Patent Publication Number: US-2004056140-A1

Title: Transport installation for paper reels, method for its operation and vehicle

Description:
FIELD OF THE INVENTION  
       [0001] The invention relates to a transport installation for feeding paper reels to at least one reel stand, as used in particular in printing works, a method for operating the same and a vehicle for use in such a transport installation.  
       PRIOR ART  
       [0002] Installations and methods of the generic type have long been known, cf. for example U.S. Pat. No. 5,076,751. There, for example, transport installations as described in EP-A-0 587 015 are used on the loading track and the track section, in which transport installations the carriage carrying the reel frictionally engages with a transport chain which revolves along the track. For further installations having rail-guided driven carriages for the reel transport, reference is made to DE-A-198 60 475, GB-A-2 181 117 and U.S. Pat. No. 6,155,516. Other transport installations for feeding paper reels to reel stands are known as automatic guided vehicle (AGV) systems. They comprise driven controllable carriages (cf. for example EP-A-0 334 366) which follow wires laid in the floor and, for example, are supplied with energy by a battery and are radio controlled.  
       [0003] Installations of the first-mentioned type can be completely or partly equipped with transport chains, the carriages being moved manually over installation parts not provided with such chains. The equipment with transport chains is relatively complicated. Sliding platforms, optionally also turntables, must be provided with separate transport chains and corresponding drives, so that it is precisely the automatic loading of the reel stands, which is particularly desirable since the environment of the reel stands constitutes a danger area, which requires a relatively high degree of complexity. In installations of the second-mentioned type, the costs for the drives and controls play a considerable role, especially if a relatively large number of carriages is used.  
       [0004] A vehicle according to the precharacterizing clause of claim 9 is disclosed in DE-A-23 34 141. It serves for moving carriages carrying material to be distilled in a distillery on a rail system laid above the floor. However, it is scarcely suitable for use in an installation according to the invention. Since the paper reel has considerable weight but, because it does not rest on the driven vehicle, does not contribute to the pressure of the driven wheels, sufficient traction is not necessarily ensured.  
       SUMMARY OF THE INVENTION  
       [0005] It is the object of the invention to provide a transport installation of the generic type in which complexity and costs both for the tracks and for the carriages are relatively low. This object is achieved by the features in the characterizing clause of claim 1.  
       [0006] In the installation according to the invention, complicated transport means in the tracks are not required. At the same time, the number of relatively expensive drives and controls can be kept low. In general, it corresponds to the number of reel stands, while the number of carriages can be substantially higher, so that it is possible, for example, to process a relatively large number of reels and to store them temporarily on carriages. The embodiment according to the invention is particularly advantageous in the case of transport installations in which only the reel stands are automatically loaded while the reel transport is performed by means of manually driven carriages. In addition, a suitable method for operating the transport installation according to the invention is provided.  
       [0007] Furthermore, a vehicle particularly suitable for use in a transport installation according to the invention is to be provided. This object is achieved by the features in the characterizing clause of claim 9. In the vehicle according to the invention, the drivable wheels are pressed against the rails independently of its weight, whereby sufficient frictional engagement is assured. 
     
    
    
     BRIEF DESCRIPTION OF THE DRAWINGS  
     [0008] The invention is explained in more detail below with reference to figures which represent only an embodiment.  
     [0009]FIG. 1 shows a plan view of a transport installation according to the invention,  
     [0010]FIG. 2 shows a side view of a vehicle according to the invention,  
     [0011]FIG. 3 shows a longitudinal section through an end segment of a vehicle and an abutting end segment of a carriage coupled thereto,  
     [0012]FIG. 4 shows a front view of the vehicle according to  
     [0013]FIG. 2 and a section through a track on which said vehicle can travel and  
     [0014]FIGS. 5 a - o  show the feeding of a new paper reel to a reel stand by means of the transport installation according to the invention, including the removal of a reel core or residual reel which is exchanged for it. There,  
     [0015]FIG. 5 a  shows a part of the transport installation according to the invention from FIG. 1 at the beginning of reel feed,  
     [0016]FIG. 5 b  shows the installation part from FIG. 5 a  after a first step of the reel feed,  
     [0017]FIG. 5 c  shows the installation part of FIG. 5 a  after a second step of the reel feed,  
     [0018]FIG. 5 d  shows the installation part of FIG. 5 a  after a third step of the reel feed,  
     [0019]FIG. 5 e  shows the installation part of FIG. 5 a  after a fourth step of the reel feed,  
     [0020]FIG. 5 f  shows the installation part of FIG. 5 a  after a fifth step of the reel feed,  
     [0021]FIG. 5 g  shows the installation part of FIG. 5 a  after a sixth step of the reel feed,  
     [0022]FIG. 5 h  shows the installation part of FIG. 5 a  after a seventh step of the reel feed,  
     [0023]FIG. 5 i  shows the installation part of FIG. 5 a  after an eighth step of the reel feed,  
     [0024]FIG. 5 j  shows the installation part of FIG. 5 a  after a ninth step of the reel feed,  
     [0025]FIG. 5 k  shows the installation part of FIG. 5 a  after a tenth step of the reel feed,  
     [0026]FIG. 5 l  shows the installation part of FIG. 5 a  after an eleventh step of the reel feed,  
     [0027]FIG. 5 m  shows the installation part of FIG. 5 a  after a twelfth step of the reel feed,  
     [0028]FIG. 5 n  shows the installation part of FIG. 5 a  after a thirteenth step of the reel feed and  
     [0029]FIG. 5 o  shows the installation part of FIG. 5 a  at the end of the reel feed. 
    
    
     DESCRIPTION OF THE PREFERRED EMBODIMENTS  
     [0030] The transport installation according to the invention comprises (FIG. 1) a paper reel store, in particular a buffer store  1 , for holding unpacked paper reels provided with adhesive patches, i.e. prepared for reel change, from which store a straight feed track  2  leads via a plurality of turntables  3 , at each of which a loading track  4 , which leads to a sliding platform  5  or a lifting platform of a reel stand  6 , branches off at right angles. When the sliding platform  5  is in a transfer position, the loading track  4  is flush, on the feed side of the sliding platform  5 , with a track section  7  thereon. On the side facing away from the feed side, there is an adjacent storage track  8  which is flush with the loading track  5 .  
     [0031] A nondriven carriage  9   a  which can receive a paper reel  10  is capable of travelling on each of the loading tracks  4 , and a reel core basket  11  for receiving reel cores of spent paper reels is arranged on a further nondriven carriage  9   b  which is usually parked on the storage track  8 . Between the two carriages  9   a ,  9   b , a vehicle  12  is capable of travelling on the loading track  4 , the track section  7  and the storage track  8 , which vehicle can be coupled both to the carriage  9   a  serving for paper reel transport and to the carriage  9   b  carrying the reel core basket  11 .  
     [0032] The vehicle  12  has (FIGS.  2 - 4 ) a frame  13 , on the underside of which a pair of wheels  14 ;  15  is mounted in the vicinity of each of the two ends. The axle carrying the pair  14  of wheels is driven by an electric motor  16  via a step-down gear  17  and a mitre gear  18  which is suspended from the underside of the frame  13 . The electric motor  16  is supplied with power via current collectors  19  and a power unit  20  having a converter, and is controlled by a control unit  21 . A marker  22  serves for determining the position of the vehicle  12 , as will be explained in more detail further below. Mounted approximately in the middle of the vehicle  12 , in the frame, is a pair of pressure wheels  23  which, in an unloaded starting position, project slightly beyond the wheels  14 ,  15  but can be pressed down against an elastic restoring force. Buffer-like switchable electromagnetic coupling elements  24  for coupling to carriages are mounted at both ends of the frame  13 . Sensors which are in the form of switches  25  and which determine whether a carriage  9  is coupled to the vehicle  12  or not are mounted below the coupling elements  24 . The electromagnetic coupling elements  24  each have (FIG. 3) a winding  26  which surrounds a projecting core  27  having a flat contact surface at the end. Said contact surface can rest against an end face on the housing of the coupled carriage  9 . The switch  25  comprises a pin  28  which is held by the coupled carriage  9 , against the force of a pressure spring  29 , in a retracted position.  
     [0033] The carriage  9  is formed in a manner known per se with a chassis  30  capable of travelling underfloor on the track and a trough  31  which is arranged above the floor and intended for receiving a paper reel or a reel core basket, etc. and which is connected to the chassis  30  by means of a web. They can in this respect correspond to the carriages described in EP-A-0 587 015. The chassis  30  has, at both ends, end faces which are normal to the longitudinal direction and are formed by an end wall  32  consisting of ferromagnetic material and which the coupling elements  24  of the vehicle  12  can engage.  
     [0034] The track is laid underfloor and comprises (FIG. 4), in a manner known per se, two rails  33  in the form of U-profiles which face one another and are supported by means of supporting profiles and thresholds on the bottom of a trench. It is cast in concrete and covered by cover plates  34  which rest on the rails  33  and leave free only a narrow gap  35  located in the middle above the rails  33 . The insides of the lower flanges of the rails  33  form running surfaces on which the wheels  14 ,  15  run, while the pressure wheels  23  press elastically against the insides of the upper flanges so that the driven wheels  14  are pressed against the running surfaces and have a reliable frictional connection with the rails  33 . The diameters of the wheels  14 ,  15  and of the pressure wheels  23  are preferably identical and only slightly smaller than the distance between the flanges of the rails  33 . Two conductor rails  36  with which the current collectors  19  are in contact are laid in the middle between the running surfaces. A cable duct  37  runs along one of the rails  33 , on the outside thereof and parallel thereto. The vehicle  12  is present substantially between the rails  33  and does not project above the cover plates  34  so that collision with objects lying on the floor or with persons need not be feared.  
     [0035] The vehicles  12  can be controlled substantially by a stationary control unit, while the control unit  21  performs in each case only elementary functions. The position of the vehicle is monitored by virtue of the fact that the marker  22  is detected by active sensors on the track. In many cases, it is sufficient if in each case only the presence of the vehicle  12  at specific stopping points and other switching points is detected. On the other hand, the position of the vehicle can also be constantly updated by the control unit, for example by calculating the travel distance by monitoring the wheel revolutions, the detection merely resulting in recalibration of the position. In this case, a single sensor which is regularly passed and then triggers a recalibration in each case may also be sufficient.  
     [0036] Instead of the marker  22 , it is also possible to provide an active sensor, whereas only markers which are detected by the sensor are mounted on the track. The markers can be uniquely identified or indistinguishable and mounted only at specific points or at regular intervals. The detection can be communicated by the vehicle to the control unit via the conductor rails, by radio or by modulated infrared beam. Also conceivable is position monitoring by a measuring beam in the track, which interacts with a reflector on the vehicle, but in this case the cross-section of the vehicle as well as of the carriage must not hinder the measuring beam between transmitter and reflector, and moreover position monitoring requires additional installations on the track section  7  of the sliding platform  5 .  
     [0037] The vehicle  12  may be in certain travel states, such as ‘stop’, ‘slow forwards’, ‘fast forwards’, ‘slow reverse’, ‘fast reverse’, where ‘fast’ can correspond, for example, to 0.2 m/sec and ‘slow’ to about a fifth thereof. It can be switched in each case by a specific switching command from the control unit to a specific travel state, in which it remains until it receives a further switching command. Alternatively, it can remain in a state for as long as it periodically receives a corresponding command and return to a ground state, such as ‘stop’ when the commands cease.  
     [0038] Normally, the vehicle  12  can be driven ‘fast’ but, on passing a sensor upstream of the stopping point to be approached, can be switched to ‘slow’ so that, as soon as the marker  22  is detected by a further sensor at the stopping point and switching to ‘stop’ is triggered, it can stop virtually instantaneously. The commands can be transmitted by the control unit once again via the conductor rails  36 , by radio or by a modulated infrared beam to the vehicle  12 . If the vehicle carries an active sensor, certain transitions, such as, for example, ‘slow forwards’-‘stop’ or ‘fast forwards’-‘slow forwards’, can also be triggered directly by signals thereof if it responds to a stopping point or to a switching point upstream thereof.  
     [0039] Instead of being supplied with energy via conductor rails, the vehicle can also be supplied with energy in any other manner. It may carry, for example, an energy store, for example a battery, so that no permanent energy transmission is required.  
     [0040] A reel change on one of the loading tracks  4  is described below with reference to FIGS. 5 a - o.    
     [0041]FIG. 5 a  shows the starting position after a reel change and before changing of the reel core or residual reel for a new paper reel. The two-arm reel stand  6  carries an empty reel core or a virtually empty reel core, i.e. a virtually completely spent, separated residual reel and a paper reel which has just been unwound (not shown). On the feed side of the sliding platform  5 , the carriage  9   a  with the new, unpacked paper reel  10  provided with an adhesive patch is parked in the vicinity of the turntable  3 , on a waiting station of the loading track  4 , and the vehicle  12  is parked at a stopping point adjacent to the sliding platform  5 , which is present in the transfer position. The carriage  9   b  with the reel core basket  11  is on the storage track  8 .  
     [0042] In order to remove the reel core from the reel stand, the vehicle  12  first travels ‘fast forwards’ over the rail section  7  of the sliding platform  5  onto the storage track  8  to a switching point where it is switched to ‘slow forwards’. At low speed, it travels with switched-on coupling elements to the carriage  9   b , which carries the reel core basket  11  and is switched to ‘stop’ as soon as the sensor of the front coupling element responds (FIG. 5 b ). The vehicle  12  then travels in ‘fast reverse’ back to the track section  7 , where, on passing a switching point, it is switched to ‘slow reverse’ and thus approaches a stopping point at which it is switched to ‘stop’ and halts.  
     [0043] The carriage  9   b  with centred reel core basket  11  stands on the sliding platform (FIG. 5 c ). Since the track section  7  is too short also to hold the vehicle  12  completely, the coupling elements are switched off and the vehicle  12  is moved in ‘fast reverse’ a short distance to a stopping point on the loading track  4 , so that it is free of the track section  7  (FIG. 5 d ). The sliding platform  5  is now pushed against the reel stand  6  until the reel core basket  11  stands under the reel core, which is now released by the cones of the reel stand  6  and falls into the reel core basket  11  (reel core  38 , FIG. 5 e ). The sliding platform  5  is moved back to the transfer position (FIG. 5 f ) and then the carriage  9   b  is pushed by the vehicle  12  back onto the storage track  8  (FIG. 5 g ).  
     [0044] For feeding the paper reel  10 , the vehicle  12  now travels once again in ‘fast reverse’ to a switching point shortly before the stopping position and then continues travelling with switched-on coupling elements in ‘slow reverse’ until it comes into contact with the carriage  9   a , couples to said carriage and is switched to ‘stop’ (FIG. 5 h ). Switched to ‘fast forwards’, the vehicle  12  now travels with the carriage  9   a  over the loading track  4  back to the sliding platform  5 , where it once again passes a switching point and, switched to ‘slow forwards’, approaches a stopping point, at which the paper reel  10  is centred on the sliding platform  5  (FIG. 5 i ). If the paper reel  10  does not always rest exactly centred on the carriage  9   a  or if different reel widths are possible, the passage of its front edge or of the front edge and of the rear edge can be detected by a light barrier, and an adjusting displacement can be performed after reaching the stopping point.  
     [0045] The vehicle  12  is then uncoupled and is moved to a stopping point on the storage track  8 , on which it is free from the track section  7  (FIG. 5 j ). Thereafter, the sliding platform with the carriage  9   a  is moved towards the reel stand  6  and the paper reel  10  is clamped between the cones which have become free through the ejection of the reel core (FIG. 5 k ) and said paper reel is raised from the carriage  9   a . The sliding platform  5  with the carriage  9   a  is then moved back to the transfer position (FIG. 5 l ). The vehicle now travels with switched-on coupling elements  24  in ‘slow reverse’ onto the track section  7  of the sliding platform  5  until it comes into contact with the carriage  9   a  and couples to it (FIG. 5 m ). Thereafter, the vehicle  12  travels in ‘fast reverse’ over the track section  7  and the loading track  4  up to the switching point upstream of the waiting station and in ‘slow reverse’ until it reaches a stopping point, where at the same time the carriage  9   a  occupies the waiting station (FIG. 5 n ). The coupling elements are then switched off and the vehicle  12  is moved back to its stopping point adjacent to the sliding platform  5  (FIG. 5 o ). Thus, the starting stage is once again reached, with the difference that the carriage  9   a  carries no paper reel.  
     [0046] The carriage  9   a  can then be moved manually and replaced by a carriage which is loaded with a paper reel and which is likewise moved manually to the waiting station. If the transport installation is appropriately equipped, the carriage  9   a  can, however, also be loaded with a new paper reel at the waiting station, which paper reel is brought directly from the buffer store, for example by means of a crane system.  
     [0047] Of course, many modifications and extensions of the installation described are possible. Thus, for example, if the reel cores are to be disposed of via the transport installation as soon as the reel core basket is full, a further storage track can be provided parallel to the storage track in the displacement region of the sliding platform, on which further storage track the vehicle is temporarily parked so that it is out of the way and the carriage with the reel core basket can be moved manually over the track section and the loading track to a disposal station.  
     [0048] Instead of being fed via the feed track and the turntables, the loading tracks can also be fed by a movable carriage which is in the form of a sliding platform and can be moved parallel to the row of reel stands and carries a track section which is oriented transversely, i.e. parallel to the loading tracks, and at whose end a coupling element and a sensor which correspond to those of the vehicle are provided for holding a carriage at a loading position. The carriage standing in the loading position on the movable carriage is in this case loaded at the buffer store by means of a crane or by telescopic arms and then the movable carriage is moved until its track section is flush with a selected loading track, whereupon the vehicle travels on the track section, couples to the carriage and pulls it over the loading track onto the sliding platform. The reel feed from the buffer store takes place automatically in this case.  
     [0049] List of Reference Symbols  
     [0050] 1  Buffer store  
     [0051] 2  Feed track  
     [0052] 3  Turntable  
     [0053] 4  Loading track  
     [0054] 5  Sliding platform  
     [0055] 6  Reel stand  
     [0056] 7  Track section  
     [0057] 8  Storage track  
     [0058] 9 ,  9   a,b  Carriage  
     [0059] 10  Paper reel  
     [0060] 11  Reel core basket  
     [0061] 12  Vehicle  
     [0062] 13  Frame  
     [0063] 14 ,  5  Wheels  
     [0064] 16  Electric motor  
     [0065] 17  Step-down gear  
     [0066] 18  Mitre gear  
     [0067] 19  Current collector  
     [0068] 20  Power unit  
     [0069] 21  Control unit  
     [0070] 22  Marker  
     [0071] 23  Pressure wheels  
     [0072] 24  Coupling elements  
     [0073] 25  Switch  
     [0074] 26  Winding  
     [0075] 27  Core  
     [0076] 28  Pin  
     [0077] 29  Pressure spring  
     [0078] 30  Chassis  
     [0079] 31  Trough  
     [0080] 32  End wall  
     [0081] 33  Rails  
     [0082] 34  Cover plates  
     [0083] 35  Gap  
     [0084] 36  Conductor rails  
     [0085] 37  Cable duct  
     [0086] 38  Reel core