Engine unit

Abstract

To provide an engine unit that can effectively cool a sensor that detects a rotated position of a rotor of a generator.SOLUTION: The engine unit includes: a cylinder; a crank shaft coupled to a piston in the cylinder; a crank case that stores the crank shaft; a generator having a rotor that rotates with the crank shaft, and a stator opposite to the rotor, and generating power when the rotor rotates; a sensor that detects a rotated position of the rotor; and a coolant flow path having an ejection port and guiding a coolant to the ejection port to eject the coolant toward the sensor through the ejection port.SELECTED DRAWING: Figure 9

Description

Technical Field

[0001] The present disclosure relates to an engine unit.

Background Art

[0002] As an engine unit for a motorcycle or the like, an engine unit equipped with an alternator, for example, an integrated starter generator (ISG), is known. This type of engine unit includes a sensor for detecting the rotational position of the rotor of the generator (see, for example, Patent Document 1).

Prior Art Documents

Patent Documents

[0003]

Patent Document 1

Summary of the Invention

Problems to be Solved by the Invention

[0004] During engine operation, the generator may become hot, and there is a need for an engine unit that effectively cools a sensor for detecting the rotational position of the rotor.

[0005] Therefore, an object of the present disclosure is to provide an engine unit that can effectively cool a sensor for detecting the rotational position of the rotor of the generator.

Means for Solving the Problems

[0006] To solve the above problems, an engine unit according to one aspect of the present disclosure includes a cylinder, a crankshaft connected to a piston in the cylinder, a crankcase that houses the crankshaft, a rotor that rotates together with the crankshaft, and a stator facing the rotor. The engine unit further includes a generator that generates electricity when the rotor rotates, a sensor that detects the rotational position of the rotor, and a coolant flow path that has a jet outlet, guides coolant to the jet outlet, and jets the coolant from the jet outlet toward the sensor.

Effect of the Invention

[0007] According to the present disclosure, it is possible to provide an engine unit that can effectively cool a sensor that detects the rotational position of a rotor of a generator.

Brief Description of the Drawings

[0008]

Figure 1

Figure 2

Figure 3

Figure 4

Figure 5A

Figure 5B

Figure 6

Figure 7

Figure 8

Figure 9

Figure 10

DETAILED DESCRIPTION OF THE INVENTION

[0009] Hereinafter, embodiments will be described with reference to the drawings.

[0010] FIG. 1 is a left side view of a motorcycle 1 including an engine unit 11 according to an embodiment. The motorcycle 1 is an example of a saddle-riding vehicle on which a rider straddles and rides, and is a hybrid vehicle. The directions in the following description are based on the direction seen from the driver of the motorcycle 1. The front-rear direction corresponds to the vehicle length direction, and the left-right direction corresponds to the vehicle width direction.

[0011] The motorcycle 1 includes a front wheel 2, a rear wheel 3, a vehicle body frame 4, a front suspension 5 that connects the front wheel 2 to the front portion of the vehicle body frame 4, and a rear suspension 6 that connects the rear wheel 3 to the rear portion of the vehicle body frame 4. The front suspension 5 is connected to brackets 7 that are arranged at intervals in the vertical direction. A steering shaft connected to the brackets 7 is angularly displaceably supported by a head pipe 4a that is a part of the vehicle body frame 4. A handlebar 8 that the driver holds by hand is provided on the steering shaft. A fuel tank 9 is provided on the rear side of the handlebar 8, and a seat 10 on which the driver sits is provided on the rear side of the fuel tank 9.

[0012] A swing arm 15 that supports the rear wheel 3 and extends in the front-rear direction is angularly displaceably supported by the vehicle body frame 4. Further, an engine unit 11 that serves as a traveling drive source is mounted on the vehicle body frame 4 between the front wheel 2 and the rear wheel 3.

[0013] The engine unit 11 includes an engine E which is an internal combustion engine as a prime mover, and a drive motor M which is an electric motor as a prime mover. The engine E includes a cylinder Ea and a crankshaft Eb connected to a piston in the cylinder Ea. A balancer shaft B having a balancer weight is disposed on the front side of the crankshaft Eb. The balancer shaft B suppresses the primary couple vibration of the crankshaft Eb. A gear that rotates together with the crankshaft Eb and a gear that rotates together with the balancer shaft B are meshed with each other, and when the crankshaft Eb rotates, the balancer shaft B is rotationally driven.

[0014] The crankshaft Eb and the balancer shaft B of the engine E are accommodated in the crankcase 21. An oil pan 22 is provided at the lower part of the crankcase 21. The oil pan 22 stores oil that drops downward from the crank chamber in the crankcase 21 that accommodates the crankshaft Eb and the transmission 12. The crankshaft Eb and the balancer shaft B are parallel to each other and extend in the vehicle width direction of the motorcycle 1, that is, in the left-right direction. Also, a transmission 12 is disposed on the rear side of the engine E. The transmission 12 is accommodated in the crankcase 21.

[0015] FIG. 2 is a schematic diagram of the power train of the motorcycle 1 in FIG. 1. The transmission 12 has an input shaft 12a, an output shaft 12b, and a plurality of sets of gear trains 12c with different reduction ratios. The transmission 12 is configured to be able to transmit power from the input shaft 12a to the output shaft 12b via the gear train 12c, and selects any one of the gear trains 12c to shift gears. The input shaft 12a and the output shaft 12b are parallel to the crankshaft Eb and extend in the vehicle width direction of the motorcycle 1, that is, in the left-right direction. For example, the transmission 12 is a dog clutch type transmission. The rotational power of the output shaft 12b of the transmission 12 is transmitted to the rear wheel 3 which is a drive wheel via the output transmission member 16. The output transmission member 16 is, for example, a chain, a belt, or the like.

[0016] The right end of the crankshaft Eb of the engine E is connected to the primary gear 17 in a power-transmittable manner. The primary gear 17 is provided around the input shaft 12a between the main clutch 13 and the gear train 12c in the axial direction of the input shaft 12a. The primary gear 17 is rotatable relative to the input shaft 12a. The primary gear 17 transmits the rotational power from the crankshaft Eb to the main clutch 13. The primary gear 17 is connected to the input shaft 12a of the transmission 12 in a power-transmittable manner via the main clutch 13. The main clutch 13 is provided at the end of the input shaft 12a and disconnects and connects the power path from the crankshaft Eb to the input shaft 12a. The main clutch 13 is hydraulically driven. The main clutch 13 is, for example, a multi-plate clutch.

[0017] A sprocket 18, which is a rotating member that rotates together with the input shaft 12a around the input shaft 12a, is provided between the primary gear 17 and the gear train 12c. The drive motor M includes a motor housing Ma and a motor drive shaft Mb protruding from the motor housing Ma, and a sprocket 19 is provided on the motor drive shaft Mb so as to rotate together with the motor drive shaft Mb. Note that instead of the sprockets 18 and 19, a gear or a pulley may be used as the rotating member. A chain 20, which is a power transmission member, is connected to the sprocket 18 on the input shaft 12a side and the sprocket 19 on the motor drive shaft Mb side. Thereby, the driving force of the drive motor M is transmitted to the input shaft 12a via the sprocket 18.

[0018] The electronic control unit (hereinafter referred to as "ECU") 25 controls the engine E. Specifically, it controls the throttle device T, the fuel injection device F, and the ignition device I. Further, the ECU 25 controls the generator 30 described below as a starter motor based on the signal received from the sensor 40 described below, and starts the engine E.

[0019] A generator 30 is disposed at the left end portion of a crankshaft Eb of an engine E. The generator 30 includes a rotor 31 and a stator 32. The generator 30 generates electricity when the rotor 31 rotates. In the present embodiment, the generator 30 is an outer rotor type generator.

[0020] The rotor 31 has a substantially bottomed cylindrical shape that opens to the left. The rotor 31 has a bottom wall portion 31a and a peripheral wall portion 31b. The bottom wall portion 31a is substantially disc-shaped or substantially annular. The peripheral wall portion 31b is substantially cylindrical and is connected to the outer peripheral edge portion of the bottom wall portion 31a. The peripheral wall portion 31b protrudes leftward from the bottom wall portion 31a. The crankshaft Eb is fixed to the bottom wall portion 31a of the rotor 31, and the rotor 31 rotates together with the crankshaft Eb. The rotation centers of the rotor 31 and the crankshaft Eb coincide with the central axis of the peripheral wall portion 31b. Magnets are disposed on the peripheral wall portion 31b of the rotor 31. The stator 32 is disposed radially inward of the peripheral wall portion 31b of the rotor 31. The stator 32 and the peripheral wall portion 31b of the rotor 31 face each other in the radial direction.

[0021] FIG. 3 is a perspective view seen from the left front obliquely of the engine unit 11 of FIG. 1. The crankcase 21 is of an upper and lower split type. The crankcase 21 has an upper case portion 21a and a lower case portion 21b. The crankshaft Eb and the balancer shaft B are located on the same plane that divides the upper case portion 21a and the lower case portion 21b in the crankcase 21 (see also FIG. 4). The crankcase 21 is box-shaped, and the upper case portion 21a is disposed above the lower case portion 21b so as to cover the crankshaft Eb and the balancer shaft B set in the lower case portion 21b and is fixed to the lower case portion 21b.

[0022] The generator 30 is disposed outside the crankcase 21. Specifically, the left end portion of the crankshaft Eb protrudes outside the crankcase 21 from the left side wall 21c of the crankcase 21. The rotor 31 is fixed to the left end portion of the crankshaft Eb outside the crankcase 21. A cover 23 is attached to the left side wall 21c of the crankcase 21 so as to cover the generator 30 from the left.

[0023] The cover 23 is concave and open to the right. The left side wall 21c of the crankcase 21 and the cover 23 define an accommodation space S in which the generator 30 is accommodated. The stator 32 is fixed to the cover 23. More specifically, the stator 32 is fixed to the inner surface of the cover 23, which is the surface facing the accommodation space S. When the cover 23 is attached to the crankcase 21, the stator 32 is arranged so as to face the rotor 31 in the radial direction, more specifically, the peripheral wall portion 31b of the rotor 31.

[0024] FIG. 4 is a partially enlarged left side view of the engine unit 11 of FIG. 1 with the cover 23 removed. The left side wall 21c of the crankcase 21 that contacts the cover 23 has a contact surface 21d that is in surface contact with the peripheral edge portion of the cover 23. The contact surface 21d is annular when viewed from the left. The surface of the left side wall 21c facing the accommodation space S is formed in a concave shape. Among the outer surfaces of the left side wall 21c, the contact surface 21d is located further to the left than the other surfaces of the left side wall 21c. That is, in the present embodiment, the accommodation space S is formed by the concave portion of the left side wall 21c and the concave portion of the cover 23. However, the surface of the left side wall 21c facing the accommodation space S does not necessarily have to be formed in a concave shape.

[0025] The generator 30 is a so-called integrated starter generator (ISG) that also functions as a starter motor of the engine E. Near this generator 30, a sensor 40 for causing the generator 30 to function as a starter motor is arranged. The sensor 40 detects the rotational position of the rotor 31, that is, the rotation angle. In the present embodiment, the sensor 40 is a magnetic sensor utilizing the Hall effect, that is, a Hall sensor having a Hall IC. The sensor 40 is connected to the ECU 25 via a wiring. However, in the drawing, the wiring connected to the sensor 40 is omitted.

[0026] In the present embodiment, the sensor 40 is attached to the stator 32. The sensor 40 is arranged above the rotation center of the crankshaft Eb.

[0027] FIG. 5A is a side view of the stator 32 to which the sensor 40 is attached. FIG. 5B is a top view of the stator 32 to which the sensor 40 is attached. The stator 32 has a stator core 33. The stator core 33 has an annular base 33a and a plurality of tooth portions 33b that radially protrude from the base 33a. The plurality of tooth portions 33b are provided at intervals in the circumferential direction. The stator 32 is formed by winding a coil 34 around each tooth portion 33b of the stator core 33.

[0028] The sensor 40 is fixed to some of the plurality of tooth portions 33b. Specifically, the sensor 40 has a main body portion 41 and a plurality of engaging portions 42 that protrude rightward from the main body portion 41 and engage with the stator 32. The main body portion 41 is formed in an arc shape extending in the circumferential direction. More specifically, the main body portion 41 has an arc-shaped housing extending in the circumferential direction, and electronic components such as a Hall IC are housed in this housing. The upper surface of the main body portion 41 and the tip portion of the tooth portion 33b are generally on the same arc-shaped curve in a side view. The wiring extending from the ECU 25 is connected to the main body portion 41.

[0029] Each engaging portion 42 protrudes rightward from the main body portion 41 so as to be continuous with the upper surface of the main body portion 41 and fits between two adjacent tooth portions 33b. The portion of the engaging portion 42 that enters between the two tooth portions 33b is radially opposed to the peripheral wall portion 31b of the rotor 31 together with the stator 32. Hereinafter, the portion of the engaging portion 42 that enters between the two tooth portions 33b is referred to as an opposing portion 42a.

[0030] Returning to FIG. 4, the engine unit 11 includes a coolant flow path 50. The coolant flow path 50 has a jet outlet 50a, guides coolant for cooling the sensor 40 to the jet outlet 50a, and jets the coolant from the jet outlet 50a toward the sensor 40. The coolant flow path 50 includes a cover flow path 51 shown by a broken line in FIG. 4. The cover flow path 51 is formed in the cover 23. The jet outlet 50a is the downstream end portion in the cover flow path 51.

[0031] In this embodiment, for the coolant flow path 50, lubricating oil (hereinafter also referred to as "oil") for supplying the engine E and the transmission 12 in the crankcase 21 is used as the coolant. That is, the coolant flow path 50 and the lubricating oil flow path 60 are connected to each other. For example, the lubricating oil flow path 60 is a flow path of an existing engine unit. The lubricating oil flow path 60 is a flow path through which lubricating oil for lubricating a predetermined member such as a crankshaft housed in the crankcase flows. Referring to FIGS. 6 to 9, the flow of the oil used as the coolant will be described.

[0032] FIG. 6 is a block diagram showing the oil path of the engine unit 11 of FIG. 1. The oil stored in the oil pan 22 is sucked up by the oil pump 61 through the oil strainer and sucked into the oil pump 61. The oil pump 61 is housed in the crankcase 21. The engine E and the drive motor M are connected to the oil pump 61 so as to be able to transmit power. That is, the oil pump 61 is a mechanical type driven by the driving force of the engine E and the driving force of the drive motor M. However, the oil pump 61 may be an electric type.

[0033] FIG. 7 is a perspective view of the engine unit 11. In FIG. 7, the generator 30, the cover 23, etc. are omitted so that the left side wall 21c of the crankcase 21 and the lubricating oil flow path 60 in the crankcase 21 can be seen clearly. The oil discharged from the oil pump 61 is supplied to the oil filter 62 through the flow path 61a in the crankcase 21. The oil supplied to the oil filter 62 is filtered by the oil filter 62 and supplied to the main flow path 63 of the lubricating oil flow path 60 of the engine E.

[0034] The main flow path 63 extends in the left - right direction inside the crankcase 21. The main flow path 63 is integrally formed during the manufacture of the engine unit 11, for example, during the casting of the crankcase 21. More specifically, the main flow path 63 is formed so as to penetrate the left side wall 21c of the crankcase 21 by core - pulling during casting. For this reason, an opening 21ca that communicates with the main flow path 63 is formed in the left side wall 21c of the crankcase 21. The opening 21ca at the left end of the main flow path 63 is closed by a closing member 64 fixed to the left side wall 21c. The closing member 64 is, for example, a plug, a cap, or the like.

[0035] In addition, in the left side wall 21c of the crankcase 21, not only the opening 21ca for forming the main flow path 63 but also an opening 21cb for the crankshaft Eb and an opening 21cc for the balancer shaft B are formed. A bearing for the crankshaft Eb is arranged in the opening 21cb. The crankshaft - use opening 21cb allows the crankshaft Eb to pass through. A bearing for the balancer shaft B is arranged in the opening 21cc. The left end portion of the balancer shaft B is arranged in the opening 21cc for the balancer shaft. Note that the openings 21ca, 21cb, and 21cc may be formed by core - pulling or may be formed by another method such as drilling. Also, the openings 21ca, 21cb, and 21cc all open into the accommodation space S. That is, the openings 21ca, 21cb, and 21cc are arranged inside the annular contact surface 21d.

[0036] A plurality of crankshaft - use flow paths 65 that lead lubricating oil to the bearings supporting the crankshaft Eb branch off from the main flow path 63. Also, a balancer - shaft - use flow path 66 that leads lubricating oil to the bearings supporting the balancer shaft B branches off from the main flow path 63. The coolant flow path 50 guides the lubricating oil that has passed through the balancer - shaft - use flow path 66 to the sensor 40.

[0037] FIG. 8 is an enlarged partial cross-sectional view taken along a plane perpendicular to the front-rear direction of the engine unit 11 in FIG. 3. FIG. 9 is an enlarged partial perspective view showing the engine unit 11 in FIG. 3 in a partially cut-away state. A connecting member 24 is disposed in the accommodation space S. The connecting member 24 extends in the left-right direction. Note that the cross-sectional view in FIG. 8 is a view taken along a plane passing through the connecting member 24. The connecting member 24 is disposed on the front side of the crankshaft Eb. More specifically, the connecting member 24 is in the same position as the balancer shaft B in the front-rear direction and the up-down direction.

[0038] The connecting member 24 has a disk portion 24a that is substantially the same shape and size as the opening 21cc, and a cylindrical portion 24b that protrudes leftward from the central portion of the disk portion 24a toward the cover 23. The disk portion 24a is disposed in the opening 21cc so as to close the opening 21cc. The left end portion of the cylindrical portion 24b abuts against the inner surface of the cover 23. A connecting flow path 52 that penetrates the central portions of the disk portion 24a and the cylindrical portion 24b in the left-right direction is formed in the connecting member 24. The connecting flow path 52 extends linearly in the left-right direction. An inlet 51a of the cover flow path 51 opens on the inner surface of the cover 23, and the connecting flow path 52 connects the opening 21cc of the crankcase 21 and the inlet 51a of the cover flow path 51 in the accommodation space S.

[0039] The lubricating oil flows from the main flow path 63 through the flow path 66 for the balancer shaft and then flows into the connecting flow path 52 at the opening 21cc. The lubricating oil that has flowed through the connecting flow path 52 flows into the cover flow path 51 from the inlet 51a and is guided to the ejection port 50a.

[0040] The ejection port 50a is disposed above the rotation center of the crankshaft Eb. The ejection port 50a is located at a position that overlaps with the space between the upper surface of the sensor 40 and the inner peripheral surface of the rotor 31 facing the upper surface when viewed in the axial direction of the crankshaft Eb. Also, the ejection port 50a faces in the axial direction of the crankshaft Eb. The coolant flow path 50 ejects coolant in the axial direction of the crankshaft Eb toward the upper surface of the sensor 40 including the opposing portion 42a so that the coolant enters the space between the upper surface of the sensor 40 and the inner peripheral surface of the rotor 31 that face each other in the radial direction.

[0041] The flow cross-sectional area of the ejection port 50a is smaller than the flow cross-sectional area of the remaining portion of the cover flow path 51. For this reason, the flow velocity of the oil ejected from the ejection port 50a can be increased, and it is easy to enhance the effect of cooling the sensor while suppressing the ejected oil flow rate. Further, since the ejected oil flow rate is reduced, it is possible to prevent the oil from accumulating at the bottom of the accommodation space S and the accumulated oil from becoming a resistance to the rotation of the rotor 31.

[0042] The lubricating oil ejected from the ejection port 50a contacts the sensor 40 and cools the sensor 40. After contacting the sensor 40, the lubricating oil drops downward into the accommodation space S and accumulates at the bottom of the accommodation space S. A discharge port is provided at the bottom of the accommodation space S, and the oil discharged from the discharge port flows to the oil pan 22.

[0043] As described above, the engine unit 11 according to the present embodiment includes a coolant flow path 50 that guides the coolant to the ejection port 50a and ejects the coolant from the ejection port 50a toward the sensor 40. By ejecting the coolant from the ejection port 50a toward the sensor 40 to liquid-cool the sensor 40, it is easy to take away the heat of the sensor 40, and the sensor 40 can be effectively cooled.

[0044] Further, in the present embodiment, since the coolant flow path 50 ejects the coolant toward the opposing portion 42a of the sensor 40 that is radially opposed to the rotor 31, the coolant can be ejected aiming at the portion that is likely to increase in temperature due to the heat from the rotor 31.

[0045] Further, in the present embodiment, since the sensor 40 and the ejection port 50a are arranged above the rotation center of the crankshaft Eb, it is difficult for the sensor 40 to be immersed in the coolant accumulated in the lower part of the accommodation space S. Thereby, it is possible to prevent an abnormality from occurring in the sensor 40 due to immersion in water. Further, since the sensor 40 is arranged above the rotation center of the crankshaft Eb, when the ECU 25 is located above the rotation center of the crankshaft Eb, the wiring from the sensor 40 to the ECU 25 can be shortened.

[0046] Further, in the present embodiment, the coolant flow path 50 injects coolant toward the upper surface of the sensor 40. The coolant injected toward the upper surface of the sensor 40 flows downward along the side surface of the sensor 40 after passing along the upper surface of the sensor 40. Thereby, the surface area of the sensor 40 in contact with the coolant can be increased, and the cooling efficiency can be enhanced.

[0047] Further, in the present embodiment, the upper surface of the facing portion 42a of the sensor 40 faces the inner peripheral surface of the rotor 31 in the radial direction, and the coolant flow path 50 injects coolant in the axial direction of the crankshaft Eb toward the upper surface of the sensor 40 so that the coolant enters the space between the upper surface of the sensor 40 and the inner peripheral surface of the rotor 31 that face each other in the radial direction. Thereby, since the coolant advances in the axial direction along the upper surface of the sensor 40, the surface area of the sensor 40 in contact with the coolant can be increased.

[0048] Further, in the present embodiment, the cover 23 has a cover flow path 51 that is a part of the coolant flow path 50. Since the heat of the oil passing through the cover flow path 51 is taken away by the cover 23, the coolant is easily cooled.

[0049] Further, in the present embodiment, the lubricating oil flow path 60 provided in the crankcase and the coolant flow path 50 are connected to each other, and the coolant flow path 50 ejects lubricating oil as coolant toward the sensor 40. Therefore, it is not necessary to separately provide a tank for storing the coolant and a pump for supplying the coolant in the engine unit.

[0050] Further, in the present embodiment, the connecting member 24 is disposed in the accommodation space S. Therefore, even if lubricating oil leaks from the end portion of the connecting member 24, the leaked lubricating oil accumulates in the accommodation space S, and it is possible to prevent the lubricating oil from leaking to the outside of the accommodation space S.

[0051] Incidentally, through-holes for arranging a balancer shaft or the like are formed in the side walls of the crankcase of a conventional engine unit during the manufacture of the crankcase. These through-holes are blocked by a blocking member such as a plug or a cap to prevent lubricating oil from being discharged outside the crankcase through the through-holes. In the present embodiment, the opening 21cc formed during the manufacture of the crankcase 21 is used as a hole for guiding oil from the lubricating oil passage 60 to the coolant passage 50. For this reason, oil can flow into the coolant passage 50 without modifying the crankcase of the existing design.

[0052] <Other Embodiments> The present disclosure is not limited to the above-described embodiments, and its configuration can be changed, added, or deleted.

[0053] For example, in the above embodiment, oil is supplied from the lubricating oil passage 60 to the coolant passage 50 through the opening 21cc for the balancer shaft, but oil may be supplied from the lubricating oil passage 60 to the coolant passage 50 through the opening 21ca connected to the main passage 63. In this case, for example, at the opening 21ca shown in FIG. 7, instead of the blocking member 64, an end portion of a connecting member having a connecting passage formed therein may be arranged, and a blocking member may be arranged at the opening 21cc. The shape of the connecting member, the shape of the cover passage, and the arrangement of the inlet of the cover passage can be appropriately designed.

[0054] The coolant passage may not have a connecting passage connecting the opening in the side wall of the crankcase and the cover passage. That is, the lubricating oil passage and the cover passage as the coolant passage may be connected on the surface where the crankcase and the cover contact each other.

[0055] For example, FIG. 10 shows a cover 123 of an engine unit according to a modified example. The cover 123 has a cover flow path 150. The cover flow path 150 includes a plurality of branch paths between its inlet 151a and outlet 150a. Specifically, the cover flow path 150 includes an annular first flow path 151 along the annular contact surface of the cover 123 with respect to the crankcase, and a plurality of second flow paths 152 extending from a plurality of locations in the first flow path 151 to the outlet 150a respectively. Note that a flow path is formed in the crankcase which is connected to the inlet 151a of the cover flow path 150 and supplies oil to the inlet 151a. Thus, the oil path from the inlet 151a to the outlet 150a branches into a plurality of paths. By including a plurality of branch paths in the cover flow path 150, the surface area of the coolant can be increased, and the effect of cooling the coolant by the outside air contacting the cover 123 is enhanced.

[0056] Also, in the above embodiment, the generator 30 was arranged at the left end of the crankshaft Eb of the engine E, but the generator may be arranged at the right end of the crankshaft of the engine.

[0057] The injection position where the coolant is injected may be a position on the upstream side in the rotational direction of the rotor with respect to the sensor. In this case, as the rotor rotates, the coolant flows along the circumferential surface of the sensor to the downstream side in the rotational direction, and the coolant can be guided over a wide range with a small flow rate.

[0058] The sensor may not have a facing portion facing the rotor in the radial direction. For example, in the above embodiment, the sensor was fixed to the stator, but the sensor may not be fixed to the stator. The sensor may be fixed to the inner surface of the cover.

[0059] In the above embodiment, the sensor and the outlet were arranged above the rotation center of the crankshaft, but the sensor and the outlet may be arranged at the same height as the rotation center of the crankshaft, or may be arranged below the rotation center of the crankshaft.

[0060] In the above embodiment, the generator was an outer rotor type, but the generator may be an inner rotor type.

[0061] The coolant flow path does not have to inject coolant in the axial direction of the crankshaft, and may inject coolant in a direction intersecting the axial direction of the crankshaft.

[0062] The cover had a cover flow path that was part of the coolant flow path, but the cover does not have to have a part of the coolant flow path. For example, a flow path forming member that is a member different from the cover and the crankcase may be arranged in the accommodation space S, and the coolant flow path may be formed by the flow path forming member.

[0063] The coolant flow path and the lubricating oil flow path do not have to be connected to each other, and the coolant does not have to be lubricating oil. A tank for storing the coolant or a pump for supplying the coolant may be separately provided in the engine unit.

[0064] In the above embodiment, a Hall sensor having a Hall IC was exemplified as a sensor for detecting the rotation angle of the rotor, but the sensor for detecting the rotation angle of the rotor, that is, the sensor cooled by the coolant flow path, may be another type of sensor such as another type of magnetic sensor or a resolver type sensor.

[0065] In the above embodiment, the motorcycle was a hybrid vehicle, but it may be an engine vehicle having only an engine as a driving power source. That is, the engine unit does not have to include the drive motor M. Further, the saddle-riding vehicle including the engine unit is not limited to a motorcycle and may be a three-wheeled vehicle or the like.

[0066] An engine unit according to an aspect of the present disclosure includes a cylinder, a crankshaft connected to a piston in the cylinder, a crankcase that houses the crankshaft, a rotor that rotates together with the crankshaft, and a stator that faces the rotor, a generator that generates electricity when the rotor rotates, a sensor that detects the rotational position of the rotor, a coolant passage that has a jet outlet, guides coolant to the jet outlet, and jets the coolant from the jet outlet toward the sensor.

[0067] According to the above configuration, since the coolant is jetted from the jet outlet toward the sensor to liquid-cool the sensor, it is easy to take away the heat of the sensor, and the sensor can be effectively cooled.

[0068] In the above engine unit, the sensor may have an opposing portion that faces the rotor in the radial direction, and the coolant passage may jet the coolant from the jet outlet toward the opposing portion of the sensor. According to this configuration, since the coolant passage jets the coolant toward the opposing portion of the sensor that faces the rotor in the radial direction, the coolant can be jetted aiming at the portion that is likely to increase in temperature due to the heat from the rotor.

[0069] The above engine unit may further include a cover that covers the rotor and defines an accommodation space in which the rotor and the sensor are accommodated, and the sensor and the jet outlet may be disposed above the crankshaft. According to this configuration, it is difficult for the sensor to be immersed in the coolant accumulated in the lower part of the accommodation space. Thereby, it is possible to prevent sensor abnormalities due to water immersion.

[0070] In the above engine unit, the coolant passage may jet the coolant toward the upper surface of the sensor. According to this configuration, the coolant jetted toward the upper surface of the sensor flows downward along the side surface of the sensor after passing along the upper surface of the sensor. Thereby, the surface area of the sensor in contact with the coolant can be increased to improve the cooling efficiency.

[0071] In the above engine unit, the rotor is cylindrical, the crankshaft is annular, and at least a part of the upper surface of the sensor faces the inner peripheral surface of the rotor in the radial direction above the crankshaft. The coolant flow path may inject coolant in the axial direction of the crankshaft toward the upper surface of the sensor so that coolant enters the space between the upper surface of the sensor and the inner peripheral surface of the rotor that face each other in the radial direction. According to this configuration, since the coolant travels in the axial direction along the upper surface of the sensor, the surface area of the sensor in contact with the coolant can be increased.

[0072] The above engine unit further includes a cover that covers the rotor and defines an accommodation space in which the rotor and the sensor are accommodated, and the cover may have at least a part of the coolant flow path. According to this configuration, the coolant is easily cooled because heat is taken away by the cover.

[0073] In the above engine unit, the crankcase has a lubricating oil flow path through which lubricating oil for lubricating a predetermined member accommodated in the crankcase flows, the coolant flow path and the lubricating oil flow path are connected to each other, and the coolant flow path may eject the lubricating oil as coolant toward the sensor.

[0074] In the above engine unit, an end portion of the crankshaft protrudes from a side wall of the crankcase to the outside of the crankcase, the rotor is fixed to the end portion of the crankshaft outside the crankcase, the engine unit further includes a cover attached to the crankcase so as to cover the rotor, the cover has the coolant flow path, and the coolant flow path and the lubricating oil flow path may be connected at a surface where the crankcase and the cover contact each other. According to this configuration, since the lubricating oil directly flows from the lubricating oil flow path into the coolant flow path in the cover, a member for guiding the lubricating oil from the lubricating oil flow path to the coolant flow path in the cover is not required, and the number of parts can be reduced.

Description of Reference Numerals

[0075] 11: Engine unit 21: Crankcase 21c: Left side wall 21ca: Opening 21cb: Opening 21cc: Opening 21d: Contact surface 23: Cover 24: Connecting member 30: Generator 31: Rotor 32: Stator 40: Sensor 42a: Opposing part 50: Cooling liquid flow path 50a: Jet outlet 51: Cover flow path 51a: Inlet 52: Connecting flow path 60: Lubricating oil flow path 61: Oil pump 62: Oil filter 63: Main flow path 64: Blocking member 66: Flow path for balance shaft B: Balance shaft E: Engine Ea: Cylinder Eb: Crankshaft S: Accommodation space

Claims

1. A cylinder, a crankshaft connected to a piston within the cylinder, a crankcase that houses the crankshaft, a generator having a rotor that rotates with the crankshaft and a stator that faces the rotor, and that generates electricity when the rotor rotates, a sensor that detects the rotational position of the rotor, a coolant flow path having a jet outlet, guiding coolant to the jet outlet, and jetting the coolant from the jet outlet toward the sensor, and the rotor is cylindrical, at least a part of the upper surface of the sensor faces the inner peripheral surface of the rotor in the radial direction above the rotation center of the crankshaft, the coolant flow path jets coolant in the axial direction of the crankshaft toward the upper surface of the sensor so that coolant enters the space between the upper surface of the sensor and the inner peripheral surface of the rotor that face each other in the radial direction, an engine unit.

2. The sensor has a facing portion that faces the rotor in the radial direction, the coolant flow path jets coolant from the jet outlet toward the facing portion of the sensor, the engine unit according to claim 1.

3. The engine unit further includes a cover that covers the rotor and defines an accommodation space in which the rotor and the sensor are accommodated, the sensor and the jet outlet are disposed above the rotation center of the crankshaft, the engine unit according to claim 1 or 2.

4. The coolant flow path jets coolant toward the upper surface of the sensor, the engine unit according to any one of claims 1 to 3.

5. A cylinder, a crankshaft connected to a piston within the cylinder, a crankcase that houses the crankshaft, a generator having a rotor that rotates with the crankshaft and a stator that faces the rotor, and that generates electricity when the rotor rotates, a sensor that detects the rotational position of the rotor, a coolant flow path having a jet outlet, guiding coolant to the jet outlet, and jetting the coolant from the jet outlet toward the sensor, a cover that covers the rotor and defines an accommodation space in which the rotor and the sensor are accommodated, and the cover has at least a part of the coolant flow path, an engine unit.

6. The crankcase has a lubricating oil flow path through which lubricating oil for lubricating a predetermined member housed within the crankcase flows, The coolant flow path and the lubricating oil flow path are connected to each other, The coolant flow path sprays the lubricating oil as coolant toward the sensor, The engine unit according to any one of claims 1 to 5.

7. A cylinder, A crankshaft connected to a piston in the cylinder, A crankcase that houses the crankshaft, A generator having a rotor that rotates with the crankshaft and a stator facing the rotor, and generating electricity when the rotor rotates, A sensor that detects the rotational position of the rotor, An engine unit comprising: a coolant flow path having a jet outlet, guiding coolant to the jet outlet, and jetting the coolant from the jet outlet toward the sensor, The crankcase has a lubricating oil flow path through which lubricating oil for lubricating a predetermined member housed in the crankcase flows, The coolant flow path and the lubricating oil flow path are connected to each other, The coolant flow path jets the lubricating oil as coolant toward the sensor, An end portion of the crankshaft protrudes from a side wall of the crankcase to the outside of the crankcase, and the rotor is fixed to the end portion of the crankshaft outside the crankcase, The engine unit further includes a cover attached to the crankcase so as to cover the rotor, The cover has the coolant flow path, and the coolant flow path and the lubricating oil flow path are connected at a surface where the crankcase and the cover contact each other. Engine unit.

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