Electromagnetic coil unit

Abstract

Provided is an electromagnetic coil unit capable of improving heat dissipation performance. The axis (A1) of the winding (41) is disposed so as to be offset in the X direction from the center of the intersecting plate section (51), whereby a temperature difference can be generated on both sides in the X direction across the axis (A1) in the space inside the outer case (5) and around the coil section (4), and an airflow in the X direction can be generated by the temperature difference. The dimension of the coil part (4) in the Y direction is 64-87% of the interval between the pair of connecting plate parts (53, 54), so that the air flow can efficiently pass through the space between the coil part (4) and the connecting plate parts (53, 54), and the heat dissipation performance can be improved.

Description

Technical Field

[0001] The present invention relates to a solenoid coil unit for a solenoid valve. Background Art

[0002] Generally, there is known a solenoid valve that excites a fixed iron core arranged inside the winding by energizing the winding, and switches the flow path by moving the movable iron core. As such a solenoid valve, a solenoid valve having a frame that holds a solenoid coil as a winding and forms a magnetic path is proposed (for example, refer to Patent Document 1). In the solenoid valve described in Patent Document 1, the frame has an end plate portion that abuts against one end portion of the hollow winding tube in the direction of the central axis, a pair of side plates combined with the end plate portion, and extensions extending from the side plates toward the central axis to form a single component. As a result, improvement in magnetic flux loss is achieved relative to the frame having a C-shaped cross-section.

[0003] Prior art literature

[0004] Patent Literature

[0005] Patent Document 1: Japanese Patent Application Laid-Open No. 2005-113991 Summary of the Invention

[0006] Problems to be solved by the invention

[0007] In the solenoid valve described in Patent Document 1, although it is possible to reduce magnetic flux loss by forming a magnetic circuit by surrounding the winding with a quadrilateral cylindrical frame, there is a disadvantage in that it is difficult to dissipate the heat generated when the winding is energized to the outside of the frame. For example, when the cross-sectional area or number of turns of the wire constituting the winding is reduced to reduce the amount of wire used in order to reduce costs, the resistance value increases, or the current required to ensure the magnetomotive force increases. The resistance loss, which is the main cause of heat generation, increases depending on both the current and the resistance value. Therefore, when the amount of wire used is reduced as described above, heat is easily generated. Therefore, it is desired to improve the heat dissipation performance in the electromagnetic coil unit used for the electromagnetic drive valve.

[0008] An object of the present invention is to provide an electromagnetic coil unit capable of improving heat dissipation performance.

[0009] Solutions to Problems

[0010] The electromagnetic coil unit of the present application is provided with a coil portion and an outer case arranged outside the coil portion, and is used for switching a flow path in a solenoid valve. The electromagnetic coil unit is characterized in that the coil portion has a winding formed in a spiral shape around a prescribed axis, the outer case has a pair of intersecting plate portions sandwiching the coil portion from the direction of the axis and a pair of linking plate portions linking the pair of intersecting plate portions to each other, and is formed in a quadrangular tube shape with a direction orthogonal to both the direction opposite to each other of the pair of intersecting plate portions and the direction opposite to each other of the pair of linking plate portions as an extending direction, the axis is arranged offset from the central portion of the intersecting plate portion in the extending direction, and the size of the coil portion in the direction opposite to each other of the pair of linking plate portions is 64 to 87% of the interval between the pair of intersecting plate portions.

[0011] According to the present application as described above, the axis of the winding is arranged offset from the central portion of the intersecting plate portion, thereby forming a portion close to the outside space and a portion away from the outside space on the winding in the extending direction of the outer case. Since the portion of the winding close to the outside space is more easily cooled, a temperature difference is generated on both sides across the axis in the space inside the outer case and around the coil portion. A pressure difference is generated by the temperature difference, thereby generating an air flow from the high-pressure side (low-temperature side) toward the low-pressure side (high-temperature side) (in other words, a density difference is generated by the temperature difference, thereby generating an air flow from the high-density side (low-temperature side) toward the low-density side (high-temperature side)). As described above, the size of the coil portion in the direction opposite to each other of the pair of linking plate portions, which is orthogonal to the direction (extending direction) in which the air flow is generated, is 64 to 87% of the interval between the pair of intersecting plate portions, whereby the air flow can efficiently pass through between the coil portion and the linking plate portion, and the heat dissipation performance can be improved.

[0012] On the contrary, if the size of the coil portion is too large with respect to the interval between the pair of linking plate portions, the gap between the coil portion and the linking plate portion becomes small, and the air flow is difficult to pass through, making it difficult to obtain sufficient heat dissipation performance. Further, if the size of the coil portion is too small with respect to the interval between the pair of linking plate portions, it is difficult to generate the temperature difference and the pressure difference as described above, thereby making it difficult to generate the air flow, and the magnetic path of the outer case as a magnetic yoke becomes long, resulting in a decrease in magnetic efficiency.

[0013] At this time, in the electromagnetic coil unit of the present application, it is preferable that the extending direction of the outer case be along the vertical direction, and the axis be arranged on the lower side with respect to the central portion. According to such a structure, in addition to the air flow generated by the temperature difference, the air flow can pass through between the coil portion and the linking plate portion as an upward air flow, and the heat dissipation performance can be further improved.

[0014] In addition, in the electromagnetic coil unit of the present invention, it is preferred that the offset of the axis from the central portion is 2% to 10% of the size of the cross plate portion in the extension direction. According to such a structure, it is easy to generate the above-mentioned airflow while suppressing the size. Moreover, the offset is more preferably 3% to 8% of the size of the cross plate portion in the extension direction. According to such a structure, it is easy to generate the above-mentioned airflow while further suppressing the size. In contrast, if the offset is too large relative to the above-mentioned size of the cross plate portion, the electromagnetic coil unit is likely to be large-scale. In addition, if the offset is too small relative to the above-mentioned size of the cross plate portion, it is difficult to generate a temperature difference and it is difficult to generate an airflow.

[0015] Effects of the Invention

[0016] According to the electromagnetic coil unit of the present invention, heat dissipation performance can be improved. BRIEF DESCRIPTION OF THE DRAWINGS

[0017] Figure 1 It is a schematic configuration diagram of a refrigeration cycle provided with a solenoid valve according to an embodiment as an example of the present invention.

[0018] Figure 2 It is a cross-sectional view showing the above-mentioned solenoid valve.

[0019] Figure 3 It is a top view showing the above-mentioned solenoid valve. DETAILED DESCRIPTION

[0020] The embodiment of the present invention will be described with reference to the accompanying drawings. The electromagnetic coil unit 1 of this embodiment is used for Figure 1 The solenoid valve 102 shown in FIG. 1 is configured as follows. Figure 1 Refrigeration cycle 100 is shown. Refrigeration cycle 100 is used in air conditioners such as room air conditioners, package air conditioners, and multi-split air conditioners. It includes a compressor 103 that compresses a refrigerant (a fluid); an outdoor heat exchanger 104 that functions as a first heat exchanger and a condenser in cooling mode; an indoor heat exchanger 105 that functions as a second heat exchanger and an evaporator in cooling mode; an expansion valve 106 that expands and decompresses the refrigerant between outdoor and indoor heat exchangers 104 and 105; a four-way switching valve 101; and a solenoid valve 102, a pilot solenoid valve that controls the flow path of four-way switching valve 101. These components are connected by refrigerant piping. The expansion unit is not limited to expansion valve 106; a capillary tube may also be used.

[0021] The refrigeration cycle 100 Figure 1In the cooling mode (cooling operation) indicated by the solid arrows, a refrigeration cycle is formed in which the refrigerant flows in the order of compressor 103, four-way switching valve 101, outdoor heat exchanger 104, expansion valve 106, indoor heat exchanger 105, four-way switching valve 101, and compressor 103. On the other hand, in the heating mode (heating operation) indicated by the dotted arrows, a heating cycle is formed in which the refrigerant flows in the order of compressor 103, four-way switching valve 101, indoor heat exchanger 105, expansion valve 106, outdoor heat exchanger 104, four-way switching valve 101, and compressor 103. Switching between the heating cycle and the refrigeration cycle is performed by switching the four-way switching valve 101 by the solenoid valve 102.

[0022] The four-way switching valve 101 is a well-known four-way switching valve, comprising a cylindrical valve body 111, a sliding valve 112 slidably disposed within the valve body, a high-pressure conduit (D-connector) 113 communicating with the discharge port of the compressor 103, a low-pressure conduit (S-connector) 114 communicating with the suction port of the compressor 103, an indoor conduit (E-connector) 115 communicating with the indoor heat exchanger 105, and an outdoor conduit (C-connector) 116 communicating with the outdoor heat exchanger 104. The valve body 111 is formed as a completely sealed cylinder by having plugs 117 and 118 that close its axial ends. Spaces A11 and A12 are formed to axially sandwich a piston 119 that moves the sliding valve 112.

[0023] The solenoid valve 102 of this embodiment is a well-known solenoid valve having a four-way switching valve structure, and includes a valve body 120, a valve seat portion 121, a valve core 122, an electromagnetic coil unit 1, and joint components 123 to 126. The flow path of the fluid is switched by moving the valve core 122 along a predetermined sliding direction (i.e., a moving direction). In addition, Figure 1 The diagram schematically shows how the components constituting the refrigeration cycle 100 are connected, and does not show the positional relationship, orientation, size, etc. of the components. In particular, the detailed structure, arrangement, and orientation of the electromagnetically driven valve 102 are described below.

[0024] The electromagnetic coil unit 1 is also Figure 2 、 Figure 3 As shown, the solenoid valve 102 includes a plunger 2, an attractor 3, a coil unit 4, and an outer case 5. By energizing the winding 41 of the coil unit 4, the attractor 3 is excited, causing the plunger 2 to move toward the attractor 3. This in turn causes the valve element 122, which is held by the plunger 2, to move. By switching the flow path in the solenoid valve 102, the high-pressure fluid in the high-pressure conduit 113 is directed to one of the spaces A11 and A12 axially sandwiching the piston 119, while the low-pressure fluid in the low-pressure conduit 114 is directed to the other space, causing the piston 119 to move toward the low-pressure space.

[0025] The coil unit 4 comprises a winding 41, a molded portion 42, and a bobbin 43, and is integrally formed by molding. The winding 41 is a solenoid coil in which a conductive wire 411 is helically wound about the bobbin 43, centered about a predetermined axis A1. The molded portion 42 is formed from a molded resin serving as an insulator, with the winding 41 positioned inside.

[0026] Hereinafter, the direction of the axis A1 is referred to as the Z direction, and the plane perpendicular to the Z direction is referred to as the XY plane.

[0027] The coil portion 4 has end faces 44 and 45 on both sides of the Z direction, a portion of a cylinder centered on the axis A1, namely a curved portion 46, and a protrusion 47 protruding from the curved portion 46 to one side of the X direction (the upper side of the vertical direction). The curved portion 46 and the winding 41 are formed concentrically, and the protrusion 47 is a portion provided to connect the lead 6 to the winding 41. In this way, the outer peripheral shape of the coil portion 4 becomes an asymmetric shape on both sides of the surface passing through the axis A1 and along the YZ plane. The protrusion 47 has a pair of flat portions 471 that are continuous with the curved portion 46 and extend toward one side of the X direction. The flat portion 471 is inclined relative to the ZX plane.

[0028] The outer box 5 has a pair of cross plate portions 51, 52 and a pair of connecting plate portions 53, 54 connecting the pair of cross plate portions 51, 52 to each other. The cross plate portion 51 is configured to extend along the XY plane and to contact the end face 44 of the coil portion 4 from the side opposite to the valve seat portion 121. A through hole 511 for fixing the attractor 3 is formed in the cross plate portion 51. The center of the through hole 511 coincides with the center of the cylindrical attractor 3, and the attractor 3 and the winding 41 are arranged concentrically. Therefore, the center of the through hole 511 coincides with the center of the winding 41 (i.e., the axis A1).

[0029] The through hole 511 is arranged to be offset from the center of the cross plate portion 51 toward the lower side in the vertical direction in the X direction. Figure 3 In the figure, a dashed line indicates line LN1, which passes through the center of the intersecting plate portion 51 in the X direction and extends along the Y direction. The through-hole 511 and the axis A1 are located below line LN1. Therefore, in the solenoid valve 102, the axis A1 of the winding 41 is offset downward from the center of the intersecting plate portion 51 in the X direction. The offset ΔX of the axis A1 from line LN1 is 2% to 10%, more preferably 3% to 8%, of the X-direction dimension LX of the intersecting plate portion 51.

[0030] A notch 512 for arranging the lead 6 is formed at the upper end edge in the X direction of the intersecting plate portion 51. That is, the axis A1 is offset to the side opposite to the side where the notch 512 is formed.

[0031] The cross plate portion 52 is configured to extend along the XY plane and to contact the end face 45 of the coil portion 4 from the valve seat portion 121 side. A through hole 521 is formed on the cross plate portion 52, through which the valve body 120 is inserted. In addition, the portions on both sides of the Y direction of the cross plate portion 52 separated by the through hole 521 may be connected to each other or may be independent of each other (i.e., as in the above-mentioned patent document 1, for example, the outer box 5 is formed by bending a metal plate, and a slit is formed at the joint between the end edges of the metal plates). In addition, the X-direction dimensions and Y-direction dimensions of the cross plate portion 51 and the cross plate portion 52 are equal to each other.

[0032] The connecting plate portions 53 and 54 connect the Y-direction end portions of the pair of intersecting plate portions 51 and 52 to each other and extend along the ZX plane.

[0033] As described above, the outer box 5 is formed into an extended quadrilateral cylindrical shape by the pair of cross plate portions 51 and 52 and the pair of connecting plate portions 53 and 54 , and the extending direction thereof coincides with the X direction.

[0034] The outer box 5 forms a magnetic circuit and functions as a yoke. That is, the magnetic flux passes from one end of the winding 41 to the other end through the cross plate 51, passes through the pair of connecting plates 53 and 54, and returns to the coil unit 4 through the cross plate 52 (or the magnetic flux passes in the opposite direction).

[0035] The following describes the relationship between the coil unit 4 and the outer box 5, as well as the heat dissipation method. First, a gap is formed between the outer peripheral surface of the coil unit 4 (particularly the curved surface portion 46) and the connecting plate portions 53 and 54. In this case, the Y-direction dimension L1 of the coil unit 4 is 64-87% of the spacing L2 between the pair of connecting plate portions 53 and 54 (i.e., the spacing between the inner surfaces). Note that the Y-direction dimension L1 of the coil unit 4 refers to the maximum dimension in the Y direction.

[0036] In addition, as described above, the axis A1 is offset downward relative to the line LN1, so the coil portion 4 is located near the lower opening in the cylindrical outer box 5. As a result, when the coil portion 4 generates heat due to power, the lower side in the X direction is more easily cooled by the outside air than the upper side. That is, in the space inside the outer box 5 and around the coil portion 4, the temperature of the upper side is higher than that of the lower side compared to the axis A1. The pressure in the high-temperature area is relatively lower than that in the low-temperature area, and this pressure difference generates an airflow from the low-temperature side toward the high-temperature side (from the lower side to the upper side) (in other words, the density difference generated by the above-mentioned temperature difference generates an airflow from the high-density side (low-temperature side) toward the low-density side (high-temperature side)).

[0037] At this time, a gap is formed between the outer peripheral surface of the coil portion 4 and the connecting plate portions 53 , 54 , so that the above-mentioned airflow can pass between the coil portion 4 and the connecting plate portions 53 , 54 .

[0038] According to the above embodiment, by arranging the axis A1 of the winding 41 offset from the center of the cross plate portion 51 in the X direction, a temperature difference is generated on either side of the axis A1 in the X direction within the outer box 5 and in the space surrounding the coil portion 4. This temperature difference generates an X-directional airflow. By setting the Y-direction dimension of the coil portion 4 to 64% to 87% of the spacing between the pair of connecting plates 53 and 54, this airflow can efficiently pass between the coil portion 4 and the connecting plates 53 and 54, thereby improving heat dissipation performance.

[0039] In contrast, if the Y-direction dimension of the coil portion 4 is too large relative to the spacing between the pair of connecting plate portions 53 and 54, it becomes difficult to ensure a gap between them, making it difficult for airflow to pass through and achieving sufficient heat dissipation performance. Furthermore, if the Y-direction dimension of the coil portion 4 is too small relative to the spacing between the pair of connecting plate portions 53 and 54, it becomes difficult to generate the aforementioned temperature difference and airflow, and the magnetic path of the outer box 5, which serves as the magnetic yoke, becomes longer, resulting in a decrease in magnetic efficiency.

[0040] In addition, by extending the quadrilateral cylindrical outer box 5 in the vertical direction and arranging the axis A1 of the winding 41 at the lower side relative to the center of the cross plate portion 51, the rising airflow can pass between the coil portion 4 and the connecting plate portions 53 and 54, thereby further improving the heat dissipation performance.

[0041] Furthermore, by setting the offset ΔX of the axis A1 of the winding 41 from the center of the intersecting plate portion 51 to 2% to 10%, more preferably 3% to 8%, of the X-direction dimension LX of the intersecting plate portion 51, it is easier to generate the aforementioned airflow while suppressing size increase. In contrast, if the offset ΔX is too large relative to the dimension LX, the electromagnetic coil unit tends to increase in size. Furthermore, if the offset ΔX is too small relative to the dimension LX, it becomes difficult to generate a temperature difference, making it difficult to generate airflow.

[0042] It should be noted that the present invention is not limited to the above-described embodiment and includes other structures that can achieve the objectives of the present invention. The following variations are also included in the present invention. In the above-described embodiment, the quadrilateral cylindrical outer box 5 extends in the vertical direction. However, the direction of extension of the outer box can also be slightly inclined relative to the vertical direction. In addition, in the case where airflow is easily generated due to the temperature difference described above, the direction of extension of the outer box can also be along a single direction within the horizontal plane.

[0043] Furthermore, in the above embodiment, the offset ΔX of the axis A1 of the winding 41 from the center of the intersecting plate portion 51 is 2% to 10%, more preferably 3% to 8%, of the X-direction dimension LX of the intersecting plate portion 51. However, the offset is not limited to this range. For example, if the outer box is sufficiently large relative to the winding, the offset can be increased to facilitate temperature differences. Alternatively, if temperature differences are likely to occur, the offset can be reduced.

[0044] While the embodiments of the present invention have been described in detail with reference to the drawings, the specific configuration is not limited to these embodiments, and design changes and the like within the scope not departing from the gist of the present invention are also encompassed by the present invention.

[0045] [Example]

[0046] In the electromagnetic coil unit 1 of the above-described embodiment, the ratio of the Y-direction dimension L1 of the coil portion 4 to the interval L2 between the pair of connecting plate portions 53 and 54 was changed, and the temperature was measured to confirm the relative temperature increase (temperature increase ratio).

[0047] As common experimental conditions, the applied voltage was set to 240V and 50Hz, and the temperature was measured at the point where the power was continuously applied and the temperature reached saturation. The power consumption during power application was also measured. By maintaining the dimensions of the outer box 5 and only changing the Y-direction dimension L1 of the coil portion 4, the ratio of these dimensions L1 to L2 was varied. The measurement results of the ratio of dimensions L1 to L2, the temperature rise ratio, and the power consumption are shown in Table 1.

[0048] [Table 1]

[0049] Size ratio (L1 / L2) Temperature rise rate (%) Power consumption ratio (%) Comparative Example 1 91 100 100 Example 1 85 94 100 Example 2 80 95 100 Example 3 71 95 102 Example 4 64 95 101 Comparative Example 2 58 99 101

[0050] The temperature rise ratio was calculated by dividing the temperature rise value in each Example and Comparative Example by the temperature rise value in Comparative Example 1. Similarly, the power consumption ratio was calculated by dividing the power consumption value in each Example and Comparative Example by the power consumption value in Comparative Example 1. In Examples 1 to 4, where the L1 to L2 ratio was 64% to 85%, the temperature rise ratio was low. Even after considering the power consumption ratio, it was confirmed that the temperature rise ratio was low in Examples 1 to 4.

[0051] Explanation of symbols

[0052] 1…Solenoid coil unit, 4…Coil section, 41…Winding, 5…External case, 51, 52…Cross plate section, 53, 54…Connecting plate section, 102…Solenoid valve, A1…Axis

Claims

1. An electromagnetic coil unit comprising a coil portion and an outer box disposed outside the coil portion, for switching a flow path in a solenoid valve. The electromagnetic coil unit is characterized in that: The coil portion has a winding formed in a spiral shape around a predetermined axis. The outer box includes a pair of cross plate portions that sandwich the coil portion from the direction of the axis and a pair of connecting plate portions that connect the pair of cross plate portions to each other, and is formed into a quadrilateral cylindrical shape with directions perpendicular to both the opposing directions of the pair of cross plate portions and the opposing directions of the pair of connecting plate portions as extending directions. The axis is arranged to be offset from the center of the cross plate portion in the extending direction. In the opposing direction of the pair of connecting plate portions, a dimension of the coil portion is 64% to 87% of a distance between the pair of intersecting plate portions.

2. The electromagnetic coil unit according to claim 1, wherein The electromagnetic coil unit is arranged in the electromagnetic valve such that the extending direction of the outer box is along the vertical direction and the axis is arranged below the central portion.

3. The electromagnetic coil unit according to claim 1, wherein The offset amount of the axis from the central portion is 2% to 10% of the dimension of the intersecting plate portion in the extending direction.

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