The present invention relates to a device or device holder comprising a flexible substrate having a flat and a curled state, for removably attaching the device or device holder to an object, wherein the device or device holder has at least one surface comprising a recess, said surface facing said flexible substrate, and wherein said flexible substrate is movably affixed to said surface and extends beyond said surface as well as a kit-of-parts comprising said device or device holder and a method for removably attaching said device or device holder to an appendage or the torso of the user of the device or device holder.

Related Art

There is an ever-increasing number of devices, in particular electronic devices that provide utility to a user by, e.g. measuring a body function, allowing communication, providing music, providing energy to other devices etc., which are small enough to be carried around by the user during the use of the device. In this context the phrase "wearable devices" or more specifically "wearable computer" have been coined to refer to devices that are removably attached to a part of the body of the user thus freeing the users hands for other uses. Devices of this type have been attached by clips that are either part of the device itself or part of a device that is adapted to hold the device to be worn, i.e. in the latter case the device is removably attached to or inserted into the device holder, which is in turn removably attached to the body of the user. Other known means for attaching devices include hook and loop fastening straps, like e.g. Velcro ^® and elastic bands. Wearable devices have also been designed to be an integral part of the clothes of the user, e.g. integrated into a jacket or pants.

US 2013/044215 describes the use of bi-stable springs to removably attach computers and watches to a users appendage. A bi-stable spring is a spring that has two equilibrium positions. This property allows the spring to assume two distinct configurations in each of which it will remain until a certain force is exerted that overcomes the retaining force that keeps the spring in one of the equilibrium states. For example, bi-stable springs can be flat in a first equilibrium position and can be curled in a second equilibrium position. This property has been used in devices such as the slap -bracelet, also called the slap wrap. The slap bracelet consists of layered flexible steel bands, typically sealed within a fabric cover. For the slap bracelet the second equilibrium position is typically reached by slapping the flat side of the bi-stable spring across the wrist in a way that is forceful enough to overcome the retaining force of the bi-stable spring keeping it in the first equilibrium position, at which point the bracelet curls around the wrist and stays relatively secure in a roughly circular position around the wrist.

The forceful slapping movement required to attach the slap-bracelet to the wrist has several disadvantages, which comprise inter alia that the slap bracelet may not be optimally positioned on the wrist due to the movement required to create sufficient force to overcome the retaining force which keeps the bi-stable spring in its flat equilibrium state and that the attaching process may cause discomfort to users. Therefore, there is a need to provide a device or a device holder that provides at least one of the following advantage: easy one handed attachment, attachment without slapping movement, attachment without discomfort, improved positioning of the device or device holder during the attachment process.

Summary of the Invention

The need is satisfied by the subject-matter of the independent claims. The dependent claims specify particular embodiments of the present invention.

According to an embodiment of the present invention a device or device holder is provided comprising a flexible substrate having a flat and a curled state, for removably attaching the device or device holder to an object, wherein the device or device holder has at least one surface comprising, essentially consisting of, consisting of a recess, said surface facing said flexible substrate, and wherein said flexible substrate is movably affixed to said surface and extends beyond said surface. The arrangement of the flexible substrate in a way that it faces the surface comprising, essentially consisting or consisting of the recess provides that during attachment to the object the flexible substrate is forced into the recess once the device is moved towards the object.

If, for example the recess is a cut-out in the form of a cylinder segment that conforms in radius approximately to the radius of the arm of a user, the device is attached to the arm by applying the device with the flexible substrate in its flat state and in a way that a part of the flexible substrate is the first to contact the arm of the user. If the device is now moved further towards the arm of the user the part of the flexible substrate facing the surface comprising, essentially consisting or consisting of the recess is moved into the recess and thereby forced out of its flat state up to the point, in which the retention force of the flexible substrate is overcome and the flexible substrate as a whole changes into its curled state.

As is evident from above example the attaching of the device or device holder (with or without installed device) can be carried out with one hand only and without actually touching the flexible substrate, i.e. it is sufficient to hold the device or device holder in the correct orientation - i.e. flexible substrate in its flat state and recess of the surface facing the object - and to move the device or device holder towards the desired attachment position on the object, whereby a part of the flexible substrate is moved into the recess and thereby converting the flexible substrate from its flat to its curled state.

The size and type of the device is not particularly limited. It is typically sized to be attached to an arm, wrist or leg of a user without impeding the movement of the user. If the device is designed to be attached to the torso of the user, it may be larger and/or heavier without interfering with the movement of the user. The weight of the device will influence the choice of the flexible substrate, which has to be selected in such that it provides a secure attachment of the device to the user once it assumes its curled state. Typically, devices of the present invention have a weight in the range of 50 g to 1.000 g, if attached to the wrist, arm or leg of a user. If attached to the torso of the user, they may have a higher weight, typically in the range of 200 to 3.000 g. Preferred devices of the invention are selected from the group consisting of a battery, a monitoring device, a display, a micro-computer, a mobile phone, a tool, a tool box, a watch, a music player, a liquid container, fixing pin cushion, a flotation device and a lamp.

Ideally, the device to be attached is already configured with a surface comprising, essentially consisting or consisting of a recess and a flexible substrate positioned as outlined above. In this case the device itself can be attached directly to the user. However, there are many devices on the market that are not originally configured with a surface comprising essentially consisting or consisting of a recess and a flexible substrate. Such devices may nevertheless take advantage of the attachment system outlined above by configuring a device holder with a surface comprising, essentially consisting or consisting of a recess a recess and a flexible substrate positioned as outlined above and wherein the device holder is configured to hold the respective device.

Preferred devices that may be attached by means of a device holder are selected from the group consisting of a battery, a monitoring device, a display, a micro -computer, a mobile phone, a tool, a tool box, a liquid container, a watch, a map, a music player, and a lamp. The device holder is preferably configured to securely hold the device. This may be achieved by various art known means including hook and loop fastening straps, which are attached both on the device to be held and the device holder, respectively. Depending on the device to be held the device holder may also be configured to have two opposing groves into which the device can be slid. In this case, the device may be held in the device holder by springs that are positioned within one of the groves or by spring-mounted ledges or levers that hold the device once fully inserted into the device holder.

In a preferred embodiment the monitoring device is monitoring at least one physiological state of an object, preferably of a user. Preferred physiological states to be monitored comprise heart rate, oxygen saturation, conductivity and/or temperature, preferably of the skin of a user; location and/or movement of the object, preferably of the user.

In a preferred embodiment the flexible substrate is a bi-stable spring substrate. Bi-stable springs and their components are well known in the art. The selection of the metals forming the bistable spring allows determining the force required to overcome the retaining force, i.e. the force for converting the bistable- spring from one equilibrium state to another equilibrium state. The force required to overcome the retaining force is also determined by the width and the thickness of the bistable spring. Thus, it is preferred that the width, the thickness and the material of the bistable-spring are selected in such that the application of a force of less than 20 N, preferably of less than 15 N, more preferably of less IO N and most preferably of less than 5 N to the device or device holder will force the bistable spring to change from its flat state to its curled state when in contact with the object. The force required will in part also depend on the width of the recess in the surface into which the bistable spring will be forced once pressure is applied to the device to move it into the direction of the object. The wider the width of the recess the smaller the force.

Preferably, the cross-section of the flexible substrate is rectangular.

It is also possible to layer two or more bistable-springs on top of each other, if it is desired to provide strong holding forces, e.g. if the object is heavy and/or if the device is used during sport and may experience strong accelerating forces. In a typical embodiment for attaching the device or device holder to the arm of a user, the bistable- spring will have a width between 2 to 4 cm, more preferably about 3 cm.

In a preferred embodiment the flexible substrate, preferably the bi-stable spring is covered by textile material or an elastic material, e.g. rubber or maybe rubberized under the textile material to improve the wearing properties, e.g. reduce sweating, increase the skin comfort and/or the feeling of coldness when attached. The surface of the textile cover or elastic material, rubber may also increase the friction between the object and the attached device or device holder and thereby decrease the slip of the device or device holder during use. The cover of, e.g. the flexible substrate may also be colored as may be required by the particular use or to match or contrast the color of the device.

In a preferred embodiment the flexible substrate is configured to conform in its curled state to the shape of the object. Preferably the object is a rounded object, more preferably a human or non-human animal appendage or torso. Examples for such objects are wrist, finger, upper arm, lower arm, thigh or shank, in particular of a human user.

The recess in the surface is preferably configured in size and orientation in such that the flexible substrate can be forced into the recess, once the device or device holder is moved towards the object in a way that part of the flexible substrate touches the object and is then forced into the recess upon further movement of the device or device holder towards the object.

Preferably, the recess has a concave cross-section, is a cut-out from said surface with the shape of a cylinder segment, a cut-out from said surface with the shape of a triangular or hexagonal prism, or is a cut-out from said surface with the shape of cube or cuboid. It is preferred the recess is a cut-out from said surface with roughly the shape of a section of the object to which it is to be attached. Thus, if the object is the arm of a user the recess has preferably the form of a cut-out in the shape of a cylinder segment. This allows the arm to snuggly fit into the recess to provide maximum contact between the object and the device or device holder once the flexible substrate has changed into its curled position. Based on the information provided herein the skilled person can design a recess of a suitable width, length, depth and shape in the surface of the device or device holder based on the respective object to which the device or device holder is to be attached. It is important that the depth of the recess is selected for a given flexible substrate in such that at the least when the part of the flexible substrate that can be moved into the recess is fully moved into the recess, e.g. makes contact with the bottom of the recess, that under these circumstances the flexible substrate changes from its flat to its curled state.

The surface with the recess is the surface that will face the object, e.g. the arm of the user once the device or device holder is attached. The recess will typically only cover part of this surface. In a preferred embodiment the recess extends over the entire surface of the device or device holder facing said flexible substrate, i.e. the surface consists or essentially consists of the recess, and which in turn will face the object once attached. In this embodiment the surface is identical to the surface of the recess.

A typical device or device holder for attachment to the upper arm will have a rectangular shape with a width of 4 to 8 cm and a length of 10 to 15 cm. Accordingly, the surface facing the flexible substrate has a rectangular shape with a width of 4 to 8 cm and a length of 10 to 15 cm. In this embodiment it is preferred that the surface consists of the recess, i.e. that the entire surface facing the flexible substrate has the form of a recess. For such devices or device holders it is preferred that the recess is a cut-out with the shape of a cylinder segment.

For a typical width of the recess of between 4 to 10 cm the depth of the recess is between 2 to 6 mm in particular if the recess is a cut-out of the shape of a cylinder segment.

The surface comprising the recess may be flat or curved outside the recess. It is, however, preferred that the surface comprising the recess is configured outside the recess not to interfere with the movement of the device towards the object and of the flexible substrate into the recess, i.e. by contacting the object at a position outside the recess, which may impede further movement of the device or device holder towards the object. Thus, preferably the surface comprising the recess is flat outside the recess.

The flexible substrate is movably affixed to the surface, preferably closed to or at the edges of the recess. It is also possible that the attachment point is within the recess, preferably close to the edge of the recess with the surface. In those embodiments, in which the surface is or is essentially identical with the surface, the attachment point is close to an adjacent surface, e.g. the sides of the device. The provision of a connection between the device or device holder and the flexible substrate that does not impede the movement of the part of the flexible substrate spanning the recess into the recess, facilitates the transition between the flat and the curled state of the flexible substrate. It is preferred that the flexible substrate is movably affixed to the device or device holder by a shackle, a hoop, or a bracket through which the flexible substrate is inserted. These are preferably positioned at the edges of the recess. In a preferred embodiment, the flexible substrate is movably affixed to the device or to the device holder by two shackles, or by two hoops, or by two brackets. It is further preferred that the recess has at least two edges, and that said two shackles or said two hoops or said two brackets are positioned at the edges of the recess, i.e. a first shackle (or hoop or bracket) is positioned at the first edge of the recess, and a second shackle (or hoop or bracket) is positioned at the second edge of the recess.

As indicated above, the flexible substrate is movably affixed to the surface of the device or of the device holder. In preferred embodiments of the present invention, the flexible substrate is movable in relation to the device or the device holder, regardless whether the flexible substrate is in the flat state or in the curled state. This can be achieved, for example, by using two shackles or two hoops or two brackets that are positioned at the edges of the recess, as explained above. These embodiments, in which the flexible substrate is movable in relation to the device or the device holder both in the flat state and in the curled state, are particularly advantageous. For example, when the flexible substrate is movable in relation to the device or the device holder in the flat state, then the device or device holder can be separated from the flexible substrate, so that different methods of cleaning and/or disinfection can be applied to the device or device holder and to the flexible substrate. In addition, it is possible to remove a first device or device holder from the flexible substrate and then to affix a second different device or device holder to the flexible substrate as desired or needed by the user. Moreover, when the flexible substrate is movable in relation to the device or the device holder in the curled state, then the position of the device or device holder can still be changed (in other words: adjusted) when the device or device holder has already been attached to the object. For example, the flexible substrate with the device or device holder can be affixed to the upper arm of a user, whereby the flexible substrate enters the curled state. The fact that the flexible substrate is movable in relation to the device or the device holder while being in the curled state allows the user to adjust the position of the device or the device holder according to the user's preferences. For example, the device or device holder can be moved to the front side of the arm, when the user often needs to touch the device. On the other hand, the device or device holder can be moved to the side of the arm or to the back of the arm, when it is not necessary to touch the device.

The length of the flexible substrate is chosen in such that once it attains its curled state it provides a secure attachment to the object. When such secure attachment can be obtained, depends also on the shape of the object. For objects with an essentially round shape, attachment can be attained, if the flexible substrate has a length of at least 50% of the circumference of the object. More preferably the flexible substrate in its curled state has a length of at least 70% of the circumference of the object, more preferably of at least 80% and more preferably of at least 90%. For a secure attachment, it is not required that the two ends of the flexible substrate overlap in the curled state. For attaching the device or device holder to the upper arm of a subject, the flexible device will typically have a length between 25 and 35 cm. Preferably the device or device holder is positioned essentially in the middle of the flexible substrate, i.e. the length of the flexible substrate protruding from the edges of the surface is essentially identical.

In a preferred embodiment the device is a battery. In this preferred embodiment it is preferred that the device further comprises a control panel for controlling a separate electric device. This is of particular importance in the clinical setting, since many devices that the physician or dentist uses during examination and/or surgical or dental procedures require electric energy like, e.g. lamps attached to surgical loupes. Thus, the separate electric device is preferably a surgical loupe and/or lamp attached to the loupe.

The control panel may react to pressure or changes of capacitivity, i.e. may be configured as a capacitive switch. The control panel may control intensity of a light and may be used to switch a separate electric device on or off.

Since the device or device holder of the present invention can be easily and single handedly attached to a user, e.g. the upper arm of a user, it provides particular advantages in a clinical setting, where the use of two hands to attach the device may compromise sterility. Accordingly, it is also preferred that the device or device holder, in particular the control panel, is configured to be wipe-disinfectable and/or is covered with a layered set of films that are configured to be separately removed.

In a further aspect the present invention provides a kit-of-parts comprising

(i) device or device holder of the invention, wherein the device a battery;

(ii) a separate electric device; and

(iii) a cable connection between the battery holder unit and said separate electric device. In this embodiment it is preferred that the electric device is a surgical loupe.

In a further aspect the present invention provides a method for removably attaching a device or device holder to a user's appendage or torso, comprising the steps:

(a) providing a device or device holder of the invention;

(b) contacting said appendage or torso with the flexible substrate having a flat and a curled state in its flat state; and

(c) moving the device or device holder towards the user's appendage or torso, whereby said flexible substrate is moved into the recess of the surface, thereby overcoming a retaining force of said flexible substrate retaining it in its flat state, and whereby the flexible substrate changes into its curled state and curls around said appendage or torso of the user to attach the device or device holder to said appendage or torso.

Detailed Description of the Invention

In the following the invention will be described in greater detail with reference to the Figures appended hereto.

Fig 1 Panel A shows a side view of a preferred embodiment of the device (1) of the invention in which the surface (20) that faces the flexible substrate (10) essentially consists of the recess (30), i.e. the entire surface has a cut-out in the shape of a cylindrical segment. At each end of the surface object a bracket (40) is positioned through which the flexible substrate is movably affixed to the device (1). The flexible substrate is in its flat state. The arrow indicates the width of the recess (30). Panel B shows a bottom view of the device (1) which shows the surface (20) and the recess (30) which faces the flexible substrate (10). This device is intended for attachment to an essentially round object, i.e. an upper arm.

Fig. 2 Panel A shows the device (1) of the invention with the flexible substrate (10) in its curled state, i.e. after it has been pressed to the object forcefully enough to overcome the resisting force keeping the flexible substrate in its flat state. Panel B show a plan view of the arm of a user and the device attached to the upper arm of said user.

Fig. 3 shows the correlation between the width (W), the radius (R) of a cut-out in the form of a cylinder segment and the depth (d = R-y) of the recess in a preferred embodiment of the device (1) in which the surface (20) that faces the flexible substrate (10) essentially consists of the recess (30), i.e. the entire surface has a cut-out in the shape of a cylindrical segment. In a preferred embodiment the dimensions of (W) and (d) can be determined based on the properties of the respective flexible substrate it is that. W and d should be chosen in such that the force applied when attaching the device or device holder of the invention is sufficient to overcome the force retaining the flexible substrate in its flat state in order to transform it into its curled state. To transform the flexible substrate into its curled state a force (G) has to be applied, preferably to the middle of the flexible substrate (10). The transformation occurs once the flexible substrate is bend by the distance d from its flat position (this is comparable to the bending of a beam with rectangular cross-section, with a width (b) and a thickness (t) and the length (L). Since for the devices and device holders of the present invention the bending occurs between the points at which the flexible substrate is affixed to the surface the length can be equated to the width (W) of the recess. Thus, it is preferred that the recess has at least a depth of d for a given W. The force for bending of the flexible substrate can be approximated by Hook's law as follows:

G = k * d (1) wherein k is the spring constant. The variable k is dependent of the geometry of the flexible substrate (10), i.e. b, t and L, as well as properties of the spring, namely the E-module (E).

As outlined above, it is preferred that the flexible substrate has a rectangular cross section.

In this case k is determined as follows: k = 4Ebt ³ /W ³ (2) For a given flexible substrate force G required to transform the flexible substrate from its flat state to its curled state can be determined experimentally. The depth d can then be determined as follows: d = G/k (3)

Thus, d is the minimum depth required in this preferred embodiment. If the recess is in the form of a cut-out in the shape of a cylindrical segment then it is possible to determine the radius of the cylinder by the following equation:

R = (d ² + (W/2) ² )/ 2d (4)

Thus, this radius (R) of the cut-out, provides a depth d into which the flexible substrate can be moved, which will allow the transformation of the flexible substrate with applying minimal force G.

While this principle of determining d and W is exemplarily shown in Fig. 3 for the type of recess that has a cut-out in the shape of a cylindrical segment, i.e. the radius (R) for the cylinder can be indicated, it is clear that preferred W's and d's of differentially shaped recesses can be determined following the same equation in as long as the recess is shaped in such that the flexible substrate can be moved into the recess up to a depth of at least d. The depth of the recess for a given W may be larger in some embodiments.