ES2267941T5 - DISPENSER WITH MEANS OF GROUNDING AND ITS METHOD. - Google Patents

Abstract

A grounding mechanism and method for grounding a dispenser are provided, consisting in having an internal low-impedance path (2016) for electrostatic charges that build up during use of the dispenser. The electrostatic charges are discharged to a local ground to which the low-impedance path is connected.

Description

Dispenser with grounding means and its method.

Field of the Invention

This invention is related to the field of paper roll dispensers. In particular, it is related with a carousel dispensing system for paper towels, adapted to dispense paper from a plurality of rolls. This Invention is related to the field of proximity sensors. In particular, it is related to the field of sensors phase balance proximity.

Background

As you can easily see, a problem long-standing existing is to keep towels available paper in a dispenser and at the same time use each roll of the most complete way possible to avoid wasting paper. As part of this system, the person who replenish the towel dispenser. An optimal solution would do the most easy as possible and as "foolproof" as possible the operation of the towel replacement system, and would function in such a way that the smallest amount possible of wasted paper towels. This waste could take the form of "residual" rolls of paper towels not used

The transfer devices are used in some roll towel dispensers as a means of reducing waste and reduce operating costs. These Transfer devices work in a variety of ways. The most efficient of these devices starts automatically feeding on a reserve roll once the initial roll it's over. These devices eliminate waste originated by a maintenance person when replacing rolls small for new rolls, striving to prevent the Dispenser run out of paper. However, these devices Transfer tend to be difficult to load and / or work. Consequently, these transfer devices are used less frequently, although they are still present.

The current mechanisms of bars transfer tend to require the maintenance of a person to remove any unwanted tube (or tubes) from the core, remove the initial partial roll from the position of reserve, and place the initial partial roll in position now residual roll vacancy. This procedure is relatively long and difficult, partly because the roll positions residual in these current paper towel dispensers tend to get stuck and are hard to catch.

In order to keep a roll available in the dispenser, it is necessary to provide the replacement before The roll is over. This factor generally requires making a "replenishment" before the end of the current roll of towels of paper. If the person who replenishes the dispenser arrives too much late, the roll of paper towels will be over. If the replenishment takes place too early, the amount of towels of paper in the almost finished roll, the "residual" roll, will be wasted unless there is a method and mechanism to end the residual roll, even when the dispenser has been filled. There is another problem, as to the ease with which it is added A new replacement roll to the paper towel dispenser. He goal is to bring the new spare roll "on the fly" when the last towel of the residual roll is used. If it's a task easily done by the person who replenishes the dispensers, there will be a greater probability of being used really the paper towel of the residual roll and also that it put a spare roll into service before the roll residual is completely over. It would be extremely desirable to have a paper towel dispenser that tends to minimize wasted paper working in a close way to "dumb test" regarding replacement and use Complete of the residual roll.

How to improve and further develop a system to deliver paper towels to the end user in a way profitable and in a way as friendly as possible, it is desirable an automatic means to dispense paper towels, making unnecessary for the user to physically touch a command or a lever.

It has been known for a long time that the insertion of an object with a dielectric constant in one volume with an electrostatic field, it will tend to modify the properties that Look at the electrostatic field. For example, sometimes warns that placing a hand near some radios changes The tuning of the radio. In these cases, the ownership of the hand, a dielectric constant close to that of water is enough to alter the net capacitance of a tuned circuit within the radio, where that circuit affects the tuning of the signal from RF that is being demodulated by that radio. In 1973, Riechmann (U.S. Patent No. 3,743,865) described a circuit which used two antenna structures to detect an intrusion in an effective space of the antennas. Frequency and amplitude of a relaxation oscillator were affected by affecting the value of your sync capacitor.

Capacity (C) is defined as the load (Q) stored in separate conductors with a voltage difference (V) between drivers:

C = Q / V

For two infinite conductor planes with a charge per unit area of sig, a separation d, with a dielectric constant ε of the material between the infinite conductors, the capacitance of a surface A is given
by:

C = ε A \ sigma / d

Therefore, where a part of the material of separation has a dielectric constant ε1 and another part of the material has a dielectric constant \ varepsilon_ {2}, the net capacity is:

C = \ varepsilon_ {1} A_ {1} \ sigma / d + \ varepsilon_ {2} A_ {2} \ sigma / d

The human body is 70% water. The constant Water dielectric is 7.18 x 10-10 farads / meter, in comparison with the dielectric constant of the air (STP): 8.85 x 10-12 farads / meter. The dielectric constant of water is more 80 times the dielectric constant of the air. When putting a hand in a part of a space between the plates of a capacitor, which occupy, for example, one hundredth of a detection region between large, but finite parallel conductive plates, a desirable detection capacity, in terms of changing capacity, is around is 10-4. It contributes with around 10 -2 with the difference of the constants dielectric and with about 10 -2 with the difference of "surface".

In addition to that of Riechmann (1973), they have used, or could be used, other circuits for the proximity detection.

An important aspect of a detector circuit of proximity of this type is that it is cost effective, reliable and easy to manufacture. A circuit made with few pieces tends to help the reliability, cost and ease of manufacturing. Other desirable feature for electronic circuits of this type is that they have a high degree of noise immunity, that is, They work well where there is electromagnetic noise and interference. He Circuit works better in more places. It will have a functioning Acceptable in more areas of application.

US 4,831,488 discloses a device to eliminate electrostatic charge in electrostatic printers,  subjecting the paper to a potential difference by means of a high alternating voltage The paper is fed through two electrodes, where one of the electrodes is fed with the high alternating voltage, while the other electrode is maintained at chassis ground potential with respect to high voltage alternate Such a device needs a high alternating voltage and two electrodes However, in many places where a paper towel dispenser, there is no access, or there is no convenient access to a cable or ground pipe of a system 110 V or 220 V power supply or ground bars or to another grounding conductor.

One form of the invention is a method for ground a dispenser to a local land, according to the claim 1.

Preferably, the method further includes the step of connecting a tip roller to a towel dispenser paper to a ground wire. More preferably, the method includes the step of using a spring contact to connect said shaft from tip roller to said ground wire.

In another form, the invention is a mechanism of grounding for a paper towel dispenser, according with claim 4.

Preferably, the dispenser is a paper towel dispenser, and the ground wire is arranged to connect to the axis of a dispenser tip roller.

The spring contact can be arranged to connect to a compression spring of a tip roller which is arranged to make contact with a tip roller metal.

The invention may also be a dispenser. with any of the grounding mechanisms mentioned above, such as a paper dispenser according to the claim 11.

Summary of the invention

The invention comprises a system of dispensing based on a carousel for paper towels, in particular, that acts minimizing the real waste of paper towels. The invention comprises means for holding and position at least a first and second roll of paper, one with with respect to the other, means for dispensing paper from the first roll, means for dispensing paper from the first roll and from the second roll simultaneously, when the first roll is reduced to a predetermined paper diameter, means for positioning the first roll sold out for replacement without removing the second roll, and means for dispensing from the second roll and from the replacement roll simultaneously, when the second Roll is reduced to a predetermined paper diameter.

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The embodiment of the proximity sensor it comprises a circuit according to the principle of a balanced bridge, where detection is based on detecting a phase difference, which depends on the amount of capacitance difference detected or capacitance change in a detection region.

A second embodiment of this invention It comprises a second electronic proximity sensor. The second detector circuit is a miniaturized proximity sensor, with a micro-power, capacitance based, designed to detect the approach of a hand to the towel dispenser. Its characteristics are stable operation and a selector of sensitivity of three positions.

A third embodiment of this invention it comprises a method, an apparatus and a system for grounding the static electricity generated in the towel dispensers of paper, to a local high impedance electrical ground. This invention uses a high conductivity path to interconnect any internal component subject to electricity generation static This internal earth of high conductivity and low impedance leads to an electromechanical contact outside the dispenser. A metallic contact between the high path conductivity and, for example, the wall against which it is mounted The dispenser provides an electromechanical contact for the dissipation of static electricity generated in the dispenser, by means of a high impedance local electrical ground, such as Wall.

An aspect of the invention is a method for ground a dispenser in a local land, which includes the Steps of: Provide a low impedance internal path for static electrical charges that accumulate during the use of the dispenser; and connect the low impedance path to a contactor ready to make contact with a grounded surface when the dispenser is mounted. Static electric charges are discharge to a local land through the surface set to land.

Preferably, the low impedance path It consists of a ground wire, and the method also includes the step of connecting to the shaft of a dispenser tip roller to the ground wire. More preferably, the method also includes the step of using a spring contact to connect the shaft of the tip roller to the ground wire.

According to claims 1 and 4, the Contactor is a metal spring in contact with the wall.

Another aspect of the invention is a mechanism of grounding for a dispenser. The setting mechanism land includes: a means to provide a low internal road impedance for static electrical charges that accumulate during use of the dispenser; and a means to connect the road low impedance to a contactor arranged so that it does contact with a grounded surface when mounting the dispenser. Static electric charges are discharged at a local land through the grounded surface. He Grounding mechanism may include: a ground wire of low impedance; a spring contact connected to the cable land and ready to connect to a place of accumulation of static electricity in the dispenser; and a metal clamp of grounding spring in contact with the wall, connected to the ground wire and ready to make contact, by the pressure of the spring, to a wall making electrical contact with a ground local. Preferably, the ground wire is arranged to connect to the axis of a dispenser tip roller. Plus preferably, the spring contact is arranged to connect to a compression spring of the tip roller, which is arranged to make contact with a tip roller metal.

Another aspect of the invention is a dispenser. which includes the grounding mechanism mentioned above. He dispenser may include: a first support adapted to hold a first roll of paper; a second support adapted to hold a second roll of paper; a third rigidly connected support to the first and second supports and rotating around an axis; and one transfer bar by means of which the role of the second Roll can be dispensed together with the paper of the first roll. Such dispenser can also include a detector adapted to shoot the paper dispensing from the dispenser, when the A user's hand within the field of a sensor.

Brief description of the drawings

The features will now be described. Preferred of the present invention, by way of example only, with reference to the accompanying drawings, in which:

Figure 1 is a side elevation of the dispenser with the lid closed, the mechanisms not being visible internal;

Figure 2 is a perspective view of the dispenser with the lid closed, the mechanisms not being visible internal;

Figure 3 shows a view of the support of the carousel, interlocking bar and transfer bar;

Figure 4A is a perspective view of the dispenser with carousel and transfer bar fully loaded with a main roll and a residual roll;

Figure 4B is a side view of the bar interlocking showing the placement of the springs of compression;

Figure 4C shows the mechanism of interlocking in which the interlocking bar closest to the back of the housing is adapted to be installed in a attachable structure in the back housing;

Figure 5 is an exploded view in carousel set perspective;

Figure 6A is a side elevation view of the paper that is fed from the residual roll while the tail of the main roll is located below the bar transfer;

Figure 6B is a side elevation view of the waste roll completely depleted, so that the bar transfer introduces the tail of the main roll into the mechanism of feeding;

Figure 7A is a side elevation view of the carousel, ready to be loaded when the main roll reaches a specific diameter;

Figure 7B is a side elevational view of the interlocking bar being pushed forward to allow the carousel to rotate 180º, placing the main roll in the previous position of the residual roll;

Figure 7C shows the extension springs which tend to keep the legs of the transfer bar in contact with the residual roll;

Figure 7D shows the cleanable floor of the dispenser;

Figure 8A shows a circuit diagram of proximity;

Figure 8B (prior art) shows the LM393 dual comparator scheme from National Semiconductor;

Figure 9A shows the square wave output in U1A, pin 1;

Figure 9B shows the waveforms RC exponentials on pin 5;

Figure 9C shows the waveforms RC exponentials on pin 6;

Figure 10 shows an outline of a second proximity switch;

Figure 10A shows the asymmetric oscillator and the first static protection circuit;

Figure 10B shows the antenna, the circuit of antenna replacement, a second static protection circuit, the follower circuit of the intermediate storage unit of the antenna and peak detector circuit; and a detector circuit of peaks;

Figure 10C shows the low pass filter to reject 50/60 Hz, the amplifier circuit and the points of test to adjust VR1 to 3.0 V, with all external loads that they act as capacitance in the relevant place;

Figure 10D shows the capacitor of self-compensation, the rejection capacitor of the 50/60 Hz and the output comparator that will produce a pulse of output for signals that have passed all rejection tests; These tests are designed to prevent spurious signals start an output pulse;

Figure 10E shows a switch and a sensitivity selection circuit;

Figure 11A is a perspective view of a paper towel dispenser with an access hole for the ground wire, and shows a molded rib that prevents the low impedance ground wire make contact with a wheel crazy teeth;

Figure 11B is a perspective view of a screw hub and molded ribs to join the clamp ground spring in contact with the wall to the chassis of the dispenser;

Figure 11C is another perspective view of the screw and rib bushing to connect the spring clamp ground in contact with the wall to the chassis;

Figure 12A is a perspective view of the gear cover with a molded rib that holds the contact spring in place;

Figure 12B is a perspective view of the ground wire making contact with the spring clamp and entering in an access hole towards its other end;

Figure 12C is a side elevation view of the Towel dispenser showing the ground wire, the contact of spring that connects to the ground wire and also connects to the earth spring clamp in contact with the wall;

Figure 13 is a perspective view of the ground wire path, once it enters the hole of access;

Figure 14A is a perspective view from behind the opening for the spring contact pliers in contact with the wall of the towel dispenser;

Figure 14B is a perspective view of the ground spring clamp in contact with the wall in place, in the back of the towel dispensing unit of paper;

Figure 15 is a perspective view of the flow path of static charges including from the roller tips to the axis of the tip roller, the compression spring, the spring contact and ground wire; Y

Figure 16 is an elevation view showing The compression spring.

Detailed description of preferred embodiments

The following description is the best mode currently contemplated for carrying out the invention. This description should not be taken in a limiting sense, but is done merely for the purpose of describing the principles General of the invention. The scope of the invention must be determined with reference to the claims.

An embodiment of the invention comprises a carousel-based dispensing system with a bar transfer for paper towels, which acts by minimizing the Real waste of paper towels. How improvement and development additional system to deliver paper towels to the user end in a profitable way and in a way as friendly as possible, an automatic means for dispensing towels from paper, making it unnecessary for the user to physically touch a control or a lever. An electronic proximity sensor is included as part of the paper towel dispenser. A person can approach the paper towel dispenser, extend your hand, and make the proximity sensor detect the presence of the hand. The embodiment of the invention shown here is a system that advantageously uses a minimum number of pieces both for the mechanical structure as for the electronic unit. Have, therefore, improved reliability and maintenance, contributing both to profitability.

An embodiment of the invention comprises a carousel-based dispensing system with a bar transfer for paper towels, which acts by minimizing the Real waste of paper towels. Transfer bar coupled with the carousel system it is easy to load by one service person; consequently, it will tend to be used, allowing the residual rolls to be used completely. In summary, the carousel / transfer bar assembly comprises two components, a carousel set and a bar transfer. The carousel spins an exhausted residual roll to a position where it can easily be replaced by a full roll At the same time, the previous main roll that has been used until its diameter is less than certain centimeters p, where p is a rational number, is rotated towards down to the residual roll position. The new roll's tail main in the upper position is introduced under the part of "bar" of the transfer bar. When the residual roll runs out, the transfer bar moves down by spring action, until the tail of the main roll is hooked between the feed roller and the tip roller. The carousel assembly is symmetric about an axis horizontal. An interlocking bar is removed to unlock the carousel assembly and allow it to rotate around its axis, and then released under the action of the spring to interlock again the carousel assembly in place.

A side view, figure 1, of the dispenser 20 with the lid 22 in place, it shows a circular bulge top 24, which provides room for a full roll of towels of paper installed in the upper position of the carousel. The shape of the dispenser is such that the front cover is tucked inwards in bottom direction to provide lower volume of the dispenser at the bottom, where there is a residual roll Smaller paper towels. The form tends to minimize the global size of the dispenser. Figure 2 shows a view in perspective of the dispenser 20 with the lid 22 in place and the circular (cylindrical) bulge 24, together with recess 26 in elevation over the lid 22, which tends to visually guide a hand towards the false button 28, leading to the activation of a proximity sensor (not shown). A emitting diode of light (LED) 130 centrally on the false button 28. LED 130 (Figure 3) serves as an indicator that the dispenser 20 is activated and dispensing a towel. LED 130 may be off while the dispenser is not dispensing. Alternatively, LED 130 may be on (activated), and when the dispenser 20 is running, the LED 130 can emit a blink LED 130 may appear green when the dispenser 20 is ready to dispense and in flashing green or orange when the dispenser 20 is working to dispense. May Use any similar combination. The lowest consumption of Power takes place when LED 130 turns on only during a dispensing work cycle. The recess 26 in elevation (figure 2) allows you to bring a hand closer to the sensor of proximity (not illustrated).

Figure 3 shows the main elements of the carousel set 30. The arms 32 of the carousel have about reduced friction pivots 34 for rotating rolls of paper towels, which are arranged in the recesses of the rolls of paper towels (66, 68, figure 4A). Bar 36 of interlocking serves to interlock and release the carousel so that rotate around its axis 38. The interlocking bar 36 is dependent on one of the corresponding bars 40. The two Corresponding bars 40 serve as support bars. The cross members 42 serve as stiffeners for assembly 30 of carousel, and also serve as guides to extract the paper and drive it down to feed roller 50 and out of 20 dispenser. These crossed members are joined in a way rigid with the corresponding bars 40 and, in this mode of realization, do not turn.

The legs 46 of the transfer bar 44 do not they rest against the pivots 34 of reduced friction for the Rotating rolls of paper towels when a residual roll 68, but are arranged inwardly of the pivots 34 of the rolls. Part 88 of bar 44 of transfer will rest against a structure of the dispenser, by for example, the upper part of the electronic modular unit 132, when a residual roll 68 is not present. Part 88 of the bar 44 transfer acts by carrying the tail of a new roll main of paper towels 68 (figure 4A) down to the roller 50 supply, which includes intermediate bushings 146 (figure 3) and a shaft 144. The carousel assembly is arranged inside the fixed housing 48. The cover is not shown.

The feed roller 50 serves to feed the paper towels 66, 68 (figure 4A) which are dispensed on the curved ribs 52 dispensing. The curved ribs 52 dispensed are curved and have a lower contact area with the paper towel dispensed (no illustrated). If the dispenser 20 gets wet, the curved ribs 46 dispensing help dispense the paper towel to be be dispensed by providing a small friction and maintaining the towel dispensed away from wet surfaces to which I would play in another case.

The feed roller 50 is typically as wide as the paper roll and includes rollers 142 of transmission and intermediate bushings 146 on shaft 144 of transmission. Work drive rollers or bushings 142 of transmission (Figure 3) typically have a width of one inch (2.54 cm) or less, with intermediate bushings 146 (figure 3) located between them. Intermediate bushings 146 are slightly smaller in diameter than the drive rollers or bushings 142 of transmission, and have a diameter of 0.038 cm to 0.114 cm less than the transmission rollers or transmission bushings 142. In this embodiment, the diameter of the intermediate bushings 146 is 0.076 cm less than the transmission roller 142. This configuration  of transmission rollers or transmission bushings 142 and bushings intermediate 146, tends to prevent the paper towel dispensed it wrinkles when it passes through the transmission mechanism and reduces friction, requiring less energy to operate the feed roller 50.

A control unit 54 operates a motor 56. The batteries 58 supply the power to the motor 56. The motor 56 may be located near batteries 58. It may incorporating a light 60, for example a light emitting diode (LED), in a low battery warning, so that the light 60 is turns on when the battery voltage is below one level predetermined.

The lid 22 of the dispenser is preferably transparent, so that the amount of Main roll used (see below), and also so that you can easily see the low battery light 60. In another case, it would be necessary to provide an individual window on a cover opaque 22 to see the low battery light 60. Another solution could be driving the light through a fiber optic light tube to the transparent window on the lid 22.

In a waterproof version of the dispenser, a thin piece of foam rubber cord is disposed within a U-shaped groove of the mating surfaces between edge and groove of the cover 22 of the housing 48. The tray dispenser 62 is a modular component that is removable from the dispenser 20. In the waterproof version of dispenser 20, the dispensing tray 62 with molded rotating ribs is retired When removing the modular component, the tray dispenser 62, water is less likely to be diverted to the dispenser 20, by the dispensing tray 62, acting as a funnel or ramp if a water pipe or sprinkler is directed to the 20 dispenser by the tray and wet the paper towel. The towel  of paper is dispensed straight down. A more likely need of a waterproof version of the dispenser takes place there where the dispenser is located in an area subject to cleaning by half hoses The dispenser 20 has a switch on-off that goes into a state of deactivation when lid 22 is turned down. The switch real is located on the underside of module 54 and is not illustrated.

In one embodiment, the user can run the paper towel dispenser by placing a hand in the sensitivity field of the dispenser. There may be some Adjustable delay durations between sensor activations.

There is another aspect of the presence of water on the dispenser 20 or near it. It will be described later in more detail a proximity sensor (not visible), including details of its operation. However, as can be seen, the sensor detects capacitance changes such as caused by the introduction of an object with a constant high dielectric with respect to air, such as water, as well as a hand that is water in about 70%. A on-off switch 140, which can be deactivated before directing the hose down and It can be activated manually later. The switch 140 can also work in a way that activates itself again after a period of time, automatically. The switch 140 can operate in both modes, according to the mode or modes chosen by the user

An independent switch 64 of activation-deactivation "jumping", so that a maintenance person can adjust the paper towel 66 by pressing a jump switch 64 loaded by a spring, which provides a temporary movement of the roller 50 of feeding.

Figure 4A shows the dispensing box 48 with the carousel assembly 30 and the transfer bar 44. He Carousel set 30 is fully loaded with a roll main 66 and a residual roll 68, both mounted on the arms 32 of the carousel and which can rotate on pivots 34 of reduced friction for rotating rolls of paper towels (only illustrated from the back of arms 32 of the carousel). In the carousel assembly 30, the two arms 32 of the carousel, joined by the corresponding bars 40 and members crossed 42, rotate as a carousel around a horizontal axis defined by the rotation pins 38 of the carousel assembly. The interlocking bar 36 is supported, or is transported, by the corresponding bar 40. The corresponding bar 40 provides structural rigidity and support. The interlocking bar 36 It serves primarily as an interlocking mechanism. Each one of the rolls 66, 68 of paper towels have an inner tube of cardboard that acts as a central winding element, and that provides a hole at each end of roll 66, 68 of towels to fit the pivots 34.

Figure 5 shows the carousel assembly 30 in an exploded perspective view. The number of pieces that Understand this set is small. From the point of view of the reliability, said reliability increases. From the point of view of manufacturing, manufacturing ease increases with it and it Reduce manufacturing cost. The manufacturing material is not limited but for the cost requirements, ease of manufacturing, reliability, strength and other requirements imposed by manufacturer or demand.

When the main roll 66 (figure 4A) and the residual roll 68 (Figure 4A) is in place, arms 32 of the Carousel are connected by these rolls 66 and 68 (Figure 4A). To the place crossed members 42 to connect arms 32 of the carousel with interlocking 36 and the corresponding bar 40, it results in better structural stability, preventing shear deformation. Bar 36 of interlocking, which had been illustrated as a bar 36 of single unit interlocking in the previous figures, acts as an interlocking bar 36 for locking the assembly 30 of Carousel in proper orientation. It also acts as a bar release which, when released, allows to rotate the assembly 30 of carousel. Two compression springs 70, 72 are used to center the interlocking bar 36.

Figure 4B is a side view of the bar interlocking illustrating the placement of compression springs. Compression springs 70, 72 also tend to oppose the release of interlocking bar 36, ensuring that it requires a force required to unlock the bar 36 of interlocking The force required is typically between 0.226 kg-force and 1,359 kg-force, or more. In this embodiment the force is 0.9 kg-force when the spring is in a position fully compressed and 0.498 kg-force when the  Spring is in rest position. In the resting position, the Opposing spring forces compensate each other.

The actual interlocking occurs as illustrated in Figure 4C. The interlocking bar 36 closest to the part back of the housing 48 is adapted to fit in a attachable structure 118 in general U-shape, which is adapted to hold the interlocking bar 36 and prevent it and the 30 set of carousel that rotate. When bar 36 is pulled from interlocking from the back of the housing 48, the bar 36 interlocking is disengaged from the docking structure 118. The attachable structure has a "high" 120 upper side and a lower "low" side 122, where the lower side has a "ramp" 124 on its lower side. As you pull the interlocking bar 36 to free the high side 120, the carousel assembly 30 is free to rotate, so that the upper part of the carousel assembly 30 rotates upwards moving away from the back of the housing 48. As the Carousel set 30 starts to spin, the user releases the interlocking bar 36 which, under the influence of springs of compression 70, 72 placed symmetrically, returns to its position of repose. As the carousel assembly rotates, the end of the interlocking symmetric bar 36, which was arranged originally towards the user, turn now and make contact with the ramp 124. A spring, for example 70 or 72, of the bar interlocking, is compressed as the end of the bar 36 of interlocking in contact with ramp 124 now moves up ramp 124. The end of the interlocking bar 36 is pressed into the space between the lower side 122 and the side upper 120, when the end of the interlocking bar 36 is slides past the bottom side 122. A nailed position for carousel assembly 30.

Figure 5 shows the arms 32 of the carousel adapted to receive the load of a new roll of towels 66 (figure 4A). The arms 32 are slightly flexible and are folded out in a small amount when a roll 66 of paper towels (figure 4A) between two opposite arms 32 of the carousel. A reduced friction pivot 34 is inserted to the rotating rolls of paper towels in a hole of a roll 66 of paper towels (figure 4A), such that a pivot 34 for rolls is inserted into a hole on each side of the roll 66 of paper towels (figure 4A). It is also illustrated in the figure 5 fasteners 74 resistant to handling, joining the reduced friction pivots 34 for rotating rolls 34 of paper towels to arms 32 of the carousel.

Figure 5 shows the surface 76 of the pivots 34 of the rolls and the surface 78 of the arms 66 of the Carousel, they are in mutual contact. These surfaces 76, 78 of contact can be made of a more frictionless material that of which the arms 32 of the carousel are made and the pivots 34 for the rolls. For example, a plastic such as polytetrafluoroethylene (PTFE), for example TEFLON, as a thin layer on each of the surfaces of Contact. The paper towel dispenser 20 and its components they can be made, although not limited to them, of plastic, metal, an organic material that can include, but not limited to them, wood, cardboard, treated or untreated, a combination of these materials and other materials for batteries, paint, if any, and waterproof material.

Figure 6A shows the paper 80 feeding from the residual roll 68, while the tail 82 of the roll main 66 is located below bar 44 of transfer. The legs (leg 46 visible and the other not illustrated leg) of the transfer bar 44 rest on the roll residual. When the diameter of the residual roll 68 is greater in certain number of turns of paper towels than the inner roll 84, the legs 46 of the transfer bar 44 have the bar 88 of transfer bar 44 so that it rotates upwards from the feed roller 50.

Figure 6B shows the situation in which the residual roll 68 is depleted, so that the bar 44 of transfer introduces the tail 82 of the main roll 66 in the feed mechanism 86. Figure 6B shows the position of the residual roll 68 empty, since the residual roll has been finished. The core 84 of the residual roll is still in place. When the roll residual 68 is finished, the legs 46 of the bar 44 of transfer move core 84 of the residual roll up (inner roll), and transfer bar 88 is left arranged down towards the feed roller 50 and towards the top of a structural unit of the dispenser 20 (figure 2), for example the upper part of the electronic module 132 (figure 3). Initially the main roll 66 is in reserve, and its tail 82 is in an "idle" position, so that it is under transfer bar 44. The main roll 66 and its queue 82 are not initially in a "transmission" position. However, as the residual roll 68 runs out, the downward movement of transfer bar 44 driven by the load of its spring, carries the bar 88 of the bar 44 of transfer down to hook the tail 82 of the roll Main with feed roller 50.

Figure 7A shows the carousel assembly 30 ready to load when main roll 66 reaches a specific diameter The diameter of the main roll 66 can be measured by comparison of that diameter with form 122 of widened "ear" (figure 4A) at each end of the arms 32 of the carousel. That part of each arm 32 of the carousel is made to measure a critical diameter of a main roll 66. The set  Carousel 30 leans forward when locked. He carousel set 30 can turn unattended once it releases the interlocking bar 36, due to the heavy nature upper roll upper. That is, the torque produced by the gravitational thrust of main roll 66 is greater than necessary to overcome friction and the antagonistic pair produced by the residual roll 68 now empty.

Figure 7B shows the charging process in the that the service person pulls the interlocking bar 36 and allows the carousel to rotate 180º, placing the main roll 66 in the previous position of the residual roll 68. Now you can put a new full size roll 66 in the position of the main roll 66. Transfer bar 44 is restored automatically by itself. The transfer bar 44 is loaded by the spring so that it is arranged with the legs 46 of the transfer bar pressed up against the residual roll 68 or against core 84 of the residual roll. The 46 legs of the transfer bar are adapted to fit arranged within the pivots 34 of the rolls, so that the bar 88 of transfer bar 44 will have an effective stop over a more rigid place, in this case, the upper part of the electronic module 132 (figure 2).

Figure 7C shows springs 126, 128 of extension, which tend to hold the legs 46 of the bar transfer in contact with residual roll 68 or core 84 of the residual roll. The transfer bar 44 contains the two Springs 126, 128 extension. The forces of the springs are typically from 0.022 kg-force to 0.226 kg-force in the lowered position of bar 4 and from 0.09 kg-force to 0.453 kg-force in the raised position of the bar 44. In this embodiment, the spring forces are 0.09 kg-force in the down position and 0.194 kg-force in the elevated position The strength of the two springs 126, 128 is additive,  so that the transfer bar 44 is subjected to a total spring force of 0.181 kg-force in the down position and 0.399 kg-force in the elevated position

Although the modular units (figure 7D), such such as the electronic module 132, the engine module 56, and the case 150 battery are removable, fit or "fit pressure "together, so that the top of the electronic module 132, the top of the engine module 56 and the remaining elements of the "floor" 148 of the unit 20 dispenser form a flat and easy to clean surface. Dust and paper waste tend to accumulate in the floor 148 of the dispenser 20. It is important that the dispenser 20 have the ability to be easily cleaned as part of maintenance procedure A quick wipe with a cloth Wet will sweep and collect any unwanted buildup. The 64 modular removable dispensing tray can be removed for the Rinsing or cleaning.

The feed roller 50 can be driven by a motor 56 which, in turn, can be driven by a  battery or batteries 58, or be operated from a 100 or 220 socket AC V, or be operated from a transformer which in turn is connected to an AC circuit. The batteries may be no rechargeable or rechargeable. Rechargeable batteries may include, although not limited to it, lithium ion, metal hydride, metal-air, not metal-air. The Rechargeable batteries can be recharged, not limited to it, by electromagnetic induction of AC, or by light energy using photocells.

A feed roller 50 serves to feed the paper towel that is being dispensed on curved ribs 52 dispensing. A gear train (no visible) can be placed under housing 86 (figure 3), to drive the feed roller. A unit 54 can be used control (figure 3) for a motor 56 (figure 3). To activate or deactivating the motor 56 can serve a proximity sensor (no illustrated) or a hand operated switch 64.

How to improve and further develop the system to dispense paper towels to the user in a cost-effective manner and as friendly as possible, an automatic means for dispense paper, making it unnecessary for the user to have to physically touch a knob or a lever. Therefore, a more hygienic dispenser. The dispenser will contribute to a minor transfer of matter, whether dirt or bacteria, from a user To the next one. The results of washing your hands will be preserved and hygiene will increase.

A proximity sensor is included as part of the paper towel dispenser. A person can approach the paper towel dispenser, extend his hand, and have the proximity sensor detect the presence of the hand. When the hand is detected, an engine that dispenses the paper towel is activated. It has long been known that the insertion of an object with a dielectric constant in a volume with an electromagnetic field will tend to modify the properties observed by the electromagnetic field. The ownership of a hand, which has a record
The dielectric near water, is enough to alter the net capacitance of a suitable detector circuit.

An embodiment of the invention comprises a balanced bridge circuit. See figure 8A. He component U1A 90 is a comparator (TLC3702 158) configured as a oscillator. The oscillation frequency of this component U1A 90 of the circuit, can be considered arbitrary and not critical, in as regards the operation of the circuit. The period of oscillator is set by the elements Cref 92, Rhys 94, the adjustment resistance, Rtrim 96, where the adjustment resistance It can be varied and resistances of Rrange 152 adjustment range They are fixed. Rrange 152 resistors allow you to set limits on the range of adjustments, resulting in an easier adjustment. The band adjustment is narrow, since only one part can be varied of total resistance. Consequently, only one can be used potentiometer, simplifying the setting of Rtrim 96. A value of Rrange 152 for the scheme illustrated in Figure 8A can be 100 k \ Omega. Rtrim 96 can have a range of 10 k \ Omega settings at 50 k \ Omega. The output signal on pin1 98 of the component U1A 90 is a square wave, as illustrated in Figure 9A. Cref 92 is loaded by the output, along with ANT 100, holding both the oscillation and measuring the capacitance of the adjacent free space.  The signals resulting from the action of the load are applied to a second comparator, U1B 102, on pin5 104 and pin6 106 (figure 8A). These signals appear as waveforms exponentials, as illustrated in Figure 9B and in Figure 9C.

The simplest form of a comparator is a high gain differential amplifier, made with transistors or With an operational amplifier. The operational amplifier goes to a positive or negative saturation according to the difference of input voltages, because the voltage gain is typically greater than 100,000, the entries will have to be equal within a fraction of millivolt, so that the output is not completely saturated. Although an ordinary operational amplifier Can be used as comparator, there are integrated circuits special intended for this use. These circuits include the LM306, LM311, LM393 154 (Figure 8A), LM393V, NE627 and TLC3702 158. The LM393V is a low voltage derivative of the LM393 154. The LM393 154 It is an integrated circuit that contains two comparators. The TLC3702 158 is a dual micropotence comparator with CMOS 156 outputs in contraphase Figure 8B (prior art) is a scheme that shows the different output structures for the LM393 and the TLC3702. Exclusive comparators are much faster than ordinary operational amplifiers.

The output signal on pin1 98 of the component U1A 90, for example a TLC3702 158, is a square wave,  as illustrated in figure 9. In the second entries comparator, U2B 102, two waveforms are generated. The first comparator 90 is functioning as an oscillator that produces a square wave clock signal, which is input to the input of the U2A 108 flip-flop circuit clock, which can be, by example, a bistable circuit D No. 14013 from Motorola.

Running the first comparator as a Schmitt oscillator trigger, the first comparator U1A 90 is willing to have a positive feedback at the entrance no inverter, terminal3 110. Positive feedback ensures a fast transition out, regardless of the speed of The input waveform. Rhys 94 is chosen so that produce the required hysteresis, together with the resistance of polarization Rbias1 112 and Rbias2 114. When these two resistors polarization Rbias1 112 and Rbias2 114 and the resistance of Rhys 94 hysteresis are the same, the resulting threshold levels are 1/3 V + and 2/3 V +, where V + 158 is the supply voltage. The actual values are not especially critical, except that all three resistors Rbias1 112, Rbias2 114 and Rhys 94 must be equal For a proper balance. For these three resistors you can use the value of 294 k \ Omega, in the scheme illustrated in the figure 8A.

An external lifting resistor, Rpullup1 116, which can have a value, for example, of 470 \ Omega, is only necessary if an open collector comparator is used, such as an LM393 154. The comparator 154 acts as an output of open collector with a grounded transmitter. For a consumption low power, better performance is achieved with a comparator CMOS, for example, the TLC3702, which uses a cmos 156 output in contraphase The signal at terminal3 110 of the U1A loads a Cref 92 capacitor and also charges an ANT 100 sensor with a capacitance that Cref 92 is designed to approximate. A Cref value for the scheme in Figure 8A, for the design of Most current plate, on which it depends, is around 10 pF. As the square wave synchronism is effectively integrated by Cref 92 and the capacitance of ANT 100, two exponential signals appear in terminal5 104 and terminal6 106 of the second comparator U1B, to through the Rprotec 160 static protection resistors. The Rprotec 160 resistors provide a limiting resistance which reinforces the inherent static protection of the lines of comparator input, particularly in the case of the pin5 104 of U1B 102. In the scheme illustrated in Figure 8A, a value typical for Rprotec 160 could be 2 k \ Omega. One of the two exponential waveforms will be greater, depending on the settings of the adjustable resistance Rtrim 96, Cref 92 and ANT 100. The comparator U1B 102 resolves small differences, communicating logical levels at its output, pin7 118. Waveforms may be established initially, based on a ANT 100 capacitance of a given amount. However, at introduce a hand, for example, in the detection field of the ANT 100 antenna, the capacitance of ANT 100 increases significantly and the previous relationship of the waveforms, which were fixed with a lower capacitance ANT100, it invest. Therefore, the logic level output on pin7 118 changes, and the status of the flip-flop circuit d 108 changes through the entry in pin5 of the bi-stable circuit D 108.

The second comparator 102 provides a signal of digital quality to the flip-flop circuit D 108. The circuit flip-flop D, U2A 108 interlocks and maintains comparator output U1B 90. In this way, the second comparator is doing Really an analog to digital conversion. A circuit Suitable flip-flop D is a Motorola 14013.

The presence, and then the absence, of one hand can be used to start the motorized mechanism in a paper towel dispenser, for example. An embodiment of the proximity detector uses a single cable or a combination of cables and copper paper tape that has a proper shape for a detection field. This system is very tolerant for non-conductive elements, such as paper towels, placed in field. A hand is conductive and is attached to a conductor a lot greater in free space. Bringing a hand near the antenna serves to increase the apparent capacitance of the antenna in space free, forcing detection.

The shape and placement of the detector antenna of proximity (figure 8A, 100) becomes something important when the proximity detector is operated correctly. The experimentation showed that an appropriate place was in the direction of lower front of the dispensing unit. The antenna (figure 8A, 100), it was laid about two thirds of the length of the dispensing unit, in a modular unit, replaceable by above the removable dispensing tray 62 (figure 3). This Modular unit would be indicated in Figure 3 as 120.

A detection of the detection circuit of proximity (figure 8A) in module 120 activates a bistable circuit  engine control, so that when you remove your hand it will fire Engine cycle start. The end of the cycle is detected by middle of a limit switch which, when closes, makes a reset of the bistable circuit and stops the engine. You can also start a cycle by closing a switch manual.

A wide range of sensitivity can be obtained varying the geometry of the antenna and coordinating the capacitor of reference. Small antennas have an adequate short range for push buttons without contacts. A large antenna could be arranged as a detector of people the size of a door frame. Other Sensitivity factor is the element applied as Rtrim. Whether replaces Rtrim with an adjustable coil, exponential signals they become resonant signals with phase characteristics strongly influenced by capacitive changes. Consequently, the adjustment with coils can be used to Increase range and sensitivity. Finally, they can be added circuits to antenna 100 to improve range and directivity. As a class, these circuits are called "guards" or "guard electrodes", old in the art, which are a type screen activated with the same potential as the antenna. A equal potential ensures that there is no charge exchange, effectively shielding the saved area of the antenna, making it directive.

The antenna design and the layout of Application setting of the paper towel dispenser is they choose in such a way that they provide adequate reach and cost minimum. The advantages of using a stored antenna and a coil Adjustable are that the detector unit can be made smaller.

From a security point of view, the circuit is designed so that a detection will keep the circuit bistable motor control in reset, thus stopping the mechanism. The cycle can then start again when it ends the detection.

The dispenser has additional switches in the control module 54. Figure 3 shows a switch 134 from "towel-length-to-dispense-once" ("length"). This switch 134 is important to control  the length of paper towel to be dispensed in each dispensing of towel. It is important to set daily by the owner of the dispenser to determine the cost (for the owner) in comfort function (for the user) of obtaining a large piece of Paper towel at one time.

A second switch 136 something similar is the switch 136 of "time-delay-before-being-able-to-activate-the-dispensing-of-another-paper-towel",  (or "time-delay"). The longer the time delay is set, the less likely it will be Let a user wait for many towels to be dispensed. This tends to save costs to the owner. By shortening the delay tends to greater comfort for the user.

A third switch 138 is the setting of sensitivity for the detection circuit. This setting of sensitivity varies the resistance of Rtrim 96 (Figure 8A). One time that an effective antenna configuration 100 is established (figure 8A), the distance from the dispenser can be varied. Typical use actual may require a sensitivity of one to two inches (2.54 to 5.08 cm), instead of four to six inches (10.16 to 15.24 cm). This is done to avoid an unwanted dispensing of towel from paper. In a hospital facility, or a doctor's office, Sensitivity adjustment can be done low enough to avoid the unwanted dispensing of paper towels. On the other hand, in a particular workplace, the sensitivity could be set quite high, so that the towel is very easily dispensed paper.

Although it is well known in the art how to do These switches according to the desired functionalities, a triad of switches can increase the utility of the mode of embodiment of this invention. The system, as illustrated in the present embodiment, it has reduction properties of costs, improved hygiene, improved ease of operation and ease of maintenance. This mode of embodiment of the invention is designed for low consumption of power, compatible with the operation of a battery or package of batteries In this embodiment, a 6V DC power. A eliminator of batteries for continuous operation in a fixed place. There's a passive battery power monitor that will turn on a LED indicator if the input voltage drops below a voltage specified

A second embodiment of this invention It comprises a second electronic proximity sensor. The second detector circuit is a miniaturized proximity sensor, with micro-power, based on capacitance, designed to detect the approach of a hand to a dispenser of towels. Its characteristics are stable operation and a three position sensitivity selector.

Figure 10 shows the complete circuit of the proximity detector In order to examine the circuit more carefully, figure 10 is divided into sections 10A to 10E. These component circuits are illustrated separately as Figures 10A to 10E, corresponding to the cast illustrated in the figure 10.

At the heart of the proximity detector there is a asymmetric adjustable rectangular wave oscillator that works in the range from 24 kHz to 40 kHz, as illustrated in figure 10A. A Once an initial setting has been set, it is not reset again during operation, normally. The characteristic of asymmetry to have a longer connection time and a time of shorter disconnection, allows a more usable signal, that is, Longer connection time. This range of oscillation from 24 kHz to 40 kHz provides a basis for high sampling rate of environment to detect capacitance changes, as detailed in continuation. As illustrated, a quick comparator, XU2A200, has a positive feedback through XR18 202 from the output terminal1 204 (XU2A) to terminal3 206 (XU2A) positive input. The comparator works like an oscillator Schmitt trigger with positive feedback to a terminal non-inverting input Positive feedback ensures fast output transition, regardless of the speed of the input waveform. As the XC6 208 capacitor gets load, terminal3 206 of the XU2A 200 comparator reaches 2/3 XV_ {DD}. This tension of 2/3 XV_ {DD} is maintained in the terminal3 206 for the voltage divider network XR17 212 and XR20 214, and the positive feedback resistance XR18 202 which is in parallel with XR17 212, where XR17 212 and XR20 214 and XR18 202 are equal resistance all of them. The simplest form of a comparator is a high gain differential amplifier, made with transistors or with an operational amplifier. He operational amplifier passes to a positive or negative saturation according to the difference in input voltages, because the voltage gain is typically greater than 100,000, the inputs they will have to be equal within a fraction of millivolt, with so that the output is not completely saturated. Although a ordinary operational amplifier can be used as comparator, there are special integrated circuits intended for this use. For a low power consumption, you get a better performance with a CMOS comparator, such as a TEXAS INSTRUMENT (registered trademark) TLC3702CD (registered trademark) 158 (Figure 8B). He TLC3702 158 is a dual micropotence comparator with CMOS outputs 156 in contraphase (figure 8B). These exclusive comparators are much faster than operational amplifiers ordinary.

When a transition takes place, the exit at output terminal1 204 passes to a relatively negative value, then XD5 216 is in a forward driving state, and the capacitor XC6 208 is preferably discharged through the resistance XR15 218 (100 kΩ) and diode XD5 216.

The time constant to load the capacitor XC6 206 is determined by resistors XVR1 220, XR13 222 and XR15 218. Resistance XR15 218 and diode XD5 216 determine the time constant for capacitor discharge XC6 208.

The reset time is set at 9 \ mus by XD5 216 and XR15 218. However, the source of waves rectangles supplied by the exponential to the antenna, can vary from 16 \ mus to 32 \ mus, using resistance variable XVR1 220 and resistors XR13 222 and XR15 218. Once set for operation, the variable resistance is not change The asymmetric oscillator can generate more signal (16 \ mus a 32 \ mus), compared to the reset time. Time replacement is not especially important, but the level of replenishment is both crucial and constant. Waveform exponential always begins a "voltage drop of the diode" (vbe) above the negative line due to the voltage drop of the polarized diode towards the conduction of XD2 224 (figure 10B). A "diode voltage drop" (vbe) is typically in the range 0.5 V to 0.8 V, or typically around 0.6 V.

The dual diode XD4 226 (figure 10A) provides protection against static electricity. Terminal1 228 of XD4 226 will drive when terminal 230 is at least one fall from diode voltage below ground, or negative trace. He terminal2 232 will drive when terminal3 230 is at least one diode voltage drop above VDD 234. Therefore, the Signal level at terminal3 230 is limited to the -vbe range to VDD + vbe, thus eliminating the voltage points characteristic of the "static", which can be induced by lighting or by the operation of electric motors, for example. The static is mainly through internal mechanisms of the dispenser of towels and paper movement, and is unloaded carrying a moving hand near the sensor.

Asymmetric square wave loads antenna 236 (Figure 10B) through resistors XR9 238 and XR4 240. The sum resistance, XR, is equal to XR9 238 plus XR4 240, or 1.7 M \ Omega, for the example of values illustrated in Figures 10 and 10B. The antenna 236 forms a conducting side of a capacitor, while the atmosphere or other materials form a dielectric between the antenna as a conductive element and other materials drivers including buildings and the land itself as a second conductive element The capacitance C of the antenna 236 in relation at "free space" is approximately 7 pF to 8 pF, as experimentally determined, leading to a time constant \ tau, where \ tau is equal to RC. Therefore, the constant of time for the values in the example is around 13 \ mus.

If a person's hand is placed in the vicinity of the circuit antenna, the capacitance of the antenna with the free space can be double, up to about 15 pF, with a longer resulting time constant and an exponential waveform of smaller amplitude. The time constant ta increases to about 26 mus. Although it is possible to directly compare the signals, it is also desirable to have an operating circuit as stable as possible while retaining high sensitivity and minimizing false positives and false negatives with respect to detection. To help achieve these goals, the condition is first conditioned or processed.
signal.

Looking at the operational amplifier XU1A 242, the waveform (of the signal) sees a very high impedance, since the Operational amplifiers have a high input impedance. The impedance on the antenna side 236 of the amplifier operational 242, in the form of resistance, is about 1.9 M \ Omega. The impedance on the other side of the amplifier Operational is of the order of 5 k \ Omega. In order to provide an intermediate stage of impedance for the signal, the UX1A 242 operational amplifier as a unit follower with a voltage gain of 1.0, that is, the gain given by V_ {out} / V_ {in} is equal to one. The unit follower has a input side resistance (of the operational amplifier) of about 1.0 T \ Omega (10 13 \ Omega). The impedance of output (from the operational amplifier) is in the range around from 40 to 600 to several thousand ohms. Consequently, this unit follower configuration serves to isolate or make intermediate stage of the high impedance circuit upstream with with respect to the low impedance circuit downstream.

The XR2 244 resistor acts as a limiter of current, since the current is equal to v / XR2 in XR2 244. It provides additional protection against static with the pair of diodes XD3 246 in the same way as with the pair of diodes XD4 226 (figure 10A). Terminal1 248 of XD3 246 will drive when terminal3 250 is at least one voltage drop of the diode below ground, or negative stroke. Terminal2 252 will drive when terminal3 250 is at least one voltage drop of the diode above VDD. Therefore, the signal level in the terminal 3 250 is limited to the range -vbe to VDD + vbe, so that the tension points characteristic of the "static."

Asymmetric oscillator pulses, after detect the capacitance that includes or does not include a dielectric next equivalent to that of a next hand, they act on the terminal 254 positive (non-inverting) input of the operational amplifier unit follower 242, to generate a linear output at its terminal 256 output The status of the output terminal is determined in first by the length of the activated asymmetric pulse and, within the "activated" pulse time, the time that it takes to charge antenna 236 (as a capacitor) and the time in download via XR2 244 to input terminal 254 no investor The load-time-constant  It is 13 \ mus to 26 \ mus. The download-time-constant is 0.8 \ mus to 1.6 \ mus. To charge antenna 236 at a certain load Q, for a capacitance based on the constant "free space" dielectric of \ varepsilon_ {0}, is that is, C \ varepsilon_ {0}, a voltage of V = is required Q / C \ varepsilon_ {0}. In the case of a capacitance, for C \ varepsilon_ {0} + \ varepsilon example that includes the hand detection in the "free space", the tension required to store the load Q is Q / C \ varepsilon_ {0} + \ varepsilon. But nevertheless, C \ varepsilon_ {0} + \ varepsilon is approximately double of C? 0, so that the peak hand strain detected is about half of the case in which there is no present no hand

Diode XD1 258 allows positive driving forward but cuts the negative backward driving of a variable signal pulse Forward current, or peak positive current, tends to charge the capacitor XC5 260. The XD1 258 diode, the XR8 262 resistor, the XC5 260 capacitor and the purge resistor XR10 264 comprises a detector network of peaks XD1 258 and XC5 260 capture the positive peak of the shape of exponential wave XR8262 prevents the oscillation of XU1A 242. XR8 262 limit the load time constant to 5 ms, where XR8 262 is 4.99 k \ Omega and XC5 260 is 0.1 µF. This has an effect averaging over the detection of spikes and prevents the tips of noise recharge the detector. The XR10 264 resistor discharges the detector with a half second time constant.

When the hand is detected, the stored load in XC8 260 it is such that the tension is sufficient to raise the input of the non-inverting terminal 266 of the operational amplifier XU1B 268 above 1/2 XVDD, so that it activates the output of the operational amplifier at a linear voltage range usable.

The combination of resistance XR1 270 (for example 499 k \ Omega) and capacitor XC1 272 (for example, 0.1 µF) comprises a low pass filter with a cutoff frequency of 1 / XR1-XC1 (for example, 20 Hz), which corresponds to the time constant of XR1-XC1 (for example, 50 ms). This filter is to reject large noise of 50 Hz or 60 Hz. These "high" frequencies are effectively shorted to land. It is particularly useful that the proximity detector of the Towel dispenser be fed from an AC source coupled. However, the ubiquity of the feed frequency AC does however make this protection desirable.

The signal is then amplified by means of an operational amplifier XU1B 268, which has a gain of 22. The XR5 277 resistor serves as the resistance of Feedback for negative input terminal 279 (inverter) of operational amplifier 268. There is a compensation of ½ XV_ {DD} provided by the voltage divider network of XR3 274 and XR11 276. The output rests on the negative line until a peak exceeds ½ XV_ {DD}. The charging time setting, XVR1 is it becomes a very simple and sensitive way to adjust to this threshold. A 3V adjustment between the test points is recommended XTP1 278 and XTP2 280. This adjustment is made with all loads external capacitive (i.e. plastic and metal components) that be in place.

The output comparator 282 (figure 10D) is connected to signal processing of operational amplifier 268 (figure 10C) by means of capacitor XC3 284 of self-compensation (figure 10D). This makes the circuit be insensitive to the DC levels of the signal, but sensitive to transients, for example a moving hand. As long as the charging time setting function remains in A linear range, the sensitivity to a moving hand will be stable.

The XC4 286 capacitor allows tracking reference level (REF) 288 with an approximate noise of 50 Hz or 60 Hz in signal 290 and do not cause erroneous output pulses, since that the AC noise will also track the input REF 288 (not inverter) to comparator 282.

The output stage of the proximity detector is implements as a variable threshold comparator, XU2B 282. The signal is set with a voltage compensation, where the resistors XR7 292 and XR12 294 are equal and divide the voltage V_ {DD} in two segments of ½ V_ {DD}. Three are provided sensitivity settings with SW1 296, high, medium and low. These adjustments include the one in which the reference voltage is the drop of tension in XR6 298 (499 K \ Omega) being the rest of the divisor voltage equal to XR19 300 (453 k \ Omega) plus XR16 302 (20 K \ Omega) plus XR14 304 (10 k \ Omega). This is the high setting, since that the reference base voltage (V_ {pp} .499 / [499 + 483]) is greater, but almost equal, to the value of the base signal (V_ {DD} .499 / [499 + 499]). The signal must overcome, that is, be done less than the reference voltage (since the input is an input  inverter), in order to pass exit 306 of the high level comparator XU2B 282 and activate, for example, the interlocking of the motor control (not illustrated in figure 10D). The setting of medium sensitivity, in figure 10E, of switch XSW1 296 (by bridge over XR14, 304 of 10 k \ Omega by means of switch XSW1 296) extends the difference between the signal and the reference levels Low sensitivity setting (making a bridge over XR14 304 10 k \ Omega and XR16 302 20 k \ Omega per middle of switch XSW1 296), further expands the difference between Signal and reference levels. Consequently, you must overcome a major difference between the signal and the voltage of reference to activate the motor by means of the XU2B 282 comparator and the motor control interlock (not illustrated in the figure 10D).

The entire sensor circuit works continuously at approximately 300 µA with a supply voltage (XV_ {DD} 234) of 5 V.

The most spectacular example of the formation of static electric charge caused by the mechanical separation of cargo is a big storm with violent presentations of lightning and associated thunder. A problem of formation of static quieter but more pernicious is the one associated with the destruction of electronic circuit chips integrated by static undesirable discharges in conductors susceptible to circuit. A common occurrence of the discharge of the formation of mechanically originated static charge happens when a person walking on a carpet on a dry day, typically cold and has an unpleasant experience, although it does not cause damage, of unloading that load with the contact of an object set to land.

A similar situation occurs in a paper towel dispenser. However, in it, the separation of charges tends to originate when the paper towel is separated from the main roll by tearing it along a guide bar, or a smooth or serrated blade. Some mechanical load separation can also take place by the action of the sheet of paper towels sliding along the edge structures and the dispenser rollers. In many places where a paper towel dispenser is placed there is no access, or it is not easy, to a cable or conduit placed
ground of a 110 V or 220 V power supply system, or ground rods or other grounded conductors.

Consequently, the solution of this invention. To ground the formation of static electricity in a paper towel dispenser, a high conductivity ground wire connects the components dispenser internals that are subject to load accumulation static electric The high conductivity ground wire is connects to an electro-mechanical contact in the part outside of the dispenser. A metallic contact between the path of high conductivity and, for example, the wall against which it is mounted the dispenser, provides an electrical path for the dissipation of the static electric charge formed in the dispenser Towards a local electric land.

The first step is to provide a low path impedance to collect static electric charge in the dispenser and take it to a contact on the wall. Figure 11A shows a side of the 2002 paper towel dispenser with a 2004 access hole for the ground wire (not shown) and shows a molded rib 2006 that prevents the cable from low impedance ground (not shown) make contact with a wheel  Toothed crazy. The crazy cogwheel is not illustrated. This Rib 2006 may be molded into the structure. The rib helps route the ground wire away from the path of a potentially interfering mechanism. In figure 12B it can be seen the 2016 ground wire. The access hole provides a convenient input to allow routing the ground wire of Low impedance to rear wall contact.

The characteristics of the chassis structure provide a solution to fix both the 2016 ground wire (figures 12B, 12C, 15) to the 2020 rear wall contact (figures 12C, 13, 14B) how to fix the metal wall contact 2020 to the dispenser chassis. For wall contact (no illustrated), there is a 2008 screw (figure 11C) and ribs 2010 (figure 11C), to join the wall contact to the chassis. This is seen in Figure 11B and in a different view in the figure 11C. The wall contact may be screwed to the chassis and ground wire may be attached to the contact of the wall with the same screw.

As the rollers with tips tend to pick up the initial static electric charge, the ground wire is laid from the tip rollers to the wall contact. So, the figure 12A shows the 2012 gear cover with a molded rib in it, which holds the spring 2018 contact (figures 12C, 13, 14B) on your site. Keeping the ground wire in a line relatively straight from the cargo collection near the source of charge generation, the 2016 ground wire is allowed to have a minimum length (figures 12B, 12C).

The actual contact is made by the 2016 cable Earth with a spring 2018 clamp, by means of junction (2026, figure 12C) of a spring clamp. The spring has spring clamp means as part of its structure. The Figure 12B shows the 2016 ground wire and its connection to the clamp Spring 2018 (figures 12C, 13, 14B). A spring 2019 of compression (figure 16) makes contact with the metal shaft (2022, Figure 15) of the tip roller by means of the pressure of the spring, providing a mechanical and electrical contact. The static electricity accumulated in the tip rollers can transfer from the tip rollers to the metal shaft (2022, Figures 12B, 12C, 15) of the tip rollers. Then the Static electricity can be transferred through the 2018 clamp from spring to ground wire 2016. The 2016 ground wire is held by spring clamp means (2026, figure 15) to the 2018 spring clamp (figures 12C, 13, 14B).

Figure 13 is a perspective view that Displays the 2020 spring clamp of the wall contact and the 2016 ground wire, which is partially hidden when it enters in the 2004 access hole. The 2020 spring clamp set to ground at the wall contact is on the back side of the paper towel dispenser. It is connected to the 2016 cable of land, which is hidden by the structure of the 2002 dispenser. In Figure 12C, towards the front side of the 2002 dispenser, the 2016 ground wire is connected to the 2018 spring contact that connects mechanically and electrically to the 2022 axis of the tip roller by spring pressure. How Figure 12C shows, the ground contact goes from the roller tips (not shown) to metal shaft 2022 of the tip roller a through a spring 2018 clamp (figures 12C, 13, 14B). He ground contact continues through the 2016 ground wire to the 2020 grounding spring clamp on the contact of the wall. When the dispenser 2002 is mounted on a wall, the 2020 grounding spring clamp on the wall contact, acting as a partially compressed spring, press against the wall to maintain a mechanical pressure contact that provides an electrical conduction path to the wall from the static formation zones in the 2002 dispenser of towels

Figure 13 shows the cable path 2016 of land from where it enters the access hole 2004 towards the inside the dispenser 2002. The 2016 ground wire continues until it comes into contact with the 2020 spring clamp grounded at the wall contact. The 2016 ground wire is attached to the 2020 grounding spring clamp on the contact of the wall by means of a screw, nail, welding or others common methods of fixing a ground wire to a contact metallic used to complete the path to land.

It can be seen that the dispenser may be made of materials or combinations of alternative materials. By example, in the case where the rear chassis of the dispenser is Made of galvanized steel or stainless steel, the chassis itself can be formed with one or more integrated spring contacts of wall. The ground wire, in these embodiments, can be attached, but not limited to it, by means of screws, nails, welding, copper welding or autogenous welding. In other embodiment, the rear chassis can be plastic, but with metal strips. These metal strips can be also formed with one or more integrated spring contacts. He Ground wire can then be attached to the metal strips. Again, the dispenser can be made entirely of metal, for example stainless steel. In this embodiment, you can use the ground wire system, or the path Electrical ground can be from the spring contact, which presses against the tip roller to the metal housing of the dispenser of paper towels, on the back wall, by means of one or more spring contacts integrated into the wall.

Figure 14A shows the opening 2026 in the 2028 rear cover for grounding spring clamp on The wall contact. The placement of the opening tends to determined by keeping a shorter ground wire, along with structural manufacturing considerations for the chassis of the paper towel dispenser.

Figure 14B shows the 2020 clamp on its site earthing spring on the wall contact, ready so that the 2002 paper towel dispensing unit can be mounted in such a way that you press that spring clamp on grounded at the wall contact against the wall and hold a Good mechanical and electrical contact.

Figures 15 and 16 illustrate the dispenser 2002 with the front cover removed, they show additional details of the connection from the tip roller (not shown) to the metal shaft 2022 of the tip roller and then through a 2018 contact spring that connects to the compression spring (not shown) of the tip roller and means 2026 for connecting the clamp spring connected to the 2016 ground wire and the spring clamp grounding (not shown) at the wall contact, with the wall (not illustrated).

The invention is described in more detail in the following conclusive paragraphs of the disclosure, which describe additional aspects of the invention.

A first additional aspect of the invention is an apparatus for dispensing paper from rolls, including this apparatus: means for holding and positioning at least one first and second paper rolls with respect to each other; means for dispense paper from the first roll; paper dispensing means from the first and second rolls simultaneously when the First roll is reduced to a predetermined paper diameter; means for positioning the first depleted roll for replacement, no need to remove the second roll; and means to dispense from the second roll and the replacement roll simultaneously, when the second roll is reduced to a paper diameter predetermined.

A second additional aspect of the invention is a dispenser for a roll of paper sheet. The dispenser includes: a first support adapted to hold a first roll of paper; a second support adapted to hold a second roll of paper; a third support rigidly connected to the first and second supports, where the third support can rotate around an axis; and a transfer bar through which the role of the second roll can be fed with first roll paper to dispense jointly.

Preferably, the second dispenser Additional aspect of the invention further includes a housing that it has a swivel lid towards an open position; where he first, second and third supports are accessible when said cover of the accommodation is open.

Preferably, the second dispenser Additional aspect of the invention further includes a bar of interlocking, where the third support is adapted to fit arranged in a locked position by means of the bar interlocking, the interlocking bar being adapted to unlock the third support and allow said set of Carousel rotate around the axis. More preferably, the third support has the propensity to turn when it is unlocked.

Preferably, the transfer bar includes two legs adapted to come into contact with ends opposite of a residual roll, to come into contact with the opposite ends of the core tube of a residual roll when said residual roll is exhausted and only the core tube remains and in which the two legs are joined by an elongated bar. Plus preferably, the dispenser includes: a feed roller to drive the paper from the rolls. Transfer bar It is rotatably arranged with its elongated bar adjacent to the feed roller and transfer bar legs adjacent to the rotating pivots of the rolls when the roll residual is in position. Even more preferably, the dispenser also includes: a tip roller arranged for run the feed roller to drive the paper from the rolls between the feed and tip rollers.

A third additional aspect of the invention is a dispenser for a roll of a sheet of paper, including the dispenser: a first support for a first roll of paper; a second support for a second roll of paper; and a third support for said first support and for said second support, the third rotating support around an axis; a roller of feeding; a tip roller arranged to operate in consonance with the feed roller; a mechanism of activation to activate the feed roller to dispense paper towels arranged between the feed rollers and tips More preferably, the dispenser further includes: a transfer bar adapted to feed paper simultaneously from the first and second rolls. Even more preferably, the transfer bar also includes two legs adapted for come into contact with opposite ends of a residual roll, to come into contact with opposite ends of the core tube of a residual roll when said residual roll is depleted and only the core tube remains, the two legs being joined by a bar elongated Even more preferably, the dispenser includes also a feed roller to drive the paper from the rolls, where the transfer bar is arranged swivel with its elongated bar adjacent to the roller power and transfer bar legs adjacent to the rotating pivots of the rolls when the residual roll is in position Even more preferably, the third support has propensity to turn when unlocked. Even more preferably, the dispenser also includes an interlocking bar, where the third support is adapted to be arranged in a position interlocked by the interlocking bar, the bar being interlocking adapted to unlock the third support and allow Let the carousel assembly rotate around its axis. Even more preferably, the dispenser further includes a housing that it has a lid that can rotate towards an open position; where the first, second and third supports are accessible when the Housing cover is open.

A fourth additional aspect of the invention is a method to dispense paper from a roll. The method includes The steps of: supporting a first roll of paper in a first position; support a second roll of a sheet of paper in a second position; spin the first and second set rolls between the first and second positions around a horizontal; and simultaneously dispense paper from the first and second rolls Preferably, the method further includes the steps of: interlock the rolls so that they cannot rotate between the first and second positions; and unlock the rolls so that they remain free to rotate around the horizontal axis. Even more preferably, the method further includes the step of propending  to the first roll so that it rotates when it is unlocked. Even, Additionally, the method also includes the step of positioning two legs of a transfer bar so that they come into contact with opposite sides of a residual roll and come into contact with opposite sides of the core tube of the residual roll when said residual roll is exhausted and only the tube of the nucleus; and join the two legs together by an elongated bar. Yet Additionally, the method includes the steps of: using a roller feeding to drive the paper from the rolls, where the transfer bar can be rotatably arranged with your elongated bar adjacent to the feed roller, and said legs of said transfer bar adjacent to said pivots rotating the rolls when the residual roll is in its position. Even additionally, the method includes the steps of using a tip roller arranged to operate with said feed roller, to drive the paper from the rolls between the feed and tip rollers.

A fifth additional aspect of the invention is a method that includes the steps of: supporting a first roll of paper on a first support; support a second roll of paper on a second support; support said first and second supports with a third support, where the third support can revolve around of a horizontal axis; and dispense paper towels between a roller of feeding and a roller of ends. More preferably, the method includes the step of using a transfer bar; where the second roll can be fed with the first roll to Dispense together. The method may include, even more preferably, the steps of: positioning two legs of a bar transfer so that they come in contact with the opposite ends of a residual roll and come into contact with opposite ends of the core tube of the residual roll when the residual roll is has run out and only the core tube remains; and put the two together legs joined by an elongated bar. The method can even more preferably include the step of using a roller feed to drive the paper from the rolls, where the bar transfer can be rotatably arranged with its bar elongated adjacent to the feed roller, and the legs of the transfer bar adjacent to said rotating pivots of the rollers, when the residual roll is in position. Even more preferably, the method further includes the step of propending to the first roll so that it rotates when it is unlocked. Even more preferably, the method includes the steps of: interlocking the rolls so that they are unable to rotate between the first and second positions; and unlock the rolls so that they are free to rotate around the horizontal axis.

A sixth additional aspect of the invention is a proximity detection circuit that includes: a circuit oscillator that has a period set by a resistance of hysteresis, a variable resistance of adjustment and a capacitor of reference; a balanced bridge comprising a sensor that has a capacitance in an arm of said bridge and a capacitor of reference on the other arm of the bridge where the resistance adjustment variable is adapted to adjust voltage amplitudes on each arm of said bridge; a comparator adapted to compare the tension in each of the arms of said bridge and provide an output voltage; and a flip-flop circuit d with trip in the edge, which is locked and held on the leading edge of the comparator output voltage. The circuit includes, more preferably, an activation switch of the connected motor to receive a bistable circuit output.

A seventh additional aspect of the invention includes: an oscillator circuit that includes a first comparator adapted to provide a clock signal as output; a sensor that has a capacitance; an adapted reference capacitor to balance approximately the capacitance of the sensor, being grounded one side of the reference capacitor; a variable resistance of series adjustment between capacitance of sensor and reference capacitor; a hysteresis resistance adapted, in conjunction with the variable resistance of adjustment and reference capacitor, to set the oscillation frequency of the oscillator; a second comparator adapted to compare voltages on its two input pins measured in resistance adjustment variable, and a flip-flop d circuit tripped with the edge, adapted to interlock and maintain the output of the second comparator, said bistable circuit being synchronized by the output signal of the first comparator.

An eighth additional aspect of the invention is a method to detect small capacitance changes, including  this method the steps of: generating voltage oscillations in a first comparator comprising an oscillator with a fixed period by hysteresis resistance, a variable resistance of adjustment and a reference capacitor, forming a balanced bridge of two arms, the first arm comprising a capacitance sensor  and the second arm comprising the reference capacitor; compare the tensions of each arm of a balanced bridge, where the variable resistance of adjustment adjusts voltage amplitudes on each arm of said bridge; detect a first amplitude of voltage in one place between the sensor and the variable resistance of adjustment, the first voltage being applied to the input pin positive of the second comparator; detect a second voltage in a place between the reference capacitor and the capacitor, being applied the second voltage to the negative tension pin of the second comparator; provide an output voltage in the output pin of the second comparator, the output voltage of the second comparator to be low when the amplitude of the first voltage is less than the amplitude of the second tension; interlock and stay on the leading edge of the output voltage of the second comparator, using a circuit flip-flop d shot with the edge; and reverse an exit state of said bistable circuit when an object is detected that has an increased dielectric constant with respect to the constant dielectric of the air, said object increasing the capacitance in the balanced bridge sensor arm and changing the amplitude of said first tension. Preferably, the method further includes the step of activating a motor switch when a change in the state of the bistable circuit output.

A ninth additional aspect of the invention is a method to detect small capacitance changes, using  a proximity detection circuit, which includes the steps of: generate voltage oscillations in a first adapted comparator as an oscillator, with a period set by a resistance of hysteresis, a variable resistance of adjustment and a capacitor of reference, forming a balanced bridge with two arms, with a first arm comprising a sensor that has a capacitance, and a second arm comprising the reference capacitor; balance approximately the capacitance of the sensor with the reference capacitor, said reference capacitor having a grounded side; set a variable resistance of adjustment, where said variable adjustment resistance is in series between the capacitance of the sensor and the reference capacitor; set the oscillation frequency of the oscillator using a hysteresis resistance, reference capacitor and adjustment of the variable resistance of adjustment; detect a first voltage in a place between the sensor and the variable resistance of adjustment; apply a first tension to the positive input pin of the second comparator; detect a second voltage in a place between the reference capacitor and the capacitor; apply a second voltage to the negative input pin of the second comparator; generate a low level output status of the second comparator, when the amplitude of the first voltage is less than the amplitude of the second tension; generate a high level output status of second comparator, when the amplitude of the first voltage is greater than the amplitude of the second voltage; apply the tension of output on the output pin of the second comparator to a circuit flip-flop d shot with the edge; interlock and keep the exit of the second comparator, using a bistable circuit tripped with the edge; synchronize said bistable circuit with the signal of oscillator output of the first comparator; and detect an increase in the dielectric constant when an object enters the field of sensor detection, causing the object entering the field a increase in the effective capacity of the sensor and a change in the amplitude of the first voltage, thus making the output of the Second comparator change state. Preferably, the method includes the additional step of activating the motor switch when it detects a change in the output status of the circuit flip flop

An additional tenth aspect of the invention is an apparatus for dispensing paper from rolls, including the apparatus: means for holding and positioning at least one first and one second rolls of paper, one with respect to the other; means for dispense paper from the first roll; paper dispensing means from the first and second rolls simultaneously when the first roll is reduced to a predetermined paper diameter; means for position the first depleted roll for replacement, without need to remove the second roll; means to dispense from the second roll and the replacement roll simultaneously when the second roll is reduced to a predetermined paper diameter, and a proximity sensor dispensing means adapted to shoot when a user's hand is within the field of sensor. Preferably, the proximity detector further includes: an oscillator circuit with a period set by a resistance of hysteresis, an adjustment resistor and a capacitor of reference, a balanced bridge having an arm of said bridge a sensor that has a capacitance and having the other arm of the bridge a reference capacitor, the variable resistance of adjustment to adjust the tensions in each arm of said bridge; a second comparator adapted to compare the tensions in each arm of said bridge; and a flip-flop circuit  d shot with the edge that interlocks and stays on the edge front of the output voltage of the second comparator.

An eleventh additional aspect of the invention is a dispenser for a roll of paper sheet, including the dispenser: a first support adapted to hold a first paper roll, a second support adapted to hold a second roll of paper; a third support rigidly connected to the first and second supports, where said third support can rotate around an axis; a transfer bar in which the paper of said second roll can be fed with paper of the first roll to dispense together; a proximity sensor adapted to trigger the paper dispensing when the hand of a user is within the sensor field. The detector includes: an oscillator circuit comprising a first comparator adapted to provide a clock signal as output; a sensor that It has a capacitance; a reference capacitor adapted to approximately balance the capacitance of the sensor, being grounded one side of the reference capacitor; a variable variable resistance connected in series between the capacitance of the sensor and the reference capacitor, a hysteresis resistance adapted to set the frequency of oscillator oscillation together with variable resistance adjustment and the reference capacitor; and a second adapted comparator to compare voltages on the two input pins of the second comparator, measured in the variable resistance of adjustment; and a bistable circuit fired with the edge, adapted to interlock and keep the output of the second comparator, being synchronized the flip-flop circuit by the output signal of the first comparator. Preferably, the dispenser further includes means for provide a selectable dispensed paper length, including the means: motor means for dispensing paper from at least one roll; a first sub-circuit of engine control; a first switch adapted to control the first sub-circuit, the first being adapted sub-circuit to set the paper length dispensed by said motor means in accordance with the adjustment of the First switch The dispenser, in this aspect of the invention, may also include means to provide a delay of selectable time before the dispenser can be reactivated to dispense another length of paper. The media include: motor means for dispensing paper from at least one roll; a second motor control sub-circuit;  a second switch adapted to control the second sub-circuit, the second being adapted sub-circuit to set a time delay for dispense the paper by means of said motor means, according with the setting of the second switch. Preferably, the dispenser also includes means to provide a Selectable proximity sensor sensitivity, including means: a variable capacitor on a branch of the detector proximity based on a balanced capacitance bridge; a third switch adapted to control the variable capacitor, said variable capacitor being adapted to fix the bridge-based proximity detector sensitivity balanced capacitance. Preferably, the dispenser also includes means to provide a path orientation eye-hand-brain, being adapted the orientation to be able to guide a hand towards the sensor proximity of the dispenser; including the media a fake button arranged inside a recess in elevation on the cover, being located the false button near the proximity sensor, being adapted said elevation recess and the false button so that focus a user's field of vision, so that the user He tends to guide his hand towards the false button.

An additional twelfth aspect is a method for dispense paper from a roll when detecting small changes of capacitance by means of a proximity sensor when placing a hand or similar object near the dispenser. The method includes The steps of: supporting a first roll of paper in a first position; support a second roll of a sheet of paper in a second position; spin the first and second set rolls between the first and second positions around an axis horizontal, dispensing paper simultaneously from the first and second rolls; operate as an oscillator circuit at a first comparator adapted to function as an oscillator, being adapted the oscillator circuit to have its period fixed by a hysteresis resistance, a variable resistance of adjustment and a reference capacitor, balancing its two components as in a balanced bridge, the first component being a sensor that it has a capacitance in the first arm of said bridge and being the second component the reference capacitor over a second bridge arm; adjust the amplitudes of the tensions in each arm of said bridge by means of a variable resistance of adjustment; compare the tensions in each arm of said bridge using a second comparator; interlock and stay in the leading edge of the output voltage of the second comparator, using a bistable circuit d shot with the edge. Preferably, the method further includes the step of activating the motor switch, when a change in the state of bistable circuit output.

A thirteenth additional aspect of the invention is a proximity sensing circuit that includes: an asymmetric oscillator circuit having its activation period set by a resistor network that includes a plurality of fixed resistances and at least one variable resistance, and having its deactivation period set by at least one fixed resistance and by at least a single first diode; a first static protection circuit, including a first plurality of diodes, one of said diodes being adapted to drive in the opposite direction to ground, another one of said diodes being adapted to drive towards the power supply; a reset path in which a second single diode provides a discharge path for an antenna, where the antenna is discharged at the same voltage in each period of time; the asymmetric oscillator being adapted to send an approximately uniform amount of charge during its activation period to said antenna; decreasing the antenna voltage when the antenna capacitance increases with a detected object; a second static protection circuit comprising a second plurality of diodes, one of said diodes being adapted to drive in the opposite direction to ground, another one of said diodes being adapted to drive towards the supply voltage; an antenna impedance buffer that includes an operational amplifier that is operated as a unit gain follower, the output terminal of the operational amplifier being fed back to the inverting input terminal; a voltage peak detector that includes a third single diode, a current limiting resistor, a peak storage capacitor and a purge resistor, the third single diode and said peak storage capacitor being adapted to capture the positive peak of the exponential waveforms, the current limiting resistance being adapted to limit the current flow and providing the output of the antenna impedance buffer, a larger phase margin to prevent oscillation, the purge resistance being adapted to providing a discharge path for said peak storage capacitor; a low pass filter adapted to filter alternating current interference frequencies of about 50 or about 60 Hz, the low pass filter comprising an inline resistor and a capacitor with a grounded side; an amplifier with gain and voltage compensation; a self-compensating capacitor adapted to filter changes in DC voltage levels, while allowing the passage of transient signals; a three position switch adapted to provide three levels of detection sensitivity; and an output comparator, adapted to generate a signal output when the signal voltage, applied to the non-inverting input terminal of said comparator, is greater than the reference voltage, which is applied to the inverting input terminal of the comparator. Preferably, the object detected includes a material with a dielectric constant at least equal to half of the dielectric constant of water. Preferably, the transient signal is generated by a moving hand. Preferably, the circuit further includes an activation switch of a connected motor
tado to receive an output of a bistable circuit activated by the output signal of said output comparator.

An fourteenth additional aspect of the invention is a proximity detection circuit that includes: a oscillator circuit comprising a first comparator adapted for provide an asymmetric signal as input to a sensor antenna; an antenna sensor adapted to respond to a change in the dielectric constant in the proximity of the sensor; a first operational amplifier adapted to make intermediate stage between the antenna sensor and a peak detector, where the sensor antenna has a high impedance and the peak detector has a low impedance; a low pass filter adapted to filter noise frequencies in the 50 Hz and 60 Hz range; one second operational amplifier adapted to provide compensation  voltage to an input signal to the second amplifier operational, and to amplify a peak detector signal such as output of the second operational amplifier; a second comparator adapted to generate an output pulse, where the signal from output of the second operational amplifier is an input signal for the second comparator, and is of a duration, amplitude and sufficient rate of change to generate the momentum of exit.

An fifteenth additional aspect of the invention is a method to detect small changes of capacitance, including the method the steps of: detecting time load integration for an antenna detector with a higher dielectric constant; integrate a peak voltage proportional to the load integration time, where the time of load integration is inversely proportional to the constant of resistance-capacitance time; generate a output signal from the integration of the voltage pulse of peak, the output signal being adapted to activate a circuit Logic of motor control. Preferably, the method includes also the step of: activating a motor switch when detects a change in the output status of the flip-flop circuit.

A sixteenth additional aspect of the invention It is a method to detect small capacitance changes using a proximity detection circuit. The method includes the steps of: producing an asymmetric oscillator circuit that has its activation period set by a resistance network that include a plurality of fixed resistors and at least one variable resistance, and that has its deactivation period set  by at least one fixed resistance and by at least a single first diode; provide protection against static using a first static protection circuit, including a first plurality of diodes, one of the diodes being adapted to drive in the opposite direction to ground, and another adapted diode to drive to the power supply; make a replacement of the antenna sensor voltage at a fixed amount, using a reset path in which a second single diode provides a discharge path for an antenna, where the antenna is discharged at the same voltage in each period of time; charge the antenna with an antenna voltage where a quantity of approximately uniform load by means of an asymmetric oscillator during its activation period; decrease tension when the antenna capacitance increases with an object detected with a relatively high dielectric constant; protect against static electricity in the proximity detector, using a second static protection circuit that includes a second plurality of diodes, one of said diodes being adapted to drive in the opposite direction to ground, being adapted another one of said diodes to lead to the voltage of feeding; perform impedance buffer with an antenna impedance buffer, where the buffer comprises an operational gain amplifier unitary, with the output terminal of the operational amplifier to the inverting input terminal; detect a peak voltage using a detector that includes a third single diode, a current limiting resistor, a peak storage capacitor and a purge resistor; capture the positive peak of exponential waveforms using the third single diode and said capacitor of storage of peaks to capture the positive peak of exponential waveforms; limit the flow of current using the current limiting resistor to limit the stream; prevent oscillation by providing the exit of the intermediate antenna impedance memory, a larger phase margin, using the value of the current limiting resistor; provide a discharge path for the condenser of peak storage using a purge resistor; filter alternating current interference frequencies of around 50 and around 60 Hz, using a pass filter low, comprising the pass filter under an in-line resistor and a capacitor with a grounded side; provide a voltage compensation; amplify the signal with an amplifier operational; filter changes in the DC voltage levels of the signals, while allowing to pass to the transient signals generated by a moving hand; provide three levels of detection sensitivity using a three switch positions; generate a signal output, using a comparator output, when the signal voltage, applied to the terminal inverter comparator input is less than the voltage of reference, whose reference voltage is applied to the terminal inverter comparator input. Preferably, the method includes also the step of applying the output voltage on the pin of output of the second comparator, to a logic control circuit shot with the edge. More preferably, the method includes the step of activating a motor switch when a change in the output status of the second comparator.

An additional seventeenth aspect of the The invention is an apparatus for dispensing paper from rolls. He apparatus includes: means for holding and positioning at least one first and a second paper rolls, one with respect to the other; means for dispense paper from the first roll; paper dispensing means from the first and second rolls simultaneously when the first roll is reduced to a predetermined paper diameter; means for position the first depleted roll for replacement, without need to remove the second roll; means to dispense from the second roll and the replacement roll simultaneously when the second roll is reduced to a predetermined paper diameter; and a second proximity detector adapted to fire the means of dispensing when a user's hand is placed within the field of the sensor. Preferably, the second proximity detector includes: an oscillator circuit comprising a first comparator adapted to provide an asymmetric signal as input to a antenna sensor; an antenna sensor adapted to respond to a change in dielectric constant in the proximity of the sensor; a first operational amplifier adapted to stage intermediate between the antenna sensor and a peak detector, where the antenna sensor has a high impedance and said detector of peaks have a low impedance; a second amplifier operational adapted to provide voltage compensation to an input signal to the second operational amplifier, and for amplify a signal from the peak detector as output of the second operational amplifier; a second comparator adapted to generate an output pulse where the second output signal operational amplifier is an input signal for the second comparator, and is of a duration, amplitude and rate of change enough to generate the output pulse.

An eighteenth additional aspect of the invention is a dispenser for a roll of paper sheet. The dispenser includes: a first support adapted to hold a first roll of paper; a second support adapted to hold a second roll of paper; a third support rigidly connected to the first and second supports, where the third support can rotate about an axis; a transfer bar through which the paper of the second roll can be fed with paper of the first roll to be dispensed together; and a second proximity detector adapted to trigger the dispensing when a user's hand is placed within the sensor field. The detector includes: an oscillator circuit comprising a first comparator adapted to provide an asymmetric signal as input to an antenna sensor; an antenna sensor adapted to respond to a change in the dielectric constant in the proximity of the sensor; a first operational amplifier adapted to act as an intermediate stage between the antenna sensor and a peak detector, where the antenna sensor has a high impedance and said peak detector has a low impedance; a low pass filter adapted to filter the noise frequencies of the line in the 50 Hz and 60 Hz range; a second operational amplifier adapted to provide voltage compensation to an input signal to the second operational amplifier, and to amplify a signal from the peak detector as output from the second operational amplifier; a second comparator adapted to generate an output pulse, where the output signal of the second operational amplifier is an input signal for the second comparator, and is of sufficient duration, amplitude and rate of change to generate the output pulse. Preferably, the dispenser further includes means for providing a selectable length of dispensed paper, including the means: motor means for dispensing paper from at least one roll; a first motor control sub-circuit; a first switch adapted to control the first sub-circuit, the first sub-circuit being adapted to set the length of paper dispensed by said motor means in accordance with the setting of the first switch. Preferably, the dispenser further includes means to provide a selectable time delay before the dispenser can be reactivated to dispense another length of paper; those means include: motor means for dispensing paper from at least one roll; a second motor control sub-circuit; a second switch adapted to control the second sub-circuit, the second sub-circuit being adapted to set a time delay for dispensing the paper by means of said motor means, in accordance with the setting of the second switch. Preferably, the dispenser further includes means for providing a selectable sensitivity of said proximity sensor, including the means: a voltage divider on a branch of a reference voltage; a third switch adapted to select combinations of resistances in the branch of the reference voltage, the selected resistances being adapted to set the sensitivity of the sensor of
proximity.

An additional nineteenth aspect of the invention is a method of grounding the dispenser in a local land The method includes the steps of: providing a low internal impedance path from internal positions and over the surface of the dispenser, where loads tend to accumulate of static electricity; connect the low impedance path to a metal contact spring in the wall, arranged to make contact with a ground surface when the dispenser; and download said static electricity charges in a local land through the land interface. Preferably, the method also includes the step of connecting a roller shaft of tips of a paper towel dispenser to a ground wire. More preferably, the method further includes the step of using a spring contact to connect the spindle roller shaft to the ground wire, where the spring contact connects to the axis of the tip roller.

A twentieth additional aspect of the invention is an apparatus for grounding the dispenser. The device includes: a low impedance ground wire; a spring clip grounding in metallic contact; a spring contact arranged so that it connects to a place of accumulation of static electricity in the dispenser, the cable being arranged low impedance ground to connect to the contact spring and to the spring clamp of grounding in metallic contact, the grounding spring clamp being arranged in metal contact to make contact with a wall; being arranged the spring clamp for grounding in contact metallic to connect electrically to a local earth. Preferably, the apparatus also includes the ground wire arranged to connect to the axis of a roller of tips of a paper towel dispenser. Preferably, the apparatus includes in addition the spring contact arranged to connect to a compression spring of the tip roller, where the spring of tip roller compression is arranged to make contact with a metal roller of tips.

A twenty-first additional aspect of the invention includes: a first support adapted to hold a first  paper roll; a second support adapted to hold a second paper roll; a third support rigidly connected to the first and second supports, where the third support can rotate around an axis; a transfer bar through which the paper from said second roll can be fed with first roll paper to jointly dispense; a detector adapted to fire the paper dispensing when a user's hand is placed inside of the sensor field; and a grounding device. The apparatus of grounding includes: a low grounding wire impedance; a grounded spring clamp in contact with a metal wall; and a spring contact arranged for connect to a location of the accumulation dispenser of static electricity. The low impedance ground wire is arranged to connect to the spring contact and the clamp earthing spring in metallic contact with the wall. The earthing spring clamp in metallic contact with the wall is arranged to make contact with a wall by means of The pressure of a spring. The grounding spring clamp on metal contact with the wall is arranged to connect electrically to a local land.

Although the present invention and its advantages have been described in detail, it should be understood that they can be done various changes, substitutions and alterations in this memory without depart from the scope of the invention, as defined in the annexed claims. Moreover, the scope of the present invention is limited to the embodiments Particular process, machine, manufacturing, composition of materials, media, methods and steps described in the report. How you will easily appreciate a person of ordinary formation in the technique, from the disclosure of the present invention, can the processes are used in accordance with the present invention, machines, manufacturing, material compositions, media, methods, or steps, currently existing or to be developed later, that perform substantially the same function or get substantially the same result as the corresponding modes of embodiment described here. Consequently, the annexed claims are intended to include within your reach such processes, machines, manufacturing, compositions of materials, means, methods or steps.

Each of the characteristics disclosed in this report (whose terms include the claims) and / or illustrated in the drawings, can be incorporated into the invention, regardless of other disclosed characteristics and / or illustrated.

The text of the deposited summary is repeated here, as part of memory

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Apparatus for dispensing paper from rolls feeds continuously, roll by roll, and does not require a additional procedure to bring the residual roll to its position. The device has means to support and position the minus a first and a second roll of paper, one with respect to the other; means for dispensing paper from the first roll; media to dispense paper from the first and second rolls simultaneously when the first roll is reduced to a diameter paper default; means to position the first roll sold out to be replaced without removing the second roll; and means for dispensing from the second roll and the roll of replacement simultaneously, when the second roll is reduced to a default paper diameter. The device also has a proximity sensor based on capacity change comprising a circuit according to the principle of a balanced bridge, where detection is based on detecting a phase difference, which depends on the amount of difference or change in capacitance detected The proximity detector detects when a hand near the dispenser, and thereby dispenses a fixed amount of paper towel. Do not continue dispensing towels. Is accurate remove the hand and place it again in the proximity of the sensor. The proximity sensor incorporates circuits for the "static" and for noise immunity. The dispenser incorporates means for dissipate static charges to a local land.

Claims (11)

1. A method of grounding a dispenser (20) of paper towels in a local land, which includes Steps of:

provide a Internal path (2016) of low impedance for electric charges static that accumulate during use of the dispenser (twenty);

connect said Road (2016) low impedance internal components (2022) of the dispenser (20) that are subject to such load accumulation static electric; Y

connect said Low impedance path (2016) to a contactor (2018) arranged to make contact with a grounded surface, when mount the dispenser (20);

wherein said static electric charges are discharged to a local land through the surface set to earth, in which the contactor (2018) is a metallic spring in contact with the wall.

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2. The method of claim 1, wherein The low impedance path (2016) consists of a cable ground, the dispenser (20) comprising a tip roller metallic to drive the paper, which has a shaft (2022) of the roller of tips, and said shaft (2022) of the tip roller is connected to the ground wire. 3. The method of claim 2, which it also includes the step of using a spring contact to connecting said shaft (2022) of the tip roller to the cable land. 4. A grounding mechanism for a paper towel dispenser (20), comprising:

a means to provide an internal path (2016) of low impedance for static electrical charges that accumulate during the use of the dispenser (20); Y

a means to connect said low impedance path (2016) to the components internal (2022) of the dispenser (20), which are subjected to such accumulation of static electric charge; Y

a means to connect said low impedance path (2016) to a contactor (2018) arranged to make contact with a setting surface ground when said dispenser (20) is mounted;

in which static electric charges are discharged to a local land through the surface set to earth, in which the contactor (2018) is a metallic spring in contact with the wall.

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5. A grounding mechanism as in the claim 4, comprising:

a wire of low impedance earth:

a contact of spring connected to said ground wire and arranged to connect to a place of static electricity accumulation in the dispenser (20); Y

a clamp metallic spring grounded in contact with the wall, connected to said ground wire and arranged to make contact, by means of spring pressure, to a wall to make contact With a local land.

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6. A grounding mechanism as in the claim 5, wherein said ground wire is disposed to connect to a shaft (2022) of a metal tip roller of the dispenser (20). 7. A grounding mechanism as in the claim 5, wherein said spring contact is disposed to connect to a compression spring of a tip roller, which is arranged to make contact with a tip roller metallic (2022). 8. A dispenser (20) that includes the mechanism grounding of any of claims 5 to 7. 9. A dispenser (20) as in claim 8, in which the dispenser includes:

a first support adapted to hold a first roll of paper;

one second support adapted to hold a second roll of paper;

a third support rigidly connected to the first and second supports and that can rotate around an axis; Y

a loaf of transfer through which paper can be dispensed from the second roll, along with paper from the first roll.

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10. A dispenser (20) as in the claim 8 or 9, further including a detector adapted for trigger the paper dispensing from the dispenser, when places a user's hand within the field of a sensor. 11. A paper dispenser (20), which understands:

a dispenser according to claim 8;

a support adapted to hold a roll of paper (66, 68);

a mechanism of power driven by a motor (56), adapted to receive and dispense paper from the roll (66, 68);

a spring (2018) of contact with a surface, adapted to make contact directly with a mounting surface external to the dispenser (20), when the dispenser is fixed to the surface of mounting.