DE202007018958U1 - touch screen - Google Patents

Abstract

Touch-sensitive sensor comprising:
a control circuit board having first and second sides;
a sensor substrate having a connection terminal; and
a resilient electrical connector for establishing an electrical connection between the control circuit board and the connection terminal, wherein the resilient electrical connection element is applied to the first side of the control circuit board and is arranged so that it extends over an edge of the control circuit board and in one direction to the second side the control circuit board to connect to the connection terminal of the sensor substrate.

Description

Background of the invention

The Invention relates to touch-sensitive sensors, also known as touch screens, and in particular on the mediation of electrical contact between a detection element and a sensor circuit in such a sensor.

Of the Use of touch-sensitive sensors is increasing common. Examples include the use of touch sensors in Laptop computers instead of mouse pointing devices, and as Control panels for receiving user input for controlling a Device or apparatus, both in the household and portable.

touch-sensitive Sensors are often preferred to mechanical devices because they provide a more resilient interface and are often considered aesthetically pleasing. In addition, because touch-sensitive sensors have no moving parts for accessibility for the user they are less susceptible to wear and tear as their mechanical counterparts and can be inside provided a sealed outer surface become. This makes their use particularly attractive where there is danger that dirt or liquids in a controlled device penetration. In addition, touch-sensitive Sensors, other than mechanical interfaces made translucent become. There is an increasing desire to provide more translucent Sensors, as these are over an ad for deployment a touch-sensitive screen who can display information to a user and can respond to a user who is on specific areas of the ad indicated.

1 shows schematically in perspective view an ordinary control plate 2 containing a capacitive touch-sensitive sensor. The control plate 2 includes a cover plate 8th , a detection element 4 and a board 6 , The detection element 4 and the board 6 are at the bottom of the cover plate 8th attached. (The page that is inaccessible to a user during normal use is considered the bottom).

The detection element 4 based on a translucent flexible plastic substrate. The substrate comprises a detection area 10 and a connector plug part 12 (also known as an end connector). A translucent conductive material is deposited on the substrate around sensor electrodes 14 and tracks 16 for conducting signals between the sensor electrodes and the circuit board 6 via the end connector 12 provide. The tracks 16 are in an area towards the end connector 12 tinned to provide a connection area 18 ,

The board 6 carries driver circuits (not shown) for the sensor electrodes 14 and corresponding calculation circuits (also not shown) for determining the location of a touch. The driver and calculation circuits can be collectively referred to as measurement circuits.

The cover plate 8th is translucent in an area corresponding to the sensor area part of the detection element 4 is superimposed, and opaque over the rest of their surface. Thus, a display screen (not shown) mounted behind the sensing element is visible to a user while the board 6 and the end connector part 12 of the scope it is not.

When assembling the control plate 2 must have an electrical connection between the detection electrodes 14 of the detection element 4 and the measuring circuits on the board 6 getting produced. This is done by introducing the connection area 18 of the end connector 12 of the detection element 4 into a socket on the board 6 ,

2A schematically shows a perspective view of the underside of a part of the board 6 on which a socket 20 is appropriate. The socket 20 is a ZIF connector of the type provided by Tyco Electronics. The socket comprises a housing part 24 and a sliding cover 26 , The housing part 24 includes metal contacts 22 leading to pins on the bottom of the case 24 for soldering to the board 6 by connecting. The socket 20 is shown in its open arrangement, in which the sliding cover 26 from the board 6 extends away. In this arrangement, the socket is for receiving the connection area 18 of the end connector 12 ready. To connect, the connection area becomes 18 in a slot opening 28 between the housing part 24 and the sliding cover 26 pushed (as in the 2A indicated by the direction of the arrow) and the sliding cover 26 closed.

2 B is similar to that 2A and can be understood with their help, but shows the jack 20 in its closed arrangement, in which the sliding cover 26 on the board 6 has been pushed to after the end connector 12 in the slot opening 28 has been introduced. In this closed arrangement, the verb pushes dung region 18 of the end connector 12 against the metal contacts 22 the socket 20 for making the necessary electrical connections and also serves to hold the end connector in place.

Of the The mechanism described above provides robust and reliable electrical connections between touch-sensitive Safe and secure elements and their associated measuring circuits. For Production lines of large series, however, may be the process connecting by inserting the end connector in the socket and closing the sliding cover relative be slow to implement and it requires relatively complex operations, which makes it difficult to automate.

One another well-known way, a board to a detection element in to connect to a touch sensing element, is based on the placement of the board in a distance ratio with respect to the sensing element and providing a conductive Foam column to between the board and the sensing element to connect [1]. However, this approach requires again relatively complex operations to the conductive foam columns during assembly and as well means the necessary distance ratio that the Board not flush with the detection element mounted can be. This not only means that the space requirement is higher is, but also means that the board is not easy to one Cover plate or the detection element itself can be glued, because a distance application is needed.

Summary of the invention

According to one The first aspect of the invention is a touch-sensitive Sensor provided, comprising: a control circuit board with opposite first and second pages; a sensor substrate having a connection terminal; and a resilient electrical connection element for producing a electrical connection between the control circuit board and the Connection terminal, wherein the resilient electrical connection element is applied to the first side of the control circuit board and is arranged so that it over the edge of the control circuit board and toward the second side of the control circuit board protrudes to to connect to the connection terminal of the sensor substrate.

Therefore can be the electrical connection between the control circuit board and the sensor substrate during the construction of the touch-sensitive Sensors are made by the control circuit board by simple Press is brought into position. Because further no electrical Connections are associated with the second side of the board, This side of the board is able to flush with one Support structure for the board to lie. The support structure For example, the sensor substrate itself or a separate one Cover plate, where the sensor substrate and the control circuit board both are attached. This in turn makes for a light Construction, since a simple adhesive layer can be used to the Board without requirement of "gaps" or Spacers for housing circuit elements on the Side of the control circuit board attached to the sensor substrate / cover plate is attached.

The resilient electrical connection element may be in the form of a metal leaf spring to be provided. This is a very simple and reliable one Way of providing a good electrical connection with adequate Spring force, and to the control circuit board by conventional Soldering (by hand or automated) can be attached.

The Spring force of the electrical connector helps to make a reliable Ensure connection with the connection terminal of the sensor substrate. To further improve the reliability of the compounds can be a part of the metal leaf spring that connects to the connection of the sensor substrate connects, be forked.

to further help to ensure a good electrical connection and reducing wear / corrosion may be the connection port of the sensor substrate comprise a carbon plate.

The resilient electrical connection element can be placed like this Be it over an outer edge of the control circuit board protrudes or may be set up so that it over an inner edge protrudes, for example, an edge of a hole that especially for the passage of the resilient electrical connection element has been provided.

Of the Touch-sensitive sensor can be of any conventional Be kind, for example, the detection element can be capacitive or resistance-based. The touch-sensitive Sensor can have a translucent area to rest on Have display screen.

Numerous electrical connections between the control circuit board and the sensor substrate can be made in the same way. For example, the touch-sensitive sensor may further comprise at least one further connection terminal on the sensor substrate and at least one a further resilient electrical connector mounted on the first side of the control circuit board and arranged to extend beyond the edge of the control circuit board and in a direction toward the second side of the control circuit board to communicate with corresponding ones of the at least one further connection terminal of the control circuit board Sensor substrate to connect.

According to one second aspect of the invention is a device / device provided, the / a touch-sensitive sensor according to the first aspect of the invention includes.

According to one third aspect of the invention is a touch-sensitive A sensor provided, comprising: a control circuit board; a sensor substrate with a connection port; and a resilient electrical connection element to Making an electrical connection between the board and the sensor substrate, wherein the resilient electrical connection element includes a supernatant for placement within a corresponding recess is arranged in the control circuit board.

The Providing the resilient electrical connection element with a supernatant, in a corresponding recess Placing the control circuit board can help in the probability to reduce that springy electrical connector creeping or lifting off the control circuit board using it.

According to one The fourth aspect of the invention is a device provided, the / a touch-sensitive sensor according to the third aspect of the invention includes.

Brief description of the drawings

To the better understanding of the invention and to show how it can now be put into practice, is now exemplary With reference to the accompanying drawings, in which:

1 schematically shows in perspective view a known control plate, which includes a touch-sensitive sensor;

2A and 2 B schematically perspective views of a female connector of the control panel 1 demonstrate;

3 schematically shows in perspective view a detection element for use in a control plate with a touch-sensitive sensor according to an embodiment of the invention;

4 in a perspective view schematically shows a control plate, which is a detection element of 3 includes;

5 in a perspective view schematically a part of the control panel 4 in enlargement shows;

6A respectively 6B Sectional views of the part of in 5 shown control panel after and shortly before assembly show;

7 in perspective view schematically a strip of eight resilient electrical connection elements for use in the control panel 5 shows; and

8A -C schematic plane, lateral and front elevations of in 7 shown strip of resilient electrical connecting elements show.

Detailed description

3 shows in perspective view schematically a detection element 32 for use in a touch-sensitive sensor according to a first embodiment of the invention. In this example, the detection element is designed for use in a control plate for a domestic dishwasher. In the 3 shown view is a back view. "Backside" refers to the side away from a user in conventional use. Terms like "before" and "behind" should be understood similarly.

The detection element 32 is a capacitive sensing element and includes a translucent central portion that defines a sensor area 34 and a non-translucent outer edge region 36 , The detection element 32 is made of a flexible plastic sensor substrate with translucent sensor electrodes deposited thereon (not visible in FIG 3 ) educated. The arrangement of sensor electrodes may be conventional, for example, individual sensors or a grid-like arrangement may be used. The sensor electrodes are connected to corresponding ones of the connection terminals 38 , in this case eight of them, on the substrate over as needed within the translucent coverage area 34 or the outer edge region 36 connected conductive tracks. The tracks, at least their parts within the translucent coverage area 34 , are also translucent. The connection connections 38 are provided by carbon platelets in conjunction with the corresponding conductive tracks.

When used, the translucent central detection area is located 34 on a display screen. The display screen provides a user with choices related to the operation of the device / device in which the display screen and the control panel are installed, that is, a dishwasher in this case. The user selects choices by placing his finger (or other object) on the corresponding areas of the screen. The position of the user's finger is determined via the position touch-sensitive sensor and the dishwasher responds accordingly.

4 shows in front perspective view schematically a control plate 40 in which the detection element 32 out 3 built according to one embodiment of the invention. In addition to the detection element 32 includes the control plate 40 a printed circuit board (PCB) 42 and a glass cover plate 44 , The PCB comes with a variety of electrical connectors 48 for making electrical connections between the board and the connection terminals 38 of the detection element 32 provided. In this example, two electrical connection elements are associated with each connection terminal. This redundancy ensures increased reliability. For clarity, only the electrical connection elements 48 , which are the four connection terminals in the foreground of the 4 are assigned identified by reference numerals. However, similar electrical connection elements are associated with the connection terminals in the background of the figure.

The cover plate 44 is in 4 highest, but translucent over its entire area and therefore not clearly visible in the figure. In practice, the cover plate would normally be translucent only over the area of the display screen and opaque everywhere else. This allows the visibility of the underlying display screen while the rest of the interior of the dishwasher remains hidden from view during normal use. In addition, it is noted that in some cases the control plate does not rest on a display screen and therefore the cover plate 44 can be opaque over its entire surface. In such cases, the sensor electrodes and the traces of the sensing element 32 also non-translucent.

The PCB 42 carries circuits for driving, for signal reception and processing of the detection element 32 so that the occurrence of a touch above the touch-sensitive sensor can be detected. These circuits are collectively referred to herein as measuring or control circuits. The measuring circuits may be of any conventional type suitable for the type of sensing element used. The PCB may also carry circuits related to the usual functioning of the dishwasher.

5 schematically shows a rear perspective view of a part of in 4 shown control plate in magnification. The part shown includes four of the connection terminals 38 of the detection element 32 and the associated resilient (spring-loaded) electrical connectors 48 , In this example, there are two electrical connection elements 48 (that is, four "contact fingers") to each connection port 38 , This can be useful because if an electrical connector 48 (or one of its "contact fingers") breaks or misaligned to its corresponding connection terminal (eg, carbon plate), it is likely that there are a sufficient number of other connection points to make good electrical contact.

6A shows a sectional view of the part of in 5 shown control plate 40 which runs along the line XX '. The cut in 6A is with the front of the control panel 40 (ie, the page accessible to a user during normal use) is shown at the top.

The PCB 42 and the detection element 32 are of cooperative design, so that their edges are adjacent to each other in the area of the spring-loaded electrical connectors 48 run. The electrical connection elements 48 are on the PCB 42 with solder joints 50 attached. The electrical connectors are near an edge of the PCB 42 placed and arranged so that they over the edge and away from the edge in a direction on the cover plate 44 to extend (that is, downward with respect to in 5 shown orientation, upward with respect to in 6A shown orientation). Therefore, the electrical connection elements 48 designed, their corresponding connection connections 38 to contact, allowing an electrical connection between the circuits on the PCB 42 and the sensor electrodes on the detection element 32 over the spring-loaded electrical connection elements 48 will be produced.

6B is similar to that 6A and can be understood, but shows the arrangement of the control plate 40 during assembly at a point just before the PCB 42 on the cover plate 44 is attached. In this phase of assembly is the detection element 32 in place on the cover plate 44 fastened by means of a suitable adhesive layer. The PCB 42 is offered just above, ready to be pressed on the cover plate, as indicated schematically by the arrow 52 displayed. The PCB 42 (and / or the corresponding part of the cover plate 44 ) is provided with a layer of adhesive material so that it will adhere to the cover plate when pressed into contact therewith.

How out 6B can be seen, is the spring-loaded electrical connection element 48 arranged such that prior to assembly, the sprung connecting element over the edge of the PCB 42 from one side (the side where it is soldered (lowest in 6B )) beyond the other side (the side of the PCB to be attached to the cover plate). Therefore, if the PCB 42 during assembly against the cover plate 44 is pressed, the spring-loaded electrical connection elements touch the appropriate connection connections 38 of the sensing element before the PCB 42 the cover plate 44 touches and sticks to her. The resilient nature of the spring-loaded electrical connectors 48 means that they bend away and it's the PCB 42 allow yourself to continue on the cover plate 44 to move. So if the PCB 42 touches the cover plate and adheres to it, are the spring-loaded electrical connection elements 48 resilient against the corresponding connection terminals 38 biased. This ensures the production of good electrical contact without the need for any additional fastening.

This will make an electrical connection easy by pushing the PCB 42 made in its place, without the need for a separate operation, in which an end connector with a socket as in the 1 . 2A and 2 B is shown connected. In addition, the electrical connection is automatically established by the electrical connectors extending "backwards" in a direction beyond the PCB's own thickness, without any attachment of components or connections on the side of the PCB 42 against the cover plate 44 requirement. Since the PCB can lie flush with the cover plate, it can be attached with a simple adhesive layer.

7 schematically shows a perspective view of a strip 60 of eight spring-loaded electrical connectors 48 for soldering to a like in 5 PCBs are ready. The 8A . 8B and 8C show schematic views of the strip 60 , which were taken along the z, y, and x axes, as shown at the top left in 7 indicated. The 8A . 8B and 8C show dimensions of the strip 60 that could be used in a typical application. It should be understood, however, that the sprung electrical connectors of the invention are per se scalable and that various different sizes and relative shapes can be used.

The stripe 60 includes a disposable backbone part 66 , on which eight spring-loaded electrical connection elements 48 are attached. The spine part 66 serves as a stiffener and to hold the electrical connectors in place in a plane on the PCB during assembly, thereby allowing easy handling of the strip of fasteners 48 , In this example, the strip is 60 punched from a phosphor bronze sheet (optionally coated for corrosion reduction, for example, preferably with gold or platinum, etc.) and at the lines F1, F2 and F3 (as dashed lines in Figs 7 and 8A shown) around the in 8B bent amounts to provide the desired shape.

Because of the eight spring-loaded electrical connectors 48 initially provided as a single strip, they are thus easier to handle during manufacture / assembly. That's because the strip 60 can be easily held on its backbone against the PCB, so that all electrical fasteners 48 placed in their required positions in a single assembly step. Each electrical connection element 48 can then be soldered to suitably placed platelets on the PCB. The placement of the strip and soldering can be automated, for example, by using an infrared reliquefaction process in a conventional PCB assembly robot. Once the electrical connectors 48 can be soldered in place, the disposable backbone 66 be bent so that the now separate electrical connection elements 48 stay in their place. This can be done by providing a fatigue or fracture line 64 at the point where each electrical connector is connected to the disposable spine (tab rail). The predetermined breaking line can be provided, for example, by scratching / scoring or by partial etching of the strip.

This includes each electrical connection element 48 ultimately a leaf spring with a fixed part 72 for attachment to the PCB and a loose part 74 to extend beyond the edge of the PCB and to connect to the connection terminals 38 of the detection element 32 ,

In this example, the corresponding fixed parts with openings 68 provided by the liquid solder during manufacture to improve the solder joint can flow. In addition, in this example, the fixed parts 72 with tabs 70 provided, which bent on the PCB can be to enter into corresponding recesses on the surface of the PCB. These tabs provide for improved mechanical coupling between the electrical connectors 48 and the PCB and reduce the likelihood that the solder joints will separate over time. In the in 7 example shown are the tabs 70 on the side edges of the fixed parts 72 the electrical connection elements 48 located. However, in other examples, the tabs may be in a middle position of the electrical connectors 48 to be provided. These tabs may as well as or in addition to tabs on the side edges as in 7 shown to be present. For example, the tabs on an inner edge of the openings 68 to be provided. This allows the openings 68 are not formed by a complete punching, but by a U-shaped or similar shaped section, so that the middle part of the US is then bent to provide the tab and thus the opening 68 releases. It may be advantageous to place the tabs in a central area to reduce any susceptibility to distortion from twisting forces. For example, if only one tab per electrical connector 48 should be provided and this tab is located along a side edge, the likelihood that the opposite edge of the PCB dissolves. The likelihood that one of the sides will break can be reduced by centralizing the tab.

The free parts 74 the electrical connection elements 48 are bent on the line F2 to angled against a plane containing the side of the PCB, which is opposite to the side of the PCB, to which they are attached. Further, each of the free parts 74 bifurcated (that is, to provide two "contact fingers") to provide two contact points that are nearly mechanically independent and to improve contact reliability. Each of the two ends of the bifurcated free part is bent upwards at F3 so that it is the outer side of the bend at F3 that connects the corresponding connection 38 at the detection element 32 touched. This provides a connection point that can slide along the surface of the connection terminals when the sprung electrical connection elements 48 bent during assembly without causing excessive damage.

you It should be clear that although the exemplary one described above Incarnation the production of electrical connections between a control circuit board and a detection element in a capacitive touch-sensitive Sensor in a dishwasher relates to the invention for making electrical connections in any type of device or device with a resistance or capacity-based touch-sensitive sensor (single or multi-layered, for example, two-sided, can be) can be used. In all Cases, the detection element and the control circuits on the PCB of any conventional type according to the present invention.

Furthermore one should be aware that the cover plate and the detection element can be provided as a single element. This means that sensor electrodes directly on the inside (the means, on the user away in normal use Side) of the cover plate can be deposited, wherein the appropriate lanes and connection connections as well are deposited on the inside of the cover plate. So that can this arrangement can be regarded as an arrangement in which it is more or less no cover plate gives. Instead, the substrate of the sensing element provides even for the protective and external aesthetic Tasks of the cover plate, and the PCB is directly on the sensing element substrate in Attached to the vicinity of the connection terminals.

you should be aware that the edge of the PCB, in the neighborhood the connection terminals of the detection element are provided, no outer edge of the PCB must be, but an inner edge an opening in the PCB. The opening can be large enough, for example, the entire touch-sensitive area accommodate the detection element, or can simply a hole be in the PCB big enough for the yielding one electrical contact to the passage is.

Even though specific embodiments of the invention have been described are, you should be aware that many changes / additions and / or substitutions can be made without departing from the scope to deviate from the invention.

Sources

• [1] DE 201 19 700 U1 (EGO Control Systems GmbH & Co.)

QUOTES INCLUDE IN THE DESCRIPTION

This list The documents listed by the applicant have been automated generated and is solely for better information recorded by the reader. The list is not part of the German Patent or utility model application. The DPMA takes over no liability for any errors or omissions.

Cited patent literature

• - DE 20119700 U1 [0056]

Claims (19)

Touch-sensitive sensor comprising: a Control circuit board with first and second sides; a sensor substrate with a connection port; and a springy electric Connecting element for producing an electrical connection between the control circuit board and the connection terminal, wherein the resilient electrical connection element on the first side the control circuit board is applied and is arranged such that It is located on one edge of the control circuit board and in one Towards the second side of the control circuit board, to connect to the connection terminal of the sensor substrate. Touch-sensitive sensor according to claim 1, wherein the resilient electrical connection element is a metal leaf spring is. Touch-sensitive sensor according to claim 2, wherein a part of the metal leaf spring connected to the connection terminal of the sensor substrate connects, forked. Touch-sensitive sensor according to a of the preceding claims, wherein the resilient electrical Connecting element on a circuit board with a solder joint is applied. Touch-sensitive sensor according to a of the preceding claims, wherein the resilient electrical Connecting element includes a supernatant, such it is arranged within a corresponding recess is placed in the control circuit board to a mechanical coupling provide. Touch-sensitive sensor according to a of the preceding claims, wherein the connection terminal of the sensor substrate comprises a carbon plate. Touch-sensitive sensor according to a of claims 1 to 6, wherein the edge has an outer edge the control circuit board is. Touch-sensitive sensor according to a of claims 1 to 6, wherein the edge is an inner edge of an opening in the control circuit board is. Touch-sensitive sensor according to a of the preceding claims, further comprising a cover plate on which the second side of the control circuit board and the sensor substrate are attached. Touch-sensitive sensor according to claim 9, wherein the sensor substrate on the cover plate by an adhesive layer is attached. Touch-sensitive sensor according to claim 9 or 10, wherein the control circuit board on the cover plate by an adhesive layer is attached. Touch-sensitive sensor according to a of claims 1 to 11, wherein the sensor substrate on Capacitance measurement based sensor substrate is. Touch-sensitive sensor according to a of claims 1 to 11, wherein the sensor substrate on Resistance measurement based sensor substrate is. Touch-sensitive sensor according to a of the preceding claims, wherein at least a part the sensor substrate is translucent. Touch-sensitive sensor according to a of the preceding claims, further comprising at least one further connection terminal on the sensor substrate and at least one further resilient electrical connection element, which is applied to the first side of the control circuit board and is arranged so that it extends over the edge of Control circuit board and in one direction to the second side of the Control circuit board to extend to comply with at least to connect another connection terminal of the sensor substrate. Device that has a touch-sensitive sensor according to one of the preceding claims includes. Touch-sensitive sensor comprising: a Control circuit board; a sensor substrate having a connection terminal; and one resilient electrical connection element for producing a electrical connection between the control circuit board and the Sensor substrate, wherein the resilient electrical connection element includes a projection arranged such that he within a corresponding recess in the control circuit board is placed. A touch-sensitive sensor according to claim 17, further comprising at least one further connection terminal on the sensor substrate, and at least one further resilient electrical connection element for establishing an electrical connection between the control circuit board and the sensor substrate, wherein the at least one further resilient electrical connection element includes a projection which is such is placed within a corresponding recess in the control circuit board. Device that has a touch-sensitive sensor according to claim 17 or 18.