Liquid-cooled heat sink

Abstract

To provide a liquid-cooled heat sink capable of improving cooling performance.SOLUTION: The liquid cooling heat sinks 100A, 100B, and 100C cool the heating element 200 by absorbing heat from the heating element 200 by the fluid flowing in the flow path 5. The liquid-cooled heat sink 100A, 100B, 100C comprises a pump 1 for pumping the fluid in the channel 5. The pump 1 includes an electromagnet 61, movable plates 62 and 63 that are attracted to the electromagnet 61 by a magnetic field M1 generated by energization of the electromagnet 61, leaf springs 64 and 65 that bias the movable plates 62 and 63 in a direction opposite to an attracting operation of the movable plates 62 and 63 to the electromagnet 61 in accordance with the attracting operation, pump chambers 7 and 8 provided on the flow path 5, and pistons 71, 72, 81, and 82 as volume changing members that operate to reduce and increase the volumes of the pump chambers 7 and 8 in accordance with the operation of the movable plates 62 and 63.SELECTED DRAWING: Figure 13

Description

[Technical Field]

[0001] The present disclosure relates to a liquid-cooled heat sink. [Background technology]

[0002] As a device for cooling a heat generating body, a configuration has been proposed in which heat is absorbed from the heat generating body by a fluid that moves or circulates within a flow path (for example, Patent Document 1). [Prior art documents] [Patent documents]

[0003] [Patent Document 1] Patent No. 4728694 Summary of the Invention [Problem to be solved by the invention]

[0004] Conventional cooling devices such as those described in Patent Document 1 require a pump to supply energy to move the fluid through the flow path. The performance of the pump affects the amount of fluid moved, which in turn affects the cooling performance. Conventional cooling devices have room for improvement in terms of cooling performance.

[0005] An object of the present invention is to provide a liquid-cooled heat sink that can improve cooling performance. [Means for solving the problem]

[0006] A liquid-cooled heat sink according to one aspect of an embodiment of the present invention is a liquid-cooled heat sink that cools a heat generating element by absorbing heat from the heat generating element with a fluid flowing through a flow path, and includes a pump that pumps out the fluid through the flow path, the pump including: an electromagnet; a movable plate that is attracted to the electromagnet by a magnetic field generated by energizing the electromagnet; a leaf spring to which the movable plate is attached and that urges the movable plate in a direction opposite to the attraction action of the movable plate to the electromagnet in response to the attraction action of the movable plate; a pump chamber provided on the flow path; and an operation to reduce the volume of the pump chamber in response to the attraction action of the movable plate, and The pump chamber has a volume change member that operates to increase the volume of the pump chamber in response to the movable plate moving away from the electromagnet due to the biasing force of the leaf spring when the electromagnet is switched off; an intake valve that is provided in the pump chamber upstream of the flow path and opens when the volume change member operates in a direction to increase the volume of the pump chamber, to draw the fluid from the upstream side of the flow path into the pump chamber; and a discharge valve that is provided in the pump chamber downstream of the flow path and opens when the volume change member operates in a direction to reduce the volume of the pump chamber, to discharge the fluid from the pump chamber to the downstream side of the flow path. [Effects of the Invention]

[0007] According to the present disclosure, it is possible to provide a liquid-cooled heat sink that can improve cooling performance. [Brief explanation of the drawings]

[0008] [Figure 1] FIG. 1 is a perspective view showing an example of the appearance of a pump according to an embodiment; [Figure 2] Schematic diagram showing the general configuration inside the housing of the pump shown in Figure 1 [Figure 3] FIG. 1 is a perspective view showing a schematic configuration of a resonant actuator; [Figure 4] An exploded perspective view of the resonant actuator shown in Figure 3. [Figure 5] 1 is a schematic diagram of a cross-sectional shape of a pump according to an embodiment taken along a symmetry axis CA; [Figure 6]10 is a schematic diagram of a cross-sectional shape of a fourth flow path of the pump according to the embodiment, taken along the axial direction; [Figure 7] Schematic diagram showing pump operation when coil is energized [Figure 8] 8 is a schematic diagram showing the first pump chamber and its surroundings in the state shown in FIG. 7; [Figure 9] Schematic diagram showing pump operation when the coil is de-energized [Figure 10] 10 is a schematic diagram showing the periphery of the first pump chamber in the state of FIG. [Figure 11] Schematic diagram of the magnetic field generated in an electromagnet using a flat core as a comparative example [Figure 12] Plan view of the internal structure of the pump housing from the Z positive side [Figure 13] FIG. 1 is a diagram showing a schematic configuration of a first example of a liquid-cooled heat sink according to an embodiment; [Figure 14] FIG. 10 is a diagram showing a schematic configuration of a second example of a liquid-cooled heat sink according to an embodiment; [Figure 15] FIG. 10 is a diagram showing a schematic configuration of a third example of a liquid-cooled heat sink according to an embodiment; DETAILED DESCRIPTION OF THE INVENTION

[0009] Hereinafter, embodiments will be described with reference to the accompanying drawings. To facilitate understanding of the description, the same components in the drawings will be denoted by the same reference numerals as much as possible, and duplicated descriptions will be omitted.

[0010] In the following description, the X, Y, and Z directions are perpendicular to one another. The X and Y directions are horizontal, and the Z direction is vertical. The X direction is the longitudinal direction of the housing 2 and the resonant actuator 6. The Y direction is the lateral direction of the housing 2 and the resonant actuator 6. For ease of explanation, the positive Z direction may also be referred to as the upper side, and the negative Z direction may also be referred to as the lower side.

[0011] [Basic pump configuration] The basic configuration of a pump 1 according to an embodiment will be described with reference to FIGS.

[0012] Fig. 1 is a perspective view showing an example of the appearance of a pump 1 according to an embodiment. The pump 1 illustrated in Fig. 1 is an element used as a drive source for liquid-cooled heat sinks 100A, 100B, and 100C according to this embodiment, which will be described later. As shown in Fig. 1, the pump 1 includes a housing 2, an intake port 3, and an exhaust port 4.

[0013] The housing 2 houses elements related to the pump function, such as a flow path 5 and a resonant actuator 6, which will be described later. In the example of Fig. 1, the housing 2 has a pair of rectangular main surfaces 21 and 22, and is formed in the shape of a rectangular parallelepiped, with the dimension between the main surfaces 21 and 22 being relatively thin compared to the sides of the main surfaces.

[0014] The pair of principal surfaces 21, 22 are formed to have the same shape and are arranged opposite each other in the Z direction. The pair of principal surfaces 21, 22 are arranged such that the long sides of the rectangle face each other in the Y direction and the short sides face each other in the X direction. That is, the pair of principal surfaces 21, 22 are formed so as to be line-symmetric in the Y direction with respect to an axis of symmetry CA (see FIG. 2) that passes through the center of the short sides in the Y direction and extends in the X direction, and are also formed so as to be line-symmetric in the X direction with respect to an axis of symmetry CB (see FIG. 2) that passes through the center of the long sides in the X direction and extends in the Y direction. FIG. 1 shows a center line CO of the pump 1 that passes through the intersection of these two axes of symmetry CA, CB (i.e., the center of the pair of principal surfaces 21, 22) and extends in the Z direction.

[0015] Four side surfaces 23 to 26 are provided between the pair of principal surfaces 21, 22, connecting the four sides of each principal surface. One pair of the four side surfaces 23, 24 is formed in the same rectangular shape and arranged opposite each other in the X direction, with the long sides of each side surface connected to the short sides of the pair of principal surfaces 21, 22. The other pair of the four side surfaces 25, 26 is formed in the same rectangular shape and arranged opposite each other in the Y direction, with the long sides of each side surface connected to the long sides of the pair of principal surfaces 21, 22.

[0016] Inlet port 3 draws fluid into housing 2. Outlet port 4 discharges fluid pressurized by the pump function inside housing 2. In the example of FIG. 1 , inlet port 3 is provided on the Y-negative side of side surface 23 of housing 2, and outlet port 4 is provided on the Y-positive side of side surface 24. Inlet port 3 and outlet port 4 are both connected in the X direction and are arranged so that the direction of fluid intake from inlet port 3 into housing 2 and the direction of fluid discharge from housing 2 to outlet port 4 are the same. In addition, inlet port 3 and outlet port 4 are arranged so that they are point-symmetrical when viewed from the Z direction with respect to the center line CO of pump 1.

[0017] FIG. 2 is a schematic diagram showing the general configuration inside the housing 2 of the pump 1 shown in FIG. 1. FIG. 2 is a plan view of the pump 1 as viewed from the positive Z direction. FIG. 2 schematically shows the internal structure of the housing 2, and the outer shape of the housing 2 (i.e., the four side surfaces 23-26) is shown by a two-dot chain line. FIG. 2 also shows by a dash-dot chain line an axis of symmetry CA that passes through the center in the Y direction of the main surfaces 21 and 22 of the housing 2 and extends in the X direction, and an axis of symmetry CB that passes through the center in the X direction and extends in the Y direction. In FIG. 2, the intersection of the axis of symmetry CA and the axis of symmetry CB is shown as a center line CO.

[0018] 2, the pump 1 is provided with a flow path 5 inside the housing 2, which connects the intake port 3 and the exhaust port 4. The flow path 5 has a first flow path 51, a second flow path 52, a third flow path 53, a fourth flow path 54, a fifth flow path 55, a sixth flow path 56, a seventh flow path 57, and an eighth flow path 58.

[0019] The first flow path 51 has its upstream end connected to the downstream end of the intake port 3 and is arranged to extend in the X-positive direction. The second flow path 52 and the third flow path 53 have their upstream ends both connected to the downstream end of the first flow path 51, branch off, and are arranged to extend in the X-negative direction and the X-positive direction, respectively. The fourth flow path 54 has its upstream end connected to the downstream end of the second flow path 52 and is arranged to extend in the Y-positive direction. The fifth flow path 55 has its upstream end connected to the downstream end of the third flow path 53 and is arranged to extend in the Y-positive direction. The sixth flow path 56 has its upstream end connected to the downstream end of the fourth flow path 54 and is arranged to extend in the X-positive direction, and the seventh flow path 57 has its upstream end connected to the downstream end of the fifth flow path 55 and is arranged to extend in the X-negative direction, and the sixth flow path 56 and the seventh flow path 57 are arranged to merge at their downstream ends. The eighth flow path 58 has its upstream end connected to the junction of the sixth flow path 56 and the seventh flow path 57, extends in the X positive direction, and is disposed so that its downstream end is connected to the upstream end of the outlet 4. Note that in Figure 2, the flow direction of the fluid flowing inside the intake port 3, the flow path 5, and the outlet 4 is shown by arrows.

[0020] 1, the inlet 3 and the outlet 4 are arranged so as to be point-symmetrical when viewed from the Z direction with respect to the center line CO of the pump 1. Therefore, it is preferable that the overall shape of the flow path 5 is also arranged so as to be point-symmetrical when viewed from the Z direction with respect to the center line CO of the pump 1. This makes it easier for the fluid to flow from the inlet 3 to the outlet 4 through the flow path 5.

[0021] Also, a resonant actuator 6 is installed inside the housing 2 as a drive source for the pump 1. The resonant actuator 6 has an electromagnet 61 and is a device that generates vibration motion by switching the electromagnet 61 between energized and de-energized states. The resonant actuator 6 also puts the movable part, which is a vibration element (a group of components including movable plates 62 and 63 and leaf springs 64 and 65, described below), into a resonant state by setting the frequency of the control signal that switches between energized and de-energized states (i.e., switching frequency) to the same frequency as or close to the resonant frequency of the movable part. As a result, the resonant actuator 6 can efficiently vibrate the movable part by utilizing the resonance of the movable part in addition to the attraction of the movable part by the electromagnet 61 when the electromagnet 61 is energized.

[0022] 2, the resonant actuator 6 is arranged so that the X direction is the longitudinal direction and the Y direction is the lateral direction, and is arranged at the center when viewed in the Z direction. Similar to the housing 2, the resonant actuator 6 is also formed so as to be line-symmetric in the Y direction with respect to the axis of symmetry CA, and so as to be line-symmetric in the X direction with respect to the axis of symmetry CB. The electromagnet 61 is arranged at the center of the resonant actuator 6.

[0023] Furthermore, the fourth flow path 54 of the flow path 5 is disposed adjacent to the electromagnet 61 on the negative X side, and is disposed so as to penetrate the resonant actuator 6 in the Y direction. Similarly, the fifth flow path 55 of the flow path 5 is disposed adjacent to the electromagnet 61 on the positive X side, and is disposed so as to penetrate the resonant actuator 6 in the Y direction.

[0024] Furthermore, a first pump chamber 7 and a second pump chamber 8 are provided in the fourth flow path 54 and the fifth flow path 55, respectively, at portions that overlap with the resonant actuator 6 as viewed in the Z direction. The first pump chamber 7 and the second pump chamber 8 are elements that pressurize and send fluid from the upstream side to the downstream side of the flow path 5 in response to the vibration motion of the resonant actuator 6. The fluid in the flow path 5 can flow from the intake port 3 to the exhaust port 4 by the operation of the first pump chamber 7 and the second pump chamber 8. In the example of FIG. 2, both the first pump chamber 7 and the second pump chamber 8 are arranged on the axis of symmetry CA of the housing 2 and the resonant actuator 6. As described above, in the example of FIG. 2, the shape of the flow path 5 is arranged to be point-symmetric as viewed in the Z direction with respect to the central axis CO that passes through the centers of the pair of main surfaces 21, 22 of the housing 2. As a result, the first pump chamber 7 and the second pump chamber 8 are each positioned at approximately the middle position on the flow path 5, so that the energy required to draw fluid into the first pump chamber 7 and the second pump chamber 8 and to discharge fluid from the first pump chamber 7 and the second pump chamber 8 can be made approximately the same.

[0025] The configuration of the resonant actuator 6 of the pump 1 according to this embodiment will be described with reference to Figures 3 and 4. Figure 3 is a perspective view showing a schematic configuration of the resonant actuator 6. Figure 4 is an exploded perspective view of the resonant actuator 6 shown in Figure 3. The perspective directions of Figures 3 and 4 are the same as those of Figure 1.

[0026] As shown in FIGS. 3 and 4, the resonant actuator 6 includes an electromagnet 61, a pair of movable plates 62 and 63, and a pair of leaf springs 64 and 65.

[0027] The electromagnet 61 is disposed at the center of the resonant actuator 6 in the Z direction. As shown in FIG. 4, the electromagnet 61 has a core 611 and a coil 612. The core 611 has a winding portion 611A and a pair of widened portions 611B. The winding portion 611A is located at the center of the core 611 in the X direction and is formed to extend in the X direction. The winding portion 611A has a rectangular cross section along the YZ plane, and has four outer circumferential surfaces with the Y positive side, Y negative side, Z positive side, and Z negative side as normal directions. A coil 612 is wound around the outer circumferential surface of the winding portion 611A. The pair of widened portions 611B are formed at both ends of the winding portion 611A in the X direction, protruding on both sides in the Z direction relative to the winding portion. Widened portion 611B also has a rectangular cross section along the YZ plane, and has four faces whose normal directions are the positive Y, negative Y, positive Z, and negative Z. That is, widened portion 611B has upper and lower end faces that protrude by the same amount from wound portion 611A along the Y direction.

[0028] When a current flows through the conductor that forms the coil 612, the electromagnet 61 generates a magnetic field that passes through the center of the coil 612. The magnetic field generated by the coil 612 is further strengthened by the core 611.

[0029] The pair of movable plates 62, 63 are plate-like members made of a magnetic material, and include a first movable plate 62 and a second movable plate 63. The first movable plate 62 is disposed on the positive Z side of the electromagnet 61, and the second movable plate 63 is disposed on the negative Z side of the electromagnet 61. The first movable plate 62 and the second movable plate 63 are formed in the same shape and are disposed opposite each other in the Z direction.

[0030] Since the first movable plate 62 and the second movable plate 63 are made of magnetic material, they are attracted to the electromagnet 61 by the magnetic field generated by energizing the electromagnet 61. Furthermore, when the electromagnet 61 changes from an energized state to a de-energized state, the first movable plate 62 and the second movable plate 63 move in the direction opposite to the attracting action due to the biasing forces applied by the leaf springs 64 and 65 attached to them, respectively. In other words, the first movable plate 62 and the second movable plate 63 can perform an oscillating motion in the Z direction by switching between energizing and de-energizing the electromagnet 61.

[0031] As shown in FIG. 4 , the first movable plate 62 has a central portion 621 and a pair of end portions 622, 623. The central portion 621 is a central portion of the first movable plate 62 in the X direction, and is formed into a rectangular shape with its long sides facing each other in the Y direction and its short sides facing each other in the X direction when viewed in the Z direction. The central portion 621 is shaped to cover the entire outer shape of the electromagnet 61 when viewed from the Z positive side. The pair of end portions 622, 623 are provided by connecting to both ends of the central portion 621 in the X direction, i.e., the short sides of the rectangular shape. In the example of FIG. 4 , one end portion 622 is located on the negative X direction side of the central portion 621, and the other end portion 623 is located on the positive X direction side of the central portion 621. The Y direction dimension of the pair of end portions 622, 623 is the same as that of the central portion 621. The X direction dimension of the pair of end portions 622, 623 is approximately the same. Furthermore, the thickness dimension in the Z direction of the pair of end portions 622, 623 is preferably formed to be thinner than that of the central portion 621, as shown in, for example, FIGS.

[0032] Pistons 71 and 81 are provided on the negative Z direction surfaces of the pair of end portions 622 and 623 of the first movable plate 62 so as to extend in the negative Z direction. The pistons 71 and 81 will be described later.

[0033] The second movable plate 63 has a central portion 631 and a pair of end portions 632, 633. The central portion 631 is a central portion of the second movable plate 63 in the X direction, and is formed into a rectangular shape with its long sides facing each other in the Y direction and its short sides facing each other in the X direction when viewed in the Z direction. The shape of the central portion 631 is formed to cover the entire outer shape of the electromagnet 61 when viewed from the negative Z direction side. The pair of end portions 632, 633 are provided by connecting to both ends of the central portion 631 in the X direction, i.e., the short sides of the rectangular shape. In the example of FIG. 4 , one end portion 632 is located on the negative X direction side of the central portion 631, and the other end portion 633 is located on the positive X direction side of the central portion 631. The Y direction dimension of the pair of end portions 632, 633 is the same as that of the central portion 631. The X direction dimension of the pair of end portions 632, 633 is approximately the same. Furthermore, the thickness dimension in the Z direction of the pair of end portions 632, 633 is preferably formed to be thinner than that of the central portion 631, as exemplified in, for example, FIGS.

[0034] Pistons 72 and 82 are provided on the Z positive side surfaces of the pair of end portions 632 and 633 of the second movable plate 63 so as to extend in the Z positive direction. Pistons 72 and 82 will be described later.

[0035] The pair of leaf springs 64, 65 are elastic members that bias in the Z direction, and include a first leaf spring 64 and a second leaf spring 65. The first leaf spring 64 is disposed on the Z positive side of the first movable plate 62, and the first movable plate 62 is attached to the first leaf spring 64. The second leaf spring 65 is disposed on the Z negative side of the second movable plate 63, and the second movable plate 63 is attached to the first leaf spring 64. The first leaf spring 64 and the second leaf spring 65 have the same shape and are disposed opposite each other in the Z direction. That is, as shown in FIG. 3 , the first leaf spring 64 and the second leaf spring 65 form the outermost parts of the resonant actuator 6 in the Z direction. In response to the attraction of the first movable plate 62 to the electromagnet 61, the first leaf spring 64 biases the first movable plate 62 in the direction opposite to the attraction (Z positive direction). Similarly, in response to the attraction of the second movable plate 63 to the electromagnet 61, the second leaf spring 65 biases the second movable plate 63 in the direction opposite to the attraction (negative Z direction).

[0036] 4, the first leaf spring 64 has a central portion 641, a pair of fixed end portions 642, and a pair of flexible portions 643. The central portion 641 is the center portion of the first leaf spring 64 in the X direction, and is a flat portion having a constant width in the Y direction and outer edges on both sides in the Y direction extending along the X direction. The first movable plate 62 is attached to the central portion 641 of the first leaf spring 64, and thus the first movable plate 62 and the first leaf spring 64 are installed so as to be movable integrally therewith.

[0037] The pair of fixed ends 642 are arranged at both ends of the first leaf spring 64 in the X direction, and are flat plate-like portions formed so that the outer edges in the X direction both extend in the Y direction. The pair of fixed ends 642 of the first leaf spring 64 are fixed to a support 9 (see FIG. 5, etc.) which is an example of a fixed object installed inside the housing 2, thereby fixing both end portions in the X direction.

[0038] The pair of flexible portions 643 are portions that are disposed between a central portion 641 and a pair of fixed end portions 642 along the X direction of the first leaf spring 64. The pair of flexible portions 643 are elastically deformed and bent so as to vary the relative positional relationship in the Z direction between the central portion 641, to which the first movable plate 62 is attached, and the pair of fixed end portions 642 that are fixed to the support body 9. The first leaf spring 64 can bias the first movable plate 62 attached to the central portion 641 by such elastic deformation of the pair of flexible portions 643.

[0039] 4 and other figures, the pair of flexible portions 643 are formed so that the width dimension perpendicular to the direction connecting the central portion 641 and the pair of fixed end portions 642 is relatively small so as to facilitate elastic deformation, and are curved in an S-shape when viewed in the Z direction. In order to make the amount of bending in the Y direction more uniform, the S-shaped curved portions are arranged on both sides of the axis of symmetry CA in the Y direction and are formed so as to be line-symmetrical with respect to the axis of symmetry CA. Note that the curved portions may have a shape other than an S-shape.

[0040] 4, the second leaf spring 65 has a central portion 651, a pair of fixed end portions 652, and a pair of flexible portions 653. The central portion 651 is the center portion of the second leaf spring 65 in the X direction, and is a flat portion having a constant width in the Y direction and outer edges on both sides in the Y direction extending along the X direction. The second movable plate 63 is attached to the central portion 651 of the second leaf spring 65, and thus the second movable plate 63 and the second movable plate 63 are installed so as to be movable together.

[0041] The pair of fixed ends 652 are arranged at both ends of the second leaf spring 65 in the X direction, and are flat plate-like portions formed so that the outer edges in the X direction both extend in the Y direction. The pair of fixed ends 652 of the second leaf spring 65 are fixed to a support 9 (see FIG. 5, etc.) which is an example of a fixed object installed inside the housing 2, thereby fixing both end portions in the X direction.

[0042] The pair of flexible portions 653 are portions that are disposed between a central portion 651 and a pair of fixed end portions 652 along the X direction of the second leaf spring 65. The pair of flexible portions 653 are elastically deformed and bent so as to vary the relative positional relationship in the Z direction between the central portion 651, to which the second movable plate 63 is attached, and the pair of fixed end portions 652 that are fixed to the support body 9. The second leaf spring 65 can bias the second movable plate 63 attached to the central portion 651 by such elastic deformation of the pair of flexible portions 653.

[0043] 4 and other figures, the pair of flexible portions 653 are formed so that the width dimension perpendicular to the direction connecting the central portion 651 and the pair of fixed end portions 652 is relatively small so as to facilitate elastic deformation, and are curved in an S-shape when viewed in the Z direction. In order to make the amount of bending in the Y direction more uniform, the S-shaped curved portions are arranged on both sides of the axis of symmetry CA in the Y direction and are formed so as to be line-symmetrical with respect to the axis of symmetry CA. Note that the curved portions may have a shape other than an S-shape.

[0044] 4, each element of the resonant actuator 6 is arranged so that the center position of each outer shape when viewed in the Z direction coincides with the center line CO of the pump 1. This allows the center of gravity of the resonant actuator 6 to be located near the center line CO of the pump 1, allowing the resonant actuator 6 to operate in a well-balanced manner.

[0045] In this embodiment, the first and second leaf springs 64 and 65 are respectively configured such that the first and second movable plates 62 and 63 are attached at the central portions 641 and 651, but the first and second movable plates 62 and 63 may be attached at any position other than the central portions in the X direction of the first and second leaf springs 64 and 65. Furthermore, the first and second leaf springs 64 and 65 are respectively configured such that they are fixed to the support 9 at a pair of fixed ends 642 and 652, but they may be fixed to the support 9 at any position other than both ends in the X direction.

[0046] Furthermore, in this embodiment, as described above, the first movable plate 62 and the second movable plate 63 are formed to have the same shape, and the first leaf spring 64 and the second leaf spring 65 are formed to have the same shape. The attachment position of the first movable plate 62 to the first leaf spring 64 is also the same as the attachment position of the second movable plate 63 to the second leaf spring 65. Therefore, the resonant frequency of the first movable part (the first movable plate 62 and the first leaf spring 64) is also the same as the resonant frequency of the second movable part (the second movable plate 63 and the second leaf spring 65). Therefore, if the switching frequency of the single electromagnet 61 disposed between the first movable part and the second movable part, which switches between a conductive state and a non-conductive state, is set to the same frequency as or close to the resonant frequency common to the first movable part and the second movable part, both the first movable part and the second movable part can be brought into a resonant state together. This allows the resonant actuator 6 of this embodiment to vibrate the movable part more efficiently.

[0047] The configuration of the first pump chamber 7 and the second pump chamber 8 of the pump 1 according to this embodiment will be described with reference to Figures 5 and 6. Figure 5 is a schematic diagram of the cross-sectional shape of the pump 1 according to this embodiment taken along the axis of symmetry CA. In Figure 5, elements of the pump 1 that are outside the resonant actuator 6, including the housing 2, are not shown.

[0048] As shown in FIG. 5 , the fourth flow path 54 and the fifth flow path 55 are holes formed in a support 9, which is an example of a fixed object installed inside the housing 2. The support 9 may be, for example, a block-shaped component fixed to the inner wall surface of the housing 2. The other flow paths of the flow path 5, other than the fourth flow path 54 and the fifth flow path 55, are also holes formed in the support 9. In the example of FIG. 5 , the support 9 on which the flow path 5 is provided and the support 9 to which the pair of fixed ends 642 of the first leaf spring 64 and the pair of fixed ends 652 of the second leaf spring 65 of the resonant actuator 6 are fixed are illustrated as an integrated component. However, separate components may be integrally connected to each other. Similarly, the first to eighth flow paths 51 to 58 constituting the flow path 5 may be provided in separate supports, and these supports may be connected to form the flow path 5.

[0049] 5 is a cross section taken along the axis of symmetry CA of the pump 1, and therefore, as is clear from reference to FIG. 2, it is a cross section of a portion of the fourth flow path 54 where the first pump chamber 7 is disposed, and a portion of the fifth flow path 55 where the second pump chamber 8 is disposed. As shown in FIG. 5, the first pump chamber 7 and the second pump chamber 8 are provided with cylinders 73 and 83, respectively, which communicate with each other along the Z direction.

[0050] The cylinder 73 of the first pump chamber 7 is formed to open on the Z positive side and the Z negative side of the support body 9. Furthermore, in this embodiment, the first piston 71 provided in the first movable plate 62 and the second piston 72 provided in the second movable plate 63 are disposed in positions where their axial directions overlap with the first pump chamber 7, i.e., positions where they overlap with the axial direction of the cylinder 73. For this reason, as shown in FIG. 5 , the first piston 71 is slidably inserted into the cylinder 73 from the opening on the Z positive side, and the second piston 72 is slidably inserted into the cylinder 73 from the opening on the Z negative side.

[0051] The cylinder 83 of the second pump chamber 8 is formed to open on the Z positive side and the Z negative side of the support body 9. Furthermore, in this embodiment, the first piston 81 provided in the first movable plate 62 and the second piston 82 provided in the second movable plate 63 are disposed at positions where their axial directions overlap with the second pump chamber 8, i.e., positions where they overlap with the axial direction of the cylinder 83. For this reason, as shown in FIG. 5 , the first piston 81 is slidably inserted into the cylinder 83 from the opening on the Z positive side, and the second piston 82 is slidably inserted into the cylinder 83 from the opening on the Z negative side.

[0052] These first pistons 71, 81 and second pistons 72, 82 are respectively mounted on the first movable plate 62 and the second movable plate 63. Therefore, in conjunction with the vibration motion of the first movable plate 62 and the second movable plate 63 in the Z direction caused by energization control of the electromagnet 61, the first pistons 71, 81 and the second pistons 72, 82 slide within the respective cylinders 73, 83, repeatedly moving toward and away from each other. This allows the volumes of the first pump chamber 7 and the second pump chamber 8 to increase or decrease.

[0053] FIG. 6 is a schematic diagram of a cross-sectional shape of the fourth flow path 54 of the pump 1 according to the embodiment, taken along the axial direction. As shown in FIG. 6 , an inlet valve 74 and a discharge valve 75 are provided in the fourth flow path 54, respectively, on the upstream and downstream sides of the first pump chamber 7. When the first piston 71 and the second piston 72 approach each other in the cylinder 73 and the volume of the first pump chamber 7 decreases, the inlet valve 74 closes to prevent fluid from flowing into the first pump chamber 7 from the upstream side of the fourth flow path 54, and the discharge valve 75 opens to discharge fluid from the first pump chamber 7 to the downstream side of the fourth flow path 54. On the other hand, when the first piston 71 and the second piston 72 move away from each other in the cylinder 73 and the volume of the first pump chamber 7 increases, the inlet valve 74 opens to allow fluid to flow into the first pump chamber 7 from the upstream side of the fourth flow path 54, and the discharge valve 75 closes to prevent fluid from being discharged from the first pump chamber 7 to the downstream side of the fourth flow path 54.

[0054] 6 illustrates a configuration for achieving this effect in which both suction valve 74 and discharge valve 75 have a sphere disposed upstream of fourth flow path 54 so as to be able to seal the flow path, and a spring disposed downstream for biasing this sphere upstream. However, the configurations of suction valve 74 and discharge valve 75 other than those shown in FIG. 6 may also be used.

[0055] In this embodiment, the volume of the first pump chamber 7 is the area between the lower end surface of the first piston 71 and the upper end surface of the second piston 72 in the cylinder 73. This volume increases or decreases in accordance with the up and down movement of the first piston 71 and the second piston 72 in the cylinder 73.

[0056] 6 illustrates the cross section of the fourth flow path 54 to explain the configuration of the first pump chamber 7, but the second pump chamber 8 in the fifth flow path 55 has a similar configuration. That is, the area between the lower end surface of the first piston 81 and the upper end surface of the second piston 82 in the cylinder 83 defines the volume of the second pump chamber 8. This volume increases or decreases in accordance with the up and down movement of the first piston 81 and the second piston 82 in the cylinder 83.

[0057] [Pump operation] The operation of the pump 1 according to the embodiment will be described with reference to FIGS.

[0058] Fig. 7 is a schematic diagram showing the operation of the pump 1 when the coil is energized. Fig. 8 is a schematic diagram showing the periphery of the first pump chamber 7 in the state shown in Fig. 7. The overview of Figs. 7 and 8 is similar to Figs. 5 and 6.

[0059] As shown in Fig. 7, when coil 612 of electromagnet 61 is energized, a magnetic field M1 is generated that passes through the center of coil 612. Magnetic field M1 generated by coil 612 is further strengthened by winding portion 611A of core 611 that is installed to pass through the center of coil 612. In the example of Fig. 7, magnetic field M1 is generated inside winding portion 611A toward the positive X direction.

[0060] The magnetic field M1 thus generated branches into the Z-positive and Z-negative directions along the protruding direction of one of the widened portions 611B disposed on the X-positive side of the winding portion 611A of the core 611. Next, the magnetic field M1 flows toward the X-negative direction inside the first movable plate 62 and the second movable plate 63, which are disposed opposite the upper and lower end faces of the widened portion 611B, respectively. Then, the magnetic fields M1 flow toward the Z-negative direction from the upper and lower end faces of the other widened portion 611B disposed on the X-negative side of the winding portion 611A, inside the widened portion 611B, respectively, toward the center in the Z direction, merge, and then flow back into the winding portion 611A. In other words, the magnetic field M1 illustrated in FIG. 7 flows clockwise on the first movable plate 62 side and counterclockwise on the second movable plate 63 side when viewed from the Y-negative side.

[0061] By generating such a magnetic field M1, the first movable plate 62 is attracted to the electromagnet 61 and moves in the negative Z direction, as shown by arrow A in Fig. 7. Similarly, the second movable plate 63 is attracted to the electromagnet 61 and moves in the positive Z direction, as shown by arrow B.

[0062] Due to this movement of the first movable plate 62 and the second movable plate 63 toward the side attracted to the electromagnet 61, in the first pump chamber 7, the first piston 71 slides in the negative Z direction inside the cylinder 73 as indicated by arrow C. Also, the second piston 72 slides in the positive Z direction inside the cylinder 73 as indicated by arrow D. As a result, the lower end surface of the first piston 71 and the upper end surface of the second piston 72 approach each other, and the volume of the first pump chamber 7 decreases.

[0063] Similarly, in the second pump chamber 8, the first piston 81 slides in the negative Z direction within the cylinder 83 as indicated by arrow E. Also, the second piston 82 slides in the positive Z direction within the cylinder 83 as indicated by arrow F. As a result, the lower end surface of the first piston 81 and the upper end surface of the second piston 82 approach each other, and the volume of the second pump chamber 8 decreases.

[0064] Ideally, the first movable plate 62 and the second movable plate 63 are both moved parallel to the Z direction by the magnetic field M1. Therefore, the sliding distance of the two first pistons 71, 81 installed on the first movable plate 62 is the same as the sliding distance of the two second pistons 72, 82 installed on the second movable plate 63. Therefore, the reduction amounts of the volumes of the first pump chamber 7 and the second pump chamber 8 are also the same.

[0065] Furthermore, as the first movable plate 62 moves toward the side where it is attracted to the electromagnet 61, the central portion 641 of the first leaf spring 64 to which the first movable plate 62 is attached also moves integrally with the first movable plate 62 in the direction of arrow A. At this time, since the fixed end 642 of the first leaf spring 64 is fixed to the support 9, the central portion 641 is displaced in the negative Z direction relative to the fixed end 642. In FIG. 7, the Z-direction position of the first leaf spring 64 in the steady state shown in FIG. 5 is indicated by a dotted line S1. As a result of this displacement, the flexible portion 643 disposed between the central portion 641 and the fixed end 642 is elastically deformed in the negative Z direction, which generates a biasing force f1 in the flexible portion 643 for elastically returning to the positive Z direction, as indicated by the dotted arrow f1 in FIG. 7.

[0066] Similarly, as the second movable plate 63 moves toward the side where it is attracted to the electromagnet 61, the central portion 651 of the second leaf spring 65 to which the second movable plate 63 is attached also moves integrally with the second movable plate 63 in the direction of arrow B. At this time, since the fixed end 652 of the second leaf spring 65 is fixed to the support 9, the central portion 651 is displaced in the positive Z direction relative to the fixed end 652. In FIG. 7, the Z-direction position of the second leaf spring 65 in the steady state shown in FIG. 5 is indicated by a dotted line S2. As a result of this displacement, the flexible portion 653 disposed between the central portion 651 and the fixed end 652 is elastically deformed in the positive Z direction. As a result, a biasing force f2 is generated in the flexible portion 653, causing it to elastically return in the negative Z direction, as indicated by the dotted arrow f2 in FIG. 7.

[0067] When the first pistons 71, 81 and the second pistons 72, 82 move closer to each other as shown in FIG. 7, the volumes of the first pump chamber 7 and the second pump chamber 8 decrease. As a result, as shown in FIG. 8, in the first pump chamber 7, the spherical bodies of the suction valve 74 and the discharge valve 75 are pressed toward the upstream and downstream sides of the fourth flow path 54, respectively, by the fluid in the first pump chamber 7. At this time, the spherical body of the suction valve 74 blocks the upstream side of the fourth flow path 54, so the suction valve 74 is closed. On the other hand, the spherical body of the discharge valve 75 is movable downstream as shown by arrow G, so the discharge valve 75 is opened. As a result, the fluid in the first pump chamber 7 is pressurized and discharged to the downstream side of the fourth flow path 54.

[0068] As described above, the amount of reduction in the volume of the first pump chamber 7 and the second pump chamber 8 is the same, so in the second pump chamber 8, the fluid in the second pump chamber 8 is pressurized and discharged downstream of the fifth flow path 55, similar to the operation of the first pump chamber 7 shown in Figure 7.

[0069] Fig. 9 is a schematic diagram showing the operation of the pump 1 when the coil is switched from energized to de-energized as shown in Fig. 7. Fig. 10 is a schematic diagram showing the periphery of the first pump chamber 7 in the state shown in Fig. 9. The overview of Figs. 9 and 10 is similar to Figs. 5 and 6.

[0070] As shown in FIG. 9, when the coil 612 of the electromagnet 61 is switched from the energized state shown in FIG. 7 to the de-energized state, the magnetic field M1 generated around the electromagnet 61 disappears.

[0071] When the magnetic field M1 disappears, the attractive force that the first movable plate 62 and the second movable plate 63 received from the electromagnet 61 also disappears. Therefore, the first leaf spring 64 operates to return to its original position due to the biasing force f1 generated in the flexible portion 643 of the first leaf spring 64, as indicated by the dotted arrow in FIG. 7 , and the first movable plate 62 also moves in the positive Z direction in response to this operation. However, because the attractive force that was balanced with the biasing force f1 has disappeared, neither the first movable plate 62 nor the first leaf spring 64 remains stationary at the normal position S1, but moves further in the positive Z direction. Finally, as indicated by the arrow H in FIG. 9 , they move in the positive Z direction from the normal position S1 by an amount equal to the amount of movement due to the attraction of the electromagnet 61. Similarly, as indicated by arrow I, the second movable plate 63 and the second leaf spring 65 also move from the steady position S2 toward the negative Z direction due to the biasing force f2 toward the negative Z direction that has been generated in the flexible portion 653.

[0072] As a result of this movement of the first movable plate 62 and the second movable plate 63 away from the electromagnet 61, in the first pump chamber 7, the first piston 71 slides in the positive Z direction within the cylinder 73 as indicated by the arrow J. Also, the second piston 72 slides in the negative Z direction within the cylinder 73 as indicated by the arrow K. As a result, the lower end surface of the first piston 71 and the upper end surface of the second piston 72 move away from each other, and the volume of the first pump chamber 7 increases.

[0073] Similarly, in the second pump chamber 8, the first piston 81 slides in the positive Z direction within the cylinder 83 as indicated by the arrow L. Also, the second piston 82 slides in the negative Z direction within the cylinder 83 as indicated by the arrow M. As a result, the lower end surface of the first piston 81 and the upper end surface of the second piston 82 move away from each other, and the volume of the second pump chamber 8 increases.

[0074] Ideally, the first movable plate 62 and the second movable plate 63 move parallel to each other in the Z direction due to the biasing forces f1 and f2 of the flexible portions 643 and 653. Therefore, the sliding distance of the two first pistons 71 and 81 installed on the first movable plate 62 is the same as the sliding distance of the two second pistons 72 and 82 installed on the second movable plate 63. Therefore, the increase in volume of the first pump chamber 7 and the second pump chamber 8 is also the same.

[0075] 9, when the first pistons 71, 81 and the second pistons 72, 82 move away from each other, the volumes of the first pump chamber 7 and the second pump chamber 8 increase. As a result, as shown in FIG. 10, in the first pump chamber 7, the balls of the suction valve 74 and the discharge valve 75 are each sucked toward the cylinder 73 by the fluid in the first pump chamber 7. At this time, the ball of the discharge valve 75 moves to block the upstream side of the fourth flow path 54 as indicated by arrow N, so the discharge valve 75 is closed. On the other hand, the ball of the suction valve 74 is able to move downstream as indicated by arrow O, so the suction valve 74 is opened. As a result, the fluid upstream of the fourth flow path 54 is sucked into the first pump chamber 7.

[0076] As described above, the increase in volume of the first pump chamber 7 and the second pump chamber 8 is the same, so in the second pump chamber 8, the fluid upstream of the fifth flow path 55 is sucked into the second pump chamber 8, similar to the operation of the first pump chamber 7 shown in Figure 10.

[0077] In the pump 1 of this embodiment, the pump 1 can be driven by controlling the supply of electricity to the coil 612 of the electromagnet 61 so as to alternate between the state when the coil is energized (first state) shown in Figures 7 and 8 and the state when the coil is not energized (second state) shown in Figures 9 and 10.

[0078] With this control, the pressure of the fluid discharged from the pump 1 can be adjusted according to the amount and speed of movement of the first pistons 71, 81 and the second pistons 72, 82. To adjust the pressure, it is necessary to adjust the amount and speed of movement of the first movable plate 62 and the second movable plate 63 on which the first pistons 71, 81 and the second pistons 72, 82 are installed. To adjust the movement of the movable plates 62, 63, it is necessary to adjust the strength (magnetic flux density, etc.) of the magnetic field M1 generated by the electromagnet 61. To adjust the magnetic field M1, it is necessary to control the magnitude of the current flowing through the coil 612 of the electromagnet 61. In other words, with the pump 1 of this embodiment, it is possible to control the discharge of fluid at a desired pressure by controlling the value of the current flowing through the coil 612 of the resonant actuator 6.

[0079] Alternatively, in the pump 1 of this embodiment, it is possible to control the discharge of fluid at a desired pressure by adjusting various structural elements, such as the number of turns of the conducting wire of the coil 612 of the electromagnet 61, the X-direction and Y-direction dimensions of the wound portion 611A of the core 611, the Z-direction protrusion amount and X-direction and Y-direction dimensions of the widened portion 611B of the core 611, the area and shape of the first movable plate 62 and the second movable plate 63 as viewed in the Z direction, and the spring constants of the first leaf spring 64 and the second leaf spring 65.

[0080] The pump 1 of this embodiment includes an electromagnet 61, a first movable plate 62 and a second movable plate 63 that are attracted to the electromagnet 61 by a magnetic field M1 generated by energizing the electromagnet 61, and a first leaf spring 64 and a second leaf spring 65 to which the first movable plate 62 and the second movable plate 63 are attached, respectively, and which urge the first movable plate 62 and the second movable plate 63 in a direction opposite to the attracting action of the first movable plate 62 and the second movable plate 63 to the electromagnet 61 in response to the attracting action of the first movable plate 62 and the second movable plate 63. and second leaf spring 65, a flow path 5 through which a fluid flows, a first pump chamber 7 and a second pump chamber 8 provided on the flow path 5, and an electromagnet 61 that operates to reduce the volume of the first pump chamber 7 and the second pump chamber 8 in response to the suction action of the first movable plate 62 and the second movable plate 63, and when the electromagnet 61 is switched to a non-energized state after the suction action, the electromagnet 61 ... The pump is provided with: a first piston (71, 81) and a second piston (72, 82) as an example of a volume-changing member that operates to increase the volume of the first pump chamber (7) and the second pump chamber (8) in response to the moving away from the stone (61); an intake valve (74) that is provided upstream of the flow path (5) in the first pump chamber (7) and the second pump chamber (8) and opens when the first piston (71, 81) and the second piston (72, 82) move in the direction of increasing the volume of the first pump chamber (7) and the second pump chamber (8) to draw fluid from the upstream side of the flow path (5) into the first pump chamber (7) and the second pump chamber (8); and a discharge valve (75) that is provided downstream of the flow path (5) in the first pump chamber (7) and the second pump chamber (8) and opens when the first piston (71, 81) and the second piston (72, 82) move in the direction of reducing the volume of the first pump chamber (7) and the second pump chamber (8) to discharge fluid from the first pump chamber (7) and the second pump chamber (8) to the downstream side of the flow path (5).

[0081] Here, among the above components, the electromagnet 61 can also be expressed as a “fixed part.” The first and second movable plates 62 and 63, and the first and second leaf springs 64 and 65 can also be expressed as a “movable part that performs a vibrating motion in which it is attracted to the fixed part by a magnetic field generated when the electromagnet 61 is energized, and moves away from the fixed part by a biasing force generated when the electromagnet 61 is not energized.”

[0082] With this configuration, the fixed part (electromagnet 61) generates vibrations in the movable part (first movable plate 62, second movable plate 63, first leaf spring 64, and second leaf spring 65), causing the first piston 71 and the second piston 72 installed in the first pump chamber 7 to slide synchronously within the common cylinder 73. In other words, the resonant actuator 6 can be used as a drive source for the pump 1. This reduces the amount of piston movement required to increase or decrease the volume of the first pump chamber 7 and the second pump chamber 8 compared to conventional solenoid-driven metering pumps, thereby reducing vibration during operation of the pump 1. Furthermore, by setting the switching frequency for switching between the energized and de-energized states of the electromagnet 61 to the same frequency as or near the resonant frequency of the movable part, which is a vibrating element, the movable part can be placed in a resonant state. As a result, the resonant actuator 6 efficiently vibrates the movable part by utilizing the resonance of the movable part in addition to the attraction of the movable part by the electromagnet 61 when the electromagnet 61 is energized. As a result, the efficiency of the pump 1 of this embodiment can be improved.

[0083] In the pump 1 of this embodiment, the first movable plate 62 and the second movable plate 63 are disposed opposite each other with the electromagnet 61 interposed therebetween. The first movable plate 62 and the second movable plate 63 are attached to the first leaf spring 64 and the second leaf spring 65, respectively. That is, the first leaf spring 64 and the second leaf spring 65 are also disposed opposite each other with the electromagnet 61 interposed therebetween. The first pistons 71 and 81 are mounted on the first movable plate 62 and move in conjunction with the movement of the first movable plate 62. The second pistons 72 and 82 are mounted on the second movable plate 63 and move in conjunction with the movement of the second movable plate 63.

[0084] With this configuration, a pair of opposing movable parts (first movable plate 62 and first leaf spring 64, second movable plate 63 and second leaf spring 65) can be vibrated in synchronization with a single electromagnet 61. At this time, since the pair of movable parts are arranged opposite each other with the electromagnet 61 in between, the directions in which they are attracted by the electromagnet 61 are opposite. Therefore, the vibration directions of the pair of movable parts are out of phase. This makes it possible to offset and cancel vibrations generated in the pump 1 by the operation of each movable part.

[0085] In addition, in the pump 1 of this embodiment, the first movable part (first movable plate 62 and first leaf spring 64) and the second movable part (second movable plate 63 and second leaf spring 65) are arranged opposite each other with the fixed part (electromagnet 61) in between. The first pistons 71 and 81 are linked to the operation of the first movable part, and the second pistons 72 and 82 are linked to the operation of the second movable part. The first piston 71 and the second piston 72 are installed in the same first pump chamber 7. Similarly, the first piston 81 and the second piston 82 are installed in the same second pump chamber 8.

[0086] With this configuration, a common pump chamber can be used for the pair of pistons, so only one flow path (fourth flow path 54) and one valve (suction valve 74, discharge valve 75) are required for each pair of first piston 71 and second piston 72. Similarly, only one flow path (fifth flow path 55) and one valve (suction valve 74, discharge valve 75) are required for each pair of first piston 81 and second piston 82. This reduces the number of parts and simplifies the structure of pump 1. Furthermore, because the pump chamber is common, the reaction force acting on the pair of pistons installed in this pump chamber is the same, and there is less misalignment in the movements of the pair of moving parts arranged opposite each other. This allows the number of pump chambers to be increased while reducing the number of parts, thereby improving pump efficiency.

[0087] Here, the effect of core 611 of electromagnet 61 according to this embodiment will be described with reference to Fig. 11 in addition to Fig. 7. Fig. 11 is a schematic diagram showing magnetic field M2 generated in electromagnet 61A using flat core 611C as a comparative example.

[0088] In the comparative example of Fig. 11, electromagnet 61A has a flat core 611C. Core 611C of the comparative example differs from core 611 of the embodiment in that it does not have widened portion 611B as shown in Fig. 7 and other figures. Core 611C is formed so that the dimension in the Z direction is uniform throughout the entire X direction. In other words, core 611C has a shape in which wound portion 611A of core 611 of the embodiment extends to both sides of the range in the X direction where widened portion 611B is located.

[0089] 11 , when a magnetic field M2 is generated inside the core 611C in the X-positive direction by energizing the coil 612, this magnetic field M2 first advances in the X-positive direction from the end of the core 611C on the X-positive side into the space of the resonant actuator 6. Then, it branches off toward the Z-positive side and the Z-negative side, curves, reverses its direction, enters the interior from the X-positive side ends of the first movable plate 62 and the second movable plate 63, and heads toward the X-negative side. Then, it advances again in the X-negative direction into the space of the resonant actuator 6 from the X-negative side ends of the first movable plate 62 and the second movable plate 63, curves toward the Z-negative side and the Z-positive side, reverses its direction to the X-positive side, and merges with the magnetic field M2 before flowing into the X-negative side end of the core 611C.

[0090] 11 is the same as the magnetic field M1 of the embodiment shown in Fig. 7 in that, when viewed from the Y negative direction, the magnetic field M2 of the comparative example flows clockwise on the first movable plate 62 side and counterclockwise on the second movable plate 63 side. However, the magnetic field M2 of the comparative example flows more in the space of the resonant actuator 6 than the magnetic field M1 of the embodiment, that is, the air gap is larger, and therefore the magnetic resistance tends to increase.

[0091] 7, the electromagnet 61 of this embodiment is provided with an expanded width portion 611B in the core 611, so that the air gap in the magnetic field M1 can be limited to the gap between the upper end surface of the expanded width portion 611B and the first movable plate 62, and the gap between the lower end surface of the expanded width portion 611B and the second movable plate 63. This reduces the air gap in the magnetic field M1, and reduces the magnetic resistance, so that the magnetic force can be generated more efficiently than in the comparative example.

[0092] In this embodiment, the core 611 of the electromagnet 61 is formed by stacking multiple electromagnetic steel plates in the Y direction, as shown in Figures 3 and 4. Adjacent electromagnetic steel plates are bonded together with an adhesive, and this adhesive portion forms an air gap, which creates magnetic resistance that makes it difficult for magnetic flux to flow. Since the magnetic flux generated by the coil 612 flows through the core 611 toward the movable plates 62 and 63, if the stacking direction is the Y direction as in this embodiment, the air gap is positioned parallel to the flow of the magnetic flux, which results in less obstruction to the flow of magnetic flux and improved energy transmission efficiency.

[0093] On the other hand, in a configuration in which the lamination direction is 90 degrees different from that of this embodiment, that is, in which the lamination direction is the X direction, an air gap is placed in a position that obstructs the flow of magnetic flux, resulting in a decrease in efficiency.

[0094] Next, the effects of the shapes of the movable plates 62, 63 and the leaf springs 64, 65 in this embodiment will be described with reference to Fig. 12. Fig. 12 is a plan view of the internal structure of the housing 2 of the pump 1 as viewed from the Z positive side. Fig. 12 illustrates the interior of the housing 2 as viewed from the first leaf spring 64 side, with the main surface of the housing 2 on the Z positive side removed from the pump 1 shown in Fig. 1.

[0095] If the direction (Y direction) perpendicular to the direction (X direction) of the magnetic field M1 generated by the electromagnet 61 is defined as the width direction, as shown in Fig. 12, the width dimension W1 of at least the flexible portion 643 of the first leaf spring 64 is larger than the width dimension W2 of the first movable plate 62. The same applies to the relationship between the second movable plate 63 and the second leaf spring 65, which are hidden at the back of Fig. 12, and the width dimension W1 of at least the flexible portion 653 of the second leaf spring 65 is larger than the width dimension W2 of the second movable plate 63.

[0096] As described with reference to FIG. 7 , when the electromagnet 61 is energized during operation of the resonant actuator 6, the first movable plate 62 and the second movable plate 63 ideally move parallel to each other in a direction (Z direction) toward the electromagnet 61 due to the magnetic field M1 generated by the electromagnet 61. However, if the magnetic field M1 has an uneven magnetic flux density across the width of the movable plates 62 and 63, the first movable plate 62 and the second movable plate 63 may be twisted during operation, such as tilting in the X direction or the Y direction. Therefore, by forming the width dimension W1 of the leaf springs 64 and 65 larger than that of the movable plates 62 and 63 as in this embodiment, the leaf springs 64 and 65 can more easily absorb the twisting of the movable plates 62 and 63 during operation, thereby enabling more stable translation of the first movable plate 62 and the second movable plate 63. As a result, the pump 1 of this embodiment, which uses the resonant actuator 6 as a drive source, can reduce noise and vibration.

[0097] Furthermore, the first pump chamber 7 and the second pump chamber 8 are disposed opposite each other at positions where a pair of first pistons 71, 81 are provided on both ends of the first movable plate 62 in the direction of the magnetic field M1 (X direction). Similarly, the second movable plate 63 is disposed opposite each other at positions where a pair of second pistons 72, 82 are provided on both ends of the second movable plate 63 in the direction of the magnetic field M1 (X direction). In this configuration having two pump chambers, two pistons are provided on one movable plate. Therefore, when the relationship between the widthwise dimension W1 of the leaf springs 64, 65 and the widthwise dimension W2 of the movable plates 62, 63 is satisfied, sliding of the two pistons provided on one movable plate relative to the pump chambers 7, 8 can be stabilized, thereby particularly effective in suppressing twisting of the movable plates 62, 63.

[0098] Next, the effects of the arrangement of the first pump chamber 7 and the second pump chamber 8 will be described. As shown in FIGS. 2 and 7 , among the flow paths 5 of the pump 1, the fourth flow path 54 including the first pump chamber 7 is arranged adjacent to a position opposite (on the negative X-direction side) the wound portion 611A of the core 611 of the electromagnet 61, across the widened portion 611B on the negative X-direction side of the core 611, and the flow direction is arranged along the width direction (Y direction). Similarly, the fifth flow path 55 including the second pump chamber 8 among the flow paths 5 of the pump 1 is arranged adjacent to a position opposite (on the positive X-direction side) the wound portion 611A of the core 611, across the widened portion 611B on the positive X-direction side of the core 611 of the electromagnet 61, and the flow direction is arranged along the width direction (Y direction).

[0099] Therefore, the first piston 71 inserted into the first pump chamber 7 is disposed adjacent to a position on the opposite side (X-negative direction side) of the wound portion 611A of the first movable plate 62, across the widened portion 611B on the X-negative direction side of the electromagnet 61. The second piston 72 also inserted into the first pump chamber 7 is disposed adjacent to a position on the opposite side (X-negative direction side) of the wound portion 611A of the second movable plate 63, across the widened portion 611B on the X-negative direction side of the electromagnet 61. Similarly, the first piston 81 inserted into the second pump chamber 8 is disposed adjacent to a position on the opposite side (X-positive direction side) of the wound portion 611A of the first movable plate 62, across the widened portion 611B on the X-positive direction side of the electromagnet 61. The second piston 82, which is also inserted into the second pump chamber 8, is positioned adjacent to the second movable plate 63 on the opposite side (X-positive side) of the winding portion 611A, sandwiching the widened portion 611B on the X-positive side of the electromagnet 61.

[0100] By providing widened portions 611B at both ends in the X direction of core 611 of electromagnet 61, a magnetic field M1 is generated such that magnetic flux passes through the upper and lower end surfaces of widened portion 611B in a concentrated manner, as shown in Fig. 7. That is, when electromagnet 61 is energized, the first movable plate 62 receives the strongest attractive force at a portion facing the upper end surface of widened portion 611B, and the second movable plate 63 receives the strongest attractive force at a portion facing the lower end surface of widened portion 611B. Therefore, by arranging first pistons 71, 81 and second pistons 72, 82 adjacent to widened portion 611B, each piston can be arranged near a portion of first movable plate 62 and second movable plate 63 that receives the strongest attractive force from electromagnet 61. This makes it possible to efficiently apply external force in the sliding direction from the first movable plate 62 and the second movable plate 63 to the first pistons 71, 81 and the second pistons 72, 82, thereby improving the operating efficiency of both the first pump chamber 7 and the second pump chamber 8.

[0101] Furthermore, by arranging the first pistons 71, 81 and the second pistons 72, 82 near the portions of the first movable plate 62 and the second movable plate 63 that receive the strongest attractive force from the electromagnet 61, it is possible to prevent the movement directions of the first pistons 71, 81 and the second pistons 72, 82 from being twisted during the attraction operation due to the attractive force generated when the electromagnet 61 is energized. This makes it possible to align the movement directions of the first pistons 71, 81 and the second pistons 72, 82 with the axial direction (Z direction) of the cylinders 73, 83 of the respective pump chambers 7, 8, thereby further improving the operating efficiency of the first pump chamber 7 and the second pump chamber 8. As a result, the pump 1 of this embodiment can achieve improved performance and high efficiency in a configuration that uses the resonant actuator 6 as a drive source.

[0102] Furthermore, the first pump chamber 7 is disposed adjacent to a position on the opposite side (X negative direction) of the wound portion 611A of the core 611 of the electromagnet 61, with one of the pair of widened portions 611B of the core 611 sandwiched therebetween, and the second pump chamber 8 is disposed adjacent to a position on the opposite side (X positive direction) of the wound portion 611A, with the other of the pair of widened portions 611B sandwiched therebetween. In this configuration having two pump chambers, two pistons are installed on one movable plate. Therefore, by arranging the pump chambers 7, 8 adjacent to the widened portion 611B, it is possible to more easily equalize the external forces applied to the two pistons installed on one movable plate, and it is possible to more easily synchronize the sliding of the pistons in the pump chambers 7, 8. This particularly improves the operating efficiency of the pump chambers.

[0103] As shown in FIG. 2 and other figures, it is preferable that both the first pump chamber 7 and the second pump chamber 8 be arranged on the axis of symmetry CA of the housing 2. As shown in FIG. 7 and other figures, the coil 612 of the electromagnet 61 is arranged so that its central axis coincides with the axis of symmetry CA, and therefore, magnetic flux tends to be most concentrated on the axis of symmetry CA near the center of the coil 612. Therefore, the first movable plate 62 and the second movable plate 63 are likely to receive the strongest attractive force from the electromagnet 61 on the axis of symmetry CA. Therefore, if the first pump chamber 7 and the second pump chamber 8 are arranged on the axis of symmetry CA, the first pistons 71, 81 and the second pistons 72, 82 are also arranged on the axis of symmetry CA. This makes it possible for the first movable plate 62 and the second movable plate 63 to efficiently apply an external force in the sliding direction to the first pistons 71, 81 and the second pistons 72, 82, thereby further improving the operating efficiency of the first pump chamber 7 and the second pump chamber 8.

[0104] [Liquid-cooled heat sink configuration] The configurations of liquid cooling heat sinks 100A, 100B, and 100C according to this embodiment will be described with reference to Figures 13 to 15. Below, the configurations of three types of liquid cooling heat sinks 100A, 100B, and 100C will be illustrated.

[0105] Each of the liquid-cooled heat sinks 100A, 100B, and 100C is a device that cools the heat-generating element 200 by absorbing heat from the heat-generating element 200 using a fluid flowing through a flow path 5. Furthermore, each of the liquid-cooled heat sinks 100A, 100B, and 100C uses the pump 1 according to this embodiment described with reference to FIGS. 1 to 12 as a pump that pumps out the fluid through the flow path 5. Note that in FIGS. 13 to 15, the internal structure of the pump 1 is not shown, and only the outline of the arrangement of the flow path 5 is schematically illustrated.

[0106] 13 is a diagram showing a schematic configuration of a first example of a liquid-cooled heat sink 100A according to an embodiment. As shown in FIG. 13, the liquid-cooled heat sink 100A of the first example includes a heat absorption part 101. The heat absorption part 101 is an element that cools the heat generating element 200 by absorbing heat generated from the heat generating element 200. The heat absorption part 101 is made of a material with high thermal conductivity, such as copper or aluminum, so as to improve the ability to absorb heat from the heat generating element 200.

[0107] The heat absorption part 101 is disposed between the housing 2 of the pump 1 and the heating element 200. The heat absorption part 101 is preferably formed so as to be in surface contact with the heating element 200 in order to increase the contact area with the heating element 200 and improve heat absorption efficiency. Since the housing 2 of the pump 1 according to this embodiment has a substantially rectangular parallelepiped shape as described above, in the example of FIG. 13 , the shape of the heat absorption part 101 is also a substantially rectangular parallelepiped shape similar to the housing 2. Furthermore, in this embodiment, the heat absorption part 101 is fixed to the negative Z direction side of the housing 2 of the pump 1 and is formed integrally with the housing 2.

[0108] Meanwhile, in this embodiment, the heat generating element 200 also has a main surface 200A facing the positive Z direction, and the other main surface 101B of the pair of main surfaces of the heat absorbing part 101 facing the negative Z direction is in surface contact with the main surface 200A of the heat generating element 200. This increases the contact area between the heat absorbing part 101 and the heat generating element 200, thereby improving the heat absorption efficiency.

[0109] In the first example of FIG. 13 , the flow path 5 includes an internal flow path 5A and an extension flow path 5B. The internal flow path 5A is the portion of the flow path 5 that is built into the housing 2 of the pump 1. The upstream-most end of the internal flow path 5A is connected to the intake port 3. The downstream-most end of the internal flow path 5A is connected to the exhaust port 4. In the basic configuration of the pump 1 described with reference to FIGS. 1 to 12 , the internal flow path 5A in FIG. 13 constitutes the entire flow path 5. Therefore, although not shown in FIG. 13 , pump chambers 7 and 8 are also provided above the internal flow path 5A in the configuration of FIG. 13 . Similarly, although not shown in FIG. 13 , a resonant actuator 6 is also provided inside the housing 2 of the pump 1 in the configuration of FIG. 13 . Furthermore, in the configuration of FIG. 13 , the vibration action of the resonant actuator 6 imparts energy to the fluid in the flow path 5 in the pump chambers 7 and 8, causing the fluid to move from the upstream side to the downstream side of the flow path 5. This maintains the flow of the fluid in the flow path 5. The basic configuration of the pump 1 is the same as that of a second example shown in FIG. 14 and a third example shown in FIG. 15, which will be described later.

[0110] The extension flow path 5B is a portion of the flow path 5 that is arranged inside the heat absorption unit 101. The extension flow path 5B is provided by extending from the internal flow path 5A. The upstream end of the extension flow path 5B is connected to the internal flow path 5A, so that the fluid flows in from the upstream internal flow path 5A. The downstream end of the extension flow path 5B is connected to the internal flow path 5A, so that the fluid flows out to the downstream internal flow path 5A. That is, in the first example of FIG. 13 , the flow path 5 is configured so that it starts from the intake port 3 and first passes through the internal flow path 5A inside the housing 2, then passes through the inside of the heat absorption unit 101 via the extension flow path 5B, and finally returns to the inside of the housing 2 and connects to the exhaust port 4 via the internal flow path 5A.

[0111] In the first example of the liquid-cooled heat sink 100A shown in FIG. 13, the heat-generating element 200 can be cooled by the fluid flowing through the extended flow path 5B of the heat absorption unit 101 absorbing heat from the heat-generating element 200. The flow path 5 is also configured to communicate with an external portion of the housing 2 of the pump 1 via the inlet 3 and the outlet 4. In this configuration, a cooling element (e.g., a heat sink or a cooler) that lowers the temperature of the fluid flowing through the flow path 5 is provided in the external portion of the housing 2 of the pump 1. As a result, the fluid that has received heat from the heat-generating element 200 in the heat absorption unit 101 and whose temperature has increased is discharged from the outlet 4 to the outside of the housing 2 of the pump 1, where its temperature is lowered by the cooling element. The cooled fluid is then introduced back into the heat absorption unit 101 via the inlet 3 and the housing 2 of the pump 1, where it is used again for heat absorption.

[0112] Fig. 14 is a diagram showing a schematic configuration of a second example of a liquid-cooled heat sink 100B according to an embodiment. As shown in Fig. 14, the liquid-cooled heat sink 100B of the second example further includes a heat dissipation part 102 in addition to the heat absorption part 101 of the first example. The heat dissipation part 102 is an element that cools the fluid after absorbing heat generated from the heat-generating element 200. The heat dissipation part 102 is made of a material with high thermal conductivity, such as copper or aluminum, so as to improve the heat dissipation capacity from the fluid.

[0113] Heat dissipation unit 102 is disposed on the opposite side of housing 2 of pump 1 from heat absorption unit 101. Since housing 2 of pump 1 according to this embodiment has a substantially rectangular parallelepiped shape as described above, in the example of Fig. 14 , heat dissipation unit 102 also has a substantially rectangular parallelepiped shape similar to housing 2. Furthermore, in this embodiment, heat dissipation unit 102 is fixed to the positive Z direction side of housing 2 of pump 1, and is formed integrally with housing 2 together with heat absorption unit 101.

[0114] 14, the flow path 5 further includes a second extension flow path 5C in addition to the internal flow path 5A and extension flow path 5B of the first example. The second extension flow path 5C is a portion of the flow path 5 that is disposed inside the heat dissipation section 102. The second extension flow path 5C is provided by extending from the internal flow path 5A. The upstream end of the second extension flow path 5C is connected to the internal flow path 5A, and fluid flows in from the internal flow path 5A on the downstream side. The downstream end of the extension flow path 5B is connected to the internal flow path 5A, and fluid flows out to the internal flow path 5A on the upstream side.

[0115] 14, the internal flow path 5A is not connected to the inlet 3 or the outlet 4, but connects the extension flow path 5B of the heat absorption unit 101 and the second extension flow path 5C of the heat radiation unit 102, and circulates the fluid in the flow path 5. The internal flow path 5A has one internal flow path that connects the upstream end of the extension flow path 5B to the downstream end of the second extension flow path 5C, and the other internal flow path that connects the downstream end of the extension flow path 5B to the upstream end of the second extension flow path 5C. That is, in the second example of FIG. 14, the flow path 5 is configured so that it passes through one of the internal flow paths 5A, then passes through the inside of the heat absorption unit 101 via the extension flow path 5B, then passes through the other of the internal flow paths 5A, then passes through the inside of the heat radiation unit 102 via the second extension flow path 5C, and then connects again to one of the internal flow paths 5A.

[0116] 14, the second example of the liquid-cooled heat sink 100B can cool the fluid by dissipating heat generated in and received by the heat-generating element 200 to the outside from the fluid flowing through the second extension flow path 5C of the heat dissipation unit 102. Also, as in the first example, the heat-generating element 200 can be cooled by the heat absorption from the heat-generating element 200 by the fluid flowing through the extension flow path 5B of the heat absorption unit 101.

[0117] 14, a second example may be configured to further include a cooling body 300 to improve the heat dissipation capacity of the heat dissipation unit 102. The cooling body 300 is disposed on the opposite side of the heat dissipation unit 102 from the housing 2 of the pump 1. For example, if the cooling body 300 is a heat pipe or a heat dissipation pad, the cooling body 300 also has a main surface 300A facing the negative Z direction, and the other main surface 102B of the pair of main surfaces of the heat dissipation unit 102 facing the positive Z direction can be in surface contact with the main surface 300A of the cooling body 300. In this embodiment, as shown in FIG. 14, the cooling body 300 also has a main surface 300A facing the negative Z direction, and the other main surface 102B of the pair of main surfaces of the heat dissipation unit 102 facing the positive Z direction is in surface contact with the main surface 300A of the cooling body 300. This increases the contact area between heat dissipation unit 102 and cooling body 300, improving heat dissipation efficiency and increasing the effect of reducing the temperature of the fluid. Furthermore, for example, if cooling body 300 is a fan, main surface 300A of cooling body 300 does not necessarily have to be in surface contact with main surface 102B of heat dissipation unit 102.

[0118] Fig. 15 is a diagram showing a schematic configuration of a third example of a liquid-cooled heat sink 100C according to an embodiment. As shown in Fig. 15, the liquid-cooled heat sink 100C of the third example does not include the heat absorption part 101 shown in Figs. 13 and 14 or the heat dissipation part 102 shown in Fig. 14, and is configured so that the housing 2 of the pump 1 is in direct contact with the heat-generating element 200. In other words, in the third example, the housing 2 of the pump 1 itself functions as a heat sink.

[0119] Furthermore, similar to the first example, in the third example, the heating element 200 has a main surface 200A facing the positive Z direction, and is in surface contact with a main surface 22 facing the negative Z direction of the housing 2 of the pump 1. This increases the contact area between the housing 2 and the heating element 200, thereby improving the heat absorption efficiency.

[0120] In the third example of FIG. 15, the flow path 5 has only an internal flow path 5A disposed inside the housing 2 of the pump 1. The fluid flowing through the internal flow path 5A absorbs heat from the heating element 200, thereby cooling the heating element 200. As in the first example of FIG. 13, the fluid that has received heat from the heating element 200 in the internal flow path 5A and whose temperature has increased is discharged from the outlet 4 to the outside of the housing 2 of the pump 1, where its temperature is lowered by a cooling element. The cooled fluid is then introduced again from the inlet 3 into the internal flow path 5A within the housing 2 of the pump 1, where it is used again to absorb heat.

[0121] As described above, the liquid-cooled heat sinks 100A, 100B, and 100C according to the present embodiment are devices that cool the heat-generating element 200 by absorbing heat from the heat-generating element 200 using a fluid flowing through the flow path 5, and include the pump 1 according to the present embodiment described with reference to FIGS. 1 to 12 as an element for pumping the fluid through the flow path 5. As described above, the pump 1 according to the present embodiment is configured to use the resonant actuator 6 as a drive source, and therefore the movable parts (first movable plate 62, second movable plate 63, first leaf spring 64, and second leaf spring 65) of the resonant actuator 6 can be vibrated efficiently by utilizing the resonance of the movable parts. This increases the efficiency of the pump 1, and by using the pump 1 as a fluid-discharge element, the fluid can be moved efficiently, resulting in improved cooling performance of the liquid-cooled heat sinks 100A, 100B, and 100C to which the pump 1 is applied.

[0122] The present embodiment has been described above with reference to specific examples. However, the present disclosure is not limited to these specific examples. Design modifications to these specific examples made by a person skilled in the art as appropriate are also included within the scope of the present disclosure as long as they comprise the features of the present disclosure. The elements of the above-described specific examples, as well as their arrangement, conditions, shape, etc., are not limited to those exemplified and can be modified as appropriate. The elements of the above-described specific examples can be combined in various ways as appropriate, as long as no technical contradictions arise.

[0123] The pump 1 according to the embodiment may have a structure other than that described above as long as it is capable of at least pumping out the fluid in the flow path 5. For example, the above embodiment illustrates a configuration in which the intake port 3 is disposed on the side surface 23 of the housing 2 and the exhaust port 4 is disposed on the side surface 24, but the locations of the intake port 3 and the exhaust port 4 may be changed as desired.

[0124] Furthermore, in the above embodiment, a configuration in which the first pump chamber 7 and the second pump chamber 8 are both arranged on the axis of symmetry CA is exemplified, but the arrangement of the first pump chamber 7 and the second pump chamber 8 only needs to be at least the fourth flow path 54 and the fifth flow path 55, and they may also be at a position other than the axis of symmetry CA.

[0125] In addition, in the above embodiment, a configuration in which two pistons, a first piston 71, 81 and a second piston 72, 82, are arranged in each pump chamber 7, 8 is exemplified, but a configuration in which only a single piston is installed in one pump chamber may also be used.

[0126] Furthermore, in the above embodiment, the configuration in which two pump chambers 7 and 8 are provided in the flow path 5 is exemplified, but the configuration in which only a single pump chamber is provided in the flow path 5 may also be used.

[0127] In addition, in the above embodiment, a configuration was exemplified in which two movable parts, a first movable part (first movable plate 62 and first leaf spring 64) and a second movable part (second movable plate 63 and second leaf spring 65), are provided on either side of a single fixed part including an electromagnet 61, but a configuration in which only one of the pair of movable parts is provided may also be used.

[0128] In the above embodiment, a configuration using the first pistons 71, 81 and the second pistons 72, 82 was exemplified as an example of a volume change member that operates to reduce the volume of the pump chambers 7, 8 in response to the attraction of the movable plates 62, 63 toward the electromagnet 61, and that operates to increase the volume of the pump chambers 7, 8 in response to the separation of the movable plates 62, 63 from the electromagnet 61 due to the biasing forces f1, f2 of the leaf springs 64, 65 when the electromagnet 61 is switched off after the attraction, but elements other than pistons may also be used. Examples of elements other than pistons that can be used as volume change members include a diaphragm and a bellows. [Explanation of symbols]

[0129] 1 pump 5 Flow path 6 Resonant Actuators 61 Electromagnet (fixed part) 611 cores 611A Winding section 611B Pair of widened sections 612 Coil 62 First movable plate (movable part) 63 Second moving plate (moving part) 64 First leaf spring (moving part) 641 Central part 642 Pair of fixed ends 643 Flexure 65 Second leaf spring (moving part) 651 Central part 652 Pair of fixed ends 653 Flexure 7. First Pump Room 71 First piston (volume change member) 72 Second piston (volume change member) 74 Intake valve 75 Discharge valve 8. Second Pump Room 81 First piston (volume change member) 82 Second piston (volume change member) 9 Support 100A, 100B, 100C Liquid Cooled Heatsink 101 Heat absorption part 102 Heat radiation part 5A Internal flow path 5B Extension channel 5C 2nd extension channel 200 Heating element 300 Cooling body W1 Width dimension of leaf spring W2 Width dimension of the movable plate

Claims

1. A liquid-cooled heat sink that cools a heat-generating body by absorbing heat from the heat-generating body with a fluid flowing through a flow path, a pump for pumping the fluid in the flow path; The pump An electromagnet and a movable plate that is attracted to the electromagnet by a magnetic field generated by energizing the electromagnet; a leaf spring to which the movable plate is attached, the leaf spring biasing the movable plate in a direction opposite to the attraction of the movable plate to the electromagnet in response to the attraction of the movable plate to the electromagnet; a pump chamber provided on the flow path; a volume change member that operates to reduce the volume of the pump chamber in response to the suction action of the movable plate, and that operates to increase the volume of the pump chamber in response to a separating action of the movable plate from the electromagnet caused by the biasing force of the leaf spring when the electromagnet is switched to a non-energized state after the suction action; an intake valve provided in the pump chamber on the upstream side of the flow path, the intake valve opening when the volume change member operates in a direction to increase the volume of the pump chamber to draw the fluid from the upstream side of the flow path into the pump chamber; a discharge valve provided in the pump chamber downstream of the flow path, the discharge valve opening when the volume change member operates in a direction to reduce the volume of the pump chamber to discharge the fluid from the pump chamber downstream of the flow path; having Liquid cooled heat sink.

2. the pump has a housing that houses the movable plate, the leaf spring, the pump chamber, the volume changing member, the suction valve, and the discharge valve, a heat absorbing portion disposed between the housing and the heat generating element; an extension flow path disposed inside the heat absorption portion and extending from the flow path built into the housing of the pump; Equipped with The heat-generating body is cooled by the fluid flowing through the extension flow path of the heat-absorbing portion absorbing heat from the heat-generating body. The liquid-cooled heat sink of claim 1 .

3. a heat dissipation unit disposed on the opposite side of the housing from the heat absorption unit; a second extension flow path disposed inside the heat dissipation unit and extending from the flow path built into the housing of the pump; Equipped with The heat generated by the heat generating element and received by the fluid flowing through the second extension flow path of the heat dissipation unit is released to the outside, thereby cooling the fluid. The liquid-cooled heat sink according to claim 2 .

4. a cooling body disposed on the opposite side of the housing with the heat dissipation unit interposed therebetween, The cooling body absorbs heat generated by the heating element and received from the fluid flowing through the second extension flow path of the heat dissipation section, thereby cooling the fluid.

4. The liquid-cooled heat sink according to claim 3.

5. the volume-changing member of the pump is a piston installed on the movable plate, the piston is movable in the direction of the suction operation of the movable plate and the direction of the separation operation of the movable plate. The liquid-cooled heat sink of claim 1 .

6. the movable plate of the pump includes a first movable plate and a second movable plate disposed opposite to each other with the electromagnet interposed therebetween, the leaf spring of the pump includes a first leaf spring and a second leaf spring to which the first movable plate and the second movable plate are respectively attached; the volume change member of the pump includes a first volume change member and a second volume change member that are linked to the movements of the first movable plate and the second movable plate, The liquid-cooled heat sink of claim 1 .

Images