Blow moulding machine with absorption refrigerator

Abstract

Blow moulding machine (1) for forming plastic containers from preforms, comprising: a plurality of blow moulds (11), each defining a respective blow moulding station, a pressure source (2) to provide the pressurization for blowing, a cooling unit (3) for cooling the moulds (11), said cooling unit comprising a cooling line (31) for conveying a coolant liquid, an absorption refrigerator (6) that works by recirculating at least one solution, comprising: a first high-pressure section (61) and a second low-pressure section (62), said second section (62) comprising an evaporator (621) for the low-pressure evaporation of at least one component of said solution, wherein said cooling line (31) defines said evaporator (621) of said second section (62) so that the heat from said low-pressure evaporation is released by said coolant liquid.

Description

Blow moulding machine with absorption refrigerator

[0001] The present invention relates to a blowing machine for producing plastic containers from preforms by blow moulding.

[0002] The use of plastic containers and the use of machines that produce the containers by blow moulding are known in the pourable-product packaging sector. Such machines require a pressure source to generate the pressure required for the blowing phase, as well as a cooling system to cyclically cool the moulds.

[0003] A blow moulding machine according to the present description and / or according to any one of the attached machine claims helps to improve the energy sustainability of the machine.

[0004] The features of a machine according to the present description are clarified in the detailed description below of an example embodiment of the machine.

[0005] The detailed description below relates to the attached drawings, in which:

[0006] -is a schematic top view of the machine.

[0007] The machine is designed to form plastic containers from preforms by blow moulding.

[0008] The machine comprises a plurality of blow moulds 11. Each mould 11 defines a respective blow moulding station. The machine 1 is a rotary machine and comprises a carousel on which the blow moulding stations are mounted.

[0009] The machine 1 comprises a pressure source 2 to provide the pressurization required for blowing. The pressure source comprises a compressor.

[0010] The machine 1 comprises a cooling unit 3 to cool the moulds 11. This cooling unit 3 comprises a cooling line 31 for conveying a coolant liquid. The direction of conveyance of the coolant liquid is indicated by the arrow A.

[0011] The machine 1 comprises an absorption refrigerator 6 that works by recirculating at least one solution. This solution for example comprises water, which is a refrigerant component of the solution, and lithium bromide, which is an absorbent component of the solution.

[0012] The absorption refrigerator 6 comprises a first high-pressure section 61 and a second low-pressure section 62. Said high pressure is greater than said low pressure. Each of said high pressure and said low pressure are in any case preferably below atmospheric pressure.

[0013] The second section 62 comprises an evaporator 621 for the low-pressure evaporation of at least one component of the solution. Said at least one component of the solution in this case corresponds to the refrigerant component.

[0014] The cooling line 31 defines the evaporator 621 of the second section 62 so that the heat from the low-pressure evaporation is released by the coolant liquid. As a result, the heat that is absorbed by said refrigerant component in the evaporator 621 of the second section 62 cools the coolant liquid. Consequently, given that the coolant liquid is used to cool the moulds 11 and defines the evaporator 621 of the second section 62 of the absorption refrigerator 6, the absorption refrigerator 6 is used efficiently to cool the moulds, thereby enhancing the energy sustainability of the machine 1.

[0015] The machine 1 comprises a heating line 41 to convey a liquid heated by a component of the machine 1. This component of the machine may for example be the compressor. The direction of conveyance of the heated liquid is shown by the arrow B.

[0016] The first section 61 comprises a generator 611 for the high-pressure evaporation of said refrigerant component of the solution. Said refrigerant component is for example water.

[0017] The heating line 41 defines the generator 611 so that the heat for said high-pressure evaporation is supplied by the heated liquid.

[0018] The machine 1 comprises a temperature lowering unit 5 positioned upstream of the compressor 2 to feed a temperature lowering liquid into the compressor 2 to cool the compressor 2. The heating line 41 is positioned downstream of the compressor to receive the temperature lowering liquid, so that the heated liquid corresponds to said temperature lowering liquid once the temperature lowering liquid has absorbed heat from the compressor 2. As a result, the heat produced by the compressor can be reused efficiently by the generator 611 of the absorption refrigerator 6. This further enhances energy sustainability since the heat from the compressor is used by the generator 611 of the absorption refrigerator 6.

[0019] The cooling unit 3 comprises a recirculation line 32 to recirculate a recirculation liquid through the moulds 11. The cooling unit 3 comprises a heat exchanger 33 interposed between the cooling line 31 and the recirculation line 32 so that the coolant liquid cools the recirculation liquid. As a result, the coolant liquid cools the moulds indirectly by interposing the recirculation liquid that is cooled by said coolant liquid.

[0020] The cooling unit 3 comprises a pump to recirculate the recirculation liquid.

[0021] The first section 61 also comprises a condenser 612 to condense said refrigerant component of the solution that has evaporated by means of the generator 611. The second section 62 also comprises an absorber 622 to condense said refrigerant component of the solution that has evaporated by means of the evaporator 621.

[0022] The cooling line 31 is also designed to recirculate the coolant liquid, which is recirculated along the cooling line 31 by a respective pump.

Claims

Blow moulding machine (1) for forming plastic containers from preforms, comprising:a plurality of blow moulds (11), each defining a respective blow moulding station,a pressure source (2) to provide the pressurization for blowing,a cooling unit (3) for cooling the moulds (11), said cooling unit comprising a cooling line (31) for conveying a coolant liquid,an absorption refrigerator (6) that works by recirculating at least one solution, comprising:a first high-pressure section (61) and a second low-pressure section (62), said second section (62) comprising an evaporator (621) for the low-pressure evaporation of at least one component of said solution,wherein said cooling line (31) defines said evaporator (621) of said second section (62) so that the heat from said low-pressure evaporation is released by said coolant liquid.Machine (1) according to Claim 1, comprising a heating line (41) for conveying a liquid heated by a component of said machine (1), wherein:said first section (61) comprises a generator (611) for the high-pressure evaporation of said component of said solution,said heating line (41) defines said generator (611) so that the heat from said high-pressure evaporation is supplied by said heated liquid.Machine (1) according to Claim 1 or 2, wherein said component of said machine (1) corresponds to said source (2).Machine (1) according to Claim 3, comprising a temperature lowering unit (5) positioned upstream of said source (2) to feed a temperature lowering liquid into said source (2), said heating line (41) being positioned downstream of said source (2) to receive said temperature lowering liquid so that said heated liquid corresponds to said temperature lowering liquid once said temperature lowering liquid has absorbed heat from said source (2).Machine (1) according to Claim 4, wherein said source (2) comprises a compressor.Machine (1) according to one or more of the preceding claims, wherein said cooling unit (3) comprises a recirculation line (32) for recirculating a recirculation liquid through the moulds (11), and a heat exchanger (33) interposed between said cooling line (31) and said recirculation line (32) so that said coolant liquid cools said recirculation liquid.Machine (1) according to any one of the preceding claims, wherein said component of the solution is a refrigerant component, for example water, and said solution also comprises an absorbent component, for example lithium bromide.

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