ES2199495T3 - ASPIRATION GRIP DEVICE. - Google Patents

Abstract

GRIPPING UNIT FOR SUCTION (7) THAT HAS AN ASPIRATION HEAD (15) IN WHICH A CAVITY (18) PERMANENTLY CONNECTED OUTSIDE IS DEFINED THROUGH A PASSING HOLE (23) AND CONNECTED TO A SUCTION PUMP (14) THROUGH A DUCT (20) CONTROLLED BY A VALVE (22) SITUATED INSIDE THE SET (20) AND NEXT TO THE CAVITY (18).

Description

Suction grip device.

The present invention is related to a immobilization unit by suction.

In the description that follows, a specific reference, purely by way of example, to the sector of cigarette packaging and in particular to the unit of immobilization by suction to supply payroll in the cigarette packing machine.

It is known that the packaging machines of cigarettes employ suction immobilization unit to be transporting the forms successively between the station collection of the forms, located in their warehouse, and the supply station where the forms are transferred to the  respective seats on the packing wheel.

The immobilization units by suction known comprise a wheel that supports several heads of suction, in each of which there is defined a cavity that communicates on one side with the outside environment through a through hole controlled by the first valve, and connected in the other side with a suction head discharge pump by a conduit controlled by the second valve that is normally in the duct at a certain distance from the cavity. In the known immobilization units, the two valves are normally incorporated in a simple valve slide.

To retain a return in the head of immobilization, the head comes into contact with the form that close the cavity to define, with the cavity, a chamber of suction in which the vacuum is formed (relative to the pressure atmospheric) closing the first valve and opening the second. To release the form, the atmospheric pressure in the suction chamber by opening the first valve and closing the second.

The response time of the unit immobilized, that is, the time needed to activate and deactivate the suction force, depends on the total volume of the suction chamber, suction pump performance and size of said passage hole; being the total volume of the suction chamber equal to the volume of the cavity plus the volume of the part of the duct between the cavity and the second valve.

The first valve becomes necessary using the suction head discharge pump characterized by a relatively high discharge head and a relatively low flow rate, and it could not work properly having to withstand large load losses such as those would be induced by the hole if it were not closed during suction through the first valve.

US Patent 4009876 presents a unit for the delivery of corrugated sheets to the machine Printing and package formation. The feeding mechanism includes a perforated suction head to move the leaves individual picking them up from a pile of leaves and carrying them to the machine; the suction head includes a perforated plate and an impending chamber mounted on a tubular element that is received telescopically above the support element tubular with open ends, mounted on a hollow platform of reciprocal operation. A valve is arranged in the end of the tubular support platform to connect the platform to an evacuator supported with its front ends in the platform and at its opposite ends by an adjustable support universally to compensate for the spreadsheets. A valve discharge that unites the platform with the atmospheric environment is operable in a measure relative to the vacuum valve by means of a linear cam located adjacent to the platform.

Known units of the type mentioned above they have several drawbacks, the first one being the need to provide and control two separate valves or one slide valve relatively complicated for each head of suction. Even more in view of the location of the second valve, the suction chamber has a relatively large volume, which consequently produces a relatively slow response from the valve.

It is an objective of the present invention provide a suction immobilization unit designed to eliminate the aforementioned inconveniences and that in particular Out of low cost and easy to produce.

According to the present invention, a unit of immobilization by suction as defined in claim 1.

A non-limiting embodiment of the present The invention will be described by way of example with reference to accompanying drawings in which:

Figure 1 presents a cross-sectional view, with some parts removed for clarity, from one embodiment preference of the unit according to the present invention;

Figure 2 presents a section to scale more large along line II-II of Figure 1 of a detail of Figure 1 in two different positions operational;

Figure 3 presents a section along the line III-III of Figure 2;

Figure 4 is similar to Figure 2 and presents a detail of Figure 2 in a later operational position.

The number 1 in Figure 1 presents as a unit, the continuous packaging machine comprising a wheel propelled packer 2 that rotates continuously (in direction counterclockwise in Figure 1) around the respective axis (which is not proven) perpendicular to the plane of Figure 1, and in turn comprises several peripheral seats 3, spaced at equal and hollow distances (only one can be seen) to successively receive the respective cards 4 of card stock or similar pre-folded material. Machine 2 it also comprises a warehouse 5 for a stack 6 of sheets 4; Y a suction immobilization unit 7 interposed between the pickup station S1 at the open end 8 of the warehouse 5 and the supply station S2 on packing wheel 2, and for extract spreadsheets 4 from end 8 and carry them on to the respective seats 3.

The immobilization unit 7 comprises a propelled roller 9 that rotates continuously in the direction of the clockwise in Figure 1 around respective axis 10 central and fixed, parallel to the axle (not shown) of wheel 2 and perpendicular to longitudinal axis 11 of warehouse 5. Roller 9 it comprises an inner chamber 12 connected by conduit 13 to the suction pump 14, so-called `` side channel '' pump, for create in the chamber 12 a vacuum with respect to the atmospheric pressure of outside.

The roller 9 supports a number of heads of immobilization tires 15 distributed around the axis 10 and connected to roller 9 through the interposition of the respective arms 16. As shown more clearly in the Figure 2, each head 15 is substantially shaped like a plate which is connected on one side to the respective arm 16 and is defined on the other side by the immobilization surface 17 in which a cavity 18 is defined by an annular edge 19 and connected to the chamber 12 by a respective conduit 20 formed along the respective arm 16.

In the presented embodiment, the surface of immobilization 17 is substantially defined by the surface from above edge 19.

In the joint 21 that communicates the duct 20 with the respective heads 15, each conduit 20 has a valve 22 to control this duct 20, that is, to open or close the conduit 20 in order to connect or disconnect it from the respective cavity 18. The orifice 23 is formed in each head 15 so that each respective cavity 18 communicates permanently with the outside atmosphere.

Each valve 22 is a known mechanical valve and comprises a head 24, an annular seat 25 held by the head 24 and formed in the respective seal 21 and a bar of control that is slidably adjusted axially to two perforated support walls 27 (Figure 3) located within the duct 20, and moves axially through a device of activation 28 and in a radial direction relative to axis 10, between the open position (Figure 2a) in which the cavity 18 is pneumatically connected to conduit 20 and therefore to the chamber 12, and the closed position (Figure 2b) in whose cavity 18 is pneumatically isolated from conduit 20 and therefore from the chamber 12.

The activation device 28 comprises a body 29 that is adjusted to the end of the respective bar 26 in front of the end connected to the respective head 24 and is adjusted to the roller 9 so that it can slide along with the bar 26 in the radial direction relative to the axis 10 and in this way move the bar 26 between said positions, open and closed. The activation device 28 comprises a spring 30, which is located radially with respect to the wall 31 defining the chamber 12 and coaxially with respect to the respective bar 26 and is compressed between the respective wall 27 and the body 29 to maintain normally the bar 26 in said position
closed.

The activation device 28 also comprises a cylindrical bar 32 that is adjusted to the body 29 to slide longitudinally with respect to body 29 along of the respective axis 33 parallel to the axis 10 and is adjusted so swivel at one end with a cooperating pusher roller 34 with the fixed cam 35. The cam 35 is formed in such a way that when the roller 9 rotates around the axis 10, the body 29 and by therefore the respective bar 26 of each head 15 moves in the radial direction with respect to axis 10, between said position open and the aforementioned closed position.

\hbox{Figura 2}

) en la que el rodillo 34 se junta con la leva 35 y la posición de reposo (Figura 4) en la que el rodillo 34 está separado de la leva 35. El dispositivo de activación 36 comprende un conocido accionador magnético 37 que, cuando está activado, mueve la barra 32 a lo largo del eje 33 desde la citada posición de trabajo a la citada posición de reposo; y el resorte 38 situado de manera coaxial con la barra 32 entre el cuerpo 29 y el rodillo 34 para mantener normalmente la barra 32 en la citada posición de trabajo.The movement of the bar 32 along the axis 33 is controlled by the activation device 36 to cut off the control of the respective valve 22 that moves the bar 32 between the working position (

 \ hbox {Figure 2} 

) in which the roller 34 joins the cam 35 and the rest position (Figure 4) in which the roller 34 is separated from the cam 35. The activation device 36 comprises a known magnetic actuator 37 which, when activated, moves the bar 32 along the axis 33 from said working position to said resting position; and the spring 38 located coaxially with the bar 32 between the body 29 and the roller 34 to normally keep the bar 32 in said working position.

As shown in Figure 1, each seat 3 it is formed on the outer surface 39 of the respective head 40 in front of the inside of the head 40 connected to the wheel 2 to be able to oscillate with respect to the wheel 2 around the axis 41 parallel to axis 10 under the control of a known device of rocker arm control not shown in the drawings. Each seat 3 has two side surfaces 42 inclined towards each other and towards the lower surface 43 crossed by a number of holes 44 through which a  known suction device (not presented in the drawings) is communicates with the outside

\hbox{Figura
2.}

The operation of an immobilization head 15 will be described with reference to the

 \ hbox {Figure
two.} 

To retain a sheet 4 on the surface of immobilization 17 of head 15, surface 17 enters substantial contact with form 4 that closes the respective cavity 18 to define, with cavity 18, a suction chamber in which the vacuum is formed (with respect to atmospheric pressure) by closing the respective valve 22 and connecting it manner said suction chamber to chamber 12 in which the Pump 14 maintains a constant vacuum.

Pressure losses caused by the orifice of step 23 permanently connected to the outside, do not present serious problems, the pump 14 being able to compensate even the relatively high load losses such as those induced by hole 23.

To release form 4, it is restored Automatically the atmospheric pressure inside the mentioned chamber suction through hole 23 by simply closing the valve 22.

The relatively small chamber volume of suction facilitates obtaining extremely fast response of the immobilization head 15 which, at the same time, is cheap and easy to produce since it comprises only one valve 22.

The operation of the immobilization unit 7 will be described with reference to Figure 1, in relation to a immobilization head 15 and at the time when the head 15 after having released form 4 within the respective seat 3 in the supply station S2 is moved by the rotation of the roller 9 towards the pickup station S1 to catch another form 4.

Between the S2 supply station and the station of collection S1, the valve 22 of the head 15 is maintained in the cited closed position.

As it is fed through the S1 station, the immobilization head 15 removes form 4 by contacting the end 8 of warehouse 5 and retains it by suction on the Immobilization surface 17. More specifically, in a moment given its movement, the immobilization head 15 is located with the immobilization surface 17 substantially contacting the contact end 8 of the return 4 and, just before arriving to this position, the activation device 28 moves the valve 22 within said open position to connect cavity 18 to chamber 12 and, through cavity 18, activate the force of suction causing the contact end 8 of the return 4 to adhere to the surface of immobilization 17.

While roller 9 rotates, head 15 leaves the collection station S1 from which form 4 has been withdrawn and takes it to supply station S2 where form 4 is deposited in the respective seat 3 of the respective head 40

At station S2, head 40 oscillates so known around the respective axis 41 moved by the known rocker arm device (not shown in the drawings) to remain for a certain period of time in front of the immobilization surface 17 of the head 15. During this time, head 15 is inserted into the seat 3 so that the immobilization surface is positioned so that it allows you to substantially contact the surface 43; and, just before it reaches this position, the device of activation 28 moves valve 22 to that position closed to cut the suction through the cavity 18, and the Suction through holes 44 on surface 43 are activated to release the form 4 inside the seat 3 to which it adheres by suction.

As you can see in Figure 1, the insertion of the head 15 inside the respective seat 3 facilitates folding of form 4 in a U along the respective preformed bending lines (not shown) when the return is  inserted into seat 3.

The operations mentioned above are repeated cyclically

To prevent form 4 from being introduced inside the seat 3, the respective head 15 must be avoided remove form 4 when it passes through station S1, function that is performed by the activation device 36 of the head 15. More specifically, along the head aisle 15, through station S1, the respective magnetic operator 37 remains activated to separate the roller 34 from the cam 35 and so prevent the respective valve 22 from being opened, so that, in absence of suction, immobilization surface 17, when pass through station S1, contact the form 4 at end 8 but do not remove it.

In another embodiment not shown, cavity 18 It is divided into several separate elementary cavities and kept pneumatically connected to each other by the perforated sections, and surface 17 is defined by the surface above edge 19 and by surface above the aforementioned sections to provide a support surface more great for payroll 4.

In addition, but it has not been presented in the drawings, the cavity 18 communicates permanently with the outside environment through a number of small holes 23 diameters

Claims (9)

1. A suction immobilization unit containing at least one head (15), at least one cavity (18) defined in said suction head (15) and the suction means (13, 14, 20) for create a vacuum within said cavity (18); the suction means (13, 14, 20) comprise a conduit (20) that communicates with said cavity (18), a pump (14) connected to said conduit (20), and a control valve (22) located along said conduit (20) between said pump (14) and said cavity (18); characterized in that in said pump (14) there is a side channel suction pump having the low discharge head and high flow rate, said valve (22) is located in the joint (21) that connects said conduit (20) to said suction head (15) to be in close proximity to the cavity (18), and at least one through hole (23) is formed in said suction head (15) to connect said cavity (18) permanently with the outside atmosphere. 2. A unit as claimed in the Claim 1, further comprising a propelled roller (9) which rotates around the fixed axis (10) and supports said head suction (15). 3. A unit as claimed in the Claim 1 or 2, wherein said valve (22) is a valve mechanical (22); the unit contains mechanical control means (28) to control the position of said valve (22). 4. A unit as claimed in the Claim 3, wherein said mechanical control means (28) comprise a cutting device (36) to cut the control of said valve (22). 5. A unit as claimed in the Claim 4, wherein said cutting device (36) it comprises a magnetic operator (37) to disconnect the roller of the pusher (34) of said cam (35). 6. A unit as claimed in the Claim 3, 4 or 5, wherein the mechanical control means (28) they comprise a bar (26) connected to said valve (22) and which it moves longitudinally to move the valve (22) between the open position and closed position, respectively, opening and closing said conduit (20). 7. A unit as claimed in any Claim 3 to 6, wherein said control means mechanics (28) also comprise a pusher roller (34) mechanically connected to said bar (26); and a fixed cam (35) held by said pusher roller (34) to move the said bar (26) cyclically in the axial direction. 8. A device for supplying the spreadsheets (4) to the packing wheel (2) that has several seats (3), each to receive said spreadsheet (4); The device comprises a collection station (S1) in the warehouse (5) for storing said sheets (4) and a supply station (S2) in said packaging wheel (2) being characterized by having a suction immobilized unit (7) as claimed in Claim 2; said propelled roller (9) feeding said suction head (15) through said collection station (S1) to remove said respective sheet (4) from said store (5), and through said station of supply (S2) take the aforementioned return (4) to the respective seat (3). 9. A device as claimed in the Claim 8, wherein said suction head (15) is formed to be inserted into said respective seat (3) in said supply station (S2) to double said payroll (4) in a U inside the seat (3).