Patent Application
20110088879
The invention relates to an arrangement on a printing machine for the temperature control of operating points of the printing machine having different operating temperatures.
Different systems exist in the prior art, which bring or keep fluids, which are used on printing machines, or individual zones of printing machines to or at a specific temperature for the sake of temperature control.
For example, DE 4426077 describes a system with two refrigerating machines.
DE 10316860 and WO 2006072558 disclose systems with heat recovery.
In view of the increasing environmental awareness and the energy price development, further improvements of how to optimise the heat and mass transfer on printing machines further are still being searched for.
It is therefore an object of the invention to effectively control the temperature of the process heat, different operating points on a printing machine and to economically and ecologically use the process heat produced at the operating points.
The object is solved by the devices according to the independent claims. Advantageous embodiments are disclosed in the subclaims.
A first aspect of the invention relates to an arrangement on a printing machine, comprising at least one low-temperature temperature control point (NT temperature control point), at least one medium-temperature temperature control point (MT temperature control point), and at least one high-temperature temperature control point (HT temperature control point), which are arranged in a low-temperature zone (NT zone), a medium-temperature zone (MT zone), and at least one high-temperature zone (HT zone) of a printing machine and are designed such that the NT zone can be controlled to a low temperature by means of the NT temperature control point, the MT zone to a medium temperature by means of the MT temperature control point, and the HT zone to a high temperature by means of the HT temperature control point, the low temperature being lower than the medium temperature and the medium temperature being lower than the high temperature,
wherein the arrangement comprises a central heat exchange system designed such that the NT temperature control point, the MT temperature control point, and the HT temperature control point can be temperature controlled via the central heat exchange system, wherein a pipe system of the central heat exchange system can be flown through by a heat exchange fluid, and
wherein the heat exchange system is connected with the NT temperature control point, the MT temperature control point, and the HT temperature control point such that heat flows can be transferred between the NT temperature control point and the heat exchange fluid, between the MT temperature control point and the heat exchange fluid, and between the HT temperature control point and the heat exchange fluid.
The embodiment according to the invention has the advantage that heat transferred to the heat exchange fluid can be made available to other temperature control points to be preheated. This may particularly be of advantage during a starting operation in which different zones have not yet been brought to the operating temperature.
In such an arrangement, each of the temperature control points can be formed as a separate primary circuit in principle, which is designed such that the heat flow can be dissipated to a secondary circuit via a heat exchanger. Preferably, such a secondary circuit is part of the central heat exchange system or is a further closed circuit in heat-exchanging relationship with the central heat exchange system. However, each of the temperature control points can as well be formed as a circuit that is flown through directly by a process agent, in particular the heat exchange fluid in the central heat exchange system, such that the heat flow is transferred together with the process agent circulating in the circuit, so that the heat flow is coupled to the flowing carrier mass of the process agent flow. Process agent refers to arbitrary fluids supplied to printing machines for operation thereof and/or circulating in the printing machines, in particular dampening water, cleaning agents, transmission oil and/or other fluids used for cooling specific components.
A design of the temperature control points, in which the two designs are combined, is also conceivable. A separate primary circuit as described above can be formed as an open primary circuit, in which the fluid at the temperature control point is used up in part, e.g. dampening water, or as a closed primary circuit, in which the inflow is equal to the outflow.
A dampening agent is used on printing machines, among others, for wetting the non-printing points of a printing plate in order to thus prevent trapping in these zones. Excess dampening water is collected and fed back into the circuit. Since dampening water often comprises volatile components, dampening water is usually cooled to low temperatures before being applied to the printing plates. Thereby, an evaporation of the volatile components is clearly reduced, though not completely prevented. This zone of a printing machine will usually be an NT zone in conformity with the invention, the temperature of which is controlled by the NT temperature control point. Since at this point, as just described, dampening water is only partly fed back into the circuit, as far as it has not been used up, this circuit is referred to as “open”. In addition, such an NT zone can also be temperature controlled by a preferred closed circuit, e.g. by a circuit in the interior of a printing cylinder. This preferred closed circuit would also be part of the NT temperature control point and the temperature thereof could as well be controlled with dampening water, but also with another process agent in the described case.
The heat transfer between the temperature control points and the central heat exchange system is preferably conducted without converting the energy form thermal energy into electrical energy or other energy forms. This applies also in the case of interposition of a refrigerating machine. In the refrigerating machine, the refrigerant absorbs heat by evaporation, the refrigerant is heated further when being compressed and releases the entire excess heat to the environment or the heat exchange fluid via a heat exchanger. In doing so, the mechanical energy in the compressor only generates heat “in addition”. Even with the use of a refrigerating machine is the already absorbed heat not converted, but is still present in the refrigerant and is dissipated by same to the heat exchange system as part of the exhaust heat.
In the present invention, the temperature levels are referred to as “high”, “medium”, and “low” only for the purpose of indicating a not insignificant difference between the operating temperatures. Apart from that, the terms do not have any quantitative significance. However, the difference between the NT zone and the MT zone is preferably at least 5° C. The difference between the MT zone and the HT zone is preferably at least 10° C. Particularly preferably, the operating temperature of the NT zone is between 5° C. and 15° C., particularly preferably in the range from approx. 10° C. Such an operating temperature is possible on printing machines particularly in the area of a dampening unit. With respect to the MT zone, the operating temperature is preferably between 15° C. and 30° C., particularly preferably in the range from approx. 20° C. and 25° C. Such a range of possible operating temperatures is applied on printing machines e.g. in the printing zone of a printing machine, in particular to the distributor rollers and/or the ductor rollers. The operating temperature of the HT zone is preferably between 45° C. and 75° C., and particularly preferably in the range between approx. 50° C. and 65° C. Such a temperature range is e.g. applied in UV dryers (operating temperature approx. 60° C.), sheet guide plates (operating temperature approx. 50° C.), and in the cooling of blast air or compressed air (operating temperature between 60° C. and 90° C.).
Further, an embodiment of the arrangement is preferred in which the arrangement further comprises a cold generator arranged and designed such that the NT temperature control point can be temperature controlled by means of the cold generator. Such a cold generator preferably comprises a refrigerating machine, more preferably a compressor-operated refrigerating machine with condenser.
A further advantageous embodiment relates to an arrangement in which both the NT temperature control point and the MT temperature control point can be temperature controlled by means of the cold generator.
Preferably, such an arrangement has a design in which the cold generator is arranged such that the exhaust heat flow generated by the cold generator can directly be transferred to the heat exchange fluid in the central heat exchange system.
Further, such an embodiment is preferred in which the arrangement further comprises a cooling device. A cooling device is preferably formed by a heat exchanger or comprises a heat exchanger via which the arising heat flow can be dissipated to the environment. Such a heat exchanger may be a free cooler. Free cooler temperature control apparatus means an apparatus utilising approx. the temperature of the ambient air for cooling the heat exchange fluid. The heat exchange fluid can e.g. directly flow through the cooling device or be connected therewith via an additional heat exchanger. A free cooler can preferably be an adiabatic free cooler provided with a liquid application device, in particular a spraying device, wherein liquid can be applied to areas of the adiabatic free cooler, so that cooling performance can be increased and/or cooling to lower temperatures is possible by evaporation of the liquid. Here, it is preferred that the liquid can be applied in a controlled manner dependent on parameters, e.g. if a greater cooling performance is required and/or if a reduction of the cooling temperature is required, e.g. if the outside temperature is too high. A cooling device may also comprise a liquid/liquid heat exchanger that is e.g. cooled with ground water; etc.
A further advantageous embodiment relates to such an arrangement in which both the HT temperature control point and the MT temperature control point can be temperature controlled by means of the cooling device.
Further, a design of an arrangement is preferred in which the cold generator, in the operating state of the printing machine, is in a permanently cooling relationship with the NT temperature control point.
Moreover, such an arrangement preferably has a design in which the cooling device, in the operating state of the printing machine, is in a permanently cooling relationship with the HT temperature control point.
Further, an embodiment of the arrangement is preferred in which the cold generator and the cooling device, in the operating state of the printing machine, can be brought into a cooling relationship with the MT temperature control point dependent on an ambient temperature around the cooling device. Here, the cooling relationship is preferably shown such that an exhaust heat flow of the MT temperature control point can be dissipated to the cold generator and/or the cooling device.
A further advantageous embodiment relates to such an arrangement in which a heat flow can be transferred from the MT temperature control point and/or the HT temperature control point to the cooling device via the heat exchange fluid in the central heat exchange system.
Further, an embodiment of the arrangement is preferred in which the arrangement further comprises a cold producer arranged and designed such that the MT temperature control point can be temperature controlled by means of the cold generator. The cold producer preferably comprises a refrigerating machine, more preferably a compressor-operated refrigerating machine with an evaporator and a condenser, and more preferably an air-cooled refrigerating machine.
A further advantageous embodiment relates to an arrangement in which both the MT temperature control point and the NT temperature control point can be temperature controlled by means of the cold producer.
Preferably, such an arrangement has a design in which the cold producer is arranged such that the exhaust heat flow generated by the cold producer can be directly transferred to the heat exchange fluid in the central heat exchange system.
Further, such an arrangement is preferred in which the cold generator and the cold producer are operated with refrigerants having different evaporating temperatures and/or different condensation temperatures.
A further advantageous embodiment relates to an arrangement in which the central heat exchange system comprises a heat exchange circuit with a central inlet and a central outlet, wherein several, parallel partial branches extend between the central inlet and the central outlet, wherein a partial inlet of a partial branch passes to one of the temperature control points, wherein a partial outlet of a partial branch, coming from the temperature control point, leads to the central outlet such that a central heat exchange fluid flow in the central inlet can be divided into different heat exchange fluid partial flows, wherein the different heat exchange fluid partial flows can be fed to different temperature control points, and wherein the different heat exchange fluid partial flows, coming from the different temperature control points, can be brought together again in the central outlet to form the central heat exchange fluid flow. Here, the central heat exchange fluid flow has the same temperature in the central inlet and in the partial inlets. The temperatures in the partial outlets differ depending on the operating temperature of the operating points. The partial fluid flows in the partial outlets are mixed together in the respective sections of the central outlet, so that these sections each have a different temperature until finally, in the flow direction behind the last partial outlet, all heat exchange fluid partial flows unite in the last section of the central outlet.
Further, a design of an arrangement is preferred in which at least one of the partial branches can be cut off via a valve. The valve can preferably be controlled dependent on the operating temperature at the operating point and the temperature of the inflowing central heat exchange fluid flow and/or the inflowing heat exchange fluid partial flow, wherein the valve is preferably closed if the temperature of the inflowing central heat exchange fluid flow and/or the inflowing heat exchange fluid partial flow is higher than the (actual or intended) operating temperature at the operating point.
Further, such an arrangement preferably has a design in which at least part of the heat flow transferred to the heat exchange fluid can be dissipated to a heat consumer. Such a heat consumer may be a heater for an ink distributor temperature control device and/or a preheating device for preheating thermo-air, which is e.g. used for drying the printed printing substance. Arbitrary other heat consumers are conceivable as well.
Further, an embodiment of the arrangement is preferred in which the part of the heat flow that can be dissipated can be removed from the partial outlet of a partial branch. Preferably, the part of the heat flow is removed in a partial branch having a temperature level suitable for the respective heat consumer. Preferably, the part of the heat flow is removed in a partial branch having a high temperature level, in particular in the partial outlet behind the HT temperature control point, since this point of the central heat exchange system usually has the highest temperature level. It is further preferred that the arrangement is designed such that different parts of the entire heat flow can be dissipated at different points of the central heat exchange system with different temperature levels for different heat consumers.
A further advantageous embodiment relates to such an arrangement in which the cooling device is directly flown through by the heat exchange fluid flow, wherein the heat exchange fluid flow can be led past the cooling device via a bypass line controllable with a bypass valve.
Further, an embodiment of the arrangement is preferred in which the cooling device comprises a separate cooling circuit in heat-exchanging relationship with the heat exchange fluid flow via a heat exchanger, wherein the separate cooling circuit can be controlled via a cooling circuit valve.
A further advantageous embodiment relates to an arrangement in which the bypass valve or the cooling circuit valve can be cut off in a controlled manner in the case that the intended operating temperature of one of the temperature control points connected to the central heat exchange system has not yet been reached and/or the temperature in the inlet of the central heat exchange system is higher than the actual temperature of the respective temperature control point.
Preferably, such an arrangement has a design in which the central heat exchange system is in a heat-exchanging relationship with individual temperature control point circuits, which are hydraulically separated from the central heat exchange system. Hydraulically separated as used herein means without flow connection, via which a heat flow could be transferred together with a fluid flow. In this preferred embodiment, the fluid circuits remain separate and can therefore be operated e.g. with different temperature control fluids. Accordingly, merely the respective heat flows are transferred to the central heat exchange system by the hydraulically separate temperature control point circuits. Here, a central heat exchanger, which is in a heat-exchanging relationship with several or all of the temperature control point circuits, can preferably be provided in the central heat exchange system, wherein the heat flows of the respective temperature control point circuits are transferred to a heat exchange fluid provided in the central heat exchanger. Accordingly, in this preferred embodiment, the different temperature levels in the temperature control point circuits are standardised to a temperature of the heat exchange fluid in the central heat exchanger.
Further, such an arrangement is preferred in which the heat-exchanging relationship between one of the mutually separate temperature control point circuits and the central heat exchange system is designed in a separable manner such that no heat flow can be transferred from the temperature control point circuit to the central heat exchange system any more. A separation of one of the temperature control point circuits can preferably be established via a respective bypass line controllable by a valve. The valve is preferably designed in a controllable manner dependent on the operating temperature at the respective operating point and the temperature of the heat exchange fluid in the central heat exchange system, wherein the valve is preferably closed if the temperature of the heat exchange fluid is higher than the (actual or intended) operating temperature at the operating point.
A further advantageous embodiment relates to such an arrangement in which at least part of the heat flow transferred to the heat exchange fluid can be dissipated to a heat consumer. Such a heat consumer may be a heater for an ink distributor temperature control device and/or a preheating device e.g. usable for preheating thermo-air, which can e.g. be used for drying the printed printing substance.
Further, a design of an arrangement is preferred in which at least part of an exhaust heat flow arising at one of the operating points can be dissipated to a heat consumer, wherein the arrangement is designed such that this exhaust heat flow can be dissipated from a point of the respective temperature control point circuit which is arranged downstream of the operating point before the central heat exchange system. For this purpose, a heat consumer heat exchanger is preferably provided in the respective temperature control point circuit, which is flown through by the respective temperature control fluid in the respective temperature control point circuit, the fluid flowing in the direction of the central heat exchange system. The fluid transfers the part of the heat flow to the respective feed circuit of the heat consumer. Advantageously, heat can be taken from that temperature control point circuit that has a temperature level suitable for the respective temperature control point circuit. Preferably, the part of the heat flow is removed in a temperature control point circuit having a high temperature level, in particular the temperature control point circuit of the HT temperature control point, since it usually has the highest temperature level. Further preferably, the arrangement is designed such that different parts of the entire heat flow can be dissipated from different temperature control point circuits having different temperature levels for different heat consumers.
Further, such an arrangement preferably has a design in which the cooling device is directly flown through by the heat exchange fluid flow, wherein the heat exchange fluid flow can be led past the cooling device via a bypass line controllable with a bypass valve.
Further, an embodiment of the arrangement is preferred in which the cooling device comprises a separate cooling circuit in heat-exchanging relationship with the heat exchange fluid flow via a heat exchanger, wherein the separate cooling circuit can be controlled via a cooling circuit valve.
A further advantageous embodiment relates to an arrangement in which the bypass valve or the cooling circuit valve can be cut off in a controlled manner in the case that the intended operating temperature of one of the temperature control points connected to the central heat exchange system has not yet been reached and/or the temperature in the inlet of the central heat exchange system is higher than the actual temperature of the respective temperature control point.
Further, an embodiment of the arrangement is preferred in which the arrangement further comprises a buffer storage in which heat can be temporarily stored in a heat storage substance.
A further advantageous embodiment relates to an arrangement in which the heat storage substance comprises a larger amount of heat exchange fluid.
Preferably, such an arrangement has a design in which two central heat exchange systems are provided, wherein one of the two central heat exchange systems is provided to supply heat consumers with heat, as is described in claims 17 to 21 and 24 to 29, and wherein the other of the two central heat exchange systems comprises the cooling device.
The following aspects of the invention relate to other embodiments of the same invention. Therefore, substantially the same terminology is used. The above explanations regarding individual terms, advantages and embodiments therefore apply to the following aspects accordingly.
A second aspect of the invention relates to an arrangement on a printing machine, comprising at least one low-temperature temperature control point (NT temperature control point), at least one medium-temperature temperature control point (MT temperature control point), and at least one high-temperature temperature control point (HT temperature control point), which are arranged in a low-temperature zone (NT zone), a medium-temperature zone (MT zone), and at least one high-temperature zone (HT zone) of a printing machine and are designed such that the NT zone can be controlled to a low temperature by means of the NT temperature control point, the MT zone to a medium temperature by means of the MT temperature control point, and the HT zone to a high temperature by means of the HT temperature control point, the low temperature being lower than the medium temperature and the medium temperature being lower than the high temperature,
wherein the arrangement further comprises a low-temperature temperature control device (NT temperature control device) and a high-temperature temperature control device (HT temperature control device),
wherein the MT temperature control point can be temperature controlled both via the NT temperature control device and the HT temperature control device.
This design has the advantage that e.g. the NT temperature control device can e.g. be adapted for a low temperature, which is used anyway on the printing machine depending on the design of e.g. an NT temperature control point, whereas the HT temperature control device can be adapted such that it is able to utilize the ambient temperature for temperature control in an energy-saving manner. Therefore, depending on the ambient temperature and the desired operating temperature, an inventive embodiment can advantageously be designed such that the desired operating temperature can be obtained by a combination of both temperature control devices, which is optimised with respect to the desired performance and optimum energy utilization.
Here, an essential component of the HT temperature control device preferably is a free cooler. In the present invention, the temperature levels are referred to as “high”, “medium”, and “low” only for the purpose of indicating a not insignificant difference between the operating temperatures. Apart from that, the terms do not have any quantitative significance. However, the difference between the NT zone and the MT zone is preferably at least 5° C. The difference between the MT zone and the HT zone is preferably at least 10° C. Particularly preferably, the operating temperature of the NT zone is between 5° C. and 15° C., particularly preferably in the range from approx. 10° C. Such an operating temperature is possible on printing machines particularly in the zone of a dampening unit. With respect to the MT zone, the operating temperature is preferably between 15° C. and 30° C., particularly preferably in the range from approx. 20° C. and 25° C. Such a range of possible operating temperatures is applied on printing machines e.g. in the printing zone of a printing machine, in particular to the distributor rollers and/or the ductor rollers. The operating temperature of the HT zone is preferably between 45° C. and 75° C., and particularly preferably in the range between approx. 50° C. and 65° C. Such a temperature range is e.g. applied in UV dryers (operating temperature approx. 60° C.), sheet guide plates (operating temperature approx. 50° C.), and in the cooling of blast air or compressed air (operating temperature between 60° C. and 90° C.).
Further, an embodiment of the arrangement is preferred in which the NT temperature control device and the HT temperature control device are connected with the MT temperature control point such that the MT temperature control point can be temperature controlled by the NT temperature control device and the HT temperature control device at the same time.
A further advantageous embodiment relates to an arrangement in which the NT temperature control device and the HT temperature control device are connected with the MT temperature control point such that the MT temperature control point can be temperature controlled either by the NT temperature control device or the HT temperature control device at a specific time dependent on specific parameters. Such parameters may be the actual and/or intended temperature of the MT operating point and/or the temperature control range to be achieved by the HT temperature control device. This temperature control range can in turn depend on the temperature of a heat exchange fluid. It is further conceivable that if the HT temperature control device is a free cooler, as it is described above, such a parameter is the ambient temperature around the free cooler.
Preferably, such an arrangement has a design in which the NT temperature control device comprises a cold generator. Such a cold generator preferably comprises a refrigerating machine, more preferably a compressor-operated refrigerating machine with condenser.
Further, an embodiment of the arrangement is preferred in which the arrangement further comprises a central heat exchange system designed such that the NT temperature control point, the MT temperature control point, and the HT temperature control point can be temperature controlled via the central heat exchange system, wherein a pipe system of the central heat exchange system can be flown through by a heat exchange fluid, and wherein the heat exchange system is connected with the NT temperature control point, the MT temperature control point, and the HT temperature control point such that heat flows can be transferred both between the NT temperature control point and the heat exchange fluid, and between the MT temperature control point and the heat exchange fluid, and between the HT temperature control point and the heat exchange fluid. The heat transfer between the temperature control points and the central heat exchange system is preferably conducted without converting the energy form thermal energy into electrical energy or other energy forms. This applies also in the case of interposition of a refrigerating machine. In the refrigerating machine, the refrigerant absorbs heat by evaporation, the refrigerant is heated further when being compressed (mechanical energy) and releases the entire excess heat to the environment or the heat exchange fluid via a heat exchanger. In doing so, the mechanical energy in the compressor only generates heat “in addition”. Even with the use of a refrigerating machine is the already absorbed heat not converted, but is still present in the refrigerant and is dissipated by same to the heat exchange system as part of the exhaust heat.
A further advantageous embodiment relates to an arrangement in which the cold generator is arranged such that the exhaust heat flow generated by the cold generator can directly be transferred to the heat exchange fluid in the central heat exchange system.
Preferably, such an arrangement has a design in which the HT temperature control device comprises a cooling device. A cooling device is preferably formed by a heat exchanger or comprises a heat exchanger via which the arising heat flow can be dissipated to the environment. Such a heat exchanger may be a free cooler. Free cooler temperature control apparatus means an apparatus utilising approx. the temperature of the ambient air for cooling the heat exchange fluid. The heat exchange fluid may be a process agent. Process agent refers to arbitrary fluids supplied to printing machines for operation thereof and/or circulating in the printing machines, in particular dampening water, cleaning agents, transmission oil and/or other fluids used for cooling specific components. A free cooler can preferably be designed as an adiabatic free cooler provided with a liquid application device, in particular a spraying device, wherein liquid can be applied to areas of the adiabatic free cooler, so that cooling performance can be increased and/or cooling to lower temperatures is possible by evaporation of the liquid. Here, it is preferred that the liquid can be applied in a controlled manner dependent on parameters, e.g. if a greater cooling performance is required and/or if a reduction of the cooling temperature is required, e.g. if the outside temperature is too high. A cooling device may also comprise a liquid/liquid heat exchanger that is e.g. cooled with ground water; etc.
Further, a design of an arrangement is preferred in which the cold generator, in the operating state of the printing machine, is in a permanently cooling relationship with the NT temperature control point.
A further advantageous embodiment relates to an arrangement in which the cooling device, in the operating state of the printing machine, is in a permanently cooling relationship with the HT temperature control point.
Further, an embodiment of the arrangement is preferred in which the arrangement further comprises a central heat exchange system designed such that the NT temperature control point, the MT temperature control point, and the HT temperature control point can be temperature controlled via the central heat exchange system, wherein a pipe system of the central heat exchange system can be flown through by a heat exchange fluid, and wherein the heat exchange system is connected with the NT temperature control point, the MT temperature control point, and the HT temperature control point such that heat flows can be transferred both between the NT temperature control point and the heat exchange fluid, and between the MT temperature control point and the heat exchange fluid, and between the HT temperature control point and the heat exchange fluid.
A further advantageous embodiment relates to such an arrangement in which the arrangement is designed such that a heat flow can be transferred from the MT temperature control point and/or the HT temperature control point to the cooling device via the heat exchange fluid in the central heat exchange system.
Preferably, such an arrangement has a design in which the arrangement further comprises a cold producer arranged and designed such that the MT temperature control point can be temperature controlled by means of the cold generator. The cold producer preferably comprises a refrigerating machine, more preferably a compressor-operated refrigerating machine with an evaporator and a condenser, and more preferably an air-cooled refrigerating machine.
Further, such an arrangement is preferred in which both the MT temperature control point and the NT temperature control point can be temperature controlled by means of the cold producer.
A further advantageous embodiment relates to such an arrangement in which the cold producer is arranged such that the exhaust heat flow generated by the cold producer can be directly transferred to the heat exchange fluid in the central heat exchange system.
Further, a design of an arrangement is preferred in which the cold generator and the cold producer are operated with refrigerants having different evaporating temperatures and/or different condensation temperatures.
Further, such an arrangement preferably has a design in which the central heat exchange system comprises a heat exchange circuit with a central inlet and a central outlet, wherein several, parallel partial branches extend between the central inlet and the central outlet, wherein a partial inlet of a partial branch passes to one of the temperature control points, wherein a partial outlet of a partial branch, coming from the temperature control point, leads to the central outlet such that a central heat exchange fluid flow in the central inlet can be divided into different heat exchange fluid partial flows, wherein the different heat exchange fluid partial flows can be fed to different temperature control points, and wherein the different heat exchange fluid partial flows, coming from the different temperature control points, can be brought together again in the central outlet to form the central heat exchange fluid flow. Here, the central heat exchange fluid flow has the same temperature in the central inlet and in the partial inlets. The temperatures in the partial outlets differ depending on the operating temperature of the operating points. The partial fluid flows in the partial outlets are mixed together in the respective sections of the central outlet, so that these sections each have a different temperature until finally, in the flow direction behind the last partial outlet, all heat exchange fluid partial flows unite in the last section of the central outlet.
Further, a design of the arrangement is preferred in which at least one of the partial branches can be cut off via a valve. The valve can preferably be controlled dependent on the operating temperature at the operating point and the temperature of the inflowing central heat exchange fluid flow and/or the inflowing heat exchange fluid partial flow, wherein the valve is preferably closed if the temperature of the inflowing central heat exchange fluid flow and/or the inflowing heat exchange fluid partial flow is higher than the (actual or intended) operating temperature at the operating point.
A further advantageous embodiment relates to such an arrangement in which at least part of the heat flow transferred to the heat exchange fluid can be dissipated to a heat consumer. Such a heat consumer may be a heater for an ink distributor temperature control device and/or a preheating device for preheating thermo-air, which is e.g. used for drying the printed printing substance. Arbitrary other heat consumers are conceivable as well.
A further advantageous embodiment relates to such an arrangement in which the part of the heat flow that can be dissipated can be removed from the partial outlet of a partial branch. Preferably, the part of the heat flow is removed in a partial branch having a temperature level suitable for the respective heat consumer. Preferably, the part of the heat flow is removed in a partial branch having a high temperature level, in particular in the partial outlet behind the HT temperature control point, since this point of the central heat exchange system usually has the highest temperature level. It is further preferred that the arrangement is designed such that different parts of the entire heat flow can be dissipated at different points of the central heat exchange system with different temperature levels for different heat consumers.
Further, an embodiment of the arrangement is preferred in which the cooling device is directly flown through by the heat exchange fluid flow, and wherein the heat exchange fluid flow can be led past the cooling device via a bypass line controllable with a bypass valve.
A further advantageous embodiment relates to an arrangement in which the cooling device comprises a separate cooling circuit in heat-exchanging relationship with the heat exchange fluid flow via a heat exchanger, wherein the separate cooling circuit can be controlled via a cooling circuit valve.
Preferably, such an arrangement has a design in which the bypass valve or the cooling circuit valve can be cut off in a controlled manner in the case that the intended operating temperature of one of the temperature control points connected to the central heat exchange system has not yet been reached and/or the temperature in the inlet of the central heat exchange system is higher than the actual temperature of the respective temperature control point.
Further, such an arrangement is preferred in which the central heat exchange system is in a heat-exchanging relationship with individual temperature control point circuits, which are hydraulically separated from the central heat exchange system. Hydraulically separated as used herein means without flow connection, via which a heat flow could be transferred together with a fluid flow. In this preferred embodiment, the fluid circuits remain separate and can therefore be operated e.g. with different temperature control fluids. Accordingly, merely the respective heat flows are transferred to the central heat exchange system by the hydraulically separate temperature control point circuits. Here, a central heat exchanger, which is in a heat-exchanging relationship with several or all of the temperature control point circuits, can preferably be provided in the central heat exchange system, wherein the heat flows of the respective temperature control point circuits are transferred to a heat exchange fluid provided in the central heat exchanger. Accordingly, in this preferred embodiment, the different temperature levels in the temperature control point circuits are standardised to a temperature of the heat exchange fluid in the central heat exchanger.
A further advantageous embodiment relates to such an arrangement in which the heat-exchanging relationship between one of the mutually separate temperature control point circuits and the central heat exchange system is designed in a separable manner such that no heat flow can be transferred from the temperature control point circuit to the central heat exchange system any more. A separation of one of the temperature control point circuits can preferably be established via a respective bypass line controllable by a valve. The valve is preferably designed in a controllable manner dependent on the operating temperature at the respective operating point and the temperature of the heat exchange fluid in the central heat exchange system, wherein the valve is preferably closed if the temperature of the heat exchange fluid is higher than the (actual or intended) operating temperature at the operating point.
Further, a design of an arrangement is preferred in which at least part of the heat flow transferred to the heat exchange fluid can be dissipated to a heat consumer. Such a heat consumer may be a heater for an ink distributor temperature control device and/or a preheating device e.g. usable for preheating thermo-air, which can e.g. be used for drying the printed printing substance. Arbitrary other heat consumers are conceivable as well.
Further, such an arrangement preferably has a design in which at least part of an exhaust heat flow arising at one of the operating points can be dissipated to a heat consumer, wherein the arrangement is designed such that this exhaust heat flow can be dissipated from a point of the respective temperature control point circuit which is arranged downstream of the operating point before the central heat exchange system. For this purpose, a heat consumer heat exchanger is preferably provided in the respective temperature control point circuit, which is flown through by the respective temperature control fluid in the respective temperature control point circuit, the fluid flowing in the direction of the central heat exchange system. The fluid transfers the part of the heat flow to the respective feed circuit of the heat consumer. Advantageously, heat can be taken from that temperature control point circuit that has a temperature level suitable for the respective temperature control point circuit. Preferably, the part of the heat flow is removed in a temperature control point circuit having a high temperature level, in particular the temperature control point circuit of the HT temperature control point, since it usually has the highest temperature level. Further preferably, the arrangement is designed such that different parts of the entire heat flow can be dissipated from different temperature control point circuits having different temperature levels for different heat consumers.
Further, an embodiment of the arrangement is preferred in which the cooling device is directly flown through by the heat exchange fluid flow, wherein the heat exchange fluid flow can be led past the cooling device via a bypass line controllable with a bypass valve.
A further advantageous embodiment relates to such an arrangement in which the cooling device comprises a separate cooling circuit in heat-exchanging relationship with the heat exchange fluid flow via a heat exchanger, wherein the separate cooling circuit can be controlled via a cooling circuit valve.
Further, an embodiment of the arrangement is preferred in which the bypass valve or the cooling circuit valve can be cut off in a controlled manner in the case that the intended operating temperature of one of the temperature control points connected to the central heat exchange system has not yet been reached and/or the temperature in the inlet of the central heat exchange system is higher than the actual temperature of the respective temperature control point.
A further advantageous embodiment relates to an arrangement in which the arrangement further comprises a buffer storage in which heat can be temporarily stored in a heat storage substance.
Preferably, such an arrangement has a design in which the heat storage substance comprises a larger amount of heat exchange fluid.
Further, such an arrangement is preferred in which two central heat exchange systems are provided, wherein one of the two central heat exchange systems is provided to supply heat consumers with heat, as is described above, and wherein the other of the two central heat exchange systems comprises the cooling device.
The first and third aspects of the invention relate to other embodiments of the same invention described with respect to the second aspect of the invention. Therefore, substantially the same terminology is used. The above explanations regarding individual terms, advantages and embodiments therefore apply to the other aspects of the invention accordingly.
A third aspect of the invention relates to an arrangement on a printing machine, comprising at least one low-temperature temperature control point (NT temperature control point) and at least one medium-temperature temperature control point (MT temperature control point), which are arranged in a low-temperature zone (NT zone) and a medium-temperature zone (MT zone) of a printing machine and are designed such that the NT zone can be controlled to a low temperature by means of the NT temperature control point and the MT zone to a medium temperature by means of the MT temperature control point, the low temperature being lower than the medium temperature,
wherein the NT temperature control point and the MT temperature control point are connected with a heat consumer system via a central heat exchange system, which can be flown through by a heat exchange fluid, such that the exhaust heat flows generated at the NT temperature control point and the MT temperature control point during controlling the temperature can at least partly be transferred to the heat consumer system.
“At least partly transferred” as used herein means preferably that at least one partial exhaust heat flow can be transferred from each of the two temperature control points to the heat consumer system. In the present invention, the temperature levels are referred to as “low” and “medium” only for the purpose of indicating a not insignificant difference between the operating temperatures. Apart from that, the terms do not have any quantitative significance. Therefore, the terms described with respect to this aspect of the invention—as far as only two temperature levels are described—can also be replaced by the terms “medium” and “high” or “low” and “high” described with respect to the other aspects of the invention.
Further, an embodiment of the arrangement is preferred in which the arrangement further comprises a high-temperature temperature control point (HT temperature control point), which is arranged in a high-temperature zone (HT zone) of the printing machine and is designed such that the HT zone can be controlled to a high temperature by means of the HT temperature control point, the high temperature being higher than the low temperature and higher than the medium temperature. The difference between the NT zone and the MT zone is preferably at least 5° C. The difference between the MT zone and the HT zone is preferably at least 10° C. Particularly preferably, the operating temperature of the NT zone is between 5° C. and 15° C., particularly preferably in the range from approx. 10° C. Such an operating temperature is possible on printing machines particularly in the zone of a dampening unit. With respect to the MT zone, the operating temperature is preferably between 15° C. and 30° C., particularly preferably in the range from approx. 20° C. and 25° C. Such a range of possible operating temperatures is applied on printing machines e.g. in the printing zone of a printing machine, in particular to the distributor rollers and/or the ductor rollers. The operating temperature of the HT zone is preferably between 45° C. and 75° C., and particularly preferably in the range between approx. 50° C. and 65° C. Such a temperature range is e.g. applied in UV dryers (operating temperature approx. 60° C.), sheet guide plates (operating temperature approx. 50° C.), and in the cooling of blast air or compressed air (operating temperature between 60° C. and 90° C.).
A further advantageous embodiment relates to an arrangement in which the arrangement further comprises a central heat reservoir, wherein heat consumers are connected to the central heat reservoir, to which the heat can be dissipated from the central heat reservoir.
Preferably, such an arrangement has a design in which the arrangement is designed such that heat-dissipating fluid flows, coming from the temperature control points, are fed to the central heat exchange system via temperature control point lines, wherein the fluid flows unite in the central heat exchange system. Thereby, preferably a large heat buffer can be created in the heat reservoir, from which buffer the heat consumer system can be fed.
Further, such an arrangement is preferred in which at least part of an exhaust heat flow arising at one of the operating points can be dissipated to a heat consumer, wherein the arrangement is designed such that this exhaust heat flow or partial exhaust heat flow can be dissipated from a point of the respective temperature control point line which is arranged downstream of the operating point before the central heat reservoir.
A further advantageous embodiment relates to such an arrangement in which the arrangement is designed such that for at least one of the heat-dissipating fluid flows, coming from the temperature control points, a temperature control point circuit is provided which is formed hydraulically separated from the central heat reservoir, so that merely a heat flow is transferred to the central heat reservoir from the heat-dissipating fluid flow. Only heat flow is transferred to the central heat reservoir—but not a fluid flow. The temperature control point circuit is hydraulically separated from the heat reservoir. Thereby, preferably different fluids can be used. Individual temperature control point circuits can be hydraulically connected with each other and be hydraulically separated from other temperature control point circuits.
Further, a design of an arrangement is preferred in which at least part of an exhaust heat flow arising at one of the operating points can be dissipated to a heat consumer without being transferred to the central heat reservoir, wherein the arrangement is designed such that this exhaust heat flow or partial exhaust heat flow can be dissipated from a point of the respective temperature control point circuit which is arranged downstream of the operating point before the central heat reservoir. For this purpose, a heat consumer heat exchanger is preferably provided in the respective temperature control point circuit, which is flown through by the respective temperature control fluid in the respective temperature control point circuit, the fluid flowing in the direction of the central heat exchange system. The fluid transfers the part of the heat flow to the respective feed circuit of the heat consumer. Advantageously, heat can be taken from that temperature control point circuit that has a temperature level suitable for the respective temperature control point circuit. Preferably, the part of the heat flow is removed in a temperature control point circuit having a high temperature level, in particular the temperature control point circuit of the HT temperature control point, since it usually has the highest temperature level. Further preferably, the arrangement is designed such that different parts of the entire heat flow can be dissipated from different temperature control point circuits having different temperature levels for different heat consumers.
Further, such an arrangement preferably has a design in which the heat exchange system is connected with at least two temperature control points such that a heat flow can be transferred from one of the at least two temperature control points to the other of the at least two temperature control points via the heat exchange fluid. The heat transfer between the temperature control points and the central heat exchange system is preferably conducted without converting the energy form thermal energy into electrical energy or other energy forms. This applies also in the case of interposition of a refrigerating machine. In the refrigerating machine, the refrigerant absorbs heat by evaporation, the refrigerant is heated further when being compressed (mechanical energy) and releases the entire excess heat to the environment or the heat exchange fluid via a heat exchanger. In doing so, the mechanical energy in the compressor only generates heat “in addition”. Even with the use of a refrigerating machine is the already absorbed heat not converted, but is still present in the refrigerant and is dissipated by same to the heat exchange system as part of the exhaust heat.
Further, an embodiment of the arrangement is preferred in which the arrangement further comprises a cold generator arranged and designed such that the NT temperature control point can be temperature controlled by means of the cold generator. Such a cold generator preferably comprises a refrigerating machine, more preferably a compressor-operated refrigerating machine with condenser.
Further, an embodiment of the arrangement is preferred in which both the NT temperature control point and the MT temperature control point can be temperature controlled by means of the cold generator.
A further advantageous embodiment relates to an arrangement in which the cold generator is arranged such that the exhaust heat flow generated by the cold generator can directly be transferred to the heat exchange fluid in the central heat exchange system. An exhaust heat flow as defined herein is to be understood such that the term comprises both the heat absorbed by the cold generator—i.e. the “generated” cold—and the dissipated heat produced by the cold generator.
Preferably, such an arrangement has a design in which the arrangement further comprises a cooling device. A cooling device is preferably formed by a heat exchanger or comprises a heat exchanger via which the arising heat flow can be dissipated to the environment. Such a heat exchanger may be a free cooler. Free cooler temperature control apparatus means an apparatus utilising approx. the temperature of the ambient air for cooling the heat exchange fluid. The heat exchange fluid may be a process agent. Process agent refers to arbitrary fluids supplied to printing machines for operation thereof and/or circulating in the printing machines, in particular dampening water, cleaning agents, transmission oil and/or other fluids used for cooling specific components. A free cooler can preferably be an adiabatic free cooler provided with a liquid application device, in particular a spraying device, wherein liquid can be applied to zones of the adiabatic free cooler, so that cooling performance can be increased and/or cooling to lower temperatures is possible by evaporation of the liquid. Here, it is preferred that the liquid can be applied in a controlled manner dependent on parameters, e.g. if a greater cooling performance is required and/or if a reduction of the cooling temperature is required, e.g. if the outside temperature is too high. A cooling device may also comprise a liquid/liquid heat exchanger that is e.g. cooled with ground water; etc.
Further, such an arrangement is preferred in which both the HT temperature control point and the MT temperature control point can be temperature controlled by means of the cooling device.
A further advantageous embodiment relates to such an arrangement in which the cold generator, in the operating state of the printing machine, is in a permanently cooling relationship with the NT temperature control point.
Moreover, a design of an arrangement is preferred in which the cooling device, in the operating state of the printing machine, is in a permanently cooling relationship with the HT temperature control point.
Further, such an arrangement preferably has a design in which the cold generator and the cooling device, in the operating state of the printing machine, can be brought into a cooling relationship with the MT temperature control point dependent on an ambient temperature around the cooling device. Here, the cooling relationship is preferably such that an exhaust heat flow of the MT temperature control point can be dissipated to the cold generator and/or the cooling device.
Further, an embodiment of the arrangement is preferred in which a heat flow can be transferred from the MT temperature control point and/or the HT temperature control point to the cooling device via the heat exchange fluid in the central heat exchange system.
A further advantageous embodiment relates to such an arrangement in which the arrangement further comprises a cold producer arranged and designed such that the MT temperature control point can be temperature controlled by means of the cold generator. Such a cold producer preferably comprises a refrigerating machine, more preferably a compressor-operated refrigerating machine with an evaporator and a condenser, and more preferably an air-cooled refrigerating machine.
A further advantageous embodiment relates to an arrangement in which both the MT temperature control point and the NT temperature control point can be temperature controlled by means of the cold producer.
Further, an embodiment of the arrangement is preferred in which the cold producer is arranged such that the exhaust heat flow generated by the cold producer can be directly transferred to the heat exchange fluid in the central heat exchange system.
A further advantageous embodiment relates to an arrangement in which the cold generator and the cold producer are operated with refrigerants having different evaporating temperatures and/or different condensation temperatures.
Preferably, such an arrangement has a design in which the heat exchange system is formed as described in claims 15 to 28 with respect to the heat exchange system.
Further, such an arrangement is preferred in which the arrangement further comprises a buffer storage in which heat can be temporarily stored in a heat storage substance.
A further advantageous embodiment relates to such an arrangement in which the heat storage substance comprises a larger amount of heat exchange fluid and wherein the heat exchange fluid is hydraulically connected with the heat exchange fluid in the heat exchange system.
Further, such an arrangement preferably has a design in which
Moreover, a design of an arrangement is preferred in which two central heat exchange systems are provided, wherein one of the two central heat exchange systems is connected with at least one of the heat consumers, as has been explained with respect to the above-described heat exchange system, and wherein the other of the two central heat exchange systems comprises the cooling device. The central heat exchange system comprising the cooling device can have the same structural features, in particular with respect to the connection with the temperature control points, as the central heat exchange system connected with the heat consumer.
As pointed out above, the three different aspects of the invention are to be understood in a uniform manner, so that the explanations regarding the first aspect of the invention (e.g. to support claims 17 to 21 and 24 to 29) analogously apply to the here-described separation of consumer circuit and cooling circuit by two central heat exchange systems. Likewise, the explanations given here can be applied to the other two aspects of the invention.
In the following, individual particularly preferred embodiments of the invention will be described by way of example. The individual described embodiments partly have features that are not absolutely imperative for realising the present invention, but that are generally considered to be preferred. Thus, embodiments, which do not include all features of the embodiments described in the following, are to be considered to be disclosed as falling under the teaching of the invention as well. It is also conceivable to selectively combine features described with respect to different embodiments.
This applies in particular to the embodiments of
The figures show:
a a schematic illustration of a preferred embodiment of an inventive arrangement with fluid cooling, which is suitable for describing in particular the first two aspects of the invention by way of example,
b to 1d enlarged sections of
a gives an overview of the inventive arrangement on a printing machine 1 and thus a system with a cold generator preferably formed as a refrigerating machine, and a cooling device 3 formed as a free cooler in the present invention. As can be seen more clearly in
In
In such an arrangement, as is shown in
A separate primary circuit as described herein can be formed as an open primary circuit in which the fluid is partly used up at the temperature control point, such as in the case of dampening water, or as a closed primary circuit in which the inflow is equal to the outflow at any point of the primary circuit.
Further, it is conceivable in principle that each or some of the temperature control points have a circuit directly flown through by a process agent such that the heat flow is transferred together with the process agent circulating in the circuit, so that the heat flow is coupled to the flowing carrier mass of the process agent flow. This is exemplarily shown in
As shown, both designs of the temperature control points can be advantageously combined. However, this is not absolutely necessary, so that one of the designs can be sufficient.
The thus temperature controlled heat exchange fluid can be led to other temperature control points via the heat exchange circuit 62, which may be practical in the warm-up phase of a printing machine in order to provide the cold other temperature control points with exhaust heat from another temperature control point. This can directly be done via cross connections 653, 654 between the partial branches of the temperature control points, as is illustrated in
In order to redirect the fluid flow correspondingly, valves 661, 664 are provided. If the valve 661 is designed accordingly and depending on the valve position, a fluid flow, coming from the central inlet 63, could also flow to the heat exchanger 681 of the NT temperature control point via a section of the cross connection 653 in order to cool the NT temperature control point. This may be practical in particular at low outside temperatures, such as in winter, if the heat exchange circuit 62 is used for cooling and, as shown, is in heat-exchanging connection with a cooling device 3. As required, the heat exchange circuit 62 can be connected with or cut off from the cooling device 3 via the bypass line 67 and the bypass valve 671 for this purpose.
Depending on the minimum outside temperature at the operating times, it may be preferred that the NT temperature control point is permanently cooled by the cold generator 2, i.e. always when exhaust heat is to be dissipated.
Since an NT temperature control point can usually be cooled to approx. 10° C., the cold generator 2 will preferably be designed so powerful that in addition at least part of the heat load of the MT cooling points can be dissipated, e.g. if with rising ambient temperature the free cooler is not sufficient any more.
The intermediate circuit supplies the MT temperature control point with the cooling side of the cold generator 2 via the cross connections 653, 654. The exhaust heat of the cold generator 2 can in turn preferably be dissipated to the heat exchange fluid in the heat exchange circuit 62.
A corresponding circulation in the circuits, which can change course depending on the valve position, is preferably generated by circulation pumps, which can be switched on as required.
Preferably, in the individual temperature control points, 3-2 directional valves and associated bypasses can provide for a constant temperature at the temperature control points, as this is exemplarily illustrated with respect to the MT temperature control point 52 above the heat exchanger 682.
The HT temperature control point(s) to be cooled to a temperature of usually above 50° C. are cooled preferably all year round by a cooling device 3 formed as a free cooler. Here, it is further advantageous if the other temperature control points, which regularly have operating temperatures that cannot be cooled by a free cooler or only in an uneconomical manner all year round, can be cut off in the heat exchange circuit 62 such that a heat exchange fluid that is too warm does not reach them.
In such a temperature control system, it is therefore particularly beneficial that all three temperature control points participate from the cooling performance and/or from the exhaust heat among one another and/or can be temperature controlled via an ambient temperature without or with only little external energy.
For example, a printing operation cannot be started until all circuits have reached the desired temperature. For the NT circuit, this is usually achieved by cooling, and for the MT or optionally the HT circuit normally by heating.
In the inventive circuitry it is now possible to utilise the arising exhaust heat for the temperature control of the respective circuit higher with respect to the temperature level via the internal recooling circuit.
Here, a design can be preferred in which the bypass valve 671 is a 3-2 directional valve (46) and only transfers that much thermal energy to the free cooler that no additional thermal energy has to be generated by means of electric heaters for the temperature control of the MT and HT circuits.
As soon as the working temperature of the printing machine 1 is reached and the printing process itself generates exhaust heat by e.g. fulling and/or drive motors, it is desirable for energetic reasons that the free cooler dissipates as much thermal energy to the environment as possible.
The savings potential is, among others, dependent on the ambient conditions and the actually needed temperature levels specially of the MT cooling points, since the working temperature of e.g. 20-25° C. can be generated only to a limited extent in full or in part by the free cooler.
Here, two separate refrigerating machines can optimise the system further, since the refrigerating machines can be operated at different evaporating temperatures.
Since a refrigerating machine usually works energetically more efficiently the higher the evaporating temperature is (which is possible due to higher water temperatures), it has turned out that there are energetic advantages if fluid temperatures of e.g. 10° C. and 20-25° C. are generated with separate refrigerating machines.
Here as well, a heat exchanger 684 is additionally—exemplarily—provided only in a hydraulically separate circuit of the MT temperature control point to exclusively or partially dissipate heat via the free cooler. This heat exchanger 684 can be switched off by an illustrated 2 directional valve as required.
As can be seen in
By means of a valve, which is illustrated in
Only the shortened central inlets 63 and central outlets 64 in
In the illustration of
In addition to the so-far described temperature control points, a blast air cooling device 7 is provided which is also connected to the heat exchanger 91.
As is shown, further exhaust heat sources, such as the water-cooled refrigerating machine, an UV dryer, sheet guide plates, and the blast or compressed air supply 7 are further connected to the heat exchanger 91, since here comparatively high temperature levels are generated for a reasonable use. Other exhaust heat sources are conceivable as well.
The heat accommodated in the heat reservoir 92 is dissipated to the heat consumer 93 as required.
In the illustrated heat recovery, the different temperature levels are combined to one mixed temperature, which is higher than the lowest temperature level but lower than the highest temperature level.
In the heat recovery shown in
Further heat consumers and/or a cooling device can preferably be connected to the lines leading away from the heat reservoir 92.
In the embodiment shown in
| Number | Date | Country | Kind |
|---|---|---|---|
| 102007053080.5 | Nov 2007 | DE | national |
| Filing Document | Filing Date | Country | Kind | 371c Date |
|---|---|---|---|---|
| PCT/EP2008/009420 | 11/7/2008 | WO | 00 | 5/6/2010 |
