KR20010077966A - Device for supplying dampening water in offset printing machines - Google Patents

Abstract

PURPOSE: A dampening water supplying device for an offset printer is provided to control the temperature of the dampening water not by any cooler attached to a dampening water supply unit additionally but by a water supply pan or a dampening water storage tank directly attached with a thermo-element. CONSTITUTION: A dampening water supplying device for an offset printer includes a water supply pan(20) for receiving dampening water and a thermo-element(40) mounted to the water supply pan for cooling or heating the dampening water thermo-electrically, wherein the thermo-element is mounted to a bottom surface and/or a side surface of the water supply pan, and the thermo-element is provided with a heat sink and a blowing fan for helping the heat exchange operation of the heat sink.

Description

Device for supplying dampening water in offset printing machines

The present invention relates to an apparatus for supplying a condensation water of an offset printing machine, and more particularly, to an apparatus for condensation supply of an offset printing machine which controls a temperature of a condensation water used for offset printing and supplies it to a printing press. .

In general, the principle of offset printing is to print by using the repulsive force of water and ink.The PS plate is specially treated so that the non-fire line has hydrophilicity and the fire line has a lipophilic characteristic, so that ink is selectively applied only to the fire line. Then, it is transferred to the blanket, and then transferred from the blanket to paper again to print.

At this time, water that imparts hydrophilicity to the non-radiation portion to prevent ink is called condensate, which can be classified into acidic, neutral, and alkaline according to pH. In modern commercial printing, most of the acid is used, and alkalinity is mainly used for newspaper printing.

As such, the supply of condensate is essential for offset printing, and the condensate is typically composed of a high concentration of fountain solution, water, and isopropyl alcohol (IPA).

Each of these ratios depends on the damping method. In the case of the continuous watering method, the condensate is about 1 to 5% of high concentration of water, 80 to 95% of water, and 5 to 20% of isopropyl alcohol. Consists of

It is common to use condensate on a printing machine after cooling it to about 10 ~ 15 ℃, but it is 5 ℃ ~ 20 ℃ according to various variables such as the type of press, ambient temperature, type of ink, type of print, speed of press, and component of condensate. The operator adjusts the temperature in between.

1 shows a condensate supply device of a conventional offset printing press. As shown, in a typical offset printing press, the printing plate 1 is installed while being wound on the plate 2, and the plate 2 has several ink rollers 5 for completely mixing the ink and constantly supplying the mixed ink. Are connected.

The ink transferred to the plate cylinder 2 by the ink roller 5 is transferred to the blanket cylinder 3, and an impression cylinder 4 and a blanket cylinder for rolling the paper are pressed. 3) It is printed on the printing paper 7 passing through. The condensate is supplied from the feed pan 20 to the plate 2 through a plurality of rollers such as the condenser roller 6.

If you continue printing, condensate will be contaminated by stakes, ink debris, etc. and the pH will change. In addition, heat is generated by friction between the rollers, and the temperature of the condensate rises. Therefore, in order to obtain long-term clean print quality, the temperature of condensate must be lowered.

On the other hand, in the case of the conventional offset printing machine, condensate circulation method for circulating condensate between condensate in condensate and condensate storage tank 10 in order to lower the temperature of condensate was used. In addition, in order to cool the condensate, the condenser storage tank 10 uses a cooler 12 separately using a refrigerant such as CFC.

Therefore, according to the conventional cooling method of the condensate supply device, since a refrigerant such as CFC, which causes ozone layer destruction, is used in the separately attached cooler 12, there is a problem that environmental pollution occurs.

In addition, when trying to use a refrigerant with less influence of environmental pollution to avoid such a problem, there was a problem that the refrigerant purchase cost increases. In addition, since the cooler 12 requires equipment such as a compressor and a heat exchanger, there is a problem that the volume of the condensate supply device becomes large and noise and vibration occur in the compressor.

On the other hand, the condensate supply device of some printers may be provided with only a water supply fan without the condensate circulation device and the condensate storage tank. In this case, since there is no separate cooler and circulation device, ice was put into the feed pan as a temporary measure to lower the temperature of the condensate. However, in such a case, it is difficult to maintain the condensate at an appropriate temperature by compensating for the temperature change of the condensate at an appropriate time.

In addition, the condensate supply device of the small offset printing press is composed of only a feed fan without condensate circulation device and condensate storage tank. That is, because of the limited space and the amount of condensate required, it was not possible to separately install the condensate circulator and the cooler using the CFC refrigerant to lower the condensate temperature. Therefore, when the ambient temperature is high, it is difficult to obtain stable print quality because the condensate is not maintained at an appropriate temperature.

Therefore, the technical problem to be achieved by the present invention, that is, the object of the present invention is to solve the above problems of the condensate supply apparatus of the conventional offset printing machine, the structure is simpler than the prior art, more precise temperature control is It is possible to provide a condensate feeder of a possible offset printing press.

1 is a view for explaining a conventional condensate supply device.

2 is a view showing a condensate supply device according to a first embodiment of the present invention.

3 is a view showing a condensate supply device according to a second embodiment of the present invention.

Figure 4 is an enlarged detail view of the water supply pan and its surroundings in the condensed water supply device of FIGS.

5 illustrates another embodiment for cooling a thermoelectric element.

6 is a circuit diagram of a thermoelectric device applied to preferred embodiments of the present invention.

Explanation of symbols on the main parts of the drawings

10: condensate storage tank 11: pump

20: water supply fan 21: inlet hole

22: outflow hole 23: insulation

30: circulation passage 40: thermoelectric element

41: heat sink 41a, 72a: fin

42: ventilation fan 43: P-type semiconductor

44: N-type semiconductor 45: first contact

46, 47: second contact point 48: power supply

50: temperature sensor 60: control unit

71: first heat dissipation member 72: second heat dissipation member

73: heat pipe

The object of the present invention as described above, the offset according to the invention characterized in that it comprises a water supply pan (pan) for receiving condensate and a thermoelectric element installed in the water supply fan to thermoelectrically cool or heat the condensate It is achieved by providing a condensate feeder of a printing press.

Here, the thermoelectric element may be installed on the bottom and / or side of the water supply fan. In addition, in order to cool the thermoelectric element, a heat sink is preferably installed on one side of the thermoelectric element, and in order to assist in heat exchange of the heat sink, a fan is installed on one side of the heat sink. It is preferable.

In addition, as another embodiment for cooling the thermoelectric element, a first heat dissipation member is provided on one side of the thermoelectric element, and the first heat dissipation member is installed in a suitable place inside or outside of the printer through a heat pipe. It can also be connected to the heat radiating member.

Preferably, the first heat dissipation member is formed of a heat dissipation plate into which a heat pipe is inserted, and one side of the second heat dissipation member is further preferably provided with a blower fan for assisting heat exchange of the second heat dissipation member.

In addition, the object of the present invention as described above, in the condensate supply device of the offset printing machine having a condensate storage tank connected to the water supply fan for receiving condensate and the condensate circulation device to the water supply fan, the supply fan and / or the Condensate storage tank can also be achieved by providing a condensate supply device of the offset printing machine according to the invention, characterized in that the thermoelectric element for thermoelectrically cooling or heating the condensate is installed.

Here, the thermoelectric element may be installed on the bottom and / or side of the feed pan and / or the condensate storage tank. In addition, in order to cool the thermoelectric element, it is preferable that a heat sink is installed on one side of the thermoelectric element, and in order to assist the heat exchange action of the heat sink, a fan is preferably installed on one side of the heat sink.

In addition, as another embodiment for cooling the thermoelectric element, a first heat dissipation member is provided on one side of the thermoelectric element, and the first heat dissipation member is installed in a suitable place inside or outside of the printer through a heat pipe. It can also be connected to the heat radiating member.

It is preferable that the first heat dissipation member is formed of a heat dissipation plate into which a heat pipe is inserted, and one side of the second heat dissipation member is further preferably provided with a blow fan for assisting heat exchange of the second heat dissipation member.

Hereinafter, exemplary embodiments of the present invention will be described in detail with reference to the accompanying drawings. The same reference numerals are used for the same parts as the prior art, and detailed description thereof will be omitted.

2 shows a condensate supply apparatus according to a first embodiment of the present invention. As illustrated, the condensate supply device according to the first embodiment of the present invention includes a water supply fan 20, a thermoelectric element 40, and a controller 60.

The water supply fan 20 is installed at a predetermined position inside the printer to accommodate condensation, and the thermoelectric element 40 is installed in the water supply fan 20 to thermoelectrically cool or heat the condensation, and the control unit 60 is a thermoelectric element. The operation of 20 is controlled.

The thermoelectric element 40 is installed on the bottom surface of the water supply fan 20. The control unit 60 may be a switch that is turned on / off according to a user's need, and may simply control the thermoelectric element 40 on / off within a preset temperature range, such as a bimetal.

In addition, the controller 60 may include a sensor for sensing the temperature of the condensate in the water supply fan 20. In this case, the controller 60 may automatically operate the thermoelectric element 20 according to a temperature preset by a user, including a microcomputer.

The controller 60 may be implemented in a wide variety of ways, and the implementation manner of the controller 60 is not limited to the above examples. The condensate supply device as shown in FIG. 2 can be applied to a small offset printing press having a small amount of condensate.

3 shows a condensate supply device according to a second embodiment of the present invention. As shown, the condensate supply apparatus according to the second embodiment of the present invention, the condensate storage tank 10, the water supply fan 20, the thermoelectric element 40 and the control unit 60.

The condensed matter storage tank 10 is separately installed outside the printing press, and the water supply fan 20 is installed at a predetermined position inside the printing press. The condensation storage tank 10 and the water supply fan 20 are connected by a circulation passage 30.

The pump 11 is installed at the connection portion between the condensation storage tank 10 and the circulation passage 30. The water supply fan 20 is provided with a thermoelectric element 40 for cooling or heating condensate. The thermoelectric element 40 is installed on the bottom surface of the water supply fan 20.

As described above in the first embodiment of the present invention, the controller 60 may be implemented in a wide variety of ways, and the implementation manner of the controller 60 is not limited to the examples. The condensate supply device as shown in FIG. 3 can be applied to a medium-large offset printing press with a large amount of condensate.

4 is an enlarged detailed view of the water supply fan 20 and its surroundings in the condensate supply device of FIGS. 2 and 3. As shown, the thermoelectric element 40 is installed on the bottom of the water supply fan 20, and the temperature sensor 50 is installed in the water supply fan 20 to detect the temperature of the condensate.

The bottom surface of the thermoelectric element 40 is provided with a heat sink 41 and a blower fan 42 to facilitate the heat exchange between the thermoelectric element 40 and the ambient atmosphere. Here, the water supply fan 20 is preferably made of a material having good thermal conductivity for smooth heat exchange with the thermoelectric element 40, and is preferably insulated other than the junction surface with the thermoelectric element 40.

In the heat sink 41, many fins 41a are formed in order to raise heat dissipation efficiency. In addition, the inlet hole 21 and the outlet hole 22 are formed in the water supply fan 20, respectively (the simple water supply fan without an inlet hole and an outlet hole may be used). The formation position of the inflow hole 21 and the outflow hole 22 is not limited to the position shown.

Condensate supplied by the pump 11 from the storage tank 10 is introduced into the feed fan 20 through the inlet hole (21). When the water level of the water supply fan 20 is above a certain level, the condensate overflowed is returned to the storage tank 10 through the outlet hole 22.

A heat insulator 23 may be attached to the outer surface of the water supply fan 20 to prevent heat exchange with the ambient atmosphere other than the junction surface with the thermoelectric element 40. As the heat insulating material 23, cork, foamed styrol, and the like, which are generally used, may be used.

By attaching the heat insulator 23 to the water supply fan 20 in this way, the cooling efficiency of the thermoelectric element 40 can be improved, and dew can be prevented from forming on the outer surface of the water supply fan 20 as the condensate is cooled.

On the other hand, the cooling method of the thermoelectric element 40 as shown in Figure 4 occupies a considerable volume due to the presence of the fin 41a and the blowing fan 42. This phenomenon worsens as the amount of heat generated by the thermoelectric element 40 increases. Therefore, the case that the implementation of the printing machine is difficult when there is a spatial constraint inside the printing machine regardless of the type of the printing press.

Another embodiment for cooling the thermoelectric element 40 that can be applied in this case is shown in FIG. 5. Referring to FIG. 5, a finless first heat dissipation member 71 is disposed below the thermoelectric element 40.

As the first heat dissipation member 71, a heat pipe imbedded heat sink in which a heat pipe 73 called "heat superconducting pipe", which is commercially available and commercially available, is inserted. The first heat dissipation member 71 is connected to the second heat dissipation member 72 installed at a suitable place inside or outside the printer through the heat pipe 73.

The second heat dissipation member 72 includes a plurality of fins 72a. One side of the second heat dissipation member 72 is provided with a blower 42 for assisting the heat exchange action of the second heat dissipation member 72. That is, it is spatially advantageous because the fin 72a and the blower 42 which occupy a relatively large volume do not necessarily need to be installed around the water supply fan 20.

6 is a circuit diagram of a thermoelectric element 40 applied to embodiments of the present invention. The thermoelectric element 40 uses the Peltier effect and, as illustrated, is configured to include a P-type semiconductor 43 and an N-type semiconductor 44.

One side of the P-type semiconductor 43 and the N-type semiconductor 44 is connected to the first contact 45, and the other side thereof is connected to two second contacts 46 and 47 that are insulated from each other. 6 shows a circuit when the thermoelectric element 40 cools the condensate, wherein the anode of the power supply 48 is connected to the second contact 47 on the N-type semiconductor 44 side, and the cathode is P. FIG. It is connected to the second contact 46 on the side of the type semiconductor 43.

Meanwhile, the first contact 45 is in contact with the water supply fan 20, and the second contact 46 and 47 are installed in contact with the heat sinks 41 and 71. In this state, when a DC voltage is applied, electrons absorbing thermal energy from the surroundings are moved into the N-type semiconductor 44 at the first contact point 45 and endothermic occurs, and at the second contacts 46 and 47, Heat is generated by the release of thermal energy. Therefore, cooling of condensate in the water supply fan 20 is made.

When the condensate is to be heated by the thermoelectric element 40, the polarity of the power source 48 is switched by a generally known switching circuit, and the anode of the power source 48 is connected to the second contact 46 on the P-type semiconductor 43 side. ), The cathode is connected to the second contact point 47 on the N-type semiconductor 44 side, respectively, and endotherm occurs at the second contact points 46 and 47, and heat generation occurs at the first contact point 45 so that the water supply fan Condensate in 20 is heated.

Based on the result detected by the temperature sensor 50, it is determined whether the condensate is required to be cooled or heated, and the polarity of the power supply 48 is switched, and current is supplied to the thermoelectric element 40 until the condensate reaches a desired temperature. By shedding the precise temperature control of condensate is possible.

In the above embodiment, the thermoelectric element 40 is illustrated and described in the case where the thermoelectric element 40 is installed on the bottom surface of the water supply fan 20. It is also possible to install.

In addition, the thermoelectric element 40 may be installed on the bottom and / or side of the condensation storage tank 10 to adjust the temperature of the condensation. In addition, the thermoelectric element 40 may be installed in both the feed fan 20 and the condensate storage tank 10.

Therefore, according to the condensation material supply apparatus of the offset printing machine according to the present invention as described above, the thermoelectric element 40 is supplied to the water supply fan 20 without using the cooler 12 separately attached to the condensation material supply device as in the related art. Directly attached to the condensation storage tank 10 to adjust the temperature of condensation.

Therefore, the structure of the condensate supply device is simplified, and the noise and vibration problems caused by the compressor or the like in the cooler 12 are improved. In addition, since the refrigerant does not need to be used, it does not cause environmental pollution, and the condensate can be easily cooled or heated by reversing the polarity of the power source 48 of the thermoelectric element 40, thereby enabling precise temperature control.

In the above, certain preferred embodiments of the present invention have been illustrated and described. However, the present invention is not limited to the above-described embodiments, and various modifications can be made by those skilled in the art without departing from the gist of the present invention as claimed in the claims. will be.

Claims (12)

And a thermoelectric element installed in the feed pan for thermoelectrically cooling or heating the condensate. The apparatus of claim 1, wherein the thermoelectric element is installed at a bottom and / or side of the water supply fan. The apparatus of claim 1, wherein one side of the thermoelectric element is provided with a heat sink and a fan for assisting heat exchange between the heat sink. The heat dissipation member of claim 1, wherein a first heat dissipation member is installed at one side of the thermoelectric element, and the first heat dissipation member is connected to a second heat dissipation member installed at a suitable place inside or outside the printer through a heat pipe. Condensate feeder of offset printing press. 5. The condenser supply apparatus of claim 4, wherein the first heat dissipation member is a heat dissipation plate into which a heat pipe is inserted. 5. The condenser supply apparatus of claim 4, wherein a blower is provided on one side of the second heat dissipation member to assist a heat exchange action of the second heat dissipation member. In the condensate supply device of the offset printing machine having a condensate storage tank connected to the condensate through a condensate circulation device to the condensate, Condensate supply device of the offset printing machine, characterized in that the water supply fan and / or the condensate storage tank is provided with a thermoelectric element for thermoelectrically cooling or heating the condensate. 8. The condenser supply apparatus of claim 7, wherein the thermoelectric element is installed at a bottom and / or side of the feed pan and / or the condensate storage tank. The apparatus of claim 7, wherein one side of the thermoelectric element is provided with a heat sink and a fan for assisting heat exchange between the heat sink. The heat dissipation member according to claim 7, wherein a first heat dissipation member is installed at one side of the thermoelectric element, and the first heat dissipation member is connected to a second heat dissipation member installed at a suitable place inside or outside the printer through a heat pipe. Condensate feeder for offset presses. 11. The condenser supply apparatus of claim 10, wherein the first heat dissipation member is a heat dissipation plate into which a heat pipe is inserted. 12. The condensate supply device of claim 10, wherein a blower is provided on one side of the second heat dissipation member to assist a heat exchange action of the second heat dissipation member.