JP2003027956A - Assemblage structure for balancer device, and balancer device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide an assemblage structure for a balancer device capable of continuously and more simply conducting gap adjustment between a drive gear provided on a crankshaft and a driven gear engaged with it to transmit rotation of it to a balance shaft. SOLUTION: In this assemblage structure, a guide protruded part 221 provided on an upper surface of a balancer housing 211 and a guide recessed part 113 provided in a bottom part of a cylinder block 110 are engaged with each other to form a slide mechanism 218. In a flange part 222 of the balancer housing 211, a slit 223 having a longer diameter in the guide direction of the slide mechanism 218 is provided. After adjusting engagement between the drive gear 112 and the first driven gear 214 while moving the balancer housing 211 through the slide mechanism 218, a bolt 310 is engaged with a bolt hole 114 through the slit 223, thereby the balancer housing 211 can be fastened and fixed to the cylinder block 110.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a balancer device for eliminating an inertial force or an inertial couple due to a piston, a connecting rod or the like of an internal combustion engine to damp an output vibration of the engine, and particularly to the internal combustion engine. Assembling structure to the engine,
And a balancer device having a structure suitable for realizing the assembly structure.

[0002]

2. Description of the Related Art Conventionally, as this type of balancer device,
For example, the structure shown in FIGS. 6 and 7 is known.
Here, FIG. 6 is a side cross-sectional view showing the manner of engagement with this crankshaft as the balancer device, including the crankshaft that is the output shaft of the internal combustion engine, and FIG. It is a front sectional view which followed the line.

As shown in FIGS. 6 and 7, the internal combustion engine is provided with a crankshaft 61 for taking out rotational power obtained by converting the reciprocating motion of the piston into rotational motion via a connecting rod. In general, a balancer device 63 is attached below a cylinder block (only the bottom portion thereof is shown) 62 that axially supports the crankshaft 61 while being engaged with the crankshaft 61.

By the way, the crankshaft 61 is
A crank journal 611 which is a part pivotally supported by the cylinder block 62, a crank pin 612 which is a part connected to the connecting rod, a crank arm 613 which supports the crank pin 612, and a counterweight 614 which is a balancer of the crankshaft 61 itself. And so on.

A drive gear 615 is attached to an intermediate portion of the crankshaft 61 so as to rotate integrally with the crankshaft 61.
The above crankshaft 6 receives the rotational power of
The engagement between 1 and the balancer device 63 is maintained.

The balancer device 63 is provided with a first balance shaft 632 and a second balance shaft 633, which are arranged in parallel and rotatably supported in the balancer housing 631. Then, a first driven gear 634 and a first balance weight 635, which are meshed with the drive gear 615, are externally fitted onto the first balance shaft 632 so as to be integrally rotatable. Further, a second driven gear 636 and a second balance weight 637 which are meshed with the first driven gear 634 are externally fitted to the second balance shaft 633 (FIG. 7) so as to be integrally rotatable. There is.

The first driven gear 634 and the second driven gear 63 are in mesh with the drive gear 615.
Some gears are configured as separate gears from the portion meshed with 6, but in FIGS. 6 and 7, for convenience, a gear in which these respective portions are integrated is illustrated.

The balancer device 63 is basically arranged as described above on the lower surface of the cylinder block 62.
As shown in FIG. 5, the bolts 638 are fastened and fixed to the cylinder block 62.

By providing the balancer device 63 as described above, the rotation of the crankshaft 61 due to the operation of the internal combustion engine is sequentially transmitted from the first driven gear 634 to the second driven gear 636. Balance shaft 6
32, 633 each balance weight 63 fitted on the outside
The output vibration of the engine can be damped according to the shape, mass, rotational phase, and the like of 5, 637.

[0010]

By the way, in such a balancer device, increasing the meshing accuracy of the drive gear 615 and the first driven gear 634 ensures the damping performance of the output vibration and causes backlash. This is effective in suppressing gear rattling noise during idling.

Therefore, conventionally, in order to improve the meshing precision between these gears, a gap adjusting member 64 such as a shim is provided on the mounting surface of the cylinder block 62 and the balancer device 63, as shown in FIG. The clearance between the mounting surfaces of the cylinder block 62 and the balancer device 63, and hence the clearance between the drive gear 615 and the first driven gear 634 is adjusted.

However, such a gap adjusting member 6
In the gap adjustment using No. 4, only the stepwise adjustment limited to the thickness of the gap adjusting member 64 can be performed, and the adjustment itself cannot be performed at an interval smaller than the thickness of one rank of the gap adjusting member 64. It is an inefficient and accurate problem.

Conventionally, as disclosed in, for example, Japanese Patent No. 2811968, there is a structure in which the shaft center of the driven gear can be eccentrically arranged to solve the above problems.
In this case, structural complication is unavoidable.

The present invention has been made in view of the above circumstances, and an object thereof is to adjust a gap between a drive gear provided on a crankshaft and a driven gear meshed with the drive gear for transmitting the rotation thereof to a balance shaft. Assembling structure of the balancer device that can perform the operation continuously and more easily,
Another object of the present invention is to provide a balancer device having a structure suitable for realizing the assembly structure.

[0015]

[Means for Solving the Problems] Means for achieving the above-mentioned objects and their effects will be described below. According to a first aspect of the present invention, there is provided a balance shaft which has a balance weight and is rotatably supported by the housing, and a drive provided on the crank shaft for transmitting the rotation of the crank shaft of the internal combustion engine to the balance shaft. In a structure for assembling a balancer device, comprising: a driven gear meshed with a gear, wherein the housing is assembled with a cylinder block of the engine in such a manner that the meshing of the gears is maintained in a predetermined manner. The contact surface has guide means for selectively guiding relative movement of the housing and the cylinder block in a direction in which the axial distance between the crankshaft and the balance shaft is changed, and the crank is provided via the guide means. The housing is adjusted with the distance between the shaft and the balance shaft adjusted. Grayed is summarized in that made is fastened to the cylinder block.

According to the invention of claim 5, a balance shaft having a balance weight and rotatably supported by the housing, and the crank shaft for transmitting the rotation of the crank shaft of the internal combustion engine to the balance shaft. A balancer device comprising: a driven gear meshing with a drive gear provided on the housing, the housing being assembled to a cylinder block of the engine such that the meshing of the gears is maintained at a predetermined level. The gist of the present invention is to provide guide means for selectively guiding the movement of the housing in the direction in which the axial distance between the crankshaft and the balance shaft is changed, on the contact surface.

According to the assembling structure of the balancer device or the balancer device, the drive gear and the driven gear are moved by a simple work of moving the housing along the guide means provided on the contact surface between the housing and the cylinder block. The gap can be adjusted, and also the gap can be adjusted continuously. For this reason, the meshing of the drive gear and the driven gear can be realized with higher accuracy than in the case of using the conventional gap adjusting member or the like, although the structure is extremely simple.

According to a second aspect of the invention, in the assembly structure of the balancer device according to the first aspect, the guide means is
The gist of the present invention is that the slide mechanism is engaged and recessed so as to selectively allow relative movement of the housing and the cylinder block in the direction of changing the axial distance between the crankshaft and the balance shaft.

According to a sixth aspect of the present invention, in the balancer device according to the fifth aspect, the guide means moves the housing in a direction that changes an axial distance between the crankshaft and the balance shaft. The gist is that it is one of the slide mechanisms that are engaged in a concave and convex shape to allow selectively.

According to these assembling structures or balancer devices, since the guide means is formed as a slide mechanism in which the housing and the cylinder block are engaged in concave and convex, the function as the guide means, that is, the balance with the crankshaft. The selective guiding function in the direction of changing the axial distance from the shaft can be easily and accurately realized.

According to a third aspect of the present invention, in the structure for assembling the balancer device according to the second aspect, the slide mechanism has a concave portion formed on the cylinder block side and a convex portion formed on the housing side. It is a summary.

The invention according to claim 7 is the balancer device according to claim 6, wherein the guide means is formed as a convex portion of the slide mechanism. According to these assembling structures or the balancer device, the convex portion forming the slide mechanism is formed on the housing side of the balancer device which is smaller and lighter than the cylinder block, and since the convex portion is normally placed upward, It also becomes possible to preferably avoid damage or the like before assembling the convex portion.

According to a fourth aspect of the present invention, there is provided the balancer device mounting structure according to any one of the first to third aspects,
The balancer device has a flange on a part of the contact surface of the housing with the cylinder block, and a bolt hole for fastening is formed in this flange, and the bolt hole has a major axis in the guide direction of the guide means. The gist is that it is formed as a long hole that forms.

The invention according to claim 8 is the invention according to claims 5 to 7.
In the structure for assembling the balancer device according to any one of 1 to 3, the housing has a flange in a part of a contact surface with the cylinder block, and a bolt hole for fastening with the cylinder block is formed in the flange. The gist is that the bolt hole is formed as a long hole having a long diameter in the guide direction of the guide means.

According to these assembling structures or balancer devices, after adjusting the gap between the driving gear and the driven gear,
The balancer device (correctly, its housing) can be bolted to the cylinder block at any position within the range of the major axis of the bolt hole.

[0026]

BEST MODE FOR CARRYING OUT THE INVENTION An embodiment of the present invention will be described below with reference to FIGS. First, an outline of an assembling structure of a balancer device according to the embodiment will be described with reference to FIGS. 1 and 2. Note that FIG.
2 shows a side structure of the balancer device assembled to the cylinder block of the internal combustion engine, and FIG. 2 shows a planar structure of the balancer device.

As shown in FIG. 1, a crankshaft 111 is rotatably supported by a cylinder block 110 of an internal combustion engine, and is engaged with a drive gear 112 provided on the crankshaft 111. The balancer device 210 is attached to the bottom surface of the cylinder block 110. The balancer device 210 includes a balancer housing 211, balance weights 212,
A first and a second balance shafts 213 and 215 having a rotary shaft 217 and rotatably supported by the rotary shaft 217 are provided.
Of these, the first driven gear 214 that meshes with the drive gear 112 is attached to the first balance shaft 213.
However, the second driven gear 216 meshed with the first driven gear 214 is externally fitted to the second balance shaft 215.

The abutment surfaces of the balancer housing 211 and the cylinder block 110 are moved relative to each other by the uneven engagement, that is, the balancer housing 211 and the cylinder block 110, that is, the first balance shaft 213 and the crankshaft. A slide mechanism 218 is provided that selectively guides relative movement in a direction in which the axial distance from 111 is changed. The first driven gear 214 provided on the first balance shaft 213 and the drive gear 112 provided on the crankshaft 111 are
The gap is adjusted through the slide mechanism 218, and the balancer housing 211 is fastened to the bottom surface of the cylinder block 110 by the bolts 310 in a state where the gears are properly meshed during the above-mentioned assembly.

Next, the cylinder block 110 in the above-described mode.
The internal structure of the balancer device 210 attached to the lower surface of the will be described with reference to FIG. As shown in FIG. 2, the first balance shaft 213 and the second balance shaft 215 are rotatably supported in parallel and rotatably on the balance shaft support walls 219 and 220 of the balancer housing 211. . Of these, the first balance shaft 213 has the first driven gear 214.
And the first balance weight 212, and the second balance shaft 215 has a second driven gear 216 meshed with the first driven gear and a second balance weight 21.
7 are externally fitted so as to be integrally rotatable. That is, since the rotation of the crankshaft 111 is transmitted to the first driven gear 214 via the drive gear 112, the rotation is further transmitted from the first driven gear 214 to the second driven gear 216. The 1st and 2nd balance shafts 213 and 215 follow and rotate. By rotating the balance weights 212, 217 integrally with the balance shafts 213, 215, the engine output vibration can be reduced.

Further, on the upper surface of the balancer housing 211, as a part of the slide mechanism 218, a guide recess 113 provided at the bottom of the cylinder block 110.
A guide protrusion 221 that engages with (FIG. 1) is formed.
The balancer housing 211 is attached to the cylinder block 11 so that the guide concave portion 113 and the guide convex portion 221 are engaged with each other.
The balancer housing 21
The direction in which 1 can move relative to the cylinder block 110 is the direction in which the axial distance between the crankshaft 111 and the first balance shaft 213 is changed, that is, in FIG.
The directions are limited to the directions of arrows GR and GE. Therefore, the drive gear 112 and the first driven gear 2
The balancer housing 211 also adjusts the meshing state with
It is extremely easy to simply slide through the slide mechanism 218 in the directions of the arrows GR and GE.

Further, a flange portion 222 for fastening is formed on the contact surface of the balancer housing 211 with the cylinder block 110. The flange 222 has a long hole 2 having a long diameter in the sliding direction of the slide mechanism 218 at a position corresponding to the bolt hole 114 (FIG. 1) formed in the bottom of the cylinder block 110.
23 is formed. That is, the balancer housing 211 is moved from the arrow GE side (gap enlargement side) to the arrow GR side (gap reduction side) through the slide mechanism 218 within the range of the long diameter of the long hole 223 to move the first driven gear. A gap between the 214 and the drive gear 112 (FIG. 1) can be adjusted.

Next, the cylinder block 110 of the internal combustion engine
The assembling procedure of the balancer device 210 with respect to the above will be described in more detail with reference to FIGS. Each of these figures corresponds to a sectional view taken along the line D-D in FIG. 1.

In this assembling, first, as shown in FIG. 3, the balancer housing 211 is arranged at a position where the driving gear 112 and the first driven gear 214 are not in contact with each other,
The guide projection 221 of the balancer housing 211 and the guide recess 11 formed at the bottom of the cylinder block 110.
3 and 3 are engaged. As a result, the slide mechanism 218 is formed, and the balancer housing 211 is guided in the guide direction,
That is, it can be selectively moved in a slidable direction.

The balancer housing 21 thus arranged
Next, 1 is moved from the arrow GE side (gap expansion side) to the arrow GR side (gap reduction side) until the drive gear 112 and the first driven gear 214 contact each other. At the same time, while rotating the crankshaft 111, the current gap between the drive gear 112 and the first driven gear 214 is continuously adjusted, so that backlash does not occur as shown in FIG. The adjustment ends at the position.

Finally, as shown in FIG. 5, with the gap between the gears adjusted, the flange 2
The bolt 310 is screwed into the bolt hole 114 in which the internal thread is cut through the elongated hole 223 of 22 to fasten and fix the balancer housing 211 to the cylinder block 110.

As described above, in the present embodiment, the gap between the drive gear 112 and the first driven gear 214 is adjusted by moving the balancer housing 211 from the arrow GE to the arrow GR under the guidance of the slide mechanism 218. The cylinder block 110 is fastened to the cylinder block 110 easily and surely by adopting the elongated hole 223.

As described in detail above, according to the assembling structure of the balancer device or the balancer device according to this embodiment, the following excellent effects can be obtained.

(1) Simply moving the balancer device 210 along the slide mechanism 218 formed by the guide protrusion 221 provided on the balancer housing 211 and the guide recess 113 provided on the bottom of the cylinder block 110. It is possible to adjust the gap (engagement mode) between the drive gear 112 and the first driven gear 214 through such a mechanism.

(2) Since the conventional gap adjusting member is not necessary and the gap (meshing mode) between the gears can be continuously adjusted, the gap accuracy (meshing accuracy) can be further improved. You can

(3) Guide recess 113 and guide protrusion 22
When 1 is engaged, the movable direction of the balancer housing 211 is limited to the direction in which the axial distance between the crankshaft 111 and the first balance shaft 213 is changed. Therefore, the drive gear 112 and the first driven gear 2
The positioning operation of the balancer housing 211 for adjusting the meshing with 14 and for fastening to the bolt 310 is also facilitated.

(4) Since the guide protrusion 221 forming the slide mechanism 218 is formed on the balancer housing 211, which is smaller and lighter than the cylinder block 110, and this protrusion is normally placed upward. Therefore, it is possible to preferably avoid damage or the like before assembling the convex portion.

(5) Since the bolt hole formed in the balancer housing 211 is the elongated hole 223, after adjusting the gap between the drive gear 112 and the first driven gear 214, the bolt is attached to the cylinder block 110 of the balancer housing 211. Fast and easy fastening.

The assembly structure of the balancer device or the balancer device according to the present invention is not limited to the above-mentioned embodiment, and the embodiment can be appropriately modified, for example, realized as the following forms. You can also

In the above embodiment, the slide mechanism 21
8, the guide recess 1 is provided at the bottom of the cylinder block 110.
13. The guide convex portions 221 are formed on the balancer housing 211, but the arrangement relationship of the concave portions and the convex portions may be reversed as long as damage to the convex portions before assembly can be avoided.

In the above embodiment, the slide mechanism 21
Although two sets of concave and convex engagements are used as 8, the concave and convex engagements may be one set or three or more sets. In the above embodiment, the guide concave portion 113 and the guide convex portion 22
Although the slide mechanism 218 is formed by 1 and 1, the shape thereof is not limited to unevenness. For example, the slide mechanism may be formed by a substantially triangular protrusion and a groove or the like that engages with the protrusion.

In the above embodiment, the balancer housing 211 and the cylinder block 110 are processed to form the slide mechanism 218 that engages with the concave and convex portions. However, either or both of the balancer housing 211 and the cylinder block 110 are formed. The slide mechanism may be formed by assembling a separate rail member or the like and engaging the rail member or the like.

In the above embodiment, the slide mechanism 21
Although the relative movement of the balancer housing 211 with respect to the cylinder block 110 is guided by 8, the mechanism or the like is not limited to this. In short, these balancer housing 211 and cylinder block 11
The mechanism or the like is arbitrary as long as it can guide relative movement in the direction of changing the axial distance between the crankshaft 111 of 0 and the first balance shaft 213 in a mode that selectively guides the relative movement.

The arrangement position of such guide means is also
The position is not limited to the position exemplified in the above-mentioned embodiment, and may be arbitrary. In the above-described embodiment, the portion that meshes with the drive gear 112 as the first driven gear 214 and the second driven gear 216.
It is assumed that the gear is integrally formed with the part that is meshed with, but the structure is arbitrary. For example, those drive gears 1
A part in which the part meshed with 12 and the part meshed with the second driven gear 216 are separately configured via an appropriate damper mechanism or the like can be appropriately adopted.

The balancer device itself and the structure for attenuating the vibration of the crankshaft 111 are arbitrary including the rotation transmission structure and the number of balance shafts. In short, (a) a balance shaft that has a balance weight and is rotatably supported by a housing, and a drive gear that is provided on the crank shaft for transmitting the rotation of the crank shaft of the internal combustion engine to the balance shaft. And a driven gear that is meshed.

(B) For example, as shown in the sectional views of FIGS. 3 to 5, the line segment connecting the crankshaft and the balance shaft is not 90 ° with respect to the contact surface between the cylinder block and the housing. It is assembled at an angle, that is, at an acute angle or an obtuse angle. The present invention can be applied to any assembling structure or balancer device satisfying the above conditions, and the application of the present invention makes it possible to obtain the operational effects according to the above-described embodiment.

[Brief description of drawings]

FIG. 1 is a side view schematically showing a side structure of an embodiment of an assembly structure of a balancer device according to the present invention.

FIG. 2 is a plan view showing a planar structure of a balancer device according to the same embodiment.

FIG. 3 is a schematic front view showing the assembling procedure of the same embodiment (corresponding to a sectional view taken along line D-D in FIG. 1).

FIG. 4 is a schematic front view showing the assembling procedure of the same embodiment (corresponding to a sectional view taken along line D-D in FIG. 1).

FIG. 5 is a schematic front view showing an assembling procedure of the same embodiment (corresponding to a sectional view taken along line D-D in FIG. 1).

FIG. 6 is a partial side sectional view showing an example of an assembling structure of a conventional balancer device.

7 is a cross-sectional view taken along the line AA of FIG.

[Explanation of symbols]

110 ... Cylinder block, 111 ... Crank shaft, 112 ... Drive gear, 113 ... Guide recess, 210 ... Balancer device, 211 ... Balancer housing, 212 ... First balance weight, 213 ... First balance shaft, 214 ... First Driven gear, 215 ... second balance shaft, 216 ... second driven gear, 217 ... second balance weight, 218 ... slide mechanism, 221 ... guide protrusion, 222 ... flange portion, 223 ... elongated hole.

Claims (8)

[Claims] 1. A balance shaft, which has a balance weight and is rotatably supported by a housing, and a drive gear provided on the crank shaft for transmitting rotation of a crank shaft of an internal combustion engine to the balance shaft. In the assembly structure of the balancer device, wherein the housing is assembled to the cylinder block of the engine in such a manner that the meshing of the gears is maintained at a predetermined level, a contact surface between the housing and the cylinder block is provided. ,
It has guide means for selectively guiding the relative movement of the housing and the cylinder block in the direction of changing the axial distance between the crankshaft and the balance shaft, and the crankshaft and the balance through the guide means. An assembling structure of a balancer device, wherein the housing is fastened to the cylinder block in a state where an axial distance from the shaft is adjusted. 2. A slide mechanism in which the guide means is engaged and recessed to selectively allow relative movement of the housing and the cylinder block in a direction of changing an axial distance between the crankshaft and the balance shaft. The balancer device assembly structure according to claim 1. 3. The assembly structure of the balancer device according to claim 2, wherein the slide mechanism is provided with a concave portion on the cylinder block side and a convex portion on the housing side. 4. The balancer device has a flange on a part of a contact surface of the housing with the cylinder block, and a bolt hole for fastening is formed in the flange, and the bolt hole is the guide means. The assembly structure of the balancer device according to any one of claims 1 to 3, which is formed as a long hole having a long diameter in the guide direction. 5. A balance shaft, which has a balance weight and is rotatably supported by a housing, and a drive gear provided on the crank shaft for transmitting the rotation of the crank shaft of the internal combustion engine to the balance shaft. And a driven gear, wherein the housing is assembled to the cylinder block of the engine so that the meshing of the gears is maintained at a predetermined level, in a contact surface of the housing with the cylinder block,
A balancer device comprising guide means for selectively guiding movement of the same housing in a direction in which an axial distance between the crankshaft and the balance shaft is changed. 6. The guide means is one of a slide mechanism engaged in a concave and convex shape to selectively allow movement of the housing in a direction of changing an axial distance between the crankshaft and the balance shaft. The balancer device according to claim 5. 7. The balancer device according to claim 6, wherein the guide means is formed as a convex portion of the slide mechanism. 8. The housing has a flange on a part of a contact surface with the cylinder block, and a bolt hole for fastening with the cylinder block is formed in the flange, and the bolt hole is formed by the bolt hole. 8. The balancer device assembling structure according to claim 5, which is formed as a long hole having a long diameter in the guide direction of the guide means.