JPH0320139A - Balancer unit for interval combustion engine - Google Patents

Abstract

PURPOSE:To promote the lightweightiness and miniaturization of an engine by installing a balancer weight solidly in a tubular shaft supported around a main shaft of a gear shifter free of rotation, while also installing a clutch unit as one body free of rotation. CONSTITUTION:A balancer weight 9 is solidly installed in one end of a tubular shaft 40 supported around a main shaft 5 of a gear shifter 3 free of rotation, while a clutch unit 7 is installed as one body in the other end free of rotation. Then, this clutch unit 7 is connected to a crankshaft 1 via a primary driven gear 38 and a primary driving gear 37 installed free of rotation as one body. In addition, a secondary balancer weight 10 different from the primary balancer weight 9 is solidly installed in a tubular shaft 48 supported around a countershaft 6 free of rotation, and it is rotated and driven by the tubular shaft 40 via a driving gear 46 and a driven gear 49. Thus the lightweightiness and miniaturization of an engine can be well promoted.

Description

[Detailed description of the invention] (Industrial application field) The present invention relates to a balancer device for an internal combustion engine.

(Prior Art) A balancer device for an internal combustion engine reduces vibrations during operation of the internal combustion engine by rotating a primary balancer weight in the opposite direction at the same speed as the crankshaft. Furthermore, in some cases, the secondary balancer weight is rotated at twice the speed of the crankshaft to reduce secondary vibrations.

As a balancer device of this type, especially a balancer device equipped with a primary balancer weight, for example, Japanese Patent Laid-Open No. 58-39
As disclosed in Japanese Patent No. 863, a primary balancer weight is rotatably held on the main shaft of a transmission that is interlocked with the crankshaft via a clutch device, and a driven sprocket is integrally formed with the balancer weight. A known balancer weight is connected to a drive sprocket formed on a crankshaft via a chain, thereby causing the balancer weight to rotate in synchronization with the crankshaft.

However, in this balancer device, a dedicated driven sprocket for rotating the eight lancer weights is provided on the main shaft and sub-shaft, and a dedicated driving sprocket is provided on the crankshaft, making the internal combustion engine smaller and lighter. This was a hindrance to efforts to achieve this goal.

In addition, the provision of dedicated sprockets and chains increases the number of parts in the internal combustion engine, increasing the number of assembly steps, which hinders the reduction of manufacturing costs.

(Problems to be Solved) The present invention eliminates such disadvantages and makes it possible to easily reduce the size and weight of an internal combustion engine by using a balancer device with a reduced number of parts by using the main shaft of a transmission, etc. The purpose is to provide the following. A further object of the present invention is to provide a balancer device that can reduce rotational torque acting on a clutch device and a main shaft of an internal combustion engine.

Further, it is an object of the present invention to provide a balancer device that can easily reduce the weight of the component parts of the balancer device, can make effective use of the space, and can further improve its assembly workability. With the goal.

Furthermore, it is an object of the present invention to provide a balancer device that can effectively utilize the balancer device in terms of its operation.

(Means for Solving the Problems) In order to achieve the above object, the balancer device for an internal combustion engine of the present invention includes a main shaft that is interlocked with the crankshaft via a clutch device, and a subshaft that is interlocked with the main shaft via a transmission gear. In an internal combustion engine, the balancer weight rotates concentrically around the main shaft, and the balancer weight rotates concentrically with the main shaft. The clutch device is provided integrally with a movably supported hollow shaft, and the clutch device is rotatably provided integrally with the hollow shaft, and is mounted on the crankshaft so as to be rotatable at the same speed and in the opposite direction. It is characterized by being connected to.

Furthermore, the clutch device is connected to the crankshaft via a primary driven gear rotatably provided therewith and a primary drive gear provided on the crankshaft.

Further, the balancer weight is provided at one end of the hollow shaft, and the clutch device is provided at the other end of the hollow shaft.

Further, the balancer weight is integrally provided at one end of the hollow shaft, the clutch device is fitted and connected to the outer peripheral surface of the other end of the hollow shaft, and the balancer weight of the hollow shaft is provided. It is characterized in that one end is housed in a case that houses the transmission, and the other end that connects the clutch device projects outside the case.

Further, it is characterized in that it includes another balancer weight different from the primary balancer weight, and a drive gear for rotating the other balancer weight is provided integrally with the hollow shaft.

Furthermore, the other balancer weight is a secondary balancer weight.

Further, a driven gear provided integrally with the secondary balancer weight is meshed with the drive gear, and the primary balancer weight is rotatably provided between the secondary balancer weight and the driven gear. It is characterized by

(Function) According to this means, the primary balancer weight is rotatably provided integrally with the clutch device via the hollow shaft that is integral with the primary balancer weight, and the clutch device is mounted on the crankshaft with the same rotation. Since the primary balancer weight is connected to rotate at the same speed and in the opposite direction, by interlocking the main shaft with the crankshaft via the clutch device, the primary balancer weight can rotate at the same speed as the crankshaft and in the opposite direction. This eliminates the need for a dedicated drive means for rotating the balancer weight.

Further, at this time, since the main shaft of the transmission rotates together with the clutch device and the primary balancer weight at the same speed as the crankshaft, the clutch device and the main shaft are rotated with a relatively small rotational torque.

Further, when the clutch device is connected to the crankshaft via the primary driven gear and the primary drive gear, a rotational force is applied from the crankshaft to the hollow shaft and the primary balancer weight via the heavy clutch device. is transmitted.

Further, when the balancer weight and the clutch device are provided at both ends of the hollow shaft, it becomes easier to ensure the rigidity of the hollow shaft by balancing the weight of the balancer weight and the clutch device, and the balancer weight and the clutch device are provided at both ends of the hollow shaft. It becomes possible to utilize the space between the weight and the clutch device.

Further, the balancer weight is integrally provided at one end of the hollow shaft housed in the case, and the clutch device is fitted onto an outer peripheral surface of the other end of the hollow shaft protruding outside the case. When connected, the work of assembling the balancer device involves inserting the hollow shaft integrated with the balancer weight around the main shaft of the transmission housed in the case, sealing the case, and then removing the hollow shaft. This is done by fitting and connecting the clutch device to the end protruding from inside the case.

Further, when a drive gear for rotating the other balancer weight is integrally provided with the hollow shaft, the hollow shaft rotated together with the primary balancer weight rotates the other balancer weight. be used effectively.

Furthermore, when the other balancer weight is a secondary balancer weight, the secondary balancer weight is interlocked with the crankshaft by simply connecting the hollow shaft and the secondary balancer weight via a pair of gears. It is now possible to rotate it. Further, when the primary balancer weight is rotatably provided between the secondary balancer weight and a driven gear integrally provided therewith, Since it is located in the space between the secondary balancer weight and the driven gear during movement, the space is effectively utilized, and the combined length of both balancer weights and both gears in the direction of the main shaft is shortened. (Example) A single-cylinder four-stroke engine for a motorcycle equipped with an example of the balancer device for an internal combustion engine of the present invention will be described with reference to FIGS. 1 to 4. 1 to 3 are explanatory cross-sectional views of main parts of the engine in a front view, a plan view, and a side view, respectively, and 4W is a cross-sectional view taken along the line ■■ in FIG. 3.

In Figs. 1 to 3, l denotes a crankshaft rotatably supported by the crankcase 2, and 3 denotes a crankshaft rotatably supported by the crankcase 2 and connected to each other via a transmission gear train 4. A transmission device includes a main shaft 5 and a subshaft 6, 7 is a clutch device mounted on the main shaft 5 of the transmission 3 outside the crankcase 2, and 8 is a clutch device mounted around the main shaft 5 and subshaft 6 inside the crankcase 2, respectively. The primary balancer weight 9 and the secondary balancer weight lO are rotatably provided, and the primary balancer weights l2 and 2 are rotatably provided around the balancer shaft l1 rotatably supported by the crankcase 2. A balancer device 14 includes a next balancer weight 13, a cylinder block l5 mounted on the crankcase 2;
A piston 16 is provided on the crankcase 2 and drives the transmission 3, and l7 is mounted on the cylinder block l5 to form a combustion chamber l8 between the piston l4 and the piston l7. A cylinder head equipped with an intake/exhaust passage (not shown) that communicates with the combustion chamber 18, 19 is an intake/exhaust device installed in a head force bar 20 mounted on the cylinder head 17, and performs intake/exhaust to the combustion chamber 18; This is a generator attached to the end of the crankshaft l outside the crankcase 2. Further, in FIG. 4, 22 is a kick starter provided in the crankcase 2 to start the engine.

As shown in the first figure, the crankshaft l has a pair of crank webs 23 and 24 housed in the crankcase 2, and a bearing 25. It is rotatably supported via 26. This crankshaft l is formed by a crank half body 27 having a crank web 23 and a crank half body 28 having a crank web 24, which are formed by a crank bin 29 formed integrally with the crank web 23 and press-fitted into the crank web 24. are combined together. The crank pin 29 is connected to the piston l4 via a connecting rod 30, and as the piston l4 moves up and down, the crankshaft 1 is rotated about its axis. Further, the end face of the crankcase Z side of the portion of the crank web 23 where the crank pin 29 is provided is cut into a slope shape and made thin, thereby forming a space between it and the crankcase 2.

The main shaft 5 of the transmission 3 has a bearing 31. as shown in the first figure. 32, the clutch device 7 is rotatably supported by the crankcase 2 and is provided parallel to the crankshaft 1, and the clutch device 7 is provided at an end protruding from inside the crankcase 2.
are connected. As shown in the second diagram, the clutch device 7 includes a clutch outer 33 that is placed close to the crankcase 2 and inserted around the end of the main shaft 5, and a clutch outer 33 that is housed inside and rotates integrally with the main shaft 5. The clutch inner 34 is freely attached.
4 and the lifter plate 35, the lifter plate 35 is rotatable concentrically with the main shaft 5 via a plurality of clutch plates 36 which are overlaid and crimped to each other. On the end faces of the two crankcases of the clutch outer 33, there is a one-to-one connection with a primary drive gear 37, which is rotatably attached to the end of the crankshaft l protruding from the inside of the crankcase 2. A primary driven gear 38 meshed with the gear ratio is fixed concentrically with the main shaft 5, and the primary driven gear 38 is rotatably fitted onto the main shaft 5 via a twenty-one dollar bearing 39, and is connected to the main shaft 5 and the main shaft 5. The hollow shaft 40 interposed between the hollow shaft 40 and the bearing 32 is rotatably fitted to the outer peripheral surface of the end protruding from the inside of the crankcase 2 by spline connection.

Therefore, when the crankshaft l is rotated as described above,
The tarlatch outer 33 and the hollow shaft 40 rotate around the axis of the main shaft 5 at the same speed and in the opposite direction to the crankshaft l through the primary drive gear 37 and the primary driven gear 38, and furthermore, the tarlatch outer 33 and the hollow shaft 40 rotate around the axis of the main shaft 5 in the opposite direction to the crankshaft l, and furthermore, the The clutch inner 34 and main shaft 5 are connected to the taratch outer 3 via the clutch plate 36 of
3 and the hollow shaft 40 around its axis.

As shown in the first diagram, the clutch device 7 includes a push rod 41 slidably inserted into the main shaft 5 toward the lifter plate 35, and the push rod 4l is moved toward the lifter plate 35 by a clutch drive device (not shown). is slid in the direction away from the clutch inner 34 to release the mutually pressed state of the clutch plates 36. At the time of release, the clutch device 7 is in a disconnected state, and the clutch inner 34 and the main shaft 5 are Does not rotate.

A subshaft 6 of the transmission 3 (as shown in the first diagram, is rotatably supported in the crankcase 2 via bearings 42, 43 and is provided parallel to the crankshaft 1, and is provided in parallel to the crankshaft 1. It is connected to the main shaft 5 via a gear train 4, and rotates in conjunction with the raw shaft 5 at several speeds depending on the meshing combination of the transmission gear train 4, similar to known transmission devices. A driving sprocket 44 is rotatably attached to the end of the countershaft 6 that protrudes from inside the crankcase 2, and the driving sprocket 44 is connected to a wheel (not shown) via a chain 45. The rotation of the subshaft 6 is transmitted to the wheels.

Therefore, the driving force of the engine accompanying the vertical movement of the piston l4 is transmitted to the crankshaft 1, the clutch device 7, and the transmission device 3.
The signal is output from the subshaft 6 of the transmission 3 to the wheels via the auxiliary shaft 6 of the transmission 3 in sequence.

One primary balancer weight 9 of the balancer device 8
(hereinafter referred to as primary balun-}!-9) is provided integrally with the end of the hollow shaft 40 inside the crankcase 2 as shown in the second diagram, and therefore, the hollow shaft 40 and the clutch outer 33 It is designed to be able to freely rotate around the axis of the main shaft 5 at the same speed as the crankshaft l and in the opposite direction. A drive gear 46 is located between the primary balancer 9 and the crankcase 2 for rotating the secondary balancer way port 0 (hereinafter referred to as secondary balancer 10) around the subshaft 6. It is provided integrally with the hollow shaft 40.

The primary balancer 9 and the drive gear 46 are provided on the crank web 23 and the crankcase 2 as close to each other as possible to prevent the hollow shaft 40 from becoming unnecessarily long. When the crankshaft l rotates 180 degrees from the state shown in the second figure, the drive gear 46 is inserted into the space formed between the crank web 23 and the crankcase 2, as shown by the imaginary line in the figure. The crank web 23 and the drive gear 46 are arranged so that they do not interfere with each other. The secondary balancer 10 has a hollow shaft 48 that is rotatably fitted onto the subshaft 6 via a twenty-one dollar bearing 47 at a position facing the hollow shaft 40 within the crankcase 2, as shown in the second figure. A driven gear 49 integrally provided at one end of the hollow shaft 48 and integrally provided at the other end of the hollow shaft 48 meshes with the drive gear 46 at a gear ratio of 2:1.

Therefore, when the crankshaft 1 rotates as described above, the primary balancer 9 rotates around the earth shaft 5 integrally with the hollow shaft 40 at the same speed as the crankshaft 1 and in the opposite direction, as shown in the third diagram. Meanwhile, the secondary balancer 10 is rotated about the subshaft 6 at twice the speed and in the same direction as the crankshaft l via the drive gear 46 and the driven gear 49. The secondary balancer 10 and the driven gear 49 are arranged so that, during this rotation, the primary balancer 9 is located between the secondary balancer IO and the driven gear 49, as shown in the imaginary line in FIG. is provided on the hollow shaft 48, thereby preventing the hollow shaft 48 from becoming unnecessarily long.

The balancer shaft 11 of the balancer device 8 has a bearing 50 attached to the crankcase 2 at a position facing the main shaft 5 across the crankshaft 1, as shown in the second figure. 51, and is provided in parallel with the crankshaft l, and the primary balancer eye 2 (hereinafter referred to as primary balancer l2) is integrally provided at the end inside the crankcase 2. ．． The primary drive gear 37 is attached to the end of the balancer shaft 11 that protrudes from inside the crankcase 2.
A driven gear 52 meshed with the balancer shaft 11 at a gear ratio of 1:1 is rotatably mounted integrally with the balancer shaft 11.

In addition, in the middle part of the balancer shaft l1 in the crankcase 2, a hollow shaft 53 with the secondary balancer way}13 (hereinafter referred to as the secondary balancer 13) integrally provided at one end has a twenty-one dollar bearing 54. A driven gear 55 is rotatably inserted through the hollow shaft 53 and is integrally provided at the other end of the hollow shaft 53.
is meshed with a drive gear 56 formed on the outer peripheral surface of the crank web 24 at a gear ratio of 2:1.

Therefore, when the crankshaft 1 rotates, the primary balancer 12 moves integrally with the balancer shaft 11 through the primary drive gear 37 and the driven gear 52 at the same speed as the crankshaft 1 and in the opposite direction. On the other hand, the secondary balancer l3 is rotated around the balancer shaft 11 integrally with the hollow shaft 53 through the driving gear 56 and the driven gear 55 at twice the speed and in the opposite direction to the crankshaft l. be moved.

In this way, in this engine, the pair of primary balancers 9
．． 12 is interlocked with the crankshaft l and rotated at a constant speed and in the opposite direction, thereby reducing the primary vibration of the engine, and furthermore, a pair of secondary balancers 10. 13 is rotated at twice the speed in conjunction with the crankshaft 1, and is also rotated in the same direction and in the opposite direction as the crankshaft 1, thereby reducing secondary vibrations of the engine. In addition, both primary balancers 9.1 of the balancer device 8
2, as shown in the second diagram, a line connecting their respective rotation centers is the crank web 23, 24 of the crankshaft 1.
The primary balancers 9 and 12 are provided at a position passing approximately the center between the two, that is, at a position where the distance from the center is approximately the same. 1 to rotate smoothly.

As shown in the first diagram, the variable speed drive device l6 includes a spindle 57 rotatably supported by a side wall on one side of the crankcase 2, and a shift drum 58 rotatably supported by the crankcase 2. The crankcase 2 is provided with a plurality of shift forks 60 slidably fitted to a shift fork shaft 59 supported in parallel with the main shaft 5 and the counter shaft 6, and each shift fork 60 is shown in FIGS. As shown, the first gear is engaged with the transmission gear train 4 of the transmission device 3, and
As shown in the figure, it is engaged with a guide groove 58a formed on the outer peripheral surface of the shift drum 58. As shown in FIGS. 1 and 3, the shift drum 58 is engaged with the spindle 57 via a link arm 6l that is rotatably attached to the end of the spindle 57 in the crankcase 2. , is rotated by the rocking of the link arm 6l as the spindle 57 rotates. The shift drum 58 is
As shown in the first figure, the end protruding from inside the crankcase 2 is connected to a stopper 62 provided on the outside of the crankcase 2, so that the rotation thereof is performed in stages. In this variable speed drive device 16, as shown in FIG. 1, the link arm 6l is operated by operating a speed change pedal (not shown) connected to the end of the spindle 57 protruding from inside the crankcase 2, as in the known variable speed drive device. The shift drum 58 is rotated in stages through the shift drum 58, and at this time, each shift fork 60 is guided by the guide groove 58a of the shift drum 58 and slides on the shift fork shaft 59 in its axial direction, thereby changing the speed change gear train. Some transmission gears of 4 are connected to main shaft 5
Alternatively, by moving the subshaft 6 in the axial direction, the meshing combination of the transmission gear train 4 is changed, so that the rotation transmission from the main shaft 5 to the subshaft 6 is changed.

The spindle 57 is returned to its original position after being rotated a predetermined amount by a return spring 63 provided at an end inside the crankcase 2.

As shown in the first diagram, the generator 21 is rotatably mounted integrally with an end of the crank half-rest 28 of the crankshaft 1 protruding from inside the crankcase 2 on the side opposite to the clutch device 7. The stator 66 is fixed to the inner surface of a generator cover 65 attached to the crankcase 2 and housed in the flywheel 64, and the crankshaft 1 rotates like a known generator. At this time, the flywheel 64 rotates around the stator 66 together with the crankshaft 1 to generate electricity, thereby charging a battery (not shown).

The intake/exhaust device 19 includes a bearing 6 between the cylinder head l7 and the head cover 20 as shown in the first diagram.
7. The camshaft 69 includes a camshaft 69 that is rotatably supported via a camshaft 68, and a plurality of rocker arms 7l that are rotatably supported by a rocker arm shaft 70 that is provided on the head cover 20 in parallel with the camshaft 69. A cam driven gear 72 rotatably mounted integrally with the end of the generator 2
It is connected via a chain 74 to a cam drive gear 73 formed on the outer circumferential surface of the small diameter portion 28a of the clutch half-off 28 at a position between the crankshaft l and the crankcase 2, so that the camshaft '69 is connected to the crankshaft l. It will be recommended along with the rotation of the.

Each rocker arm 71 is engaged with a cam 69a formed on the camshaft 69, and an intake and exhaust valve (not shown) that opens and closes an intake and exhaust passage communicating with the combustion chamber l8.
is engaged with.

In this intake/exhaust device 19, similar to known engines,
The rotation of the camshaft 69 in synchronization with the crankshaft 1 opens and closes the intake and exhaust valves via the rocker arm 32, thereby performing intake and exhaust air into the combustion chamber 18. kick starter 2
Reference numeral 2 denotes a starter spindle 76 rotatably supported by the crankcase 2 and a clutch cover 75 attached to the crankcase 2, and an intermediate portion of the starter spindle 76 within the crankcase 2, as shown in FIG. The starter gear 76 is engaged with the driven gear 49 of the hollow shaft 48 having the secondary balancer 10, and the starter gear 77 is rotatably supported around the part. Is there a ratchet part on the end face? 7a is formed. At a position between the starter gear 77 and the clutch cover 75, a ratchet portion is fitted to the starter spindle 76 so as to be integrally rotatable and slidable. ? Drive ratchet 7 biased in the direction away from a
8 are provided. In such a kick starter 22,
By operating a kick pedal (not shown) connected to the starter spindle 76 outside the clutch cover 75, the drive ratchet 78 slides and connects the ratchet portion of the starter gear 77. ? a, the starter spindle 76 is rotated together with the drive ratchet 78, and the starter gear 77 is thereby rotated to rotate the hollow shaft 48.
is rotated. At this time, the hollow shaft 48 rotates in the same direction in conjunction with the crankshaft l as described above, thereby moving the piston 14 up and down and starting the engine.

The starter spindle 76 is returned to its original position after being rotated a predetermined amount by a return spring 79 provided at an end inside the crankcase 2 .

Next, in the engine of this configuration, the above-mentioned structure of the balancer device 8, which is a main part of the present invention, will be explained with reference to FIG.

In this balancer device 8, the primary balancer 9 and the secondary balancer 10 each have a hollow shaft 40. The earth shaft 5 and the sub-shaft 6 are rotatably provided to the main shaft 5 and the sub-shaft 6 via a shaft 48, and are used as these balancer shafts, and the other primary balancer l2 and secondary balancer 13 are Since it is rotatably provided on the balancer shaft l1 of the book, the number of dedicated balancer shafts can be reduced as much as possible.
The number of parts has been reduced.

The primary balancer 9 is interlocked with the crankshaft l via a hollow shaft 40 by a primary drive gear 37, a primary driven gear 38, and a clutch device 7, which are drive means for rotating the main shaft 5 of the transmission 3. Therefore, a dedicated drive means for rotating the primary balancer 9 is not required, and the number of parts of the balancer device 8 is reduced.

Further, by providing a drive gear 46 integrally between the primary balancer 9 and the clutch device 7 at both ends of the hollow shaft 40, the hollow shaft 40 is utilized spatially effectively, and the drive gear 46 By rotating the secondary balancer lO of the hollow shaft 48 on the secondary shaft 6, the hollow shaft 40
．． 48 is utilized effectively in terms of operation, and the number of parts dedicated to the balancer device 8 is reduced as much as possible.

Furthermore, since the primary balancer 9 and the clutch device 7 are provided at both ends of the hollow shaft 40, the rigidity of the hollow shaft 40 can be easily ensured by balancing the wits of both. , the hollow shaft 40 is made compact while ensuring sufficient rigidity, thereby reducing its weight and size.

Further, since the primary balancer 9 and the clutch device 7 are rotatable together and the gear ratio of the primary drive gear 37 and the primary driven gear 38 is 1:1, when the crankshaft 1 rotates, the clutch device The rotational torque applied to the clutch device 7 and the main shaft 5 is small, and therefore the strength required for the clutch device 7 and the main shaft 5 is reduced. Efforts are being made to make it lighter and lighter.

In this way, in the balancer device 8, the number of dedicated parts is reduced as much as possible, and the number of parts is significantly reduced. The construction parts of the system are effectively utilized spatially and operationally, and their weight and size are reduced.
Therefore, the engine is small and lightweight.

In addition, in the balancer device 8, the primary balancer 9 is connected to the hollow shaft 4.
0, and the clutch device 7 is spline-coupled to the hollow shaft 40. For example, the primary balancer 9
It goes without saying that the same effect as described above can also be obtained by spline-coupling the clutch device 7 to the hollow shaft 40 and integrating the clutch device 7 with the hollow shaft 40. According to the structure of this embodiment, as described in D below, the hollow shaft 40, the clutch device 7, etc. can be more easily assembled in the engine assembly work.

That is, in the engine of this embodiment, the crankcase 2
The connecting rod 30 is roughly divided into left and right parts on the rotating surface of the connecting rod 30, but the clutch device 7 and the hollow shaft 4
0, first, with the crankcase 2 on the clutch device 7 side removed, the hollow shaft 40, which is integrated with the primary balancer 9, is inserted onto the main shaft 5, and then, after installing the crankcase 2, the clutch device 7 to the hollow shaft 40 and main shaft 5. Further, even if the crankcase 2 is divided into upper and lower parts at the position of the main shaft 5, according to the structure of this embodiment, the clutch device 7 can be installed after the crankcase 2 is installed. , these can be assembled without any problems.

In this way, in the engine of this embodiment, the clutch device 7
, the hollow shaft 40 and the crankcase 2 can be assembled to the engine separately, making the assembly work relatively easy.

Next, a second example of the balancer device of the present invention will be described with reference to FIGS. 5 and 6. FIGS. 5 and 6 are explanatory sectional views of main parts of the engine as viewed from the side and from the front, respectively.

This engine has the same basic structure as the above-mentioned engine, and as shown in the fifth figure, a crankshaft 80 is connected to a piston 82 via a connecting rod 81, and as shown in the sixth figure, a generator is connected to both ends of the crankshaft 80. 83 and a primary drive gear 84 are provided. Then, as shown in Figure 6,
A main shaft 86 and a sub-shaft 87 of the transmission itf 85 are connected via a transmission gear train 88, a clutch device 89 is mounted concentrically at the end of the main shaft 86, and a clutch device 89 at the end of the main shaft 86 is connected. A hollow shaft 92 integrally provided with a primary balancer weight 91 (hereinafter referred to as primary balancer 91) of the balancer equipment ffi90 is provided at a position inside the balancer 89.

This hollow shaft 92 is one end of a cylindrical body 94 which is externally inserted concentrically with the end of the main shaft 86 and rotatably supported by the main shaft 86 via a twenty dollar bearing 93, as shown in FIG. It is fitted onto the outer circumferential surface of the section by spline connection, thereby making it rotatable around the main shaft 86 together with the cylindrical body 94. A clutch device 8 is provided at the other end of the cylinder 94.
Clutch outer 89a of No. 9 is fixed, so that hollow shaft 92 and clutch device 89 can rotate together around main shaft 86 via cylinder 94. Further, a primary driven gear 95 is provided integrally with the hollow shaft 92 and concentrically with the main shaft 86, and the primary driven gear 95 meshes with the primary drive gear 84 at a gear ratio of 1:1. .

In addition, in FIG. 5, 96. Numeral 96 is a shift fork that is engaged with a transmission gear train 88 (shown in the sixth figure) in the same way as the shift fork 60 of the transmission drive device 16.

Further, in FIG. 6, reference numeral 97 is a drive sprocket attached to the end of the subshaft 87 and connected to a wheel (not shown) via a chain 98; A drive gear 101 is provided on the crankshaft 80 for driving through the cylindrical body 94, and a driven gear 103 is engaged with a kick starter drive gear 102. 104 is a bearing that supports the middle portion of the cylindrical body 94, and a damper spring 104 is provided between the cylindrical body 94 and the tarlatch outer 89a. In such an engine, as the crankshaft 80 rotates as the piston 82 moves up and down, the primary driven gear 95, the hollow shaft 92, and the primary balancer 9l, which are integrally provided as described above, are connected to the main shaft 86 via the primary drive gear 84. At the same time, the clutch device 89 and the main shaft 86 are rotated about their axes via the cylinder 94, and the subshaft 87 is further rotated via the transmission gear train 88, so that the engine is rotated. Driving force is output to the wheels. At this time, the primary drive gear 84 and the primary driven gear 95 are engaged with each other at a gear ratio of 1:1, so the primary balancer 91, hollow shaft 92, clutch device 89, etc. rotate at the same speed as the crankshaft 80 in the opposite direction. This reduces the primary vibrations of the engine.

Therefore, similarly to the above engine, this engine does not require a dedicated drive means for rotating the primary balancer 91, and the number of parts of the balancer device 90 is reduced, and its weight and size can be reduced. It is planned.

Also, similar to the engine described above, the primary drive gear 8
4 and the primary driven gear 95 is 1:1, the rotational torque applied to the clutch device 89 and the main shaft 86 is small, and therefore the required strength of the clutch device 89 and the main shaft 86 is reduced, making it possible to downsize and It is designed to be lightweight.

Further, in this engine, the driven gear 101, a ball bearing 103, a damper spring 104, etc. are provided between the clutch device 89 and the primary driven gear 95, as shown in FIG. 6, so that space can be used effectively.

Next, a third example of the balancer device of the present invention will be explained according to the seventh diagram. Figure 7 is an explanatory cross-sectional view of the main parts of the engine. This engine has the same basic structure as the second example described above, and common features will be described with the same reference numerals as those of the engine of the second example.

That is, this engine includes a main shaft 86 of a transmission 85 having the same structure as the engine of the second example, a clutch device 89, a primary driven gear 95 connected to the clutch device 89 and a crankshaft (not shown), and a clutch device 89. Hollow shaft 92 and primary balancer 91 provided integrally with primary driven gear 95
It further includes a self-starter device 105 and an intermediate shaft 107 having a generator 106 attached to one end thereof, and the other end of the intermediate shaft 107 is connected to a first driven gear 95 and two pairs. It is connected to a clutch device 89 via a starter drive gear 108 that is engaged at a gear ratio of 1.

A starter clutch 109 of the self-starter device 105 is rotatably mounted approximately at the center of the intermediate shaft 107, and a drive gear 111 is connected to the starter motor 110.
and are connected via a driven gear 112.

Further, the balancer device 90 having the primary balancer 9l further includes a secondary balancer weight 1l3 (hereinafter referred to as secondary balancer ll3), and the secondary balancer 113 is integrally provided in the housing 109a of the starter clutch 109.

In such an engine, the self-starter device 105 rotates the intermediate shaft 107 via the drive gear 111, the driven gear 112, and the starter clutch 109 in order by the operation of the starter motor 110, and further rotates the intermediate shaft 107 through the starter drive gear 108,
The engine is started by rotating the crankshaft via the primary driven gear 95. When the engine is in operation, the rotation of the crankshaft causes the primary driven gear 95, the clutch device 89, and the starter drive gear 1 to be rotated.
08, the intermediate shaft 107 is rotated in turn. At this time,
Primary driven gear 95 and starter drive gear 108
Since the gear ratio of
3 is rotated together with the housing 109a of the starter clutch 109 at twice the speed of the crankshaft, thereby reducing secondary vibrations of the engine.

In this way, in this engine, the secondary balancer 113 is integrally provided with the housing 109a of the starter clutch 109, so that it can be rotated during engine operation, so a dedicated drive means is not required. Therefore, the number of parts of the balancer device 9o is reduced, and its weight and size are reduced. (Effects) As is clear from the above description, according to the balancer device for an internal combustion engine of the present invention, the balancer weight is integrally provided on the hollow shaft rotatably supported around the main shaft of the transmission, and the clutch device By providing the balancer weight integrally and rotatably, the balancer weight can be interlocked with the crankshaft using a drive means such as a clutch device for interlocking the main shaft with the crankshaft, and the balancer weight can be rotated. It is possible to reduce the number of parts that make up the balancer device without providing a dedicated drive means for the balancer device, thereby making it possible to reduce the weight and size of the engine.

Furthermore, at this time, since the main shaft of the transmission is rotated together with the clutch device at the same speed as the crankshaft, the rotational torque applied to the clutch device and the main shaft of the transmission is reduced.
Therefore, the strength required for the transmission and clutch devices is reduced, and they can be made smaller and lighter.

Furthermore, when the clutch device is connected to the crankshaft via the primary driven gear and the primary drive gear, the clutch device is connected to the hollow shaft from the crankshaft via the heavy clutch device that rotates together with the hollow shaft. Since the rotational force is transmitted, the hollow shaft is not twisted by the rotational force from the crankshaft, and its required strength is reduced. Furthermore, when a balancer weight and a clutch device are provided at both ends of a hollow shaft rotatably supported on the main shaft, the necessary rigidity of the hollow shaft can be easily achieved by balancing the weight of the balancer weight and clutch device. The balancer weight can be made compact, making it lightweight and compact, and the space between the balancer weight and the clutch device can be effectively utilized.

Furthermore, when the balancer weight is integrally provided at one end of the hollow shaft housed in the case, and the clutch device is fitted to the outer peripheral surface of the other end of the hollow shaft protruding outside the case, The balancer weight, case, and clutch device can be individually assembled to the internal combustion engine, and the assembly work can be easily performed. Further, when a drive gear for rotating another balancer weight is provided on the hollow shaft, the hollow shaft having the balancer weight can be effectively used as a drive means for rotating the other balancer weight, and The number of parts can be reduced without providing a dedicated drive means. Furthermore, when the other balancer weight is a secondary balancer weight, by simply connecting it to the hollow shaft via a pair of gears, the secondary balancer weight is linked to the crankshaft and the secondary balancer weight of the engine is vibration can be reduced.

Furthermore, when the primary balancer weight is rotatably provided between the secondary balancer weight and a driven gear provided integrally therewith, the space between the secondary balancer weight and the driven gear is By effectively shortening the length of both balancer weights and both gears in the direction of the main shaft, the structure of the balancer device can be made smaller, and the primary balancer weight and drive gear can be reduced in size. The main shaft that supports the engine can be shortened, and the internal combustion engine can be made smaller and lighter.

[Brief explanation of drawings]

1 to 3 are explanatory sectional views of main parts of an engine equipped with an example of the balancer device of the present invention in a front view, a plan view, and a side view, respectively, and FIG. 4 is an explanatory sectional view taken along the line The sectional views, FIGS. 5 and 6, respectively show the second part of the balancer device of the present invention.
FIG. 7 is an explanatory cross-sectional view of the main parts of an engine equipped with a third example of the balancer device of the present invention, as viewed from the side and from the front. l, 80...Crankshaft 2...Case 3.85
...Transmission device 4,88...Transmission gear train 5,8
6... Main shaft 6.87... Sub-shaft 7.89.
...Clutch device 8,90...Balancer device 9,9
l...Primary balancer weight 10. 113...
Secondary balancer weight 37. 84...Primary drive gear 38. 95...Primary driven gear 40.
92...Hollow shaft 46...Drive gear 49
...Driven gear FIG. 6 FIG. 7 Procedural amendment 1. Case Description 1999 Patent Application No. 150513 2. Name of the invention Balancer device for internal combustion engine 3. Patent applicant name: Honda Motor Co., Ltd. 46 Agent address: No. 6, 71-7, 2-chome Yoyogi, Shibuya-ku, Tokyo. Number of claims increased due to amendment 17. Claims column of the specification to be amended, detailed description of the invention8. Contents of amendment (1) The scope of claims in the specification is corrected as shown in the attached sheet. (2) After page 4, line 13 of the specification, it says, ``Furthermore, for chain-driven products, a tensioning mechanism (so-called chain tensioner) is required to prevent problems due to chain elongation, etc. Therefore, it is not preferable in this respect as well.'' is added. (2) After page 7, line 13 of the specification, add ``Furthermore, the secondary balancer weight is rotatably provided on the secondary shaft.'' (3) After page 10, line 8 of the specification, add ``Furthermore, since the secondary balancer weight can be placed close to the cylinder axis, it is advantageous to reduce the couple caused by the secondary balancer weight.'' (4) On page 19 of the specification, line 10, line 12-13, the phrase "at a position passing approximately the center between the two crank webs 23.24, that is," is replaced with "the crank web 23.24.
In other words, the position passes near the point O where the axial center of the cylindrical portion of the cylinder block 15 intersects with the axial center of the crankshaft orthogonal thereto.'' (5) On page 22, line 10 of the specification, ``cam driven gear j'' is corrected to ``cam driven subrocket.'' (6) On page 22 of the specification, line 13, ``cam drive gear'' is corrected to ``cam driven gear j.''"Cam drive sprocket" is corrected. c'? ) The phrase "rocker arm 32" on page 23, line 2 of the specification is corrected to "rocker arm 71." (8) After line 8 on page 24 of the specification, it is stated that ``In this embodiment, a kick starter is used, but a pulley is provided at the tip of the starter spindle 76 and a rope is wound around it multiple times, or a coil starter is used. Alternatively, a starter motor may be provided via an interlocking mechanism.'' is added. (9) “Drive gear” in lines 7 and 8 on page 30 of the specification should be corrected to “drive sprocket.” ”. As per the OD attachment, the drawings, Figures 1, 2, 3 and 7 are corrected. Scope of Claim ■. A main shaft that is interlocked with the crankshaft via a clutch device. In an internal combustion engine, the internal combustion engine includes a transmission device including a subshaft interlocked with the main shaft via a transmission gear, and a balancer device having at least a primary balancer weight that rotates in synchronization with the crankshaft. is integrally provided on a hollow shaft rotatably supported concentrically around the main shaft, and the clutch device is rotatably provided integrally with the hollow shaft, and is mounted on the crankshaft. A balancer device for an internal combustion engine, characterized in that the clutch device is connected to rotate at a constant speed and in an opposite direction.2. 3. The balancer device for an internal combustion engine according to claim 1, wherein the balancer weight is connected to the crankshaft via a primary drive gear provided on the crankshaft. 3. The balancer weight is connected to one end of the hollow shaft. 4. The balancer device for an internal combustion engine according to claim 1, wherein the clutch device is provided at the other end of the hollow shaft. 4. The balancer weight is provided at one end of the hollow shaft. The clutch device is integrally provided, the clutch device is fitted and connected to the outer circumferential surface of the other end of the hollow shaft, and one end of the hollow shaft where the balancer weight is provided is inside a case housing the transmission. Claim 1 characterized in that the clutch device is housed in the case and the other end portion that connects the clutch device projects outside the case.
Balancer device for the internal combustion engine described. 5. The balancer for an internal combustion engine according to claim 1, further comprising another balancer weight different from the primary balancer weight, and a drive gear for rotating the other balancer weight is provided integrally with the hollow shaft. Device. 6. The balancer device for an internal combustion engine according to claim 5, wherein the other balancer weight is a secondary balancer weight. 7. A driven gear provided integrally with the secondary balancer weight is meshed with the drive gear, and the primary balancer weight is rotatably provided between the secondary balancer weight and the driven gear. A balancer device for an internal combustion engine according to claim 6. 7 Nono Burnsa 11 (J FIG.7 89

Claims (1)

[Scope of Claims] 1. A transmission device consisting of a main shaft interlocked with the crankshaft via a clutch device and a subshaft interlocked with the main shaft via a transmission gear, which rotates at least in synchronization with the crankshaft. In an internal combustion engine equipped with a balancer device having a primary balancer weight, the balancer weight is integrally provided on a hollow shaft rotatably supported concentrically around the main shaft, and the clutch device is provided in the hollow shaft. A balancer device for an internal combustion engine, characterized in that the balancer device is provided on a shaft so as to be rotatable integrally therewith, and is connected to the crankshaft so as to rotate at the same speed and in the opposite direction. 2. A claim characterized in that the clutch device is connected to the crankshaft via a primary driven gear rotatably provided therewith and a primary drive gear provided on the crankshaft. Item 1: A balancer device for an internal combustion engine according to item 1. 3. The balancer device for an internal combustion engine according to claim 1, wherein the balancer weight is provided at one end of the hollow shaft, and the clutch device is provided at the other end of the hollow shaft. 4. The balancer weight is integrally provided at one end of the hollow shaft, the clutch device is fitted and connected to the outer peripheral surface of the other end of the hollow shaft, and the balancer weight of the hollow shaft is provided. 2. The balancer device for an internal combustion engine according to claim 1, wherein one end portion is housed in a case housing the transmission, and the other end portion connecting the clutch device projects outside the case. 5. The internal combustion engine according to claim 1, further comprising another balancer weight different from the primary balancer weight, and a drive gear for rotating the other balancer weight being integrally provided with the hollow shaft. balancer device. 6. The balancer device for an internal combustion engine according to claim 5, wherein the other balancer weight is a secondary balancer weight. 7. A driven gear provided integrally with the secondary balancer weight is meshed with the drive gear, and the primary balancer weight is rotatably provided between the secondary balancer weight and the driven gear. The balancer device for an internal combustion engine according to claim 6, characterized in that: