WO1986003388A1

WO1986003388A1 - Method and device for reducing the risk of disturbing noise from small children

Info

Publication number: WO1986003388A1
Application number: PCT/SE1985/000501
Authority: WO
Inventors: Karl Gustaf ROSÉN
Original assignee: Rosen Karl Gustaf
Priority date: 1984-12-10
Filing date: 1985-12-04
Publication date: 1986-06-19
Also published as: SE8406250D0; US5003651A; DE3590637C2; GB2168604A; SE458414B; SE8406250L; DE3590637T; GB2168604B; GB8527811D0; AU592967B2; US4893366A; AU5234986A

Abstract

The risk of disturbance from children's cries is reduced if the child is subjected to mechanical vibration. This is applied to the child's place of rest by the use of a motor with imbalance. The environmental inconvenience caused by the children's cry is eliminated usually by a vibration frequency which is disturbing in itself but which is attenuated in a knownway at the place of rest's contacts with the surroundings. An automatic device for starting when the child cries can be applied.

Description

FROM SMALL CHILDREN

TECHNICAL FIELD

Cries from children can be tolerated by parents of the children. Neighbours however consider crying children a disturbance and the noise a health hazard. Inspections on site often indicate poor wall or floor insulation. The present invention attacks the source of noise and reduces considerably the risk of disturbance.

BACKGROUND ART

The cradle has been in use since ancient times. Parents have found that a slow periodic movement has a pacifying effect on the child as a whole. The periodicity of these movements has normally been within the range of up to 50 cycles per minute. It has not been possible to achieve higher frequencies with cradles or hanging baskets.

For a general feeling of well-being, complete beds have been deve¬ loped which have been made to vibrate through som form of imbalance.

At motels, particularly in the USA, there are various devices with coin meters but these devices also have a relatively low frequency. It has been observed that discomforting vibrations have been trans¬ mitted through the buildings.

Empirically it has been found that vibrations have a tension-relea¬ sing effect on the human body. Vibration massage has long been a method applied. The vibrations are attenuated by the body being treated, and are not transmitted to the surrondings. The same is found with the sexual vibrators which have found a considerable market of late. Even here the empirical result from ancient time has now appeared in a modern form.

Modern research, particularly on infants, indicates that the crying which can be observed during the years of infancy is caused by cramp in the intestines. Cramp leads to pain which in turn leads to the very typical crying of a child which may often have the character of an environmental invonvenience - albeit temporary. The present invention is therefore directed to diverting the cause of irritating noise from small children. Knowledge about cramp pro¬ vides the solution where children should be subjected to types of vibrations which relieve the attacks of cramp. It has been found particularly suitable in this context that the frequency used for treatment should be in the region of 800 - 2000 vibrations per minute. The purely technical problem is subjecting the child's in¬ testines to a pulsating mechanical load while at the same time preventing this pulsating movement from being transmitted to the surroundings as an environmental invonvenience of a type other than a child's crying.

DISCLOSURE OF THE INVENTION

The concept according to this invention means that the child's place of rest, which may be a bed or a perambulator, is subjected to vibrations from some form, of vibrator. Since the child as such cannot be treated directly and the intention is to gain the greatest possible degree of efficiecy without disturbing the environment, a small motor is used. Despite this, vibrations still occur outside the area of rest. The result of the invention must be that these vibrations are attenuated. Thus the present invention includes the addition of attenuation with respect to the surroundings. In purely mechanical terms this means that the place of rest is placed on an attenuating base.

MODE FOR CARRYING OUT THE INVENTION

A suitable bed for a child below the age of six months was found.

When the child had been given food and burped, a routine was deve- loped so that the child would go to bed. A small motor was attached to the edge of the bed. The motor had an output of 7 watts and a rotational speed of 1400 revolutions per minute. A circular disc of plastic with an oval hole was fitted to the motor with one end of the oval hole at the centre of the circular disc. The disc was attached to the threaded axle of the motor with a standard nut.

The attachment was made so that the disc's centre was located to one side of the centre of the axle. When the motor, which was connected to the mains, was started, the bed began to vibrate at the same frequency as the motor's speed. If this motor was started after the child had eaten, the child appeared to be quite happy and hardly any crying occured. However if the motor was not started, a heart-rending noise was heard from the child approximately 30 minutes later which clearly indicated that the child did not feel well.

Previous attempts to reduce the noise from the child by carrying it around usually produced poor results. The family and the neigh¬ bours were regularly disturbed by a child's heart-rending cries after each meal. The parents found that the immediate neighbours often looked at them in a particular way as though the parents were obviously mistreating their child. However the use of the motor made the child quiet.

But the quietness of the child was at the cost of a new inconve¬ nience. It was found that the natural frequency of the bed led to an amplification of the noise from the bed's vibrations. Even this noise had the character of an environmental inconvenience but the solving of this particular problem was simple.

The bed was placed on a soft base. Experiment showed that poly- urethane foam plastic provided the best attenuation if each leg was placed in a special foot of urethane foam. However this was not always sufficient since sometimes the side of the bed came in contact with a wall and it was therefore found necessary to provide an attenuating layer of urethane foam between points where the bed could be expected to come in contact with adjacent walls and floor of the house.

By suitable standard adaptions of the motor's attachment it could be applied not only to the child's bed but also to the perambulator in which the child normally slept outside on a balcony. Even the perambulator exibited the pheno en of natural frequency and it was found necessary to reduce interference from the perambulator with polyurethane foam between the perambulator and its surroundings. Soft wheels also provided good attenuation.

In this particular successful test of invention's application it was found to be very useful to have the rotating plastic disc provided with an oval hole. Different underlays in the child's place of rest were found to have different degrees of attenuation. For the bed, in particular, a somewhat greater imbalance was needed than for the perambulator, when the child had eaten, to avoid disturbing cries.

Experiments with other motors indicated that a vibration fre¬ quency that was to low did not have an attenuating effect on the child's cries. It was not until a speed which exceeded 800 revs. per minute occured in the imbalance that it began to have an attenuating effect on the environmental inconvenience caused by children's cries. At a frequency above 2000 revs, per minute it was found that the base at the child's place of rest attenuated the effect -o that the vibrations did not reach the actual souce of the noise, namely the child. At these higher frequencies children's cries occured as though the invention were not being used..

Within the interwal tested for vibration frequencies there is a range of frequencies which is very easy to transmit throughout a building. Even if the child's cry reaches the level of an enviro- mental inconvenience it is inappropriate to remove one sorce of noise and then introduce another. Thus the reduction of interfernce at the child's place of rest is therefore a necissity and a sig¬ nificant part of the invention. The actual attenuating device's design is something that every person skilled in the art could produce. The amount of mass in movement is very small, child plus place of rest, and very soft material can be used. So far, poly- urethane has been found to produce the best effect but this does not exclude the use of other attenuating devices since these fall within the framework of subsequent patent claims in a natural manner.

Where there has been no access to electrical power a simple echan- cal spring-operated mechanism has provided good results for atte¬ nuating children's cries. It has been possible to wind the spring up to produce a given operating time depending on the tension of the spring. This has also been found to provide a very economic device. Every person skilled in the art will easlily understand that the imbalance does not necessary need to be attached to the actual motor axle but can also be connected to some other driven axle. Such persons will also understand that the electrically-driven equipment can be provided with standard automatic devices for starting at given time and stopping after a certain period of use.

To further automate the device for attenuating children's cries, the actual device can be fitted with a microphone which at a certain noise level, from a child for example, starts the cry-attenuating device and starts the vibration of the child's place of rest. This type of equipment is well known to every person skilled in the art. However, the child's cries may not cease despite the use of auto¬ matic switching of the vibration device. This may have a natural explanation in the child being wet. In such cases, an additional alarm in the form of a visual or audible signal can be actuated after a certain amount of running time of the vibration device where the alarm, in such cases attracts the attention of the person caring for the child, for example at a hospital.

INDUSTRIAL APPLICABILITY The noise can cause an environmental inconvenience particularly in housing. This has a detrimental effect on the occupant's per¬ formance and thus has a disadvantageous effect on the national economy. Thus an environmental inconvenience is an evil. If this is caused by noise, there are two possible solutions. Either the noise is prevented from being transmitted within a building, which is unnecessarily expensive in many cases, or one can counteract the source of the noise.

The present invention illustrates a method and a device for com¬ batting children's cries by introducing vibrations, which in them- selves have an interfering effect on the child's place of rest. The invention means that even this interference is attenuated with ure¬ thane foam or similar device. Thus the invention means that inter¬ ference with a number of different interference frequencies is counteracted with a frequency where the latter's transmission through a building is carefully attenuated in the vicinity of the source.

Claims

1. A method of reducing the risk of interfering noise and parti¬ cularly cries from small children c h a r a c t e r s e d i n that the child's place of rest such as its bed or perambulator, is subjected to mechanical vibrations in a known way and at the same time the child's place of rest, at all fixed positions of contact with the surroundings, is supported by soft vibration-attenuating layers.

2. A method according to Claim 1 c h a r a ct e r i s e d in that the vibrations are generated by an electric motor with one or more imbalances on its axle or other axles which are mechanically joined to the axle.

3. A method according to Claim 2 c h a r a c t e r i s e d i n that the motor generates a vibration frequency within the range 800 - 2000 revs, per minute.

4. A device for reducing the risk of disturbing noise and parti¬ cularly cries from small children c h a r a c t e r i s e d i n that the same comprises a driven motor with an imbalance, which in a known way is attached to the child's place of rest e.g. its bed or perambulator, and known vibration-attenuating devices at the place of rest's mechanical contact with the surroundings.

5. A device according to claim 4 c h a r a c t e r i s e d i n that the motor is electrically driven.

6. A device according to claim 5 c h a r a c t e r i s e d i n that the vibrations are generated by one or more imbalances which in a known wqy are attached to the motorIs axle.

7. A device according to claim 4 c h a r a c t e r i s e d i n that the motor's speed is in the range 800 - 2000 revs, per minute.

8. A device according to Claim 4 c h a r a c t e r i s e d i n that the motor's start is controlled in a known way by the sound level from the crying child.

9. A device according to Claim 4 c h a r a c t e r i s e d i n that an additional alarm is started in a known way if the noise level from the child has not decreased to below a predetermined le level after a preset time.

10. A device according to Claim 4 c h a r a c t e r i s e d i n that the imbalance is provided by a mechanical device with spring tension