Patent Publication Number: US-2012031926-A1

Title: Delivery Device for Fluid Products and Relative Delivery Method

Description:
FIELD OF THE INVENTION 
     The present invention concerns a delivery device for fluid products, semi-fluids, pastes, gels or creams, such as for example coloring products, food products or other, and the relative delivery method. 
     In particular, the delivery device according to the present invention is suitable for the selective delivery of fluid products such as colorants of different shades or color, creams of different flavor or other, able to be dosed and/or added to a base substance so as to form a paint or varnish or other fluid product, of a determinate color or flavor. 
     BACKGROUND OF THE INVENTION 
     Devices are known for dispensing fluid products, semi-fluids, pastes, gels or creams, such as for example coloring products, food products or other. Known dispenser devices comprise a plurality of containers or canisters, each suitable to contain a predetermined fluid, colorant or food product, and connected to an associated delivery unit, such as for example a piston pump or bellows pump. 
     The canisters and the associated delivery units are mounted on a rotating table suitable to rotate so as to position the delivery units, according to a predetermined sequence, in correspondence with a delivery position. In the delivery position, a specific delivery unit is able to dispense, in the desired quantity, the fluid of the corresponding container toward an outlet container, allowing to fill it with one or more of said fluids so as to obtain a fluid with a desired composition and/or formula. 
     Each delivery unit is provided with a nozzle with which a valve is associated, normally of the ball type, provided with a through pipe. The ball valve is mobile between a closed position, in which it is disposed with the through pipe substantially transverse inside the nozzle, to prevent the fluid leaking from the nozzle. The ball valve is also mobile to at least an open position, in which it is rotated so as to align its through pipe with the nozzle, therefore allowing the fluid to pass and be delivered. 
     One disadvantage of the known delivery device is that, despite the fact that at least part of the fluid present in the pipe of the ball valve is in contact with the fluid present in the nozzle, part of said fluid can dry out, which causes an obstruction of the pipe of the ball valve, especially in the event of a prolonged non-use of the corresponding delivery unit. This entails the need for frequent maintenance interventions, with consequent and extended downtimes of the machine. 
     One purpose of the present invention is to achieve a delivery unit for fluid products that allows a selective delivery, in the desired quantities, of one or more fluid products, minimizing the maintenance times and interventions. 
     Another purpose is to perfect a dispensing method which allows to selectively deliver, with the maximum dosing accuracy, one or more fluid products in the desired quantities, even minimal. 
     The Applicant has devised, tested and embodied the present invention to overcome the shortcomings of the state of the art and to obtain, these and other purposes and advantages. 
     SUMMARY OF THE INVENTION 
     The present invention is set forth and characterized in the independent claims, while the dependent claims describe other characteristics of the invention or variants to the main inventive idea. 
     In accordance with the above purposes, a delivery device for fluid products according to the present invention is suitable to dispense or deliver fluid products, semi-fluids, pastes, gels or creams such as for example coloring products, food products or other. 
     The delivery device comprises a plurality of containers or canisters, each suitable to contain a predetermined fluid, colorant or food product, and connected to an associated delivery unit and comprising a corresponding piston unit or piston pump. 
     The delivery device also comprises a rotary support on which said plurality of containers is mounted. The support rotates so as to position sequentially, at different moments of time and according to one or more predetermined sequences, at least part of the delivery units in a corresponding delivery position, so as to deliver predetermined quantities of fluid into an outlet container so as to obtain a final product with a desired final composition and/or formula. 
     According to a characteristic feature of the present invention, each delivery unit is provided with at least a delivery valve of the disk type, able to be activated between at least two different open conditions and a closed condition. 
     According to a variant, the device also comprises first actuation means and second actuation means able to cooperate with each of said delivery units when the selected delivery unit is disposed, by selective rotation of the rotary support, in the delivery position, in order to drive respectively the corresponding piston unit and the associated delivery valve between the specific open condition and the closed condition. 
     According to a variant of the present invention, the disk type delivery valve is made of ceramic material. 
     According to a variant of the present invention, the first actuation means are able to assume an inactive position in which they do not interfere mechanically with the delivery valve during the rotation of the support. 
     A variant of the present invention provides that said rotary support is moved in opposite directions of rotation so as to position in succession, according to the pre-established delivery sequences, said delivery units in the delivery position so as to minimize the overall travel of the support during the delivery sequence. 
     According to another variant of the present invention, the device comprises stirrer means, associated with the containers and able to mix the fluids contained in the containers. At least some of the stirrer means in each container are able to be selectively activated, independently of each other, so as to keep the corresponding fluid contained in optimum conditions to allow an efficient delivery thereof. 
     According to another variant the stirrer means are able to be selectively activated independently of the movement of the rotary support and/or its direction of rotation. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
       These and other characteristics of the present invention will become apparent from the following description of a preferential form of embodiment, given as a non-restrictive example with reference to the attached drawings wherein: 
         FIG. 1  is a perspective view of a delivery device according to the present invention; 
         FIG. 1A  is a schematic view from above of a detail of the delivery device in  FIG. 1 ; 
         FIG. 1B  is a block diagram of the delivery device in  FIG. 1 ; 
         FIG. 1C  is a schematic view from above of the delivery device in  FIG. 1 ; 
         FIG. 2  is a three-dimensional view of a delivery unit of the device in  FIG. 1 ; 
         FIG. 3  is a front view of the delivery unit in  FIG. 2 ; 
         FIG. 4  is a section view from IV to IV of  FIG. 3 ; 
         FIG. 5  is a lateral view of the delivery unit in  FIG. 2 ; 
         FIG. 5A  is a view from above of the delivery unit in  FIG. 2 ; 
         FIG. 5B  is a view from below of the delivery device in  FIG. 2 ; 
         FIG. 6  is a three-dimensional view of a first actuation unit of the device in  FIG. 1 ; 
         FIGS. 6A-6C  are views respectively from below, the side and the front of the actuation unit in  FIG. 6 ; 
         FIGS. 7A-7B  are perspective views of a second actuation unit of the device in  FIG. 1 ; 
         FIGS. 8A-8D  are lateral views of some delivery steps of the device in  FIG. 1 ; 
         FIG. 9  is a partly sectioned lateral view of a first detail of the device in  FIG. 1 ; 
         FIG. 10  is a partly sectioned lateral view of a container of the delivery device in  FIG. 1 ; 
         FIG. 10A  is a three-dimensional view of the container in  FIG. 4 . 
     
    
    
     DETAILED DESCRIPTION OF A PREFERENTIAL FORM OF EMBODIMENT 
     With reference to the attached drawings, a delivery device  10  according to the present invention comprises a support frame  12 , a rotary table  13 , a plurality of containers or canisters  16 , associated with an equal number of dosing circuits or delivery units  21 , provided with pistons  21   a,  a delivery valve  30  and an actuation unit  40 , able to cooperate with each dosing circuit  21 . The device  10  also comprises a control board  50 , comprising a control and processing unit  51 . The delivery device  10  is also advantageously provided with a box-like containing casing, not shown in the drawings. 
     The rotary table  13 , substantially of a circular shape ( FIGS. 1 and 1A ), is attached in a known manner to a horizontal shelf  14  of the frame  12  and is movable in two opposite directions of rotation, as indicated by the arrow F, around an axis of rotation X orthogonal to the table  13 . The canisters  16  containing the colorants are disposed on the upper surface of the table  13 , according to a predetermined disposition. In this case there are twenty four dosing circuits  21 , and twenty four canisters  16 . The dosing circuits  21 , each of which is connected to a corresponding canister  16  by means of a pipe  17  to feed the colorant, are disposed on a peripheral edge of the table  13  so as to be distributed substantially regularly along its whole circumference. 
     The rotation of the table  13  is achieved by means of motor means of a known type, for example by means of a direct current motor  19 , which is commanded by the control and processing unit  51 , in coordination with one or more specific delivery sequences. The motor can possibly be associated with one or more motor reducer devices. It is understood that the table  13  can be moved by means of a step motor, a brushless motor, a linear motor or by another type of suitable motor. 
     The device  10  also comprises a dispensing seating having a tray  56  disposed on a front of the frame  12  in which a container can be positioned, into which the colorants are delivered, according to said sequences and as will be described in more detail hereafter. 
     The pistons  21   a  to deliver the colorant are provided with a corresponding cylinder  23  ( FIGS. 2-5B ), a plunger  22 , mobile linearly inside the cylinder  23 . The plunger  22  is provided at an upper end with a head  22 , which protrudes from the cylinder  23  and is suitable to cooperate operatively with the actuation unit  40  in order to deliver the colorant by means of pumping. 
     Each piston  21   a  is associated with a corresponding delivery valve  30  disposed at a lower end of the piston  21   a,  hydraulically connected to the cylinder  23  and able to be selectively activated to intercept the flow of colorant. 
     The delivery valve  30  is of the disk type with three positions, and comprises a rotatable ring nut, solid with a disk type faucet  32  of the valve, provided with three attachment teeth  31  that protrude radially from the ring nut. The teeth  31  are angularly distanced in a manner coherent with the operating positions of the valve  30  as described below. The attachment teeth  31  are able to cooperate with the actuation unit  40  so as to allow the rotation of the disk and thus activate, or switch, the valve  30  between several operating positions. 
     In this case the valve  30  is in a closed position, used during the movement of the rotary table  13 , and in the step when the colorant is sucked up into the cylinder  23  when the dosing circuit, that is, the piston  21   a,  is disposed adjacent to the actuation unit  40 . The valve  30  can also be switched into a first open position with a limited flow rate and a second open position with a higher flow rate, in which positions the dosing circuit  21  is disposed adjacent to the actuation unit  40 . 
     Advantageously each valve  30  is also provided with mechanical end-of-travel stops, suitable to prevent the rotation of the disk type faucet  32  in unwanted positions. 
     The lower end of the piston  21  a is also stably coupled with an attachment element  33  provided with a sleeve  35  for connection to a corresponding pipe  17  and with a release lever  34 . The lever  34  allows to remove the piston  21   a  from its attachment seating on the table  13 , for example for maintenance requirements, at the same time closing the sleeve  35 , thus preventing any possible leakages of residual colorant when the piston  21   a  is removed. 
     The piston  21   a  is also provided with a metal tongue  25 , mounted on a lateral surface thereof, substantially facing toward the outside of the rotary table  13  so as to be facing toward the actuation unit  40  when it is disposed in correspondence with the actuation unit. The tongue  25  is able to cooperate with a proximity sensor  45  connected to the control and processing unit  51 , as will be described in more detail hereafter, so as to drive the rotation of the table  13  by means of said motor, provided with a bidirectional position encoder  20 , to position a predetermined dosing circuit  21  in correspondence with the actuation unit  40 . 
     Advantageously at least one tongue  25  has transverse sizes that are different from the other tongues  25 , so as to allow to identify a predetermined piston  21   a  and therefore a corresponding reference position. The piston  21   a  is assigned a number that identifies it univocally, starting for example from number one. The remaining pistons  21   a  are identified with different identification numbers, for example by progressively increasing the identification numbers of the other pistons  21   a  recognized by the sensor  45 . 
     The actuation unit  40  ( FIG. 1 ) is operatively positioned, as will be described hereafter, on a front part of the frame  12 , substantially in a median position, and comprises a first  41  and a second actuator  46 . The first actuator  41  comprises a compound lever unit driven for example by a step motor  42 , in turn commanded by the control and processing unit  51 . The compound lever unit is provided with a rotary actuation joint  43  having horizontal lever elements  44  that protrude radially with respect to a substantially vertical axis of rotation. The lever elements  44  are disposed angularly in a manner coherent with the teeth  31  of the valve  30 . In fact, the actuation joint  43  is suitable to cooperate, by means of the lever elements  44 , with the teeth  31  of the valve  30  when the piston  21  a is disposed adjacent to the actuation unit  40 , to command the activation of the valve between its operating positions. 
     The first actuator  41  is also associated with a proximity sensor  45 , such as for example an inductive sensor, connected to the control and processing unit  51  and mounted on a support plate  45   a  so as to face toward the rotary table  13 . The sensor  45  is able to cooperate with the tongues  25  of the pistons  21   a  so as to allow to detect, during the rotation of the table  13 , the alignment of the first actuator  41  and a corresponding piston  21   a.    
     The second actuator  46 , substantially aligned with the first actuator  41  in a position above it, comprises a container  46   a,  shaped like an elongated parallelepiped, open on one side. The actuator  46  comprises a step motor  46   b , attached above the frame  46   a,  and suitable to move linearly a slider  47  along part of the height of the frame  46   a.    
     The slider  47  is suitable to move, in turn, the plunger  22  of a piston  21   a  disposed adjacent to the actuation unit  40 . The slider  47  is mechanically coupled with a worm screw  48  that develops along the height of the frame  46   a,  in turn coupled at an upper end with the step motor  46   b.  The slider  47  comprises two horizontal protuberances  47   a,  able to cooperate operatively, during the movement of the slider  47 , with the head  22   a  of the plunger  22 , in order to take in/deliver colorant into/from the piston. A detection card  49  is also attached to the container  46   a,  and is able to detect a reference position, or zero position, of the slider  47 . According to a preferential embodiment, the card  49  comprises an optical type detector able to detect, through a groove  49   a  in a wall of the container  46   a,  a reference element of the slider  47 . 
     Advantageously, the command board  50  is hinged to the support frame  12  and is mobile between at least an open position to allow maintenance to the device, and a closed operating position. The first actuator  41  and the second actuator are mounted on the command board  51  so as to be adjacent to at least one delivery unit  21  positioned in the delivery seating when the command board  50  is disposed in the closed position. 
     Each canister  16  ( FIGS. 9-10A ) comprises a container  60  provided with a lid  61  to close its upper end, able to be driven by means of a handle  61   a  so as to effect filling operations and transfer the colorant inside it. The container  60  is also provided, at a lower end, with columns  62  to attach the canister  16 , suitable to be inserted into suitable seatings of the table  13  so as to hold each canister  16  firmly in a substantially vertical operating position. 
     The stirrer  64  is disposed inside the container  60 , and comprises an oblong rod  64   a  disposed axially along the height of the canister  16 . The rod  64   a  is provided with stirrer blades  65  suitable to mix the colorant contained in the canister  16 . The blades  65  are substantially flat or with a slightly curvilinear profile and protrude radially from the rod  64   a,  uniformly along its longitudinal development. The rod  64   a  is suitable to rotate axially, according to an axis of rotation that is substantially parallel to the axis of rotation X of the rotary table  13 . 
     The canister  16  is also provided with a direct current motor  66 , mounted on a lower end of the container  60 . The motor  66  is mechanically connected to the rod  64  so as to drive its rotation. 
     The device  10  also comprises an electronic card  70 , attached to the rotary table  13 , substantially in a central position, and electrically connected both to the control and processing unit  51  and also to a source of electric power, in a known manner, for example by means of sliding contacts disposed in the lower part of the table  13 . 
     The electronic card  70  is provided with a plurality of electric connectors  71 , each suitable to be connected by an electric feed cable  72  to an associated motor  66  of a canister  16 . Advantageously the electronic card  70  is provided with a micro-processor unit  70   a,  having digital outputs that are independently drivable and connected, directly or indirectly, to said connectors  71 . 
     The delivery device  10  as described heretofore functions as follows. 
     After positioning a container in the tray  56  of the dispensing seating, the control and processing unit  51 , according to the type of formula or composition of colorant to be obtained, and therefore according to a specific sequence of doses taken from a predetermined group of canisters among those available on the table  13 , activates the rotation of the table  13  until, by means of the proximity sensor  45 , the piston  21   a  required in the specific formula or composition is identified. 
     The control and processing unit  51  rotates the table  13 , continuously detecting its position with respect to the reference position by means of the bidirectional encoder  20 , until it disposes the piston  21   a  relating to the first colorant to be dosed in correspondence with the dispensing seating. This condition is detected when the proximity sensor  45  aligns with the tongue  25  of said piston  21   a . In the dispensing position the head  22   a  of the plunger  22  is disposed between the protuberances  47   a  of the slider  47  of the second actuator  46  ( FIG. 8A ). 
     It is also advantageously possible to define a procedure able to recognize the number of delivery units  21  present and mounted and their position with respect to a specific reference unit  21 . The table  13  is driven in a predetermined direction of travel, for example clockwise, and for every delivery unit  21  present, detected by the proximity sensor  45 , the distance in encoder steps is read, starting from the first unit  21  found and the size of its tongue  25 . 
     When the table has made a complete turn, the presence is also detected of the reference delivery unit  21  and consequently all the distances in encoder steps of the remaining delivery units  21  from the specific reference delivery unit are calculated and memorized. 
     Advantageously the control and processing unit  51  is connected to a memorization unit  52  in which at least a configuration table is memorized, which identifies the position of each piston  21   a  on the table  13  and the specific colorants contained therein. The configuration table can be modified according to possible variations and/or replacements of canisters  16  having different colorants. 
     During the rotation of the table  13 , all the valves  30  are disposed in their inactive position in which the teeth  31  are disposed so as not to interfere mechanically with the lever elements  44  of the compound lever unit of the second actuator  46 . 
     Subsequently the control and processing unit  51  switches the valve into its closed position, driving the motor  42  of the first actuator  41 . This causes the rotation of the actuation joint  43  so as to make a first of said lever elements  44  contact one of the teeth  31  of the valve  30 , producing the rotation of the disk type faucet  32 . 
     Then an intake step is activated ( FIG. 8B ) in which the colorant is taken from the corresponding canister  16  by means of the pipe  17  and transferred inside the piston  21   a.  In this step the plunger  22 , in an initial inactive step, that is, disposed completely inside the cylinder  23 , is lifted by means of the second actuator  46  to a predetermined loading position. This position corresponds to the intake of a quantity of desired colorant so as to obtain the desired composition. 
     In this case, the control and processing unit  51  activates for example the step motor  46   b  for a number of steps sufficient to move the slider  47  by means of the screw  48  to the desired position. In turn the slider  47  intercepts the head  22   a  of the plunger  22  by means of the lower protuberance  47   a  and causes it to be lifted. 
     At the end of the intake step, a pre-delivery step is carried out in which the control and processing unit  51  inverts the direction of rotation of the step motor  46   b  and therefore the direction of movement of the slider  47 , displacing the plunger  22  downward by a predetermined height, keeping the delivery valve  30  closed. This allows to obtain an optimum pressure condition inside the piston  21   a  for the subsequent delivery of the colorant. 
     When the plunger  22  has stopped moving, the control and processing unit  51  switches the valve into one of the two open positions, depending on the flow rate ( FIGS. 8B and 8C ), driving for example the motor of the first actuator  41 . This leads to the rotation of the actuation joint  43  so as to make a second and/or a third of said lever elements  44  contact the teeth of the valve  30 , rotating the disk faucet  32  of the valve  30  until it is open. The selection of one of the two positions, respectively with a greater or lesser flow rate, is carried out according to the quantity of colorant to be delivered, which is in turn directly proportional to the speed of movement of the plunger. 
     Subsequently the delivery step is effected, in which the control and processing unit  51  moves the slider  47  downward, as previously described, delivering the colorant through a hole of the disk type faucet  32  into the container below. 
     When the delivery step is finished, the control and processing unit  51  switches the valve  30  to its closed position, rotating the actuation joint  43  as described above so as to make the lever elements  44  contact the teeth  31  of the valve  30 , producing the rotation of the disk faucet  32  to its closed position and the first actuator  41  to its inactive position. 
     Then the control and processing unit  51  activates the rotation of the rotary table  13  so as to position in the dispensing seating the piston  21   a  corresponding to the next colorant to be delivered. The rotation of the table  13  is accurately controlled by the control and processing unit  51 , according to the information arriving from the encoder  20  and to the detection of the position of each piston  21   a,  provided by the sensor  25  together with the information to configure the disposition and content of the canisters  16  as memorized in the memorization unit  52 . 
     Advantageously the control and processing unit  51 , in correspondence with each individual delivery, regulates the rotation of the table  13  in the two directions of rotation, clockwise and anticlockwise, so as to minimize the total travel, that is, the absolute angle of rotation obtained as the sum of the individual angles of rotation of the table  13  during the delivery sequence of the final composition or formula. Since the speed of rotation of the table  13  is substantially constant, this allows to considerably reduce the overall delivery times, given the same formula sequence, compared with devices that always rotate in the same direction of rotation. 
     The optimization of the rotation sequences corresponding to the delivery sequences is effected according to the number of encoder impulses detected by the control and processing unit  51 . 
     During the functioning of the device  10 , that is, both during the rotation of the table  13  and also during the dispensing of the colorant, the control and processing unit  51 , by means of the microprocessor unit  70   a,  selectively activates, independently of the movement of the rotary support and/or its direction of rotation, one or more stirrers  64 , driving the corresponding motors  66 , so as to keep the colorant contained therein in good conditions of preservation. 
     It is understood that the drive of the stirrers  64  can be carried out by driving the corresponding motors  66  according to predetermined or variable groupings. According to another solution it is possible to define predetermined groupings of canisters  16 , in which a corresponding motor is associated with each grouping and is suitable to transmit, by means of associated transmission kinematisms, the rotation motion to all the stirrers  64  of the grouping. 
     The stirrers  64  are driven continuously or periodically, with predetermined or variable durations of stirring depending on the type of colorant contained in each canister  16  and/or a predetermined delivery sequence to be carried out. 
     In this way it is possible to mix the fluid contained in each container when actually desired, according to the type of fluid contained, not only during the movement of the rotary support, as happens in the state of the art, but also during the delivery of fluid or during periods of inactivity of the device. 
     According to a preferential solution, when the device  10  is switched on, or after any maintenance, such as the replacement of one or more delivery units  21 , an initialization step is performed in which the slider  47  is taken to an upper position, substantially at its upper end-of-travel. The table  13  is rotated to take a piston  21   a  to the delivery seating. The slider  47  is lowered, and by means of a thrust exerted by the lower protuberance  47   a  of the slider  47  on the head  22   a,  the plunger  22  is lowered until the lower end-of-travel is reached. The delivery valve  30  is closed and the actuation joint  43  is taken to an inactive position. Subsequently, the slider  47  is returned to the upper end-of-travel. 
     These operations are performed for all the pistons  21   a  present. 
     When this step is finished in which all the plungers  22  are at a lower mechanical abutment, the table  13  is rotated so as to free from the delivery zone any piston  21   a  possibly fouled and the slider  47  is taken to the ideal position so as to attach the head  22   a  of the plunger  22 . 
     It is clear that modifications and/or additions of parts and/or steps may be made to the delivery device  10  and the relative method as described heretofore, without departing from the field and scope of the present invention. 
     For example, it comes within the field of the present invention to provide that the device is provided with a device to clean the valve  30 , able to clean, during the rotation of the table  13 , any residual colorant from the lower surface of each valve  30 . This allows to keep the device  10  always in efficient conditions, reducing maintenance operations to a minimum. 
     It is also clear that, although the present invention has been described with reference to some specific examples, a person of skill in the art shall certainly be able to achieve many other equivalent forms of delivery device and the relative method, having the characteristics as set forth in the claims and hence all coming within the field of protection defined thereby.