EP0994667A1

EP0994667A1 - Towel dispenser

Info

Publication number: EP0994667A1
Application number: EP99924956A
Authority: EP
Inventors: Michael STÜTZEL; Andreas Heub-Schneider
Original assignee: Blatz Wilhem
Current assignee: Blatz Wilhem
Priority date: 1998-05-12
Filing date: 1999-05-12
Publication date: 2000-04-26
Anticipated expiration: 2019-05-12
Also published as: EP0994667B1; AU4142799A; DE19820978A1; DE19980817D2; DE59904822D1; HK1028717A1; ES2196810T3; ZA200000068B; CA2294820A1; WO1999058040A1; ATE235853T1; US6412655B1

Abstract

The invention relates to a towel dispenser (10) such as a paper towel dispenser comprising a housing (12) in which a paper roll and an issuing device (50) are arranged. Said issuing device can AC be controlled by a sensor (38). In order to simplify the operation and to increase the reliability of the towel dispenser, the invention provides that the sensor (38) is configured as a capacitive sensor.

Description

description

Towel dispenser

The invention relates to a towel dispenser, in particular paper towel dispenser, comprising a housing in which a receptacle such as a roll for the towel or several towels and an output device for this or these are provided, the output device being actuable via a sensor which can be activated by the housing exterior . Furthermore, the invention relates to a towel dispenser, in particular paper towel dispenser, comprising a housing in which, on the one hand, the dispenser item, such as. B. a paper roll and on the other hand an output device are arranged.

Towel and in particular paper towel dispensers are known, the dispenser of which responds to a light-sensitive sensor. To prevent the sensor from reacting to changes in light, e.g. B. caused by people walking by, the sensor must be arranged in the known dispenser devices on a side housing wall, so that defined lighting conditions are guaranteed. However, this has the disadvantage that operators only recognize the laterally arranged sensor after a long search. Such dispensing devices are also often arranged too close to the side walls, so that the amount of light is not sufficient to trigger a safe switching operation. 2

A paper towel dispenser can be found in US Pat. No. 4,406,421, from the housing exterior of which a lever is accessible, via which the toothed rack and pinion running inside the housing mesh in such a way that a section of the paper towel is accessible via a dispensing opening.

WO 97/29671 describes an electrically operable paper towel dispenser which can be actuated by means of a photo sensor.

In order to be able to remove liquid soap from a dispenser, particularly in the area of operating theaters, without touching it directly, a capacitive sensor is used according to DE 34 00 575 AI, one electrode of which runs directly in the area of the liquid dispensing opening. The counter electrode forms the footprint of the person who wants to use the dispenser.

The present invention is based on the problem of developing a dispenser device of the type mentioned at the outset in such a way that its operation is simplified and the reliability is increased.

According to the invention, the problem is essentially solved in that the sensor is a capacitive sensor with a first flat and a second flat electrode, which are arranged inside the housing and run along at least one housing wall. In particular, it is provided that the first and second electrodes run in one plane or in two planes which run parallel or approximately parallel to a housing wall, in particular to the housing front wall. The electrodes should have planar deviations that differ from one another, in particular in a ratio of 1: 5 to 1:20, in particular 1:10. B. 8 cm ² and the other electrode have an area of 0.8 cm ² .

In particular, it is provided that the electrodes are at a distance from one another which is equal to or less than the narrower electrode, which can also be referred to as a strip. 3 trode is in its width extension. The electrodes themselves should have a capacitance of approximately 1 pF ± 0.25 pF in the idle state, that is, when there is only air as the dielectric outside the housing. If the dielectric then changes due to an approaching hand, a signal is triggered by the change in capacitance, which in turn actuates the towel dispenser. The electrodes forming the capacitor and running in one plane or possibly two parallel planes, i.e. offset with respect to one another, produce a quasi-directed field in such a way that the capacitance is influenced when the dielectric distance changes by up to approximately 30 mm to the surface of the towel dispenser housing through z. B. Approaching one hand. The capacitor formed by the electrodes running in one plane can be referred to as an open plate capacitor.

The capacitive sensor creates an electric field in its environment, which is changed by the approach of a human hand. The change is evaluated and triggers a pulse to actuate the output device. The dispenser device can thus be used regardless of room-related lighting conditions or other environmental influences.

It is also only necessary to trigger the output device that the electrical field running between the electrodes somehow to the required extent z. B. is changed by approaching a hand without specifically touching a particular point of the housing or a hand must remain in a very specific area. It is also functional in rooms where there is a high level of dirt or high relative humidity.

In a particularly preferred embodiment it is provided that the sensor is arranged on the housing front side directly behind a front side of the housing. The disposition of the sensor on the front ensures easy operation of the dispenser. Arranging on another side or aligning one electrode at a time on a separate housing side is also possible, provided an effective and influenceable field spreads outside the housing.

In a further preferred embodiment of the dispenser device, it is provided that the front of the housing has at least one visualization for pointing to a sensor area and / or to a removal opening. It is provided that the visualization on the front of the housing is designed as at least two indentations running in the horizontal direction. The indentations are preferably designed as semicircular, relief-like grooves. It is also proposed that the indentations divide the front of the housing in the ratio of the golden ratio.

Regardless of the visualization of the removal or localization of the sensor field or the sensor surface, the stiffness of the housing surface is increased by the indentations.

The sensitivity of the capacitive sensor can be adjusted in order to rule out malfunctions of the dispenser device. In order to make the sensor as simple as possible, it is proposed that it have a first, preferably flat, electrode and a counterelectrode, both of which are arranged directly behind a front surface of the front, in order to create an electrical field outside the housing

In order to ensure mains-independent operation of the dispenser device, it is equipped with a battery-operated drive device.

For simple maintenance and operation, a button is arranged on the inside of the housing, by means of which the output device can be controlled when the housing is open. A timer is also provided, by means of which the activation time of the output device can be set. 5

An integrated dead time element is also provided for determining a time after which the output device can be actuated again. The circuit arrangement has overcurrent protection as overload protection for a motor driving the output device.

In a mechanical embodiment of the dispensing device, a spring-loaded lever that can be operated from the front of the housing and has a toothed rack for driving the dispensing device is provided. The rack follows a circular section whose center is the axis of rotation of the lever.

For dispensing paper towels in the form of paper rolls but also in the form of individual towels, it is provided that the dispensing device consists of a pull roller and a pressure roller arranged opposite it, the rack interacting with a gear wheel arranged on the shaft of the pull roller. The gear is designed with a sleeve freewheel.

In the electrical embodiment of the dispenser device, a motor is provided with an associated gear, which engages in the gearwheel arranged on the shaft of the pulling roller. The motor is controlled by the sensor-driven control unit.

In particular in the case of an embodiment as a paper towel dispenser, in which the paper towels are unwound from a paper roll, a separating device is provided, the separating device being arranged on the inside of the housing and not being accessible from the outside. In this, the embodiment according to the invention differs from the prior art, because in known devices the separating device is arranged on the front of the housing, which means that injuries are possible when reaching for paper towels or when separating the paper towels.

Regardless of whether the dispenser device is operated electrically or mechanically 6, the housing has a number of advantages over housings known from the prior art. In a particularly preferred embodiment, it is provided that an upper side of the housing is inclined toward the viewer by approximately 8 ° with respect to the horizontal, so that the placement of rolling objects such as cigarettes is excluded.

An intermediate field inclined towards the mounting wall is also provided between the top and the front. Furthermore, at least one side wall of the housing viewing window is arranged to observe the donated goods. The housing is preferably made entirely of plastic.

Further details, advantages and features of the invention result not only from the claims, the features to be extracted from them - individually and / or in combination - but also from the following description of an exemplary embodiment which can be found in the drawing.

Show it:

1 is a perspective view of a towel dispenser,

2 shows a sectional illustration of the dispenser device according to FIG. 1 in an electrical embodiment,

3 shows a block diagram of a control circuit for the dispenser device according to FIG. 9

Fig. 4 is a sectional view of the dispenser device of FIG. 1 in a mechanical embodiment and

Fig. 5 top view of electrodes of a capacitive sensor. 7

1 shows a perspective illustration of a sensor-operated electrical dispenser device 10 in the form of a paper towel dispenser with an integrated paper roll.

The dispenser device 10 has a housing 12 which consists of a hood-shaped cover 14 and a rear wall 16 which can be fastened to a mounting wall (not shown). The cover 14 is pivotally attached to the rear wall 16.

The hood-shaped cover 14 comprises an upper side 18, a front side 20, a lower side 22 and side surfaces 24, 26. Overall, the surface of the hood-shaped cover 14 is closed, smooth and shiny, the individual sides 18, 20, 22 being at different angles to one another , so that there is a characteristic, dynamic appearance.

In particular, the upper side 18 is inclined slightly towards the viewer, preferably at an angle of approximately 8 °, so that cigarettes and similar rolling objects are prevented from being put down or left lying. Between the top 18 and the front 20, a transition area 28 or intermediate field is provided, which is inclined towards the mounting wall. so that the optical alignment of the hood-shaped cover 14 is directed towards a removal opening 30 arranged in the lower region of the front side 20 for paper removal.

The housing 12 shown in FIG. 1 is a housing for an electrically operated dispenser device with sensor activation. To visualize the removal opening 30 and to locate a sensor field 31, two protrusions 32, 34 running in the horizontal direction are molded into the front 20 of the cover 14. These are semi-circular, relief-like grooves. These divide the dispenser housing 12 in the ratio of the golden ratio, so that there is a balanced appearance. The grooves 32, 34 which are semicircular in cross section have a radius which is selected such that a 8 flawless cleaning of the housing surface is guaranteed. In addition to the informative character of the formations 32, 34 such as grooves, these also increase the component rigidity, in particular of the front side 20.

In order to avoid a direct view into the removal opening 30, a housing surface section 36, into which the removal opening 30 is introduced, is also inclined towards the mounting wall (not shown).

In both side walls 24, 26 of the hood-shaped cover 14, viewing windows 38 are arranged which, by means of an indicated arrow shape, enable the amount of unused towels present in the housing 12 to be checked. The viewing windows are made of transparent plastic and divided into two (erosion structure / without structure), with a control mark based on the contour of the towel supply and the paper roll.

The rear wall 16 is completely surrounded by the hood-shaped cover 14, so that it is not visible in the assembled state. A circumferential edge (not shown) on the rear of the dispenser provides a distance of approximately 2.5 mm from the mounting wall, so that splash water, condensation, etc. run off unhindered and cannot penetrate into the dispenser 10.

FIG. 2 shows a cross section of the electrically operated dispenser device 10 according to FIG. 1. Compared to conventional dispensing devices, the dispensing device 10 according to the invention is characterized in that it has a capacitive sensor 38, which is arranged directly behind the front side 20 in the exemplary embodiment. In particular, the capacitive sensor 38 has a flat electrode 40 and a counter electrode 42, which are arranged behind a sensor field 31 which is particularly emphasized on the front side by the horizontally running grooves 32 and 34. The arrangement of the capacitive sensor 38 on the front makes it much more user-friendly than the dispenser devices known from the prior art 9

Handling possible since the sensor does not necessarily have to be arranged on the side. The electrodes 40, 42 extend at least in regions parallel or approximately parallel to the sensor field 31. The sensor field 31 can encompass the entire width of the housing.

The sensor field can also run in the region of the abutting front and side surfaces 20, 26 of the housing 10 than in the region of an edge of the housing 10.

The capacitive sensor 38 is connected to an evaluation circuit arranged on a circuit board 44, which is described in more detail in FIG. 3.

Starting from the rear wall 16, a holder 46 is provided which carries a roller 48 for receiving a towel roll, in particular a paper roll (not shown). An output device 50 is provided for outputting a portion of the roll from the removal opening 30.

The dispensing device 50 comprises a pulling roller 54 arranged on a shaft 52 and a pressure roller 58 also arranged opposite on a shaft 56. A paper strip (not shown) to be transported is introduced into a gap 60 formed between the pull roller 54 and the pressure roller 58 and is conveyed outward through the removal opening 30 when the pull roller 54 is driven.

To cut off the paper, a cutting edge 62 is provided, which in the exemplary embodiment shown here is designed as a Z-shaped angle profile made of sheet metal with a tooth pattern. The teeth attached to a longitudinal edge of the cutting edge are preferably of different lengths.

The transported paper strip is guided along an arcuate guide surface 34 in the direction of the removal opening 30. 10

In the exemplary embodiment shown here according to FIG. 2, the torque is transmitted by means of a motor 66 which can be controlled via the control electronics 44. On the output side, the motor 66 has a gearwheel 68 which interacts via a further gearwheel 70 with a gearwheel 72 arranged on the shaft 52 of the tension roller 54.

Furthermore, an energy supply 74 is provided, which can be battery-operated as well as mains-operated.

In connection with the arrangement of the cutting edge 62 or tear-off edge, it should be noted that this is arranged on the inside of the housing, so that contact with the cutting edge 62 is excluded or at least largely excluded when the removal opening 30 engages.

3 shows a block diagram of a sensor-controlled motor control 76. The motor controller 76 has an energy supply unit 78, with a transformer 80 and a first supply unit 82 for the energy supply of the sensor 38 and a second supply unit 84 for the energy supply of the motor 66.

The capacitive sensor 38 consists of the first flat electrode 40 and the counter electrode 42 for generating an electric field. The sensor 38 is connected to an electronic control unit 88, which in turn is connected to a motor control circuit 90, which receives its energy from the second supply unit 84.

The electronic control unit 88 is also connected to a trimmer 92, which is used to set a drive time of the motor 66, which directly determines the paper length. Furthermore, a button 94 is provided which enables the motor 66 to be controlled manually when the cover 14 is used when changing the paper 1 1 is open. Overall, the control of the motor 66 is only possible when the cover 14 is closed. The closed position of the housing or the hood-shaped cover 14 is detected by a switch 96.

The motor controller 90 directly controls the motor 66, which controls the output device 50 via a gear 98 having the gears 68, 70. With regard to the functioning of the motor control 76, it should be noted that the proximity of one hand changes the electrical field formed between the electrodes 40 and 42, in particular the dielectric constant of the dielectric otherwise formed by air, and that the change is detected by the electronic control unit 88 and becomes a control signal is processed. In accordance with the actuation time set by the trimmer 92, the motor 66 is actuated for a specific period of time, so that a paper strip of a predetermined length is dispensed.

All components of the control circuit 76 are implemented in SMD technology. The complete circuit including the electrodes 40, 42 is also arranged on a circuit board. It should be mentioned as particularly advantageous that the printed circuit board 44, the electrodes 40 and 42 are arranged in the interior of the housing 12 and thus are not visible and not accessible from the outside. The control circuit 76 with the electrodes 40, 42 can also be arranged in a separate housing, as a result of which additional protection and, in the event of a fault, ease of maintenance are provided; In the event of an electronic circuit malfunction, the housing only has to be removed and replaced by a new, functional unit.

In order to specify a trigger lock for repeated activation, an integrated dead time element is provided, the dead time also being adjustable by means of a trimmer. An overcurrent protection circuit is also provided so that when the motor is blocked, the electronics are secured against excessive current, for example by a paper jam or due to blockage. 12

As can be seen from FIG. 5, the electrodes 40, 42 are approximately rectangular in shape and have area ratios of preferably 1:10. Thus, one of the electrodes - in the exemplary embodiment electrode 40 - can have an area of 8 cm ² and the other electrode 42 can have an area of 0.8 cm ² . The capacitor formed by the electrodes 40, 42 should then - if the dielectric z. B. is not influenced by one hand, that is, in the idle state, have a capacitance of approximately 1 pF ± 0.25 pF. Then there is a change in the dielectric by z. B. Approach of a hand to the housing 12 and in particular the sensor surface 31, a change in capacitance is caused due to the change in the dielectric, which provide a switching process for dispensing a portion of the towel pulled off a roll, such as in particular paper towel.

As already shown in FIG. 5 without a detailed description, the electrode 40 is rectangular and the electrode 42 is strip-shaped, the electrodes 40, 42 being at a distance 41 which is smaller than the electrode 42 in its width. If a surface of a unit 1 is spanned by the electrodes 40, 42 including the distance 41, approximately 80% of it falls on the electrode 40, approximately 5% on the strip-shaped distance 41 and approximately on the strip-shaped electrode 42 15%. This creates the desired directed electric field extending to the exterior of the housing 12.

The formation of the electrodes 40, 42, in particular their different sizes and their arrangement in a plane that runs parallel to a housing wall, in particular to the front housing wall 20 or the sensor surface 31, generates a directed electrical field that extends to the housing exterior, which in the extent required to trigger a control command is influenced when z. B. a hand in the range up to 30 mm from the wall 20 or the surface 31 moved away without the need to directly touch the wall 20 or the sensor surface 31. 13

FIG. 4 shows a sectional illustration of a mechanically actuated dispenser device 100. It should be noted here that the shape of the housing 12 essentially corresponds to the shape of the electrically operated dispenser 10. In particular, the same output device 50 is used that has already been described with reference to FIG. 2.

According to the invention, a lever 102 is provided for the mechanical actuation of the output device 50, which lever is rotatably mounted in the interior of the housing 12 by an axis 104. A handle 106 is provided on the outside of the housing, which is connected to the lever arm 102 and can be moved essentially parallel to a surface 108 of the front side 20 of the housing 12 for actuating the lever 102. For the vertical movement of the lever arm 12, a slot-like, substantially vertical opening 110 is formed in the front side 20.

A rack 114 following an arc section is provided on an end 112 of the lever 102 opposite the axis 104, the arcuate rack 114 cooperating with the gear wheel 72 arranged on the shaft 52 and exerting a torque on the pull roller 54 when the lever 102 is actuated . The lever 102 is retracted into its starting position by means of a spring 116, which is designed, for example, as a torsion spring and is arranged coaxially with the axis. It is provided that the gear 72 is designed with a sleeve freewheel, so that when the lever or the curved rack 14 moves upward, no torque is transmitted from the sleeve freewheel to the pull roller 54.

The teachings according to the invention provide user-friendly and trouble-free towel dispensers. Service costs are reduced thanks to the ease of maintenance and the use of elements that are less subject to wear. Conversion from a mechanically to an electrically drivable paper dispenser and vice versa is also possible in a simple manner through the inventive design. 14

The housing 12 is preferably made of an impact-resistant, corrosion-resistant plastic, the stability of which is increased by edges and beads. By attaching an internal sensor according to the invention, external, fault-prone sensors can be dispensed with.

Claims

15 Claims Towel Dispenser

1. Towel dispenser (10, 100), in particular paper towel dispenser, comprising a housing (12) in which a receptacle such as a roll for the towel or several towels and an output device (50) for this or these are provided, the output device via a sensor (38) which can be activated from the housing exterior, characterized in that the sensor is a capacitive sensor (38) with a first and a second flat electrode (40, 42) which are arranged inside the housing (12) and along at least a housing wall (20).

2. Towel dispenser according to claim 1, characterized in that the first and second electrodes (40, 42) each run in one plane, preferably in a common plane, each parallel or approximately parallel to a housing wall, in particular to the housing front wall (20 ) runs. 16

3. Towel dispenser according to claim 1 or 2, characterized in that the electrodes (40, 42) have different planar extents, the areas of which behave approximately as 1: 5 to 1:20, in particular 1:10, and that the electrodes have a distance (41) which is preferably equal to or less than the narrower, strip-shaped electrode (42) in its width.

4. Towel dispenser according to at least one of the preceding claims, characterized in that the electrodes (40, 42) are arranged directly behind the one housing wall and extend at least in regions parallel or approximately parallel to a sensor surface (31) present in the housing wall, in Range of which an electric field extending between the electrodes can be influenced, in particular up to a distance a with a <30 mm.

5. Towel dispenser according to at least one of the preceding claims, characterized in that the sensor (28) is arranged directly behind the housing front wall or front (20) of the housing (12).

6. Towel dispenser according to at least one of the preceding claims, characterized in that the front (20) of the housing has at least one visualization (32, 34) for guidance to the sensor surface (31) and / or to a removal opening (30). 17

7. Towel dispenser according to one or more of the preceding claims, characterized in that the visualization on the front (20) of the housing (12) is designed as at least two indentations (32, 34) extending in the horizontal direction, in particular in the form of in cross section semicircular, relief-like grooves is formed, wherein preferably the indentations divide the front of the housing in the ratio of the golden ratio.

8. Towel dispenser according to one or more of the preceding claims, characterized in that the towel dispenser (10) is battery operated.

9. A towel dispenser according to one or more of the preceding claims, characterized in that the towel dispenser (10) has a button (94) on the inside of the housing, via which the dispenser (50) can be controlled when the housing is open.

10. Towel dispenser in the form of a paper towel dispenser with a separating device starting from the inside of the housing in the area of the dispensing device (50), according to one or more of the preceding claims, characterized in that the separating device (62) is inaccessible from the outside of the housing and that the separating device is parallel to Includes axis of rotation of the paper roll extending Z-shaped angle profile, the free longitudinal edge is designed as a tear-off edge with teeth that have different lengths. 18th

11. Towel dispenser according to one or more of the preceding claims, characterized in that the top (18) of the hood-shaped cover (14) is inclined towards the viewer by approximately 8 ° with respect to the horizontal.

12. Towel dispenser according to one or more of the preceding claims, characterized in that the side walls (24, 26) have viewing windows (38) for observing the dispensed goods.

13. Towel dispenser according to one or more of the preceding claims, characterized in that the housing parts consist of plastic, wherein the hood-shaped cover (14) is pivotally attached to the rear wall (16) and can be locked via a locking lock.

14. Towel dispenser according to one or more of the preceding claims, characterized in that the capacitive sensor (38) is adjustable with respect to its sensitivity and / or the output device (50) with respect to its activation time and / or the towel dispenser (10) Has dead time element for determining a time.

19

15. Towel dispenser (10, 100). in particular paper towel dispenser, comprising a housing (12) in which, on the one hand, the dispenser item, such as. B. a paper roll and on the other hand an output device (50) is arranged, characterized in that the towel dispenser (10, 100) can be controlled via a lever arm (102), the lever arm being operable from the front and spring-loaded and a rack (114) for driving of the output device (50), that the rack follows a circular section, the center of which forms a center of rotation (104) of the lever arm (102) and that the output device (50) consists of a pull roller (54) and a pressure roller (58) arranged opposite it The gear roller is assigned a gear wheel (72) which can be driven either by a motor (66) via a gear (98) or by the gear rack (114), the gear wheel (72) being driven by the gear rack (114). and the lever (108) is designed with a sleeve freewheel.

16. Towel dispenser according to at least one of the preceding claims, characterized in that the towel to the dispenser (50) runs through a gap (60) present between a pressure roller (58) and a tension roller (40), the tension roller via an electric drive ( 66) or the rack (114) is rotatable.