Patent Publication Number: US-10773411-B2

Title: Slicing machine

Description:
CROSS-REFERENCE TO RELATED APPLICATIONS 
     The present application claims priority from DE 102015121142.4 filed Dec. 4, 2015, the disclosure of which is hereby incorporated herein by reference. 
     BACKGROUND 
     The invention relates to a slicing machine according to the features of the present disclosure. 
     Such a slicing machine is known from EP 2 626 178 A1. This slicing machine has a carriage that can be swivelled out and is mounted such that it can pivot on a housing of the slicing machine via a two-part carriage foot. During pivoting from a cleaning position into the slicing position, the carriage is automatically locked by a spring-loaded pin. For swivelling out the carriage, the pin must be released by hand, only then is it possible to swivel the carriage out. This means that an operator needs one hand to release the pin and one hand to pivot the carriage. In the case of correspondingly heavy carriages, it can be problematical to swivel the latter out with only one hand and at the same time to bear the weight of the carriage with this hand. 
     The object of the invention is to create a slicing machine which has a high level of operating safety accompanied by simple and convenient operation. In particular, the slicing machine is to meet high hygiene standards at the same time. 
     This object is achieved according to the invention by a slicing machine and a method for controlling a slicing machine according to the features of the present disclosure. 
     According to the invention it is provided that the locking device has an electrically or electromagnetically operable actuator for releasing the carriage pivot bearing. Through the electrically or electromagnetically operable actuator, the locking device can be automatically released or unlocked in a controlled manner. An additional hand for operating the unlocking system is not necessary. For example, an operator can trigger the unlocking procedure automatically and then swivel the carriage or the supporting plate out with both hands. This makes a convenient and safe operation possible even in the case of slicing machines, the carriages of which have a relatively high weight. 
     The electrical or electromagnetic activation of the actuator to release the carriage pivot bearing can in addition be linked to further conditions or connected to individual actions in order to increase the operating safety of the slicing machine. 
     In an embodiment according to the invention it is therefore provided that, in the cleaning mode, first of all the stop plate is moved in front of the slicing edge of the slicing blade and the drive motor of the slicing blade is stopped, before the locking device is released in an electrically controlled manner. In the case of a carriage swivelled out into the cleaning position, access to the slicing area of the slicing blade is improved. On the one hand this makes simple cleaning possible, but on the other hand it also increases the risk of injury to cleaning staff. By only allowing the locking system to be released after the stop plate has been moved in front of the slicing edge of the slicing blade and the drive motor has been switched off, it is ensured that, during cleaning, the slicing edge of the blade is covered and the slicing blade no longer rotates. The risk of injury to cleaning staff is thereby considerably reduced in comparison with slicing machines with a purely mechanically releasable locking device. In the case of a purely mechanical locking device, for example, if incorrectly operated, the carriage can also be swivelled out while the drive motor of the slicing blade is running. 
     By slicing position is meant a position of the supporting plate in which the supporting plate is arranged orthogonal, i.e. perpendicular, to the slicing blade or the slicing plane. In this slicing position, product to be sliced, for example elongated foodstuffs such as sausages or cheese, is placed on the supporting plate and is fed to the slicing blade for cutting off individual slices by moving the carriage back and forth. 
     By cleaning position is meant a swivelled-out position of the carriage. That is, in the cleaning position, the supporting plate is arranged inclined with respect to the slicing plane and remote from the slicing blade. Thus, in the cleaning position, the surface of the supporting plate can be easily cleaned. In addition, access to the slicing blade is improved with the result that the latter can also be easily cleaned. 
     The slicing machine can, in an embodiment, be configured as a vertical slicer with a circular blade rotating in a vertical slicing plane. 
     In another embodiment, the slicing machine can be configured as an inclined slicer or gravity feed slicer, wherein a circular blade rotates in a slicing plane tilted with respect to the vertical by an angle of approx. 10 to approx. 35 degrees. 
     In particular it is provided that the slicing machine has a stop plate which is arranged in the slicing area and is mounted on the machine housing. The stop plate runs parallel to the slicing blade and can be adjusted transversely in order to set a desired slice thickness. The slice thickness can be set manually via a handle in that the position of the stop plate is adjusted manually via the handle. It can also be provided that the stop plate is adjusted via an electric servomotor. This embodiment has the advantage that no manual operation is required. In addition, the desired slicing thickness can be set precisely via the servomotor. Also in the case of large slicing machines, in which the weight of the stop plate is relatively high, it is advantageous to set the slice thickness via an electric servomotor. 
     In order to increase the ease of use of the slicing machine, it can be provided that the slicing machine comprises different operating modes. A first operating mode can, for example, be a slicing operation. A cleaning mode can be provided as a further operating mode. 
     Switching between the individual operating modes of the slicing machine preferably takes place automatically following the touch of a button, in that, for example, for switching on the cleaning mode, first of all an operation of a switch or of a button of a touchscreen (touch-sensitive screen) is evaluated and, as a result of the operation, the stop plate is moved in front of the slicing edge of the slicing blade in a motorized manner and the drive motor of the slicing blade is stopped, before the locking device is activated to release. It is thus possible for an operator of the slicing machine simply at the touch of a button on the one hand to transfer the slicing machine into a safe state and on the other hand to be able to swivel the carriage out easily. The cleaning mode can, for example, be switched on by operating a switch, for example a press switch or a turn-switch or a push-button. In an embodiment it can also be provided that the slicing machine has a control and/or input device with a touchscreen. For example, an icon can be displayed on the touchscreen as a button which serves for switching on the cleaning mode. By touching this icon, the slicing machine is automatically switched into the cleaning mode. 
     In order to ensure that the slicing blade has actually stopped in the cleaning position, it can be provided in an embodiment that, after the drive motor of the slicing blade has been stopped, a particular time is waited before the locking device is activated to release. 
     In a structural embodiment of the slicing machine it can be provided that the carriage has a two-part carriage foot that connects the supporting plate to the machine housing. The carriage pivot bearing is arranged on the carriage foot, in that the carriage foot has a first carriage foot part and a second carriage foot part mounted pivotably on the latter. The locking device is configured such that it connects the two carriage foot parts to each other releasably. 
     The operating safety is increased, for example, in that it is provided that a safety switching system co-operating with the locking device is present which is connected to a speed sensor for detecting a rotational speed of the slicing blade and/or to a slice thickness sensor for detecting a set slice thickness. The safety switching system is in particular configured such that it only makes it possible or undertakes to activate the actuator to release the carriage pivot bearing when the speed sensor detects that the slicing blade has stopped or has fallen below a limit speed and/or the slice thickness sensor detects a slice thickness setting of less than or equal to zero. The electrically operable actuator can be activated directly via the safety switching system. Alternatively, the safety switching system can also control an operation of the actuator in that, for example, it interrupts or closes a line to the supply voltage of the actuator. As speed sensor for detecting the rotational speed of the slicing blade, a speed sensor co-operating with the drive side of the drive motor of the slicing blade can be used, for example. 
     As speed sensor, an optical sensor, for example a light barrier, or a magnetic sensor, for example a Hall effect sensor can be used, which emits a measurement signal proportional to the rotational speed of the slicing blade. Alternatively, an evaluation of an activation of the drive motor can also take place as speed sensor in that, for example, the current consumption of the drive motor or the voltage induced in the drive motor as a result of the rotation of the slicing blade is evaluated as a measure of a rotational speed of the slicing blade. 
     As slice thickness sensor, for example, a switch can be used which co-operates with the stop plate and detects when the slice thickness of the stop plate is smaller than or equal to zero. Slice thickness smaller than or equal to zero means that the stop plate is arranged completely in front of the slicing edge of the slicing blade with the result that the slicing edge is covered by the stop plate. In the case of a slice thickness setting greater than zero, the slicing edge of the slicing blade is freely accessible, i.e. a slicing operation is then possible. 
     It is also possible for the locking device to be releasable when the slicing blade has not yet stopped, but when the rotational speed of the slicing blade has already fallen below a particular limit value, which makes it possible to clean the slicing blade relatively safely. 
     In an embodiment it can also be provided that the safety switch interrupts the power supply to the servomotor of the stop plate or the safety switching system prevents activation of the servomotor when the safety switch is operated. It is thereby prevented that the stop plate can be adjusted when the carriage is tipped out. It is thus ensured that the position of the stop plate is always covering the slicing edge of the slicing blade (slice thickness smaller than zero) when the carriage is tipped out. 
     In an embodiment it can be provided that, for locking the carriage pivot bearing, the locking device either has a catch that is arranged on a carriage part and is operable by the actuator and, in the slicing position, engages behind a projection arranged on the other carriage part, or has a pin that is arranged on a carriage part and is operable by the actuator and, in the slicing position, engages in a recess arranged on the other carriage part. 
     A high level of operating safety can also be guaranteed in that it can be provided in an embodiment that, on pivoting into the slicing position, the locking device automatically locks the supporting plate, in that the catch or the pin is acted upon by a spring into the locking position, and it is preferably provided that the catch or the pin has a lead-in chamfer or co-operates with a lead-in chamfer. Via the lead-in chamfer, the catch or the pin is first of all pushed back automatically against the force of the spring on bringing the supporting plate or the carriage from the cleaning position into the slicing position. Once the carriage or the supporting plate has reached the slicing position, the catch or the pin, acted upon by the spring, can then be pushed back into the locking position and thus locks the carriage or the supporting plate automatically. To release the locking system, the actuator must then be supplied with current again. For this it can be provided that, for releasing the locking system, the actuator moves the catch or the pin against the force of the spring, preferably that the catch or the pin is connected to a slide plate, wherein the actuator strikes the slide plate in order to operate the catch or the pin. 
     In an embodiment it can be provided that the locking device has a safety switch which, when the locking system is released, interrupts a power supply to the drive motor of the slicing blade. The safety switch prevents the drive motor of the slicing blade from being able to be accidentally set in motion when the carriage is swivelled out or the locking device is released. It is provided that, for the entire duration for which the locking device is released or while the carriage is swivelled out in the cleaning position, the safety switch remains in operation. Only when the locking system locks the carriage in the slicing position again is the safety switch released and then a power supply is again possible to the drive motor of the slicing blade. 
     For this it can, for example, be provided that the actuator has a linearly movable push rod, one end of which is connected to the slide plate and the other end of which operates the safety switch. Via the push rod it is ensured that, as long as the actuator is in the released position, the safety switch remains in operation and the safety switch thus interrupts the power supply to the drive motor of the slicing blade. 
     The position of the actuator in the released position can, on the one hand, be fixed in that the actuator is supplied with current for the entire time. On the other hand, the actuator can also be held mechanically in the released position in order to ensure, even in the case of power failure or when the power supply is switched off, that the safety switch remains in operation during the entire cleaning procedure. For example, it can be provided that the slide plate has a guide mechanism in which a fixed stud is guided in such a way that the stud holds the slide plate in a position that releases the locking system while the supporting plate is being swivelled out. 
     In an embodiment, the actuator can be configured as an electromagnet, preferably as a solenoid, which unlocks the carriage pivot bearing when current is supplied. It is only possible to tip the carriage out into the cleaning position by supplying current. If the power fails, the actuator remains in the locked position and tipping out of the carriage is prevented. 
     In an alternative embodiment it can be provided that the actuator is configured as an electric motor. In particular, the push rod can have a threaded section and the actuator can be configured as a spindle motor which drives a spindle nut co-operating with the threaded section in order to move the push rod linearly. 
     In order to achieve a compact design, it can be provided that the locking device is arranged completely within the carriage foot and/or the supporting plate. The locking device is preferably arranged completely within an installation space, which is enclosed on at least three sides by the carriage foot. 
     In particular it is provided that the carriage foot has a space inside it for receiving the locking device, which space it shields towards the outside. In particular, the space is sealed, preferably protected against water spray. For this, the carriage foot can have, for example, a U-shaped profile which surrounds the installation space on three sides in order to cover the latter. In particular, it can be provided, in the case of a voluminous supporting plate which has a certain thickness, that part of the installation space extends into the supporting plate. This also makes it possible to reduce the necessary overall height since part of the supporting plate is thus also used for the installation space of the locking device. 
     Embodiments can be conceived in which the locking device is controlled purely electrically. Alternatively, it can also be provided, however, that the locking device also has, in addition to the electrically operable actuator, a manually operable, in particular manually releasable, locking element. Via the additional manually releasable locking element there results a further increase in safety and a mechanically stable structure. 
     In an embodiment it can be provided that the carriage can be moved linearly via an electrical carriage drive. The carriage drive can be arranged in the machine housing and co-operates with the first part of the carriage foot. 
     In order to facilitate cleaning of the slicing machine for an operator it can be provided that the carriage can be displaced or moved manually in the cleaning position along the machine housing. 
     It is provided that the slicing machine according to the invention or the control method according to the invention is used for a slicing machine in the food trade and/or in the sale of fresh goods. By means of the slicing machine, foodstuffs, such as for example sausage, cheese or vegetables can be cut into slices and assembled into portions for sale. Alternatively, a use of the slicing machine according to the invention and/or of the control method according to the invention for a slicing machine is also conceivable in the case of food production in that, for example, pre-prepared portions for sale are assembled and then packaged via the slicing machine. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
       Further embodiment examples of the invention are shown in the figures and described below in the associated description. 
       There are shown in, 
         FIG. 1 : a schematic view of the slicing machine according to the invention with a carriage that can be tipped out; 
         FIG. 2 : a representation of the two-part carriage foot in the slicing position with a locked locking device; 
         FIG. 3 : a representation of the two-part carriage foot in the slicing position with a released locking device; 
         FIG. 4 : a representation of the two-part carriage foot in the swivelled-out cleaning position. 
     
    
    
       FIG. 1  shows an embodiment example of a slicing machine  1  according to the invention. The slicing machine  1  has a machine housing  11  with a motor tower. At the top of the motor tower, a control and display device  15  for operating the slicing machine  1  is arranged. A drive motor, not shown, for a slicing blade  2  is received in the motor tower. 
     The slicing blade  2  is arranged in a vertically orientated slicing plane and configured as a circular blade. The slicing blade  2  is covered, in the area of its slicing edge, by an essentially C-shaped blade guard ring  22 , in order to prevent unintentional contact with the slicing edge of the slicing blade  2 . The flat front side of the slicing blade  2  is covered with a blade cover  23  in order to prevent accidental contact with the flat side of the rotating slicing blade  2  during the slicing operation. 
     The slicing area of the rotating slicing blade  2  is defined by an area left free by the blade guard ring  22 . In front of this slicing area, a stop plate  12  running parallel to the slicing blade  2  and transversely displaceable is mounted on the machine housing  11 . Via a handle  13 , a desired slice thickness can be set by moving the stop plate  12  transversely with respect to the slicing plane. In an alternative embodiment, which is not shown in the figures, the handle can also be omitted and the stop plate is adjusted purely in a motorized manner via an electric servomotor. 
     A carriage  3  which can be displaced linearly parallel to the slicing plane is arranged in an area in front of the slicing blade  2 . The carriage  3  has a carriage foot  34  and a supporting plate  31  for supporting product to be sliced. The supporting plate  31  is connected on its underside to the carriage foot  34 . The carriage  3  is mounted displaceably on a linear guide  17  of the machine housing  11  via the carriage foot  34 . 
     The carriage  3  comprises a hand guard  32  as well as a holder for product to be sliced  33 . Both the holder for product to be sliced  33  and the hand guard  32  are formed partially transparent in order to provide an operator with a view onto the carriage  3  or onto the slicing area. Product to be sliced is placed on the surface of the supporting plate  31  and held by the holding device for product to be sliced  33 . During the slicing procedure, the product to be sliced is conveyed to the slicing blade  2  by means of the holding device for product to be sliced. By moving the carriage  3  back and forth, individual slices are cut from the product to be sliced using the slicing blade  2 . 
     The slices cut off by the slicing blade  2  are received behind the slicing blade  2  by a chain frame  14  and conveyed transversely to the slicing plane. Via a pivotable flick ejector  14   a , the slices are removed from the chain frame  14  and deposited in a depositing area  16 . 
     The carriage foot  34  is configured in two parts and has a pivot bearing  35  with a pivot axle  36  in order to pivot the carriage  3  or the supporting plate  31  from the slicing position shown in  FIG. 1  into a cleaning position. In the slicing position shown in  FIG. 1 , the carriage is locked via a locking device  4 . This means that the carriage  3  cannot be brought from the slicing position into the cleaning position without releasing the locking device  4 . 
     In  FIGS. 2 to 4 , a detailed representation of the two-part carriage foot  34  is shown. The carriage foot  34  has a first carriage foot part  341  and a second carriage foot part  342  mounted pivotably on the latter. The carriage foot part  341  is mounted on the machine housing  11  via a linear guide  17  such that it is linearly displaceable. The linear guide  17  has a sliding axle  171  which forms a slide bearing for the first carriage foot part  341 . A torque support  172  is arranged above the sliding axle  171  in order to support a torque arising through the weight of the carriage  3  or of the product to be sliced. 
     Between the first carriage foot part  341  and the second carriage foot part  342 , the pivot bearing  35  is arranged with a pivot axle  36  arranged parallel to the sliding axle  171 . The second carriage foot part  342  is connected to the first carriage foot part  341  via the pivot axle  36 . The second carriage foot part  342  is configured as a U-shaped profile which engages around the first carriage foot part  341  and has, inside it, an installation space  38  for receiving components. 
     Components of the locking device  4  are arranged in the installation space  38 . The locking device  4  has a slide plate  43  which is connected in one piece to a catch  421  and is mounted displaceably on the second carriage foot part  342 . At the lower part of the slide plate  43 , a guide mechanism  431  is provided which co-operates with a stud  37  arranged fixed on the first carriage foot part  341 . On the top of the slide plate  43 , this guide mechanism is connected to a push rod  411  of an electric solenoid  41 . When current is supplied, the slide plate  43  is displaced upwards by the electric solenoid into the unlocking position shown in  FIG. 3 . When no current is supplied, the slide plate  43  is acted upon downwards by the force of a spring  412 , i.e. into the locked position. It is thereby ensured that, when no current is supplied, the slide plate  43  is always pushed into the locked position. 
     The installation space  38  is sealed against water spray. The push rod  411  also has an O-ring as seal with the result that water spray protection according to IPX5 is achieved. 
     The locked position is shown in  FIG. 2 . In the locked position, the catch  421  engages behind a projection  422  arranged on the first carriage part  341 . The second carriage part  342  is thereby locked or fixed on the first carriage part  341 . In addition, as shown in  FIG. 2 , an additional mechanical locking system is provided, consisting of a bolt  44  and a handle  45  connected to the latter. For locking, the bolt  44  is screwed to the first carriage part  341  via the handle  45  with the result that the bolt produces a further mechanical connection between the second carriage part  342  and the first carriage part  341  supplementary to the catch  421 . 
     To release the locking device  4 , first of all the mechanical locking system is released by unscrewing the handle  45 . Then, as shown in  FIG. 3 , the actuator  41  is supplied with current and operates the slide plate  43 . That is, it pulls the slide plate  43  into the unlocking position shown in  FIG. 3 . The solenoid  41  is therefore working against the force of the spring  412 . Alternatively, the actuator  41  can also be supplied with current first of all to release the locking device  4  and then the mechanical locking system can be released. 
     The electric solenoid  41  has an actuating cam  413 , which co-operates with a safety switch  46 , on the end of its push rod  412 . The safety switch  46  serves to interrupt the power supply to the drive motor of the slicing blade  2  and/or of an electric servomotor for adjusting the stop plate  12 . In the unlocking position shown in  FIG. 3 , the safety switch  46  is operated by the actuating cam  413 . By operating the safety switch  46 , the power supply to the drive motor of the slicing blade  2  and/or to the servomotor is interrupted, with the result that the slicing blade  2  can no longer be started and the position of the stop plate  12  can no longer be adjusted when the locking device  4  is released. As long as the safety switch  46  remains in operation, it is not possible to switch on the drive motor of the slicing blade  2 . 
     To bring the carriage  3  into the cleaning position, the latter must be tilted or swivelled out. That is, starting from the slicing position shown in  FIG. 3 , when the locking device is released, the carriage  3  is tilted outwards with the result that the latter passes into the cleaning position shown in  FIG. 4 . When the carriage  3  is tipped out, the second carriage foot part  342  is pivoted relative to the first carriage foot part  341 . The stud  37  therefore enters a holding section of the guide mechanism  431 . The slide plate  43  is thereby prevented from being able to be pushed back out of its upper position shown in  FIG. 3 . The slide plate is therefore held in the unlocked position via the stud  37 . The holding section of the guide mechanism  431  extends over an area which covers almost the entire pivot movement. The slide plate  43  is thus held in its upper position during the entire swivelling out procedure. At the same time it is ensured that the safety switch  46  remains in operation via the actuating cam  413  during the entire pivoting procedure. 
     Only when the guide stud  37  comes out of engagement with the holding section of the guide mechanism  431  shortly before reaching the slicing position, when the carriage  3  is pivoted back, can the slide plate  43  be moved downwards, acted upon by the spring  412 , i.e. into the locking position shown in  FIG. 2 . 
     In order to prevent catching when pivoting the carriage  3 , it is provided that the catch  421  has a lead-in chamfer  423 . As long as the lead-in chamfer  423  comes into contact with the first carriage foot part  341  or the projection  422  when the carriage is pivoted back into its slicing position, the slide plate  43  is pushed upwards as a result of the lead-in chamfer  423 , with the result that the catch  421  can pass without interfering with the projection  422 . Only once the catch  421  has completely passed the projection  422  is the catch pushed into the locking position, acted upon by the spring  412 . In the locking position, the catch  421  engages with its locking section behind the projection  422  on the first carriage foot part  341 . 
     Thereby, on the one hand, a problem-free and catch-free pivoting of the carriage  3  is ensured and, on the other hand, it is ensured that, on pivoting the carriage  3  into the slicing position, the latter is automatically locked. Even if an operator of the slicing machine forgets to fix the additional mechanical safeguard again by turning the handle  45 , the carriage  3  is nevertheless locked securely in the slicing position via the catch  421  and secured against unintentional swivelling out. 
     LIST OF REFERENCE NUMBERS 
     
         
           1  Slicing machine 
           11  Machine housing 
           12  Stop plate 
           13  Slice thickness setting 
           14  Chain frame 
           14   a  Flick ejector 
           15  Control and display device 
           16  Depositing area 
           17  Linear guide 
           171  Sliding axle 
           172  Torque support 
           2  Slicing blade 
           21  Blade cover 
           22  Blade guard ring 
           23  Blade cover 
           3  Carriage 
           31  Supporting plate 
           32  Hand guard 
           33  Holder for product to be sliced 
           34  Carriage foot 
           341  First carriage foot first part 
           342  Second carriage foot part 
           35  Carriage pivot bearing 
           36  Pivot axle 
           37  Stud 
           38  Installation space 
           4  Locking device 
           41  Actuator 
           411  Push rod 
           412  Spring 
           413  Actuating cam 
           421  Catch 
           422  Projection 
           423  Lead-in chamfer 
           43  Slide plate 
           431  Guide mechanism 
           44  Locking element 
           45  Handle 
           46  Safety switch