JP2009270457A - Liquid circulation system - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a liquid circulation system capable of reducing an influence of pulsation (vibration) caused by the vibration of a diaphragm, in a liquid circulation system using a diaphragm pump. <P>SOLUTION: This liquid circulation system is provided for circulating liquid to a circulating flow passage by discharging the liquid to a discharge port from a pump room by sucking the liquid in the pump room from a suction port by a volumetric change in the pump room. The liquid circulation system is provided so that a pulsation reducing chamber having a pulsation reducing diaphragm composed of an elastic material is arranged at least between the suction port and the circulating flow passage of a diaphragm pump and between the discharge port and the circulating flow passage, and one of front/reverse liquid chambers of the pulsation reducing diaphragm is made to communicate with one of the suction port and the discharge port, and the other is made to communicate with the other of the suction port and the discharge port. <P>COPYRIGHT: (C)2010,JPO&INPIT

Description

  The present invention relates to a liquid circulation system using a diaphragm pump (variable volume pump).

  An example of a pump that obtains a pump action by a vibrating diaphragm is a piezoelectric pump. The piezoelectric pump forms a pump chamber by a flat circular piezoelectric vibrator (diaphragm) and a housing. A suction port and a discharge port leading to the pump chamber are formed in the housing, respectively. Between the suction port and the pump chamber, suction is allowed to flow from the suction port to the pump chamber, but not to the opposite direction. A side check valve is provided, and a discharge side check valve is provided between the pump chamber and the discharge port that allows fluid flow from the pump chamber to the discharge side reservoir and does not allow fluid flow in the opposite direction. Yes. When the piezoelectric vibrator vibrates, in the process of increasing the volume of the pump chamber, the inflow side check valve opens and the discharge side check valve closes, and fluid flows into the pump chamber from the suction port. In the smaller stroke, the discharge-side check valve opens and the suction-side check valve closes, and fluid is discharged from the pump chamber to the discharge port, thereby obtaining a pump action.

The discharge port and the suction port are connected by a circulation channel. In a water cooling system that cools a heat source (CPU, GPU, chipset, etc.) of a notebook PC under development by the present applicant, a heat receiving part that takes heat away from the heat source is received in this circulation channel, and the temperature is increased by receiving heat. And a heat dissipating part for dissipating the heat of the liquid.
Japanese Utility Model Publication No. 2-112985 Japanese Utility Model Publication No. 6-1780 JP 11-247742 A JP 2001-227472 A JP 2002-202061 A JP 2006-200524 JP 2006-316785 A

  In such a liquid circulation system, pulsation in which the pressure in the suction port and the discharge port fluctuates due to vibration of the vibration diaphragm is unavoidable. The pulsation simultaneously causes a loud driving sound (noise) and deterioration of the durability of the piezoelectric vibrator.

  Conventional diaphragm pump pulsation prevention structure generally has one chamber on the front and back of a pulsation reducing diaphragm made of an elastic material provided separately from the vibration diaphragm communicated with an intake port or a discharge port, and air is sealed in the other chamber. Yes. The idea is to absorb the pressure fluctuation of the suction port or the discharge port by the volume change of the sealed air chamber. According to the analysis of the present inventor, the volume change of the air chamber is about 10 to 20% of the volume change. It is difficult to effectively reduce the pulsation without increasing the volume of the air chamber. In addition, there is a problem that air is reduced by long-term use and the pulsation reducing effect is lowered.

  It is an object of the present invention to obtain a liquid circulation system using a diaphragm pump that can effectively reduce pulsation with a simple structure.

  In the conventional apparatus, the front and back sides of the pulsation reducing diaphragm are liquid chambers and the other side is a sealed air chamber, whereas both front and back sides are liquid chambers, and one of the front and back liquid chambers is a suction port or The present invention has been completed by paying attention to the fact that the effect of reducing the pulsation is high if it is communicated with the discharge port, the other is communicated with the discharge port or the suction port, and the liquid is introduced into the front and back of the pulsation reduction diaphragm.

  That is, the present invention allows a fluid flow from a suction port provided in a suction chamber connected to the pump chamber of a variable volume formed by a vibrating diaphragm to the pump chamber to the pump chamber and does not allow a fluid flow in the opposite direction. A diaphragm pump having at least one pair of a suction side check valve and a discharge side check valve that allows fluid flow from the pump chamber to the discharge port provided in the discharge port communicating with the pump chamber and does not allow fluid flow in the opposite direction; And a circulation flow path from the discharge port of the diaphragm pump to the suction port; the liquid is sucked from the suction port into the pump chamber by the volume change of the pump chamber, and the liquid is discharged from the pump chamber to the discharge port. In a liquid circulation system that circulates liquid in a passage, between a suction port of a diaphragm pump and a circulation flow path, and between a discharge port and a circulation flow path At least one of the pulsation reduction chambers is formed, and the pulsation reduction chamber is provided with a pulsation reduction diaphragm made of an elastic material that forms liquid chambers on the front and back sides. And the discharge port, and the other is connected to the other of the suction port and the discharge port.

  In one aspect of the present invention, the pulsation reduction chamber having the pulsation reduction diaphragm is formed both between the suction port and the circulation flow path of the diaphragm pump and between the discharge port and the circulation flow path, and the pair of pulsation reduction diaphragms. One of the front and back liquid chambers can be communicated with one of the suction port and the discharge port, and the other can be communicated with the other of the suction port and the discharge port.

  In another aspect, a pulsation reducing chamber of the same specification is formed between the suction port of the diaphragm pump and the circulation channel and between the discharge port and the circulation channel, and one and the other of the pair of pulsation reduction chambers are formed. Further, a pulsation reducing diaphragm and a perforated diaphragm are provided, and one of the liquid chambers on the front and back sides of the pulsation reducing diaphragm can be communicated with either the suction port or the discharge port by the flow path including the perforated diaphragm.

  Specifically, the liquid circulation system of the present invention is, for example, a liquid cooling system including a heat receiving part that takes heat from a heat generation source and a heat radiating part that dissipates heat of the liquid that has been heated and received heat in the circulation channel. Can be used.

  The present invention can be applied to a piezoelectric pump using a piezoelectric vibrator as at least a diaphragm.

  In the liquid circulation system of the present invention, a pulsation reducing chamber having a pulsation reducing diaphragm is formed between at least one of the suction port and the circulation flow path of the diaphragm pump and between the discharge port and the circulation flow path. Since one of the liquid chambers on the front and back sides is connected to one of the suction port and the discharge port, and the other is connected to the other of the suction port and the discharge port, the pressure fluctuation in the suction port (discharge port) is discharged. Absorbed by the liquid pressure in the port (suction port), pulsation (vibration, noise) can be reduced.

  FIG. 1 shows an embodiment in which the liquid circulation system of the present invention is applied to a liquid cooling system using a piezoelectric pump (diaphragm pump). This embodiment includes a heat receiving unit 10 having a first heat generation source 10A and a second heat generation source 10B, a heat radiation unit 20, and a piezoelectric pump 30.

  As shown in FIG. 4, the piezoelectric pump 30 includes a lower housing 30L and an upper housing 30U in order from the bottom. A piezoelectric vibrator (diaphragm) 35 is sandwiched and supported between the lower housing 30L and the upper housing 30U via an O-ring 33 and a presser ring 34, and the piezoelectric vibrator 35 and the lower housing 30L A pump chamber P is formed between the two. An atmospheric chamber A is formed between the piezoelectric vibrator 35 and the upper housing 30U.

The piezoelectric vibrator 35 includes a shim 35a formed of a conductive metal thin plate material, for example, a metal thin plate formed of stainless steel having a thickness of about 50 to 300 μm, 42 alloy, or the like, and at least one surface of the shim 35a (see FIG. The example is composed of a piezoelectric body 35b laminated on the upper surface only). The piezoelectric body 35b is made of, for example, PZT (Pb (Zr, Ti) O ₃ ) having a thickness of about 300 μm, and is polarized in the front and back directions. Is given. Such a piezoelectric vibrator is well known.

  The lower housing 30L is formed with a discharge port 31 and a suction port 32 (see FIG. 1) protruding outward, and a discharge chamber 31a and a suction chamber 32a communicating with the discharge port 31 and the suction port 32, respectively. The discharge chamber 31a and the suction chamber 32a are provided with check valves (umbrellas) 36 and 37 at the boundary between the discharge chamber 31a and the suction chamber 32a, respectively. The check valve 36 is a discharge-side check valve that allows a fluid flow from the pump chamber P to the discharge chamber 31a and does not allow a reverse fluid flow. The check valve 37 is a pump chamber P from the suction chamber 32a to the pump chamber P. This is a suction-side check valve that permits the fluid flow of the fluid and does not permit the reverse fluid flow.

  The check valves 36 and 37 have the same configuration, and are provided with umbrellas 36b and 37b made of an elastic material on perforated substrates 36a and 37a that are bonded and fixed to the flow path. Such a check valve (umbrella) itself is well known.

  In the piezoelectric pump 30 described above, when the piezoelectric vibrator 35 is elastically deformed (vibrated) in the forward and reverse directions, the suction-side check valve 37 is opened and the discharge-side check valve 36 is closed in a stroke in which the volume of the pump chamber P is increased. Therefore, the refrigerant flows into the pump chamber P from the suction port 32 (suction chamber 32a). On the other hand, in the stroke in which the volume of the pump chamber P is reduced, the discharge check valve 36 is opened and the suction check valve 37 is closed, so that the refrigerant flows out from the pump chamber P to the discharge port 31 (discharge chamber 31a). Therefore, the pump action can be obtained by elastically deforming (vibrating) the piezoelectric vibrator 35 continuously in the forward and reverse directions.

  The discharge port 31 and the suction port 32 of the piezoelectric pump 30 are connected to a series of circulation channels 40, and the heat receiving unit 10 and the heat dissipation unit 20 are installed on the circulation channel 40. A pulsation reducing block 50 is interposed between the discharge port 31 and the suction port 32 of the piezoelectric pump 30 and the circulation flow path 40. The piezoelectric pump 30 is a two-valve type in which a pair of discharge-side check valves and suction-side check valves are provided, but a four-valve type in which two pairs of discharge-side check valves and suction-side check valves are provided. Of course, a piezoelectric pump may be used.

  The pulsation reduction block 50 includes an upper housing 51 and a lower housing 52 as shown in FIG. A pair of circular recesses 511 having the same shape and an annular protrusion 512 concentric with the recess 511 are formed in the upper housing 51, and a pair of circular recesses 521 having the same shape corresponding to the circular recess 511 is formed in the lower housing 52. An annular groove 522 corresponding to the annular protrusion 512 is formed. A pulsation reducing chamber 53 is formed by the recess 511 and the recess 521.

  The peripheral bead portion 541 of the pulsation reducing diaphragm 54 made of an elastic material having a flat circular shape is fitted into the annular groove 522 of the lower housing 52. Then, the upper housing 51 is overlaid on the lower housing 52, the annular protrusion 512 is fitted into the annular groove 522, and the peripheral bead portion 541 is compressed, so that the liquid chamber 531 and 532 is formed. That is, liquid chambers 531 and 532 are formed in the pulsation reduction chamber 53 by the pulsation reduction diaphragm 54. The discharge port 31 and the suction port 32 open to the liquid chamber 532 below the pair of pulsation reduction chambers 53 in the drawing.

  In the upper housing 51 and the lower housing 52, a communication passage 55 is formed to communicate the liquid chamber 531 of one pulsation reduction chamber 53 with the liquid chamber 532 of the other pulsation reduction chamber 53. As a result, the liquid chambers on the front and back sides of the pulsation reduction diaphragm 54 of the pair of pulsation reduction chambers 53 communicate with the discharge port 31 and the suction port 32, respectively.

  FIG. 3 shows an example of a heat receiving structure of the heat sources 10A and 10B provided on the circulation flow path 40. The heat source 10A is, for example, a CPU of a PC, and the heat source 10B is the same chip set, and is placed on a heat spreader 102 (202) disposed in thermal contact with the liquid flow jacket 101 (201). The liquid flow jacket 101 (201) has a meandering flow path 101 a (201 a) that communicates with the circulation flow path 40. The liquid flow jacket 101 (201) has meandering channels 101a and 201a formed in the center plate of three laminated plates (brazing sheets). On the liquid flow jacket 101 (201), the heat spreader 102 (202), the heat source 10A (chip set 200), and the presser plate 103 (203) are arranged in an overlapping manner, and are coupled via the fastening means 104 (204). Has been.

  The heat dissipating unit 20 includes a radiator 21 that communicates with the circulation flow path 40 and a fan 22 that sends cooling air to the radiator 21.

  Accordingly, in the liquid cooling system (liquid circulation system) according to the present embodiment, the refrigerant discharged from the discharge port 31 of the piezoelectric pump 30 reaches the heat receiving unit 10 after passing through the pulsation reducing block 50. In the heat receiving part 10, heat is taken from the heat generating source 10 </ b> A through the meandering channel 101 a of the liquid flow jacket (heat receiving part) 101 immediately below the heat generating source 10 </ b> A. The refrigerant that has exited the liquid flow jacket 101 passes through the circulation flow path 40, passes through the meandering flow path 201a of the liquid flow jacket (heat receiving part) 201 immediately below the heat generation source 10B, and takes heat from the heat generation source 10B. The refrigerant that has exited the liquid flow jacket 201 reaches the radiator 21 of the heat radiating section 20 through the circulation flow path 40 and is cooled by receiving cooling air from the cooling fan 22 while flowing through the radiator 21. Thereafter, the pulsation reducing chamber pulsation reducing block 50 is entered through the circulation channel 40 and returned to the suction port 32 of the piezoelectric pump 30. Thereafter, the above circulation is repeated to cool the heat source 10A and the heat source 10B.

  As described above, this liquid circulation is caused by the pump action of the piezoelectric pump 30 that elastically deforms the piezoelectric vibrator 35 continuously in the forward and reverse directions, and this pump action causes the suction-side check valve 37 and the discharge-side check valve 36. Open and close alternately so that pressure fluctuations occur at the discharge port 31 and the suction port 32. The pressure fluctuation in the discharge port 31 and the suction port 32 is applied to the liquid chambers 531 and 532 of the pair of pulsation reduction chambers 53 of the pulsation reduction block 50, and the pulsation reduction diaphragm 54 is elastically deformed.

  What is characteristic in this embodiment is that the liquid chambers 531 and 532 on the front and back of the pulsation reducing diaphragm 54 are always in communication with the discharge port 31 and the suction port 32. For this reason, the pulsation reducing diaphragm 54 is elastically deformed according to the pressure difference between the discharge port 31 and the suction port 32, and can reduce pulsation (vibration, noise) appearing in the liquid pressure in the discharge port 31 and the suction port 32. it can. That is, in the pump discharge process, when the pressure of the liquid in the liquid chamber 532 (531) communicating with the discharge port 31 rises, the liquid chamber 531 (532) communicating with the suction port 32 on the opposite side of the pulsation reducing diaphragm 54. Since the internal pressure is relatively lowered, each of the pulsation reducing diaphragms 54 is elastically deformed toward the liquid chamber 531 (532) to absorb the pulsation. The same applies to the pump suction process.

  5 and 6 each show another embodiment of the present invention. The embodiment of FIG. 5 uses a perforated diaphragm 54H having a hole H as the diaphragm on the pulsation reduction chamber 53 side communicating with the suction port 32, and the embodiment of FIG. 6 has a pulsation reduction chamber 53 communicating with the discharge port 31. In this embodiment, a perforated diaphragm 54H having a hole H is used as the side diaphragm. The upper housing 51 is formed with a communication path 56 that allows the suction port 32 (discharge port 31) to communicate with the liquid chamber 531 above the pulsation reducing diaphragm 54 on the discharge port 31 (suction port 32) side through a perforated diaphragm 54H. Has been. Other configurations are the same as those in the embodiment of FIG. 2, and the same reference numerals are given to the same elements.

  In the embodiment of FIG. 5, since the pressure of the discharge port 31 and the suction port 32 is applied to the front and back of the pulsation reduction diaphragm 54 on the pulsation reduction chamber 53 side communicating with the discharge port 31, mainly in the pump discharge process. A pulsation reducing action is obtained. Further, in the embodiment of FIG. 6, the pressure of the discharge port 31 and the suction port 32 is exerted on the front and back of the pulsation reduction diaphragm 54 on the pulsation reduction chamber 53 side communicating with the suction port 32. A pulsation reducing action is obtained in the process. The pulsation reducing effect leads to a driving noise (vibration, noise) reduction effect at the same time.

  The embodiment of FIG. 5 and the embodiment of FIG. 6 can select the pulsation reducing action in the pump suction process and the pulsation reducing action in the discharge process by exchanging the pulsation reducing diaphragm 54 and the perforated diaphragm 54H. There are advantages. Of course, the perforated diaphragm does not function as a diaphragm, but substantially functions as a seal member. It is possible to form a similar flow path without using a perforated diaphragm. That is, in the aspect in which the pulsation reducing chamber 53 is provided in either the discharge port 31 or the suction port 32, the liquid chambers on the front and back sides of the pulsation reduction diaphragm 54 may be communicated with the discharge port 31 and the suction port 32. Further, the pulsation reducing effect can be further enhanced by reducing the size of the liquid chamber 53 on the perforated diaphragm 54H side and increasing the size of the liquid chamber 53 on the pulsation reducing diaphragm 54 side.

  In the above embodiment, the piezoelectric vibrator is exemplified as the diaphragm. However, the present invention can be widely applied to liquid pumps using other vibrating diaphragms.

  In the above embodiment, the housing and related elements are named “upper” and “lower” for convenience, but it is obvious that the housing and the elements are not limited to those in use.

It is a system connection top view which shows one Embodiment of the liquid circulation system by this invention. It is sectional drawing which follows the II-II line of FIG. It is sectional drawing which follows the III-III line of FIG. It is sectional drawing which follows the IV-IV line of FIG. FIG. 3 is a cross-sectional view corresponding to FIG. 2, showing another embodiment of the liquid circulation system according to the present invention. It is sectional drawing corresponding to FIG. 2 which shows another embodiment of the liquid circulation system by this invention.

Explanation of symbols

DESCRIPTION OF SYMBOLS 10 Heat receiving part 10A Heat generating source 10B Heat generating source 101 201 Liquid flow jacket (heat receiving part)
101a 201a Meandering channel 102 202 Heat spreader 103 203 Presser plate 104 204 Fastening means 20 Radiating part 21 Radiator 22 Cooling fan 30 Piezoelectric pump (diaphragm pump)
31 Discharge port 32 Suction port 35 Piezoelectric vibrator 36 Discharge side check valve 37 Suction side check valve 40 Circulation flow path 50 Pulsation reduction block 51 Upper housing 511 Recess 512 Recess 512 Lower housing 521 Recess 522 Annular groove 53 Pulsation reduction chamber 531 532 Liquid chamber 54 Pulsation reduction diaphragm 541 Peripheral bead portion 54H Perforated diaphragm 55 56 Communication path

Claims (5)

A variable-volume pump chamber formed by an oscillating diaphragm, a suction-side check valve that allows fluid flow from the suction port to the pump chamber provided in a suction port that communicates with the pump chamber and does not allow fluid flow in the opposite direction; And a diaphragm pump having at least a pair of discharge-side check valves that permit fluid flow from the pump chamber to the discharge port and that do not allow fluid flow in the opposite direction provided in the discharge port communicating with the pump chamber; and discharge of the diaphragm pump A circulation path from the port to the suction port;
With
In a liquid circulation system that sucks liquid from the suction port into the pump chamber by the volume change of the pump chamber, discharges the liquid from the pump chamber to the discharge port, and circulates the liquid in the circulation channel.
Forming a pulsation reducing chamber between at least one of the diaphragm pump suction port and the circulation flow path and between the discharge port and the circulation flow path;
This pulsation reducing chamber is provided with a pulsation reducing diaphragm made of an elastic material that forms liquid chambers on the front and back sides,
One of the liquid chambers on the front and back sides of the pulsation reducing diaphragm is connected to one of the suction port and the discharge port, and the other is connected to the other of the suction port and the discharge port. 2. The liquid circulation system according to claim 1, wherein the pulsation reducing chamber having the pulsation reducing diaphragm is formed between both the suction port and the circulation flow path of the diaphragm pump and between the discharge port and the circulation flow path. system. 2. The liquid circulation system according to claim 1, wherein pulsation reducing chambers having the same specifications are formed between the suction port and the circulation flow path of the diaphragm pump and between the discharge port and the circulation flow path, respectively. A pulsation reduction diaphragm and a perforated diaphragm are provided on one and the other of the reduction chambers, and one of the liquid chambers on the front and back of the pulsation reduction diaphragm is connected to either the suction port or the discharge port by the flow path including the perforated diaphragm. A fluid circulation system that communicates with either of these. 4. The liquid circulation system according to claim 1, wherein the circulation flow path includes a heat receiving portion that takes heat away from a heat generation source, and a heat radiating portion that dissipates heat of the liquid that has been heated and heated. Liquid circulation system included. 5. The liquid circulation system according to claim 1, wherein the diaphragm pump is a piezoelectric pump. 6.

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