Equipment Unit

Abstract

To provide an apparatus unit which can prevent noise caused by resonance of air columns from being emitted to surroundings, when two apparatuses are arranged with a gap.SOLUTION: An apparatus unit comprises: a vibrating first apparatus 3; a second apparatus 4 arranged with a gap 5 from the first apparatus 3; and a projecting part 25 which is arranged in an outer periphery of the gap 5, and formed so as to narrow the gap 5. In a state that the projecting part 25 is not prepared, a direction in which a free-traveling sound wave caused by resonance of air columns generated in the gap 5 is propagated is considered to be propagation directions D1, D2. In the state that the projecting part 25 is not prepared, an area when projecting the gap 5 in the propagation directions D1, D2 is considered to be an opening area. The area when projecting the projecting area 25 in the propagation directions D1, D2 is considered to be a projecting area. Then, the projecting area is 15% or more of the opening area.SELECTED DRAWING: Figure 6

Description

[Technical field]

[0001] The present disclosure relates to an equipment unit. [Background technology]

[0002] Conventionally, various efforts have been made to reduce noise in devices mounted on vehicles. For example, an intake manifold disclosed in JP 2015-197080 A includes a surge tank, a branch pipe, and two partition walls.

[0003] The two partition walls are formed to connect the outer wall of the surge tank and the outer wall of the branch pipe, and are formed to separate a space surrounded by the engine, the surge tank, and the branch pipe when the intake manifold is assembled to the engine. One of the partition walls has a large number of through holes, while the other partition wall has no through holes.

[0004] By forming the two partition walls as described above, noise generated in the intake manifold is reduced. [Prior art documents] [Patent documents]

[0005] [Patent Document 1] JP 2015-197080 A Summary of the Invention [Problem to be solved by the invention]

[0006] The electric vehicle includes a transaxle, a power control unit (PCU), and a boost converter. The transaxle includes a housing case, and a rotating electric machine and a transmission housed in the housing case.

[0007] The PCU is fixed to the upper surface of the transaxle case, for example. The boost converter is disposed above the PCU with a gap therebetween.

[0008] The transaxle includes a housing case and a rotating electric machine and a transmission housed in the housing case. When the rotating electric machine and the transmission are driven, they vibrate. When the vibration is transmitted to the housing case, the PCU vibrates.

[0009] When the PCU vibrates, air column resonance occurs in the gap between the PCU and the boost converter, which can cause noise to be radiated to the surroundings.

[0010] In this way, when two devices are placed with a gap between them, air column resonance may occur in the gap, causing sound to be radiated to the surroundings.

[0011] The present disclosure has been made in consideration of the above-mentioned problems, and has an objective to provide an equipment unit that can suppress radiation of noise caused by air column resonance to the surroundings when two pieces of equipment are arranged with a gap between them. [Means for solving the problem]

[0012] The equipment unit of the present disclosure is an equipment unit comprising a vibrating first device, a second device arranged with a gap from the first device, and a protrusion arranged on the outer periphery of the gap and formed to narrow the gap, in which, when the protrusion is not provided, the direction in which the traveling sound wave of the air column resonance generated in the gap propagates is taken as the propagation direction, and when the protrusion is not provided, the area of ​​the gap projected in the propagation direction is taken as the opening area, and the area of ​​the protrusion projected in the propagation direction is taken as the protruding area, the protruding area is 15% or more of the opening area.

[0013] According to the above equipment unit, when two pieces of equipment are arranged with a gap therebetween, it is possible to suppress noise caused by air column resonance from being emitted to the surroundings.

[0014] The protruding portion is formed so as to protrude from the first device toward the second device, and a gap between the protruding portion and the second device is 1.5 mm or less.

[0015] The equipment unit of the present disclosure is an equipment unit comprising a vibrating first device and a second device arranged with a gap therebetween, the distance between the first device and the second device being equal to or greater than 0.6 mm and equal to or less than 1.5 mm. Effect of the Invention

[0016] According to the equipment unit of the present disclosure, when two pieces of equipment are arranged with a gap between them, it is possible to suppress noise caused by air column resonance from being emitted to the surroundings. [Brief description of the drawings]

[0017] [Figure 1] FIG. 1 is a front view that shows a schematic diagram of an equipment unit 1 and a transaxle 2 according to a first embodiment of the present invention. [Diagram 2] FIG. [Diagram 3] 2 is a plan view showing the upper surface 23 of the PCU 3. FIG. [Figure 4] 2 is a perspective view showing a configuration of a protrusion 25 and the periphery of the protrusion 25. FIG. [Diagram 5] 2 is a plan view of the boost converter 4 and the PCU 3 as viewed from above the boost converter 4. FIG. [Figure 6] 2 is a perspective view showing a PCU 3 and a boost converter 4, and is a perspective view showing a protrusion 25 and the surrounding configuration. FIG. [Figure 7] 7 is a cross-sectional view taken along line VII-VII in FIG. 5. [Figure 8] 8 is a cross-sectional view taken along line VIII-VIII in FIG. 5. [Figure 9]FIG. 2 is a perspective view showing an equipment unit 1A according to a comparative example. [Figure 10] FIG. 11 is a perspective view showing a part of a device unit 1B according to a second embodiment. [Figure 11] FIG. 2 is a plan view showing the equipment unit 1B. [Figure 12] 12 is a cross-sectional view taken along line XII-XII in FIG. 11. [Figure 13] 11 is a cross-sectional view taken along line XIII-XIII in FIG. 10. [Figure 14] The figure shows the increase in sound volume when air column resonance occurs in equipment units in which the shape of the protrusion 25B is changed in various ways. [Figure 15] 1 is a graph showing the peak increase in volume (dB) at the air column resonance frequency P1. [Figure 16] FIG. 11 is a perspective view showing a part of a device unit 1C according to embodiment 3. [Figure 17] FIG. 1 is a plan view showing an equipment unit 1C. [Figure 18] FIG. 18 is a cross-sectional view taken along line XVIII-XVIII in FIG. [Figure 19] 19 is a cross-sectional view taken along line XIX-XIX in FIG. 17. [Figure 20] 13 is a graph showing the increase in sound volume when air column resonance occurs in equipment units in which the shape of the protrusion 25C is changed in various ways. [Figure 21] FIG. 2 is a perspective view showing a part of the equipment unit 1D. [Figure 22] 13 is a graph showing an increase in sound volume when air column resonance occurs when the distance GP1D between the housing case 20D and the housing case 15D is changed in various ways. [Diagram 23] 1 is a graph showing the peak increase in volume (dB) at the air column resonance frequency P2. [Figure 24] FIG. 11 is a perspective view showing an equipment unit 1E according to a fifth embodiment. [Diagram 25] FIG. 2 is a cross-sectional view showing an equipment unit 1E. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0018] The equipment unit according to the present embodiment will be described with reference to Fig. 1 to Fig. 25. Among the components shown in Fig. 1 to Fig. 25, the same or substantially the same components are denoted by the same reference numerals and duplicated descriptions will be omitted. (Embodiment 1) FIG. 1 is a front view that shows a schematic diagram of an equipment unit 1 and a transaxle 2 according to the first embodiment.

[0019] The equipment unit 1 includes a PCU (power control unit) (first equipment) 3 and a boost converter (second equipment) 4. The PCU 3 is fixed to an upper surface of a transaxle (fixed member) 2. The boost converter 4 is disposed above the PCU 3 with a gap therebetween. A gap 5 is formed between the boost converter 4 and the PCU 3.

[0020] The transaxle 2 includes a housing case 10, rotating electric machines 11 and 12, and a transmission 13. The housing case 10 is made of metal. The rotating electric machines 11 and 12 and the transmission 13 are housed within the housing case 10.

[0021] The PCU 3 includes a housing case 15 and an inverter 16 housed in the housing case 15. The inverter 16 includes a plurality of switching elements such as IGBTs (Insulated Gate Bipolar Transistors). The housing case 15 is made of metal.

[0022] The boost converter 4 includes a housing case 20 and a boost circuit 21 housed in the housing case 20. The boost circuit 21 also includes a plurality of switching elements such as IGBTs. The housing case 20 is made of metal.

[0023] 2 is a perspective view showing the PCU 3. The housing case 15 is formed in a substantially rectangular parallelepiped shape. The housing case 15 includes a bottom surface 22, an upper surface 23, and a peripheral surface 24. The bottom surface 22 is fixed to the transaxle 2. The peripheral surface 24 is disposed between the bottom surface 22 and the upper surface 23. The peripheral surface 24 includes long sides 26 and 27, and short sides 28 and 29.

[0024] 3 is a plan view showing the top surface 23 of the PCU 3. The top surface 23 is formed in a rectangular shape. The top surface 23 includes a pair of long sides 30, 31 and a pair of short sides 32, 33. The protrusion 25 is provided at a corner formed by the long side 30 and the short side 32.

[0025] 4 is a perspective view showing protrusion 25 and the configuration around protrusion 25. Protrusion 25 is formed in an L-shape. Protrusion 25 includes a piece 36 extending along long side 30 and a piece 37 extending by short side 32. Protrusion 25 is formed to protrude from upper surface 23, and protrusion 25 protrudes from PCU 3 toward boost converter 4. Protrusion 25 includes upper surface 35, and upper surface 35 is located above upper surface 23.

[0026] 5 is a plan view of boost converter 4 and PCU 3 as viewed from above boost converter 4. In the present embodiment 1, boost converter 4 and PCU 3 are substantially aligned in plan view.

[0027] FIG. 6 is a perspective view showing PCU 3 and boost converter 4, and is a perspective view showing protrusion 25 and the surrounding structure.

[0028] The accommodating case 20 of the boost converter 4 includes a bottom surface 40. The bottom surface 40 is formed in a substantially rectangular shape. A gap 5 is formed between the top surface 23 of the accommodating case 15 and the bottom surface 40 of the accommodating case 20.

[0029] The outer periphery of the gap 5 opens outward. An opening portion 41, an opening portion 42, an opening portion 43, and an opening portion 44 are formed on the outer periphery edge of the gap 5. The opening portion 41 is located on the long side 30 side, and the opening portion 42 is located on the long side 31 side. The opening portion 43 is located on the short side 32 side, and the opening portion 44 is located on the short side 33 side. The opening portions 41 and 42 are arranged in the first direction D1, and the opening portions 43 and 44 are arranged in the second direction D2. The protrusions 25 are formed in the opening portions 41 and 43, which are the outer periphery of the gap 5.

[0030] Here, the first direction D1 is the propagation direction of a traveling sound wave when air column resonance occurs between the opening portion 41 and the opening portion 42. The second direction D2 is the propagation direction of a traveling sound wave when air column resonance occurs between the opening portion 43 and the opening portion 44. In the present embodiment 1, the first direction D1 and the second direction D2 intersect each other so as to be perpendicular to each other.

[0031] Fig. 7 is a cross-sectional view taken along line VII-VII in Fig. 5. In other words, it is a view of the protrusion 25 and the opening 41 in the first direction D1.

[0032] Here, in a state where the protrusion 25 is not provided, the length of the opening 41 in the second direction D2 when viewed in the first direction D1 is defined as "X." In a state where the protrusion 25 is not provided, the height of the opening 41 in the up-down direction (the direction in which the PCU 3 and the boost converter 4 are separated) is defined as "H." Here, in a state where the protrusion 25 is not provided, the area of ​​the opening 41 projected in the first direction D1 is defined as the opening area S1.

[0033] The length of protrusion 25 in second direction D2 when viewed in first direction D1 is defined as "L1." The height of protrusion 25 in the height direction when viewed in first direction D1 is defined as "H1." The projected area of ​​protrusion 25 in first direction D1 is defined as projected area S10.

[0034] In the first embodiment, the "length L1" is "0.423X" and the "height H1" is "0.95H".

[0035] Fig. 8 is a cross-sectional view taken along line VIII-VIII in Fig. 5. In other words, this is a view of the opening 43 and the protrusion 25 in the second direction D2.

[0036] In a state where the protrusion 25 is not provided, the length of the opening 43 in the first direction D1 when viewed in the second direction D2 is defined as "Y". In a state where the protrusion 25 is not provided, the height of the opening 43 is defined as "H".

[0037] The area of ​​the opening 43 projected in the second direction D2 is defined as an opening area S2, and the area of ​​the protrusion 25 projected in the second direction D2 is defined as a projected area S11.

[0038] The length of the protrusion 25 in the first direction D1 when viewed in the second direction D2 is "L2". The height of the protrusion 25 in the up-down direction when viewed in the second direction D2 is "H1". Here, "length L2" is "0.437Y".

[0039] In the equipment unit 1 configured as above, when the transaxle 2 is driven, the PCU 3 may vibrate.

[0040] "Height H", "height H1", "length X", "length Y", "length L1" and "length L2" satisfy the following formula (1). 100×{(L1+L2)×H1} / {(X+Y)×H}>15(%)...(1) The above formula (1) can be transformed into the following formula (2). 100×{projected area S10+projected area S11} / {(opening area S1+opening area S2}>15(%)...(2) 8, if the vertical distance between the top surface 35 of the protrusion 25 and the bottom surface 40 of the storage case 20 is "GP1," then GP1 is 0.05H. For example, the distance GP1 is 1.5 mm or less.

[0041] In the equipment unit 1 and transaxle 2 configured as described above, the rotating electric machines 11, 12 and the transmission 13 housed in the transaxle 2 are driven, causing the housing case 10 to vibrate. The vibration of the housing case 10 is transmitted to the PCU 3, causing the housing case 15 to vibrate. The vibration of the housing case 15 may cause air column resonance in the gap 5.

[0042] Here, first, a case where air column resonance occurs in the equipment unit 1A according to the comparative example will be described. Then, the equipment unit 1A according to the comparative example will be compared with the equipment unit 1 according to the first embodiment.

[0043] 9 is a perspective view showing an equipment unit 1A according to a comparative example. The equipment unit 1A is not provided with a protrusion 25. In the configuration other than the protrusion 25, the equipment unit 1A is the same as the equipment unit 1.

[0044] The equipment unit 1A includes a PCU 3A and a boost converter 4A. The PCU 3A includes a housing case 15A, and the boost converter 4A includes a housing case 20A. A gap 5A is formed between the housing case 20A and the housing case 15A.

[0045] When air column resonance occurs in the gap 5A, mainly a first mode air column resonance and a second mode air column resonance, which will be described below, occur.

[0046] In the first mode, air column resonance occurs between the opening portion 41A and the opening portion 42A. In the first mode, the opening portion 41A and the opening portion 42A become the "belt portion" of the air column resonance. In the first direction D1, the center of the gap 5A becomes the "node portion" of the air column resonance. In this air column resonance, the propagation direction of the traveling sound wave is the first direction D1.

[0047] Here, in the equipment unit 1A, since the protrusion 25 is not provided, air column resonance occurs over the entire surface of the opening portion 41A and the entire surface of the opening portion 42A.

[0048] In the second mode, air column resonance occurs between the opening portion 43A and the opening portion 44A. In the second mode, air column resonance occurs between the opening portion 43A and the opening portion 44A. In the second mode, the opening portion 43A and the opening portion 44A become the "belly portion" of the air column resonance. In the second direction D2, the center of the gap 5A becomes the "node portion" of the air column resonance. In the second mode, the traveling direction of the traveling sound wave is the second direction D2.

[0049] Here, in the equipment unit 1A, since the protrusion 25 is not provided, air column resonance occurs over the entire surface of the opening portion 43A and the entire surface of the opening portion 44A.

[0050] Next, a case where the first mode air column resonance occurs in the equipment unit 1 according to the first embodiment will be described.

[0051] In the present embodiment 1, as shown in Fig. 6 and Fig. 7, a protrusion 25 is provided. A distance GP1 between an upper surface 35 of the protrusion 25 and a bottom surface 40 of the housing case 20 is 1.5 mm or less. Therefore, in this portion, viscous resistance becomes high, and air column resonance is unlikely to occur.

[0052] 5, the portion of opening 41 that is closer to short side 33 than protrusion 25 is defined as opening region R1. The portion of opening 42 that faces opening region R1 in first direction D1 is defined as opening region R2.

[0053] When air column resonance of the first mode occurs, air column resonance occurs between the opening region R1 and the opening region R2. At this time, the traveling direction of the traveling sound wave when air column resonance occurs is the first direction D1.

[0054] When viewed from the first direction D1, the opening area of ​​the opening region R1 is smaller (opening area S1) than the opening portion 41A shown in Fig. 9. Similarly, when viewed from the first direction D1, the opening area of ​​the opening region R2 is smaller than the opening area (opening area S2) of the opening portion 42A shown in Fig. 9.

[0055] Therefore, when air column resonance in the first mode occurs, the noise generated from the equipment unit 1 becomes smaller than the noise generated from the equipment unit 1A.

[0056] Next, the air column resonance in the second mode will be explained. 8, the distance GP1 between the top surface 35 and the bottom surface 40 of the protrusion 25 is 1.5 mm or less. Therefore, the viscous resistance in this portion is high, and air column resonance is unlikely to occur in this portion.

[0057] 5, a portion of opening portion 43 that is located closer to long side 31 than protrusion 25 is defined as opening region R3. A portion of opening portion 44 that faces opening region R3 in second direction D2 is defined as opening region R4.

[0058] When the second mode air column resonance occurs, the air column resonance occurs between the opening region R3 and the opening region R4.

[0059] When viewed from the second direction D2, the opening area of ​​the opening region R3 is smaller than the opening area of ​​the opening portion 43A shown in Fig. 9. Similarly, the opening area of ​​the opening region R4 is smaller than the opening area of ​​the opening portion 44A.

[0060] Therefore, when air column resonance of the second mode occurs, the noise generated from the equipment unit 1 is kept smaller than the noise generated from the equipment unit 1A.

[0061] The first embodiment is configured as shown in the above formulas (1) and (2). Specifically, when the protrusion 25 and the gap 5 are projected in the traveling direction (first direction D1 and second direction D2) of the traveling sound wave of the air column resonance, the projected area of ​​the protrusion 25 (projected area S10+projected area S11) is 15% of the opening area of ​​the gap 5 (opening area S1+opening area S2).

[0062] By forming the protrusion 25 in this manner, the occurrence of air column resonance within the protrusion 25 can be suppressed.

[0063] In this embodiment 1, the protrusion portion 25 is formed in an L-shape and has a shape that includes both the arm portion 36 and the arm portion 37, but the protrusion portion 25 may also be shaped so that only one of the arm portions 36 and 37 is provided.

[0064] For example, even when only the piece portion 37 is provided, the projected area S11 of the protrusion 25 is 15% or more of the opening area S2 of the opening portion 43. This makes it possible to sufficiently reduce the area where the second mode air column resonance occurs, thereby enabling noise to be effectively reduced. (Embodiment 2) The equipment unit 1B according to the second embodiment will be described with reference to Fig. 10 etc. The equipment unit 1B has substantially the same structure as the equipment unit 1, except for the shape of the protrusions.

[0065] 10 is a perspective view showing a part of a device unit 1B according to embodiment 2. The device unit 1B includes a PCU 3B and a boost converter 4B. The boost converter 4B is substantially the same as the boost converter 4 of embodiment 1.

[0066] PCU 3B includes a housing case 15B. A protrusion 25B is formed on an upper surface 23B of housing case 15B. Protrusion 25B is formed at the corners of long side 30B and short side 32B. Protrusion 25B includes an upper surface 35B and a curved surface 45B.

[0067] A gap 5B is formed between the boost converter 4 and the PCU 3. Gap 5B includes an opening portion 41B and an opening portion 42B arranged in the first direction D1, and an opening portion 43B and an opening portion 44B arranged in the second direction D2.

[0068] 11 is a plan view showing the device unit 1B. In the second embodiment as well, the PCU 3B and the boost converter 4B are arranged to coincide with each other.

[0069] Here, the portion of opening portion 41B located closer to short side 33B than protrusion 25B is defined as opening region R1B. The portion of opening portion 43B located closer to long side 31B than protrusion 25B is defined as opening region R3B. The portion of opening portion 42B facing opening region R1B is defined as opening region R2B. The portion of opening portion 44B facing opening region R3B is defined as opening region R4B.

[0070] Air column resonance may occur in the gap 5B. In this case, air column resonance occurs mainly between the opening region R1B and the opening region R2B and between the opening region R3B and the opening region R4B.

[0071] When air column resonance occurs between the opening regions R1B and R2B, the traveling sound wave propagates in the first direction D1. When air column resonance occurs between the opening regions R3B and R4B, the traveling sound wave propagates in the second direction D2.

[0072] Fig. 12 is a cross-sectional view taken along line XII-XII in Fig. 11. In other words, Fig. 12 is a view of protrusion 25B and opening 41B viewed in first direction D1.

[0073] Here, in a state where the protrusion 25B is not provided, the length of the opening 41B in the second direction D2 when viewed in the first direction D1 is defined as "length XB."

[0074] In a state where protrusion 25B is not provided, the vertical height of opening 41B is defined as “height HB.” In a state where protrusion 25B is not provided, the projected area of ​​opening 41B when projected in first direction D1 is defined as projected area S1B.

[0075] The length of protrusion 25B in second direction D2 when viewed in first direction D1 is defined as "L1B." The height of protrusion 25B in the height direction when viewed in first direction D1 is defined as "H1B." The projected area of ​​protrusion 25B in first direction D1 is defined as projected area S10B.

[0076] In the first embodiment, the "length L1B" is "0.423XB" and the "height H1B" is "0.95H".

[0077] Fig. 13 is a cross-sectional view taken along line XIII-XIII in Fig. 10. In other words, this is a view of opening portion 43B and protrusion 25B in second direction D2.

[0078] When the protrusion 25B is not provided, the length of the opening 43B in the first direction D1 when viewed in the second direction D2 is defined as "YB." When the protrusion 25 is not provided, the height of the opening 43 is defined as "HB."

[0079] The area of ​​opening portion 43B projected in second direction D2 is defined as opening area S2, and the area of ​​protrusion 25B projected in second direction D2 is defined as projected area S11B.

[0080] The length of the protrusion 25B in the first direction D1 when viewed in the second direction D2 is "L2B". The height of the protrusion 25B in the up-down direction when viewed in the second direction D2 is also "H1B". Here, "length L2B" is "0.437YB".

[0081] "Height HB", "height H1B", "length XB", "length YB", "length L1B" and "length L2B" satisfy the following formula (3). 100×{(L1B+L2B)×H1B} / {(XB+YB)×HB}>15(%)...(3) 10, if the vertical distance between the top surface 35B of the protrusion 25B and the bottom surface 40B of the storage case 20B is "GP1B," then GP1B is 0.05HB. For example, the distance GP1B is 1.5 mm or less.

[0082] In the equipment unit 1B configured as above, air column resonance may occur in the gap 5B. For example, in FIG. 10, air column resonance may occur between the opening region R1B and the opening region R2B.

[0083] 11, the opening area of ​​the opening region R1B is smaller than that of the opening portion 41B, and the opening area of ​​the opening region R2B is smaller than that of the opening portion 42B. Therefore, the noise generated in the equipment unit 1A shown in FIG. 9 can be reduced in the equipment unit 1B as well.

[0084] In the equipment unit 1B, air column resonance may also occur between the opening region R3B and the opening region R4B. In this case, the opening area of ​​the opening region R3B is smaller than the opening area of ​​the opening portion 43B, and the opening area of ​​the opening region R4B is smaller than the opening area of ​​the opening portion 44B. Therefore, the noise generated in the equipment unit 1B can be suppressed to be smaller than the noise generated in the equipment unit 1A.

[0085] FIG. 14 shows the increase in sound volume when air column resonance occurs in each equipment unit in which the shape of the protrusion 25B is changed in various ways.

[0086] 14, the horizontal axis indicates the frequency (KHz) of air column resonance, and the vertical axis indicates the sound pressure increase due to air column resonance. Here, the left side of the above formula (3) is defined as the projected area ratio PR of the protrusion 25B.

[0087] 14, the graph line GL1 indicates the results for an equipment unit that does not have the protrusion 25B formed therein. The projected area ratio PR1 of this equipment unit is 0(%).

[0088] The graph line GL2 is the result for an equipment unit with a projected area ratio PR2 of 12%. The graph line GL3 is the result for an equipment unit with a projected area ratio PR3 of 26%. The graph line GL4 is the result for an equipment unit with a projected area ratio PR4 of 41%.

[0089] 14, it can be seen that in each equipment unit, the sound pressure increase (dB) is highest at a frequency of P1 (KHz). In other words, it can be seen that the air column resonance frequency of each equipment unit is P1 (KHz).

[0090] Fig. 15 is a graph showing the peak increase (dB) at the air column resonance frequency P1. In the graph shown in Fig. 15, the horizontal axis shows the projected area ratio (%), and the vertical axis shows the peak increase (dB).

[0091] In Fig. 15, peak point PP1 indicates the peak point of an equipment unit where the projected area ratio PR1 is 0(%). Peak point PP2 is the peak point of an equipment unit where the projected area ratio PR2 is 12%. Peak point PP3 is the peak point of an equipment unit where the projected area ratio PR3 is 26%. Peak point PP4 is the peak point where the projected area ratio PR4 is 41(%).

[0092] As is clear from FIG. 15, when the projected area ratio PR is 15% or more, the peak point can be kept small.

[0093] Furthermore, it can be seen that the peak point can be kept small when the projected area ratio PR is 26% or more. Note that it can be seen that the peak point can be further kept small by setting the projected area ratio PR to 41%.

[0094] In other words, it is understood that the peak point can be kept small by setting the projected area ratio to at least 15% to 41%. (Embodiment 3) A device unit 1C according to the third embodiment will be described with reference to Fig. 16 etc. The device unit 1C has the same configuration as the device unit 1, except for the shape of the projections.

[0095] 16 is a perspective view showing a part of a device unit 1C according to embodiment 3. The device unit 1C includes a PCU 3C and a boost converter 4C. The boost converter 4C is substantially the same as the boost converter 4 in embodiment 1.

[0096] The PCU 3C includes a housing case 15C. A protrusion 25C is formed on an upper surface 23C of the housing case 15C. The protrusion 25C is formed in an annular shape along the outer circumferential edge of the upper surface 23C.

[0097] 17 is a plan view showing a device unit 1C. In the device unit 1C as well, the PCU 3C and the boost converter 4C are arranged so as to coincide with each other.

[0098] Fig. 18 is a cross-sectional view taken along line XVIII-XVIII in Fig. 17. Fig. 19 is a cross-sectional view taken along line IX-IX in Fig. 17.

[0099] Here, if the vertical distance between the top surface 35C of the protrusion 25C and the bottom surface 40C of the storage case 20C is taken as "distance GP1C," the distance GP1C is 1.5 mm or less. Preferably, the distance GP1C is 0.6 mm or more and 1.5 mm or less.

[0100] By setting the distance GP1C to 1.5 mm or less, the viscous resistance of the air increases, making it difficult for air column resonance to occur in the gap 5C. If the distance GP1C is set to less than 0.6 mm, there is a risk that the protrusion 25C will interfere with the boost converter 4C when the PCU 3C vibrates.

[0101] FIG. 20 is a graph showing the increase in sound volume when air column resonance occurs in each equipment unit in which the shape of the protrusion 25C is variously changed.

[0102] 20, graph line GL5 indicates the case where protrusion 25C is not provided. In this case, the distance between PCU 3 and boost converter 4C in the vertical direction is 3 mm.

[0103] The graph line GL6 shows an equipment unit including a protrusion 25C formed so that the distance GP1C is 1.2 mm. The graph line GL7 shows an equipment unit including a protrusion 25C formed so that the distance GP1C is 0.6 mm. Air column resonance occurs at the air column resonance frequency P2 in each equipment unit.

[0104] As is clear from FIG. 20, by setting the distance GP1C to 1.5 mm or less, it is possible to reduce the increase in sound pressure when air column resonance occurs.

[0105] The distance GP1C is set to 0.6 mm or more and 1.2 mm or less. If the distance GP1C is set to 1.2 mm or less, the air viscosity becomes high and air column resonance becomes less likely to occur.

[0106] On the other hand, if distance GP1C is set to be less than 0.6 mm, there is a risk that protrusion 25C may interfere with boost converter 4C when PCU 3C vibrates. (Embodiment 4) A device unit 1D according to the fourth embodiment will be described with reference to Fig. 21 etc. The device unit 1D has the same configuration except for the protrusions.

[0107] 21 is a perspective view showing a part of a device unit 1D. The device unit 1D includes a PCU 3D and a boost converter 4D.

[0108] The PCU 3D includes a housing case 15D. An upper surface 23D of the housing case 15D is formed to have a flat surface shape, and no protrusions are formed on the upper surface 23D.

[0109] A gap 5D is formed between the bottom surface 40A and the top surface 23D. Openings 41D, 42D, 43D, and 44D are formed at the outer periphery of the gap 5D. The openings 41D and 42D are arranged in the first direction D1, and the openings 43D and 44D are arranged in the second direction D2.

[0110] A distance GP1D between the gap 5D and the openings 41D, 42D, 43D, and 44D in the arrangement direction (vertical direction) of the housing case 20D and the housing case 15D is 0.6 mm or more and 1.5 mm or less.

[0111] 22 is a graph showing the increase in sound volume when air column resonance occurs when the distance GP1D between the housing case 20D and the housing case 15D is changed in various ways. The graph line GL8 shows the case where the distance GP1D is 3 mm. The graph line GL9 shows the case where the distance GP1D is 5 mm.

[0112] Graph line GL10 shows the case where distance GP1D is 6 mm. Graph line GL11 shows the case where distance GP1D is 8 mm. Graph line GL12 shows the case where distance GP1D is 1 mm. In the example shown in Fig. 21, the air column resonance frequency is "P2".

[0113] Fig. 23 is a graph showing the peak increase (dB) at the air column resonance frequency P2. In the graph shown in Fig. 23, the horizontal axis represents the distance GP1D, and the vertical axis represents the peak increase (dB).

[0114] Here, peak point PP8 indicates the peak point when distance GP1D is 3 mm. Peak point PP9 indicates the peak point when distance GP1D is 5 mm. Peak point PP10 indicates the peak point when distance GP1D is 6 mm. Peak point PP11 indicates the peak point when distance GP1D is 8 mm. Peak point PP12 indicates the peak point when distance GP1D is 1 mm.

[0115] As is clear from FIG. 23, it can be seen that the resonance sound generated in the gap 5D can be reduced at the air column resonance frequency P2 by setting the distance GP1D to 0.6 mm or more and 1.5 mm or less. When the distance GP1D is set to 1.5 mm, the resonance sound is smaller than the resonance sound at the peak point PP11. This is because when the distance GP1D is smaller than 0.6 mm, the housing case 20D and the housing case 15D come into contact with each other even if they vibrate slightly. The resonance sound can be further reduced by setting the distance GP1D to 0.6 mm or more and 1.2 mm or less. The resonance sound can be further reduced by setting the distance GP1D to 0.6 mm or more and 1.0 mm or less. (Embodiment 5) In the above first to third embodiments, the protrusions are formed on the storage cases 15, 15B, and 15C. However, the protrusions may be formed on the storage case 20.

[0116] Fig. 24 is a perspective view showing an equipment unit 1E according to embodiment 5. Fig. 25 is a cross-sectional view showing the equipment unit 1E. In this equipment unit 1E, a protrusion 25E is formed on a bottom surface 40E of a storage case 20E. The shape of the protrusion 25E is substantially the same as that of the protrusion 25 in embodiment 1. The equipment unit 1E provided with this protrusion 25E can also achieve the same effects as the equipment unit 1 according to embodiment 1.

[0117] The embodiments disclosed herein should be considered to be illustrative and not restrictive in all respects. The scope of the present invention is defined by the claims, and it is intended to include all modifications within the scope and meaning equivalent to the claims. [Explanation of symbols]

[0118] 1,1A,1B,1C,1D,1E Equipment unit, 2 Transaxle, 4,4A,4B,4C,4D Boost converter, 5,5A,5B,5D Gap, 10,15,15A,15B,15C,15D,20,20A,20B,20C,20D,20E Storage case, 11,12 Rotating electric machine, 13 Transmission, 16 Inverter, 21 Boost circuit, 22,40,40A,40B,40C,40E Bottom surface, 23,23B,23C,23D,35,35B,35C Top surface, 24 Peripheral surface, 25,25B,25C,25E Protrusion, 26,27 Long side, 28,29 Short side, 30,30B,31,31B Long side, 32, 32B, 33, 33B Short side, 36, 37 One side, 41, 41A, 41B, 41D, 42, 42A, 42B, 42D, 43, 43A, 43B, 43D, 44, 44A, 44B, 44D Opening, 45B Curved surface, D1 1st direction, D2 2nd direction, GL1, GL2, GL3, GL4, GL5, GL6, GL7, GL8, GL9, GL10, GL11, GL12 Graph line, GP1B, GP1, GP1C, GP1D Distance, H, H1, H1B, HB Height, L1B, L1, L2, L2B, X, XB, Y, YB Length, P1, P2 Air column resonance frequency, PP1,PP2,PP3,PP4,PP8,PP9,PP10,PP11,PP12 Peak point, PR,PR1,PR2,PR3,PR4 Projected area ratio, R1,R1B,R2,R2B,R3B,R3,R4B,R4 Opening area, S1B,S10,S10B,S11,S11B Projected area, S1, S2 aperture area.

Claims

[Claim 1] a first device that vibrates; a second device disposed with a gap between the first device and the second device; A protrusion is disposed on the outer periphery of the gap and is formed so as to narrow the gap; An equipment unit comprising: The direction in which a traveling sound wave of air column resonance generated in the gap propagates in a state in which the protruding portion is not provided is defined as a propagation direction, When the protrusion is not provided, an area of ​​the gap projected in the propagation direction is defined as an opening area; If the area of ​​the protrusion when projected in the propagation direction is defined as a protrusion area, The protruding area is 26% or more and 41% or less of the opening area, An equipment unit, wherein the protrusion is formed so as to protrude from the first device toward the second device, and a gap between the protrusion and the second device is 1.5 mm or less.

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