GB2512881A

GB2512881A - A fall alarm comprising a ball switch

Info

Publication number: GB2512881A
Application number: GB1306455.5A
Authority: GB
Inventors: Robert Cheetham
Original assignee: Individual
Current assignee: Individual
Priority date: 2013-04-10
Filing date: 2013-04-10
Publication date: 2014-10-15
Also published as: GB201306455D0

Abstract

A fall alarm device is provided comprising an alert means, and a detector adapted to sense movement of the detector from a first upright position to second position. The detector comprises a channel and a conductive ball free to move within the channel. The detector further comprises a first contact provided on a first wall of the channel and a second contact spaced apart from the first wall and provided on a second wall of the channel. Following said movement, the conductive ball moves to make contact with the first and the second contacts. The detector further comprises an electric circuit adapted to sound the alert means when said contact is made. The device is particularly suited for warning of a fall by an elderly or infirm person. The device may be retrofitted to a walking aid such as a walking stick (see figure 1).

Description

A fall alarm comrisinp a ball switch

Field of the Invention

The present invention relates to devices to warn of a fall by an elderly or infirm person, and in particular to a fall alarm device that can be fitted to an existing walking aid such as a walking stick.

Background

A variety of device exist in the prior art to warn of a fall by an old or infirm person, many of which use tOt detection means to detect when the person or a walking aid such as a walking stick or walking frame used by the person tilts from the vertical.

Some prior art devices use mercury tilt switches or mercury within a specific housing.

These have the disadvantage of regulatory concerns surrounding mercury in consumer products and are also highly sensitive -in some cases too sensitive for situations where momentary tilting needs to be distinguishes from a genuine fall. Ball switch device are known, in which a heavy conductive ball moves from a rest position to make contact between a pair of contacts when the device tilts. These have the advantage of a slower response, and need a more positive fall or tilt to actuate them, so provide a more usable alarm means, but prior art devices have deficiencies of design that render them less reliable or more difficult to manufacture than need be.

Many prior art devices are also adapted to be built in to a walking stick or frame and are not retro-fittable.

It is an aim of the present invention to provide a more reliable fall alarm based on ball switch technology that is capab!e of lower cost manufacture. It is a further object to provide a fall alarm that may be fitted onto an existing walking aid such as a walking stick or frame.

Prior Art

Accordingly a number of patent applications have been filed in an attempt to resolve the problem or similar, including the following: CN202422358U discloses a fall alarm having a steel ball detector mechanism in which when the detector is tiled the ball rolls onto a pair of parallel contact strips in an arcuate chamber, so making contact between them and sounding the alarm. The strips are slightly raised from the side circumference edge of the chamber at a distance from the end of the chamber against which the ball comes to rest. A retaining lip is provided over which the ball travels when the detector is tilted that then acts to retain the ball in place on the pair of contacts.

This device has the disadvantage that the ball is not self-centring on the contacts and needs other shaped components to position it on the contacts, and the ball needs to travel over the retaining lip so needs a certain minimum amount of velocity in order to do so, so the device will be insensitive other than to a violent fall, for example failing to alarm if a person sinks to the ground and then cannot get back up. It is clear from the drawings of this disclosure that if the detector is rocked backwards there is the possibility that the ball will move back over the lip, so potentially cancelling the alarm.

This device represents a relatively crude ball mechanism detector over which the present invention provides a number of improvements. Also, it is not adapted to fit to a walking aid such as a walking stick.

CN202286650U discloses a walking stick of auto-alarm composed of the walking stick, battery and miniature power switch, the mercury cut-off, buzzer, LED and limiting resistor, the miniature power switch, buzzer and LED inlay to install on the walking stick. In the walking stick pole has a cavity, in the cavity the installment has the mercury cut-off, battery and limiting resistor. When the angle between the walking stick the ground is smaller than 45 degrees the mercury cut-off switch will close the circuit. When the old person using the walking stick goes out, they first close the power switch; when out, once the old person tumbles or has an accident to pass out, the walking stick will fall. At this time, the buzzer will sound and two red LED5 will simultaneously flash.

This disclosure is typical of many devices using a mercury tilt switch to provide a fall alarm detector, the switch and alarm being built in to the walking stick.

DE202004004170 discloses an alarm triggering switch that is intended to be worn on such as an infirm person to detect if the person leaves bed. The switch has a contact ball that is normally in a side channel. When moved to a vertical orientation the ball falls into a side channel and engages bridging contacts connected to an alarm.

This device uses a ball contact detector in which the ball must fall into a narrow channel in order to sound the alarm. The design of the device is such that the movement of the ball needs to be very specific in order for the alarm to sound -the shape of the ball track is such that in practice it is likely that the ball will stick and not reach the side channel.

Summary of the Invention

According to the present invention there is provided a fall alarm device comprising: an alarm means' a detector adapted to sense movement of the detector from a first upright position to second position, in which said detector comprises: a channel; a conductive ball free to move within the channel; a first contact provided on a first wall of the channel and a second contact spaced apart from the first and provided on a second wall of the channel; wherein following movement from the first upright position the conductive ball moves to make contact with the first and the second contacts, and an electric circuit adapted to sound the alarm means when said contact with the first and second contact is made.

Preferably the first wall is provided at an angle to the second wall. In a preferred embodiment the angle is substantially a right angle. In further preferred embodiments the angle is less than 90 degrees, more preferably in the range 45 to degrees.

Preferably the channel is in the form of an annulus.

In an alternative embodiment the channel is in the form of a tapered cylinder.

In a preferred embodiment at least one of the first and the second contacts is ring shaped and disposed around the circumference of the channel.

Preferably the first and the second contacts each extend substantially along the whole length of the channel.

In a preferred embodiment the first contact comprises a truncated conducting conical S surface and the second contact comprises a planar conductor.

Preferably the detector further comprises a ball locating recess opening to the channel within which the ball is adapted to lie when the detector is upright.

In a preferred embodiment the ball locating recess comprises a sidewall opening substantially at a right angle to a wall of the channel.

In a further preferred embodiment the channel comprises a hollow truncated conical shape and the ball locating recess comprises two or more projections extending from the inside surface of the channel.

In preferred embodiments the fall alarm device is adapted to fix to the exterior of a walking aid.

In this way, in use attached to a walking aid such as a walking stick, when the stick, and hence the detector, is upright the ball lies within the locating recess. When the stick is tilted the ball moves out from the recess into the channel. The ball then falls towards the outer edge of the channel, where it comes into contact with the first and the second walls of the channel at or near the outer edge of the channel. In doing so the ball comes into contact with the first and the second contact provided on the first and the second walls, so making contact between them and activating the alarm means.

In preferred embodiments the first and the second walls, and hence the first and the second contacts provided on the walls, are disposed at an angle one to another such that in use the ball falls into the groove formed by the angled walls and, is supported by the first and second contacts. In this way the ball makes a positive contact with the contacts and subsequent movement of the stick while it is tilted, such as sideways movement, shock or impact, will cause the ball to roll within the groove and still to maintain contact.

In preferred embodiments the channel comprises cylinder having a first face and a tapered outside edge at an acute angle to the first face wherein the first contact is disposed around the tapered outside edge and the second contact is disposed on the first face of the cylinder.

In this way the groove is formed by the first and the second contacts having an acute angle between them, the ball being supported by the first and the second contacts within the groove when the detector is tilted.

In preferred embodiments the conductive ball is a metal ball. The metal ball maybe solid or a hollow shell, and may comprise a conductive coating or shell overlying a non-conductive interior.

Preferably the channel and the ball location recess are adapted such that the ball rests within the ball location recess when the device is horizontal and exits the ball location recess when the detector is tilted to a given angle from horizontal. In a preferred embodiment the detector is adapted such that the said angle lies between degrees and 90 degrees.

Preferably the device further comprises attachment means adapted to attach the device to a walking aid such as a walking stick or frame. In preferred embodiments the attachment means comprises clamp means adapted to tighten around a substantially cylindrical object such as a walking stick or a tube forming part of a frame.

In preferred embodiments the device further comprises an on/off switch and a battery connected to the detector and alarm means. Preferably the device comprises a housing having the detector, battery and alarm means provided within the housing and the on/off switch mounted on the upper surface of the housing.

In preferred embodiments the alarm means comprises one or more of an audible alarm, a visual alarm and a remote alarm comprising RF communication, for example by mobile phone network. In a preferred embodiment the audible alarm comprises a pre-recorded message.

According to a further aspect the invention provides a method to give an alarm when a person falls comprising the steps of: providing an alarm device as described herein; attaching the alarm device to a walking aid: and powering the alarm device, such that the alarm sounds when the walking aid tilts.

Brief Description of Figures

Figure 1 shows an embodiment of a device according to the invention mounted on walking stick; Figure 2 shows a top view of the embodiment shown in figure 1; Figure 3 shows an isometric view of the embodiment shown in figure 1; Figure 4 shows an exploded view of the embodiment shown in figure 1; Figure 5 shows a cross sectional view of the embodiment shown in figure 1 in a horizontal orientation; Figure 6 shows a cross sectional view of the embodiment shown in figure 5 tilted through 90 degrees to a vertical orientation; and Figures 7 show views from above, below and a cross-section of a second embodiment of the device according to the invention.

Detailed Description of Figures

Referring to figures ito 6: An embodiment of a device according to the invention comprises a detector 10 adapted to sense movement of the detector from a first upright position to second position, the detector comprising: An alarm means, for example comprising one or more of an audible alarm 48 and a visual alarm 52, a channel 60, a conductive ball 44 free to move within the channel, a first contact 40 provided on a first wall 22 of the channel and a second contact 42 spaced apart from the first and provided on a second wall 62 of the channel, wherein following said movement the conductive ball moves to make contact with the first and the second contacts, and An electric circuit adapted to sound the alarm means when said contact is made.

In the embodiment shown the first wall 22 is provided at an angle to the second wall 62 of approximately 45 degrees. The embodiment does not depend on a precise angle and the angle may be for example substantially a right angle, or less than 90 degrees, or in the range 45 to 90 degrees. 5.

In this embodiment the channel is in the form of a tapered cylinder and the first and the second contacts each extend substantially along the whole length of the circumference of the channel, the first contact 40 comprises a truncated conducting conical surface and the second contact 42 comprising a planar conductor.

The detector further comprises a ball locating recess 64 opening to the channel within which the ball is adapted to lie when the detector is upright, as shown in figure 5, the channel comprising a hollow truncated conical shape and the ball locating recess comprising two or more projections 34 extending from the inside surface 22 of the channel.

In this way, in use attached to a walking aid such as a walking stick, when the stick, and hence the detector, is upright the ball lies within the locating recess. When the stick is tilted the ball moves out from the recess into the channel. The ball then falls towards the outer edge of the channel as shown in figure 6, where it comes into contact with the first and the second walls of the channel at or near the outer edge of the channel. In doing so the ball comes into contact with the first and the second contacts, so making contact between them and activating the alarm means.

In preferred embodiments the first and the second walls, and hence the first and the second contacts provided on the walls, are disposed at an angle one to another such that in use the ball falls into the groove 66 formed by the angled walls and is supported by the first and second contacts as shown in figure 6. In this way the ball makes a positive contact with the contacts and subsequent movement of the stick while it is tilted, such as sideways movement, shock or impact, will cause the ball to roll within the groove and still to maintain contact.

Referring to figures ito 4, an embodiment an alarm device according to the invention comprises a detector 10 and a clamp means 14, shown mounted on a walking stick 12. The device comprises a housing 16 comprising a housing upper portion iS and a lower portion 20, the housing lower portion being in the form of a truncated conical shell and having an internal surface 22, an external surface 24, a base 26 and a rim 30. A circumferential region 28 is present on the inner surface adjacent to the rim.

The upper portion 16 has a rim 32 sized to match the rim 30 of the lower housing portion. The lower housing portion has guide ribs 34 provided on the inner surface and clip means 36 to hold the upper and lower portions together.

*The device comprises a component housing insert 38 adapted to house circuit components and a first contact in the form of a metal ring 40 having the shape of a truncated conical shell and dimensioned to mount on the circumferential region 28 of the inner surface 22 of the lower housing portion. A second contact 42 (not visible in figure 4) is provided on the underside of the component housing insert 38 such that when the component housing insert is assembled within the housing the second contact is spaced apart from the first. Preferably the second contact comprises a metal contact ring mounted on the underside of the component housing insert and extending to a distance shod of the circumference of the component housing insert.

A conductive metal ball 44 is provided within the lower housing portion and contained within it by the component housing insert 38 when this is mounted into the housing.

A PCB 46 is mounted on the component housing insert and comprises and connects one or more circuit components including a preferably rechargeable battery 50 and some or all of a loudspeaker or audible alarm device 46, an alarm LED array 52, and power on and low battery indicators 54, 56. An on/off switch 58 is provided on the upper surface of the upper housing portion 18.

With reference to figures 7 the ball locating recess 64 opens to the channel 22 in a graded, rounded or arcuate fashion so as to allow natural and incremental movement of the ball 44, so that the ball can run free when the stick is dropped.

The invention has been described by way of examples only and it will be appreciated that variation may be made to the above-mentioned embodiments without departing from the scope of invention.

With respect to the above description then, it is to be realised that the optimum dimensional relationships for the parts of the invention, to include variations in size, materials, shape, form, function and manner of operation, assembly and use, are deemed readily apparent and obvious to one skilled in the art, and all equivalent relationships to those illustrated in the drawings and described in the specification are intended to be encompassed by the present invention.

Therefore, the foregoing is considered as illustrative only of the principles of the invention. Further, since numerous modifications and changes will readily occur to those skilled in the art, it is not desired to limit the invention to the exact construction and operation shown and described, and accordingly, all suitable modifications and equivalents may be resorted to, falling within the scope of the invention.

Claims

Claims 1. A fall alarm device comprising: an alarm means; a detector adapted to sense movement of the detector from a first upright position to second position, in which said detector comprises: a channel; a conductive ball free to move within the channel; a first contact provided on a first wall of the channel and a second contact spaced apart from the first wall and provided on a second wall of the channel; and wherein following said movement the conductive ball moves to make contact with the first and the second contacts; and an electric circuit adapted to sound the alarm means when said contact is made.
2. A fall alarm device as claimed in claim 1 wherein the first wall is provided at an angle to the second wall.
3. A fall alarm device as claimed in claim 2 wherein the angle is substantially a right angle.
4. A fall alarm device as claimed in claim 2 wherein the angle is less than 90 degrees
5. A fall alarm device as claimed in claim 2 wherein the angle is in the range 45 to 90 degrees.
6. A fall alarm device as claimed in any claim above wherein the channel is in the form of an annulus.
7. A fall alarm device as claimed in any claim above wherein the channel is in the fOrm of a tapered cylinder.
8. A fall alarm device as claimed in any claim above wherein at least one of the first and the second contacts is ring shaped and disposed around the circumference of the channel.
9. A fall alarm device as claimed in any claim above wherein the first and the second contacts each extend substantially along the whole length of the channel.
10. A fall alarm device as claimed in any claim above wherein the first contact comprises a truncated conducting conical surface and the second contact comprises a planar conductor
11. A fall alarm device as claimed in any claim above wherein the detector further comprises a ball locating recess opening to the channel within which the ball is adapted to lie when the detector is upright.
12. A fall alarm device as claimed in any claim above wherein the ball locating recess comprises a sidewall opening substantially at a right angle to a wall of the channel.
13. A fall alarm device as claimed in any of claims 1 to 11 wherein the channel comprises a hollow truncated conical shape and the ball locating recess comprises two or more projections extending from the inside surface of the channel.
14. A fall alarm device as claimed in any claim above wherein the first and the second walls are disposed at an angle one to another such that in use the ball falls into the groove formed by the angled walls and is supported by the first and second contacts.
15. A fall alarm device as claimed in any claim above wherein the channel comprises a cylinder having a first face and a tapered outside edge at an acute angle to the first face wherein the first contact is disposed around the tapered outside edge and the second contact is disposed on the first face of the cylinder.
16. A fall alarm device as claimed in any claim above wherein the ball location recess is adapted such that the ball rests within the ball location recess when the device is horizontal and exits the ball location recess when the detector is tilted to an angle from horizontal.
17. A fail alarm device as claimed in claim 16 wherein the said angle lies between degrees and 90 degrees.
18. A fall alarm device as claimed in any claim above further comprising attachment means adapted to attach the device to a walking aid such as a walking stick or frame. -
19. A fall alarm device as claimed in claim 18 wherein the attachment means comprises clamp means adapted to tighten around a substantially cylindrical object such as a walking stick or a tube forming part of a frame.
20. A fall alarm device as claimed in any claim above further comprising a housing having the detector, battery and alarm means provided within the housing and an on/off switch mounted on the upper surface of the housing.
21. A fall alarm device as claimed in any claim above comprising one or more of an audible alarm, a visual alarm and a remote alarm comprising RF communication.
22. A method of giving an alarm when a person falls comprising the steps of providing an alarm device as described herein, attaching the alarm device to a walking aid, and powering the alarm device, such that if the person falls and the walking aid tilts then the alarm is sounded.