Background of the invention

The invention relates to a measuring arrangement for planar textile processing machines.

The invention further relates to a planar washing machine and to a method of detecting thickness of rugs and carpets in the washing machine.

The field of the invention is defined more specif ically in the preambles of the independent claims.

Planar washing machines have been developed for washing different kind of planar textile products. Such machines are used for example in self-service laundromats. The machines are provided with measuring systems configured to measure thicknesses of the textile products inside the machine. The present solutions have shown some disad vantages .

Brief description of the invention

An object of the invention is to provide a novel and improved measuring arrangement and a solution for de tecting thickness of a separate textile product being pro cessed in a planar textile treating machine.

The measuring arrangement according to the inven tion is characterized by the characterizing features of the first independent apparatus claim.

The planar washing machine according to the inven tion is characterized by the characterizing features of the second independent apparatus claim.

The method according to the invention is character ized by the characterizing features of the independent method claim.

An idea of the disclosed solution is that a textile processing machine is provided with an integrated measuring arrangement for detecting thickness of the processed tex tile product. The measuring arrangement comprises one or more sensing devices mounted in connection with a nip of a feed device, which is configured to feed the textile product through the nip. The nip is provided with a rotating support element and a rotating press roll between which is a gap for the textile product. The sensing device is configured to detect position of the press roll when the press roll is moved against the textile product. The detected position of the press roll is in proportion to the thickness of the textile product. In other words, the nip is utilized as a part of a thickness gauge.

An advantage of the disclosed solution is that ac curate quick thickness measurements can be provided. There is no need for any separate and complicated measuring sys tems in the machine, but instead the disclosed measuring means can be combined in connection with needed functional machine elements. Further, the structure of the measuring arrangement is simple, inexpensive and durable.

Let it be mentioned that the textile processing machine may be a planar washing machine or any other machine for treating planar textile products.

The nip in general means a gap between two feed elements, such as rolls arranged on opposite sides of the textile product so that the textile product is configured to be transferred through the nip. Typically the nip is in connection with a feed device and is needed to ensure proper feeding of the textile product.

According to an embodiment, the disclosed measuring arrangement is versatile and can be implemented in feed systems of different type of planar textile treating ma- chines. Further, the disclosed arrangement may also be ret rofitted to the existing machines easily in case they are already provided with feed devices with nips.

According to an embodiment, the mentioned rotating support element comprises at least two rotating support rolls and a rotating belt surrounding the support rolls. In other words, the nip is formed between a short belt system and the press roll which are arranged on opposite sides of the textile product. The press roll may be arranged to move centrally between the two support rolls of the belt system.

According to an embodiment, the rotating support element is alternatively a support roll. Then the nip com prises two rolls arranged on opposite sides of the textile product. There is a gap between two roll surfaces.

According to an embodiment, the press roll is sup ported to a pivot arm and is turnable between an upper idle position and a lower pressing position. The sensing device may be arranged to detect position of the pivot arm for detecting the thickness of the textile product. In other words, the sensing device senses movements of a moving mech anism of the press roll and not the press roll directly. The movement of the moving mechanism of the press roll may be detected by the sensor either directly or indirectly.

According to an embodiment, the arrangement com prises a sensing lever mechanism, which is a separate ele ment relative to a moving mechanism of the press roll. There is a transmission element in the sensing lever mechanism for transmitting movement of the moving mechanism of the press roll to the sensing lever mechanism. Thus, the sensing lever mechanism may move in accordance with the press roll system. Then the sensing device detects movement of the sensing lever mechanism. In other words, this solution im plements an indirect measuring principle, wherein position of the press roll and its moving mechanism is detected by detecting position of the separate sensing lever. The sens ing device or sensor is not in direct communication with the moving mechanism of the press roll.

According to an embodiment, the transmission ele ment is configured to transmit the movement of the moving mechanism of the press roll to the sensing lever mechanism only when the press roll is at its pressing position or is approaching it. This is logical since only the pressing phase and positions of the press roll when contacting an upper surface of the textile product are significant for the thickness sensing.

According to an embodiment, the transmission ele ment may be a roll, protrusion or other contact element. The roll may be arranged on a movement path of the pivot arm or corresponding moving mechanism of the press roll so that the pivot arm will collide the roll when approaching the pressing position. Then the roll transmits the movement to the sensing lever mechanism. According to an embodiment, the sensing lever mech anism comprises an angle lever provided with a first lever arm and a second lever arm in angled direction relative to each other. Further, there is a fulcrum allowing the angle lever to be pivoted relative to the fulcrum. The first lever arm is provided with the mentioned transmission element, such as a roll. The sensing device or sensor is configured to detect movement of the second lever arm. Distance between the transmission element and the fulcrum is shorter than distance between the sensing device and the fulcrum. The structure of the sensing lever is thereby eccentric. Thereby, movement of the angle lever appears in an exagger ated manner for the sensing device when compared to the movement of the transmission element. An advantage of this solution is that accurate sensing is possible when there is the disclosed transmission ratio between the movements. Small actual movement can cause relatively great movement to be sensed by the sensing device. This is a simple way to increase sensing accuracy. The transmission ratio may be for example 1:3, which means that when the first lever moves 1 mm the second lever moves 3 mm. Alternatively the ratio may be 1:5 or even greater.

According to an embodiment, the angle lever may be a right angle lever with eccentric fulcrum. There may be a roller at a distal end of the first lever arm and the sensing device may be arranged in close vicinity with a distal end of the second lever arm. In other words, the angle lever transmits different ratios of movement for the transmission element and the sensing device because they are located at different distances from the fulcrum.

According to an embodiment, the sensing device is a contactless sensor.

According to an embodiment, the sensing device is a contactless sensing device and is configured to send and receive sensing signals. The contact-free sensing device is configured to send detection signals towards the monitored object and the signals reflect back when they are detected. The sensing may also be based on magnetism. This way the arrangement utilizes non-contacting measurement principle. Thus, the thickness may be detected by using indirect remote sensing techniques. According to an embodiment, the sensing device is a contactless proximity sensor provided with a measuring range. The arrangement further comprises adjusting means for changing position of the sensing device whereby detec tion distance of the sensing device adjustable. The sensor may be supported to a side plate of the machine by means of support piece. The adjusting means are arranged to the sup port piece allowing the sensor to be moved relative to the immovable support piece.

According to an idea, the mentioned adjusting means may comprise a screw member providing accurate and simple adjustment for the sensor.

According to an idea, the sensing device is an in ductive sensor.

According to an embodiment, the sensing device is a distance measuring device.

According to an embodiment, the sensing device may be configured to operate as an on-off switch. Then the sensing device may be arranged to operate as a limit switch. The switch may be an electromechanical switch or contactless sensor. This kind of sensor may be arranged to indicate when the above mentioned angle lever is being turned predeter mined magnitude corresponding to a limit value set for the textile product. It may also be possible to arrange this kind of sensor to measure directly a pivot arm of other moving mechanism of the press roll.

According to an embodiment, the solution relates to a planar washing machine for washing separate planar textile products. The washing machine may comprise: a standing body configured to be mounted on a floor; a feed opening for feeding the textile product into the washing machine; a feed device, which is located at the feed opening and is config ured to feed the textile product in a feed direction towards the washing machine and inside the washing machine during the operation; one or more washing units for washing the textile product inside the washing machine; one or more control units for controlling operation of the machine; and a measuring arrangement comprising one or more sensing de vices or sensors configured to determine thickness of the planar textile product. Further, the feed device comprises a nip through which the textile product is to be fed. The measuring arrangement is configured to determine the thick ness of the textile product by sensing size of the nip.

According to an embodiment, the control unit is configured to detect in response to received sensing data from the measuring arrangement that the textile product fulfills a predetermined minimum thickness value set for the textile products to be washed by the planar washing machine. In other words, the control unit ensures that the textile product to be washed is thick enough to be treated by the machine. Thereby possible problems during the washing process can be avoided. The minimum thickness value may be 3 mm, for example.

According to an embodiment, the control unit may indicate on user interface, such as on a display device, for the user if the planar textile is too thin to be treated in the machine. According to an embodiment, the control unit may be provided with a measuring program to execute the thickness measuring. Before starting a selected washing program, the measuring program is executed. The measuring program may comprises pressing the press roll several times against the textile product and making several measurements. Alterna tively, the pressing may be performed by a predetermined initial pressure which is released and only thereafter the actual thickness sensing is executed. This may be needed when textile products with extremely soft surface, like pile carpets, are being washed.

According to an embodiment, the sensing measures are executed at one lateral edge or side portion of the machine. Then the sensing device is outside a washing space where the actual washing is executed. The sensor and other sensitive components of the arrangement are protected by a side plate against moisture and dirt. Then service life of the sensor may be longer.

According to an embodiment, the body of the machine comprises side plates limiting a washing space inside the machine. The measuring arrangement is supported on an outer surface side of the side plate. An advantage of this solu tion is that maintenance of the adjusting system is facil itated due to easy accessibility. According to an embodiment, the control unit may detect an end or a trailing edge of the textile product being washed in response to the sensing data received form the sensing device.

According to an embodiment, a feed device of the machine comprises at least two rotating support rolls and an endless feed belt arranged to surround them, wherein the textile product is supportable on the feed belt. The feed device further comprises a rotating press roll movable by means of a moving mechanism in vertical direction relative to the feed belt whereby the nip is formed between the feed belt and the press roll. A sensing device is configured to sense movement of the moving mechanism of the press roll.

According to an embodiment, the solution relates to a method of determining thickness of a separate planar tex- tile product in a planar washing machine. The method com prises: feeding the textile product in a feed direction with a feed device during the washing process; determining the thickness of the textile product by means of at least one sensing device; and transmitting sensing data to a control unit of the machine. The method further comprises providing the feed device with a nip whereby the textile product is fed via the nip. The thickness of the textile product is detected at the nip by means of the sensing device config ured to detect position of at least one nip roll. The above disclosed embodiments may be combined in order to form suitable solutions having those of the above features that are needed.

Brief description of the figures

Some embodiments are described in more detail in the accompanying drawings, in which

Figure 1 is a schematic side view of a planar wash ing machine,

Figure 2 is a schematic view of a feed opening of a machine when a textile product is manually positioned, Figure 3 is a schematic view of a the feed opening disclosed in Figure 2 after the manual feed process is completed and a washing process is initiated,

Figure 4 is a schematic side view of a nip and a measuring principle for sensing thickness of a textile prod- uct,

Figure 5 is a schematic side view of a feed device and sensing system for detecting thickness of a textile product, and

Figure 6 is a schematic and highly simplified view of a principle of a separate sensing mechanism actuated by a moving mechanism of a press roll. For the sake of clarity, the figures show some em bodiments of the disclosed solution in a simplified manner. In the figures, like reference numerals identify like ele ments. Detailed description of some embodiments

Figure 1 shows a planar washing machine 1 for wash ing planar textile products 2 such as rugs or similar fur nishing textiles. The washing machine 1 comprises a body 3. The textile product 2 may be fed into the washing machine 1 through a feed opening 4 wherein it is taken over by gripping means 5. The gripping means 5 may comprise one or more holding devices 6 which may include suction ports 7. An underpressure or suction may be led to the suction ports 7 from a suction unit SU or source. The washing machine further comprises feeding means 8, such as rollers, by means of which the textile product 2 may be moved forward in the washing machine 1. In the vicinity of the feed opening 4 there may be a transverse stopper 9 against which a leading end of the textile product 2 is at first fed manually. The stopper 9 may be a mechanical member that may be adapted to be moved in the vertical direction so that it may be moved out of the way of the textile product 2 when the washing cycle is started.

The actual washing may be performed by means of a washing unit WU. The washing unit WU may comprise one or more washing nozzles and two or more suction heads. Washing agent or washing liquid is fed with high pressure from a washing liquid unit LU, and a drying suction may be formed with a suction unit or source SU. The operation of the washing machine 1 may be con trolled by a control unit CU. The control unit CU may au tomatically control the suction of the holding device 6, a hatch 10, feeding or transfer means 8, washing unit WU and generally the entire work cycle of the washing machine 1.

The washing machine 1 washes the rug with the aid of one or more washing agent jets and two or more rotating suction heads. The washing agent used in the washing is water to which washing agent may have been mixed. Further, the washing machine 1 sucks off the water left in the rug after the washing, drying the rug so that when the rug is taken out of the washing machine, no water will run out of it and it will dry fast. The disclosed washing machine 1 may be installed in a launderette where the customers them selves use the washing machine.

Figure 1 further shows that the feed opening 4 is provided with a nip N provided with a movable press roll 12 and a short transfer or feed belt 13 below a feed line. The press roll 12 can be pressed against the upper surface of the textile product 2 and the feed belt 13 is driven for moving the textile product 2 further inside the machine 1. As it is discussed above in this document, thickness of the textile product 2 is detect in connection with the nip N.

Figure 2 discloses that a textile product 2 is fed manually against a stopper 9, which is moved to its lower position. After a leading edge E of the textile product 2 is sensed and its positioning and straightness is accepted by a control unit CU, the holding device 6 is actuated and suction S is directed to suction ports 7. The suction causes vacuum force F which keeps the textile product immovable. Manual grip can be removed and user can take his hands out of the feed opening 4. Thereafter, the stopper 9 moves away, a hatch 10 closes and a press roll 12 is moved against the textile product 2. Position of the press roll 12 can be sensed in order to ensure that thickness of the textile product is suitable. Only thereafter the washing can be started. The press roll 12 may also produce desired nip force NF in the nip N. A feed belt 13 is then activated and the textile product 2 may be transferred in the feed direc tion A. This is disclosed in Figure 3. The feed belt 13 and the nip roll 12 are part of a feed device 15. The feed belt 13 is an endless belt arranged around two support rolls so that they form together a rotating support element 16 below the textile product 2.

Figure 4 discloses a nip N provided with a rotating press roll 12 on a top surfaces side of a textile product 2 and a rotating support element 16 on a bottom surface side. The solution of Figure 4 differs from the solutions shown in the previous Figures 1 - 3 in that the support element 16 of the nip N comprises one single support roll 17 instead of a roll assembly and a feed belt. The press roll 12 is vertically movable. Movement path of the press roll 12 may be linear or curved. The press roll 12 can be moved by means of a moving mechanism 18. The press roll 12 is pressed against the top surface with nip force NF. The support roll 12 can be moved by means of one or more actuators 19, which may be pneumatic cylinders, for example. Position of the press roll 12 in relation to the support element 16 can be detected. A sensing device S or sensor may be arranged to detect 20 movement of the moving mechanism 18, or alternatively, the moving mechanism 18 may be connected to activate a separate mechanical sensing mech anism 21, such as an angle lever, whereby the sensor S is configured to detect 22 movement of the separate mechanism 21. Thus, the moving mechanism 18 may be sensed directly or indirectly. Gathered sensing data may be transmitted to a control unit CU for further processing to detecting thick ness T.

Figure 5 discloses a feed device 15 corresponds to the one shown in Figures 1- 3. The feed device 15 comprises a roll arrangement 23 provided with two support rolls 24, 24 and a feed belt 13 arrange on them. The support rolls

24, 25 and the feed belt 13 form a rotating support element 16 opposite to a press roll 12. The support element 16 is vertically immovable whereas the press roll 12 is movable by means of its moving mechanism 18, which may comprise a turning arm 26. The arm 26 may be turned R1 relative to a pivot point 27 or fulcrum by means of an actuator 19 whereby the press roll 12 can be positioned against the top surface of the textile product 2. When the arm 26 reaches its lower position it may turn R2 a separate sensing mechanism 21 movement of which is detected by means of a sensing device S. The sensing mechanism 21 comprises an angle lever 28 provided with a first lever 29, second lever 30 and a ful crum 31. The pivot arm 26 may contact a roller 32 mounted at a distal end of the first lever 29 when the press roll 12 is moved to its lower position. Then the angle lever 28 turns in relation to the fulcrum 31 and causes the second lever 30 to move relative to the sensor S. Length of the first lever 29 is minor than length of the second lever 30 and this feature allows more accurate sensing.

Figure 6 discloses a sensing arrangement wherein a separate sensing mechanism 21 comprises an angle lever 28, basic structure of which may be the same as is disclosed in Figure 5. The angle lever 28 can be turned around a fulcrum 31 and may be returned by means of spring element 33. The sensor S may be mounted to a fixed support element 34 and its distance from a second lever 30 may be adjusted E by means of adjusting means 35, which may be screw means for example. The angle lever 28 and the support element 34 together with the sensor S may be mounted to a lateral side plate 36 of a planar washing machine. As can be noted, lengths D1 and D2 of the first lever 29 and the second lever 30 are different. When the first lever 29 is moved the second lever 30 executes a greater movement H.

The drawings and the related description are only intended to illustrate the idea of the invention. In its details, the invention may vary within the scope of the claims.