EP0483314B1 - Towel dispenser - Google Patents

Abstract

Unused towel rolled up in a shell (4) is guided between a roller (38) and a tracer (40) for detecting the towel end and via a transport roller (6a), forms a loop and runs via a transport roller (6b) to a roller (13) guided in slots (14a,b) and intended for receiving used towel. To ascertain whether the loop is being used or not, there is a movement sensor (20) with a bar (22) which is suspended rotatably about a horizontal axis and to which is attached a batten (23) via which the towel (5) is guided. Clamped in the bar (22) is the upper end of a piezoelectric element which at its lower end is clamped between parts connected to a sensor housing (21). Since a distinction can be made between use and non-use, it is possible for released unused towel to be retracted again. Various programs can be selected for operating the towel dispenser, and in particular the loop can be formed from unused and used towel or only from unused towel.

Description

The invention relates to a towel dispenser according to the preamble of claim 1.

Towel dispensers of the generic type are known (CH-A-0 560 536, CH-A-0 561 535), in which a section after being triggered by a device to be operated by the user, such as a light barrier, a proximity or touch switch or a push button unused cloth and released after a certain period of time as a used cloth without checking whether it has actually been used or not. Such towel dispensers only offer the possibility of a program which runs after being triggered without taking account of external processes, which, among other disadvantages, often leads to wasted clean cloth, in particular due to incorrect triggering, so that the cloth web has to be washed more frequently. However, for both economic and ecological reasons, it is desirable to use a clean cloth as sparingly as possible and to avoid unnecessarily shortening the washing cycles.

Mechanical towel dispensers are also known (EP-A-0 283 554), in which unused towel is pulled out of a housing by the user and thereby a spring motor is tensioned, through which used towel is drawn in after a fixed period of time. Actual false triggers are excluded in this proven system, but the requirements for flexible adaptation of the program to external circumstances, in particular the period of use, are not met, for example can lead to unnecessary waiting times when there is a large crowd.

The invention seeks to remedy this. The invention, as characterized in the claims, creates a towel dispenser that registers usage, etc. and can thereby flexibly adapt to external circumstances. In particular, the prerequisites for pulling in the already released cloth after it has not been used are also given, and thus the possibility of extremely economical use of clean cloth, although the cloth is released electrically and the user is not required to mechanically actuate the device. There are many options for choosing the trigger mechanism.

The advantages of the invention can also be seen in the fact that it opens up many possibilities for responding to special operating conditions with special programs that can be selected by the maintenance and installation staff or the operator. A program can even support the replacement of used with unused cloth webs, thereby simplifying and accelerating them.

Fig. 1

einen Draufblick auf die rechte Seite eines erfindungsgemässen Handtuchspenders mit eingelegtem Tuch, wobei die Seitenwand weggelassen ist,

Fig. 2

eine Vorderansicht des Handtuchspenders, wobei ein vorderer Deckel weggelassen ist,

Fig. 3

einen Draufblick auf die rechte Seitenwand des Handtuchspenders, wobei ein seitlicher Deckel weggelassen ist,

Fig. 4

vergrössert einen einen Bewegungssensor darstellenden Ausschnitt aus Fig. 1,

Fig. 5

eine zum Bewegungssensor gehörende Schaltung,

Fig. 6

ein Flussdiagramm, das ein Verfahren zum Betrieb des erfindungsgemässen Handtuchspenders veranschaulicht, wobei vor allem die in einem Ruhezustand durchlaufenen Teile im Detail dargestellt sind,

Fig. 7a

ein Flussdiagramm, das im Detail die nach einer Auslösung bei einem Standardprogramm durchlaufenen Schritte zeigt,

Fig. 7b

ein Flussdiagramm, das im Detail die nach einer Auslösung bei einem speziellen Hygieneprogramm durchlaufenen Schritte zeigt, und

Fig. 8

ein weiteres Flussdiagramm, das das Feststellen einer Benutzung des Handtuchs im einzelnen darstellt.

In the following, the invention will be explained in more detail with reference to figures that represent only one exemplary embodiment. Show it

Fig. 1

a top view of the right side of a towel dispenser according to the invention with an inserted towel, the side wall being omitted,

Fig. 2

2 shows a front view of the towel dispenser, with a front cover being omitted,

Fig. 3

a top view of the right side wall of the Towel dispenser, with a side cover omitted,

Fig. 4

1 enlarges a detail from FIG. 1 representing a motion sensor,

Fig. 5

a circuit belonging to the motion sensor,

Fig. 6

2 shows a flowchart which illustrates a method for operating the towel dispenser according to the invention, in particular the parts which have been passed through in a rest state are shown in detail,

Fig. 7a

1 shows a flowchart which shows in detail the steps carried out after a triggering in a standard program,

Fig. 7b

a flow chart showing in detail the steps carried out after a trigger in a special hygiene program, and

Fig. 8

another flowchart detailing the use of the towel.

In Figures 1 to 5, a towel dispenser according to the invention is shown, which in a housing 1, which is mounted with its rear wall 2 on a wall, a tiltable, suspended by springs 3 with an upward force 4 for receiving a to Roll unused cloth web 5 (shown in dashed lines) and a first transport device with a transport roller 6a covered with nubbed rubber, which consists of a worm gear consisting of a worm 7a and a worm gear gear 8a connected to the transport roller 6a is driven by an electric motor 9a. A half disk 10a attached to the screw 7a forms a revolution counter with a stationary light barrier 11a which detects passages of the half disk 10a. The gear 8a is connected to the transport roller 6a via a slip clutch, which responds when a tensile force of more than 4 kp acts on the cloth 5. The cloth 5 is pressed against the transport roller 6a by a spring-loaded pressure plate 12. A second drive device is constructed analogously to the first, with a transport roller 6b, a worm gear with worm 7b, gear 8b and electric motor 9b, and a revolution counter with a half disk 10b and a light barrier 11b. A roller 13 is guided in grooves 14a, b in side walls 15a, b of the housing 1 for receiving used cloth. To the front, the housing is closed by a cover 16, which is secured by a lock, so that it can only be opened by authorized personnel for maintenance purposes, in particular for changing the cloth. On the side, the housing 1 has a cover 17a, b. The power supply of the device is ensured by a power supply 18.

According to the invention, the towel dispenser has a central control unit 19 which processes the signals from various sensors and in particular controls the transport devices. In order to determine movements of the cloth 5 caused by external action, the towel dispenser has a motion sensor 20 with a bracket 22 which is rotatably suspended in a sensor housing 21 and at the lower end of which a bar 23 projects horizontally, over the front end of which the cloth 5 by means of a deflection strip 24 is guided in such a way that it exerts a force on it due to its own weight even in the untensioned state. The bracket 22 is suspended in such a way that a restoring force occurs during deflections, which ensures that that it is only slightly deflected from its vertical rest position by the forces exerted on it by the cloth 5 at rest. With larger forces transmitted through the cloth 5, stops 25a, b limit the deflection. In a rectangular recess of the bracket 22 there is a piezo element 26 formed as a rectangular strip, which is firmly clamped into the bracket 22 with a first contact area at its upper edge and at a second contact area near its lower end between one in the sensor housing 21 screwed threaded bolt 27 and with the same coaxial also attached to the sensor housing 21 coil spring 28 is clamped. The threaded bolt can be adjusted by rotating perpendicular to the plane of the piezo element 26. Since the elastic piezo element 26 provides at least part of the restoring force for the bracket 22, the zero position of the bracket 22 can be adjusted in this way. The output signal of the piezo element 26 is processed in the circuit shown in FIG. 5, which essentially represents a limit value detector. At a constant bending moment, the piezo element 26 is electrically inactive. Changes in the bending moment, which are caused by movements of the bracket 22 caused by external influences on the cloth 5, cause a current surge. Practice has shown that a change in the bending moment in one direction always leads to a very rapid change in the opposite direction, so that current surges of different signs always follow one another quickly, of which consequently only one needs to be detected. The piezo element 26 is connected in parallel with the derivation of the current surge resistors 29a, b, of which 29b can be adjusted to adjust the voltage generated by the piezo element 26, between a first voltage divider 30a and and the negative input of a comparator 31, at the positive input of which the Exit of a second Voltage divider 30b is. The voltage dividers are connected to a supply voltage of + 5 V and are designed such that the output voltage of the second voltage divider 30b is slightly lower than that of the first voltage divider 30a, so that the output of the comparator 31 is normally at zero. If a sufficiently strong voltage surge of negative polarity caused by the piezo element 26 is superimposed on the output voltage of the first voltage divider 30a, the voltage at the negative input of the comparator 31 drops below the output voltage of the second voltage divider 30b present at the positive input, so that the output signal of the comparator 31 is on One jumps.

An infrared sensor 32 monitors the space sector below to obliquely below the towel dispenser for heat-radiating objects.

A rotatably suspended flap 33, around which the cloth 5 is guided, is connected to a lever 34 which actuates a microswitch 35 when the cloth 5 is fully tensioned and presses the flap 33 all the way up. Another lever 36 interacts with another microswitch 37. The lever 36 actuates the microswitch 37 when the lock (not shown) is locked. Locking the lock is only possible when the cover 16 is closed.

Between the shell 4 and the transport roller 6a, the cloth 5 is guided over a roller 38 which has three circumferential grooves 39a, b, c. A button 40 which is rotatably suspended on an axis parallel to the roller 38 has three fingers 41a, b, c which are pressed against the grooves 39a, b, c under the influence of the spring force acting on the button 40. When the cloth end passes the roller 38, the fingers 41a, b, c can reach the bottom of the grooves 39a, b, c are pressed and the button 40 rotates counterclockwise. As a result, a lever 42 connected to it actuates a microswitch 44 via a lifting rod 43. A further microswitch 45 detects actuations of a jump start button 46. All sensors and microswitches are connected to the control unit 19.

A plug 47 is used to connect the towel dispenser to a second towel dispenser of the same type, which is normally attached next to it.

The method for operating the towel dispenser according to the invention is explained below with reference to FIGS. 6 to 8.

At AA in FIG. 6, the control unit 19 is initialized, for example after the towel dispenser has been switched on, whereupon it carries out various initializations and checks of further elements. After completion of these processes, the microswitch 37 is queried in AB, i. H. determined whether the lid 16 is closed and locked. In the negative, it is assumed that a fresh sheet of fabric is loaded and control passes to an AC sheet loading program.

The cloth change is carried out by first pulling the roll 13, on which the used cloth is wound, forward out of the grooves 14a, b after the cover 16 has been completely opened, then tilting the tray 4 downward and placing the fresh roll of cloth in it and then the cloth 5 between the roller 38 and the button 40 through and then pulled over the transport roller 6a. Then the starter button 46 is actuated, which causes the release of approximately 1.3 m of cloth by the first transport device. The cloth end is then wrapped around a new roll 13 and the same around the motion sensor 20 and Flap 33 moved around and inserted with its ends into the grooves 14a, b until it or the cloth wound on it touches the transport roller 6b. The flap 33 is then pushed upwards and the cover 16 is closed and blocked, which is registered by the microswitch 37 and triggers a complete retraction of the cloth 5 except for a remnant of cloth by the second transport device. The control unit 19 is informed by the microswitch 35 that the cloth 5 is completely drawn in, that is to say it is tensioned, whereupon it stops the electric motor 9b. This concludes the AC cloth loading program and control passes to AD. If it is determined in AB that the cover 16 is closed and blocked, control passes directly to AD. The state of the microswitch 44 is queried in AD and it is determined whether the cloth end has been reached or whether fresh cloth is still in stock. If the cloth end is reached, a control lamp on housing 1 lights up and the control goes back to AB. As a result, it is only checked periodically whether the cover 16 is closed and blocked or open.

If cloth is still present, AE checks which release mechanism has been selected for the release of the cloth. There are two possibilities: the triggering can be carried out by the infrared sensor 32, which indicates when a person who is likely to use the towel dispenser is approaching or by the motion sensor 20, which registers movements of the towel 5. In the first case, control passes to AF, where it is determined by means of the microswitch 35 whether the cloth 5 is stretched. In the negative, the second transport device is activated in AG until the periodic check gives a positive result. In this case - regardless of the positive result from the start - the program continues with AH, where it is checked whether the infrared sensor 20 responds. If not, it works Check back at AB. If triggering by the motion sensor 20 has been selected, which is particularly recommended in order to avoid false triggering in confined spaces, the control changes from AE to AI, where it is checked in the manner explained above whether the motion sensor 20 is touching the cloth displays. To enable this type of triggering, a piece of cloth of 8 cm in length is released by the first transport device each time after the cloth 5 has been tensioned, so that the accessible cloth remnant forms a short loop that the user can grasp.

At rest, d. that is, as long as there is no triggering, the program parts described so far are run through periodically. When triggered, regardless of whether by the infrared sensor 32 or by the motion sensor 20, control passes to AJ, where it is queried whether the towel dispenser is to be operated according to a standard program AK or according to a hygiene program AL. After executing one of these programs, you will return to AB.

The standard program AK shown in detail in FIG. 7a begins with step AM, where normally 32 cm of unused cloth is released by the first transport device. However, you can choose a savings program with the release of 27 cm cloth. The length of the released cloth section is checked using the revolution counter. One turn of the screw 7a corresponds to approximately 3 mm of cloth. Subsequently, 15 cm of used cloth is released in AN by the second transport device, and 10 cm in the savings program. So that the front of the loop consists exclusively of unused cloth, less used than unused cloth is dispensed. The length control is carried out as for the unused cloth. The issue of used cloth has the advantage of saving fresh cloth At the same time maintaining user comfort by providing a sufficiently large loop. The user will normally not touch the rear part of the loop and therefore will not come into contact with the cloth used by his predecessor.

In the next step AO, it is determined by means of the motion sensor 20 whether the released cloth has been used or not. This review will be explained in detail below. If no use is found, the released unused cloth is completely withdrawn in AP. Of course, this step offers great savings potential, since it is very easy for false tripping by people walking past the towel dispenser, especially when triggered by an infrared or other proximity sensor. Such trips without subsequent use in the process according to the standard program result in no waste of unused cloth. In the following step AQ, cloth is drawn in by the second transport device until it is completely stretched and only a remnant of cloth is accessible.

If usage is determined in AO, it is first checked in AR whether the towel dispenser is operated according to a normal program or a quick program. In the latter case, unused cloth is released in AS - again normally 32 cm, with savings program 27 cm - and then drawn into used 32 cm or 27 cm used cloth, whereupon you return to AO. The quick program therefore dispenses unused cloth, not only before the used cloth is drawn in, but also without waiting for it to be triggered. This is only possible without wasting cloth because it is monitored whether use is taking place and the unused cloth is pulled back when not in use, which is then followed by the Is taken into hibernation. Choosing the quick program is particularly advisable when large crowds are expected.

If the normal program has been selected, the used cloth is pulled into AU as far as it will go, just like in AQ. The trigger mechanism is queried in AV. When triggered by the infrared sensor 20, the standard program AK is left and AB, d. H. returned to the idle state. When triggered by the motion sensor 20, 8 cm of unused cloth are released beforehand in AW to form a short loop.

In addition to the standard program AK, a hygiene program AL is offered, which is specially designed for the use of the towel dispenser according to the invention in hospitals and other particularly high demands on the hygienic environment such as. B. Food production companies, laboratories, etc. was developed. Particular emphasis was placed on ensuring that a user can never come into contact with a section of cloth that has been touched by another user. Only fresh, unused cloth is made available to every user. In addition, a slightly longer section of cloth is made available than in the standard program.

64 cm of unused cloth is normally released in AX. However, a savings program is also available here, in which only a 54 cm long section is released. In AY, 17 cm are then drawn in by the second transport device, thereby making the remainder of the cloth that was accessible before being released inaccessible. At AZ it is determined whether a use has been made. In the negative, in BA 41 cm or - in the austerity program - 31 cm are withdrawn again and then in BB pulled in the cloth on the feed side until it stops. The saving by retracting the unused cloth when not in use is also considerable here, although there is no complete retraction. If no use is found in AZ, only in BC the cloth is pulled in as far as it will in BB. In any case, control passes to BD, where the trigger mode is queried. Analogous to the standard program AK, when triggered by the infrared sensor 32, the system jumps back immediately to AB, when triggered by the motion sensor 20, 8 cm of unused cloth are released beforehand in BE, so that the accessible cloth remnant forms a small loop.

It should also be mentioned that since the shell 4 is usually pulled down through the cloth 5 when unused cloth is released, the release to protect the springs 3 is always carried out in such a way that an additional 2 cm of cloth is dispensed and immediately pulled back in again. This enables the shell 4 to be pulled up.

The determination of a use which is carried out both in the standard program AK (step AO) and in the hygiene program AL (step AZ) is now explained with reference to FIG. 8. In BF a timer is set with a runtime of 20 sec. BG checks whether the movement sensor 20 has detected a movement imprinted on the cloth. If not, the BH checks whether the timer is still set. If so, there is a jump back to BG, otherwise it is determined that no use has been made. If it is determined in BG that the cloth is being moved, then a further timer with a 3 sec running time is set in BI and then again checked in BJ whether the movement sensor 20 has detected a movement. If so, the system jumps back to BI, ie the timer is reset to the start of the runtime. Will not be in BJ Movement of the cloth is detected, BK checks whether the timer is still set. If so, the system returns to BJ, otherwise use is determined. The loops BG-BH-BG and BJ-BK-BJ are run through 64000 times per second. Since the voltage pulses generated by the piezo element 26 last at least a few milliseconds, any movement beyond an adjustable threshold is detected with certainty.

If, after formation of the loop, the cloth 5 is not touched for a standby time of 20 seconds, no use is determined and the released unused cloth 5 is withdrawn completely (standard program AK) or partially (hygiene program AL). If the cloth 5 is touched, it is checked whether the loop is touched until no movement has been detected for a waiting time of 3 seconds. So the user has any amount of time to use the cloth. Only when he has not touched it for at least 3 seconds is it determined that use has been made and is complete and the next step has been initiated.

When it has been determined in AD that the towel 5 has been used up, an adjacent, similar towel dispenser can be activated by means of the plug 47, and various program parameters can also be transmitted, so that the second towel dispenser functions exactly the same as the first (standard / hygiene program, etc. ).

It is also possible to provide information transfer between towel dispensers and a control center either via the power line or via separate lines. Information about the condition of the towel dispenser, in particular the supply of towels, can be sent to the central and vice versa commands, e.g. B. for program switching to the Towel dispenser can be transferred.

Claims (12)

1. Towel dispenser for the sequential provision of portions of a towel web (5), with a first electrically driven transport device for unused towel and a second electrically driven transport device for used towel, in a housing (1) with at least one orifice for making accessible a towel portion located between the first transport device and the second transport device and with a central control unit (19) for controlling the transport devices and with a touch-contact element, via which the towel web (5) is guided between the first transport device and the second transport device, in such a way that, even in the non-tensioned state, as a result of its own weight it exerts a force on the said element, characterised in that it has a movement sensor (20) connected to the central control unit for indicating movements transferred from the accessible towel portion during acts of use to the touch-contact element, the movement sensor (20) responding to changes in position of the touch-contact element.
2. Towel dispenser according to Claim 1, characterised in that the movement sensor (20) contains a piezoelectric element (26) which is in at least indirect mechanical contact, on a first contact region, with the touch-contact element and, on a second contact region, with the housing (1) respectively.
3. Towel dispenser according to Claim 2, characterised in that the touch-contact element is designed as a batten (23) projecting from a bar (22) suspended rotatably about a horizontal axis, at the lower end of the latter, and the piezoelectric element (26) is designed as a strip fastened with its first contact region to the bar (22) and clamped with its second contact region between a clamping piece and a spring which are both connected at least indirectly to the housing (1).
4. Towel dispenser according to Claim 3, characterised in that the clamping piece is designed as a threaded bolt (27) adjustable perpendicularly to the plane of the piezoelectric element (26) as a result of rotation about its axis, and the spring is designed as a helical spring (28) coaxial with the threaded bolt (27).
5. Towel dispenser according to one of Claims 2 to 4, characterised in that the piezoelectric element (26) is connected in parallel with a resistor (29a, 29b) between a first voltage divider (30a) and one input of a comparator (31), the second input of which is preceded by a second voltage divider (30b), the output voltage of which differs from that of the first voltage divider (30a) by between 0.1 V and 1 V.
6. Towel dispenser according to Claim 5, characterised in that the resistor (29b) can be regulated.
7. Towel dispenser according to one of Claims 1 to 6, characterised in that it has a proximity sensor for detecting objects located underneath or obliquely underneath the towel dispenser.
8. Towel dispenser according to one of Claims 1 to 7, characterised in that the first transport device and the second transport device each contain a transport roller (6a; 6b), via which the towel web (5) is guided, as well as an electric motor (9a; 9b) and a worm gear, via which the latter is connected to the transport roller (6a; 6b).
9. Towel dispenser according to Claim 8, characterised in that the transport roller (6a; 6b) is connected to the electric motor (9a; 9b) via a respective slip coupling.
10. Towel dispenser according to Claim 8 or 9, characterised in that each of the transport devices has a revolution counter which is connected to the control unit (19).
11. Towel dispenser according to Claim 10, characterised in that the revolution counter contains respectively an interrupted circular disc attached to a movable part of the particular transport device as well as a fixed light barrier (11a; 11b), through the sensing range of which the circular disc is moved.
12. Towel dispenser according to one of Claims 1 to 11, characterised in that it has a towel-end feeler with a roller (38), via which the towel web (5) is guided and which is provided with at least one continuous groove (39a, 39b, 39c), as well as with at least one finger (41a, 41b, 41c) suspended rotatably on an axle parallel to the roller (38) and pressing against the groove, and with a lever (42) which is connected to the axle and which actuates a microswitch (44) connected to the control unit (19), if the at least one finger (41a, 41b, 41c) reaches the bottom of the at least one groove (39a, 39b, 39c).

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