GB2560984A

GB2560984A - A rocking device

Info

Publication number: GB2560984A
Application number: GB1705215.0A
Authority: GB
Inventors: Andrew Webb Nicholas; Richard Dyson Matthew
Original assignee: N2m Ltd
Current assignee: N2m Ltd
Priority date: 2017-03-31
Filing date: 2017-03-31
Publication date: 2018-10-03
Anticipated expiration: 2037-03-31
Also published as: WO2018178703A1; GB2560984B; GB201705215D0

Abstract

Disclosed is a device 2 suitable for rocking prams, pushchairs or the like. The device comprises a motor 18, an axle 26 connected to the motor, a weight 30 eccentrically connected to the axle, and a speed controller connected to the motor. The speed controller drives the motor to rotate the weight at a set rocking frequency between 2 and 10Hz. The speed controller comprises a speed boost function that increases the speed of the motor above the set rocking frequency for an initial period of operation to overcome the inertia of the weight, with the speed reducing to match the set rocking frequency after the initial period. The speed controller may comprise an adjuster for varying the rocking frequency. The output shaft of the motor may comprise a drive pulley 22, and the weight may be connected to the axle via a driven pulley 24, said driven pulley having a larger diameter than the drive pulley.

Description

(54) Title of the Invention: A rocking device

Abstract Title: Rocking device comprising an eccentric weight and a controller with a speed boost function (57) Disclosed is a device 2 suitable for rocking prams, pushchairs or the like. The device comprises a motor 18, an axle 26 connected to the motor, a weight 30 eccentrically connected to the axle, and a speed controller connected to the motor. The speed controller drives the motor to rotate the weight at a set rocking frequency between 2 and 10Hz. The speed controller comprises a speed boost function that increases the speed of the motor above the set rocking frequency for an initial period of operation to overcome the inertia of the weight, with the speed reducing to match the set rocking frequency after the initial period. The speed controller may comprise an adjuster for varying the rocking frequency. The output shaft of the motor may comprise a drive pulley 22, and the weight may be connected to the axle via a driven pulley 24, said driven pulley having a larger diameter than the drive pulley.

1/6

FIG. 1

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FIG. 2

3/6

FIG. 3

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14,

FIG. 4

5IQ

FIG. 5

QIQ

FIG. 6

A ROCKING DEVICE

The invention relates to a rocking device which may be used to generate a rocking motion in prams, pushchairs, cribs and the like.

It has been shown that the gentle rocking of a pram, pushchair or crib is effective in helping to soothe a baby so as to encourage them to fall and stay asleep. However, it can be difficult to maintain this action when performed by hand, particularly when undertaking other tasks. This has led to the development of automatic devices which are intended to recreate this motion. Nevertheless, there still remains a need for a device which is capable of rocking a broad range of baby sleeping apparatuses and is easily transferrable between such apparatuses.

In accordance with an aspect of the invention, there is provided a rocking device comprising: a motor; an axle connected to the motor; a weight eccentrically connected to the axle for rotation by the motor; and a speed controller connected to the motor; wherein the speed controller is configured to drive the motor so as to rotate the weight at a set rocking frequency of between 2 to 10Hz thereby generating a centripetal force which causes the device to oscillate; and wherein the speed controller comprises a speed boost function which increases the speed of the motor such that it is greater than the set rocking frequency for an initial period of operation in order to overcome the inertia of the weight, with the speed reducing after the initial period to match the set rocking frequency.

The speed controller may comprise an adjuster for varying and setting the rocking frequency.

The speed controller may be configured such that the speed boost function is only provided if the rocking frequency set using the adjuster is below a threshold frequency.

The speed boost function may increase the speed of the motor such that it is greater than a speed of the motor when the adjuster is set to provide a maximum rocking frequency.

The initial period of operation may be greater than 0 and less than 1 second.

The initial period of operation may be % second.

An output shaft of the motor may be connected to a drive pulley and the weight may be connected to the axle via a driven pulley, the drive pulley and driven pulley being connected by a belt and the driven pulley having a larger diameter than the drive pulley.

For a better understanding of the invention, and to show more clearly how it may be carried into effect, reference will now be made, by way of example, to the accompanying drawings, in which:Figure 1 is a perspective view of a rocking device according to an embodiment of the invention;

Figure 2 is an exploded view of the rocking device showing a rocking mechanism and control module;

Figure 3 is an exploded view of the rocking mechanism;

Figure 4 is an enlarged view of the rocking mechanism;

Figure 5 is an exploded view of the rocking device showing the mounting for the rocking mechanism; and

Figure 6 is a perspective view of the rocking device showing the rocking mechanism mounted within the device.

Figure 1 shows a rocking device 2 according to an embodiment of the invention. As shown, the rocking device 2 generally has the form of a space rocket (although other forms may be used) having a prolate spheroid or ovoid shaped body 4 and a plurality (three, in this instance) of fins 6 which project from a lower part of the body 4. The body 4 of the device is provided with an attachment portion 8, such as a clip or strap, which may be used to attach the device to a baby sleeping apparatus, such as a pram, pushchair, crib or the like. An upper point of the body 4 is provided with a power button 10 for switching the device 2 on and off. In this embodiment, the power button 10 is a latching push button switch. A lower point of the body 4 is provided with an adjuster knob 12 which will be described in more detail below. The fins 6 may be used to support the device 2 in a vertical orientation and provide protection to the adjuster knob

12.

As shown in Figure 2, the body 4 is formed as two separable parts, an upper portion 4a comprising the power button 10 and a lower portion 4b comprising the adjuster knob 12. The body 4 defines an internal cavity which is accessible by separating the upper and lower portions 4a, 4b of the body 4. The body 4 thus forms a housing which contains the components of the device 2. The upper and lower portions 4a, 4b of the body 4 may be interconnected so as to seal the housing and prevent water ingress. Specifically, as shown, the device 2 generally comprises a rocking mechanism 14 and a control module 16 connected to the rocking mechanism 14.

Figures 3 and 4 show the rocking mechanism 14 in detail. The rocking mechanism 14 comprises an electric DC motor 18 having an output shaft 20. A drive pulley 22 is provided on the output shaft 20 of the motor 18. A driven pulley 24 is mounted on an axle 26 and is connected to the drive pulley 22 by a belt 28. The driven pulley 24 carries a weight 30 which is affixed to the driven pulley 24 via a carrier 32. The weight 30 is in the form of a circular sector whose centre is coaxial with the axle 26. The centre of mass of the weight 30 is therefore offset from the axle 26 such that the weight 30 is eccentrically mounted about the axle 26.

As shown in Figures 5 and 6, the motor 18 is held within a housing formed in the upper portion 4a of the body 4 with the output shaft 20 projecting downwards towards and into the lower portion 4b. The upper portion 4a further houses a power source (not shown) such as one or more batteries (e.g. four AA batteries) which are connected to contacts of the motor 18. The power source may be rechargeable either in-situ or after removal from the device 2. The upper portion 4a further comprises an upper axle support 34 rotatably supports an upper end of the axle 26 within an opening formed in the upper axle support 34. As shown in Figure 2, a lower axle support plate 36 is located in the lower portion 4b of the body 4. The lower axle support plate 36 is supported within the lower portion 4b upon a plurality of posts 38. The posts 38 support the lower axle support plate 36 above the control module 16 which is located within the lower portion 4b. The lower axle support plate 36 comprises an opening which is aligned with the opening of the upper axle support 34 and rotatably supports a lower end of the axle 26.

The control module 16 comprises a speed controller (in this example, a digital speed controller) formed on a circuit board and having a potentiometer 40 which is provided on a lower surface of the circuit board. A shaft of the potentiometer 40 extends from the interior of the body 4 to the exterior through an opening in the lower portion 4b. The adjuster knob 12 is provided on the shaft to allow adjustment of the potentiometer.

The speed controller allows the speed of rotation of the motor 18 and thus the weight 30 to be varied. The driven pulley 24 is larger than the drive pulley 22 and thus provides a mechanical advantage. The speed controller is configured to control the motor 18 (via wires that pass from the speed controller to the motor 18 and which are not shown) such that the weight 30 rotates at a frequency of between 2 to 10Hz and preferably between 4 to 8Hz. As described previously, the centre of mass of the weight 30 is offset from the axle 26. Consequently, rotation of the weight 30 generates a centripetal force which causes the device 2 and the apparatus to which it is attached to rock or gyrate. In the specific embodiment, the weight has a mass of 88g and is offset from the axis of rotation by approximately 1.5cm. Accordingly, at a frequency of 2Hz, the weight 30 generates a centripetal force of 0.2N and at 10Hz generates a centripetal force of 6N. The device 2 provides a rocking motion which is of a relatively low speed and thus suitable to soothe a child, but has sufficient force to move the relatively heavy apparatus to which the device 2 is attached.

The control module 16 is configured to provide a speed boost function when the device 2 is initially activated (i.e. when the power button 10 is depressed). The speed boost function provides a short period where the speed of rotation of the motor is higher than that set by the potentiometer. For example, the potentiometer may be set to provide a frequency of 2Hz, but for the first ¹Λ second of operation the frequency is greater. After this initial period the speed is reduced to that set by the potentiometer. The speed boost function is provided to overcome the inertia of the weight 30. The device 2 is designed to be attached to any member on the pram, pushchair or crib and thus must operate at any angle. The inertia of the weight 30 is greatest when the device 2 is oriented horizontally. The speed boost function allows the device 2 to start when the device 2 is in the horizontal orientation and is set on the lowest speed.

The device 2 may be provided with an orientation sensor, such as a tilt sensor, which is able to detect the orientation of the device 2. The output of the orientation sensor may be used by the control module 16 to determine whether the device 2 is in an orientation which requires the speed boost function and only apply the speed boost function when in such an orientation (e.g. when the device 2 is horizontal or has an inclination which is below a predetermined threshold). The orientation sensor may therefore be used to avoid applying the speed boost function unless the device 2 is in a position where it is actually required and so can reduce battery consumption.

Although the rocking mechanism 14 has been described as utilising a belt and pulley arrangement, it will be appreciated that the speed boost function would be beneficial in overcoming the inertia of the weight 30 in other arrangements where the motor may drive the weight 30 directly or through some other gear mechanism. Having said that, the combination of the speed boost function and the belt and pulley arrangement is particularly advantageous in the rocking device. In particular, the mechanical advantage provided by the belt and pulley arrangement allows a small DC motor to provide sufficient torque to overcome the inertia of the weight 30. Such a motor is quiet in operation and thus does not disturb the child. In contrast, geared motors which could produce sufficient torque may be considered too noisy for this application.

It will be appreciated that the speed boost function may provide the speed increase for longer or shorter than % second. However, it is desirable to minimise the duration of the speed increase in order to conserve power and the duration may thus be kept below 1 second. The duration of the speed increase may therefore only be sufficient to overcome the inertia of the weight. The increased speed may still lie in the normal range of operation of the device such that the speed boost function is only utilised when the potentiometer 40 is set within a lower frequency range or is at the lowest frequency. For example, the speed boost function may increase the frequency to 5Hz. Consequently, the speed boost function may be employed when the potentiometer is set to provide a frequency which is less than 5Hz, but is not used nor required when the frequency is set at 5Hz or greater. The speed boost function may therefore override the frequency set by the potentiometer 40 when it is below a certain threshold. Alternatively, the speed boost function may increase the speed beyond that which is normally achievable via the potentiometer 40. In this instance, the speed boost function may be utilised when starting the device 2, regardless of the setting of the potentiometer 40.

It is not necessary that the device 2 be provided with means for a user to adjust the frequency of the rocking motion. Instead, the device 2 may have a single preset frequency which is considered to be the optimum frequency for providing a soothing rocking motion. The speed boost function may still be utilised with such a device to ensure that the motor 18 is able to overcome the inertia of the weight 30.

The control module 16 may further comprise a timing circuit which automatically deactivates the rocking mechanism 14 after a set time which may be configurable by the user.

The frequency ranges stated herein are given for when the device is in the vertical orientation and with fresh (i.e. non-discharged) alkaline batteries. The frequency may fall outside of the stated ranges when in the horizontal orientation (or any angle between horizontal and vertical) and/or when used with partially discharged batteries or other power sources, such as rechargeable NiMH batteries.

To avoid unnecessary duplication of effort and repetition of text in the specification, certain features are described in relation to only one or several aspects or embodiments of the invention. However, it is to be understood that, where it is technically possible, features described in relation to any aspect or embodiment of the invention may also be used with any other aspect or embodiment of the invention.

The invention is not limited to the embodiments described herein, and may be modified or adapted without departing from the scope of the present invention.

Claims

1. A rocking device comprising: a motor;

an axle connected to the motor;

a weight eccentrically connected to the axle for rotation by the motor; and a speed controller connected to the motor;

wherein the speed controller is configured to drive the motor so as to rotate the weight at a set rocking frequency of between 2 to 10Hz thereby generating a centripetal force which causes the device to oscillate; and wherein the speed controller comprises a speed boost function which increases the speed of the motor such that it is greater than the set rocking frequency for an initial period of operation in order to overcome the inertia of the weight, with the speed reducing after the initial period to match the set rocking frequency.

2. A rocking device as claimed in claim 1, wherein the speed controller comprises an adjuster for varying and setting the rocking frequency.

3. A rocking device as claimed in claim 2, wherein the speed controller is configured such that the speed boost function is only provided if the rocking frequency set using the adjuster is below a threshold frequency.

4. A rocking device as claimed in claim 2, wherein the speed boost function increases the speed of the motor such that it is greater than a speed of the motor when the adjuster is set to provide a maximum rocking frequency.

5. A rocking device as claimed in any of the preceding claims, wherein the initial period of operation greater than 0 and less than 1 second.

6. A rocking device as claimed in claim 5, wherein the initial period of operation is 1A second.

7. A rocking device as claimed in any of the preceding claims, wherein an output shaft of the motor is connected to a drive pulley and the weight is connected to the axle via a driven pulley, the drive pulley and driven pulley being connected by a belt and the driven pulley having a larger diameter than the drive pulley.

Intellectual

Property

Office

Application No: GB1705215.0 Examiner: Mr David Smitten