Engine with electronics

Abstract

To provide an engine with electronic equipment capable of giving no harmful effects to 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 mounted to the intake side of the cylinder block 2 using a fixing mechanism 6 for promoting heat conduction, and the fixing mechanism 6 is constructed into the state that the cylinder block 2 and the electronic equipment 22 face-contact each other. The fixing mechanism 6 is constructed using a bolt 7 to be fixed to a cylinder part 2s of the cylinder block 2.SELECTED DRAWING: Figure 3

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 electronic equipment for the engine is attached to the intake side of the cylinder block or cylinder head using a fixing mechanism that can promote heat conduction. Installed, the fixing mechanism is configured using a bolt fixed to a cylinder portion of the cylinder block, The bolt is a stud bolt implanted in the boss portion of the cylinder portion, and a collar is provided between the boss portion and an attachment portion in the electronic device through which the stud bolt passes, so that a predetermined space is formed between the cylinder portion and the electronic device.

[0010] Regarding the present invention, the characteristic configurations and means other than the above-mentioned configurations (means) are as follows: Claims 2 and 3 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 cylinder block or cylinder head, it is possible to minimize the thermal effects from the engine.

[0012] Furthermore, because the electronic devices are attached using a fixing mechanism that can promote thermal conduction, heat generated in the electronic devices can be quickly dissipated to the cylinder block or cylinder head through the fixing mechanism. The heat transmitted from the electronic devices is absorbed by the cooling water flowing inside the cylinder block or cylinder head, and is quickly released.

[0013] Furthermore, since cooling air from a cooling fan typically flows along the sides of the cylinder block or cylinder head, the engine receives not only the water-cooling effect of the cooling water but also the air-cooling effect of the cooling air, making it possible to place electronic equipment next to the cylinder block or cylinder head 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. [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 engine ECU (hereinafter simply referred to as ECU) 22, which is an electronic device 22 for the engine E, is disposed on the intake side (right side) of the cylinder block 2 and on the right side of the cylinder section 2s using a fixing mechanism 6. The ECU (also ECU assy) 22 is attached to a portion immediately below the intake manifold 19 on the side of the cylinder block 2.

[0022] The ECU 22 is configured to include 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 protrudes 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 four ECU mounting portions 22a at the top, bottom, front, and rear ends are attached to the cylinder portion 2s (on the cylinder side wall) by fixing mechanisms 6 in a vertical orientation so that the left-right length is small (see FIG. 2(A)). A flat space 21 with a narrow left-right width is formed between the left and right sides of the cylinder portion 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 (multiple) fixing mechanisms 6 at its front, rear, top and bottom, and the ECU mounting portion 22a is fastened to a stud bolt 7 attached to a boss portion 2i formed on the right wall of the cylinder portion 2s with a nut 9 via a collar 8. The mounting structure of the ECU 22 to the cylinder portion 2s is configured as follows, depending on the relative temperatures of the ECU 22 and the cylinder portion 2s.

[0025] That is, it has been found that the ECU 22 in a powered and in use state reaches a fairly high temperature (approximately 100 degrees Celsius), which is higher than the temperature (70 to 80 degrees Celsius) on the intake side of the cylinder section 2s of the engine that is the subject of the present invention. In other words, when the engine is in operation, it is possible to cool the ECU 22 using the cylinder block 2.

[0026] Therefore, the fixing mechanism 6 employs a collar 8 made of a material with excellent thermal conductivity (aluminum alloy, steel (e.g., SS400), etc.), and is structured to efficiently conduct heat between the boss portion 2i and the ECU mounting portion 22a. Furthermore, if the outer diameter of the cylindrical collar 8 is made larger than usual and the right end face of the boss portion 2i and the ECU mounting portion 22a are configured to be in surface contact with the collar 8, the heat transfer area can be increased, which is advantageous. 。 As shown in the blow-out diagram of FIG. 3, a filler 7A made of a highly conductive material may be provided to improve the thermal conductivity between the stud bolt 7 and the ECU mounting portion 22a.

[0027] For example, the material of the boss portion 2i is cast iron (e.g., FC250), the material of the ECU mounting portion 22a (ECU case 22A) is aluminum alloy (e.g., ADC10 or 12), the contact area (total of four locations) between the boss portion 2i and the collar 8 is set to 120 to 130 (e.g., 126.4) square millimeters, and the contact area (total of four locations) between the collar 8 and the ECU mounting portion 22a is set to 110 to 120 (e.g., 112.4) square millimeters.

[0028] As a result (as described above), heat is conducted between the boss portion 2i and the ECU mounting portion 22a over a wide area in the four fixing mechanisms 6 by the collars 8 and the stud bolts 7, so that heat generated by the ECU 22 is quickly dissipated 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, thereby cooling the ECU 22. Note that by attaching the collars 8, the left and right width of the space portion 21 is set to allow easy passage of cooling air w (=predetermined space portion 21) (see FIG. 3).

[0029] 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.

[0030] 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.

[0031] That is, the heat generated in the ECU 22 is quickly conducted to the cylinder portion 2s through the four fixing mechanisms 6, and the conducted heat is discharged by the cooling water m, resulting in the effect of cooling not only the cylinder portion 2s but also the ECU 22 with the cooling water m. Note that, in order to further enhance the water cooling effect, it is possible to increase the number of fixing mechanisms 6 or increase the contact area between the boss portion 2i and the ECU mounting portion 22a. 。

[0032] 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.

[0033] 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.

[0034] 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. 6). 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)).

[0035] 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 cylinder block 2 in the cylinder arrangement direction (front-rear direction), and recessed portions 2k and 10A are formed in the cylinder block 2 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.

[0036] 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.

[0037] 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).

[0038] 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).

[0039] 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.

[0040] 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.

[0041] 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 is not limited to this. Also, the recessed section 2k of the cylinder 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 recessed section 2k (see Figure 5(A)) that linearly leans leftward as it goes rearward, or may be a concave or convex surface leaning leftward.

[0042] Conventionally, ECUs have a limited heat resistance temperature, and when installed in the engine case C (cylinder block 2, cylinder head 14, etc.), cooling is only possible at the mounting point. This means that either the ECU must be installed in the engine case C, which raises concerns about heat resistance, or the ECU must be installed separately from the engine, which would require more complex and longer wiring. In contrast, in the present invention, a fixing mechanism 6 capable of promoting heat conduction is attached to the intake side surface of the cylinder section 2s (or cylinder head 14), and the fixing mechanism 6 is configured to be in surface contact with the ECU 22 using bolts 7 fixed to the cylinder block 2 or cylinder head 14.

[0043] Such structural innovations can provide the following effects (1) to (6). (1) The ECU 22 can be cooled not only by the air-cooling effect of the cooling air w but also by the water-cooling effect of the cooling water m. (2) The engine including the ECU 22, specifically the cylinder section 2s, can be made more compact. (3) No need for separate space for the conventional ECU (4) The ECU22 can be placed on the engine itself, which shortens and simplifies the wiring. (5) The ECU 22 located next to the cylinder section 2s acts as a sound barrier, reducing noise. (6) A streamlined configuration has been achieved in which the cooling water m used to cool the cylinder section 2s can also cool the ECU 22.

[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. In addition to the ECU, the engine electronic device 22 may include a fuel injector, an ignition coil with a microcomputer, various sensors, and the like. [Reference form] As a reference embodiment, the following configuration is possible. The boss portion 2i and the ECU mounting portion 22a are in direct contact over a wide area without the intervention of the collar 8. The collar 8 is omitted, and the ECU 22 and the cylinder section 2s are in direct contact with each other. [Explanation of symbols]

[0045] 2 Cylinder block 2i Boss part 2s Cylinder section 6 Fixing mechanism 7 bolts (stud bolts) 8 colors 14 Cylinder head 16 Cooling fan 21 Space section 22 Engine electronics unit (ECU) 22a Mounting part d. Air guide member w Cooling air

Claims

1. The electronic device for the engine is attached to the intake side of the cylinder block or the cylinder head using a fixing mechanism that can promote heat conduction, the fixing mechanism is configured using a bolt fixed to a cylinder portion of the cylinder block, The bolt is a stud bolt implanted in a boss portion of the cylinder portion, and a collar is provided between the boss portion and an attachment portion of the electronic device through which the stud bolt passes so that a predetermined space is formed between the cylinder portion and the electronic device.

2. 2. The engine with electronic equipment according to claim 1, wherein a cooling fan is provided at one end of the cylinder block in the cylinder arrangement direction, and an air guide member is provided to guide cooling air from the cooling fan to the electronic equipment.

3. 3. The engine with electronic equipment according to claim 1, wherein the electronic equipment is an ECU for engine control.

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