Engine with electronics

Abstract

To provide an engine with electronic equipment capable of giving no harmful effects to the electronic equipment due to heat by further devising the structure to effortlessly reduce the thermal load of the electronic equipment mounted on the engine, such as an ECU.SOLUTION: The engine with electronic equipment has electronic equipment 22 for the engine arranged in an area right below an intake manifold 19 on the lateral side of the intake side of a cylinder part 2s. A cooling fan 16 is provided on one end side in the cylinder arrangement direction of a cylinder block 2, and recessed parts 2k, 10A are formed in the cylinder block 2 and a timing transmission case 10, respectively, so that cooling air w by the cooling fan 16 is promoted to cover the electronic equipment 22.SELECTED DRAWING: Figure 1

Description

[Technical Field]

[0001] The present invention relates to an engine equipped with electronic devices such as an ECU, that is, an engine equipped with electronic devices. [Background technology]

[0002] In recent electronically controlled engines, it is advantageous to provide an ECU for engine control (engine ECU, hereinafter simply referred to as ECU) in the engine itself as much as possible from the viewpoint of streamlining, such as shortening wiring etc. For example, Patent Document 1 (see FIG. 4) discloses that the ECU (15) is disposed on the side of the cylinder block (21).

[0003] In Patent Document 2, as shown in FIGS. 1 to 3, the ECU (40) is disposed on the cylinder head (3). [Prior art documents] [Patent documents]

[0004] [Patent Document 1] Japanese Patent Publication No. 2022-11786 [Patent Document 2] Japanese Patent Application Laid-Open No. 2009-209699 Summary of the Invention [Problem to be solved by the invention]

[0005] The ECU is an electronic device (electronic component) that is inherently thermally vulnerable, so it would be desirable to install it separately from the engine, but as mentioned above (rationalization, etc.), the reality is that it is attached to the engine.

[0006] Therefore, in order to reduce the heat conduction to the ECU, various measures have been taken to attach it to the engine (engine body), such as bolting it to the cylinder block via a heat insulating material.However, since there is a limit to the heat temperature that the ECU can withstand, there is still room for improvement in improving the thermal environment of the ECU so that it can cope with the increased thermal load caused by output improvements, etc.

[0007] The object of the present invention is to provide an engine with electronic equipment that, through further structural innovation, can reasonably reduce the thermal load on electronic equipment attached to the engine, such as an ECU, thereby preventing the electronic equipment from being adversely affected by heat. [Means for solving the problem]

[0008] The present invention relates to an engine with electronic equipment, in which the electronic equipment for the engine is located on the intake side of the engine case and on the side of the cylinder section. a cooling fan is provided at one end side of the engine case in a cylinder arrangement direction, a recessed portion is formed in a portion of the engine case between the cooling fan and the electronic device, which can promote the cooling air from the cooling fan to reach the electronic device, an air guide member is provided in the engine case to guide the cooling air from the cooling fan to the electronic device, the air guide member is provided at a position corresponding to the recessed portion in the flow direction of the cooling air, the electronic device is an ECU for engine control, the engine is a vertical engine, the direction in which a crankshaft is installed is a front-rear direction, in the front-rear direction, the side where the cooling fan is located is defined as the front side and the side opposite to the front side is defined as the rear side, the width direction of the engine case which intersects with the front-rear direction is defined as the left-right direction, and an ECU case of the ECU is The air guide member has a rectangular shape in a side view and is elongated in the front-rear direction in a plan view, and a flat space with a narrow left-right width is formed between the cylinder section and the ECU case, the air guide member faces the recessed portion in the left-right direction and is composed of an inclined plate material that gradually approaches the ECU case from the front to the rear in a plan view, and a plate portion along the front-rear direction is provided on the rear side of the air guide member, and the plate portion faces the ECU case in the left-right direction, and the cooling air from the cooling fan that passes through the recessed portion is guided by the guiding action of the air guide member to the air guide space portion between the air guide member and the recessed portion, and flows rearward through the flat space portion between the ECU case and the cylinder section, and a portion of the cooling air flows rearward through the gap portion between the ECU case and the plate portion. It is characterized by:

[0009] In this case, it is convenient for the electronic device to be attached to a portion of the cylinder block immediately below the intake manifold. 。

[0010] Regarding the present invention, the characteristic configurations and means other than the above-mentioned configurations (means) are as follows: Claims 3 and 4 Please refer to. [Effects of the Invention]

[0011] According to the present invention, in an engine, the intake side to which room temperature air is supplied is relatively cooler than the exhaust side to which high temperature exhaust gas flows. Therefore, by arranging electronic devices such as an ECU on the intake side, which is the cooler side of the engine case (cylinder block, etc.), it is possible to minimize the thermal effects from the engine case.

[0012] Furthermore, since the electronic devices are arranged on the side of the cylinder section, which has a smaller lateral protrusion compared to the crankcase section in terms of dimensions, the engine case does not take up much lateral bulk, even though the electronic devices are arranged therein.

[0013] In addition, cooling air is generally blown along the side of the engine case by a cooling fan, so in addition to the intake side, which has a lower ambient temperature to begin with, the cooling air also has an air-cooling effect, making it possible to place electronic equipment next to the engine case while minimizing the thermal load.

[0014] As a result, through further structural innovations, it is possible to provide an engine with electronic equipment that can reasonably reduce the thermal load on electronic equipment attached to the engine, such as an ECU, and prevent the electronic equipment from being adversely affected by heat.

[0015] In this case, it would be advantageous to mount the electronic equipment directly below the intake manifold, which is cooler than the engine case, as this would further reduce the thermal load. Furthermore, it would be even more advantageous to form a recess in the engine case between the cooling fan and the electronic equipment, allowing more cooling air to flow to the electronic equipment. [Brief explanation of the drawings]

[0016] [Figure 1] An enlarged side view of the main part showing the ECU mounting structure and its surrounding structure [Figure 2] (A) A cross-sectional view of the main part showing the cooling water flowing through the cylinder and the ECU, etc. (B) A vertical cross-sectional view of the main part showing the recessed part of the cylinder [Figure 3] Vertical cross-sectional view of the ECU and its mounting structure (with balloon diagram) [Figure 4] Cross-sectional view of the main part of the cylinder block showing the airflow structure to the ECU [Figure 5] (A) is a plan view including a part of the surrounding structure, (B) is a side view, and (C) is a front view showing the harness support. [Figure 6] Front view of the engine [Figure 7] Right side view of the engine [Figure 8] Engine plan view [Figure 9] Rear view of the engine DETAILED DESCRIPTION OF THE INVENTION

[0017] An embodiment of an engine with electronic equipment according to the present invention will be described below with reference to the drawings, focusing on a common-rail vertical in-line three-cylinder diesel engine that is used in industrial equipment such as agricultural machinery, construction machinery, and generators. In Figures 6 to 9 and other figures, the side of the crankshaft 1 where the cooling fan 16 is located is the front, the side where the flywheel 17 is located is the rear, the side where the intake manifold 19 is located is the right, and the side where the exhaust manifold 20 is located is the left.

[0018] 6 to 9, the diesel engine E has a cylinder head 14 mounted on top of a cylinder block 2, a head cover 15 mounted on top of the cylinder head 14, and an oil pan 18 mounted below the cylinder block 2. The cylinder block 2 has an upper cylinder section 2s and a lower crankcase section 2h.

[0019] A timing transmission case 10 is mounted in front of the cylinder block 2 and on the front of the oil pan 18, and a transmission belt 11 is wound around a fan pulley (notation omitted) of a cooling fan (engine cooling fan) 16 arranged in front of the timing transmission case 10, and a drive pulley (notation omitted) of the crankshaft 1 extending forward and backward in the crankcase section 2h.

[0020] An intake manifold 19 is attached to the right side (one lateral side) of the cylinder head 14, and an exhaust manifold 20 is attached to the left side (the other lateral side). 3 is a fuel injection device that also serves as a common rail fuel injection device 3a, and is equipped with a common rail 3b and fuel injectors 3c that inject liquid fuel stored under pressure in the common rail 3b into each cylinder. 4 is a fuel pressure pump that also serves as a fuel supply pump 4a.

[0021] 1 to 3, an ECU assy (electronic device assy) 6 including an engine ECU (hereinafter simply referred to as ECU) 22, which is an electronic device for the engine E, is disposed on the intake side (right side) of the cylinder block 2 (an example of the engine case C) and on the right side of the cylinder section 2s. The ECU assy 6 is attached to a portion of the side of the cylinder block 2 directly below the intake manifold 19.

[0022] The ECU assembly 6 includes an ECU case 22A that houses an ECU board (ECU electronic board) 22B that has heat-generating electronic elements such as power transistors, and connection terminals 22C such as couplers. The connection terminals 22C are provided on the ECU case 22A in a state that they protrude to the right from the ECU case 22A (toward the opposite side of the cylinder block in the left-right direction).

[0023] The ECU case 22A has a rectangular shape close to a square in side view (see FIG. 1), and is screwed to the cylinder section 2s (on the cylinder side wall) at four ECU mounting portions 22a at the top, bottom, front, and rear ends in a vertical orientation so that its left-right length is small (see FIG. 2(A)). A flat space 21 with a narrow left-right width is formed between the cylinder section 2s and the ECU case 22A. Although not shown in FIG. 1, for example, a wire harness 23 is connected to a connection terminal 22C of the ECU 22 (see FIG. 7).

[0024] 1 and 3, the ECU 22 has four (plural) ECU mounting portions 22a at its front, rear, top and bottom, which are fastened to stud bolts 7 attached to bosses 2i formed on the right wall of the cylinder section 2s with nuts 9 via collars 8. The mounting structure of the ECU 22 to the cylinder section 2s can be selected and set depending on the relative temperatures of the ECU 22 and the cylinder section 2s.

[0025] First, when the temperature of the ECU 22 is higher than that of the cylinder portion 2s (on its intake side) (for example, when the ECU 22 is around 100°C and the cylinder portion 2s is 70-80°C), the collar 8 should be made of a material with excellent thermal conductivity (aluminum alloy, steel, etc.) to ensure efficient heat conduction between the boss portion 2i and the ECU mounting portion 22a. Furthermore, for example, by making the outer diameter of the cylindrical collar 8 larger than usual and configuring it so that the right end face of the boss portion 2i and the ECU mounting portion 22a are in surface contact with the collar 8, this is advantageous because it increases the heat transfer area. Alternatively, the boss portion 2i and the ECU mounting portion 22a may be in direct contact over a wide area without the collar 8 being interposed therebetween.

[0026] As a result (as described above), heat is conducted between the boss portion 2i and the ECU mounting portion 22a over a wide area at the four stud bolts 7, so that heat generated by the ECU 22 is quickly released to the cylinder portion 2s, preventing the ECU 22 from generating more heat than necessary. In other words, the mounting structure of the ECU 22 makes it possible to efficiently transfer heat from the ECU 22 to the cylinder portion 2s and cool the ECU 22.

[0027] Next, if the temperature of the ECU 22 is lower than that of the cylinder section 2s (on its intake side) (for example, if the ECU 22 is around 60°C and the cylinder section 2s is 80-90°C), the collar 8 is made of a material with excellent heat insulation properties (heat-resistant synthetic resin, mica, etc.) to insulate the boss section 2i from the ECU mounting section 22a. As shown in the blow-out diagram of FIG. 3, a cylindrical spacer 7A with heat insulation properties may be provided between the stud bolt 7 and the ECU mounting section 22a. Also, although not shown, a washer with heat insulation properties may be provided between the nut 9 and the ECU mounting section 22a.

[0028] Regarding the insulating mounting of the ECU 22, it is possible to adopt the following: (1) the collar 8 has insulating properties; (2) a cylindrical insulating spacer 7A (see the blow-out diagram in Figure 3) is provided between the ECU mounting portion 22a and the stud bolt 7; (3) an insulating washer (not shown) is provided between the nut 9 and the ECU mounting portion 22a; (4) an insulating washer is provided between the collar 8 and the ECU mounting portion 22a; (5) the ECU mounting portion 22a itself has insulating properties; or to adopt a combination of multiple of these structures (1) to (5).

[0029] 1 and 7, a harness support A, which is a support member for the wire harness 23, is provided below the front of the ECU 22. The harness support A is a sheet metal member including a support plate portion 12 having a surface extending in the front-rear and up-down directions, a connecting plate portion 24 having a surface extending in the left-right and up-down directions and continuing to the front end of the support plate portion 12, and an air guide portion 13 having a surface extending diagonally in the front-rear and up-down directions and continuing to the front end of the connecting plate portion 24.

[0030] 1 and 5, the harness support A is a sheet metal member attached to the cylinder portion 2s by bolting a connecting plate 24 at multiple locations to the rear surface of a vertical rib 2j protruding rightward from the cylinder portion 2s. The support plate 12 having an attachment piece 12a covers the front lower portion of the ECU 22 in the left-right direction, and the wire harness 23 is supported on its right surface using the attachment piece 12a (see FIG. 5(B)). 29 denotes a weld nut for fastening the wire harness 23 to a support member (such as a cable tie, not shown), and 31 denotes a hole.

[0031] The air guide portion 13, which extends diagonally forward and slightly to the right in a plan view (see FIG. 8), is located in front of the vertical center of the ECU 22 (see FIG. 1), and, together with the upper part of the connecting plate portion 24, constitutes an air guide member d that guides the cooling air w from the cooling fan 16 to the ECU 22, the gap 28 between the ECU 22 and the harness support A (support plate portion 12), and the space portion 21 (see FIG. 5(A)). The air guide member d is provided at a vertical position corresponding to each of the recesses 10A and 2k in the flow direction of the cooling air w (as viewed in the front-rear direction) (see FIG. 1). The connecting plate portion 24 functions to guide the wiring of the wire harness 23, and the air guide member d also functions to guide the air (see FIGS. 5(A) and 5(B)).

[0032] 1 and 3, a recessed portion 2k of the cylinder and a recessed portion 10A of the transmission case are formed at the right front end of the cylinder portion 2s and the right central portion of the timing transmission case 10, respectively, to facilitate rearward guidance of the cooling air w from the cooling fan 16. In other words, the cooling fan 16 is provided at one end (front side) of the engine case C in the cylinder arrangement direction (front-rear direction), and recessed portions 2k, 10A are formed in the engine case C between the cooling fan 16 and the ECU 22, which can facilitate the cooling air w from the cooling fan 16 reaching the ECU 22.

[0033] As shown in Fig. 6, the recessed portion 10A of the transmission case is located to the right of the camshaft input gear chamber 10b that houses the camshaft input gear (not shown) in the timing transmission case 10, between the oil injection portion 10a and the temporary rotating shaft input gear chamber 10c, and is recessed to the left between the vertically adjacent bolt fastening portions 10d and 10e. The temporary rotating shaft input gear chamber 10c rotates integrally with the temporary rotating shaft (not shown) and houses the temporary rotating shaft input gear (not shown) that meshes with the camshaft input gear. Although not shown, the temporary rotating shaft may be a PTO shaft, governor shaft, balancer shaft, etc.

[0034] Cylinder recess 2k is a portion that is recessed significantly to the left between pump mounting portion 25, which accommodates fuel pressure pump 4 in cylinder section 2s, and insert part housing 26, which accommodates a temporary rotating shaft, etc., without interfering with camshaft housing chamber 27 (see FIG. 2(B)). As shown in FIG. 4, recess surface 36, which is recessed to the farthest left in cylinder recess 2k, is set to a length that is approximately equivalent to the entire length (front-to-back length) of recess 2k, but may be an inclined surface, as shown in FIG. 5(A).

[0035] As the cooling fan 16 rotates, cooling air w flows from front to rear around the engine, particularly on the left and right sides of the cylinder block 2 and the cylinder head 14, along the left and right side walls (not shown) of the cylinder block 2 and the cylinder head 14. Therefore, the cooling air w also flows to the ECU 22 located on the right side of the cylinder section 2s, and the ECU 22 is cooled by the cooling air, but measures are taken to further enhance the air cooling effect (recesses 2k, 10A and air guide member d).

[0036] Therefore, the cooling air w from the cooling fan 16 that passes through the recessed portion 10A of the transmission case and the recessed portion 2k of the cylinder is guided by the air guide portion 13 into the air guide space 30 between the left and right of the air guide member d and the recessed portion 2k of the cylinder. By passing through the air guide space 30, the direction of the cooling air w is guided rearward and leftward, and some enters the gap 28 to the right of the ECU 22 and flows rearward, while some enters the space 21 to the left of the ECU 22 and flows rearward. Note that Figure 5(A) includes a conceptual diagram showing how the ECU 22 is air-cooled by the cooling air w using the recessed portions 2k, 10A and the air guide member d.

[0037] In this way, by forming the recessed portions 10A, 2k in the timing transmission case 10 and the cylinder portion 2s, respectively, and by devising the shape of the harness support A, which is a member for supporting the wire harness 23, it is possible to gather and flow the cooling air w around the ECU 22, even though the ECU 22 is located to the right of the cylinder portion 2s, which is recessed to the left compared to the timing transmission case 10. As a result, the ECU 22 can be mounted to the right of the cylinder portion 2s, so that the engine E does not take up too much space to the right, and the ECU 22 can be efficiently cooled by the cooling air w.

[0038] As shown in Figures 4 and 5(A), the inclination angle of the air guide section 13 relative to the front-to-rear direction is drawn at 10 degrees (5 to 15 degrees), but this is not limited to this. Furthermore, the cylinder recess 2k may have a structure having a long recessed surface 36 parallel to the front-to-rear direction (see Figure 4), or may be an inclined surface-like recess 2k that linearly leans leftward as it goes rearward (see Figure 5(A)). Furthermore, it may be a concave or convex surface leaning leftward. In this specification, the engine case C is a concept that includes the cylinder block 2 (cylinder section 2s, crankcase section 2h), cylinder head 14, head cover 15, timing transmission case 10, etc.

[0039] As shown in Figures 2 to 4, cooling water passages 33, 34 extending in the front-to-rear direction are formed on the right and left sides of the cylinder tube (cylinder barrel) 32 of the cylinder section 2s, and these right cooling water passage 33 and left cooling water passage 34 are connected by an inter-bore water passage 35 (see Figure 2(A)) formed to extend left and right at the front and rear of each cylinder tube 32.

[0040] As shown in Fig. 2(A), the cooling water m mainly flows from front to rear through the left and right cooling water passages 33, 34 (see Fig. 3) to cool the cylinder section 2s, but the right side (intake manifold side) of the cylinder section 2s is particularly well cooled by the cooling water m that flows strongly through the right cooling water passage 33. This strong cooling effect on the right side of the cylinder section 2s is also configured to enable cooling of the ECU 22 located immediately to the right of the cylinder section 2s.

[0041] For example, if the cooling water m can cool not only the cylinder 2s but also the ECU 22, it is advisable to use a material with a high heat transfer coefficient (that transfers heat easily) for the collar 8. Also, by changing the length of the collar 8, it is possible to change the size of the space 21 between the cylinder 2s and the ECU 22 (change the amount of cooling air w that can be taken in).

[0042] Previously, ECUs had a limit to the heat resistance temperature, and when installed in the engine case, the only way to cool them was through the mounting part. This meant that either installing the ECU in the engine case, despite concerns about heat resistance, or installing it separately from the engine, which meant accepting longer and more complex wiring. In contrast, in the present invention, the ECU 22 is mounted on the intake side surface of the cylinder section 2s, floating (slightly spaced to the right) so that a space 21 is formed between the left and right sides of the cylinder section 2s, and recessed portions 2k, 10A recessed to the left are formed in the cylinder section 2s and timing transmission case 10 located in front of it (allowing the pump chamber to be recessed naturally), and a wind guide member d (harness support A) is provided corresponding to each recessed portion 2k, 10A.

[0043] Such structural innovations can achieve the following effects (1) to (6): (1) The recesses 2k, 10A allow the cooling air w to easily pass through the ECU 22; (2) The engine including the ECU 22, more precisely the cylinder section 2s, can be made more compact; (3) A separate space for the ECU as in the past is no longer necessary; (4) The ECU 22 can be placed on the engine itself, which shortens and simplifies the wiring; (5) The ECU 22 placed next to the cylinder section 2s acts as a sound barrier, resulting in a noise reduction effect; and (6) A streamlined configuration is realized in which the harness support A also serves as the air guide member d. 。 (summary) In the embodiment of the present invention, as shown in FIGS. 1 and 4, the engine is a vertical engine, the direction in which the crankshaft 1 is installed is the front-rear direction, the side of the front-rear direction where the cooling fan 16 is located is the front side, the side opposite to the front side is the rear side, and the width direction of the engine case C intersecting with the front-rear direction is the left-right direction, and as shown in FIG. 1, an ECU case 22C of the ECU is rectangular in a side view seen in the left-right direction, and as shown in FIG. 4, it is formed long in the front-rear direction in a plan view, and a flat space portion 21 having a narrow left-right width is formed between the cylinder portion 2s and the ECU case 22C, and as shown in FIG. 4, the air guide member d faces the recessed portion 2k in the left-right direction and advances from the front to the rear in a plan view. The cooling fan 16 is configured to be made of an inclined plate material that gradually approaches the ECU case 22C as it approaches the cylinder portion 2s, and a plate portion 12 extending along the front-to-rear direction is provided on the rear side of the air guide member d, and the plate portion 12 faces the ECU case 22C in the left-to-right direction. As shown in FIG. 4, of the cooling air from the cooling fan 16, the cooling air w that passes through the recessed portions 2k·10A is guided by the guiding action of the air guide member d to the air guide space portion 30 between the air guide member d and the recessed portion 2k, and flows rearward through the flat space portion 21 between the ECU case 22A and the cylinder portion 2s, and a portion of the cooling air w flows rearward through the gap portion 26 between the ECU case 22A and the plate portion 12.

[0044] [Another embodiment] The electronic device 22 such as an ECU may be provided slightly below the intake manifold 19 in the cylinder block 2 . [Reference form] The electronic devices 22 for the engine may include, in addition to the ECU, a fuel injector, an ignition coil with a microcomputer, various sensors, and the like. [Explanation of symbols]

[0045] 2 Cylinder block 2s Cylinder section 10 Transmission case 10A Recessed section 16 Cooling fan 19 Intake manifold 22 Engine electronics unit (ECU) 23 Wire harness A Support member (harness support) C Engine case d. Air guide member w Cooling air

Claims

1. The electronic equipment for the engine is arranged on the intake side of the engine case and on the side of the cylinder section, a cooling fan is provided at one end side of the engine case in a cylinder arrangement direction, and a recess is formed in a portion of the engine case between the cooling fan and the electronic device, which can promote the cooling air from the cooling fan to reach the electronic device; an air guide member is provided in the engine case to guide the cooling air from the cooling fan to the electronic equipment; the air guide member is provided at a position corresponding to the recess in the flow direction of the cooling air, the electronic device is an ECU for engine control, The engine is a vertical engine, and the direction in which the crankshaft is installed is defined as the front-rear direction, and in the front-rear direction, the side where the cooling fan is located is defined as the front side, and the side opposite to the front side is defined as the rear side. The width direction of the engine case that intersects with the front-rear direction is defined as the left-right direction. an ECU case of the ECU is rectangular in side view in the left-right direction and is elongated in the front-rear direction in plan view, and a flat space portion having a narrow left-right width is formed between the cylinder portion and the ECU case; the air guide member is opposed to the recessed portion in the left-right direction, and is composed of an inclined plate material that gradually approaches the ECU case from the front side to the rear side in a plan view, and a plate portion is provided on the rear side of the air guide member along the front-rear direction, and the plate portion faces the ECU case in the left-right direction, The engine with electronic equipment is configured such that, of the cooling air from the cooling fan, the cooling air that passes through the recess is guided by the guiding action of the air guide member into the air guide space between the air guide member and the recess, and flows rearward through the flat space between the ECU case and the cylinder portion, and a portion of the cooling air flows rearward through the gap between the ECU case and the plate portion.

2. 2. The engine with electronic equipment according to claim 1, wherein the electronic equipment is attached to a portion of the cylinder block immediately below an intake manifold.

3. 3. The engine with electronic equipment according to claim 1, wherein the recess is formed in a transmission case attached to the cooling fan side of the cylinder block.

4. 3. The engine with electronic equipment according to claim 1, wherein the air guide member is formed using a support member for a wire harness.

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