRIPTION OF THE DRAWINGS Figure 1 schematically illustrates a massaging apparatus incorporating the present invention;

Figure 2 schematically illustrates a control for use with the massaging apparatus illustrated in Figure i; Figure 3 is a flow diagram illustrating the operation of the control shown at Figure 2; and

Figure 4 illustrates the vibrator actuating signals for the massaging apparatus shown in Figure 2.

Figure 5 shows an alternate embodiment of the invention.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT Figure 1 schematically illustrates an article of furniture 10 which may be a chair, a lounge, a mattress or the like. The article of furniture is symbolized by a pad 12, such as foam, and the plurality of vibrators IL, IR, 2L, 2R, 3L, 3R, 4L, 4R, 5L and 5R. The designation L indicates that the vibrator is on the left side as viewed in FIGURE 1, and the designation R indicates that the vibrator is on the right side. The vibrators 1L-5R are preferable mounted on or in cavities formed in the foam pad, but may alternately be mounted on the furniture frame (not shown) or springs (not shown) which support the pad 12. The number of vibrators used will depend upon the areas of the body to be massaged and the desired massaging pattern. Also, while ten vibrators are shown, any suitable number may be employed without deviating from the present invention. In addition, while the vibrators are shown to be arranged in pairs, they may be mounted singly. The vibrators IL and IR are located at the upper back region of pad 12, 2L and 2R at the lower back region, 3L and 3R at the seat region, 4L and 4R at the leg region and 5L and 5R at the feet region.

The vibrators IL, IR, 2L, 2R are connected by conductors 14, 15, 16 and 17, respectively, and vibrator pairs, 3L-3R, 4L-4R and 5L-5R are connected by conductors 18, 19 and 20, respectively, to switches 24 which in turn are operative to connect the individual vibrators 1L-5R to the power source 22 in response to signals from the control 26 which, in turn, is actuated by switching matrix 27 having individual selector switches SW1-SW12. In addition, a heater coil 28 may also be mounted in the pad 12 and is also energized in response to a signal from control 26. Vibrations from the vibrators 1L-5R are transmitted through the pad 12 and a covering material to the user.

Referring now specifically to Figure 2, the control 26 is shown to include a processor 32 having a programmable read only memory (PROM) 34. The processor 32 receives input signals from the switching matrix 27 and provides output signals in accordance with the program stored in PROM 34 for actuating vibrators IR, IL . . . .5R and 5L in a predetermined sequence, depending upon which of the switches of matrix 27 are actuated.

The vibrators 1L-5R may comprise any well known type of electrical device which produces vibrations upon being energized. In the preferred embodiment, they comprise electric motors having an eccentrically weighted output shaft.

Any suitable relationship between the switches SW1-SW12 and the vibrators 1L-5R can be established. In the illustrated embodiment, switch SWl may be coupled to turn on vibrators IL and IR, SW2 to turn on vibrators 2L and 2R, SW3 to turn on vibrators 3L and 3R and SW4 to turn on vibrators 4L, 4R, 5L and 5R. Switch SW5 may be coupled to turn the power on and off, SW6 to actuate all of the vibrators at the same time, SW7 to turn the heating coil 28 on and off, SW8 to control the vibrator sequence from IR and IL to 5R and 5L or from 5R and 5L to IL and IR. Switch SW9 may be coupled to increase the wave speed, i.e., the speed that the sequence proceeds between successive vibrators; SW10 may be set to decrease the wave speed; SW11 may be set to increase wave intensity and SW12 may be set to decrease wave intensity.

Switches 24 may comprise any suitable switching devices. In the illustrated embodiment, the switching device is comprised SCRs ElR, E1L, E2R, E2L, . . . E5R and E5L. The gates of SCRs ElR, E2R, E3, E1L, and E2L are connected respectively to the output terminals j, k, 1, p, and q of processor 32 and the gates of SCRs E4 and E5 are connected to terminal m. The anode-cathode circuits of SCRs ElR, E1L, E2R and E2L are connected respectively to vibrators IR, IL, 2R and 2L, and the anode-cathode circuits of SCRs E3, E4 and E5 are respectively connected to vibrators 3R and 3L, 4R and 4L and 5R and 5L. Terminal m of processor 26 is connected to the gate of triac E6 and terminal o is connected to LED_j. Accordingly, when a signal appears on output terminal j of processor 26, vibrator IR is actuated; a signal on output terminal k actuates vibrator 2R, a signal on output terminal 1 actuates vibrators 3R and 3L, a signal on output terminal m actuates vibrators 4R, 4L 5R and 5L, a signal on output terminal n actuates heater 25, a signal on output terminal p actuates vibrator IL, a signal on output terminal q actuates vibrator 2L and a signal on output terminal o actuates LEDj. LED₂-LED₆ are also provided to indicate the presence or absence of output signals on terminals j and p, k and q, 1, m and n, which in turn indicates the actuation of the switching devices connected thereto.

When an output signal appears on one of the terminals j-m, p or q, the SCR whose gate is connected thereto becomes conductive to actuate its associated vibrator. The actuated vibrators remain energized so long as the gate signals continue to their respective SCRs. The program stored in the PROM 34 instructs the processor regarding the sequence of signals to each of the SCR gates in accordance with those of switches SW1- SW12 that have been actuated. If all the vibrators are to be actuated simultaneously and continuously, the appropriate gate signals are also continuous. Figure 3 shows the sequence of signals, in the form of square wave pulses provided to the SCR gates under one operating mode. For example, if the vibrators 1R-5L are to be actuated in a given sequence, a series of square wave pulses are provided to the gates in the appropriate sequence. Assume for example that the sequence of vibrator actuation is to be 1R-1L; 2R-2L; 3R-3L; and 4R, 4L, 5R and 5L. At time t_x, a series of square wave pulses appear on each of terminals a and g as shown in FIGURE 3. These pulses increase in width from zero to a maximum and then begin decreasing back to zero. At time t₂, prior to the termination of the pulses on terminals j and p are continuing, a second series of square wave pulses appear on terminals k and q. At time t₃, a third series of pulses appear on terminal 1 and at time t₄ a fourth series of pulses appear on terminal m. At time t₅ the signals reappear on terminals j and p and sequentially on the remaining terminals and this continues until the operator terminates the messaging operation or it is terminated or changed by the program as will be discussed more fully below. These signals result in a wave action from the head to the feet. If the sequence is reversed, the wave action is from the feet to the head. In a similar manner, wave actions can be produced horizontally between vibrators IR, IL and/or 2R and 2L or pairs of vibrators can be energized simultaneously. /15264

-11-

The speed of the travelling wave between vibrators or a group of vibrators is determined by the rate at which sequential vibrators are energized. Thus, by shortening the time between t_t and t₂, t₂ and t₃, and t₃ and t₄ and so forth, the speed of the wave can be increased and conversely by lengthening these times, the speed of the wave can be decreased. The width of each of the pulses shown in Figure 3 determines the point in each rectified half wave from the power source that the SCR is energized. Because the signals increase in width to a maximum and then decrease, the integral of the rectified full wave power signal during each half cycle similarly increases and decreases so that there is a similar increase and decrease in the vibrating intensity of the applicable vibrator. By increasing the width of the signal, the vibrator receives a greater portion of the energizing current in each half wave and by decreasing the width of each pulse, a smaller portion of the current will be provided during each half cycle. Accordingly, the intensity of the energy provided to each of the vibrators can be adjusted by adjusting the widths of the pulses shown in Figure 3.

It will be appreciated that the pulses shown in Figure 4 are for purposes of illustration only and are not intended to represent either the number of pulses in each cycle or the relative widths. Figure 4 schematically illustrates the program stored on PROM 34 for controlling the sequence of vibrator operation. After the program is initiated at

100 by actuating switch SW5, the program determines at

101 whether or not switches SWl and/or SW2 have been closed indicating that the back and/or lumbar outputs are desired. If the back and lumbar output is requested, vibrator IL, IR, 2L and 2R are actuated. On the other hand, if full body output is requested, all of the vibrators are actuated. In either case, the program proceeds along parallel paths. Initially, the program then proceeds to determine at 102 if switch SW7 has been actuated indicating that the heater is requested. If heat is requested, at 103 a gate signal is provided to triac E6 which actuates the heater. In addition, the power supply initially provided to heater 25 is relatively large to insure a rapid rise in temperature. After a short time delay, the power supplied to the heater is reduced so that the transformer T, does not overheat. This relatively short oversupply of energy to he heater will be sufficient to heat up the padding material surrounding the heater and which will retain the heat when the power supply is reduced. At 104, the program determines the massage type. If switch SW6 has been closed, the pulse effect is requested, that is, all of the vibrators are actuated simultaneously with square pulses as shown, for example in Figure 4 (j, p). If switch SW8 has been closed to request a wave effect, the vibrators are actuated in an overlapping sequence by the series of square pulses as discussed with respect to Figure 3. The program also checks which of the individual vibrator switches may be in the off position at 105, 106 or 107 depending upon the request in the event that less than all of the vibrators are to be operated during the pulse or wave effect.

After determining the number of vibrators that are activated, the program determines at 108 whether more than a selected number are indicated. If so, the intensity level to all vibrators is reduced at 110 so that the power being drawn does not exceed the power rating of the transformer T₁ that forms a part of the power supply. The number will depend upon the transformer rating and the maximum current supplied to the vibrators. In the illustrated embodiment, this number is six vibrators. If more than six vibrators are requested, the power level to each is reduced. This step can alternatively be performed at 132 as illustrated in Figure 4.

The processor includes a timer which turns off the massager after a predetermined time, such as twenty minutes after actuation. The program determines at 111 whether the timer is at one minute before a timeout. If so, LEDj is flashed. At 112, the system determines if it has timed out at 114 and if so, at 116 it saves the last setting and turns off the vibrators and/or the heater. However, the operator can override the system which will then revert to 118.

At 118, 119 and 120, the program continually scans the switches SW1-SW12 to determine if there has been a change in the array of switches that have been pushed. If additional buttons have been pushed, the system makes a copy at 121 and then at 122 determines whether there is a different array of switches that are activated. If there has been a change in the array of actuated switches the system proceeds to 116 to determine which new functions are indicated. If the same switches are pressed, the system determines whether the time delay is zero at 124 and if so, the time delay is reset at 126. The system then determines whether the power on and power off, fast speed or slow speed switches have been activated at 128 and if so, proceeds to determine what new functions are indicated at 130 and 132. The system then determines whether the ramp up or ramp down switches have been pushed.

To ramp up or ramp down, that is, to control the intensity of the vibrator oscillation, the gate signals to the SCR are phase controlled so that the vibrators are actuated at a desired point in the rectified half sign wave. If ramp up is actuated, the widths of the signals in Figure 3 are widened and if ramp down is indicated, the width of the signals are decreased.

Figure 5 shows an alternate embodiment of the invention as applied to an article of furniture 210 which may be a chair, a lounge, a mattress or the like. The article of furniture is symbolized by a pad 212, formed of any suitable material and at least a pair of vibratory motors 213 and 214. It will be appreciated that the pad 212 may be supported by a pid and springs (not shown). The vibratory motors 213 and 214 may be coupled to the article of furniture 210 in any suitable manner. For example, motors 213 and 214 may be mounted on the frame, the springs in the padding 212, or they may be mounted on tubular members which are inserted between portions of the article of furniture, such as between a chair and a cushion, or a mattress and a box spring. In the illustrated embodiment, the vibratory motors are shown to be mounted in the pad 212 for purposes of illustration. The position of the vibratory motors 213 and 214 relative to the article of furniture 210 depends upon the areas of the body that are to be vibrated. In the illustrated example, the vibratory action would be in the upper and lower back. The vibrators 213 and 214 may comprise any well known type of electrical device which produces vibrations upon being energized. In the preferred embodiment, the vibrators 213 and 214 comprise electric motors having an eccentrically weighted output shaft.

The power supply circuit 215 for the vibrator motors 213 and 214, includes a transformer 216 having a primary winding 218 connected to a power source 220, such as, a 60 cycle, 120 volt system. The secondary winding 222 of transformer 216 is connected to the input terminals 223 and 224 of a full wave rectifier 225 consisting of diodes DH, D12, D13 and D14. The rectifier 225 is connected to motor 213 through switch SW21 which has a first mode for connecting the motor 213 for receiving full wave rectified current from the rectifier 225, a second mode for connecting the motoring 213 for receiving successive half waves of the rectified current having a first polarity from the transformer secondary winding 222 and a third mode for open circuiting the motor 213. Similarly, the rectifier 225 is connected to the motor 214 through the switch SW22 which has a first mode for connecting the motor 213 for receiving full wave rectified current from the rectifier 225, a second mode for receiving half wave rectified current having a second polarity from the transformer secondary winding 222 and a third mode for open circuiting the motor 214. While any mechanical or electronic switch capable of performing these functions may be employed, switch SW21 is symbolized by a mechanical switch having contacts 226, 228, 230 and 232 and slide member 233 and switch SW22 is symbolized by a mechanical switch having contacts 234, 236, 238 and 240 and slide member 241. The slide members 233 and 241 are movable to selectively connect pairs of adjacent contacts.

Switch contacts 226 and 234 are each connected by conductor 243 to the rectifier output terminal 244, contacts 228 and 236 are connected by conductors 246 and 248 to vibratory motors 213 and 214, respectively. Contacts 230 and 238 are connected by conductors 250 and 252 to the input terminals 223 and 224, respectively, of rectifier 225. Contact pair 226 and 228 of switch SW21 are labeled HI, contact pair 228 and 230 are labeled LO, and contact pair 230 and 232 are labeled OFF. The corresponding contacts of switch SW22 are similarly labeled.

When the contact 241 is positioned to connect terminals 230 and 232 and the contact member 242 is positioned to connect terminals 238 and 240, each of the motors 213 and 214 is open circuited. Movement of the contact member 241 to contacts 226 and 228, or the HI position, connects motor 213 to output terminal 244 of rectifier 225 through conductors 243 and 246. As a result, the motor 213 receives the full wave rectified or maximum current. Similarly, movement of contact member 242 to contacts 234 and 236 connects motor 214 to terminal 244 through conductors 243 and 248 so that motor 214 also receives the full wave rectified current.

Movement of contact member 241 to contacts 228 and 230 and contact member 242 to contacts 236 or 238, or the LO positions, connects motor 213 to rectifier terminal 224 through conducts 246 and 250 and motor 240 to rectifier terminal 226 through conductors 248 and 252. During each positive half cycle of the alternating output current from transformer secondary winding 222, that is, when terminal 224 is positive, and terminal 226 is negative, motor 213 is energized while motor 214 is grounded through diodes D24. During each negative half cycle, that is when terminal 224 is negative and terminal 226 is positive, motor 214 is energized and motor 213 grounded through diode D22. It can be seen, therefore, that when the switches SW21 and SW22 are each in their HI positions, motors 213 and 214 are energized by full wave rectified current. On the other hand, when each of the switches SW21 and SW22 are in the LO positions, the motors 213 and 214 are energized by alternate half cycles of the rectified current. As a result, the current flowing through the motors 213 and 214 is balanced and, in each case, the full wave is utilized. As a result, heating of the transformer 216 is minimized and a relatively smaller transformer can be employed.

LEDs D15 and D16 may be connected to conductors 246 and 248, respectively, for indicating when the motors 213 and/or 214 are energized.

While only a few embodiments of the invention is illustrated and described, it is not intended to be limited thereby, but only by the scope of the appended claims.

Claims

I CLAIM :

1. A massaging system for use in an article of furniture, said system including a plurality of vibrators constructed and arranged to be positioned in spaced apart relation on the article of furniture, a power source, switching means for selectively connecting the vibrators to said power source in a sequence dependent upon the receipt of predetermined input signals, a processor coupled to said switching means for providing output signals, said processor including a memory, a plurality of signal sequences stored in said memory, a selector coupled to said processor and having a plurality of individual actuators, each actuator being operative for providing a predetermined input signal to the processor, said processor being operative to prepare a different one of said signal sequences and for outputting said signal sequences to the switching means upon the selection of certain of said plurality of actuators so that the vibrators are actuated in a different predetermined sequence upon the selection of different ones of said actuators.

2. The massaging system set forth in claim 1 wherein said switching means comprises a plurality of electronics switching means, each of said electronic switching being operative to connect a different one of the vibrators to said power source upon the receipt of a control signal, said processor being operative to provide control signals on multiple outlets, each of said outlets being connected to a different one of said electronic switching means, said processor being programmed to provide an individual control signal on said outlets in a predetermined sequence upon the selection of each of said plurality of actuators.

3. The massaging system set forth in claim 2 wherein said processor is programmed to provide the signal sequences to said multiple outlets in a succeeding time delayed relation between commencement of each signal sequence on one outlet and the preceding signal sequence on another outlet, said processor being programmed for varying the time delay between the initiation of the signal sequences on said multiple outlets upon the receipt of a predetermined signal from the selector.

4. The massaging system set forth in claim 2, wherein said processor is programmed to vary the duration the signals on each output for varying the integral of the electrical energy transferred from the power source to said vibrators upon the receipt of a predetermined signal from one of said actuators.

5. The massaging system set forth in claim 4 wherein said processor is programmed to provide the signal sequences to said multiple outlets in a succeeding time delayed relation between commencement of each signal sequence on one outlet and the preceding signal sequence on another outlet, said processor being programmed for varying the time delay between the initiation of the signal sequences on said multiple outlets upon the receipt of a predetermined signal from the selector.

6. The massaging system set forth in claim 5 wherein said processor includes means for determining the number of vibrators actuated and for reducing the duration of the signals if more than a predetermined number of vibrators are connected to the power source.

7. The massaging system set forth in claim 1, wherein said processor is programmed to vary the duration the signals on each output for varying the integral of the electrical energy transferred from the power source to said vibrators upon the receipt of a predetermined signal from one of said actuators.

8. The massaging system set forth in claim 1 and including heater means for heating said article of furniture, said switching means also being operative to connect said heater means to said power source upon the receipt of a predetermined heat signal from said processor, said selector including an actuator for providing said processor with a heater on signal, said processor being operative to provide said heat signal upon the receipt of said heater-on signal.

9. A method of controlling of plurality of vibrators constructed and arranged to be positioned in spaced apart relation on an article of furniture for producing a massaging effect, the steps of providing selected input signals to a processor from a group of possible input signals, accessing a different one of a group of signal sequences stored in the processor memory depending upon the input signal selected, outputting the signal sequence selected from the processor memory to switching means, connecting the vibrators to a power source in a sequence depended upon the signal sequence received from the processor memory.

10. The method set forth in claim 9 and including the step of providing one of a plurality of signal sequences stored in the processor memory to multiple outlets upon the receipt of each input signal of the group of input signals, and actuating separate switching means coupled to each of the outlets for selectively coupling said vibrators to the power source in accordance with the sequence of signals provided at said multiple outlets.

11. The method set forth in claim 10 including the step of varying the duration of the signals on each output for varying the integral of the electrical energy transferred from the power source to the vibrators upon the receipt of the input signals.

12. The method set forth in claim 10 and including the step of delaying the activation of selective switching means and varying the time delay between the actuation of the separate switching means.

13. The method set forth in claim 11 including the step of varying the duration of the signals on each output for varying the integral of the electrical energy transferred from the power source to the vibrators upon the receipt of the input signals.

14. A vibration producing system for use in vibratory furniture and including at least first and second vibrating means for producing vibrations upon being energized, rectifying means connected to an alternating current power supply for rectifying the alternating current from the power supply, first switch means having a first mode for connecting said first vibrating means to said rectifying means so that said first vibrating means receives full wave rectified current therefrom, a second mode for connecting said first vibrating means to said rectifying means so that said first vibrating means receives alternate half waves of the alternating current having a first polarity and a third mode for open circuiting said first vibrating means, second means having a first mode for connecting said second vibrating means to said rectifying means so that said first vibrating means receives full wave rectified current therefrom, a second mode for connecting said second vibrating means to said rectifying means so that said first vibrating means receives alternate half waves of the alternating current having a second polarity, and a third mode for open circuiting said second vibrating means.

15. The vibration producing system of claim 14 wherein said rectifying means comprises a full wave rectifier having input terminals adapted to be connected to an alternating current supply and a pair of output terminals, said first means being operative in its first mode for connecting said first vibrating means to said output terminals, said second means being operative in its first mode for connecting said second vibrating means to said output terminals.

16. The vibration producing system of claim 15 wherein said first means comprises a first switch and said second means comprises a second switch.

17. The vibration producing system set forth in claim 16 wherein said first and second vibrating means comprises vibrating motors.

18. A method of controlling the level of energy supplied to a pair of vibrators coupled to an article of furniture for imparting vibrations in spaced apart locations to a user mounted thereon, comprising the steps of, selectively supplying one of the vibrators with either full wave rectified current from an alternating current source for generating a first level intensity, a half wave of the alternating current having a first polarity for generating lower vibration intensity than said first level or open circuiting the one vibrator, selectively supplying the other vibrator with either full wave rectified current from the alternating current source to provide a level of vibration intensity substantially equal to said first level, a half wave of the alternating current source and having a different polarity for providing a lower level of vibrating intensity than said first level, or open circuiting the second vibrator, whereby the full wave rectified current is utilized when both of said vibrators are either set for high vibration intensity or low vibration intensity.