GB2356397A - Pneumatically operated mechanism for an I.S. glass moulding machine - Google Patents

Abstract

A mechanism for an I.S. machine includes a pneumatically operated cylinder 18 and a pneumatic supply manifold 24 connected to the pneumatically operated cylinder via an electrically controlled proportional valve 22 which will set a pressure which is a function of the electrical input. A control means is provided for operating the cylinder 18 including means 30, 36 for supplying an electrical input to the proportional valve 22 having a first value for a first period of time so that a first pressure is applied to the cylinder 18 for a first predetermined period of time, and for supplying an input of a second value for a second period of time so that a second pressure is applied to the cylinder 18 for a seconds predetermined period of time. The mechanism may be for displacing a baffle from its retracted to its advanced state in contact with a mould. The baffle may include a body (50, fig 3) having a cup shaped portion (52) at the bottom and a piston having a cylindrical head (66) both adapted to sealingly engage a blank mould. Further the baffle may have a slidable tubular rod (62) secured to a collar (74) which is displaced by the pneumatically operated cylinder 18.

Description

2356397 BAFFLE MECHANISM OR OTHER MECHANISM FOR AN I.S. MACHINE The

present invention relates to machinery for manufacturing glass containers, such as an I.S. (individual section) machine, and more specifically to a mechanism, for example a baffle mechanism for that machine which closes the open top of a blank mold at the blank station to 5 define an escape path for air within the mold during parison formation.

An I.S. (individual section) machine has a plurality of identical sections (a section frame in which and on which are mounted a number of section mechanisms) each of which has a blank station which receives one or more gobs of molten glass and forms them into parisons having a lo threaded opening at the bottom (the finish), and a blow station which receives the parisons and forms them into bottles standing upright with the finish at the top. An invert and neck ring holder mechanism which includes an opposed pair of arms, rotatable about an invert axis, carries the parisons from the blank station to the blow station, inverting the parisons from a finish-down to a finish-up orientation in the process. A bottle formed at the blow station is removed from the section by a takeout mechanism.

The blank station includes one or more blank molds, each comprising opposed pai rs of blank mold halves or segments. These mold halves are displaceable between open (separated) and closed positions. The or each blank mold, when its halves are closed, is open at the top, and a track delivers a gob, by gravity, down to a position vertically above the open mold. Where the bottle to be formed is not circular in cross section (square for example) a funnel, which has a square passage, can be displaced into position over the open top of the blank mold to direct the gob into the mold, slightly changing its shape in the process. With the gob in the blank mold, a baffle of a baffle mechanism can be displaced down onto the funnel to supply air under pressure to the blank mold to "settle" the gob in the blank mold. The funnel and baffle are then removed and the baffle is repositioned on top of the open blank mold. Now, either counterblow air is introduced into the mold to blow the gob into the mold (a blow and blow 2 machine) or a plunger is advanced to press the gob into the mold (a press and blow machine). Air trapped between the outer surface of the gob and the inner surface of the blank mold will be forced out of suitable notches, in the bottom surface of the baffle. When the parison has been formed, the -5 baffle wil.1 be removed as the blank mold opens, and the parison will be transferred to the blow station. When a gob doesn't have to be shaped, the funnel may be dispensed with and the baffle may be immediately positioned on top of the blank mold to start the settling process.

In a state of the art baffle of this type, a central piston hangs from lo the bottom of the baffle to define a large central opening for settle air. When counterblow occurs the upward movement of the gob engages and pushes this piston upwardly to its home position where the bottom of the piston is flush with the bottom surface of the baffle. Bottles made in this way have a visible circular ridge on the bottom of the bottle and this is 1-5 undesirable.

It is accordingly an object of this invention to provide an improved pneumatically operated mechanism such as a baffle mechanism.

According to the present invention, there is provided a mechanism for an I.S. machine, comprising a pneumatically operated cylinder, pneumatic supply means connected to said pneumatically operated cylinder including an inlet conduit and an electrically controlled proportional valve which, upon receiving a variable input, will set a pressure which is a function of the input, a control for operating said pneumatically operated cylinder including means for supplying an input having a first value for said electrically controlled proportional valve for a first period of time selected so that a first pressure will be applied to the cylinder for a first predetermined period of time, and means for supplying a second input for said electrically controlled proportional valve for a second period of time selected 3 so that a second pressure will be applied to the cylinder for a second selected period of time.

In one embodiment of the present invention, the mechanism is a baffle mechanism for an I.S. machine having at least one section including a blank station having at least one blank mold, with the blank mold being open at the top and including inner and outer annular top sealing surfaces, the baffle mechanism comprising a baffle including a body having a cup shaped portion open at the bottom, and having a cylindrical side wall having a cylindrical inner surface, a generally vertical cylindrical bore lo extending through the top of the cup shaped portion, and the bottom of the cylindrical side wall having an annular bottom sealing surface for sealingly engaging the blank mold outer annular top sealing surface, and a tubular sleeve communicating with the vertical cylindrical bore and extending generally vertically upwardly from the top of the cup shaped portion.

The baffle mechanism further comprises a piston having a cylindrical head including a top surface, an annular sealing surface for sealingly engaging the cylindrical inner surface of the cup shaped portion and an annular surface on the bottom of the cylindrical head for engaging the inner annular top sealing surface of the blank mold, the annular surface on the bottom of the cylindrical head having a plurality of radial notch means extending across the bottom thereof. A tubular rod extends generally vertically upwardly from the top surface of the cylindrical head for slidable displacement in the tubular sleeve, and a collar is secured to the top of the rod. A spring is compressively located between the collar and the top surface of the cup shaped portion for urging the cylindrical head generally vertically upwardly relative to the cup shaped portion to a position whereat the cylindrical head top surface is adjacent or engages the top of the cup shaped portion.

A baffle support is secured to the collar and is displaceable from a retracted position whereat the baffle is remote from the blank mold, downwardly towards an advanced position whereat the baffle is located on 4 top of the blank mold.

The pneumatically operated cylinder is operable to displace said baffle support from the retracted position towards said advanced position.

The pneumatic supply means is connected to the pneumatically operated 5 cylinder, for initially supplying a relatively high pressure to the pneumatically operated cylinder which is sufficient to displace the collar generally vertically downwardly to a first location whereat the annular bottom sealing surface of the body sealingly engages the outer annular top sealing surface lo of the blank mold and the cylindrical head annular bottom surface engages the blank mold inner annular sealing surface, for then supplying a lower pressure to the pneumatically operated cylinder so that the collar will displace generally vertically upwardly to a second location whereat the annular bottom sealing surface of the body sealingly engages the outer annular top sealing surface of the blank mold and a predetermined distance separates the cylindrical head annular bottom surface and the blank mold inner annular sealing surface, and for finally again supplying a higher pressure to the pneumatically operated cylinder to displace the collar generally vertically downwardly to the first location whereat the annular bottom sealing surface of the body sealingly engages the outer annular top sealing surface of the blank mold and the cylindrical head annular bottom surface engages the blank mold inner annular sealing surface.

Passage means in said cylindrical head interconnect the interior of the tubular rod and the cylindrical head annular bottom surface so that when the piston is located at the second location, settle air can be directed through the tubular rod and passage means and through the annular separation between the cylindrical head annular bottom surface and the blank mold inner annular sealing surface into the blank mold and so that when the piston is located at the first location, air from the blank mold can flow out through the notch means through the passage means and into the tubular rod.

Reference will now be made to the accompanying drawings which illustrate a presently preferred embodiment incorporating the principles of the invention, and in which FIG. 1 shows, schematically, a baffle mechanism with a pressure regulating control valve made in accordance with the teachings of the present invention; FIG.2 is a graph of pressure versus time illustrating the operation of the control for the baffle mechanism according to the invention; FIG.3 is an elevational cross sectional, view showing a baffle above lo a blank mold of the I.S. machine; FIG.4 is a view similar to figure 3 showing a baffle engaging a blank mold in a first condition; and FIG. 5 is a view similar to figure 3 showing a baffle engaging a blank mold in a second condition.

FIG. 1 shows schematically a pneumatically operated baffle mechanism for use in a section of an I.S. machine. A carrier arm 2 that supports three baffles 4 (a triple gob machine) is connected to a vertical actuating rod 6. The actuating rod 6 has attached to it a piston 8 and the actuating rod extends downwardly through the piston into a cam housing 10. The lower end of the actuating rod 6 includes a cam follower 12, in the form of a roller, which rides in a barrel cam 14 defined in the wall 16 of the cam housing 10. This actuating rod will be elevated and rotated during the uppermost portion of its elevation so that the baffle arm can be displaced between an elevated retracted position away from the center of the blank molds and a lowered advanced position where the axes of the blank molds will be coaxial with the axes of the closed blank molds and will be located on top of the blank molds. A pipe 20, which represents cylinder-down air, leads from the cylinder 18 to a manifold 24 which provides a source of compressed air at a pressure. of 3 to 4 bar.

An' electronically settable pressure regulating control valve 22, which is an electropneurnatic valve, is located in the pipe 20 between the cylinder 18 and the manifold 24. The control valve 22 is an electrically controlled 6 proportional valve and comprises an electronic control 26 connected by a wire 28 to a device 30 such as a potentiometer for defining a set point.

Connected to the potentiometer 30 is a display panel 32. Wires 34 connect the potentiometer 30 to a machine controller 36 which acts as a timing control providing timing pulses to the potentiometer 30 which is powered by a power supply 40 via wires 38. The electronic control 26 of the control valve 22 is connected by wires 42, 44 to a display in the form of a production line console 46 and to a 24 volt power supply 48. The electronic control 26 is so constructed that, on receiving a control voltage lo from the potentiometer 30, it translates it into a control signal which equates to a pressure.

The production line console 46 displays the pressure versus time curve generally as shown in FIG.2. Stored in memory in the production line console 46 is a desired curve, and both the actual curve and the desired curve can be displayed so that adjustments of the potentiometer settings can be made to conform these curves.

Each baffle of the baffle mechanism (FIG.3) has a body 50 which includes an inverted cup shaped portion 52 having an annular inclined sealing surface 54 extending around its open bottom for engaging and sealing a corresponding top surface 56 of a blank mold 57 open at the top. The body 50 also includes a vertical tubular sleeve portion 58 which defines a cylindrical bearing surface 60 for slidably receiving the rod 62 of a piston element 64. The cylindrical head 66 of the piston element 64 has an annular sealing surface 68 which is slidingly displaceable within the bore 70 of the cup shaped portion 52. A spring 72, which is located around the vertical tubular sleeve portion 58, is compressed between a collar 74 which is releasably secured to the carrier arm 2 and which is secured to the piston rod 62 and the top of the cup shaped portion 52, to maintain the top surface of the cylindrical head 66 in engagement with the adjacent surface of the cup shaped portion when the baffle is separated from the blank mold.

FIG.2 shows the operation of the control with the resultant pressures 7 supplied by the control valve 22 as controlled by the electronic control 26.

The cycle begins with a first timing pulse at TO from the machine controller 36. At TO, the control valve 22 is turned on and the control valve 22 is set to supply a high pressure P1 to the cylinder 18. From TO to T1, the friction and inertia of the piston 8, the actuating rod 6, and the carrier arm 2 is overcome while the pressure reaches P1. From T1 to T2, this pressure provides the force required for quick and consistent operation to move the baffles down and onto the closed blank molds as shown in FIG. 4, where the inclined annular sealing surface 54 of the cup shaped portion engages lo the corresponding surface 56 on the blank molds and the annular flat bottom surface 78 of the piston member 64 engages the corresponding surface 76 of the blank molds (these mating surfaces may also be inclined such as would be the case where loading into the blank mold is difficult and the top of the blank mold begins with an inclined annular surface to assist loading). At T2, the control valve is set to supply a second lower pressure P2 (which for example could be 25% less than P1) so that the force provided by the pressure on the piston 8 is enough to maintain surfaces 54 and 56 in engagement but is not enough to maintain surfaces 76 and 78 in engagement. P2 is selected so that the collar 74 will retract upwardly until the top of the spring 72 is compressed to a length "L" which will establish a separation X between surfaces 76 and 78 (FIG. 5). Now settle air introduced into the blank mold through the central bore 80 in the piston rod will pass -through a number of radially extending holes 82 in the cylindrical head into a corresponding number of vertical holes 84 and through the annular gap between the annular bottom surface 78 of the cylindrical head and the top surface 76 of the blank mold (suitable relief holes 88 which connect the interior of the body to atmosphere assure that the cylindrical piston head 66 can move smoothly relative to the body 50). When settle blow is complete (T4) and the gob is to be formed into a parison, the control will again set the pressure at P1, which is reached at T5 to further displace the collar 74 downwardly until the bottom annular sealing surface 78 of the cylindrical head forcefully engages (and through most of its circumferential extent seals against) the top surface 76 of the blank mold to close the blank mold (FIG. 4). As the parison is formed (forced to fill the internal cavity defined by the inner surface 90 of the blank mold and the bottom surface 92 of the cylindrical piston head) air can escape from the top of the mold, as indicated by the arrows through a number (four in the preferred embodiment) of small radially extending notches (not shown) defined in the bottom annular surface 78 of the cylindrical head into the vertical holes 84, through the radial holes 82, into the piston rod bore 80 and out through now exposed escape bores 96, into the space between the lo top of the piston and the cup shaped portion 52, and out the relief holes 88. The pressure P1 is held until T6 (which may be the end of the application of counterblow) when the second timing pulse occurs to turn the control valve off and the pressure goes to zero so that the baffle mechanism may be removed from the mold guided by the barrel cam 14.

9 CLA1 MS 1 A mechanism for an I.S. machine, comprising a pneumatically operated cylinder, pneumatic supply means connected to said pneumatically operated cylinder including an inlet conduit and an electrically controlled s proportional valve which, upon receiving a variable input, will set a pressure which is a function of the input, a control for operating said pneumatically operated cylinder including means for supplying an input having a first value for said electrically controlled proportional valve for a first period of time selected so that a first pressure will be applied to the cylinder for a first predetermined period of time, and means for supplying a second input for said electrically controlled proportional valve for a second period of time selected so that a second pressure will be applied to the cylinder for a second selected period of time.

2. A mechanism for an I.S. machine according to claim 1, wherein said mechanism is a baffle mechanism and said baffle mechanism is displaced from a retracted position to an advanced position while said first input is supplied to said electrically controlled proportional valve.

3. A mechanism for an I.S. machine according to claim 2, wherein said control supplies said second input to said electrically controlled proportional valve after said baffle mechanism has been displaced to the advanced position and said second pressure is less than said first pressure.

4. A mechanism for an I.S. machine according to claim 3, wherein said control supplies said first input to said electrically controlled proportional valve for a third period of time after the expiration of the second selected period of time.

5. A mechanism according to any of claims 2 to 4, wherein said baffle mechanism is a baffle mechanism for an I.S. machine having at least one section including a blank station having at least one blank mold, with the blank mold being open at the top and including inner and outer annular top sealing surfaces, comprising:

a baffle including a body having a cup shaped portion open at the bottom, and having a cylindrical side wall having a cylindrical inner surface, a generally vertical cylindrical bore extending through the top of the cup shaped portion, and the bottom of the cylindrical side wall having an annular bottom sealing surface for sealingly engaging the blank mold outer annular top sealing is surface, and a tubular sleeve communicating with said generally vertical cylindrical bore and extending generally vertically upwardly from the top of said cup shaped portion, a piston having a cylindrical head including a top surface, an annular sealing surface for sealingly engaging the cylindrical inner surface of said cup shaped portion and an annular surface on the bottom of said cylindrical head for engaging the inner annular top sealing surface of the blank mold, said annular surface on the bottom of said cylindrical head having notch means extending across the bottom thereof, a tubular rod extending generally vertically upwardly from the top surface of said cylindrical head for slidable displacement in said tubular sleeve, and a collar secured to the top of said rod, a spring compressively located between said collar and the top surface of said cup shaped portion for urging said cylindrical head generally vertically upwardly relative to said cup shaped portion to a position whereat said cylindrical head top surface is adjacent or engages the top of said cup shaped portion, and a baffle support secured to said collar and displaceable from a retracted position whereat the baffle is remote from the blank mold, downwardly towards an advanced position whereat the baffle is located on top of the blank mold, the pneumatically operated cylinder being operable to displace said baffle support from said retracted position towards said advanced position, and the pneumatic supply means being connected to said pneumatically lo operated Pylinder, for initially supplying a relatively high pressure to said pneumatically operated cylinder which is sufficient to displace said collar generally vertically downwardly to a first location whereat said annular bottom sealing surface of said body sealingly engages the outer annular top is sealing surface of the blank mold and said cylindrical head annular bottom surface engages the blank mold inner annular sealing surface, for then supplying a lower pressure to said pneumatically operated cylinder so that said collar will displace generally vertically upwardly to a second location whereat said annular bottom sealing surface of said body sealingly engages the outer annular top sealing surface of the blank mold and a predetermined distance separates said cylindrical head annular bottom surface and the blank mold inner annular sealing surface, and for finally again supplying a higher pressure to said pneumatically operated cylinder to displace said collar generally vertically downwardly to said first location whereat said annular bottom sealing surface of said body sealingly engages the outer annular top sealing surface of the blank mold and said cylindrical head annular bottom surface engages the blank mold inner annular sealing surface, passage means being provided in said cylindrical head interconnecting the interior of said tubular rod and the cylindrical head.

annular bottom surface so that when said piston is located at said second location, settle air can be directed through said tubular rod and passage 12 annular bottom surface so that when said piston is located at said second location, settle air can be directed through said tubular rod and passage means and through the annular separation between said cylindrical head annular bottom surface and the blank mold inner annular sealing surface into the blank mold and so that when said piston is located at said first location, air from the blank mold can flow out through said notch means through said passage means and into said tubular rod.

6. A baffle mechanism for an I.S. machine according to claim 5, wherein radially extending holes are defined in said cup shaped portion proximate the top of said cylindrical inner surface so that air can enter or leave said cup shaped portion as said cylindrical head is displaced relative to said body.

7. A baffle mechanism for an I.S. machine according to claim 6, wherein hole means is defined in said tubular rod which will communicate with the space between the top surface of said cylindrical head and said cup shaped portion when said cylindrical head is at said first location so that air from the blank mold can pass from said passage means through said tubu lar rod, through said tubular rod hole means and out through the radially extending holes in said cup shaped portion.

8. A baffle mechanism for an I.S. machine according to claim 5, 6 or 7, wherein said pneumatic supply means comprises an electropneurnatic valve which can define either said high pressure or said low pressure.

9. A mechanism for an I.S. machine according to claim 1, substantially as hereinbefore described with reference to the accompanying drawings.