WO1999048043A1

WO1999048043A1 - Touch panel for a monitor, comprising transducers and aligned pretensioning elements

Info

Publication number: WO1999048043A1
Application number: PCT/EP1999/001717
Authority: WO
Inventors: Reinhard Urbasik
Original assignee: Höft & Wessel AG
Priority date: 1998-03-16
Filing date: 1999-03-16
Publication date: 1999-09-23
Also published as: DE19811394A1; AU3145399A

Abstract

According to the invention three or four transducers (3) positioned between a frame (4) and a plate or convex pane (1) are held in an adjustable state of pretension (7) by aligned elements (6). Said system is used as a 'mouse' in front of the screen of a monitor.

Description

TOUCH PANEL FOR MONITOR WITH POWER CONVERTERS AND ALIGNING TENSIONING ELEMENTS

The invention relates to a device for locating pressure forces exerted on a surface.

It is known (DE 195 02 956 A1) to build in front of the display unit of a machine control a touch-sensitive plate which is able to determine on its flat surface the location where the plate is touched with light pressure. The position is expressed there in xy coordinates and transferred to a computer. Depending on the point of contact, this determines application-specific processes. A force sensor is installed on each corner of the plate to determine the touch coordinates, hereinafter referred to as the sensor. In order to avoid any starting point for vandalism in the known arrangement, the plate can be step-shaped and the frame can be formed across the step with a common surface. The part of the plate covered by the frame is held at the corners of the plate between a sensor and a spring element aligned with the sensor.

The invention has for its object to provide a device with a touch-sensitive surface, the construction and operation of which is improved compared to the prior art. This object is achieved by the features defined in claim 1. Further developments are characterized in the dependent claims. 2

In principle, the invention consists in a device for locating pressure forces exerted on a flat or curved, essentially dimensionally stable surface in that a body containing or supporting the surface or a flat or curved disk is provided that the disk has at least three over the Surface-distributed pressure-sensitive sensors are assigned to the sensors on a reference body, for example a frame, arranged or mounted on or on this, that body or disc and reference body or frame are connected to one another by pretensioning elements, and that the pretensioning elements are arranged laterally offset relative to the sensors.

It is thereby achieved that the sensitivity of the sensors can be better used and that the assembly of the structural unit from the body exposed to the compressive forces and the reference body forming the cover for the sensors or from the frame and pane is simplified. The pane can be transparent or opaque, it can be a plate, but it can also be a curved pane and even a pane designed as a lens. After all, the pane itself can also be a flat screen. Vandalism can be avoided by a front panel of the housing or frame, which extends to the edge of the body or the pane and is sealed against this edge. When using a disc that is curved outwards, the diaphragm can also be curved accordingly.

The shape of the surface can be chosen almost arbitrarily. For example, it can be rectangular or oval. It can be flat, but it can also be curved. For a more detailed explanation of the invention, several exemplary embodiments are described below with reference to the drawings, for example. These show in:

Figure 1 is a basic front view of a device according to the

Invention, Figure 2 is a sectional side view of Figure 1, Figure 3 is an illustration of the power system, Figure 4 is a rear view of the front window of FIG. 1 without

Preloading elements, but with positioning parts, FIG. 5 shows a sectional side view of FIG. 4, FIG. 6 shows a view of the front window according to FIG. 1 with positioning parts for the preloading elements, FIG. 7 shows a side view of FIG. 6, FIG. 8 shows a view of the front window according to FIG. 1 With

Guide elements for the pane, FIG. 9 is a side view of FIG. 8, FIG. 10 is a view of the front pane according to FIG. 1 with sensors as

Anchoring elements for fastening material, FIG. 11 is a side view of FIG. 12, FIG. 12 is a view according to FIG. 1 with holding or pretensioning elements as anchoring elements for fastening material, FIG. 13 is a side view of FIG. 12, FIGS. 14 to 19 and FIGS. 21-24 different Embodiments of the

Preload elements Figure 20 shows a detail from Fig. 19 Figure 25 shows the side view of a locating device with a flat

Screen (display) arranged transparent body, Figure 26 is the sectional side view of a monitor with a superior

Locating device, FIG. 27 is a front view of another embodiment than FIG. 1. 4

FIG. 1 shows a basic front view of a device according to the invention for locating pressure forces F which are exerted on an essentially dimensionally stable, that is to say non-compliant, surface 1 of a body 2 designed as a disk. The body 2 is assigned four pressure-sensitive sensors 3, which are supported on a reference body 4. The reference body 4 is connected to the body 2 to form a unit, in particular clamped, by means of two biasing elements 6 which are laterally offset relative to the sensors 3. The prestressing elements 6 and the pressure-sensitive sensors 3 are dimensioned such that the pressure-sensitive sensors 3 are prestressed. In Fig. 1, the biasing elements 6 act for this purpose resiliently on the connection of parts 2 and 4, as indicated by the springs 7 in Fig. 2. However, it is also possible to mount the sensors 3 on their own or in addition in a resilient manner. A sensor arrangement with at least three sensors 3 makes it possible to determine the coordinates which are exerted by a pressure force F on the surface 1 of the body 2. The surface 1 of the body 2 can with any, in the figure. 1 not drawn symbols can be designed. As a result, the surface 1 of the body 2 becomes an operator interface in which certain fields are simulated in their function as digital, analog pressure-sensitive switches or potentiometers. In this case, the two bodies 2 and 4 could be made continuously opaque, for example adjacent disks.

FIG. 2 shows a side view of the device shown in FIG. 1 with two such adjacent disks. If the body 2 is made of transparent material, the reference body 4 is designed like a frame, as indicated by the edge 5 in FIG. 1. Such a frame-like design of the reference body 4 behind a transparent pane is shown in Fig. 1 by the visible inner edge 5 of the frame. Such an execution can be in front of a monitor screen 5

be arranged. As a result, the respective screen display of the monitor or display can be used as the user interface.

3 shows a force system acting on the sensors 3 when a force F occurs in connection with a corresponding coordinate system. The force F is transmitted to the sensor arrangement from the sensors 3 with the aid of the essentially dimensionally stable body 2 in accordance with the general statics for a flat force system (in FIG. 3). The force F causes a spatial displacement of the body 2 essentially perpendicular to the surface 1 in the direction of the sensors 3. This body 2 distributes the force F to the individual sensors 3 in accordance with the center of gravity of the force F. For such a force system, Assume linear characteristic curve with few equations for each point of the surface 1 of the body 2 calculate the respective point of application of the force F. A first equation assumes that the sum of all forces acting on the body 2 (ie force F and the counterforce exerted by the sensors 3) is zero. The other two equations give the moments in the x direction and the y direction of the xy plane separately. The x, y vectors practically span a plane which, with a good approximation, corresponds to a parallel displacement of the area spanned by the contact / measurement points of the force sensors. Each force F acting on the surface 1 of the body 2, that is to say also obliquely acting forces, as shown in FIG. 3, allows a detection of this force F and a transmission of the vertical component Fz of this force F with corresponding moments in x or y Direction towards the sensors 3 (four in FIG. 1) distributed over the edge region of the body 2. The forces Fx and Fx shown in FIG. 3 are parasitic forces which are disruptive in the first equation and should be rendered ineffective or at least small in their effect being held. Some possibilities for minimizing such parasitic forces Fx and Fy are given below. FIG. 4 shows an arrangement of positioning parts 8 on the back of the body 2 for securing the position of the body 2 relative to the sensors 3 held by the reference body 4 or fastened thereon.

FIG. 5 shows the sectional side view of FIG. 4.

6 shows an arrangement of positioning parts 9 on the front of the body 2, for example on the surface 1, for securing the position of the body 2 relative to the holding elements 6 joining the reference body 4 and the body 2.

FIG. 7 shows a sectional side view of FIG. 6.

FIG. 8 shows an arrangement of positioning or guiding parts 10 next to the edge of the body 2, which prevent the body 2 from moving in relation to the reference body 4 in the xy plane. These guide parts 10 are attached to the body or frame 4, for example.

FIG. 9 shows a sectional side view of FIG. 8, which clearly shows how the guide parts 10 are attached to the body or frame 4.

10 shows a fastening of the body 2 directly to the sensors 3, which thus prevent movement of the body 2 relative to the reference body 4 in the xy plane. For this purpose, the sensors 3 are designed as bending beams that can carry or accommodate special fastening material in assembly stations 31, 32.

FIG. 11 shows a sectional side view of FIG. 11, which clearly shows how the sensors 3 are designed as bending beams and are connected to the body 2. 7

12 shows a fastening of the body 2 directly to the holding elements 6 at assembly points 61, which thus likewise prevent the body 2 from moving relative to the reference body 4 or to the sensors 3.

FIG. 13 shows a sectional side view of FIG. 11, which clearly shows that the prestressing elements additionally carry the fastening material and are connected to the body 2. When considering FIG. 13, it should be noted that the prestressing elements are laterally offset relative to the sensors, so that the fastening material does not engage in the sensors.

In the devices according to the figures 1-13 described above, the individual components such as the bodies 2 and 4, the sensors 3 and the positioning parts 8-10 are combined by the prestressing elements 6 into one unit, to form a system with which any in the room to detect extended force on the surface 1 and to transfer it into the coordinate system of the device. The force component Fz acting perpendicularly on the surface 1 determines the location of the coordinate sought.

Because of the importance of the biasing elements for the accuracy of the localization, some exemplary embodiments are shown and described below. FIGS. 14 to 19 show such different exemplary embodiments of the prestressing elements 6.

In FIG. 14, the holding element 6 has a clip 12 that surrounds the edge 11 of the body 2 and a bolt 13 arranged in the reference body 4 perpendicular to the surface 1 of the body 5, which is connected to the clip 12 by a lever arm 14 on the side of the surface 1 is movable relative to the reference body 4 against the force of one or more springs 15. This bolt 13 has an internal thread 16 8th

Mistake. The spring force is thereby adjustable by means of an adjustable screw 17. The inner surface of the lever arm 14 extends essentially in that plane of the surface 1 on which the pressure forces to be located act.

In FIG. 15, the holding element 6, as in FIG. 14, has a clip 12 which surrounds the edge 11 of the body 2 and a bolt 13 which is arranged in the reference body 4 perpendicular to the surface 1 of the body 2 and which, relative to the reference body 4, counteracts the force of or more springs 15 is movable. 15, this bolt 13 is provided with an internal thread 16, which allows the spring force to be adjusted by means of an adjustable screw 17. In contrast to FIG. 14, clamp 12 and bolt 13 are connected here by a lever arm 14, which is arranged on the side of body 2 facing away from the force. In both figures, the sensors 3 forming the counter bearing to the holding elements 6 are not shown. Body 2 and reference body 4 therefore seem to be freely movable against each other. This is not the case in the following figures. The sensors shown there are always laterally offset against the biasing elements 6 or clamps 12.

16 shows a device in which the sensors 3 are fixedly attached to the reference body 4 and touch the side of the body 2 facing away from the compressive force F. A stable lever arm 14, which is firmly connected to the bolt 13, which is resiliently mounted in the reference body 4, presses the body 2 in the direction of the sensors 3 and causes a preload for the latter. This is adjustable by means of screw 17 and spacer 23. 17 and FIG. 16 show a device in which the sensors 3 are fixedly attached to the reference body 4 and touch the side of the body 2 facing away from the compressive force F. Here, too, a stably connected to the bolt 13 resiliently mounted in the reference body 4 presses with one or more balls 41 and is more stable 9

Lever arm 14 the body 2 in the direction of the sensors 3 and causes a bias for this. In contrast to FIG. 16, a body 2 is provided in FIG. 17, which has a groove or opening 18 at its edge. The clamp 12 for holding the body 2 engages in this opening. This has the advantage that the surface 1 projects relatively beyond the plane of the lever arm 14 and the reference body or frame 4. This construction enables the use of an aperture which lies so close to the edge of the body 2 by means of a seal that the device cannot be easily damaged.

FIG. 18 shows a further embodiment of a prestressing element, in which the sensors 3 are fixedly attached to the reference body 4 as in FIG. 17 and touch the side of the body 2 facing away from the compressive force. Unlike there, a leaf spring 19 mounted on the reference body 4 is provided, which presses the body 2 with its free end 20 in the direction of the sensors 3.

19 shows a modification of the embodiment according to FIG. 18, in which the leaf spring is not fastened to the reference body 4 itself, but to a part 21 which can be displaced in the reference body 4 by means of a dovetail-like connection. In this part 21, a screw 22 is rotatably mounted, which is adjustable to change the bias of the leaf spring 19.

21 to 24 show designs with a transparent body (pane) 2, in which various screens 24, 25 are used to cover the sensors 3 and prestressing elements 6. The screens 24 in FIGS. 21 and 22 are so stable that they contribute to preventing vandalism, while the screens 25 in FIGS. 23 and 24 are applied to the edge of the body 2 as a thin, opaque layer. 23, the stable diaphragm 24 is additionally provided. In Fig. 24, the body 2 exceeds the dimensions of the frame 5 and therefore requires a larger area of the thin diaphragm 25. You are thus relieved by the force F. In this case, their attachment is similar to that of the prestressing elements 6 in FIGS. 12 to 15 and 18 to 19. The force sensors themselves would take over the effect of the prestressing force with their property as spring elements with the spring constant kF. 23 and 24 show the possibility of placing the biasing element 6 as a leaf spring on the same side of the body 2 as the force sensor 3. The leaf spring must be firmly connected to the body 2. For this purpose, the leaf spring in the washer 2 is assigned a dowel 35, into which a screw 36 guided through the prestressing element 6 and a spacer sleeve 37 is screwed and thereby firmly connecting the prestressing lever 6 to the washer. Instead of or in addition to the screw connection, it is also possible an adhesive can be used. A seal 33 is arranged between the disc 2 and the frame 4.

20 shows a plan view of the body 4 and the displaceable part 21 with the adjusting screw 22 and two locking screws 23 in order to illustrate the dovetail construction in FIG. 19.

FIG. 25 shows the side view of a locating device in the form of a transparent assembly 26 with a flat screen 27 (display) arranged behind it. In this case, the assembly 26 of the locating device containing the body 2 and the frame 5, as well as the flat screen 27, are connected to the reference body 4 via separate fastening means 28.

FIG. 26 shows the sectional side view of a monitor 29 with an assembly of the locating device in front. The reference body 4 here encloses the monitor as a housing, the front end faces of which hold the fastening elements of the assembly. 11

FIG. 27 shows a front view of another embodiment than the device shown in FIG. 1 with a rectangular body 2 and four sensors arranged in the corners. 27 shows a device with an oval surface 1 of a body 2 and a corresponding oval frame as well as with three sensors and three holding elements.

Depending on the location of the pressure, the pressure-sensitive sensors 3 reproduce electrical data which are evaluated by a processor and are initially used to determine or locate the location on the surface 1 which is touched or pressed by the viewer. If, however, the position is detected, a determination of this position, for example of a symbol shown on the screen 2, can effect the same functional sequence as by clicking on the symbol with the pointer or cursor of the previously known mouse.

12th

Reference list

1 surface

2 bodies (disc)

3 sensor

Reference body

Edge (frame)

Preloading element

feather

Positioning part for sensor 6

Positioning part for prestressing element

10 guide part for body 2

11 edge of the body 2

12 brackets

13 bolts (in 4)

14 lever arm

15 spring

16 internal threads

17 screw 8 opening in the margin of 2

19 Leaf spring 0 Free end of the leaf spring 1 Slidable part in 4 2 Adjustment screw in 21 3 Locking screw 4 Stable cover 5 Thin cover (on body (disc) 2 6 Assembly locating device 7 Flat screen (display) 8 Fasteners 9 Monitor 1 Installation point 2 Installation point 3 Seal 4 Screw for panel 24 5 Dowel 6 Screw for dowel 35 7 Spacer 1 bearing

1 assembly point

Claims

13 patent claims

1. Device for locating pressure forces exerted on a flat or curved, essentially dimensionally stable surface, in which:

a body (2) containing or supporting the surface, preferably a transparent pane, is provided,

- the body (2) is assigned at least three pressure-sensitive sensors (3) distributed over the surface,

the sensors (3) are arranged on a reference body (4), preferably a frame,

Body (2) and reference body (4) are connected to one another by holding elements (6), preferably prestressing elements,

- The holding elements (6) are arranged offset relative to the sensors (3).

2. Device according to claim 1, characterized in that the body (2) is a transparent or opaque disc.

3. Device according to claim 1 or 2, characterized in that the reference body (4) is a frame.

4. Device according to claim 1, 2 or 3, characterized in that the holding elements (6) are resilient and the sensors (3) between the body (2) and reference body (4) hold under tension.

5. Device according to one of claims 1-4, characterized in that the bias is adjustable. 14

6. Device according to one of claims 1-5, characterized in that the body (2) is rectangular.

7. Device according to one of claims 1-5, characterized in that the body (2) is rounded, preferably oval.

8. Device according to one of claims 1-7, characterized in that the sensors (3) and / or the brackets (6) positioning elements (8, 9) are assigned.

9. Device according to one of claims 1-8, characterized in that the body (2) with positioning elements (8, 9) for the sensors and / or holders (6) is provided.

10. Device according to one of claims 1-9, characterized in that the body (2) on its outer edge (11) guide elements (10) are assigned.

11. Device according to one of claims 1-10, characterized in that the one or more sensors (3) are designed as an anchoring element for fastening material.

12. Device according to one of claims 1-11, characterized in that the or the Haiteelemente (6) are designed as anchoring elements for fastening material.

13. The device according to claim 11 or 12, characterized in that the fastening material for connecting the sensors (6) or biasing element (6) with the body (2) or reference body (4) is used. 15

14. Device according to one of claims 1-13, characterized in that the prestressing element (6) comprises a bracket (12) surrounding the edge of the body (2) and one in the reference body (4) perpendicular to the surface (1) of the body (2nd ) arranged bolt (13), which can be moved relative to the reference body (4) against the force of one or more springs (15).

15. The device according to claim 14, characterized in that the bolt (13) is provided with an internal thread (16) and that the spring force is adjustable by means of a screw (17) adjustable therein.

16. The device according to claim 14, characterized in that the bracket (12) and bolt (13) are connected by a lever arm (14), the inner surface of which extends substantially parallel to the surface (1).

17. The device according to claim 14, 15 or 16, characterized in that the sensors (3) are fixedly or resiliently attached to the reference body (4) and touch the side of the body (2) facing away from the compressive force and that one with the in the reference body ( 4) spring-mounted bolt (13) rigid rigid lever arm (14) presses the body (2) towards the sensors (3)

18. Device according to claim 14, 15 or 16, characterized in that the sensors (3) are fixed or resiliently attached to the reference body (4) and touch the side of the body (2) facing away from the compressive force and that a leaf spring mounted on the reference body ( 19) with its free end (20) pushes or pulls the body (2) towards the sensors (3). 16

19. Device according to one of claims 1-18, characterized in that the body (2) is opaque and provided with numbers, symbols and / or letters or can be provided.

20. Device according to one of claims 1-19, characterized in that the body (2) is transparent and the reference body (4) are frame-like.

21. Device according to one of claims 1 - 20, characterized in that the biasing element or elements are also designed as force sensors.

22.Monitor with screen (2) and a device arranged in front of the screen according to claim 20.

23. Monitor according to claim 22, characterized in that the body (2) in the edge region (11) is step-shaped (18).

24. Monitor according to claim 22 or 23, characterized in that the

Body (2) has a recess or opening (18) in the end face of its edge (11).

25. Monitor according to claim 22, characterized in that the surface (1) of the body (2) is associated with an aperture (24, 25), the inner edge of which comprises the visible part of the body (2).

26.Monitor according to claim 25, characterized in that a seal is provided between the inner edge of the diaphragm (25) and the outer edge of the body (2). 17

27. Monitor according to claim 26, characterized in that the body (2) slightly projects beyond the aperture.

28. Monitor according to one of claims 22-27, characterized in that it has a processor and a connection for connecting the processor to the sensors (3) of the device.

29. body (disc) for a monitor according to one of claims 22 - 28, characterized in that it is provided on its end face with mutually opposite recesses (18).