WO2018180015A1

WO2018180015A1 - Internal combustion engine

Info

Publication number: WO2018180015A1
Application number: PCT/JP2018/005957
Authority: WO
Inventors: 崇生岩▲崎▼; 博之内田; 拓哉藁品; 富幸佐々木
Original assignee: 本田技研工業株式会社
Priority date: 2017-03-30
Filing date: 2018-02-20
Publication date: 2018-10-04
Also published as: JP2018168826A; CN110462186A; CN110462186B; JP6487959B2

Abstract

An internal combustion engine (23) is provided with: a crankcase (24) accommodating a crankshaft (41) and a transmission gear shaft; and a rotation sensor (34) that is fixed to the crankcase (24) and that detects rotation fluctuation of the crankshaft (41) disposed inside the crankcase (24). On the front portion of the crankcase (24), a pair of upper and lower engine hanger bosses (29a, 29b) via which the crankcase (24) is supported by a vehicle body (12), are provided so as to extend forward. The rotation sensor (34) is disposed in a through hole (81) provided between the pair of upper and lower engine hanger bosses (29a, 29b). Accordingly, a structure for mounting a rotation sensor is provided which can protect the rotation sensor from a rock, etc. tossed up from a road surface.

Description

Internal combustion engine

The present invention relates to an internal combustion engine including a crankcase that houses a crankshaft and a transmission gear shaft, and a rotation sensor that is fixed to the crankcase and detects a rotational fluctuation of an internal crankshaft.

Patent Document 1 discloses an internal combustion engine. The crankshaft of the internal combustion engine protrudes from the crankcase and is connected to the clutch outer of the clutch via a reduction gear mechanism. The power of the crankshaft is transmitted from the clutch to the transmission gear shaft of the transmission. The clutch and reduction gear mechanism is covered with a clutch cover to which the crankshaft is coupled. A rotation sensor is fastened to the outer surface of the crankcase inside the clutch cover.

Japanese Unexamined Patent Publication No. 58-70058 Japanese Unexamined Patent Publication No. 2012-371906

Patent Document 2 discloses misfire detection of an internal combustion engine. In the misfire detection, it is required to detect the rotational fluctuation of the crankshaft with high accuracy. Since the rotation sensor is large in detecting accurate rotation fluctuation, it is difficult to fit such a rotation sensor inside the clutch cover. On the other hand, when the rotation sensor protrudes from the outer surface of the crankcase, it becomes a problem to improve reliability against disturbances such as stones that jump from the road surface.

The present invention has been made in view of the above circumstances, and an object of the present invention is to provide a rotation sensor mounting structure that can protect the rotation sensor from a stone that jumps up from a road surface.

According to a first aspect of the present invention, in the internal combustion engine comprising: a crankcase that houses the crankshaft and the transmission gear shaft; and a rotation sensor that is fixed to the crankcase and detects a rotation variation of the crankshaft inside. A pair of upper and lower engine hanger bosses for supporting the crankcase on the vehicle body is provided at the front of the crankcase and extends forward, and is provided between the pair of upper and lower engine hanger bosses in a side view of the vehicle body. An internal combustion engine in which the rotation sensor is disposed in a hole is provided.

According to the second aspect, in addition to the configuration of the first side surface, in the pair of upper and lower engine hanger bosses, the left and right sides and the front are covered by the engine hanger provided at the lower end of the down frame extending downward from the head pipe. .

According to the third aspect, in addition to the configuration of the second side, the pair of upper and lower engine hanger bosses are disposed on the inner side of the down frame and fastened to a protective member that covers the rotation sensor.

According to the fourth aspect, in addition to the configuration of the second or third aspect, the engine hanger is continuously integrated with the down frame.

According to the fifth aspect, in addition to the configuration of the fourth side surface, the through hole is arranged to be biased toward one of the engine hanger bosses, and the rotation sensor has a socket that opens toward the other in the axial direction. A gap that allows passage of the sensor cord is formed between the crankcase and the engine hanger on the other side in the axial direction.

According to the sixth aspect, in addition to the configuration of the fourth side, the sensor cord connected to the rotation sensor is guided upward in the down frame and connected to the control device.

According to the seventh aspect, in addition to the configuration of the fourth side surface, the rotation sensor includes a flange portion that is overlapped with a base formed on the crankcase and fastened to the crankcase with a bolt, A head is disposed opposite to the edge of the engine hanger.

According to the first aspect, the rotation sensor is protected from stones that jump from the road surface by using a pair of upper and lower engine hanger bosses.

According to the second aspect, the rotation sensor is protected by the body parts that are originally present. Dedicated protection components can be reduced.

According to the third aspect, the lower frame is reinforced with a protective member at the lower end. Moreover, the rotation sensor is double protected by the down frame and the protection member.

According to the fourth aspect, the number of parts is reduced and productivity is improved.

According to the fifth aspect, when the coupler of the sensor cord is fitted in the socket, the sensor cord can be pulled out from the gap defined between the front surface of the crankcase and the engine hanger. Therefore, the engine hanger can be separated from the internal combustion engine while the sensor cord is connected to the rotation sensor. Good maintainability is ensured.

¡According to the sixth aspect, the sensor cord is protected by the down frame. The down frame improves the noise resistance of the sensor cord.

According to the seventh aspect, the bolt can be visually recognized from the gap between the crankcase and the engine hanger. In this way, the installation of the bolt can be confirmed. Moreover, the engine hanger can function as a bolt stopper.

FIG. 1 is a side view schematically showing an entire configuration of a motorcycle. FIG. 2 is an enlarged partial sectional view of the motorcycle schematically showing the structure of the internal combustion engine. FIG. 3 is an enlarged partial sectional view of the internal combustion engine schematically showing the structure of the internal combustion engine. FIG. 4 is an enlarged cross-sectional view taken along line 4-4 of FIG. FIG. 5 is an enlarged side view of a motorcycle schematically showing the arrangement of sensor cords according to one specific example. FIG. 6 is an enlarged side view of a motorcycle schematically showing the arrangement of sensor cords according to another specific example.

11 ... saddle riding type vehicle (motorcycle)
12 ... Body (body frame)
12b ... down frame 12d ... engine hanger 13 ... head pipe 23 ... internal combustion engine 24 ... crankcase 29a ... engine hanger boss 29b ... engine hanger boss 33 ... control device 34 ... rotation sensor 41 ... crankshaft 57 ... transmission gear shaft (input shaft) )
58 ... Transmission gear shaft (output shaft)
81 ... Through-hole 83 ... Protection member 88 ... Socket 89 ... Sensor cord 92 ... Gap 93 ... Base 94 ... Bolt 95 ... Flange

Hereinafter, an embodiment of the present invention will be described with reference to the accompanying drawings. Here, the top, bottom, front, back, left and right of the vehicle body are defined based on the eyes of the occupant riding the motorcycle.

FIG. 1 schematically shows the overall configuration of a motorcycle according to an embodiment of the present invention. The motorcycle 11 includes a body frame 12. The vehicle body frame 12 includes a pair of left and right main frames 12a extending downward from the head pipe 13, a pivot frame 12c extending downward from the lower end of the main frame 12a, and a lower portion of the main frame 12a below the head pipe 13. Down frame 12b extending toward the bottom, and engine hanger 12d coupled to the lower end of down frame 12b. The engine hanger 12d is continuously integrated from the lower end of the down frame 12b.

A front fork 14 is supported on the head pipe 13 so as to be steerable. A front wheel WF is supported on the front fork 14 so as to be rotatable around the axle 15. A handle bar 16 is coupled to the front fork 14 above the head pipe 13. On the rear side of the vehicle body frame 12, a swing arm 18 is supported on the pivot frame 12c so as to be swingable around a support shaft 19 extending horizontally in the vehicle width direction. A rear wheel WR is supported at the rear end of the swing arm 18 so as to be rotatable around the axle 21.

An internal combustion engine 23 is mounted on the body frame 12 between the front wheel WF and the rear wheel WR. The internal combustion engine 23 includes a crankcase 24, a cylinder block 25 coupled to the crankcase 24 and extending upward from the crankcase 24, a cylinder head 26 coupled to the cylinder block 25, and a head cover coupled to the cylinder head 26. 27. The crankcase 24 accommodates a crankshaft 41 (described later) that rotates around a rotation axis 28 that extends parallel to the axle 21 of the rear wheel WR. The rotational motion of the crankshaft 41 is transmitted to the rear wheel WR via a transmission device (not shown). A pair of upper and lower

engine hanger bosses

29a and 29b extending forward and connected to the engine hanger 12d are provided on the front surface of the crankcase 24. On the rear surface of the crankcase 24, a pair of upper and lower

engine hanger bosses

29c and 29d connected to the pivot frame 12c are provided. The crankcase 24 is connected to and supported by the vehicle body frame 12 by engine hanger bosses 29a to 29d.

A fuel tank 31 is mounted on the vehicle body frame 12 above the internal combustion engine 23. An occupant seat 32 is mounted on the vehicle body frame 12 behind the fuel tank 31. Fuel is supplied from the fuel tank 31 to the fuel injection device of the internal combustion engine 23. When driving the motorcycle 11, the occupant straddles the occupant seat 32.

A control device 33 is supported on the vehicle body frame 12 below the fuel tank 31. A rotation sensor (pulser sensor) 34 is attached to the front surface of the crankcase 24 between a pair of upper and lower

engine hanger bosses

29a and 29b. As will be described later, the rotation sensor 34 is connected to the control device 33 by wire. The rotation sensor 34 detects the angular velocity of the crankshaft 41. The control device 33 detects misfire of the internal combustion engine 23 according to the fluctuation of the angular velocity.

2, the internal combustion engine 23 includes a piston 36 incorporated in the cylinder block 25. The piston 36 is accommodated in a cylinder 37 having a cylinder axis inclined forward and defined in the cylinder block 25. Here, the cylinder block 25 is formed with a single cylinder 37 for receiving a single piston 36. A combustion chamber 38 is defined between the piston 36 and the cylinder head 26.

One end of a connecting rod 39 is connected to the piston 36. The other end of the connecting rod 39 is connected to the crankshaft 41 in the crankcase 24. The linear motion of the piston 36 in the axial direction is converted into rotational motion of the crankshaft 41 by the action of the connecting rod 39.

As shown in FIG. 3, the crankshaft 41 includes

journals

41a and 41b coupled to bearings 42 and 43 so as to be rotatable around an axis. The axes of the

journals

41 a and 41 b coincide with the rotation axis 28. The outer rings of the bearings 42 and 43 are fitted into the crankcase 24. The

journals

41a and 41b are fitted into the inner rings of the bearings 42 and 43, respectively. A plurality of balls are arranged between the outer ring and the inner ring.

The crankshaft 41 has a first drive shaft 44 that protrudes outward from the crankcase 24 in one direction, and a second drive shaft 45 that protrudes outward from the crankcase 24 in the other direction. An ACG (alternator) starter 47 is connected to the first drive shaft 44. The ACG starter 47 includes a rotor 48 and a stator 49. The rotor 48 is coupled to the first drive shaft 44 protruding from the crankcase 24 so as not to be relatively rotatable. The rotor 48 has a plurality of magnets 51 arranged in the circumferential direction. The rotor 48 surrounds the outer periphery of the stator 49. A plurality of coils 52 arranged in the circumferential direction are wound around the stator 49. The coil 52 follows a trajectory facing the trajectory of the magnet 51 when the rotor 48 rotates. The ACG starter 47 functions as a starter motor that automatically starts the crankshaft 41 when the internal combustion engine 23 is started. When the start of the internal combustion engine 23 is confirmed, the ACG starter 47 functions as an AC generator.

A case cover 53 is coupled to the outer surface of the crankcase 24. A space for accommodating the valve mechanism is defined between the case cover 53 and the crankcase 24. The stator 49 is supported by the case cover 53. A generator cover 54 is coupled to the case cover 53. The rotor 48 and the stator 49 are accommodated in a space defined by the generator cover 54 and the case cover 53.

A dog clutch type multi-stage transmission 56 is incorporated in the internal combustion engine 23. The multi-stage transmission 56 is accommodated in the crankcase 24. The multi-stage transmission 56 includes an input shaft 57 and an output shaft 58 having an axis parallel to the axis of the crankshaft 41. The input shaft 57 and the output shaft 58 are rotatably supported by the crankcase 24 with bearings. The input shaft 57 is connected to the crankshaft 41 through the primary reduction mechanism 59. The primary reduction mechanism 59 includes a power transmission gear 61 that is coupled to the second drive shaft 45 of the crankshaft 41 so as not to be relatively rotatable, and a driven gear 62 that is supported on the output shaft 58 so as to be relatively rotatable. The driven gear 62 meshes with the power transmission gear 61.

The output shaft 58 is coupled with a drive sprocket 63 of the transmission. A drive chain 64 is wound around the drive sprocket 63. The drive chain 64 transmits the rotational power of the drive sprocket 63 to the rear wheel WR.

４ Four drive gears are arranged on the input shaft 57. The drive gear includes a low drive gear 65, a fourth speed drive gear 66, a third speed drive gear 67, a fifth speed drive gear 68 and a second speed drive gear 69 in order. Similarly, four driven gears are arranged on the output shaft 58 in order. The driven gear includes a low driven gear 71, a fourth speed driven gear 72, a third speed driven gear 73, a fifth speed driven gear 74 and a second speed driven gear 75. In the multi-stage transmission 56, the coupling state is selectively switched between the neutral state, the first speed coupling state, the second speed coupling state, the third speed coupling state, the fourth speed coupling state, and the fifth speed coupling state.

A friction clutch 76 is incorporated in the internal combustion engine 23. The friction clutch 76 includes an outer clutch 76a and a clutch hub 76b. The driven gear 62 of the primary reduction mechanism 59 is connected to the clutch outer 76a. According to the operation of the clutch lever, the friction clutch 76 is switched between connection and disconnection between the clutch outer 76a and the clutch hub 76b.

The internal combustion engine 23 includes an annular plate-shaped pulsar ring (detected body) 78 that is coupled to the crankshaft 41 coaxially with the rotation axis 28 and rotates integrally with the crankshaft 41. The pulsar ring 78 is disposed between the crank web 41 c of the crankshaft 41 and the bearing 42. The pulsar ring 78 is sandwiched and fixed between the crank web 41c and the inner ring of the bearing 42. Thus, the pulsar ring 78 is fixed in the axial direction of the crankshaft 41.

The pulsar ring 78 includes a standing piece 78a that is partially cut and raised from the annular plate. The standing piece 78a is received in a recess 79 formed on the side surface of the crank web 41c. The standing piece 78a engages with the recess 79 to prevent relative rotation about the rotation axis 28 between the pulsar ring 78 and the crank web 41c.

As shown in FIG. 2, the rotation sensor 34 is disposed in a through hole 81 provided in the front surface 24b of the crankcase 24 between a pair of upper and lower

engine hanger bosses

29a, 29b. The rotation sensor 34 is inserted into the through hole 81 from the outside. The rotation sensor 34 faces the crank chamber 24a at the tip that detects the magnetic material. The tip of the rotation sensor 34 faces the annular track of the pulsar ring 78. The rotation sensor 34 generates a pulse signal according to the movement of the pulsar ring 78.

The pulsar ring 78 includes a plurality of retractors 78b arranged around the rotation axis 28 in an annular manner at equal intervals. For example, the retractor 78b is arranged at every central angle of 10 degrees. The retractor 78b is made of, for example, a magnetic material.

In the rotation sensor 34, the detection axis 34a having the highest sensitivity is directed to the rotation axis 28. The detection axis 34 a is orthogonal to the rotation axis 28. The rotation sensor 34 outputs an electrical signal according to the presence or absence of a magnetic material detected on the orbit of the pulsar ring 78. The rotation sensor 34 outputs a pulse signal that specifies the angular position of the crankshaft 41.

Referring also to FIG. 4, the engine hanger 12d includes a pair of side plates 82a sandwiching a pair of upper and lower

engine hanger bosses

29a and 29b in the horizontal direction, and a pair of upper and lower engine hanger bosses connected to each other. It includes a front plate 82b disposed in front of 29a and 29b. A protective member 83 is sandwiched between the

engine hanger bosses

29a and 29b and the engine hanger 12d. The protective member 83 is disposed between the pair of upper and lower

engine hanger bosses

29a and 29b and the side plate 82a, and is connected to the inner surface of the side plate 82a and fixed to the first plate 83a. And a second plate 83b facing the pair of upper and lower

engine hanger bosses

29a and 29b between the pair of

engine hanger bosses

29a and 29b and the front wall 82b.

A boss hole 84 penetrating in the horizontal direction is formed in each of the

engine hanger bosses

29a and 29b. The first plate 83a of the protection member 83 is overlaid on the vertical surface 85 including the opening of the boss hole 84 and orthogonal to the axis 84a of the boss hole 84. A bolt 86 inserted into the boss hole 84 is coupled to the nut 87, and the engine hanger 12d and the protection member 83 are fixed to the

engine hanger bosses

29a and 29b.

The through hole 81 of the rotation sensor 34 is arranged to be biased toward the one side plate 82a in the axial direction of the

engine hanger bosses

29a and 29b. The rotation sensor 34 is provided with a socket 88 that opens toward the other side plate 82a. Coupler 91 of sensor cord 89 is coupled to socket 88. The coupler 91 is inserted into the socket 88 in parallel with the axis of the

engine hanger bosses

29a and 29b. A sensor cord 89 extends from the coupler 91 toward the other side plate 82a. A gap 92 that allows passage of the sensor cord 89 is formed between the front surface 24b of the crankcase 24 and the other side plate 82a.

The rotation sensor 34 has a flange portion 95 that is overlapped with a pedestal 93 formed on the crankcase 24 and fastened to the crankcase 24 with bolts 94. The edge of the side plate 82 a faces the head of the bolt 94.

As shown in FIG. 5, the sensor cord 89 is pulled out from the gap 92 between the side plate 82 a and the crankcase 24 and travels along the upper surface of the crankcase 24. The sensor cord 89 is connected to the control device 33 through the main frame 12a. The control device 33 receives the output signal of the rotation sensor 34. The angular speed of the crankshaft 41 is specified by the output signal. The control device 33 detects misfire of the internal combustion engine 23 according to the output signal.

Next, the operation of this embodiment will be described. The internal combustion engine according to this embodiment includes a crankshaft 41 rotatably supported by the crankcase 24, a detected body (pulsar ring 78) that rotates integrally with the crankshaft 41, and a front side from the front surface 24b of the crankcase 24. And a pair of

engine hanger bosses

29a and 29b connected to the vehicle body frame 12, and a rotation sensor 34 attached to the crankcase 24 from the outside between the

engine hanger bosses

29a and 29b. In other words,

engine hanger bosses

29a and 29b for supporting the crankcase 24 on the vehicle body frame 12 are provided at the front portion of the crankcase 24 so as to extend forward as a pair, and the upper and lower pairs of

engine hanger bosses

29a and 29b. The rotation sensor 34 is disposed in the through hole 81 provided therebetween. In the storage space of the crankcase 24, the arrangement structure is limited by the gear shafts (input shaft 57 and output shaft 58) of the multi-stage transmission 56. Since the rotation sensor 34 is attached from the outside of the crankcase 24, the rotation sensor 34 is disposed without interfering with the input shaft 57 and the output shaft 58. An increase in the size of the crankcase 24 and the case cover is avoided. Moreover, the rotation sensor 34 is protected from stones and the like jumping up from the road surface by using the pair of upper and lower

engine hanger bosses

29a and 29b. Boss holes 84 that penetrate in the horizontal direction are formed in the

engine hanger bosses

29a and 29b. The

engine hanger bosses

29a and 29b form a convex surface on the outer surface of the crankcase 24 over the entire length in the horizontal direction.

An engine hanger 12d is provided at the lower end of the down frame 12b extending downward from the head pipe 13. The engine hanger 12d is connected to the crankcase 24, and is connected to the pair of side plates 82a sandwiching the pair of upper and lower

engine hanger bosses

29a and 29b in the horizontal direction, and the pair of upper and lower engine hanger bosses 29a. , 29b, and a front plate 82b disposed in front of 29b. In the pair of upper and lower

engine hanger bosses

29a and 29b, the left and right sides and the front are covered by a part of the engine hanger 12d provided at the lower end of the down frame 12b extending downward from the head pipe 13. In this way, the rotation sensor 34 is protected by the originally existing vehicle body parts. Dedicated protective parts are omitted. However, since the engine hanger 12d is continuously integrated with the down frame 12b, the number of parts is reduced and the productivity is improved.

The protective member 83 is disposed between the pair of upper and lower

engine hanger bosses

29a, 29b and the side plate 82a, and connects the first plate 83a and the first plate 83a, which is overlapped and fixed to the inner surface of the side plate 82a. And a pair of upper and lower

engine hanger bosses

29a, 29b and a front plate 24b of the crankcase 24, and a second plate 83b facing the pair of upper and lower

engine hanger bosses

29a, 29b. Thus, the pair of upper and lower

engine hanger bosses

29a and 29b is coupled with a protective member 83 disposed inside the down frame 12b and covering the rotation sensor 34. The lower end of the down frame 12b is reinforced by a protective member 83. In addition, the rotation sensor 34 is doubly protected by the down frame 12 b and the protection member 83.

In the internal combustion engine 23, the through hole 81 is arranged in a biased manner toward the one side plate 82a in the axial direction of the

engine hanger bosses

29a and 29b. The rotation sensor 34 is provided with a socket 88 that opens toward the other side plate 82a. A gap 92 that allows passage of the sensor cord 89 is formed between the front surface 24b of the crankcase 24 and the other side plate 82a. When the coupler 91 of the sensor cord 89 is fitted into the socket 88, the sensor cord 89 can be pulled out from the gap 92 defined between the front surface 24b of the crankcase 24 and the side plate 82a. Therefore, the engine hanger 12 d can be separated from the internal combustion engine 23 while the sensor cord 89 is connected to the rotation sensor 34. Good maintainability is ensured.

In this embodiment, the rotation sensor 34 includes a flange portion 95 that is overlapped with a pedestal 93 formed on the crankcase 24 and fastened to the crankcase 24 with a bolt 94. The edge of the side plate 82a is disposed opposite to the head of the bolt 94. The bolt 94 is visually recognized from the gap 92 between the crankcase 24 and the engine hanger 12d. Thus, the attachment of the bolt 94 can be confirmed. Moreover, the engine hanger 12d can function as a retaining bolt 94.

In addition, as shown in FIG. 6, the sensor cord 89 may be guided upward in the down frame 12 b and connected to the control device 33 without being pulled out from the gap 92. In this case, the sensor cord 89 is protected by the down frame 12b. The down frame 12b improves the noise resistance of the sensor cord 89.

Claims

An internal combustion engine comprising a crankcase (24) that houses a crankshaft (41) and a rotation sensor (34) that is fixed to the crankcase (24) and detects rotational fluctuations of the crankshaft (41) inside. 23)
Engine hanger bosses (29a, 29b) for supporting the crankcase (24) on the vehicle body (12) are provided at the front portion of the crankcase (24) so as to extend forward as a pair, and in a side view of the vehicle body An internal combustion engine characterized in that the rotation sensor (34) is disposed in a through hole (81) provided between the pair of upper and lower engine hanger bosses (29a, 29b).
The internal combustion engine according to claim 1, wherein the pair of upper and lower engine hanger bosses (29a, 29b) is provided by an engine hanger (12d) provided at a lower end of a down frame (12b) extending downward from the head pipe (13). An internal combustion engine characterized in that the left and right sides and the front are covered.
The internal combustion engine according to claim 2, wherein the pair of upper and lower engine hanger bosses (29a, 29b) are disposed inside the down frame (12b) and cover the rotation sensor (34). An internal combustion engine that is fastened to the engine.
The internal combustion engine according to claim 2 or 3, wherein the engine hanger (12d) is continuously integrated with the down frame (12b).
5. The internal combustion engine according to claim 4, wherein the through hole (81) is arranged so as to be biased toward one side in an axial direction of the engine hanger boss (29 a, 29 b), and the rotation sensor (34) is arranged in the axial direction. A socket (88) opening toward the other side is provided, and a gap (allowing passage of a sensor cord (89) between the crankcase (24) and the engine hanger (12d) on the other side in the axial direction ( 92).
5. The internal combustion engine according to claim 4, wherein a sensor cord (89) connected to the rotation sensor (34) is guided upward in the down frame (12b) and connected to a control device (33). An internal combustion engine.
5. The internal combustion engine according to claim 4, wherein the rotation sensor (34) is overlaid on a pedestal (93) formed on the crankcase (24) and fastened to the crankcase (24) with a bolt (94). An internal combustion engine having a flange portion (95) having a head portion of the bolt (94) opposed to an edge portion of the engine hanger (12d).