WO2009115963A1

WO2009115963A1 - Button assembly comprising an electronic component and a depressable button for operating the component

Info

Publication number: WO2009115963A1
Application number: PCT/IB2009/051044
Authority: WO
Inventors: Arjan Slot; Frans W. Rozeboom; Thelma F. Geusebroek
Original assignee: Koninklijke Philips Electronics N.V.
Priority date: 2008-03-21
Filing date: 2009-03-13
Publication date: 2009-09-24
Also published as: DE202009003843U1; EP2104125A1

Abstract

A button assembly (2) comprises a electronic component (9), a depressable button (3) for allowing a user of the button assembly (2) to operate the electronic component (9), actuating means (13) which are positioned at a back side of the button (3), and which are adapted to follow a displacement of the button (3) and to act upon the electronic component (9), a sealed casing (12) enclosing the electronic component (9), and a resilient member (22) which is incorporated in a wall of the casing (12). The actuating means comprise an actuating element (13) extending through the resilient member (22) without intermediate space, wherein the actuating element (13) is adapted to act upon the electronic component (9) directly. In this way, it is achieved that the electronic component (9) is protected from external influences, even though the actuating element (13) is allowed to extend from the outside of the casing (12) to the inside of the casing (12).

Description

Button assembly comprising an electronic component and a depressable button for operating the component

FIELD OF THE INVENTION

The present invention relates to a button assembly, comprising: an electronic component such as a switching device, i.e. a device which is adapted to be arranged in an electronic circuit and to assume a state for interrupting the circuit or a state for closing the circuit, a depressable button for allowing a user of the button assembly to operate the electronic component, actuating means which are positioned at a back side of the button, and which are adapted to follow a displacement of the button and to act upon the electronic component, a sealed casing enclosing the electronic component, and a resilient member which is incorporated in a wall of the sealed casing. The present invention also relates to an appliance comprising at least one button assembly, to a button unit comprising at least two button assemblies, and to an appliance comprising such a button unit.

BACKGROUND OF THE INVENTION Many appliances comprise one or more buttons which are suitable to be operated by a user of the appliance for providing input to the appliance. In this way, the user has the possibility of controlling the operation of the appliance according to his/her desires. Buttons are often used for operating a switching device, i.e. a well-known device which is adapted to be arranged in an electronic circuit, and which serves for either interrupting or closing the circuit.

Various types of buttons are available, including depressable buttons, i.e. buttons which are arranged such as to be displaced in an inward direction with respect to the appliance under the influence of pressure exerted by the user. In most cases, measures are taken to ensure that a depressable button can only be displaced for a certain extent, and that the button returns to an initial position when the pressure is removed. Furthermore, it is usual for the button to be arranged in a hole in a housing of an appliance, wherein a front side of the button may be flush with a surface of the housing in the initial position, or may be protruding with respect to this surface. In the case of an appliance in which steam and/or a liquid such as water are used and/or emitted during operation, it is important that the electronics of the appliance are protected from the steam and/or the liquid. In particular, it is important that electronics which are located behind a button are covered, as when the appliance is operated such as to emit steam and/or liquid, a small quantity of the steam and/or spilled droplets of the liquid may enter the appliance again through the hole in the housing in which the button is arranged. This problem is all the more urgent in case the buttons are arranged in a portion of the housing surface having a horizontal orientation or close to horizontal orientation. Furthermore, there may be a risk of steam and/or liquid reaching the electronics at the inside of the appliance, so that it is not sufficient to simply seal the button in its hole for eliminating external influences.

In order to ensure safe and reliable functioning of the electronics, and to avoid a situation in which steam and/or a liquid may reach the electronics of an appliance, it is known to apply a button assembly as mentioned in the opening paragraph. In this button assembly, an electronic component is arranged in a sealed casing. Furthermore, the depressable button which is part of this button assembly is not arranged such as to act directly on the electronic component. Instead, actuating means which are positioned at a back side of the button are provided, wherein these means are adapted to follow a displacement of the button, and wherein the button is allowed to act on the electronic component through these means. The actuating means may be provided in the form of a single rod extending from the button, but more complicated embodiments are also conceivable.

According to the state of the art, the actuating means are arranged outside of the casing in which the electronic component is located. However, it is still possible for the actuating means to act on the electronic component, due to the presence of a resilient member which is incorporated in a wall of the casing. In particular, the actuating means may act on the electronic component by acting on the resilient member, wherein the electronic component is covered by this resilient member, so that a situation is obtained in which the actuating means may operate the electronic component through the resilient member.

In the button assembly according to the state of the art, the problem of steam and/or a liquid reaching the electronic component is solved on the basis of the fact that the electronic component is arranged in a sealed casing. Furthermore, it is still possible to operate the electronic component, namely by ensuring that a portion of the wall of the casing is flexible and may be locally pushed in the direction of the electronic component from outside the casing. However, there is a number of drawbacks associated with the solution according to the state of the art.

In the first place, when the user depresses the button of the known button assembly, the user experiences a kind of spongy feeling due to compression of the resilient member. This is a loss of tactile feedback, on the basis of which the user may get the impression that it is necessary to exert a higher pressure on the button in order to reach a proper depressed position. In general, the loss of tactile feedback results in uncertainty whether a depressed button is actually in a state for actuating the electronic component, or not. In the second place, it is not possible to use the known button assembly and have a durable transmittal of light to the button in case a light source such as a light emitting diode (LED) is positioned in the sealed casing. According to the state of the art, when it is desired to have a light effect in the button, the casing is transparent, and fixed light guides are arranged on top of the casing. In general, a light guides serve for transmitting light from one area to another area on the basis of a phenomenon known as total internal reflection. The light guide is often provided in the form of a rod of a plastic or another suitable material having translucent properties. When light is received at one end of the rod, the light enters the rod, and keeps reflecting on a side wall of the rod while traveling onward until the light reaches another end of the rod. The fact that the light can stay inside the rod is obtained when a refractive index of the rod is higher than a refractive index of its immediate surroundings, which is the case when the rod comprises plastic, and the rod is surrounded by air.

On the basis of the known application of a transparent casing and light guides arranged on top thereof, it is possible to create a desired light effect in the button area. However, in the known configuration, there is a gap between each light guide and the casing, which is susceptible to contamination, and this causes the light transport function of the light guides to get deteriorated over time.

SUMMARY OF THE INVENTION

It is an object of the present invention to provide a button assembly as set out in the opening paragraph, i.e. a button assembly comprising an electronic component, a depressable button, actuating means which are arranged at a back side of the button, a sealed casing enclosing the electronic component, and a resilient member which is incorporated in a wall of the sealed casing, which is designed such that the above-mentioned problem of the spongy feeling when the button is depressed by a user does not occur when this button assembly is applied. It is a further object of the present invention to create an opportunity to have a light guide in the button assembly in such a way that a path extending between the light guide and a light source cannot get dirty.

The objects as mentioned in the preceding paragraph are achieved by a button assembly in which the actuating means comprise an actuating element extending through the resilient member without intermediate space, and in which the actuating element is adapted to act upon the electronic component directly. The actuating element may be connected to the button, or the button may be arranged such as to abut against the actuating element when being put to a depressed state. When the actuating element is arranged such as to act upon the electronic component directly by contacting this component, the tactile feedback which is experienced by a user who presses the button provides a feeling of actually contacting the electronic component, which provides confidence that the electronic component is actually activated. In any case, in the button assembly according to the present invention, there is no need for an application of resilient compressible material in a path between the actuating means and the electronic component, and therefore the button is capable of providing a feeling of direct contact.

Although in the button assembly according to the present invention, the actuating element is extending from the outside of the sealed casing to the inside of the sealed casing, there is no risk of steam and/or a liquid reaching the inside of the sealed casing. The reason is that the actuating element is extending through the resilient member without intermediate space. On the basis of the resilient properties of the resilient member, it is very well possible to have a sealing contact between the resilient member and the actuating element, so that the inside of the sealed casing is protected from external influences.

In a preferred embodiment of the button assembly according to the present invention, the actuating element is provided in the form of a one-piece element which is connected to the button. In this way, it is ensured that when the user depresses the button for changing the state of the electronic component by contacting the component, the user actually experiences a feeling of direct contact to the electronic component.

The actuating element may be supported exclusively by the resilient member. A first advantage of this possibility is that there is no need for additional components for the purpose of providing support. A second advantage of this possibility is that a default position of the actuating element may be defined in this way. Due to the resilient properties of the resilient member, the actuating element is always urged to move back to the default position after the button has been depressed and the actuating element has been displaced deeper into the sealed casing. It is noted that it is advantageous to apply a stop, wherein the default position is accurately defined as a position where abutment to the stop is realized.

On the basis of the fact that it is possible to use the actuating element as a light guide in addition to using the element for acting directly upon the electronic component, the present invention also provides a possibility of having transport of light from the inside of the sealed casing to the outside of the sealed casing, wherein this transport is consistent over time. In particular, the button assembly may further comprise a light source such as a light emitting diode which is arranged in the sealed casing, wherein the actuating means are adapted to act as a light guide. For example, the actuating element of the actuating means may be provided in the form of a rod made of transparent material.

For the purpose of having a light effect in the button area, various ways of allowing a user to see light coming from the actuating means when the light source is in the activated state are feasible. For example, the button may comprise at least one hole for letting out the light, so that the light may shine through this hole. Additionally, an end of the actuating means may be received in the at least one hole of the button, so that the button may have the hole for letting out the light and at the same time may have the look of a fully closed component. Alternatively, the button may comprise at least one transparent portion for letting out the light.

For the purpose of ensuring a tight arrangement of the actuating element through the resilient member, it is advantageous if the actuating element comprises a groove, wherein a ring-shaped portion of the resilient member delimiting a hole in the resilient member for letting through the actuating element is received in the groove. On the basis of the presence of the groove, it is practically impossible for the actuating element to move with respect to the resilient member, as the ring-shaped portion of the resilient member is retained in the groove and delimited by material of the actuating element in the direction in which the actuating element is displaced when the button is depressed. Preferably, in a disassembled state of the button assembly, a diameter of the hole in the resilient member is smaller than a diameter of the groove in the actuating element. In this way, it is achieved that the resilient member is firmly tightened around the actuating element in the assembled state, as the resilient member has a constant inclination to decrease the size of its hole. In addition, it is possible for a height of the ring-shaped portion of the resilient member to be larger than a height of the groove in the actuating element, so that the ring-shaped portion of the resilient member can only be received in the groove of the actuating element in a depressed state, and the material of the resilient member is pressed against edges delimiting the groove under the influence of an inclination of the resilient member to increase its height again. Nevertheless, in practical cases, it may be sufficient to realize a sealing contact between the resilient member and the actuating element only by having the above-described relation of diameters.

In a practical embodiment of the button assembly according to the present invention, the electronic component to be actuated by the actuating element, the light source, and possible other electronic components are connected to a printed circuit board. It is most important to shield such a board from steam and/or a liquid, and therefore, it is preferred if the board is also enclosed by the sealed casing.

Besides a button assembly as described in the foregoing, the present invention also provides a button unit comprising at least two button assemblies. In the button unit, the sealed casings of the various button assemblies may be joined to a single sealed casing. Furthermore, the present invention provides an appliance comprising at least one button assembly or a button unit as mentioned. The at least one button assembly or the button unit may be incorporated in the appliance in such a way that, in a normal operational orientation of the appliance, a front side of the buttons of the at least one button assembly or the button unit has a substantially horizontal orientation. Such orientation of the buttons has the advantage that a user is able to see the buttons from above, so that the user does not need to bend over in order to see the buttons when the appliance is positioned on a kitchen working top, a table or the like. Even in case the appliance is adapted to work with steam and/or a liquid during its operation, there is no risk of the steam and/or the liquid reaching the electronic component to be actuated by the actuating element of the at least one button assembly and possible other electronic components, as these are positioned in a watertight casing.

The above-described and other aspects of the present invention will be apparent from and elucidated with reference to the following description of a button assembly and a button unit according to the present invention.

BRIEF DESCRIPTION OF THE DRAWINGS

The present invention will now be explained in greater detail with reference to the figures, in which equal or similar parts are indicated by the same reference signs, and in which: figure 1 is a perspective view of a button unit according to the present invention; figure 2 is a perspective, cut-away view of the button unit and portions of housing elements of an appliance in which the button unit is incorporated; and figure 3 is a sectional view of one of the button assemblies of the button unit and portions of the housing elements of the appliance.

DETAILED DESCRIPTION OF EMBODIMENTS

Figure 1 shows a button unit 1 according to the present invention. In the shown example, the button unit 1 has three button assemblies 2, wherein a button assembly 2 is an assembly 2 having a depressable button 3 and electronics 4 to be operated by the button 3.

The button unit 1 according to the present invention may be incorporated in any suitable type of appliance in which it is desirable to have two or more depressable buttons for enabling a user of the appliance to control the operation of the appliance. One example of such an appliance is a coffee maker having an on/off button and buttons for setting a quantity of coffee to be made, wherein one button may be associated with a single predetermined quantity and another button may be associated with a double predetermined quantity. It is also possible to use a single button assembly 2 or a number of button assemblies 2 in an appliance, wherein, in the latter case, the button assembles 2 may be arranged in an adjacent fashion, or may be arranged at different positions in the appliance. Figures 2 and 3 illustrate an arrangement of the button unit 1 in an appliance having a base housing part 5 which is closeable by means of a hingeably arranged lid 6, wherein a lever 7 is provided for enabling a user of the appliance to lock and unlock an engagement of the lid 6 to the base housing part 5. The button unit 1 is positioned such that the buttons 3 can be reached at the top of the appliance, and the lid 6 has holes 8 for accommodating the buttons 3 of the button unit 1.

In the shown example, the electronics 4 of each button assembly 2 of the button unit 1 comprise a microswitch 9 and a LED 10, which are mounted on a printed circuit board 11. In order to protect the electronics 4 from external influences, the electronics 4 are arranged in a sealed casing 12. In particular, the sealed casing 12 is a watertight casing, so that it is impossible for a liquid to reach the electronics 4. On the basis of the application of the watertight casing 12 as mentioned, the button unit 1 according to the present invention is especially suitable to be applied in appliances which are using or generating steam during their operation and/or which are using a liquid such as water and/or emitting a liquid during their operation. It is noted that in the case of a button unit 1 comprising at least two button assemblies 2, it is an option to have a single sealed casing 12.

Each button assembly 2 comprises a rod 13 which is suitable for performing two important functions, namely acting on the microswitch 9 when the button 3 is depressed, and transporting light emitted by the LED 10 when being in an activated state to a front side 14 of the button 3, so that the light may be seen from the outside. In the shown example, the button 3 comprises one or more holes 15 for accommodating an end portion 16 of the rod 13, so that the light which is emitted by this end portion 16 when the LED 10 is in an activated state may shine from the button 3. Furthermore, the button 3 is attached to the rod 13. The figures show one of the many ways in which a connection between the button 3 and the rod 13 may be established. According to the shown possibility, the rod 13 is provided with a collar 17, and the button 3 has two arms 18 having a hook-shaped end portion 19 for engaging the collar 17.

The rod 13 is arranged such as to extend all the way from the button 3 to the inside of the sealed casing 12, so that one end portion 20 of the rod 13 is close to the LED 10 for receiving light from the LED 10, and is capable of contacting the microswitch 9. The sealed casing 12 is provided with a hole 21 for allowing the rod 13 to extend to its inside. In order to have a watertight construction, a resilient member 22 is provided, which is arranged in the hole 21 of the sealed casing 12, which has a hole 23 for allowing the rod 13 to extend from the outside of the sealed casing 12 to the inside of the sealed casing 12, and which is adapted to be in close contact with the rod 13 on the basis of its resiliency. The resilient member 22 may be manufactured from any suitable resilient material.

In the shown example, the rod 13 has a groove 24 for accommodating a ring- shaped portion of the resilient member 22. Advantageously, in a disassembled state, a diameter of the hole 23 of the resilient member 22 is somewhat smaller than a diameter of the groove 24, so that it is achieved that once the rod 13 is put in position with respect to the resilient member 22, the resilient member 22 closes tightly around the rod 13 on the basis of an inclination to bring back its hole 23 to the original size. In general, the dimensions of the ring-shaped portion of the resilient member 22 to be placed in the groove 24 of the rod 13 may be chosen such that the ring-shaped portion is compressed once assembly has taken place, so that it is achieved that the material of the resilient member 22 is biased towards the surface of the groove 24, as a consequence of which a watertight fitting of the rod 13 through the resilient member 22 is obtained. As the rod 13 is firmly held by the resilient member 22, there is no need for additional supporting means, as clearly illustrated by figure 1. A default position of the rod 13 in the direction in which the rod 13 is displaceable is defined by means of a stop 25, wherein the collar 17 of the rod 13 may be used for contacting this stop 25, and wherein the default position is the position where the collar 17 abuts against the stop 25. In the shown example, the stop 25 is arranged in the lid 6 of the appliance, as illustrated by figure 3.

When a user depresses the button 3, the rod 13 is displaced in the direction of the microswitch 9, wherein the displacement is allowed for by the resilient member 22, which deforms in the process. As the rod 13 acts on the microswitch 9 by actually contacting the microswitch 9, there is no loss of tactile feedback, and the user directly experiences that the microswitch 9 is operated as a result of the depression of the button 3. When the user releases the button 3, the button 3 is moved back to its default position by the resiliency of the resilient member 22, which urges the resilient member 22 to assume its original position again. As mentioned before, the rod 13 is not only suitable to be used for operating the microswitch 9, but also has a function in serving as a light guide for transporting light emitted by the LED 10 during its operation to the button 3. To this end, the rod 13 is made of a material having translucent properties. The transport of the light through the rod 13 takes place in a manner known perse, namely on the basis of a phenomenon called total internal reflection. As an end portion 20 of the rod 13 is positioned closely to the LED 10, it is achieved that as much as possible light is received from the LED 10, and that an optimal light effect is obtained in the button area.

The button assembly 2 as described in the foregoing offers many advantages. In the first place, this assembly 2 can be used in various types of appliances, as the electronics 4 of this assembly 2 are arranged in a sealed casing 12 and cannot be reached by harmful liquids and/or gases. Even in environments where a liquid such as water may be spilled, the depressable button 3 of the button assembly 2 can be oriented such that its front side 14 is in a horizontal position or close to horizontal position, i.e. in a position in which spilled liquid is likely to enter the assembly 2 through the button hole 8 of a housing 5, 6 for accommodating the assembly 2. In the second place, there is no loss of tactile feedback when a user depresses the button 3 of the button assembly 2, as the assembly 2 comprises a rod 13 extending all the way from the button 3 to the electronic component 9 to be operated. On the basis of the application of a resilient member 22 for retaining the rod 13 in a hole 21 of the casing 12 in a sealing fashion, a loss of watertightness is prevented. Furthermore, the resilient member 22 may serve as a support of the rod 13, wherein it is possible to have a defined default position for the button 3, wherein a stop 25 may be applied. In the third place, the rod 13 is suitable to be used as a light guide, wherein a light source such as a LED 10 may be positioned inside the sealed casing 12 and an end portion 20 of the rod 13 may be positioned closely to the light source. In this way, any desirable light effect in the button area may be realized.

It will be clear to a person skilled in the art that the scope of the present invention is not limited to the examples discussed in the foregoing, but that several amendments and modifications thereof are possible without deviating from the scope of the present invention as defined in the attached claims. While the present invention has been illustrated and described in detail in the figures and the description, such illustration and description are to be considered illustrative or exemplary only, and not restrictive. The present invention is not limited to the disclosed embodiments.

Variations to the disclosed embodiments can be understood and effected by a person skilled in the art in practicing the claimed invention, from a study of the figures, the description and the attached claims. In the claims, the word "comprising" does not exclude other steps or elements, and the indefinite article "a" or "an" does not exclude a plurality. The mere fact that certain measures are recited in mutually different dependent claims does not indicate that a combination of these measures cannot be used to advantage. Any reference signs in the claims should not be construed as limiting the scope of the present invention.

In the foregoing, a button assembly 2 has been disclosed, which comprises an electronic component 9, a depressable button 3 for allowing a user of the button assembly 2 to operate the electronic component 9, actuating means 13 which are positioned at a back side of the button 3, and which are adapted to follow a displacement of the button 3 and to act upon the electronic component 9, a sealed casing 12 enclosing the electronic component 9, and a resilient member 22 which is incorporated in a wall of the casing 12. The actuating means comprise an actuating element 13 extending through the resilient member 22 without intermediate space, wherein the actuating element 13 is adapted to act upon the electronic component 9 directly. In this way, it is achieved that the electronic component 9 to be actuated by the actuating element 13 and possible other electronic components 10, 11 of the assembly 2 are protected from external influences. In particular, as the electronics 4 are arranged in a sealed casing 12, liquids and/or gases are prevented from reaching the electronics 4. This is despite of the fact that the actuating element 13 is allowed to extend from the outside of the casing 12 to the inside of the casing 12. On the basis of the resiliency of the resilient member 22, it is possible to have a sealing contact between the resilient member 22 and the actuating element 13, so that the watertightness of the casing 12 is guaranteed. Hence, the button assembly 2 is suitable to be used in many types of appliances which need to be equipped with a electronic component 9 and a depressable button 3 for allowing a user of the appliance to operate the electronic component 9, including appliances which are adapted to create an environment with steam, water or another liquid during their operation. Furthermore, on the basis of the fact that a portion of the actuating element 13 is present inside the casing 12, it is very well possible to use this element 13 as a light guide, wherein a light source 10 may be arranged in the casing 12 as well. Consequently, the assembly 2 is also suitable to be used in appliances in which it is desired to have a button 3 with a light effect.

Claims

CLAIMS:

1. Button assembly (2), comprising: an electronic component such as a switching device (9), i.e. a device which is adapted to be arranged in an electronic circuit and to assume a state for interrupting the circuit or a state for closing the circuit, a depressable button (3) for allowing a user of the button assembly (2) to operate the electronic component (9), actuating means (13) which are positioned at a back side of the button (3), and which are adapted to follow a displacement of the button (3) and to act upon the electronic component (9), a sealed casing (12) enclosing the electronic component (9), and a resilient member (22) which is incorporated in a wall of the sealed casing (12), wherein the actuating means comprise an actuating element (13) extending through the resilient member (22) without intermediate space, and wherein the actuating element (13) is adapted to act upon the electronic component (9) directly.

2. Button assembly (2) according to claim 1, wherein the actuating element (13) is provided in the form of a one-piece element which is connected to the button (3).

3. Button assembly (2) according to claim 1, wherein the actuating element (13) is supported exclusively by the resilient member (22).

4. Button assembly (2) according to claim 1, further comprising a light source such as a light emitting diode (10) which is arranged in the sealed casing (12), wherein the actuating means (13) are adapted to act as a light guide, i.e. to transport light which is emitted by the light source (10) when the light source (10) is in an activated state.

5. Button assembly (2) according to claim 4, wherein the actuating element (13) of the actuating means is provided in the form of a rod made of transparent material.

6. Button assembly (2) according to claim 1, wherein the actuating element (13) comprises a groove (24), and wherein a ring-shaped portion of the resilient member (22) delimiting a hole (23) in the resilient member (22) for letting through the actuating element (13) is received in the groove (24).

7. Button assembly (2) according to claim 6, wherein, in a disassembled state thereof, a diameter of the hole (23) in the resilient member (22) is smaller than a diameter of the groove (24) in the actuating element (13).

8. Button assembly (2) according to claim 1, further comprising a printed circuit board (11), wherein the electronic component (9) is connected to the printed circuit board (11), and wherein the printed circuit board (11) is also enclosed by the sealed casing (12).

9. Button unit (1), comprising at least two button assemblies (2) according to claim 1.

10. Button unit (1) according to claim 9, wherein the sealed casings (12) of the various button assemblies (2) are joined to a single sealed casing.

11. Appliance, comprising at least one button unit (1) according to claim 10.

12. Appliance according to claim 11, wherein, in a normal operational orientation of the appliance, a front side (14) of the buttons (3) of the button unit (1) has a substantially horizontal orientation.

13. Appliance, comprising at least one button assembly (2) according to claim 1.

14. Appliance according to claim 13, wherein, in a normal operational orientation of the appliance, a front side (14) of the button (3) of the at least one button assembly (2) has a substantially horizontal orientation.