FI81672B - Method and arrangement for indication of direction or angle - Google Patents

Description

METHOD AND APPARATUS FOR INDICATING DIRECTION OR ANGLE ^ 67 2 FÖRFARANDE OCH ANORDNING FÖR ANGIVNING AV RIKTNING ELLER VINKEL

The invention relates to a method and a device for detecting an angle or direction 5, in which the position and direction of movement of a tilt-sensitive vial or similar balancing member are monitored by means of a capacitor arrangement formed of capacitive components placed above or around the balancing member.

10 Known methods of monitoring a gas bubble in a vial include observations by means of a light source and a detector, as well as solutions based on the electrical conductivity of the vial fluid by means of electrodes placed in the vial as the bubble moves within the electrodes. Bubble observations performed by a single light source and detector 15 are disclosed in DE Publication No. 2,636,706, U.S. Patent No. 3,863,067, and Applicant's earlier FI Patent Application No. 841864, which monitor either the bubble interface, transmission, or reflection. The use of two light source-detector pairs is 20 known e.g. U.S. Patent Nos. 4,484,393 and 4,182,046 and Applicant's earlier FI Patent Application No. 870737. Bubble monitoring by means of the electrical conductivity of a vial fluid is known from U.S. Patent No. 4,567,666.

25 The weaknesses of the presented optical bubble observations are the strong thermal drift of the optocomponents, the large variation in sensitivity between different individuals, the individual variation in the extent and symmetry of the light beams, the aging, and the effect of ambient light. Optically observing the bubble in the vial 30 is problematic e.g. due to the abundant interference reflections generated from the inner and outer surfaces of the vial walls. In addition, the shape and size of the bubble tends to vary with temperature and causes calibration and accuracy disturbances.

35 Bubble monitoring methods based on electrical conductivity have to make a special vial to bring the contacts inside the vial, which is expensive and can cause leaks.

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Electrolysis phenomena occur inside the vial and the behavior of the contacts may change.

The method and device according to the invention are able to eliminate the above-mentioned disadvantages and provide a device with which the direction and the necessary change of direction can be accurately detected, regardless of temperature, reflection properties of the bubble in the vial or ambient lighting conditions. To achieve this, the method and the device according to the invention are characterized by what is stated in claims 1 and 4.

Other embodiments of the method and apparatus of the invention are characterized by what is set forth in the appended claims.

The main advantages of the method according to the invention are: - the normal vial is suitable for use and the electrically conductive strips 20 are very easy to fit in the glass or plastic tube of the vial and can be e.g. adhesive films - the capacitance capacitance comparison method does not have problems due to component individuality or aging to an extent than in optical methods

The main advantages of the device according to the invention are: - the small size of the device - no sensitive components are attached to the vial 30 - the device detects and indicates the location of the bubble, even if it is at the extreme end of the vial - the accuracy of the device does not deteriorate

The invention will now be described in more detail with reference to Examples 1A-5a and the accompanying drawings, in which:

Figure 1 shows a labial pair of capacitors formed by metal strips

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Fig. 2 shows a section of the structure according to Fig. 1 and a capacitor principle

Figures 3a and b show a spirit level with a non-conductive liquid and a capacitor principle. Fig. 3c and d show a spirit level with a conductive liquid and a capacitor principle. fixed capacitor arrangements Fig. 7 shows an electrical diagram of a direction or angle indicating device. Fig. 1 shows a vial (4) containing a liquid (6) and a gas bubble (5) around which capacitors are formed from metal strips (1) and (2) and (1) and 3). The so-called there is a spirit level in the air gap (4). The capacitance of capacitors depends on the air gap, its size, the material it contains and especially the properties of the material. There will be a capacitance difference between the capacitor strips (1) and (2) and (1) and (3) if the bubble (5) in the vial deviates from the center position because the dielectric constant of the gas is different from that of the vial liquid. In this case, the kaa-25 family bubble (5) is drifted more into the "air gap" of the second capacitor and, due to the lower dielectric constant of the gas, weakens the capacitance of the capacitor in question.

Fig. 2 shows capacitors formed by metal strips (1) (2) and (3) around the vial (4), and Fig. 2b shows the connection of the resulting capacitors. The movement of the gas bubble (5) in the vial (4) makes the capacitors variable capacitance.

Figure 3a shows the vial (4), the non-conductive liquid (6) and the bubble (5) inside it, and the capacitor plates (1,2,3), all on the same side of the vial, and Figure 3b shows the corresponding electrical connection.

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Figure 3c shows a vial (4) containing an electrically conductive liquid (6a), a bubble (5) and capacitor plates (1,2,3) all on the same side of the vial. Resistors R1 and R2 are formed in the Libel-5 liner and capacitors C1, C2, C3 and C4 are formed. Figure 3d shows a circuit consisting of resistors and capacitors.

Figure 4 shows a spirit level (4) with a gas bubble (5), 10 and a spirit level (6a) which is electrically conductive and metal strips (1, 2 and 3). When the vial fluid is electrically conductive, a capacitor C3 is formed between the metal strip (1) and the vial fluid, and a capacitor C4 between the vial fluid and the metal strip (2) and a capacitor C5 between the vial fluid and the metal-15 strip (3). In addition, the electrical conductivity of the vial fluid will be affected as resistors R1 and R2 in series with capacitors C3, C4 and C3, C5.

Fig. 5 shows an electrical diagram of the metal strip (1) 20 for the strips (2) and (3), which shows together with Fig. 4 how the movement of the gas bubble (5) e.g. at the strip (2) causes an increase in resistance R1, decrease in capacitance C4, resistance R2 decrease and capacitance C5 increase. These have a mutually reinforcing effect, so that even a small movement of the bubble causes a strong conductivity difference between the strips (1) (2) and (1) (3) if a variable voltage is applied to the strip (1). The location of the gas bubble in the region of one of the two metal strips (2) or (3) reduces the capacitance of the capacitor in question, since the second capacitor plate 30 formed by the conductive liquid decreases in area relative to the strips 2 or 3 and increases the series resistance as the bubble displaces the conductive fluid.

Figure 6 shows a type of spirit level (8) suitable for detecting tilting in all 35 directions. A round metal strip (7) is attached to the bottom of the vial and 8 sector-shaped strips (11) (12) (13) (14) (15) (16) (17) (18) are attached to the surface of the vial. The vial contains liquid (9), 5 81 672 and a gas bubble (10). The position of the gas bubble (10) on the upper surface of the vial is monitored, for example, as follows: A voltage of a suitable frequency is applied to the strip (7) and the opposite strips are compared with, e.g., (11) and (15), (12) and (16) The bubble is located mainly in the region of the strip pair that gives the largest signal level difference and the strip pair on the side of the strip that becomes the weaker signal. In this way, the direction of the bubble from the equilibrium state can be easily determined. If two pairs of strips give an equivalent unbalance state to each other, the bubble is in the boundary range of these strips and can be used to print the direction with twice the accuracy of the number of plates.

A preferred embodiment is the attachment of the vial (8) directly to the circuit board (19), to which the strip (7) is connected by a conductor (21) and the circuit board (19) has a pre-etched foil pattern (20) comprising e.g. 8 sector-shaped strips (11) to (18), against which the upper surface of the vial (8) is pressed and fixed in a known manner ·

Figure 7 shows an electrical diagram for applying the invention. The oscillator (22) supplies a square wave to the tilt sensor terminal A1 according to the invention. Through the sensor capacitances / resistances, the signal is distributed to outputs A2 and A3 and further to inputs A and B of the signal reference section (23). The circuit closes through the signal reference section and ground to the oscillator (22). As previously discussed, the position of the bubble in the vial depends on how the signal strengths and -3q resonate on lines A2-A and A3-B. If the signals are equally strong, after the reference and amplifier section (23), the outputs C and D are both logic “1”. Then the output of the NAND 2 port (N2) is a logic “0” and the LED 2 (L2) lights up. that the sensor is in a certain equilibrium position with respect to the ground traction force-35, with a certain accuracy defined in the signal comparison section (23) .When the A signal is stronger than the B signal, the output C is a logic “1” and the output D is “0”. In this case, both inputs of the NAND 1 port (N1) are "1" T-6 81672 and the output is "0", so that LED 1 (LI) is lit. This means tilting the sensor from the equilibrium position to the other direction. When the B signal is stronger than the A signal, LED 3 (L3) lights up under the control of NAND 3 (N3) and indicates the opposite inclination than the previous one.

In particular, it should be noted that the invention has not been limited in any way above, but may be modified within the scope of the inventive idea set forth in the appended claims. Thus, the vial can be shaped flat, whereby the capacitor plates are preferably brought closer to each other and at the same time the shape of the bubble is made low and flat. In addition, any signaling device that produces signals to the human senses, such as audible signals, or combinations of different signaling devices, can act as signaling devices.

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Claims (7)

7 81672 P AENT CLAIMS A method for indicating an angle or direction, wherein the position and direction of movement of a tilt-sensitive vial (4; 8) or a similar balancing member (5; 10) is monitored by an arrangement of capacitors and signaling devices indicate to the user when signals from different capacitors are in equilibrium and the vial (4; 8) is partially or completely placed in the electric field of a capacitor arrangement consisting of at least three capacitor plates (1,2,3) or (7,11,12, .. n), characterized in that when the vial liquid is electrically conductive, the surface of the vial liquid forms said capacitor plates, in which case counter-capacitor plate surfaces, the magnitude of which is controlled by the movement of the bubble and which are connected to each other by means of an electrically conductive liquid and which, when the balancing element (5; 10) is in the desired directional or angular equilibrium position, out of at least two plates (2,3) or (11,12,13, ... n) of substantially equal size. 2. A first preferred embodiment of a circuit according to claim 1 is shown in the form of a plate (1,7) with a capacitor arrangement (1,2, 3 or (7,11,12, .. n) for a signal without an electrical spinning pulse, with a spinning pulse or alternating voltage. Method according to Claim 1, characterized in that the signal applied to the plate (1; 7) of the capacitor arrangement (1,2,3) or (7,11,12, -... n) is an electrical voltage pulse, a voltage pulse train or an alternating voltage. 3. Anordning förfkland förfarandet enligt patentkravet 1, vilken anordning bildas av kondensatorplattor (1,2, 3. eller (7,11,12,13, ... n) monterade i sammanhang account en lutningskänslig libell (4,8) , the oscillator (22) having an electrical signal on the platform (1,7) and an electronic system (23) on the signaling device and the signal device (L1, L2, L3) on the controller and all of the signals or faulty switching devices, the anthem of the Atminstone and the capacitor plate (1,7), with the Atminstone tvA motplattor (2,3) or (11,12,13, .. n) and the same as in the case of the placebo (4.8) och i medelställning av libellens jämnviktorgan (5,10) är för 10 81 672 capacitor plate (1,7) given signal frAn capacitor plate-Tower (2,3) sinsemellan eller condensatorplattorna (11,12,13, ..n) sinsemellan mäsjliga väsentligt with liquid att mottaga. Apparatus for carrying out the method according to claim 1, which apparatus consists of capacitor plates (1,2,3) or (7,11,12,13,. .N) mounted on the sound-sensitive vial (4; 8), on plates (1; 7) an electrical signal oscillator (22) and electronics (23) for processing signals and signaling devices (L1, L2, L3) for checking a certain angle or direction, characterized in that the device comprises at least one capacitor plate (1; 7) with at least two counter plates (2); , 3) or (11,12,13, ... n) and a vial (4; 8) containing an electrically conductive liquid placed substantially in their field and having a β 81672 signal applied to the capacitor plate (1; 7) in the center position of the balancing member (5; 10) from the capacitor plates (2,3) to each other or the capacitor plate East (11,12,13, ... 0) to be received substantially the same size. 4. An arrangement according to claim 3, which comprises a capacitor plate (20). The form and the side of the capacitor board (8) are formed in the form of a capacitor board (19), the capacitor board (8) having a capacitor board attached to the capacitor board. Device according to claim 3, characterized in that the capacitor plates (20) on at least one side of the vial (8) are formed by etching on the circuit board (19), the vial (8) being arranged on said circuit board to rest on said capacitor plates. 5. An arrangement according to claim 3 which comprises a capacitor plate (1,2,3) or a (7,11,12,13,... N) cell according to the genome (4,8) of the genome and for the group of metal parts of the group. Device according to Claim 3, characterized in that one or more capacitor plates (1,2,3) or (7,11,12,13, ... n) are glued to the spirit level (4, * 8) and belong to the group of metal-coated labels. 6. Anordning enligt patentkravet 3 kännetecknad därav, att en eller flera capacitorplattor (1,2,3) eller (7,11,12,13, ... n) är formade pA ytan av Libellen (4,8) i öns- when the genome is shown in the body of the material. Device according to Claim 3, characterized in that one or more capacitor plates (1,2,3) or (7,11,12,13, ... n) are formed on the surface of the vial (4; 8) at a desired location. point with electrically conductive material. Device according to one of Claims 3,5,6, characterized in that the device comprises one or more annular capacitor plates arranged around the vial (4; 8). , 81672 1.Forfarande för att visa en vinkel eller en riktning, i vilket ställningen ell rörelseriktningen av en lutningskänslig li-bell (4,8) ellet av ett motsvarande jämnviktsorgan observeras med hjälp av en anordning, mit bildas av capacitorat och med For the purpose of this signal, the capacitor capacitor is connected to the power supply and the circuit (4,8) or the capacitor and the electrical risk. 7,11,12, .. n) k ä n-netecknat därav, att när 1ibellvätskan är elledan-de, bildar ytan av 1ibellvätskan för sagda capacitorplattor i deras punkt innanför Libellen motsvarande ytorna av konden-satorplattorna, storlekar av vilka libel -thers and, in the case of a genome of which, in the case of a single genome (5,10) and in the case of a single genome, to Plattan (1,7) for signal from Atminstone frAn tvA plattor (2,3) eller (11,12,13, .. n) väsentligt likvärdiga. 7. An arrangement according to the patent of 3,5,6 kännetecknad därav, anordningen omfattar en eller flera ringformiga capacitor plate, which is placerade omkring Libellen (4,8).