GB2422018A

GB2422018A - Scales for weighing people

Info

Publication number: GB2422018A
Application number: GB0500125A
Authority: GB
Inventors: Carol Ann Dodd; Paul Richard Dodd
Original assignee: Individual
Current assignee: Individual
Priority date: 2005-01-06
Filing date: 2005-01-06
Publication date: 2006-07-12
Also published as: GB0500125D0; WO2006072778A1

Abstract

Scales (10) for weighing a person comprise at least four platform portions (16A-D) that are hinged one to another for folding in two directions between an opened-up configuration (Figure 1) in which the platform portions are arranged in a two-dimensional array to form a platform (12) on which the person can stand and a folded-up configuration (Figure 3) in which the platform portions are arranged in a stack (58). Each platform portion has sensors for sensing the load applied to that portion when the portions are in the opened-up configuration. The scales further include sensor responsers for determining and indicating to the person the total load applied to the platform. Both the width and the length of the scales are reduced when the scales are placed in the folded-up configuration.

Description

TITLE

Scales for weighing people

DESCRIPTION

This invention relates to scales for weighing people.

(It should be noted that, in this context, the term scales' originally referred to an apparatus for measuring the mass of a person that relied upon balance between the person and a reference object of known mass, whereas the term is nowadays used also to refer to an apparatus for measuring the weight of a person that relies upon the measurement of strain or other parameters caused by the person's weight. In this specification, the latter, broader interpretation is intended unless the context requires otherwise.) Scales for enabling people to weigh themselves are, of course, well-known, and many families have a set of bathroom scales' in their bathroom, so that members of the family can keep an eye on their weight and adjust their diet, exercise routine and in some cases their medication accordingly. Some people have the need to keep a frequent watch on their weight, and a problem arises when they stay away from home if the place where they are staying does not have a set of scales. People could take their bathroom scales with them when they go away.

However, conventional bathroom scales are relatively bulky and heavy (for example, the author's conventional bathroom scales have a size of 0.26 m x 0.26 m x 0.05 rn and a mass of 1.4 kg) and can take up valuable luggage space and baggage weight allowance.

In a known development of conventional bathroom scales described in patent document US 47113 13, the shape of the scales can be reconfigured allegedly to make the scales convenient to carry In particular, patent document US 4711313 shows a number of versions of scales that are divided width-wise into two, three or four rigid portions that are hinged one to another for movement between an opened-up configuration in which the portions are arranged side by side in a line to form a platform on which a person can stand when the scales are used, and a folded-up configuration in which the portions are arranged in a stack or bundle.

The present invention provides scales for weighing a person, the scales comprising at least four platform portions that are hinged one to another for folding in two directions between an opened-up configuration in which time platform portions are arranged in a two-dimensional array to form a platform on which the person can stand and a folded-up configuration in which the platform portions are arranged in a stack, preferably a single stack, each platform portion having means for sensing the load applied to that portion when the portions are in the opened-up configuration, and the scales further including means responsive to the sensing means for determining and indicating to the person the total load applied to the platform. Like the scales of US 4711313, the width of the scales of the present invention is reduced when the scales are placed in the folded-up configuration. However, by contrast to the scales of US 4711313, the length of the scales of the present invention is also reduced when the scales are placed in the folded-up configuration.

The scales may have more than four platform portions. However, for reasons of simplicity of use and construction, there are preferably four platform portions (or quadrants), with the four platform portions being arranged in a two-by-two array when in the opened-up coiifiguration. The length of the platform can therefore be approximately halved, in addition to the width of the platform being approximately halved, when the scales are placed in the folded- up configuration.

When in the opened-up configuration, the width of the platform is preferably such that an adult can stand on the platform without the sides of their feet overhanging the edges of the platform to any significant extent, with their feet slightly apart so that they can stand steadily.

Preferably, the width of the platform is betweeii about 280 mm and about 350 mm when in the opened-up configuration. In the case of four platform portions, the width of the stack in the folded-up configuration can therefore be between about 140 mm and 175 mm or less.

When in the opened-up configuration, the length of the platform is preferably such that an adult can stand on the platform without the fronts and backs of their feet overhanging the edges of the platform to any significant extent Preferably, the length of the platform is between about 240 mm and about 280 mm when in the opened-up configuration. In the case of four platform portions, the height of the stack in the folded-up configuration can therefore be between about 120 mm and 140 mm or less.

Preferably, the platform portions are relatively thin, for example no more than about 10 mm thick, more preferably no more than about 8 mm thick, and even more preferably no more than about 6 mm thick. In the last case, and in the case of four platform portions, the height of the stack in the folded-up configuration can therefore be about 24 mm.

The means for determining and indicating the total load may be provided within one of the platform portions. However, especially when the load is indicated visually, the total load indicating means may be provided in a housing that is disposed to one side of one of the platform portions when the scales are in the opened-up configuration, and that is disposed alongside the stack when the scales are in the folded-up configuration. In this case, the height of the housing is preferably not substantially greater than the height of the stack when the scales are in the folded-up configuration.

As will be appreciated from the following detailed description, when the above- mentioned preferred features are combined, it is possible to realise scales that provide a good size of platform when in the opened-up configuration, and yet are of about the same size as a reasonably thick paperback novel when in the folded-up configuration.

Preferably, each platform portion comprises a base plate and a top plate, and the platform portions are hinged together by a flexible sheet that is sandwiched between each base plate and its respective top plate In this case, the means for sensing the load applied to each platform portion may comprise a group of electrical load sensors that are fixed to the flexible sheet and in use support the respective top plate above the respective base plate and electrical connections that are mounted on or in the flexible sheet and interconnect the load sensors.

Electrical connections may also be mounted on or in the flexible sheet to connect the groups of sensors to the means for determining and indicating the total load. The flexible sheet may be realised as a development of the known Flexiforce technology referred to later. Each sensor preferably has an electrical conductance or resistance that is proportional to the load applied to that sensor, in which case all of' the sensors may be electrically connected in parallel or series, as the case may he, and the means frr determining and indtcatng the total load may be operable to determine the resultant conductance or resistance, as the case may be, of the sensor circuit.

Specific embodiments of the present invention and some modifications thereto will now be described, purely by way of example, with reference to the accompanying drawings, in which: Figure 1 is an isometric view of a first embodiment of weighing scales in an opened-up configuration; Figure 2 is an isometric view of the weighing scales in a half-folded-up configuration; Figure 3 is an isometric view of the weighing scales in a folded-up configuration; Figure 4 is a sectioned elevation of' the weighing scales taken on the section line 4-4 shown in Figure 3 and at about four times the scale of Figure 3; Figure 5 is a sectioned elevation of the weighing scales taken on the section line 5-5 shown in Figure 3 and at about four times the scale of Figure 3; Figure 6 is a plan view of a sensor sheet used in the scales at about the same scale as Figures 1 to 3; Figure 7 is similar to Figure 6, but showing a modification to the sensor sheet; Figure 8 is a partial sectioned elevation of a corner of the scales taken on the section line 8-8 in Figure I at about eight times the scale of Figure 1; Figures 9 & 10 are similar to Figure 8, but showing modifications to the scales; Figure 11 is an isometric view of a second embodiment of weighing scales in an opened- up configuration; Figure 12 is an isometric view of the weighing scales of Figure 11 in a folded-up configuration; and Figure 13 is a plan view of a sensor sheet used in the scales of Figures 11 and 12.

Referring first to Figures 1 and 6, scales 10 comprise a weighing platform 12 and a display unit 14. The weighing platform 12 is arranged as four quadrants 16A-D. A flexible sensor sheet 18 extends across the four quadrants 16A-D and has a connector portion 19 extending to the display unit 14. In each quadrant 16A-D, a respective portion 20A-D of the sensor sheet 18 is sandwiched between a rigid, rectangular, plastics base plate 22A-D and a rigid, rectangular, plastics top plate 24A-D. Three of the base plates 22B-D and all of the top plates 24A-D are of similar size, whereas one of the base plates 22A is larger and has a portion 26 extending under the display unit 14 A rectangular hole 28 is formed generally in the centre of the sensor sheet 18, and the quadrants l6A-D of the platform 12 are spaced apart from each other, so that four portions 30A-D of the sensor sheet 18 are exposed between the quadrants 16A-D. The portions 30A-D of the sensor sheet 18 form hinges between the quadrants 16A-D of the platform 12.

Referring in particular to Figure 6, in each quadrant 16A-D, the sensor sheet 18 is provided with four load sensors 32 in a two-by-two array, and all sixteen load sensors 32 are electrically connected in parallel by copper tracks 34 laminated into the sensor sheet 18, and the tracks 34 extend to a two-pin connector 36 on the connector portion 19 of the sensor sheet 18.

Each sensor 32 has an electrical conductance that is proportional to the load applied to it. It will therefore he appreciated that the electrical conductance between the pins of the connector 36 will be proportional to the total load applied to all sixteen sensors 32. A known thin film sensor device (manufactured by Tekscan mc, MA 02127, USA under the mark Flexiforce and described in patent document W099/42798A) has a sensor that is connected to a connector by a flexible plastics strip into which a couple of copper tracks are laminated. The sensor sheet 18 of the embodiment of the invention is a development of this known technology using the sheet 18 (rather than a strip) and employing sixteen sensors 32 (rather than a single sensor) connected in parallel.

Referring in particular to Figures 1 and 5, the display unit 14 comprises a rectangular housing 38 that is mounted on the extended portion 26 of the base plate 22A. The top wall 40 of the housing 38 has an opening behind which is mounted a multi-digit 7-segment or graphical display device 42 employing LCD, LED or similar technology. Also inside the housing 38, a programmed microcontroller 44 is connected to the connector 36 on the sensor sheet 18 and drives the display device 42. The microcontroller 44 and display device 42 are powered by a battery 46. One or more push button switches 48 are provided on the front wall of the housing 38 for providing user input to the microcontroller 44. The switch(es) 48 may be arranged so that they can be operated by the user's toe.

Referring now to Figure 8, the sensor sheet 18 is glued to the base plates 22A-D.

Spacer discs 50 are bonded to the undersides of the top plates 24A-D above each sensor 32, and each spacer disc 50 rests on its respective sensor 32. At the four corners of each quadrant 16A- I) the ton nlte 7.4A-D is r.nnnertel to th& hise nlte 72A-D hv nip nroiectjn unwardlv - -r a- - - -r r from the base plate 22A-D and having a head 54 that is a loose snap-fit in a counter-bored hole 56 in the top plate 24A-D. The pins 52: prevent the top plates 24A-D and base plates 22A-D falling apart; do not provide any significant resistance to relative vertical movement of the top plates 24A-D and base plates 22A-D that is encountered during use; and do not project upwardly above the level of the upper surfaces of the top plates 24A-D. It will therefore be appreciated that the weight of each top plate 24A-D, its spacers discs 50 and any load on that top plate 24A-D will be borne entirely by the respective sensors 32, and therefore that the conductance between the pins of the connector 36 will be proportional to the total weight of the top plates 24A-D, spacers discs 50 and any load on the top plates 24A-D.

The microcontroller 44 serves to sense the conductance between the pins of the connector 36, to calibrate the sensed conductance to produce a signal proportional to the load, if any, on the top plates 24A-D, and to scale the calibrated signal to produce an output signal indicative of the load, if any, on the top plates 24A-D in a desired system of units to a desired resolution, such as: Newtons to a resolution of 2 N; kilograms to a resolution of kg; pounds to a resolution of /2 Ib; or stones and pounds to a resolution of " lb. The display device 42 then displays the load indicated by the output signal in that system of units. The microcontroller 33, display device 42 and switch(es) 48 may have ancillary functions and features such as: switching on, switching off and/or auto-switching-off after a predetermined time; back-lighting of the display device 42; selection of the system of units in which the load is displayed; auto- calibration whereby the displayed reading is set to zero when the scales are switched on, on the assumption that there will be no load on the platform 12 at that time; a real-time clock; display of the date and/or time; storage of readings and the dates/times when they were made; textual display of stored readings and times/dates, graphical display of stored readings against time; user log-on so that readings can be attributed to different people (for example members of the same family) and displayed accordingly; and voice synthesis rather than or in addition to visual display of readings.

Referring back to Figure 1, the scales 10 are shown in their opened-out configuration, and the platform 12 is sized such that a person can stand with their left foot on the top plates 24A,D, with their right foot on the top plates 24B,C, with their feet slightly apart, and without their feet overhanging the sides of the platform 12 to any significant extent or touching the housing 38. Typically, the platform 12 may have a width W of about 340 mm and a length L of about 248 mm, and each top plate may have a width and length of 160 mm and 120 mm, respectively, such that width of the hinge portions 30A,C is about 20 mm and the width of the hinge portions 30B,D is about 8 mm.

For storage or transportation, the scales 10 can be folded-up to the configuration shown in Figure 3. In order to do this, first the platform quadrants 16C,D are folded on top of the quadrants 16B,A by hinging about the hinge portions 30B,D, to the configuration shown in Figure 2. Theii, the platform quadrants 16B,C are folded on top of the quadrants 16A,D by hinging about the hinge portions 30A,C, to the configuration shown in Figure 3, such that the hinge portion 30C becomes folded back on itself twice behind the hinge portion 30A, as shown in Figure 4. The quadrants 16A-D therefore form a stack 58 next to, and of approximately the same height as, the display unit 14 Typically, the stack 58 and display unit may have a height H of about 24 mm. Therefore, in its folded-up configuration, the scales 10 may have a size of about 160 mm x 120 mm x 24 mm (in other words about the same size of a typical paperback novel) such that they can readily be carried in a jacket pocket, handbag or larger item of luggage. The scales may be provided with a pouch into which they can be slipped, when folded up, to keep the scales in the folded-up configuration and to protect them. Of course, when the scales are once more required, they can he slipped out of the pouch, opened out to the configuration of Figure 2, and then fully opened out to the configuration of Figure 1.

The top plates 24A-D may deform under load, and if the top plates 24A-D deform to such an extent that their undersides touch the sensor sheet 18, not all of the load will be borne by the sensors 32 so that an inaccurate reading will be obtained. In the embodiment described above, the spacer discs 50 prevent the undersides of the top plates 24A-D touching the sensor sheet 18 under all expected loads. In a modification, as shown in Figure 9, the separate spacer discs 50 are omitted, but instead the top plates 24A-D have thickened portions 60 in the regions of the sensors 32. In a further modification shown in Figure 10, the separate spacer discs 50 are omitted, but instead the sensors 32 are substantially thicker than the sensor sheet 18.

In the embodiment of the invention described above, the pins 52 hold the top plates 24A-D to their base plates 22A-D. In a modification shown in Figure 9, the top plates 24A-D are held to their base plates 22A-D by blocks 62 of highly compressible foam rubber bonded between the top plates 24A-D and base plates 22A-D at their corners. In a further modification shown in Figure 10, the top plates 24A-D are held to their base plates 22A-D by straps 64 of highly flexible material bonded between the top plates 24A-D and base plates 22A-D at their corners. In yet another modification, the upper faces of the sensors 32 are bonded to the spacer discs 50 or the undersides of the top plates 24A-D, and the lower faces of the sensors 32 are bonded to the upper sides of the base plates 22A-D.

In the embodiment of the invention described above, the sensor sheet 18 provides four hinge portions 30A-D between all of the adjacent pairs of platform quadrants 16A-D. As a result, the hinge portion 30A needs to be of sufficient width to reach from the bottom quadrant to the top quadrant in the stack 58 when the scales are in the folded configuration (see Figure 4). Also, the hinge portion 30C needs to be of the same width as the hinge portion 30A, and so the hinge portion 30C become tightly folded back on itself twice when the scales 10 are in the fully-folded configuration (see Figure 4). In a modification to the sensor sheet 18, as shown in Figure 7, the hole 28 in the centre of the sensor sheet 18 is extended to form an open-ended slot 62 in place of the hinge portion 30A, and the width of the hinge portion 30C is smaller, about the same width as the other hinge portions 30B,D. The modified scales are folded-up in a similar fashion to that described above, resulting in a stack with: quadrant 16A at the bottom of the stack; quadrant 16D resting on quadrant l6A and joined thereto by hinge portion 30D; quadrant 1 6C resting on quadrant I 6D and joined thereto by hinge portion 30C; and quadrant 16B resting on quadrant 16C and joined thereto by hinge portion 30B.

Figures 11 to 13 show a second embodiment of scales 10 that is similar to the first embodiment described above, except that the platform 12 is divided into six portions 16A-F arranged in a two-by-three array, rather than four quadrants 16A-D in a two-by-two array. The sensor sheet 18 (Figure 13) provides five hinge portions 30A-E, namely: hinge portion 30A between platform portions 16B,C; hinge portion 30B between platform portions 16C,D; hinge portion 30C between platform portions 16E,F; hinge portion 30D between platform portions 16A,F; and hinge portion 30E between platform portions 16B,E. Furthermore, the sensor sheet 18 is formed with two slots 62A,B, namely: slot 62A between platform portions l6A,B; and slot 62B between platform portions 16D,E. The scales 10 can be moved from the opened-up configuration of Figure 12 to the folded-up configuration of Figure 11 by: folding about the hinge portions 30B,E,D to form three stacks l6A,F, 16B,E and 16C,D; then folding about the hinge portion 30C to form two stacks 16A,F,E,B and 16D,C; and then folding about the hinge portion 30A to form a single stack 58 of the platform portions 16A,F,E,B,C,D, as shown in Figure 11.

It should be noted that the embodiments of the invention and the modifications thereto have been described above purely by way of example and that many other modifications and developments may be made thereto within the scope of the present invention.

Claims

1. Scales for weighing a person, the scales comprising at least four platform portions that are hinged one to another for folding in two directions between an opened-up configuration in which the platform portions are arranged in a two-dimensional array to form a platform on which the person can stand and a folded-up configuration in which the platform portions are arranged in a stack, each platform portion having means for sensing the load applied to that portion when the portions are in the opened-up configuration, and the scales further including means responsive to the sensing means for determining and indicating to the person the total load applied to the platform.

2. Scales as claimed in claim 1, wherein, in the folded-up configuration, the platform portions are arranged in a single stack.

3. Scales as claimed in claim 1 or 2, wherein there are four platform portions that are arranged in a two-by-two array when in the opened-up configuration.

4. Scales as claimed in any preceding claim, wherein the width of the platform is between about 280 mm and about 350 mm when in the opened-up configuration.

5. Scales as claimed in any preceding claim, wherein the length of the platform is between about 240 mm and about 280 mm when in the opened-up configuration.

6 Scales as claimed in any precedmng claim, wherein each platform portion is no more than about 10 mm thick, more preferably no more than about 8 mm thick, and even more preferably no more than about 6 mm thick.

7 Scales as claimed in any preceding claim, wherein the total load indicating means is provided in a housing that is disposed to one side of one of the platform portions when the scales are in the opened-up configuration, and that is disposed alongside the stack when the scales are in the folded-up configuration.

8. Scales as claimed in claim 7, wherein the height of the housing is not substantially greater that the height of the stack when the scales are in the folded-up configuration.

9. Scales as claimed in any preceding claim, wherein each platform portion comprises a base plate and a top plate, the platform portions being hinged together by a flexible sheet that is sandwiched between each base plate and its respective top plate.

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10 - 10. Scales as claimed in claim 9, wherein the means for sensing the load applied to each platform portion comprise a group of electrical load sensors that are fixed to the flexible sheet and in use support the respective top plate above the respective base plate and electrical connections that are mounted on or in the flexible sheet and interconnect the load sensors.

11 Scales as claimed in claim 10, wherein electrical connections are mounted on or in the flexible sheet to connect the groups of sensors to the means for determining and indicating the total load.

12. Scales as claimed in claim 10 or 11, wherein each sensor has an electrical conductance that is proportional to the load applied to that sensor, all of the sensors are electrically connected in parallel, and the means for determining and indicating the total load is operable to determine the resultant conductance of the parallel sensor circuit.

13. Scales as claimed in claim 10 or 11, wherein each sensor has an electrical resistance that is proportional to the load applied to that sensor, all of the sensors are electrically connected in series, and the means for determining and indicating the total load is operable to determine the resultant resistance of the series sensor circuit.

14. Scales for weighing a person, substantially as described with reference to the drawings.