RU2390926C2 - Automatic batcher with sensor assembly - Google Patents

Abstract

FIELD: physics.

SUBSTANCE: automatic batcher with an electromechanical drive for batching an article stored in the batcher includes an active sensitive infrared system for detecting a user. The sensitive infrared system includes at least one infrared radiator and at least one infrared receiver. The sensitive infrared system is made with possibility of scanning presence of a possible user at a defined scanning frequency. The sensitive control system provides the active infrared radiator(s) with a first current which is constant during one or more separate scanning cycles, and switches to a second current for further scanning. The first and second currents are determined from signal intensity of the received average infrared radiation which is received by an infrared receiver(s) during a certain number of previous separate scanning cycles. In the simplified system, the average the last received infrared radiation values can be compared with a standard value established in the control system for varying current supplied to the infrared radiator(s).

EFFECT: saving electrical energy.

23 cl, 9 dwg

Description

FIELD OF THE INVENTION

The present invention generally relates to a dispenser comprising an active infrared (IR) system, in particular for dispensers of the type including a dosing system driven by an electric motor, combined with a control circuit for recognizing the presence of a potential user through said infrared sensor system and control the operation of the aforementioned electric motor to dispense the material.

Moreover, the invention relates in particular to an automatic towel dispenser (preferably with paper towels stored inside the dispenser body) of the type with an electric drive, preferably powered by a battery (but which could also be powered by alternating current (AC) or a combination of AC and DC power supplies, in which the IR sensor system is used to control the dosing of products, such as paper sheets (e.g., paper towels for hands), when present a potential / potential user is found to be within a given zone, without physically contacting the user with a dispenser (or sensing elements) required to initiate a dosing sequence.

BACKGROUND OF THE INVENTION

Dispensers of the aforementioned type are known, for example, from US-B1-6695246.

For example, in a dispenser according to US-B1-6695246, the sensitive control circuit uses active infrared radiation (i.e., both emitting infrared radiation and detecting infrared radiation) to control recognition of the presence of a potential user. Infrared radiation is emitted by pulses. In the active IR mode, the presence of an object (that is, a possible user) can be detected within the detection zone from about 12 to 24 cm at the dispenser and, by the said detection, controls the electric motor for dosed dispensing of a hand towel to the user. One IR receiver and one IR emitter are located behind the front cover of the dispenser, and each is installed in the corresponding tube, the tubes are placed adjacent to each other. Through this arrangement, the detection distance is kept small (between about 12 to 24 cm), so that objects that are outside the detection zone do not lead to undesirable and unintended dosing. Similarly, the object must be in the correct position and at the right angle, otherwise the tubes will protect the infrared radiation from being reflected back and collected by the receiver. Thus, while reducing the likelihood of unwanted reflections from other surfaces or the like, the sensor system requires accurate positioning of the hands to carry out the work. When an object is detected, the microprocessor drives the electric motor to dispense the towel if two scan cycles with sufficient reflected infrared radiation are received by the IR control system. In order to drive the electric motor, the system uses a control circuit for the level of background lighting, which provides a reference voltage V _B related to the level of background lighting, and with which the voltage V _{A is} compared with an IR sensor (sensing element). When the voltage V _A is greater than the voltage V _B , the electric motor can act to dispense a hand towel. This provides for automatic compensation of the level of background lighting, so that the signal picked up by the infrared receiver must increase to a higher level in order for the user to be detected.

In the aforementioned dispenser, although a certain degree of compensation is made with respect to background lighting levels that may take into account certain conditions, such a device causes problems due to temporary effects of intense changes in infrared radiation due to atmospheric conditions, in particular when the background infrared radiation is very low because only very small changes in reflected infrared radiation can cause dosing, even when not required.

Similarly, there might also be a problem that as the levels of background IR radiation generally increase to a high level, the user's hand becomes more difficult to distinguish from background IR radiation, since the increased level of IR radiation due to the reflection of infrared radiation from the user's hand, when the hand is in front of the dispenser, can be approximately at the same level as the background infrared radiation, or, due to the temporary blocking of high-level background infrared radiation, the presence of the hand may even lower the level of that of background infrared radiation received in the infrared sensor (sensing element), so that in many cases the hand is not reliably detected.

In addition, the user's hand, which is not detected, or is not correctly located, in a relatively small detection area of the sensitive elements on the dispenser, that is, in a small range of the detected area, and thus, which does not trigger the dispensing of the hand towel immediately, often will be tempted to touch the dispenser to try to force dispensing, in the belief that touching the casing close to the sensing elements is required, contrary to any written notices that e may contain a dispenser in this regard. This, in particular, takes place, since the user's hand is already at the height of the dispenser, as in the aforementioned document. This may result in a lack of hygiene when several users touch the dispenser in sequence.

In addition, while the emitted intensity of infrared radiation from the emitter is apparently constant in the above document (not to mention the possible options for a relatively low battery voltage), such a design, with the hope of battery power from the batteries (preferable than solar cells), often involves the use of excessively high power.

The present invention should, as one of its objectives, propose an improvement in the active detection of infrared radiation to account for changes in the background infrared radiation.

An additional goal is to improve the possibility of better hygiene.

An additional goal is to minimize the power consumption of the device at certain points in time by taking into account the level of background infrared radiation.

Additional objectives of the invention will be apparent from reading this description of the invention.

SUMMARY OF THE INVENTION

The main objective of the invention is achieved by a dispenser having the features defined in paragraph 1 of the claims. Some preferred features of the invention are defined in the dependent claims.

Additional features of the invention will be apparent to the reader of this description of the invention.

The invention provides a means of improving detection reliability by compensating for background levels of infrared radiation of increasing or decreasing intensity by changing the current supplied to the infrared emitter (s), thereby changing the amount of emitted infrared radiation used by the sensitive system. One way of doing this, when the overall levels of background IR radiation are generally high, is that the energy transmitted by the IR emitters is made higher by increasing the current passed through the IR emitter. Thus, a user who approaches the dispenser will be easier to detect in bright conditions, since the amount of reflected infrared radiation, compared with the background infrared radiation, will be greater than if no change in current were made. Therefore, the difference between the received infrared radiation from the reflection from the user's hand compared to the background infrared radiation will be large and, accordingly, the user's hand will be easily detected, which, in particular, is useful when the user's hand is less white, due to the lower received reflection of infrared radiation.

Similarly, in conditions of low background infrared radiation, there is often no need for a strong current in the emitter, since the user's hand will already give a high percentage increase in reflected infrared radiation compared to background infrared radiation for detection. Thus, the current supplied to the emitter (s) can be made lower, which also saves energy. Similarly, when sudden changes in the background IR radiation occur due to sunlight entering the room, or the light being turned on, a lower current in the sensing element means that the relative effect of these changes on the reflected IR radiation (i.e., emitted by the emitter and reflected back to the receiver) compared to the background infrared radiation will be virtually undetected. However, when the user approaches the dispenser in conditions of low background infrared radiation, the increase in reflected infrared radiation received by the infrared receiver will be high compared to background infrared radiation, even at low current levels.

An alternative, possibly simpler method that can be used to change the current of the infrared emitter (s), rather than by comparing (as above) the values of the reflection levels with the background, is to set the so-called "standard value" (threshold value) in the control circuit, which is the value of the expected intensity of the detected signal, which should be received under normal operating conditions. The supplied current could be, for example, 5 mA at this standard value. If this standard value installed in the system is called A1, then during operation the control circuit (its MCU (main control device)) can be configured to calculate the level of infrared radiation, A2, according to a predefined number of the most recently received values IR radiation (that is, a moving average of the most recent values). If A2> A1 (that is, the level A2 of the moving average detected reflection signal is higher than the stored level A1 of the standard signal), for example, as calculated by the MCU, the current supplied to the emitter can decrease, preferably in incremental steps. On the contrary, in the case where A2 <A1, then the current supplied to the emitters can increase, preferably with a certain increment.

The sensing elements in the inventive dispenser are preferably arranged so that the IR emitters create a wide and practical area for detecting infrared radiation, and the infrared detectors (i.e., infrared detectors) are configured to prevent infrared radiation from emitters that directly penetrates into receivers, as well as reduce the reflection of infrared radiation from other directions.

Any locations about the dispenser or sensors, etc., are relative to the dispenser in its normal position of use and are not installed upside down or the like. Thus, the lower part of the dispenser is designed to be at the base. Similarly, the lateral direction of the dispenser is generally in the horizontal direction.

In cases where a vertical direction or plane is mentioned, this is usually intended to indicate a reference to the generally vertical direction. When the dispenser is mounted on a precisely vertical wall (as will be described later, for example, with reference to Fig. 2), the vertical direction, respectively, is exactly the vertical direction. However, if the wall is slightly tilted a few degrees, the vertical direction referred to with the dispenser will also be tilted by the same amount and in the same direction as the wall tilt.

Partly due to the good working area of the sensor system, which can detect potential (possible) users at a sufficient distance from a wide range of normal positions of approach to the dispenser, and thanks to the compensating current that is applied to enable better detection, this allows the system to respond early to the presence of the user and thus allows the dispenser to be designed for low power consumption. This reduced power consumption is possible because, at times when a potential user (that is, an object intended by a user requiring a product to be dosed, such as a piece of hand towel or toilet paper), is not located near the dispenser, the scanning frequency, in addition to low current, supplied to the emitters can also be reduced, without any noticeable risk that the scanning frequency will be too low for a sufficiently quick response when the product must be dosed with detectable by user. When a user is detected, the scanning frequency accordingly changes to a more frequent frequency.

Low power consumption is especially important in dispensers that are fully powered by a battery, rechargeable battery or rechargeable batteries, which are generally designed to work for a long time (for example, enough time to dispense 60 or more rolls of paper without requiring battery replacement), and An improved arrangement of sensors and a touch control system provide the opportunity to use less energy when there are no users requiring a dosage product axis.

The scanning frequency, that is, the number of scanning cycles performed per second, is made to vary according to the location of the user relative to the dispenser, so that the dispenser operates at the first scan frequency (that is, it performs a scan sequence by activating the IR receiver and emitter circuits, and then by emitting scanning pulses in the first number of single scanning cycles, that is, pulses per second) when no possible / potential user is detected. The system then increases the scanning frequency when the user is considered close to the dispenser (that is, penetrated the “first” detection zone). This variable scanning frequency makes it possible to use very low power when no users are close enough to the dispenser, since each scan cycle requires a certain amount of energy, and the number of scan cycles per second can be reduced, and use a higher power level ( more scanning cycles per second), only when required, so that the user experiences a fast reaction time for dispensing the product.

The sensing system of the dispenser can be further improved to reduce energy consumption by providing an additional remote sensing element connected either by a wired connection to the dispenser or by a wireless communication line (for example, IR or radio) with the dispenser. This additional sensing element can be used, for example, to detect a user entering the toilet room in which the dispenser is located, at a different location relative to the entrance, and thus can cause the first scanning frequency to change to the second scanning frequency. Such a “remote” sensing element could, if required, alternatively be mounted on the front facing part of the dispenser and could be configured to operate at a very low scanning frequency, due to the distance of the entrance to the toilet room from the location of the dispenser, so that that time, when a potential user wants to use the dispenser and, accordingly, moved closer to the dispenser, the dispenser was already working at a higher second scanning frequency, provided -governing ability to quickly detect active infrared system of the dispenser defined in the claims.

Alternatively, the same set of active IR-sensitive elements as defined in the claims, which are used to induce the dispenser to dispense the product when a potential user is detected, can also be used to detect the user entering the first detection zone. In this way, a user who is suitable for the dispenser (for example, 40 to 50 cm or maybe even further from the dispenser) will activate the sensor system to change the scanning frequency to a higher scanning frequency and as the user continues to move it / her hands and / or body are closer to the dispenser outlet, the user will be detected as being in the "dispensing zone" and, accordingly, forcing the dispenser to dispense the product (for example, a paper towel for hands or a paper toilet affiliation).

If required, more than two scan frequencies can be used. For example, you can use the first slow scan frequency (such as 1 or 2 times per second), followed by a higher second scan frequency (for example, from 3 to 6 times per second), which are accompanied by an additional higher frequency (for example, from 7 to 12 times per second), due to which, the scanning frequency is changed from one frequency to the next, as the user is detected moving closer to the dispenser. This can be accomplished, for example, by a sequence of different sensitive elements, each of which detects at different distances, with a finite sensor system, such as defined in the attached claims, or, for example, by arranging the same set of sensitive elements to detect increased reflection of IR signal from the user as the user gets closer to the dispenser.

When the user moves away from the dispenser, the scanning frequency, in this case, can again be reduced to a lower frequency, thereby consuming less energy for the sensors.

As will be apparent, even at relatively short distances for the first detection zone (for example, up to about 50 cm from the dispenser, for example, from about 10 ° to about 45 °, or from about 30 ° to about 60 °, to the vertical plane , deflected in the front direction from the back of the dispenser and down), the system has the advantages of significant energy savings, while still allowing a good reaction time for dispensing the towel.

This is because the user suggests that his / her hands should be moved relatively close to the device in order to dispense, and this takes about a quarter and a half seconds at normal hand movement speeds (between 0.2 m / s and 0 , 5 m / s), by that time the dispenser can already be made scanning at the second, higher frequency (or even even higher frequency), and thus capable of dispensing very close to the point in time when the hands are in alleged Research Institute for the dosing (ie, a position where a user might be expected to dispense a towel, typically, public anything from 15 to 25 cm from the outlet of the dispenser).

Similarly, it is advisable that when using the IR sensor system, the sensor system should preferably be able to cope with the exceptional anomalies of short-term reflections of high IR radiation, as they sometimes arise, which could not be fully compensated by the current level currently applied to the emitter, without dosing the towel, so that it is suitable for the perception of two or more consecutive scanning cycles or, for example, a predefined The number of scanning cycles for a number of consecutive scans (e.g. two out of three consecutive scans), each of which occurs at a predetermined level of IR above background level of IR radiation prior to dispensing the product.

Preferential use may consist of a changing scan frequency by setting the first scan frequency, for example, between 0.15 and 0.25 seconds between scan cycles (i.e., the scan frequency when the potential user is outside the first detection zone), or even longer (such between 0.25 seconds and 0.5 seconds), and a second scan frequency, of the order of about 0.08 to 0.12 seconds, between scan cycles, and the requirement of only two consecutive scan cycles (and for example, two of three consecutive scanning cycles), providing a level of reflected infrared radiation above the level of background infrared radiation, to actuate the dosing. Such dosing will be perceived as almost immediate, however, a significant amount of energy used by the sensor system can be saved due to the low initial scanning frequency, which consumes less energy.

Brief Description of the Drawings

The invention will be further explained in more detail with reference to some non-limiting options for its implementation and using the accompanying drawings, in which:

FIG. 1 shows a schematic front view of a paper towel dispenser, showing a schematic view of a first detection zone,

FIG. 2 shows a side view of the arrangement of FIG. 1, according to which the side panel of the dispenser has been removed to show schematic details of a paper roll and a paper transport mechanism,

FIG. 3A is an enlarged cross-sectional view showing the lower part of the casing shown in FIG. 1, also in front and at the location of the infrared sensors,

FIG. 3B is a schematic front view of the arrangement shown in FIG. 3A, showing an approximate front view of the first detection zone achieved by the arrangement of active infrared sensors,

FIG. 4 shows an exemplary plot of the amplitude of the emissivity of the scanning pulses versus time,

FIG. 5 shows a graph of the received signal level versus time for a sequence of received IR reflections resulting from the emitted IR pulses of FIG. four,

FIG. 6 shows a schematic representation of the main elements of a system according to an embodiment of a dispenser according to the invention,

FIG. 7 shows an RC circuit used to make a microprocessor active in the MCU in order to perform a scan cycle, and

FIG. 8 shows an alternative embodiment of the RC circuit depicted in FIG. 7,

FIG. 9 shows an embodiment using an additional sensor element, complementary to the main active sensitive IR system, capable of detecting at a far distance from the dispenser.

Detailed Description of Preferred Embodiments

FIG. 1 and FIG. 2 show dispenser 1 in front and side views, respectively, in accordance with which FIG. 2 shows a dispenser 1 mounted on its rear side to a wall W (fastening means not shown, but may be of any suitable type, such as screws, glue or other fastening means), whereby the back surface of the dispenser lies on said wall W, which usually vertical.

The dispenser 1 contains a housing 2, within which there is a supply of product, in this case, the supply of paper in roll 3. Roll 3, respectively, is a roll of continuous non-perforated paper, but may also contain perforated paper. Also located in the housing 2 is a paper transport mechanism 4, preferably in the form of a modular drive cassette with its own casing 15, which can preferably be removed as a single unit from the housing 2 when the housing is open.

FIG. 1 shows a paper roll 3 and a conveying mechanism 4 that feeds paper from a roll toward an outlet (see below for a further description) as simple blocks for simplicity. Similarly, FIG. 2 shows a paper roll 3 and a transport mechanism 4 in a very simplified form, whereby the transport mechanism includes a drive roller 5 engaged with a support roller 6, whereby a portion of the paper sheet 7 is shown located between said rollers 5, 6, with a leading the edge of the aforementioned paper sheet 7, ready for dispensing, in the outlet 8 formed in the housing 2 on its lower side.

The drive roller 5 is schematically shown connected to a drive motor M powered by batteries B. A gear train, typically in a gearbox, may be included between the drive shaft of the motor and drive roller 5. Suitable batteries may supply 6V when new, and typically four batteries in 1.5 V are suitable for this purpose. Examples of suitable types are the MN1300 Duracell batteries, whereby each battery has a capacity of 13A · h, and which can operate from full to fully discharged in the range from 1.5 to 0.8V. The operation of the electric motor M causes the drive roller 5 to rotate and, therefore, pull the paper sheet 7 from the paper roll 3 by pinching the paper in the contact area of the rollers 5 and 6. When driven, the electric motor rotates, thereby removing the paper sheet from the roll 3, which also rotates in order to allow the paper to move towards the outlet 8. Other types of drive mechanisms for removing paper from the roll may also be used. Details of the paper transport mechanism or other product transport mechanism, however, are not important for understanding the invention. Such devices are also well known in the art per se.

It will also be a priori clear that the drive roller 5 and the support roller 6 can have their functions mutually rearranged, so that the support roller 6 would be a drive roller that is operably connected to the drive motor (and, thus, the drive roller 5 shown on Fig. 2, acts only as a backup roller in contact with the roller 6, usually with paper or a towel in the contact zone between them).

Although the principle of operation is explained using paper in the form of a continuous paper sheet in a roll, it should be clear that the dispenser can be used to dispense other products from the stock of products, for example, such as a continuous piece of paper in the form of an accordion. Alternative products can be dispensed by the device when properly redesigned. It is also possible that other dispensing devices may be connected to the dispenser. For example, the dispenser may further include an air freshener that is activated, for example, every 5 or 10 minutes (or another suitable time) or once after a certain number of dispensed towels. This dispenser equipped with additional elements can be controlled by an element control circuit (to be described later) or a separate control circuit (not described in the materials of this application).

The electric motor M is at rest and without energy supplied to it, when the paper should not be dosed at all. The electric motor M rotates when the paper is to be dosed through the outlet 8. The operation of the electric motor M is controlled by a main control device (not shown in FIGS. 1 and 2, but described later) connected to a sensitive system containing sensitive elements 9-13, of which sensitive elements 10 and 12 are emitters, preferably IR emitters, and sensitive 9, 11 and 13 are IR receivers. Such IR emitters and receivers are well known in the art and typically contain diode structures. Suitable IR emitters and receivers, for example, are manufactured by Lite-ON Electronics Inc., under the type number LTE-3279K for IR emitters and under the type number LTR-323DB for receivers. Other types of IR emitters and receivers, of course, can also be used. In the shown embodiment, the IR emitters 10, 12 and IR receivers 9, 11, 13 are shown distributed at approximately equal intervals continuously in the transverse direction X-X of the housing (generally parallel to the roll 3 of the stock of products). The interval, appropriately, may be an interval of about 5 cm between the next emitter and the receiver, so that the distances between the sensing elements 9 and 10, 10 and 11, 11 and 12, 12 and 13 are all approximately equal.

Emitters and receivers are shown (see FIG. 2) located on the very rear side of the outlet 8. Other arrangements of sensors are also possible, such as all sensors placed on the front facing side of the outlet, preferably in a straight line along the outlet. Alternatively, sensors could be placed on each side of the outlet (for example, emitters on one side and receivers on the other side) and, likewise, extended along the outlet. An outlet, however, could alternatively be located elsewhere. The arrangement of the sensing elements, shown sequentially in the order of the receiver / emitter / receiver ... / emitter / receiver with an appropriate interval, allows the predominant form of the detection zone 14, which is somewhat similar to the language in shape (see Fig. 1, 2 and 3B) . The underlying tongue shape may vary slightly depending on the power supplied to the emitters, and also their degree of protrusion from the surface of their housing, and, moreover, the degree of deepening of the IR receivers, and also according to their interval.

If it is understood from this description that a tongue-shaped detection zone is created due to the interval between the sensing elements, to a small extent, according to the supplied power, and due to the relative positions of the recesses / protrusions of the IR emitters and receivers, the specialist will be able to easily change the shape of the language to meet the specified dispenser needs for any special situation or dispenser size, simply through routine experimentation.

Dispenser 1, upon detection of a possible user (the sequence of detection operations is described further below), without any contact of the user with the dispenser or sensitive elements, for a sufficient time in the first detection zone, thus, forces the dispenser to determine that the user is present in dosing zone and, accordingly, to dose the product. Dosing, in this case, is carried out in relation to the front section of the paper 7, which is automatically released through the outlet 8 (that is, a laterally extending opening in the lower part of the housing, and preferably issuing downward). This allows the user to grab the paper 7 and pull it toward the cutting edge, such as the cutting edge 16 shown in FIG. 2 close to the outlet 8 so as to remove a tattered / cut piece of paper. The location of the cutting edge 16, of course, can be changed, for example, to be at or up to 1 cm lower, and opposite the roller 5.

The first detection zone 14, as shown in FIG. 1, 2 and 3B are shown as tongue-like and tilted down and forward from the outlet at an angle of x °, preferably between 20 ° to 30 ° relative to the vertical axis Y. This is achieved by installing IR emitters and receivers under between 20 ° and 30 ° to the vertical plane, which runs sideways across the dispenser. The angle at which each of the emitters and receivers is inclined can vary up to several degrees, but is usually equal for all emitters and receivers in order to create a better detection zone. The sensor system is thus capable of detecting for the vast majority of its total length, typically between 10 and 60 cm, in the Z direction at an angle of between 10 ° and 45 ° to the vertical plane (i.e., detection in the to some extent the corresponding zone 14 shown in Fig. 2).

Details of one of the preferred arrangements of emitters and receivers with respect to the casing will now be explained with reference to FIG. 3A. The emitters and receivers in this case can appropriately be the Lite-ON emitters and receivers described above.

The lower portion of the dispenser comprises a first cover 50 to which a main PCB (printed circuit board) is attached for the sensing elements 9-13, which are emitters and receivers, as described above. A series of holders 52a and 52b are attached to this PCB to hold each of the sensors. The receiver holders 52a are shorter than the emitter holders 52b in order to provide means for recessing the receivers 9, 11, 13, larger than the emitters, with respect to a flat, flat outer cover 53, which in the case shown is provided with recesses of variable length. The outer cover 53 can be attached to emitters and receivers, for example, by friction fit, if it is decided to attach them as a single unit, although the outer cover 53 can also be attached to the PCB or the first cover 50 where required.

As can be seen in FIG. 3A, each of the recesses in which the emitters and receivers are located is substantially circular. If, for example, conical recesses are provided, the degree of protrusion of the active part of the emitters and the degree of protrusion of the active part of the receivers (that is, for the case in which the receivers actually extend beyond the lower surface 54, as is the case in Fig. 3A, is preferable than being fully in-depth) may require small adaptations to achieve the desired shape of the detection field. The relative protrusion of the emitters and receivers can be observed by comparing the position of the short side dash-dot line on each sensitive element, which line is either below or above the (lower) outer surface 54 of the outer cover 53. In the case of emitters 20, 12, which are made with the possibility of the active radiating part protruding outward from the outer surface 54 to a larger size than the receivers 9, 11 and 13, the line is shown below the outer surface 54 (that is, outside the outer surface 54), then in the case of the active receiving part of the receivers 9, 11, 13, the lines are located above the outer surface 54, since the active receiving part is at least partially recessed beyond the outer surface 54 (it can also be completely deepened, so that it does not have part of it at all, protruding outward beyond the surface 54).

In the case shown, the distance “A” of the tops of the emitters 10, 12 from the surface 54 is approximately 3 mm, and the distance “B” of the tops of each of the receivers 9, 11, 13 from the surface 54 is approximately 1 mm. The distances between the respective sensing elements 9-13 are such that x _{1 is} approximately equal to each of the distances x ₂ , x ₃ and x ₄ . With recessed and protruding dimensions of 1 mm and 3 mm, respectively, a distance of approximately 50 mm for each distance x ₁ , x ₂ , x ₃ and x ₄ was found just suitable.

The magnitude of the recesses and protrusions, as soon as the principles of this invention are understood, can be determined by ordinary experiment. However, a recess may be used so that the IR receivers protrude a distance B between -2 mm (i.e., fully recessed 2 mm) and +1.5 mm, although a small positive distance B between 0.2 mm and 1.5 mm is the most suitable. Similarly, for IR emitters, a protrusion of distance A by 2 to 4 mm can be used.

The a priori protrusion of approximately 3 mm and 1 mm beyond the surface 54, respectively, for emitters and receivers creates a very favorable shape of the detection zone language. The general language shape of the created detection zone 14 is shown in FIG. 3B (which corresponds to the configuration of FIG. 3A) with a dash-dotted line 55 of the perimeter indicating the outer boundary of zone 14. There will be a slight deviation in the shape as well as the total length of the tongue-shaped zone 14 from the outlet 8 in the Z direction (see the Z direction in FIG. 2 ), so that it varies between approximately 25 cm and approximately 50 cm, based on the application of varying power to the emitters, between 0.001 mA s and 0.1 mA s in steady state. The depth of the shown detection zone 14 according to size C of FIG. 2, however, will vary little, even while the extent of zone 14 changes in the Z direction when the power changes. It remains relatively constant for the arrangement of sensitive elements in the example shown, approximately 8 cm.

When the current changes to change the above identification range, it is assumed that a specific identification range is required under steady-state conditions, since the current changes defined in the materials of this application related to the average received infrared radiation, despite this, are not affected to such a large extent by changing the shape detection zone 14, but when compensating for background infrared radiation while maintaining approximately the same size of the detection zone.

In FIG. 3B, the ellipses 56, 57, 58 shown under each of the receivers 9, 11, 13 are smaller than the ellipses 59, 60 shown under each of the emitters 10, 12. This difference in size is due, respectively, to the deepened and protruding essence of these sensors. Ellipses, however, are just a way to schematically represent the principle of the main field of detection and reception, since a practical test of the exact shape of the detection zone shows that it actually corresponds to region 14 bounded by the perimeter line 55. Part of the user penetrating into any part of zone 14 bounded by perimeter 55 can thus be detected by the system.

FIG. 3B also shows that a blind detection gap is formed that extends about 5 cm (with some variation, about 0.5 cm, respectively, varying between 4.5 cm and 5.5 cm), under the bottom surface 54 which surface 54 can be essentially at the same vertical level as the outlet 8. The surface 54, however, can be arranged so that it is 1 to 4 cm above the outlet, however, still providing the outer surface of the dispenser Such that the expected detection field is not blocked in some way part of a dispenser housing.

The blind gap, however, can be made to have a distance of preferably between 4 and 6 cm from the bottom surface 54, depending on the relative protrusion of the emitters and receivers and their transverse interval.

The relatively large size of the blind gap is caused to a large extent by the deepening of almost the entire active part of the receivers beyond the surface 54 (i.e., vertically above the surface 54 in the use position).

The blind gap is also shown in FIG. 1 and 2.

Recessing the receivers 9, 11, 13 (that is, their smaller protrusion outward beyond the surface 54 in comparison with the emitters, or their complete recess, completely above the surface 54) has a particular advantage, since it essentially prevents the emitted infrared signals from lighting directly on all parts of the receivers, which, otherwise, may degrade the reception sensitivity of the system. Moreover, it reduces the interference reflection of infrared radiation from other directions than the detection zone 14.

This, of course, helps to ensure a more reliable identification, which, when combined with the underlying design and features of the invention described in the materials of this application, due to the change in current based on the average background infrared radiation, gives an even better result.

As will be explained in more detail below, when a potential user’s body part enters this first detection zone 14, the sensor system detects the presence of the user and causes the sensor system to change from the first scanning frequency to a second scanning frequency that is higher than the first scanning frequency. The sensor system also causes the motor M to rotate when judged by the user (due to the received signals) as being present in the metering zone.

This arrangement provides the ability to provide a reliable and accurate field for receiving infrared radiation with a shape that is well applicable to the expected positioning of the user's hand when the user's hands are approaching the dispenser.

Although the preferred arrangement of the emitters / receivers, as shown in the figures, has certain advantages, the use of only one emitter and two receivers or more than two emitters and three receivers could also be used. However, preferably, in order to form the desired detection zone, there should be one more receiver than the emitter when they are arranged in series, in the form of a receiver / emitter / receiver, etc. Two receivers (one on each side edge) should preferably be placed close to the outer lateral edges of the sensor arrangement (and thus also the dispenser) in order to provide for the reception of infrared radiation across the width of the widest part of the sensor arrangement in the dispenser, and thus make the dispenser more user friendly ovatelyu by establishing a desired detection zone.

In an alternative embodiment of the invention shown in FIG. 9, an additional sensing element 19, removed from the dispenser housing 2 and, when operating, connected by a wireless or wire connection 20 to the sensing system (schematically shown under 22) and its control system in the dispenser housing, can be used to form the first detection zone 18, which is further dispenser than the detection zone 17 (the detection zone 17 in this case is similar in shape to the first detection zone 14 in FIGS. 1 and 2). Alternatively or additionally, the additional sensing element can be placed on the front of, for example, the front surface of the dispenser housing and facing away from any wall or the like on which the dispenser is mounted to allow a longer detection range in front of the dispenser, such as a sensing element 21 shown schematically, which is also connected to the sensing system 22. The sensing element 19 and / or 21, for example, can be configured to detect the presence of possible users up to a distance greater than the first detection zone, for example, a distance of more than 50 cm, preferably more than 100 cm, more preferably more than 200 cm, and even more preferably more than 300 cm, or even further from the body 2 of the dispenser.

The emitters 10, 12 of the sensor system are arranged using a suitable control circuit that can control the circuit, as is essentially known in the art, to emit pulsed infrared radiation in a narrow frequency band, for example, approximately 15 kHz ± 0.5%. However, a different infrared frequency could be chosen. The receivers 9, 11, 13 are configured to detect the emitted infrared radiation, which is reflected from objects (fixed or moving) back to the receivers. In order to detect infrared radiation, which originates mainly and almost completely from the emitted infrared radiation (even up to very bright conditions of 10,000 lux or more), it is preferable from all sources and frequencies of infrared radiation due to background effects , IR receivers need to tune to the frequency of the emitters. Thus, IR receivers are equipped with a detection circuit that suppresses IR radiation outside the expected frequency range of the reflected waves and amplifies IR radiation at the level of the 15 kHz range. In this regard, although the frequency detection range both above and below the range of the emitted frequency band between 2 kHz and 10 kHz may work in most situations, it may be found more suitable to use the frequency range (frequency band) that lies near 3 kHz or higher, and also below the center frequency of the emitted infrared radiation. Thus, the receivers are tuned (or, in other words, “synchronized”) according to the emitted infrared radiation at a central frequency of 15 kHz, making it possible to detect infrared radiation in the range from 12 to 18 kHz (for example, by using a band pass filter tuned from 12 to 18 kHz). Frequencies outside such a band are thus suppressed to a large extent, while frequencies within the band from 12 to 18 kHz are amplified, with a maximum gain located at a center frequency of about 15 kHz, for example, up to about 53 dB.

By operating with a modulated frequency in the emitters and receivers, exposure to, for example, bright sunlight, which otherwise could cause the saturation of the received infrared signal in comparison with any reflected signal, are essentially eliminated by allowing the device to operate under ambient lighting conditions up to up to approximately 10,000 lux. This ability distinguishes potential users from other background sources of infrared radiation, is also further improved by the ability to supply a varying current to infrared emitters, as disclosed in the materials of this application.

FIG. 4 shows a sequence of individual scan cycles (i.e., emitting infrared pulsed radiation) at a first scan frequency having a time between individual scan cycles t1, a second scan frequency having a time between individual scan cycles t2 that is shorter than t1 (i.e., greater scan frequency than t1), and a third scan frequency having a time between individual scan cycles t3, where t3 is greater than t1 and t2. The time between individual scan cycles is measured as the time between the start of one single scan cycle until the start time of the next separate scan cycle. Each of the individual scan cycles is shown here as having the same pulse intensity (that is, no adjustment is made between the individual scan cycles to account for the previously received reflected scans, which may result in different emissive power supplied to the IR emitters). The additional time t4 is shown, which is a predefined time interval or a predetermined number of pulses separated by time t1 (first scan frequency), which must expire before the system changes the scan frequency to the third, slowest scan frequency with time interval t3. The pulse duration of each individual pulse is usually constant.

The time t1 is set at a constant level to be between 0.15 to 1.0 seconds, preferably 0.15 to 0.4 seconds, that is, from the condition that a separate scanning pulse is separated by an equal time t1. Time t1, however, can vary, and exactly the right frequency to optimize the device for the sake of saving battery power and the reaction time before dosing were found to be around t1 = 0.17 seconds. The second scan frequency is always more frequent than the first scan frequency, and t2 is set to preferably be between 0.05 to 0.2 seconds, preferably between 0.08 and 0.12 seconds, between scan cycles. Time t2, however, may vary to be another suitable value, but is preferably between 30% to 70% t1. The time t3 can be set between approximately 0.3 and 0.6 seconds, although a longer time t3, such as 1 second or even longer, is also possible. However, to start the operating time of the radiating circuit (in particular, by using the starting RC circuit using the RC time constant to cause a current discharge with respect to the microprocessor to initiate the synchronization operation), it is most suitable if t3 is set to double the duration of t1. Thus, t3 can be set to 0.34 seconds in the case where t1 is 0.17 seconds. The initial moment t1 can be made variable, for example, by means of a variable resistor controlled from the outside of the device, although, typically, this can be a factory setting in order to avoid inadvertently changing the time t1, which is inappropriate in certain situations.

The time t4 may typically be selected to be in the order of between 30 seconds to 10 minutes, and may also be adjusted in a variable manner in the device depending on the type of use and the environment that typically occurs where the device should be located. However, a suitable value for optimized operation was found to be approximately 300 seconds, although it can also be large where additional energy is required to be saved.

Although not shown, it will be obvious that additional time periods can also be set in the device with intermediate time periods (i.e., intermediate between T1 values and T2 values, or intermediate between t2 and t3, etc.) or even longer time periods, depending on the operating conditions, although the use of three different scanning frequencies has been shown to take into account most situations with good performance based on reaction time and energy conservation. For example, an additional time period longer than t4, for example, 30 minutes, occurring during the duration of the scan cycles with an interval of t3, could be used to change the time period between the scan cycles to be longer than t3 (e.g. , 10 seconds between individual scan cycles). This situation may be useful when the dispenser cannot be used hard during night time periods. The reason for this will become clearer when studying the following job description.

As can be seen from FIG. 4, after four scanning cycles S1-S4 with a time interval t1, the scanning frequency changes to a second more frequent scanning frequency with an interval t2 and remains at the second scanning frequency for two further scanning cycles S5 and S6. The reason for this change will be explained below with reference to FIG. 5.

FIG. 5 shows an example of a possible level of received signals R1-R7 caused in response to the emission of scanning pulses S1-S7.

The approximate level of background infrared radiation is indicated as the received signal level Q0. This level of Q0, of course, can vary, and, as further shown below, this, however, can be taken into account in several ways. However, for simplicity of explanation, in the following example, in order to explain the basic operation of the sensor system for tuning detection and scanning, it is assumed that Q0 remains substantially constant.

When S1 is emitted and there is no object that is not taken into account in the last background value of the received signal, the background level received at R1 will be approximately at the level of Q0. Similarly, in the next scanning cycle S2, the level of the received infrared radiation is also close to Q0 and therefore does not cause a change in the first scanning frequency. In the scanning cycle S3, the level R3 of the received signal, however, is above the background level, but only to the very minimum degree (for example, less than a predetermined value, for example, less than 10%, higher than the background IR radiation level) and due to This saves the first scan frequency. Such small changes (below a predetermined level) above or below Q0 can occur due to temporary changes in humidity levels or persons moving a greater distance from the dispenser, or spurious IR radiation due to changes in sunlight or temperature conditions around the dispenser.

In the scanning cycle S4, the level of the received signal has reached or exceeded a predetermined value, for example, 10% higher than the background IR radiation, and the sensor system and its control device thus assume that the likely user (for example, hands or the whole body of the user) moves closer to the dispenser in order to remove the product, such as a paper towel. In order to be able to respond faster when it is assumed that the user wants the towel to be dosed (that is, when the level of the received signal has reached or exceeded a predetermined value, for example, 10% higher than the background IR radiation), the scanning frequency accordingly increases to second scanning frequency and, thus, produces the next scan pulse with a shorter time t2 after the previous pulse.

If the signal level R5 received in the next scanning cycle S5 also satisfies the existence criteria at or more than a predetermined level above the background IR radiation (for example, at or more than 10% above the background IR radiation, in accordance with the criteria used for the previous scanning cycles) the sensor system registers through a counter (for example, in memory or another form of register) a single detection above a predetermined level, and then issues an additional scanning cycle S6 with an interval of t2, which to check whether the received IR is still at or above the level of 10% greater than background IR Q0 radiation. As shown in FIG. 5, this is the case for the scanning cycle S6, and the control system of the sensor system (containing both software and a microprocessor, in a preferred form) then immediately outputs an output signal to the motor M to start the rotation of the electric motor in order to dispense the product ( for example, a portion of paper 7 from a roll 3). In this case, that is, when two consecutive scanning cycles are above a predetermined level, the system accordingly determines that the potential user is in the zone, demanding that the product be dosed, and thus determines that the user is in the zone " dosing. "

In the case where only one set of sensing elements is used to detect the presence of the user in the first detection zone (for example, the embodiment of FIGS. 1 and 2), the detection zone and the dosing zone will be the same physical zone, but it is just a touch a control system that logically determines that the user has entered the dosing zone.

However, in the embodiment of FIG. 9, where an additional sensor 9 and / or 21 is used, the signal level R4 will be recognized in zone 18 and, thus, will cause the first scanning frequency to change to the second scanning frequency even before the user has entered zone 17, which, in the case of in FIG. 9 would be a dispensing zone that is different from the first detection zone 18. Zones 17 and 18, of course, could overlap to a lesser or greater extent, but zone 18 in this case always has at least a part of it that is arranged to extend farther from the dispenser than zone 17. In this case, however, for the second scanning frequency is appropriately maintained for a time suitable for the user to physically enter zone 17 (e.g., time to move to the sink, wash hands, and then use a towel). Such a suitable time, for example, can be set between 1 and 10 minutes, during which time the second scanning frequency is maintained, pending the reception of reflected IR signals R that satisfy the criteria by which the product should be dosed.

In an additional situation (not shown), where the level at R5 is lower than a predetermined level (for example, 10% higher than the background IR radiation), the system can be programmed to issue an additional scan cycle and again check whether the level of the received signal is higher than a predetermined level in order to indicate that the user is present and wishes to receive a towel. Thus, it is preferable that the two consecutive scan cycles to require two received signals having a received signal strength above a predetermined level to be generated continuously, it has been found preferable to allow any two or three consecutive scan cycles to be above a predetermined level. Of course, there are also additional possibilities, due to which the number of scan cycles to enable dispensing of the towel would be any two of four consecutive scan cycles, or any three of four consecutive scan cycles, or additional combinations. However, with t1 set to 0.17 seconds and t2 set to 0.1 seconds, it was found appropriate to provide any two of the three consecutive scanning cycles with the ability to start dispensing the product.

In the case shown in FIG. 4, after the towel or other article has been dispensed (released), the system changes the scanning frequency back to the first scanning frequency in order to save energy, and thus, the scanning cycle S7 is emitted at time t1 after the scanning cycle S6. It is clear that this saves energy as timely as possible. However, the second scanning frequency, however, can last longer if required (the situation is not shown in Fig. 4), so that when the user again wants to receive a second or additional product (for example, an additional towel), again moving his hands to the outlet the dispenser opening, again dispensing quickly.

In the case shown in FIG. 5, however, the case corresponding to FIG. 4, where the user, for example, tore off a piece of paper that has been dispensed from the dispenser, and thus the IR radiation level received at R7 is below a predetermined level (for example, a level of 10% or more higher than Q0).

A predetermined level above the background level at which the control system of the sensor system causes the release of the product has been described above as existing 10% above the background for two of three consecutive scanning cycles. However, practical tests have shown that a more suitable level is at or above 12% greater than the background infrared radiation, and even more preferably, at or above 15% greater than the background infrared radiation. This is intended, for example, to take into account the changing lighting conditions that may occur when the user is close to the dispenser, but actually does not want to use it.

However, during the test it was also found that the increase in reflected infrared radiation, which is received, makes it possible to use completely different threshold values in those cases when required. Thus, sensitive circuits, for example, can be adjusted so that a predetermined level above the background level is up to 90% or more, even up to 95% or more, above the background IR radiation, before dosing occurs. This, for example, provides the possibility of a much better discrimination between the reflection from the user's hands compared to any unwanted received infrared radiation with a bandwidth of the frequency spectrum of the pulse from 12 to 18 kHz (for example, in the case of very bright lighting). At the same time, the proximity at which such a high level occurs is usually less than when a predetermined level is used, until the current in the emitters is slightly increased.

In some rare cases, users can move their hands very quickly toward the dispenser and may be annoyed by the need to wait for some time longer than they need the first scan frequency to be replaced by the second scan frequency and wait an additional 0.2 seconds (when using t2 = 0.1), even if it is a short time. An additional manual correction control unit, therefore, can be included in which any single received scan signal at or higher by 30% (or a higher value, such as higher than 95%, in the case described in the previous paragraph) in comparison with a background level can be used to call up immediate dispensing of the product, without requiring successive scanning cycles at or above a predetermined level, even when in the first scan frequency mode. This can also be applied, being made for use in the second scan frequency mode.

After a period of inactivity for an extended time period t4, during which the sensor system was scanning at the first frequency, the system may be allowed to assume that there are no possible users nearby the dispenser. In this case, even the time t1 can be considered too short to allow optimal energy conservation, and thus, the system can change the scanning frequency to a third scanning frequency (lower than the first scanning frequency), during which the scan pulse is issued only once after time t3. However, in this case, when an infrared signal is received that is at or above a predetermined level (for example, 15% or more above the background level), then the system must change the scan frequency directly to a second higher scan frequency, more preferably than first initial first scan frequency. However, in such a case, it is appropriate to require at least two scan cycles, but preferably a larger number of scan cycles, to trigger dispensing of the article. For example, when the toilet room where the dispenser is placed is plunged into darkness, and then, at some point in time, the lamps turn on, the received infrared levels can be taken into account to determine that the user is present. In order to avoid dosing the product in such a case, it may be appropriate to allow the system to have time to account for the levels of background infrared radiation before being able to dose.

In terms of the background level of infrared radiation, as mentioned above, such will vary with time. Similarly, the presence of immovable objects (such as soap dishes, other containers or other immovable objects) within the dispenser area must be taken into account as background IR radiation. In order to do this, it was found appropriate to obtain a moving average of the most recently recorded received IR signals R, in order to continuously change the level of Q0.

For example, four (or more or less than four) of the most recently received infrared signal values can be used to generate the average level of the background signal, for example, by dividing, for example, the sum of the four most recent received signal levels by four. As each new value of infrared radiation is received, the oldest of the four values is removed from the calculation (for example, by removing it from the register or drive of the latest values in the control circuit) and calculating the new average value based on the latest values. The calculation of the moving average and the means required for this, in both hardware and / or software, for the most recently recorded set of values, are very well known in the art of electronics and, therefore, are deemed not to require further explanation.

The predetermined number of previous single scan cycles that are used to form the (moving) average is typically between two and ten scan cycles, preferably between three and six scan cycles, and most preferably, four or five scan cycles. If three or fewer scanning cycles are used to form an average value of the received infrared radiation, and this is used to establish the second current to be supplied to the emitter (s), it may be difficult that the latter values include high infrared values due to the arm temporarily present, and then removed, which causes an artificially high average value of the received infrared radiation. This phenomenon, of course, can be used, if necessary, to give an advantage in setting the current level for the emitter by comparing the set (for example, the last three consecutive scanning cycles) of the accepted values of the infrared radiation, which caused dosing to occur, with the most recent set accepted values of infrared radiation, which did not cause dosing. When four or more scan cycles are used, this gives more stable results for background IR radiation, although using too many values may cause the dispenser to not respond quickly enough to background changes, which, in some cases, may cause the dispenser to respond more slowly to the presence of the user.

By using the moving average level of background infrared radiation, an additional advantage is obtained in which when the user who has just removed a towel or other product holds his / her hands at the dispensing outlet, the level of received infrared radiation will remain high. However, in order to prevent the user from causing the release of a large amount of the product, such as paper towel material, the user's hands will be considered as being background IR radiation when they are relatively stationary, and thus, dosing will not occur. To dispense an additional product (such as paper), the user, therefore, must remove his / her hands from the dispenser sensors in order to allow reading of the “true” background IR radiation (that is, background IR radiation without the user's hands being too close to the device). Only with the renewed movement of the user's hands in the direction of the sensing elements of the dispenser can dosing of the product be called up to occur again.

In addition, another additional means by which misuse of the dispenser can be prevented when the towels are re-removed excessively is to arrange, in addition to or even as an alternative to the above moving average, an adjustable minimum elapsed time between dispensing towels (e.g., time between 2 and 10 seconds). However, this feature is usually not required, since in most cases the inherent expiration time for the system to determine the user as being present in the dispensing zone and to turn the motor to dispense the towel will be sufficient to prevent such misuse.

It will also be appreciated that as the metering batteries discharge over time, the power supplied to the sensing elements may also be affected, which may cause less efficient operation. To prevent this from occurring and, thus, to ensure that a constant voltage is available for supplying the sensing elements (up to a time close to the full discharge of the batteries), a constant current load can be applied. Such constant current loads to ensure voltage stability are well known per se in this field of electronics and, therefore, are considered not to require additional description, although it may be understood that their use in a sensor circuit for such a dispenser as described in the materials of the present application is particularly useful. The amount of additional energy required to control the constant current load is negligible, and, accordingly, the use of such a device is barely noticeable in a usable battery life.

The power supplied to the emitters can additionally be configured to vary by automatic control, respectively, between a value of 0.001 to 0.1 mA · s (using a 6V battery assembly) in order to take into account the received intensity of the reflected signal from previous cycles scans, in particular those that result in dosing, as compared to those that did not cause dosing (i.e., a later presentation of unchanged background IR radiation), and that adjust the level of emitted infrared radiation to a more appropriate level.

This can be achieved by changing the current in the emitters, for example, between 1 and 100 mA (that is, the possibility of a 100-fold change). This can be done by using a PWM (Pulse Width Modulator, PWM) module 106 (which will be described later), whereby a rectangular PWM signal is converted to a direct current (DC) voltage having an output power proportional to the PWM duty cycle, and in why the MCU changes the PWM duty cycle to regulate the DC voltage in the emitter circuits and, accordingly, the power of the emitted IR signal based on the input signal intensity received by the sensors and sent ny in the MCU. For example, if the intensity of the reflected signal is very low in the last few scanning cycles (for example, five scanning cycles) when dosing occurred, this may be because the typical brightness of the user's hands is low and the background lighting levels are relatively high. This can cause the levels of the received signal to be only slightly higher than the predetermined level compared to the background infrared radiation, until the user's hands are located very close to the sensitive elements, which can lead to difficulty in detection in some conditions. In this case, it may be appropriate to increase the power supplied to the IR emitters in order to receive a more easily perceptible change in the signal, that is, the first current rises to the second higher current, and this second current is applied during the next pulse (or pulses) scanning that will be sent (until an additional change in the background IR radiation is detected, which can lead to an additional change in the current sent to the emitter (s)).

Similarly, if the typical brightness of the user's hands is high and the background IR levels are low, it may be appropriate to lower the power supplied to the IR emitters, while an easily perceived change in signal level is received (i.e., the level of reflected IR radiation during dosing time compared to the level of background infrared radiation). In this way, the power supplied to the emitters, in addition, is further optimized to take such conditions into account while ensuring reliable and fast recognition and dosing. Thus, in addition to very high light conditions, only very low power can be used with respect to sensitive elements. Thus, it will also be understood that the dispenser can be optimized so that the first detection zone, in which the presence of a possible user causes a change from the first to the second scanning frequency, is selected between approximately 20 and 60 cm, preferably between 25 cm and 50 cm from the outlet. It will be obvious that additional power increases with respect to the emitters will increase the detection range, but power consumption will increase to a much greater extent, and false detection can also occur more often. A range of up to 50 cm from the dispenser to enable user detection is the preferred maximum for most assemblies.

When changing the current level from the first to the second current, however, it may be appropriate to design a control circuit so that the first and second current levels are kept constant, for example, for at least one second (or even longer) before being allowed to change to another current level.

By varying the supply current to the emitters in the aforementioned manner, the power supplied to the emitters is optimized to take into account background conditions in order to ensure reliable and fast recognition and metering without using excessive battery energy.

An alternative, possibly simpler method that can be used to change the current of the infrared emitter, rather than by comparing (as above) the values of the reflected infrared radiation with a common background, is to set the so-called "standard value" or “Threshold value” in the control circuit, which is the value of the expected intensity of the detected signal received under normal operating conditions. The supplied current can be, for example, 5 mA. If this standard value is called A1, then during operation, the control circuit (its MCU) can calculate the level of infrared radiation, A2, according to a predetermined number of the most recent received values of infrared radiation (that is, a moving average of the latest values) . If A2> A1 (that is, the level A2 of the moving average detected reflection signal is higher than the stored standard signal level A1), the current supplied to the emitter can decrease, preferably in incremental steps. On the contrary, in the case where A2 <A1, then the current supplied to the emitters can increase, preferably with a certain increment.

For each single scan cycle, the current supplied to the emitter should normally be kept substantially constant. Thus, for both the first current level and the second current level, the current is kept substantially constant at such a corresponding current level. In addition, as it will be clear, there are not only two possible current levels, since as soon as the second current level is sent in one single scan cycle, such a second current level becomes the first current level for the next scan, and the second current level will be the next current level which must be set (with increase or decrease, or unchanged in each scan cycle), all depending on the results of the most recent moving average received infrared radiation.

The average value of the received infrared radiation is calculated from a predefined number of previous single scan cycles. Preferably, a predetermined number of previous single scan cycles refers to scan cycles that immediately precede the most recent scan cycle. A suitable predetermined number of scan cycles may be between 2 and 10 scan cycles, preferably between three and six scan cycles, and most preferably four or five scan cycles. To calculate the average received IR radiation, the last (for example, four) single scan cycles are used, and the average value of all input signals of the IR receiver is used for each scan cycle. In the next average infrared radiation that is calculated, the last four single scan cycles are immediately last used, then they are used again (the oldest scan cycle from previous scan cycles has now been removed from the calculation).

An additional method of measuring the background infrared radiation is preferable to taking the average of the previously received infrared values, which include the received infrared reflection values from the emitted infrared radiation, in order to perform a reception scanning cycle (i.e. , actuate the receiving circuit for a small amount of time with the emitters turned off) and measure the level of incoming infrared radiation. This may be accomplished, for example, by means of an MCU. The average value of a predetermined number of previous single reception scan cycles, which, in this case, are used to form the average value of the received infrared radiation (with the emitter out of operation) as already described.

In the case of using disconnected emitters to establish the background infrared radiation, it may also be appropriate to fix the level of received infrared radiation (especially in cases where the residual energy of the batteries is very low, so that the current levels supplied to the emitters should not or cannot continue increase), which is, for example, approximately 90% of the received value of the infrared radiation by the infrared receiver when the infrared emitter is turned off. Other values could be selected, for example, 85% and higher. Deviations of infrared radiation at this absolute level of received infrared radiation are often too small for the unmistakable ability to distinguish between changes in the received infrared radiation caused by the presence of the user compared to external influences, and this can lead to inappropriate dosing. This situation is most likely to occur in dispensers where pulsed infrared radiation with a limited frequency is not used (that is, in contrast to the aforementioned radiation system with an a priori limited frequency of 15 kHz and the detection of 12-18 kHz described above), due to a significant degree more low absolute levels of background infrared radiation, which are required to saturate the sensor reception system.

It will also be understood that the dispenser can be optimized so that the outermost edge of the first detection zone, in which the presence of a possible user causes switching from the first to the second scanning frequency, is selected between approximately 20 and 60 cm, preferably between 25 cm and 50 cm from the outlet. An additional increase in power in the emitters to achieve a greater range will increase the detection range, but power consumption will increase to a much greater extent, and false detections can also occur more easily despite the additional measurement of the emitter's power level.

In a further preferred embodiment, the dispenser may be configured to have two modes of operation, one that is an identification mode (or a “user identification” mode) described previously, by virtue of which active perception of infrared radiation is effective, the other mode being the mode of “hanging” towels, for example, by virtue of which, every time a paper towel is dosed and, moreover, removed (for example, torn off), a new paper towel is released from the dispenser. For this purpose, for example, a cutting edge 16, as shown in FIG. 2, could be set so that the application of pressure on the cutting edge (often referred to as a cutting mechanism) causes the switch to be actuated to start the electric motor M to dispense a new piece of towel ready to be torn off. The device may also include a manual switch, so that this “hanging” towels can be manually set by the user or automatically set by a timer, for example, with known time periods when the dispenser will normally be in constant use, and the use of an active IR sensor system is temporary redundant.

The “hanging” mode of a towel, for example, can also be suitable in conditions of excessively high background infrared radiation (for example, above 5000, and preferably above 10000 lux), when the sensor infrared system is completely saturated and, therefore, cannot detect the difference in increased level of infrared radiation from the user compared to background levels, despite any switching from the first current to the second current supplied to the emitters. The dispenser is thus configured to detect the level of infrared radiation with respect to the threshold value (i.e., the maximum threshold value), and when said threshold value is reached, the touch control system (i.e., the control system for the touch system) switches the mode dispensing the dispenser from the user identification mode (that is, comparing the received infrared radiation with the background infrared radiation to actuate the dispensing, as described previously) to the toweling mode, in which a piece of paper sheet towel is pulled out of the outlet and remains hanging there until it is removed, after which an additional paper towel is pulled out of the outlet 8 and remains hanging there again.

However, the detection of the average value of the received infrared radiation, preferably, is still calculated over the time that the towel hanging mode is in operation, and the control system is configured to switch the mode back from the towel hanging mode to the dispensing mode when the average the value of the received infrared radiation falls below a threshold value.

Immediate switching back may not always be suitable, since the average infrared radiation could only drop temporarily below the threshold value, and the device would constantly switch between hanging and user recognition modes, which could confuse the user. Thus, it may be preferable to include a time delay of the first predetermined period of time (for example, five seconds or more, or even longer time periods) before switching back to user authentication mode.

Even further improvement can be achieved by executing software (or, optionally, hardware) of the control system with the ability to prevent switching back to said user identification mode during said first predetermined time period if the average value of the received infrared radiation for such a time is higher maximum threshold value of infrared radiation. In addition, this helps to further smooth out the effects of temporary changes in the background infrared radiation.

In a dispenser using emitted pulsed infrared radiation (for example, at an AC voltage of 15 kHz, as explained above), the level of background infrared radiation, caused in particular by light (containing all frequencies of infrared radiation), which requires such a transition In the “hanging” mode, towels will normally be at a very high level (for example, up to or more than 10,000 lux). However, switching the mode from the user identification mode to the “hanging” mode of the towel is especially useful in an inexpensive type of dispenser system where the IR radiation is not pulsed, but a wide frequency band of the IR radiation is simply emitted and a wide frequency band is received. In such cases, the saturation level of the receiving side of the sensor system occurs at much lower lighting levels (for example, about 1000 lux). Thus, switching from a user identification mode to a towel hanging mode could offer a useful addition to such devices without incurring the cost of limited pulsed frequency emission and special amplifiers and filters on the receiver side.

An additional circumstance by which it may be useful to switch to the “hanging” mode of the towel takes place at a time close to the full discharge of the battery, when the power consumption of the active sensor IR system is inappropriately high for the remaining battery energy (when it relates to normal use, which delivered the device). In this case, low battery power can be used to automatically switch (through the dispenser control system, which includes a sensor system) to the mode of "hanging" towels and turning off the emitters used for the recognition mode. Alternatively, the device may be equipped with a low battery warning indicator, which could be used by the operator to put the manual switch in the towel hanging mode until the batteries are replaced.

FIG. 6 shows a block diagram of a basic system according to one embodiment of a dispenser according to the invention, in which the part shown by the dashed line includes the main components for modulating the infrared signal, emitting infrared radiation and receiving infrared radiation used to transmit the identification signal to (analog / digital) A / D modulation of the main control unit (MCU), which device contains a microprocessor.

Rectangle 101 and 102 denotes infrared emitter (s) and receiver (s), respectively, generally corresponding to the previously described emitters 10, 12 and receivers 9, 11, 13 described above. These IR emitters and receivers are preferably photodiodes. The hand shown outside the dashed lines indicates that the infrared radiation emitted by the emitter (s) 101 is reflected by the hand back to the receiver (s) 102. The node 103 is a photoelectric converter for converting the received infrared signal before it is transmitted to filtering and amplification unit 104, where the pass-bandpass filter and amplification circuits act to amplify the received signal near the center frequency in a limited bandwidth and, thereby, to proportionally suppress other frequencies of infrared radiation. The signal is then passed to the signal rectifier 105 because the IR signal is an AC signal. From node 105, the signal passes to the A / D module of the MCU.

The output of the PWM module 106 is controlled by the MCU so that the square-wave signal from the PWM can have its own duty cycle variable by the MCU to control the DC voltage in the emitter circuits and, thus, the power of the emitted IR signal. The PWM 106 is connected to the D / A converter 107 and to the node 109 of the excitation circuit of the infrared emitter, which includes a constant current load mentioned earlier. The same excitation circuit of the IR emitters also provides a signal from the phase-detection module 108, which provides a 15 kHz (0.5%) pulse modulated signal (or another modulated signal frequency that is considered appropriate) so as to excite the emitters 101 through emitter driving circuit 109 for emitting modulated IR signals for short intervals (for example, each signal is emitted for approximately 1 ms). In this regard, it should be noted that before the modulated signal is emitted, the MCU, first of all, must already put into operation the node 104 of the filter and gain circuits for the received signal for a short period, for example 2.5 ms, before emitting a modulated pulse, s in order to allow the receiver circuit to stabilize in order to reliably detect reflected IR radiation from the emitted IR signal. Since the assembly 104 is already in operation when the infrared scan pulse is emitted, and since the filters and the amplification assembly are centered on the center frequency of the emitted pulse, there is no need to synchronize the timing of the emitted pulse and the received pulse to any additional degree.

The signal from the node 109 delivers the information to the on / off control unit 110 of the IR emitter. The MCU I / O module 118 also supplies a signal to the node 110 to turn on and off, as necessary, thereby performing a scan cycle of infrared radiation through the emitter 101.

In order to drive the microprocessor (that is, put it in an active state to perform a scan cycle at a certain frequency), the launch RC circuit 115 supplies a signal to the MCU, to the transition detection unit 114 to the active state. Node 117 is an external interrupt detection node.

From I / O module 118, there is a transfer to node 119, which can be considered as a motor control circuit, which drives motor M when the sensor system (which preferably includes MCUs and software) has detected that the product must be dosed due to the determination the presence of the user in the dosing zone.

Additional peripheral nodes 111, 112, respectively, are a paper recognition circuit assembly and a low power detection circuit (that is, for detecting batteries close to full charge). The node 116 indicates the battery power that is used to drive the MCU, as well as all other external devices and the electric motor. The assembly 120 may be a motor overload circuit that cuts off power to the motor, for example, when paper becomes jammed in the dispenser or when there is no paper in the dispenser. Node 121 is a paper length control unit that operates so that a constant paper length (which, by itself, is adjustable in a variable manner by manual operation, for example, with a variable resistor or the like), each time the motor is made to operate dispensing a certain length of the paper sheet 7 through the outlet 8. This assembly 121 may also include a low power compensation module, whereby the electric motor is rotated at low power for a longer period of time in order to dispense an identical length of the paper sheet, although the assembly may simply be a pulsed position control system whereby the rotation of the electric motor is counted by a sequence of pulses and the rotation is stopped only when the exact number of pulses is reached. Such a pulsed position control system, for example, could include a rigidly located photo interrupter that can detect gaps in a corresponding split unit attached to the drive shaft of the electric motor (or, alternatively, on the drive roller 5, operably connected to the drive electric motor) . The assembly 122 may be an insufficient paper detection circuit, and the assembly 123 may be the assembly used to indicate whether the housing is open or closed. This, for example, can be used to automatically feed the first portion of paper from the paper roll through the outlet when the housing is closed, for example, after refilling with a new roll of paper, so that the person refilling the dispenser is sure that the device is dispensing properly after of how it was closed.

Although not shown here, a sequence of warning or status lights may be associated, for example, with various nodes, such as nodes 111, 112, 120 to 123, to indicate specific conditions to a potential user, or to a person servicing the dispenser or a repair worker (e.g. if the batcher electric motor is jammed or the batcher needs to be re-filled with paper, or the like).

FIG. 7 shows one embodiment of an RC control circuit that can be used to provide a synchronized microprocessor active state transfer in an MCU. The principle of such a circuit is widely known and, in the present case, a suitable value for the Re resistor is 820 kOhm, and for a capacitor - 0.33 microfarads. Although not specifically shown in FIG. 6, the active state RC circuit uses the MCU I / O 118 to provide the synchronized active state function of the microprocessor, so that a scan cycle occurs at a prescribed time interval (for example, t1, t2 or t3). When there is a drop from high to low voltage at the input / output, as a result of the RC circuit, the MCU will “go into active state” and perform a scan cycle. This transition to an active state leading to a scan cycle also requires software support. Similarly, the length of time t1 and / or, t2 and / or t3 can be appropriately performed as a multiple of the time constant of the RC circuit, whereby the input signal from the RC circuit can be used in software to determine whether or not a cycle is required scanning in each interval. In this regard, it will be noted that the RC circuit undergoes changes in the input voltage (via VDD, which is the MCU power supply obtained after passing through the diode from the battery voltage source). As the voltage of the battery (or batteries) drops, there will be an increase in the RC time constant in the circuit of FIG. 7, and thus the time intervals t1, t2, and t3 set initially will change as the batteries become more depleted. For example, with a time interval t1 set at a predetermined level of 0.17 seconds for a battery level of 6 V, dropping to a full discharge level of 4.2 V will increase the time interval t1 to 0.22 s. Thus, the values of t1, t2, t3, etc., as used in the materials of this application should be understood as being values when the battery source is completely discharged.

FIG. 8 shows a modified RC circuit that has the advantage of using less current than the circuit shown in FIG. 7. In FIG. 8 three bipolar transistors are used to minimize the current used when the MCU is inactive.

Under normal conditions, the digital circuitry inside the MCU operates in a high voltage logic state and a low voltage logic state in which the load current is very low. However, when the RS state transition circuit is connected, as in FIG. 7 (by virtue of which the indication “to the MCU” implies attaching an MCU to the input / output port), this creates an abrupt change in voltage at the MCU I / O port, which is a proportionally increasing abrupt change in voltage due to the charge and discharge process in the RC circuit . This creates a relatively long period of operation for the digital circuit in the MCU, which in turn results in an internally higher power consumption in the internal circuits of the IC (integrated circuit, IC) than is present during normal operating conditions. This results in somewhat higher power consumption for the MCU during its “shutdown” cycle (that is, the MCU “idle” cycle).

According to the circuit of FIG. 8, the modification includes the use of two input / output ports of PAU (on the right side of the figure) and PB7 (on the left side of the figure) of the MCU. An important aspect of this circuit is that two transistors Q2 and Q3 have been added to the cascade, which together modify the characteristics of the RC discharge. The output of the PA7 MCU, in this case, gives a steeper discharge curve. The delay time constant for transferring the MCU to the active state is determined according to R4 and C1, which were set to 820 kΩ and 0.68 μF, respectively, in the example shown. Of course, other values for other time constants can be selected.

A quick, abrupt change in voltage at port PA7 is achieved after conversion to Q2 and Q3, which minimizes the time required to switch from a high voltage logic level to a low voltage logic level. Such a circuit as in FIG. 8 can achieve a power reduction of about 40% during an idle cycle compared to circuits of circuit 7 for approximately the same RC time constants. Thus, the RC synchronization circuit of FIG. 8 is especially useful when maximum energy is to be saved.

Claims (23)

1. A dispenser for automatically dispensing an article stored in an article stock of said dispenser, said dispenser comprising an electric, preferably battery, power source and an active IR sensor system, said IR sensor system including at least one IR emitter and at least at least one IR receiver, wherein said IR sensor system is configured to scan for the presence of a possible user at least at the first scanning frequency, and a sensor control system is provided so that said active IR emitter is supplied with a first current that is substantially constant during one or more single scanning cycles, but which can be changed to another, second substantially constant current for additional scanning, said first and the second currents are determined based on the signal intensity of the average value of the received infrared radiation, which is received by the aforementioned at least one infrared receiver during the preliminary about a certain number of previous single scanning cycles, wherein said dispenser is a paper towel dispenser, wherein the sensor control system is configured to detect a maximum threshold value of the average received infrared radiation, by which said sensitive control system switches the dispensing mode of said dispenser from user recognition mode to towel hanging mode. 2. The dispenser according to claim 1, wherein said sensor control system switches said dispensing mode from said towel hanging mode to said user identification mode when the average value of the received infrared radiation is measured below said maximum threshold value. 3. The dispenser according to claim 2, in which said control system is configured with a time delay so that when the average value of the received infrared radiation is measured below the maximum threshold value, said switching operation from said towel hanging mode to said user recognition mode delayed by at least a first predetermined time. 4. The dispenser according to claim 3, wherein said first predetermined time is at least five seconds. 5. The dispenser according to claim 3, wherein said control system is configured to prevent switching to said user identification mode if said maximum threshold value is exceeded within the first predetermined time. 6. The dispenser according to claim 2 in which the average value of the received infrared radiation is measured using each turned off infrared emitter. 7. The dispenser according to claim 6, in which the sensor control system is arranged so that when the average value of the received IR radiation with each IR emitter turned off is above 90% of the average value of the received IR radiation with each IR emitter turned on, said user authentication mode was disabled. 8. The dispenser according to claim 7, in which said control system switches to a towel hanging mode after disabling the user identification mode. 9. The dispenser according to claim 7, in which the control system switches from said mode of hanging the towel back to said user identification mode upon detecting that the average value of the received IR radiation with each turned off IR emitter is at or below 90% of the average value received IR radiation with each IR emitter turned on. 10. The dispenser according to claim 1, wherein said second current is made higher than said first current when the average value of infrared radiation received by said infrared receiver rises from a first average value of received infrared radiation to a second higher average value of received Infrared radiation, and becomes lower than said first current when the average value of infrared radiation received by said infrared receiver decreases from a first average value of received infrared radiation to a second lower average value of received AND radiation. 11. The dispenser according to claim 1, in which the first standard value A1 was set in the control circuit corresponding to the value of the expected intensity of the detected signal received under normal operating conditions, and in which the control system is configured to calculate the moving average value A2 from a predetermined amount the most recent accepted values of infrared radiation, in this case, when A2> A1, the current supplied to the radiator is preferably reduced in increments, and in the case where A2 <A1, the current aemy in radiators is increased preferably at the increment steps. 12. The dispenser according to claim 1, wherein said predetermined number of previous single scan cycles is between two and ten scan cycles, preferably between three and ten scan cycles, and most preferably is four or five scan cycles. 13. The dispenser according to claim 1, wherein said first current and said second current can vary within fixed maximum and minimum limits. 14. The dispenser of claim 13, wherein the maximum limit is between 10 and 150 greater than said minimum limit, preferably between 50 and 120 more, and more preferably between 95 and 105 more. 15. A dispenser according to any one of claims 1 to 14, wherein said sensor system can also scan at a second scanning frequency, said second scanning frequency being higher than said first scanning frequency, and in which the sensor system is configured to change said scanning frequency from said first scanning frequency to said second scanning frequency by receiving a reflected infrared radiation level greater than a predetermined value above the background level of IR radiation during the first predetermined number of single scanning cycles, and in which the sensor system causes the product to be dosed by said dispenser when said sensor system detects a change in the received IR signal intensity that is at or greater than a predetermined intensity level The IR signal is above the background intensity level of the IR signal during a second predetermined number of single scan cycles. 16. The dispenser of claim 15, wherein said predetermined signal intensity level is at or above 10% higher than the background level, preferably at or above 12% higher than the background level, and more preferably at or above 15% higher than the background level . 17. A dispenser according to any one of claims 1 to 14, wherein said sensor system comprises a plurality of IR receivers and at least one IR emitter, preferably at least one IR receiver more than the number of IR emitters, and when this value from the values of the received infrared radiation at all receivers is used to form a single average value of the received infrared radiation during one single scan cycle. 18. The dispenser according to claim 17, wherein said sensor system comprises at least two infrared emitters and at least three infrared receivers, each emitter having one receiver on each side thereof, provided that the emitters and receivers are in the order receiver-emitter-receiver-emitter-receiver in the lateral direction across the dispenser, and the interval between each emitter and each adjacent side of the receiver is essentially equal. 19. A dispenser according to any one of claims 1 to 14, wherein said dispenser comprises an outlet at or close to its lower surface, and each of said emitters and receivers is arranged on said lower surface. 20. The dispenser according to claim 1, wherein said dispenser is a paper towel dispenser configured to store a stock of paper and dispense at least a portion of said stock of paper. 21. The dispenser according to claim 19, wherein said IR emitters are controlled by a sensor control system to bring the IR radiation to such a level that the detection field provided by said emitters is capable of detecting the presence of a potential user at a distance of up to 25 cm from said exhaust openings, preferably up to 50 cm from said outlet. 22. A dispenser according to any one of claims 1 to 14, wherein said sensor system is configured to emit infrared radiation with only a first emission frequency band, and wherein said sensitive system is configured to detect radiation in a limited detection frequency range, wherein said first emission frequency is preferably about 15 kHz, and said detection frequency range is preferably a range between about 12 kHz and about 18 kHz. 23. The dispenser according to one of claims 1 to 14, in which a constant current load is used to supply direct current to each IR emitter.

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