1. Field of the Invention
The present invention generally relates to a signal detector of an engine for a vehicle, and particularly relates to the signal detector which is suitable for the engine for a two-wheeled motor vehicle having a starter.
2. Description of the Related Art
In an engine for a two-wheeled motor vehicle, it is preferable to mount a one-way clutch for a starter mechanism on a crankshaft in order to reduce a mechanical loss of power for starting the engine. Therefore, the one-way clutch is generally mounted on an end of the crankshaft. In addition to the one-way clutch, a generator rotor, a pulser rotor for outputting pulse signals for ignition signals, and the like, a sprocket for cam drive, and so on, are mounted on ends of the crankshaft, separately.
As one example of common arrangement, the sprocket for cam drive is mounted on one end of the crankshaft, and the generator is mounted on the other end of the crankshaft, where the one-way clutch for the starter mechanism is mounted in juxtaposition with the generator on the other end.
According to the arrangement in which the generator and the one-way clutch are mounted in juxtaposition with each other on the other end of the crankshaft longitudinally, however, the generator projects outwardly in the longitudinal direction, and therefore it is necessary to increase width of the crankcase (namely, length of the crankshaft). Particularly, if the two-wheeled motor vehicle is equipped with a plurality of cylinders (for example, four cylinders) in juxtaposition in the direction of the crankshaft, and if the generator projects outwardly in the longitudinal direction, it is not possible to take a large angle of bank.
There has also been provided an engine, as shown in
Also in the arrangement in which the one-way clutch 102 is mounted on the one end of the crankshaft 105 opposite the other end thereof on which the generator 103 is mounted as shown in
Therefore, it is an object of the present invention to provide a signal detector of an engine for a vehicle which makes the crankcase compact in the longitudinal direction of the crankshaft and reduces the number of assembling parts for the signal detector such as a signal detector for detecting ignition signals.
In accomplishing this and other objects of the present invention, there is provided a signal detector of an engine for a vehicle, in which the engine has a one-way clutch, for a starter mechanism of the engine, which is mounted on one end of a crankshaft of the engine, the signal detector comprising: a clutch outer member of the one-way clutch; and a sensor for detecting signals, in which the sensor is provided radially outside a cylindrical outer wall of the clutch outer member so as to be opposed to the cylindrical outer wall, wherein the cylindrical outer wall of the clutch outer member has: an outer surface of concavity and convexity as a signal output part which is detected by the sensor; and an annular reinforced part which is thicker than a bottom surface of the concavity of the signal output part.
According to the construction, the signal output part for outputting pulse signals for an ignition system, and the like, is directly formed on the cylindrical outer wall of the clutch outer member. Therefore, there is no need of providing a separate, or independent, additional rotational member for the exclusive use of outputting the signals like the conventional pulse rotor mounted on the crankshaft. That is, with the construction, it is possible to reduce the total number of assembling parts for the signal detector, to reduce the weight of parts which are mounted on the crankshaft of the engine, and to downsize the crankcase of the engine in the direction in which the crankshaft extends.
Also, according to the construction, since the signal output part is formed on the outer surface of the clutch outer member, it is possible to make width of the signal output part larger than that of the conventional disk-shaped pulser rotor. Thereby, the ability and performance to detect the signals is enhanced, and the leak of detection of the signals is effectively prevented.
When the clutch is engaged, a load is exerted outwardly upon the cylindrical outer wall of the clutch outer member by a clutch element (or clutch component) which is arranged inside the cylindrical outer wall. According to the construction, since the cylindrical outer wall of the clutch has the annular reinforced part which is formed thicker than the bottom surface of the concavity of the signal output part, the rigidity (or stiffness) of the cylindrical outer wall of the clutch outer member is maintained. Namely, with the construction, the deformation of the cylindrical outer wall is lessened upon the clutch engagement, and the performance of the one-way clutch is maintained.
In the construction, preferably, the annular reinforced part is provided on an open side of the cylindrical outer wall of the clutch outer member.
Namely, a part of the cylindrical outer wall of the clutch outer member which is the easiest to deform by the load exerted with the clutch member, is the open side of the cylindrical outer wall. According to the construction, since the open side of the cylindrical outer wall is provided with the annular reinforced part, such a deformation of the cylindrical outer wall is effectively reduced and suppressed.
In the construction, preferably, the sensor and a supporter for supporting a wire lead for the sensor are mounted on one of a crankcase of the engine and a cover mounted on the crankcase for the starter mechanism.
According to the construction, there is no trouble of arranging the wire lead(s) for the sensor when the cover is attached to, or removed from, the crankcase, in comparison with the conventional construction in which the sensor and the supporter are mounted to the crankcase and the cover, separately. Namely, with the construction, the assemblage and maintenance thereof becomes easy.
This and other objects and features of the present invention will become clear from the following description taken in conjunction with a preferred embodiment thereof with reference to the accompanying drawings.
Before a description of a preferred embodiment of the present invention proceeds, it is to be noted that like or corresponding parts are designated by like reference numerals throughout the accompanying drawings.
First, with reference to
Namely, as shown in
A cam-chain chamber 9 is formed on one side (namely, right side in
Meanwhile, a generator cover 15 is mounted on the other side (namely, left side in
Hereinafter, the “longitudinal direction of the crankshaft 5” is also referred to as “crankshaft longitudinal direction”, the “one side” of the crankcase 1 is also referred to as “right side”, and the “other side” of the crankcase 1 is also referred to as “left side”, for simplicity and convenience. Incidentally, the “one side” and the “left side” correspond to those, respectively, viewed from a rider of the two-wheeled motor vehicle, as shown in
As shown in the figure, the one end of the crankshaft 5 projects so as to pass through the cam-chain chamber 9 and extends up to the inside of the starter chamber 13. A sprocket 23 for driving the cam shaft 6 is integrally formed with a part of the crankshaft 5, the part being inside the cam-chain chamber 9. A cam-chain 24 extends between the sprocket 23 and a sprocket 26 which is fixed to the cam shaft 6 for driving the intake and exhaust valves, so as to be wound around both of the sprockets 23 and 26, where the cam-chain 24 passes through the cam-chain chamber 9 inside the crankcase 1, and through a cam-chain chamber 25 of the cylinder 2 and cylinder head 3.
Inside the starter chamber 13, a one-way clutch 30 for the starter mechanism 10 and a starter gear 31 are mounted on the one end of the crankshaft 5. Above the starter gear 31, there are arranged a first idler gear 34, a second idler gear 35, and an output pinion gear 37 of a starter motor 36 which is mounted on the crankcase 1, in this order. That is, the one-way clutch 30, the starter gear 31, the first idler gear 34, the second idler gear 35, the output pinion gear 37, and the starter motor 36 form the starter mechanism 10. There is also arranged a sensor 40 for detecting pulse signals for ignition system, radially outside the one-way clutch 30, as a signal detector for detecting the pulse signals. As the sensor 40, a magnetic sensor such as a pulser coil, etc. is employed in the embodiment. Alternatively, it is also possible to employ another type of sensor, such as an optical sensor making use of a light-receiving element, a sensor making use of sounds, and so on.
A small diametric part 36a, as an output side, of the starter motor 36 engages with a boss part 60 of the first cover 11, through an O-ring 57. The second idler gear 35 has a small diametric gear 35a and a large diametric gear 35b integrally. The second idler gear 35 is rotatably supported on the second idler shaft 52. The large diametric gear 35b meshes with an output pinion gear 37 of the starter motor 36. The first idler gear 34 also has a small diametric gear 35a and a large diametric gear 34b integrally. The first idler gear 34 is rotatably supported on the first idler shaft 51. The large diametric gear 34b meshes with the small diametric gear 35a of the second idler gear 35, and the small diametric gear 34a meshes with the starter gear 31. As shown in
The one-way clutch 30 which is mounted on the right side of the crankshaft 5, has a clutch outer member 62 which is cylindrical in shape and has a bottom, a clutch inner member 63 which is cylindrical in shape, and a clutch member 64 such as a sprag.
The clutch outer member 62 has an end wall part 62b as the bottom which is disk-shaped, an outer peripheral wall 62a which extends rightward from an outer periphery of the end wall part 62b to be cylindrical in shape, and an inner boss part 62c which extends rightward from an inner periphery of the end wall part 62b to be cylindrical in shape, integrally. The clutch outer member 62 locates on the right side of the sprocket 23 (namely, on the outer side in the crankshaft longitudinal direction), in which the inner boss part 62c spline-engages with the crankshaft such that the inner boss part 62c all the time rotates together with the crankshaft 5.
The clutch inner member 63 is opposed to an inner surface of the outer peripheral wall 62a of the clutch outer member 62 with a radially predetermined gap between an outer surface of the clutch inner member 63 and the inner surface of the clutch outer member 62, in which an inner peripheral surface of the clutch inner member 63 rotatably engages with an outer peripheral surface of the inner boss part 62c through a needle bearing 65.
The clutch member 64 is mounted between the outer surface of the clutch inner member 63 and the inner surface of the outer peripheral wall 62a of the clutch outer member 62. The clutch member 64 opens radially when the clutch inner member 63 rotates in a direction of a positive rotation of the engine, such that the clutch outer member 62 and the clutch inner member 63 are connected to each other. Namely, when the engine is started, a driving power for starting the engine in the direction of the positive rotation of the engine is transmitted from the clutch inner member 63 to the clutch outer member 62 (namely, to the crankshaft 5) only. The clutch inner member 63, and the inner boss part 62c of the clutch outer member 62, are locked to the crankshaft 5 with a retaining bolt 67 which is screwed into the right end of the crankshaft 5 through a retaining washer 68 such that the clutch outer member 62 and the clutch inner member 63 are immovable with respect to the crankshaft 5 in the crankshaft longitudinal direction.
The right end of the clutch inner member 63 extends beyond the right end of the outer peripheral wall 62a (namely, extends towards the outer part of the crankshaft 5), and the aforementioned starter gear 31 is integrally formed with the right end of the clutch inner member 63. Namely, the starter gear 31 is arranged on the right side of the clutch outer member 62, as shown in
As shown in
As shown in
With reference to
While the engine is working, the sensor 40 outputs pulse signals by sensing positions of the signal output teeth 71 on the outer peripheral wall 62a which rotates along with the crankshaft 5. The pulse signals are transmitted to a controller through the wire leads 76, and the pulse signals are processed by the controller in order to control the ignition timing for each cylinder of the engine.
Although the signal detector in the embodiment is used for the purpose of detecting the ignition signals, the pulse signals from the signal detector can be used for another purpose such as fuel injection signals by modifying the clutch outer member 62 such that the signal output teeth 71 have different shape (or profile) and arrangement (or configuration). It is also possible to use the same for another purpose such as that to detect the compression stroke and/or expansion stroke of the engine.
As shown in
The signal output teeth 71 are formed on the outer peripheral wall 62a which is cylindrical in shape. Therefore, each of the signal output teeth 71 can be made wider in the crankshaft longitudinal direction, in comparison with the conventional pulse rotor which is disk-shaped. Thereby, the performance for detecting the ignition signals is enhanced. Namely, with the construction, failure in detecting the signal output teeth 71 by the sensor 40 is effectively prevented.
As shown in
The annular reinforced part 72 is formed on the outer peripheral wall 62a on the side of the open end of the clutch outer member 62. With the construction, a part of the outer peripheral wall 62a which is most likely to be distorted by a load exerted radially outwardly from the clutch member 64, is reinforced effectively. Namely, thereby, the distortion of the outer peripheral wall 62a is prevented.
The sensor 40 is mounted on the crankcase 1 along with the rubber packing 74 which supports the wire leads 76. According to the construction, in comparison with those members being mounted separately on the first cover 11 and the crankcase 1 for example, the wire leads 76 are easy to handle and arrange when the first cover 11 is attached to, or removed from, the crankcase 1. Therefore, with the construction, the assemblage and maintenance of the signal detector becomes easy.
As shown in the figures, the signal output teeth 710b are formed on a corner on the side of an end wall part 620c of the outer peripheral wall 620b of the clutch outer member 62, and the outer peripheral wall 620b on the side of the open end of the clutch outer member 62, with respect to the signal output tooth 710b, is formed as an annular reinforced part 720b. The sensor 40 is positioned radially outside the signal output tooth 710b, so as to be opposed to the signal output tooth 710b. The region “W2” of the signal output tooth 710b in the crankshaft longitudinal direction, is set so as not to overlap the region of the clutch member 64 in the crankshaft longitudinal direction.
As aforementioned, the bottom of the signal output tooth 710b is formed as the through-hole partially which is penetrated through the outer peripheral wall 620b. Therefore, the thickness of the part of the bottom of the signal output tooth 710b is 0 mm. According to this construction, the thickness T4 of the annular reinforced part 720b, is greater than the thickness (namely, 0 mm) of the part of the bottom of the signal output tooth 710b.
The shapes and/or constructions of the signal output teeth as a signal output part, are not limited to those according to the embodiment and modifications as explained above. It is alternatively possible to adopt any shape and/or construction of the signal output teeth formed such that the outer peripheral wall of the clutch outer member 62 has a continuous concavity and convexity which can be detected by the sensor 40. More specifically, for example, such a continuous concavity and convexity can be in a form of a rounded peak as its outer peripheral part and a trough as its inner peripheral part which are formed alternately.
The present invention preferably applies to the two-wheeled motor vehicle. However, it goes without saying that the present invention can apply to another type of vehicle.
According to the embodiment shown in
According to the aforementioned embodiment, both of the sensor 40 and the rubber packing 74 supporting the wire leads 76 are accommodated inside the crankcase 1. Alternatively, it is also possible to house both the members 40, 74 inside the first cover 11 for the starter 10.
Although the present invention has been fully described in connection with the preferred embodiment thereof with reference to the accompanying drawings, it is to be noted that various other changes and modifications are also apparent to those skilled in the art. Such changes and modifications are to be understood as included within the scope of the present invention as defined by the appended claims unless they depart therefrom.
Number | Date | Country | Kind |
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P2005/044102 | Feb 2005 | JP | national |