Patent Application
20150114364
1. Field of the Invention
The present invention relates to a supercharger mounting structure with which a supercharger is fitted to a combustion engine that is mounted on an automotive vehicle such as, for example, a motorcycle.
2. Description of Related Art
In a combustion engine mounted on the automotive vehicle such as, for example, a motorcycle, the use has been known of a supercharger for supplying an outside air into the engine after the latter has been pressurized. In this respect, see, for example, the Japanese patent document 1 listed below. This known supercharger is so configured as to be driven in operative association with rotation of an engine rotary shaft. As a merit to use such configuration, the air intake efficiency of an air intake system is enhanced, and accordingly, the output of the combustion engine is increased.
Patent Document 1: JP Laid-open Patent Publication No. 02-163539
The supercharger of the type referred to above has been known in which the use is made of a compressing unit for supplying an intake air under pressure to the combustion engine and a speed increasing unit for increasing the speed of rotation of the engine rotary shaft and then transmitting the increased rotation of the engine rotary shaft to the compressing unit. If the compressing unit and the speed increasing unit are separately mounted on an engine body, the workability of assembling and disassembling of the supercharger is lowered.
The present invention has been devised to substantially eliminate the foregoing problems and inconveniences and is intended to provide a supercharger mounting structure for the engine, which enables the supercharger to be selectively mounted on and removed from the engine main body. In order to accomplish the foregoing object, the present invention herein disclosed provides a supercharger mounting structure used to mount a supercharger on the engine, which includes a supercharger made up of a compressing unit to supply an intake air under pressure to the engine, a speed increasing unit to increase the speed of rotation of an engine rotary shaft and then to transmit the increased rotation of the engine rotary shaft to the compressing unit, and a supercharger casing having the compressing unit and the speed increasing unit both accommodated therein, with the supercharger casing being removably fitted to a crankcase of the engine.
According to the present invention, the compressing unit and the speed increasing unit are accommodated within the supercharger casing that is detachably fitted to the crankcase of the engine, to thereby form a single assembly. Accordingly, the supercharger can easily be fitted to or removed from the engine selectively.
In the supercharger mounting structure for the engine referred to above, preferably, the crankcase has an upper portion formed with an opening, and a power of the engine is transmitted to the speed increasing unit by means of a power transmitting member that extends, having been passed completely, through the opening. According to this structural feature, since the power transmitting member extends, having been passed completely, through the opening, in the case that the supercharger is disposed above the crankcase, a power of the engine can be smoothly transmitted to the supercharger by means of a power transmitting member which is disposed at a position axially adjacent to the supercharger.
In a preferred embodiment of the present invention, the supercharger casing may include a casing main body to enclose the upper portion of the crankcase and a compressing unit housing to accommodate therein the compressing unit. In this case, the compressing unit housing preferably has a portion which protrudes downwardly below an undersurface of the casing main body in a condition connected with the casing main body. According to this structural feature, if the compressing housing and the casing main body are separately formed, it is possible to avoid an undesirable increase of the dimension of the casing main body in an up and down direction or vertical direction.
Particularly where the supercharger casing includes the casing main body and the compressing unit housing, the crankcase may have an upper surface including an abutment surface area, that is held in abutment with the casing main body, and a confronting surface area confronting to the compressing unit housing in a direction conforming to an axial direction of the supercharger. The confronting surface area is preferably formed below the abutment surface area. According to this structural feature, since the confronting surface area is formed below the abutment surface area, the amount of projection upwardly from the crankcase of the supercharger can be suppressed while the interference between the upper surface of the crankcase and the compressing unit housing is avoided.
Particularly where the abutment surface area and the confronting surface area are formed in the upper surface of the crankcase, the upper surface of the crankcase referred to above may also include an extension surface area extending from the confronting surface area in an axial direction of the compressing unit towards one side opposite to the abutment surface area. In this case, the extension surface area is preferably formed together with the confronting surface area below the abutment surface area. According to this structural feature, the extension surface area may be used to accommodate, for example, an air intake duct disposed thereon, which duct is fluid connected with the compressing unit.
In another preferred embodiment of the present invention, so that a rotary shaft of the compressing unit may be disposed above the upper surface of the crankcase, the supercharger casing preferably accommodates therein a support unit configured to support the rotary shaft. According to this feature, even if a rotary body of the compressing unit, for example, an impeller is disposed above the crankcase, the interference between the rotary body and the crankcase in the vertical direction can be avoided when the support unit for the rotary shaft is accommodated within the supercharger casing.
In a further preferred embodiment of the present invention, a drive shaft drivingly connected with the engine rotary shaft to drive the supercharger may be supported by the crankcase. In this case, a switching mechanism may be mounted on the drive shaft to switch a power path of the supercharger, and a change drum operable to actuate the switching mechanism through a shift fork may be accommodated within the supercharger casing. According to this structural feature, since the change drum is also accommodated within the supercharger casing, mounting of the change drum can be facilitated.
Where the shift fork is used, the change drum or the shift fork preferably extends, having been passed, through the opening formed in the upper portion of the crankcase. According to this structural feature, since the change drum or the shift fork extend having been passed through that opening, as compared with the disposition of them on a side surface of the crankcase, the change drum and the shift fork can be easily disposed on an inner side of the combustion engine.
Again, where the shift fork and the change drum are used, a shifter drive unit to drive the change drum may be removably fitted to the supercharger casing. According to this structural feature, in a condition prior to the fitting of the shifter drive unit, the shift fork can be engaged in the supercharger casing and, accordingly, the assemblability can be increased.
Any combination of at least two constructions, disclosed in the appended claims and/or the specification and/or the accompanying drawings should be construed as included within the scope of the present invention. In particular, any combination of two or more of the appended claims should be equally construed as included within the scope of the present invention.
In any event, the present invention will become more clearly understood from the following description of preferred embodiments thereof, when taken in conjunction with the accompanying drawings. However, the embodiments and the drawings are given only for the purpose of illustration and explanation, and are not to be taken as limiting the scope of the present invention in any way whatsoever, which scope is to be determined by the appended claims. In the accompanying drawings, like reference numerals are used to denote like parts throughout the several views, and:
Hereinafter, the present invention will be described in detail in connection with preferred embodiments thereof Before the description of the present invention proceeds, it is to be noted that the terms “left” and “right” used herein are to be understood as nomenclatures used to denote opposite directions or positions as viewed from a vehicle driver then maneuvering the automotive vehicle, respectively.
On the other hand, a swingarm bracket 12 is provided in a rear end portion of the main frame 1, which is a lower intermediate portion of the motorcycle frame structure FR. A swingarm 20 is supported by the swingarm bracket 12 for movement up and down, and a rear wheel 22 is supported by a rear end portion of the swingarm 20 for pivotal movement about a pivot pin 23. A motorcycle combustion engine E is mounted on the lower intermediate portion of the motorcycle frame structure FR and is positioned on a front side of the swingarm bracket 12. Rotation of the combustion engine E is transmitted to a transmitting mechanism 24 such as, for example, a substantially endless chain, and the rear wheel 22 is driven through this transmission mechanism 24. The combustion engine E is in the form of a parallel multicylinder engine in the form of, for example, a four-cylinder, four-cycle combustion engine. It is, however, to be noted that the type of the combustion engine E is not necessarily limited to that referred to above. A rear portion cushioning mechanism 25, configured to absorb a load between the rear wheel 22 and the rear frame 2, is connected between the rear frame 2 and the swingarm 20.
A fuel tank 28 is disposed on an upper portion of the main frame 1, and a driver's seat 30 and a fellow passenger's seat 32 are supported by the rear frame 2. Also, a front fairing or cowling 34, made of a resinous material, is mounted on a front portion of the motorcycle body so as to cover an area ranging from forwardly of the head pipe 4 to opposite lateral portions of the front portion of the motorcycle body. The front cowling 34 has a headlamp unit 36 mounted thereon, and an air intake opening 38 positioned beneath the headlamp unit 36 for introducing the ambient air therethrough into the combustion engine E is defined in the front cowling 34.
With the air intake opening 38 open in a direction forwardly of the motorcycle body, the amount of air drawn towards the combustion engine E can be increased by the utilization of the wind pressure of the incoming wind A. The air intake opening 38 is disposed in a front surface of the front cowling 34 and is positioned at a nose portion of the front cowling 34 at which the highest wind pressure of the incoming wind is available. In the illustrated embodiment, the air intake opening 38 is shown as positioned below the headlamp unit 38, but it may be positioned above the headlamp unit 36, or at a position intermediate between two headlamps spaced apart from each other in a direction laterally of the motorcycle body in the case of any known twin headlamp structure.
The combustion engine E includes a crankcase 40 for supporting an engine rotary shaft 39 that extends in a direction conforming to the motorcycle widthwise direction, a cylinder block 42 protruding upwardly from the crankcase 40, a cylinder head 44 mounted on the cylinder block 42, a head covering 46 fitted to an upper portion of the cylinder head 44 so as to cover a cam mechanism (not shown) for intake and exhaust valves, and an oil pan 50 provided beneath the crankcase 40. The crankcase 40 has a rear portion concurrently serving as a transmission casing. The cylinder block 42 is somewhat tilted forwardly. The cylinder head 44 has a rear portion provided with an air intake port 47. Four exhaust pipes 54 fluid connected with an exhaust port at a front surface of the cylinder head 44 are merged together at a location beneath the combustion engine E and then fluid connected with an exhaust muffler 56, which is disposed on a right side of the rear wheel 22.
A supercharger 62, which forms an intake unit through which an outside air is drawn and is then supplied towards the combustion engine E, is disposed rearwardly of the cylinder block 42 and above the crankcase 40. This supercharger 62 includes a supercharger rotating shaft 64 extending in a direction parallel to the motorcycle widthwise direction, an air intake port 66 open leftwards at allocation above the crankcase 40, and a discharge port 68 disposed rearwardly of the supercharger rotating shaft 64 in a portion of the combustion engine E intermediate of the motorcycle widthwise direction. The intake port 66 of the supercharger 62 is disposed on an inner side of a left side surface of the cylinder block 42 with respect to the motorcycle widthwise direction, and an air intake duct 70 for introducing the incoming wind A, then flowing forwardly of the cylinder block 42, into the supercharger 62 is fluid connected with the intake port 66.
This air intake duct 70 is disposed on a left side, which is one side of the combustion engine E, and includes a ram duct unit 51 on an upstream side and an air intake duct section 53 on a downstream side. The ram duct unit 51 is supported by the main frame 1 with its front end opening 51a facing the air intake opening 38 defined in the previously described cowling 34 and serves to increase the pressure of the air introduced from the front end opening 51a under the ram effect. The ram duct unit 51 has a rear end portion 51 b to which a front end portion 53a of the air intake duct section 53.
As shown in
The discharge port 68 of the supercharger 62 referred to previously is oriented upwards and, at a location between this discharge port 68 and the four air intake ports 47 (shown in
A throttle body 76 is disposed between the intake air chamber 74 and the cylinder head 44. In this throttle body 76, fuel is injected into the intake air to thereby form an air/fuel mixture, which is in turn supplied into respective combustion chambers 72 (shown in
As shown in
The compressing unit 61 includes an impeller which is a rotating element or a rotor, and the outside air guided into the air intake port 66 during the rotation of the impeller is discharged from the discharge port 68 after the pressure thereof has been increased. The impeller is rotatable with the rotation of the engine rotary shaft 39 (
The speed increasing unit 63 referred to above is operable to transmit the rotation of the engine rotary shaft 39 (shown in
The casing main body 69 referred to above includes a speed increasing unit storage 75 for accommodating therein the speed increasing unit 63 and a drum storage 77 for accommodating therein a change drum 108 (best shown in
The upper surface 40a of the crankcase 40 is formed with an opening 150, and this opening 150 is closed by the casing main body 69 then supported by the upper surface 40a of the crankcase 40. In other words, the casing main body 69 shown in
As shown in
The speed increasing unit storage 75 of the casing main body 69 includes a cylindrical casing flange 69a formed at a junction with the compressing unit housing 71, and a second confronting surface area 155 confronting the casing flange 69a in the upper surface 40a of the crankcase 40 is downwardly depressed also from the abutment surface area 152. Within the casing flange 69a, a planetary gear device (shown in
As shown in
As shown in
A starter motor 90 is connected with the starter gear 86 through a torque limiter 88. Accordingly, when the starter motor 90 is rotated in a condition in which the combustion engine E is halted, the one way clutch 85 is coupled so that a start torque is transmitted to the crankshaft 39. Also, when the rotational speed of the crankshaft 39 becomes lower than that of the starter motor 90 subsequent to the start of the combustion engine E, the one way clutch 85 is decoupled to inhibit the power transmission from the crankshaft 39 to the starter motor 90. Since the starter motor 90 is, as shown in
As shown in
Also, a sprocket 100 is provided on a right side end portion of the supercharger drive shaft 82 and, through a power transmitting body 102, which is in the form of a stripe shaped endless transmitting member and is operable to transmit the power of the combustion engine to the supercharger 62, a rotational force of the supercharger drive shaft 82, that is, a rotational force of the crankshaft 39 is transmitted to the input shaft 65 coupled with the supercharger rotating shaft 64. In the embodiment now under discussion, the power transmitting body is shown and described as employed in the form of a chain 102. The method of driving the supercharger 62 is not necessarily limited to that described above.
The chain 102 referred to above is disposed on the right side, which is opposite to the air intake port 66 of the supercharger 62, shown in
Between the third speed change gear 96 and the fourth speed change gear 98 both on the supercharger drive shaft 82, a shifter 104 is disposed. The shifter 104 includes a shift ring 105, a shift fork 106 for operating the shift ring 105, and a change drum 108 for moving the shift fork 106 in parallel to the supercharger drive shaft 82. With the shift ring 105 splined to the supercharger drive shaft 82, the shift ring 105 is rendered to be non-rotatable relative to, but axially movable relative to the supercharger drive shaft 82.
The change drum 108 moves the shift fork 106 in the axial direction, having been rotationally driven by a shifter drive unit 110, to enable an engagement hole 105a of the shift ring 105 to be engaged with one of dogs 96a and 98b provided respectively in the third and fourth speed change gears 96 and 98. Thereby, the shift ring 105 is selectively and relatively non-rotatably engaged with one of the third and fourth speed change gears 96 and 98.
Through the selected speed change gear 96 and 98, the power is transmitted from the countershaft 78 to the supercharger drive shaft 82. In other words, when a dogged connection establishes between the shift ring 105 and the third speed change gear 96, the rotation of the countershaft 78, that is, the rotation of the crankshaft 39 is transmitted to the supercharger drive shaft 82 at a large speed increasing ratio. On the other hand, when a dogged connection establishes between the shift fork 106 and the fourth speed change gear 98, the rotation of the countershaft 78 is transmitted to the supercharger shaft 82 at a small speed reducing ratio. Also, so long as no dogged connection establish, no transmission of the power to the supercharger shaft 82 takes place. The shifter drive unit 110 used is of a type employing, for example, a servomotor, but it is not necessarily limited thereto. Accordingly, the rotational force of the crankshaft 39 is transmitted from the countershaft 78 to the supercharger drive shaft 82 of the supercharger 62 through the selected speed gear 96 or 98.
The shifter dive unit 110 causes the shift fork 106 in the axial direction of the change drum 108 in dependence on, for example, the number of rotations of the combustion engine E to allow one of the third and fourth speed change gears 96 and 98, which is appropriate to the number of rotations, to be selected. Specifically, at a low rotational region of the combustion engine E, setting is made that the shift ring 105 is in a dogged connection with the third speed change gear 96 to increase the speed increasing ratio of the supercharger 62 to thereby increase the supercharger pressure, that is, the amount of air supercharged so that the engine torque at a low speed can be earned. On the other hand, at a high rotational region of the combustion engine E, setting is made that the shift ring 105 is in a dogged connection with the fourth speed gear 98 to lower the speed increasing ratio of the supercharger 62 to thereby prevent the amount of air supercharged from increasing excessively so that a proper engine torque and a stabilized rotation can be obtained. Also, where no supercharging is required, the shift fork 106 is moved to a position at which no dogged connection establishes.
In the embodiment now under discussion, the change drum 108 is shown as disposed above the top opening 150, but the change drum 108 may be disposed at a position at which it traverses the top opening 150. Also, the shifter drive unit 110 is removably fitted to an outer surface of the supercharger casing 67. In this way, the assembly of the supercharger 62 including the compressing unit 61, the speed increasing unit 63, a compressor casing 67, the shift fork 106, the change drum 108, the shifter drive unit 110, etc. is formed.
The compressing unit housing 71 includes a casing portion 116 for rotatably supporting the supercharger rotating shaft 64 through bearings 121. Using a casing fastening member 122 such has, for example, bolts, a housing portion 124 for enclosing the impeller 114 is fitted to a first flange 116 on one end side of the casing portion 116. A second flange 116b at the other end side of the casing portion 116 is fixed to the casing flange 69a of the main body casing 69, supported by the crankcase 40, by means of the previously described housing fastening member 118. In other words, the bearings 121 form a support unit for the supercharger rotating shat 64.
In this way, the supercharger rotating shaft 64 and the bearings 121, which form its support unit, are enclosed by the casing portion 116, and the impeller 114 is enclosed by the housing portion 124. The housing portion 124 is formed with the intake port 66, which opens on the one end side, and the discharge port 68 which opens upwardly.
The input shaft 65 is in the form of a hollow shaft and is rotatably supported by the casing main body 69 through bearings 123. Spline serrations are formed on an outer peripheral surface of the other end portion 65b of the input shaft 65 and, through a one way clutch 128 mounted on the outer peripheral surface by means of the spline engagement, a sprocket 130 is connected with the input shaft 65. The chain 102 referred to previously is trained around teeth 132 of the sprocket 130, and the rotation of the supercharger rotating shaft 82 (shown in
Female threaded portion is formed on an inner peripheral surface of the other end portion 65b of the input shaft 65, and the one way clutch 128 is mounted on the other end portion 65b through a washer 136 by means of a bolt 134 threadingly engaged with this female threaded portion. The one way clutch 128, the sprocket 130 and the bolt 134 are all accommodated in a sprocket covering 129 that is jointed to the other end of the speed increasing unit storage 75 in the supercharger casing 67 shown in
As hereinbefore described, the planetary gear device 112 shown in
The carrier shaft 144 has a fixture member 146, and this fixture member 146 is fixed to the casing portion 116 by means of a bolt 145. In other words, the carrier shaft 144 is fixed to the casing portion 116. An input gear 147 provided on the one end portion of the input shaft 65 is meshed with the internal gear 142. In this way, the internal gear 142 is meshed with the input shaft 65 so that it will rotate in the same direction as that of the input shaft 65 and, with the carrier shaft 144 fixed, the planetary gear 140 rotates in the same direction as that of the internal gear 142. The sun gear (external gear 138) is formed in the supercharger rotating shaft 64, which serves as the output shaft, and rotates in a direction counter to the direction of rotation of the planetary gears 140. In other words, the planetary gear device 112 increases the speed of rotation of the input shaft 65 and transmit it to the supercharger rotating shaft 64 in a direction counter to the input shaft 65.
When the combustion engine E rotates, the crankshaft 39 shown in
When the motorcycle travels, the incoming wind passes from the air intake opening 38 and through the random duct unit 51 and, is, after having been purified by the air cleaner 55, introduced into the supercharger 62 by way of the air intake duct section 53. The incoming air A so introduced into the supercharger 62 is pressurized by the supercharger 62 and is then introduced into the combustion engine E through the intake air chamber 74 and the throttle body 76. By the cumulative effect of the ram pressure and the pressurization by the supercharger 62, the high pressure intake air can be supplied into the combustion engine E.
In the construction described hereinabove, within the supercharger casing 67 removable relative to the crankcase 40 of the combustion engine E as shown in
Also, since the chain 102 extends having been passed completely through the top opening 150 of the crankcase 40, even when the supercharger 62 is disposed above the crankcase 40, the power of the combustion engine E can be smoothly transmitted to the supercharger 62 by means of the chain 102 disposed at a position proximate to the supercharger 62 in the axial direction.
As shown in
Also, since the first confronting surface area 154 is formed beneath the abutment surface area 152, the amount of projection of the supercharger 62 in a direction upwardly from the crankcase 40 can be suppressed while the interference between the upper surface 40a of the crankcase 40 and the compressing unit housing 71 is avoided.
Furthermore, the upper surface 40a of the crankcase 40 is formed with the extension surface area 156 extending from the first confronting surface area 154 in a direction counter to the abutment surface area 152 (
As shown in
As shown in
Also, since the shifter drive unit 110 is removably fitted to the supercharger casing 67, the shift fork 106 can be inserted into the supercharger casing 67 in a condition prior to the fitting of the shifter drive unit 110 and, therefore, the assemblability increases. Yet, it can readily be adopted to the type of the engine with no supercharger 62.
The front frame 1 A has a front end formed integrally with the head pipe 4, the steering shaft (not shown) is rotatably supported by this head pipe 4, and the steering handlebar 6 is fixed to this steering shaft. In other words, the head pipe 4 functions as a handlebar post, and the front frame 1A, which is a part of the motorcycle frame structure FR, extends from the head pipe 4 in a direction rearwardly of the motorcycle body. It is to be noted that in
Forked arms 200 extending in a direction forwardly from the combustion engine E are supported by a front portion of the crankcase 40 of the combustion engine E for movement up and down. A hub steering mechanism (not shown) for steerably supporting the front wheel 10 is fitted to tip end portions of left and right pairs of arm pieces 200a and 200b of those arms 200. Also, there are provided a steering mechanism (not shown) for steering the front wheel 10 by means of the hub steering mechanism by transmitting the manipulation of the steering handle 6 and a front suspension (not shown) for cushioning in response to a load imposed on the front wheel 10. Other structural features than those described above are similar to those afforded by the previously described embodiment and, therefore, effects similar to those afforded by the previously described embodiment can be obtained.
Although the present invention has been fully described in connection with the preferred embodiments thereof with reference to the accompanying drawings which are used only for the purpose of illustration, those skilled in the art will readily conceive numerous changes and modifications within the framework of obviousness upon the reading of the specification herein presented of the present invention. By way of example, besides that employed in the embodiments shown and described, the present invention is applicable to a cradle frame, a diamond frame or a backbone frame. Also, the supercharger mounting structure can be equally applied to any other saddle-riding automotive vehicle than the motorcycle and is applicable to, for example, a three wheeled automotive vehicle or a four wheeled automotive vehicle. In addition, the present invention can be equally applied to anything other than the engine mounted on the automotive vehicle.
Also, in describing the preferred embodiment, the switching mechanism 99 has been shown and described as having the speed change ratio that is switchable, it may be so constructed as to switch between a neutral condition and a gear meshed condition. Yet, any other compressing structure than the impeller 114, which has been shown and described as forming the compressing unit 61, can be employed.
Accordingly, such changes and modifications are, unless they depart from the scope of the present invention as delivered from the claims annexed hereto, to be construed as included therein.
| Number | Date | Country | Kind |
|---|---|---|---|
| 2012-155463 | Jul 2012 | JP | national |
This application is a continuation application, under 35 U.S.C §111(a) of international application No. PCT/JP2013/068915, filed Jul. 10, 2013, which claims priority to Japanese patent application No. 2012-155463, filed Jul. 11, 2012, the entire disclosure of which is herein incorporated by reference as a part of this application.
| Number | Date | Country | |
|---|---|---|---|
| Parent | PCT/JP2013/068915 | Jul 2013 | US |
| Child | 14590888 | US |
