WO2003032612A2

WO2003032612A2 - Fluid pressure hinge mechanism for a foldable electronic device

Info

Publication number: WO2003032612A2
Application number: PCT/EP2002/011066
Authority: WO
Inventors: Maurizio Volpe
Original assignee: Motorola Inc
Current assignee: Motorola Solutions Inc
Priority date: 2001-10-09
Filing date: 2002-09-30
Publication date: 2003-04-17
Anticipated expiration: 2004-04-09
Also published as: GB0124150D0; AU2002333893A1; GB2380765B; GB2380765A; WO2003032612A3

Abstract

The invention relates to a housing, in particular a housing for an electronic device such as radiotelephone. Specifically, the present invention provides a new actuating mechanism for such a housing. At least two fluid reservoirs (152, 160) interconnected by a valve (182) are provided. The fluid reservoirs (152, 160) are preferably filled with a gel such that under pressure applied to the reservoirs (152, 160) the gel moves between the fluid reservoirs (152, 160), causing relative motion between housing portions (110, 120) of the housing 100.

Description

HOUSING FOR AN ELECTRONIC DEVICE

The present invention relates to a housing for an electronic device, in particular a housing for a radiotelephone. Specifically, the present invention provides a new actuating mechanism for such a housing.

Currently there are a wide variety of different form factors and housing arrangements utilized for electronic devices such as radiotelephones, personal digital assistants and pagers. In a common arrangement two housing portions are provided, which can move relative to each other between an open position and a closed position.

One example of this type of arrangement is the "flip" or clam form factor in which the two housing portions are joined by a hinge along one edge. In the closed position at least a part of each of the housing portions is adjacent the other housing portion and the housing portions may be swung away from each other about the hinge to an open position.

In another example of this type of arrangement the two housing portions are joined by a sliding cam mechanism and one of the housing portions may be moved along and substantially parallel to the other housing portion between the open and the closed positions.

The provision of relatively movable housing portions in an electronic device is desirable as the overall size of the device when closed is minimized while providing a larger surface area for display/keypad for the device when open. However, the use of a hinge or cam in the actuating mechanism increases the complexity of the design and the cost of manufacture and the malfunction of these parts can reduce the life of the electronic device. The present invention seeks to alleviate at least some of the disadvantages of the prior art arrangements.

In accordance with the invention, there is provided a housing for an electronic device, the housing having a first housing portion and a second housing portion and having a first fluid reservoir and a second fluid reservoir, the first fluid reservoir being in fluid connection via a valve with the second fluid reservoir arranged such that applying pressure to the first fluid reservoir causes relative motion of the two housing portions.

The use of the fluid filled reservoirs in fluid connection via a valve dispenses with the need for a mechanical actuating mechanism using hinges and cams. The valve is pressure-sensitive, and allows fluid to flow in response to the pressure imbalance between a first side and a second side exceeding a threshold.

In one arrangement of the invention, applying pressure directly to one of said first or second fluid reservoirs causes fluid flow therefrom to the other of said first or second fluid reservoir through the valve. In a further arrangement of the invention, applying pressure to at least one housing portion causes fluid to flow from one of said first or second fluid reservoirs to the other of said first or second fluid reservoir through the valve.

Advantageously the first fluid reservoir comprises two partial fluid reservoirs, each of which is preferably in fluid connection with the second reservoir via a respective valve. Most advantageously the two partial reservoirs are arranged on opposing sides of one of the housing portions. This arrangement is particularly advantageous used in a small hand-held device such as a radiotelephone.

Advantageously one of the fluid reservoirs forms a hinge portion between first and second housings. Preferably, the valve is formed from a flexible sheet. This arrangement is simple and robust. Alternatively, the valve may be implemented as a necked pipe or ball valve, for example.

For a better understanding of the present invention, and to show how it may be brought into effect, reference will now be made, by way of example, to the accompanying drawings, in which:

Figure 1a) shows a side view of an exemplary housing in accordance with an embodiment of the invention in a closed position;

Figure 1 b) shows a plan view of an exemplary housing in accordance with an embodiment of the invention in a closed position;

Figure 1c) shows a side view of an exemplary housing in accordance with an embodiment of the invention in an open position;

Figure 1d) shows a plan view of an exemplary housing in accordance with an embodiment of the invention in a open position;

Figures 2a) - 2d) illustrate the operation of one embodiment of a valve in the exemplary housing shown in Figures 1a)-1d).

Figure 3a)- 3d) illustrate the operation of a further embodiment of a valve in the exemplary housing shown in Figures 1a)-1d)

Figure 4 illustrates the operation of a further embodiment of a valve in the exemplary housing shown in Figures 1a)-1d)

The present invention will now be described with reference to a clam form factor radiotelephone as an exemplary embodiment of the use of the housing of the invention in an electronic device. However, it will be clear to a skilled person that the present invention can be applied to other electronic devices requiring relative motion between a first housing portion and a second housing portion of the housing.

Figures 1a)-1d) show an exemplary housing for a clam form factor radiotelephone 100. The housing for the clam form factor radiotelephone 100 has a first housing portion 110 and a second housing portion 120. As shown in Figure 1d), the first housing portion 110 carries a keypad area 130 and the second housing portion carries a display 140, although it will be clear to a skilled person that this is not essential to the invention.

A first fluid reservoir, comprising the two partial fluid reservoirs 151 152, is provided in the first housing 100. A second fluid reservoir 160 is also provided, and forms a hinge portion between the first housing portion 110 and the second housing portion 120. The two partial fluid reservoirs 151 152 are connected to the second fluid reservoir 160 via respective tubes 171 , 172 having respective valves 181 , 182 disposed therein.

Fluid is contained in a fluid system formed by the first fluid reservoir, comprising the two partial fluid reservoirs 151 , 152, the second fluid reservoir 160 and the tubes 171, 172. As is illustrated by the different shadings and shapes of the two partial fluid reservoirs 151, 152 and the second fluid reservoir 160 in Figures 1a)- 1d), most or all the fluid of the fluid system is contained in the partial fluid reservoirs 151 and 152 in Figures 1a) and 1b) whereas most or all of the fluid of the fluid system is contained in the second fluid reservoir 160 in Figures 1c) and 1d).

The structure of the valves 181, 182 in accordance with an embodiment of the invention will now be described with reference to Figures 2a)-2b).

In Figures 2a)-2d) side X of the valves 181 , 182 represents the first fluid reservoir (or partial fluid reservoir 151 , 152) side and Y represents the second fluid reservoir 160 side. The pressure at the first fluid reservoir (or partial fluid reservoir 151 , 152) side is represented by Pi and the pressure at the second fluid reservoir 160 side is represented by P₂. As mentioned above, the valves 181 , 182 are disposed within the respective tubes 171, 172. Each of the valves 181 , 182 in the illustrated exemplary embodiment of the invention has a flexible sheet portion 183 and an attachment portion 184 to attach the flexible sheet portion 183 to the respective tube 171, 172.

As can be seen from Figures 2a)-2d) the flexible sheet portion 183 is larger than, or has a larger diameter than the inner cross-section of the tube 171 , 172. As a result, as shown in Figures 2b) and 2c), the flexible sheet portion 183 is able to block the tube 171 , 172 and prevent fluid communication up to a moderate imbalance of pressure between pressure Pi and pressure P₂. However, since flexible sheet portion 183 is flexible, under a greater imbalance of pressure between pressure P-i and pressure P₂, the flexible sheet portion gives way and allows fluid communication between the fluid reservoirs, as shown in Figures 2a) and 2d).

The operation of the illustrated embodiment of the invention will now be described with reference to Figures 1a)-1d) and 2a)-2d).

When the clam form factor radiotelephone 100 is in the closed position, as shown in Figures 1a) and 1b), partial fluid reservoirs 151 , 152 hold most or all of the fluid and the second fluid reservoir 160 holds very little or none of the fluid and so pressure P₁ is greater than pressure P₂. However, the flexible sheet portions 183 of the valves 181 , 182 are designed to be able to withstand this level of pressure imbalance between pressure Pi and pressure P₂ and so flexible sheet portions 183 of the valves 181 , 182 block the respective tubes 171 , 172 and prevent fluid communication between the partial fluid reservoirs 151 , 152 and second fluid reservoir 160. When the user wishes to open the radiotelephone to make a call, for example, the user presses in direction A shown in Figure 1b). The pressure Pi in the partial fluid reservoirs 151 , 152 rises as a result until the pressure imbalance between pressure Pi and pressure P₂ rises sufficiently that the flexible sheet portion 183 gives way and allows fluid communication between the fluid reservoirs. Fluid can then flow from the respective partial fluid reservoir 151 152 through the respective valve 181 , 182 into the second fluid reservoir 160. This causes the second housing portion 120 to move away from the first housing portion 110 and open the radiotelephone 100, as shown in Figures 1c) and 1d).

Once the clam form factor radiotelephone 100 is in the open position, as shown in Figures 1c) and 1d), the user releases the pressure A and the flow of fluid ceases, allowing the flexible sheet portion 183 to block the tube 171, 172 as shown in Figure 2b).

In this situation, second fluid reservoir 160 holds most or all of the fluid and the partial fluid reservoirs 151 , 152 hold very little or none of the fluid. The pressures stabilize at a moderate imbalance between pressure P₁ and pressure P₂ with pressure P₂ being greater than pressure Pi. The flexible sheet portions 183 of the valves 181 , 182 are designed to be able to withstand this level of pressure imbalance between pressure Pi and pressure P₂ and so flexible sheet portions 183 of the valves 181, 182 block the respective tubes 171 , 172 and prevent further fluid communication between the partial fluid reservoirs 151 , 152 and second fluid reservoir 160, as shown in Figure 2c).

When the user wishes to close the radiotelephone, the user presses the second housing portion 120 of the radiotelephone 100 in direction B shown in Figure 1c). The pressure Pi in the second fluid reservoir 160, and therefore the pressure imbalance between pressure P₂ and pressure P-i, rises as a result. Eventually, the pressure imbalance between pressure P₂ and pressure Pi rises sufficiently that the flexible sheet portion 183 gives way and allows fluid communication between the fluid reservoirs. Fluid can then flow from the second fluid reservoir 160 through the respective valve 181, 182 into the respective partial fluid reservoir 151 152 as shown in Figure 2d). This allows the second housing portion 120 to move towards the first housing portion 110 and close the radiotelephone 100 as shown in Figures 1a) and 1b).

Once the clam form factor radiotelephone 100 is in the closed position again, as shown in Figures 1a) and 1b), the flow of fluid ceases, allowing the flexible sheet portion 183 to block the tube 171 , 172 once more.

The valve has been described as comprising a flexible sheet. In a preferred embodiment the flexible plate is made from elastomeric thermoplastics or silicone having an appropriate flexural modulus.

In an exemplary embodiment of the invention for a clam form factor radiotelephone having a volume around 70cc, typical values are a flexible sheet portion having length 2mm, thickness 0.2mm and flexural modulus 80 N/mm² being disposed in a tube with cross-section 2mm² and width 1mm with area interference 40%. A squeeze force of 8N on a squeeze area of 2cm² will produce a pressure of 40kPa resulting in an inertial moment of 0.001333mm⁴ and a deflection of 0.75mm.

Further embodiments of valves which may be used in the invention are shown in Figures 3a)-d) and Figure 4.

Figures 3a)-d) illustrate a necked tube that can be used as a valve in accordance with an embodiment of the invention. As shown most clearly in Figures 3a) and 3b) the tube 171, 172 has a necked portion 185 acting as a valve. When the pressure differential between pressures Pi and P₂ on each side of the necked portion is below a threshold, the necked portion 185 remains closed as shown in Figures 3a) and 3b). When the pressure differential between pressures Pi and P₂ on each side of the necked portion increases above the threshold, the pipe is deformed and the necked portion 185 opens to allow fluid to flow, as shown in Figure 3c) and 3d).

Figure 4 illustrates a ball valve having a ball 186 and a spring 187 disposed in the tube 171 , 172. When the pressure differential between pressures Pi and P₂ on each side of the ball valve is below a threshold, the ball 185 is held in place by the spring 187 to block the tube 171 , 172, as shown in Figure 4. When the pressure differential between pressures Pi and P₂ on each side of the valve increases above the threshold, the ball 186 is displaced compressing the spring 187 allowing fluid to flow through the tube 171 , 172.

Although the described embodiment of the invention has two partial fluid reservoirs as the first fluid reservoir and a single second fluid reservoir, it will be appreciated that other arrangements, such as a single first fluid reservoir and a plurality of second fluid reservoirs are also possible in accordance with the invention.

Preferably in the described embodiment the first reservoir (comprising the two partial fluid reservoirs) is of larger volume than the second fluid reservoir. In this way when the clam form factor radiotelephone 100 is in the closed position the second fluid reservoir is completely empty to minimize the bulk of the hinge portion. A slight amount of fluid will remain on the second fluid reservoir side of the tubes 171 , 172 to provide the necessary pressure P₂ to keep the valve 181, 182 closed.

Moreover, the invention is not limited to the described situation in which a first relative motion between the housing portions is caused by direct pressure on a first fluid reservoir and a second relative motion between the housing portions is caused by indirect pressure on the second reservoir arising from pressure exerted on a housing portion, and any combination of direct or indirect pressure may be used.

In addition, a skilled person will appreciate that the first and second fluid reservoirs may be arranged and shaped in a number of different ways in order to effect relative motion between two housing portions. In particular, the invention is not limited to a clam form factor. The fluid reservoirs should be shaped so as to produce appropriate forces on the housing portions to cause relative motion therebetween, as will be apparent to a skilled person.

Although the invention has been desαibed using a bi-directional valve in the tube linking the first and second fluid reservoirs, it would also be possible to implement the invention using a first tube and a second tube linking the fluid reservoirs, each of the first and second tubes having a valve disposed therein or by using a strictly uni-directional non-return valve together with a bypass.

The fluid used in the present invention may be any fluid capable of functioning as described to cause relative motion between the housing portions. The fluid is preferably a liquid or a gel, since these substances are substantially incompressible. The force that has to be applied in order to open the valve clearly depends partly on the viscosity of the fluid, and so the viscosity of the fluid will be determined accordingly. However, a gas could be used with an appropriate design of reservoirs and valves.

In a particularly advantageous arrangement of the invention, the reservoirs are formed as an integral part of the housing. In this way at least part of the housing performs the function of a reservoir. This is particularly advantageous in respect of the second fluid reservoir 160, where the pressure difference results in deformation of the housing, leading to the relative movement of the housing portions. Since the reservoir forms part of the housing, there is more space within the housing for electronic circuitry: specifically, no mechanical hinge is necessary.

As will be apparent from the above description, the present invention provides a housing, in particular for an electronic device, having a robust actuating mechanism.

As will be apparent to a skilled person, the invention could be implemented in a different form from that shown herein, and so the invention is intended to encompass all arrangements and variations within the scope of the appended claims.

Claims

1. A housing for an electronic device, the housing having a first housing portion and a second housing portion and having a first fluid reservoir and a second fluid reservoir, the first fluid reservoir being in fluid connection via a valve with the second fluid reservoir arranged such that applying pressure to the first fluid reservoir causes relative motion of the two housing portions.

2. The housing as claimed in claim 1 wherein applying pressure directly to one of said first or second fluid reservoirs causes fluid flow therefrom to the other said first or second fluid reservoir through the valve.

3. The housing as claimed claim 1 or 2 wherein applying pressure to at least one housing portion causes fluid to flow from one of said first or second fluid reservoirs to the other of said first or second fluid reservoir through the valve.

4. The housing as claimed in any preceding claim wherein the first fluid reservoir comprises two partial fluid reservoirs.

5. The housing as claimed in claim 4 wherein the two partial fluid reservoirs are each in fluid connection with the second fluid reservoir via a respective valve.

6. The housing as claimed in claim 4 or 5, wherein the two partial reservoirs are arranged on opposing sides of one of the housing portions.

7. The housing as claimed in any preceding claim wherein one of said first or second fluid reservoirs forms a hinge portion between the first and second housing portions.

8. The housing as claimed in any preceding claim wherein the or each valve is disposed in a tube connecting the respective fluid reservoirs.

9. The housing as claimed in any preceding claim wherein the or at least one valve comprises a flexible plate.

10 The housing as claimed in one of claims 1-8 wherein the or at least one valve is formed by a necking in the respective tube.

11. The housing as claimed in one of claims 1-8 wherein the or at least one valve comprises a ball valve.

12. A radiotelephone having a housing as claimed in any preceding claim.