JPH0791273A - Multi-cylinder engine accessory drive - Google Patents

Abstract

(57) [Summary] (Modified) [Purpose] Reduction of metal hammering noise and impact force in V-type engines and horizontally opposed engines in which one cylinder row (bank) and the other cylinder row (bank) are offset. To improve engine reliability. An accessory drive device for a multi-cylinder engine in which an accessory drive means 18 including a pulley for driving a plurality of accessories by a driving force of a crankshaft and accessory drive belts 26, 33 is provided at an engine end. Between the cylinder rows of one cylinder row B1 in which the first cylinder exists and the other cylinder row B2 in which the second cylinder exists, and on the side far from the accessory drive means 18, the second cylinder row Auxiliary machines 6 and 24 having a large inertia are respectively arranged outside the bank B2 on the side where the axes exist, and the auxiliary machine driving belts 26 and 33 are moved by the auxiliary machines 6 and 24 having a large inertia. Synthetic power F3
However, it is arranged so as to be directed to the bank B2 on the side where the second cylinder is present.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to, for example, a V-type engine in which an auxiliary machine drive means including a pulley for driving a plurality of auxiliary machines by a driving force of a crankshaft and an auxiliary machine drive belt is provided at an engine end. And an accessory drive device for a multi-cylinder engine such as a horizontally opposed engine.

[0002]

2. Description of the Related Art Conventionally, as an auxiliary machine driving apparatus for a multi-cylinder engine of the above-mentioned example, there is an apparatus described in JP-A-60-230503. That is, in a V-type engine, a crank pulley connected to the tip of the crankshaft is provided at the engine end, and one accessory drive belt is wound between this crank pulley and one bank drive accessory drive pulley. It is a device in which the auxiliary device driving belt is wound around the above-mentioned crank pulley and the bank-side auxiliary device driving pulley on the other side, and the auxiliary device driving means is arranged at the end portion of the engine. .

In the case where the respective auxiliary machines are arranged so that the dynamic synthetic force generated during the rotation of the two auxiliary machine drive belts is directed in the cylinder axis direction in the bank on which the first cylinder is present. However, the following problems occur.

That is, since the rear end side of the crankshaft is pivotally supported on the transmission side and is in a cantilever state, the front end side of the crankshaft has a structure that is more swayable than the rear end side. Since the above-mentioned dynamic synthetic force acts on this crankshaft tip side, the crankshaft tip side, which is prone to shaking, is temporarily lifted up by this dynamic synthetic force, and the first journal of the crankshaft and this first journal are When the clearance between the bearing and the first metal of the upper and lower half-split structure becomes large, and the explosion pressure acts on the piston, the crank shaft once lifted is pressed downward,
The larger the metal clearance is, the louder the metal hammering sound is, and the impact force of the metal hitting the lower block lowers the reliability of the engine.

In order to solve such a problem, if the metal clearance between the first crank journal of the crankshaft and the first metal is set to be small, the tip end of the crankshaft is Due to the great shaking,
There is a problem that seizure of No. 1 metal occurs due to the stress acting to regulate the shaking.

[0006]

According to a first aspect of the present invention, one cylinder row (bank) in which the first cylinder is present and the other cylinder row (bank) in which the second cylinder is present are offset. In the V-type engine and the horizontally opposed engine, the burning force is configured by directing the dynamic synthetic force generated during the rotation of the accessory drive belt to the bank on the side where the second cylinder is present. The load acting on the 1st journal, which is unfavorable to the attachment, is directed to the bank on the side where the 2nd cylinder exists as a different direction with the existing auxiliary machinery and the belt for driving the auxiliary machinery to reduce metal hammering noise and impact force. It is an object of the present invention to provide an auxiliary machine drive device for a multi-cylinder engine that can be alleviated to improve engine reliability.

According to a second aspect of the present invention, in addition to the object of the first aspect of the invention, a metal bearing a second journal having a smaller crankshaft swing than the first journal described above. By setting the clearance of 2 to be smaller than the metal clearance of other parts, it is possible to reduce the stroll when an impact force is generated, prevent seizure of the 2nd metal, and improve durability and reliability. An object of the present invention is to provide an accessory drive device for a multi-cylinder engine.

According to the invention of claim 3 of the present invention, in addition to the object of the invention of claim 1 or 2, the auxiliary having a large inertia on the bank side offset toward the crankshaft rear end direction side in the crankshaft direction. A machine is arranged, and the above-mentioned dynamic synthetic force is generated by the auxiliary machine and the belt for driving the auxiliary machine.
Auxiliary machine drive device for a multi-cylinder engine configured so as to be directed to the bank on the side where the cylinders are present so that the load acting on the first journal, which is disadvantageous to seizure, can be better directed in another direction For the purpose of providing.

[0009]

According to a first aspect of the present invention, an accessory driving means including a pulley for driving a plurality of accessories by a driving force of a crankshaft and an accessory driving belt is an engine end portion. An auxiliary machine drive device for a multi-cylinder engine, wherein one of the cylinder rows in which the first cylinder exists and the second cylinder row
Auxiliary machines having a large inertia are provided between the cylinder row with the other cylinder row in which the cylinders are present and outside the bank on the side where the second cylinder is present, which is located far from the auxiliary machine drive means. Auxiliary machines for a multi-cylinder engine, which are arranged so that the dynamic synthetic force of the auxiliary machine drive belt is directed to the bank on which the second cylinder is present by the auxiliary machines having large inertia. It is a drive device.

According to a second aspect of the present invention, in addition to the configuration of the first aspect of the invention, the clearance of the metal bearing the second journal of the crankshaft is set to be smaller than other portions. It is characterized in that it is an accessory drive device for a multi-cylinder engine.

According to the invention of claim 3 of the present invention, in addition to the structure of the invention of claim 1 or 2, the inertia is large on the bank side offset toward the crankshaft rear end direction side in the crankshaft direction. It is characterized in that it is an accessory drive device for a multi-cylinder engine in which accessories are arranged.

[0012]

According to the invention described in claim 1 of the present invention, the bank on the side where the second cylinder is present is located on the side far from the accessory drive means arranged at the above-mentioned engine end portion. Inertia (iner)
tia (inertia) has a large auxiliary machine, and the dynamic combined force of the auxiliary machine drive belt is directed to the bank on the side where the above-mentioned second cylinder exists by each auxiliary machine having a large inertia. Since it is arranged, the load acting on the first journal, which is disadvantageous to seizure, can be directed to the bank on the side where the second cylinder exists as a different direction with the existing auxiliary machine and the belt for driving the auxiliary machine, There is an effect that the reliability of the engine can be improved by reducing the metal hammering sound and the impact force.

That is, the second cylinder exists in the bank farther from the accessory drive means, and the second journal of the crankshaft corresponding to the second cylinder is compared with the first journal described above. Since there is little swing of the crank shaft, there is an effect that the metal tapping noise can be reduced by the amount of the swing of the crank shaft being small.

According to the invention of claim 2 of the present invention,
In addition to the effect of the invention described in claim 1, the clearance of the metal bearing the second journal of the crankshaft is set to be smaller than the metal clearance of the other parts. The No. 2 journal and No. 2 metal, which are prone to metal tapping due to both explosive pressure and
It is possible to reduce the stroke when an impact force is generated between the No. metal and the second metal, while preventing seizure of the No. 2 metal, the stroke is narrowed to reduce the impact force, and durability and reliability are improved. There is an effect that can be improved.

According to the invention of claim 3 of the present invention,
In addition to the effect of the invention described in claim 1 or 2, since the auxiliary machine having large inertia is arranged on the bank side offset toward the crankshaft rear end direction side in the crankshaft direction, the auxiliary machine having large inertia is arranged. The above-mentioned dynamic combined force is directed to the bank on the side where the second cylinder is present by means of the machine and accessory drive belts.

As a result, there is an effect that the load acting on the first journal, which is disadvantageous to seizure, can be more favorably directed in the other direction.

[0017]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of the present invention will be described in detail below with reference to the drawings. The drawing shows the accessory drive of a multi-cylinder engine,
1, 2, and 3, the cylinder heads 2 and 3 and the cylinder head covers 4 for the banks B1 and B2 are provided above the cylinder block 1 in the V-type 6-cylinder engine.
5, a Risholum compressor 6 having a relatively large inertia as a mechanical supercharger driven by an engine is arranged between the V banks.

In this embodiment, the above V-6 engine is set to a valve timing at which the effective compression ratio is smaller than the effective expansion ratio. In detail, a typical intake late closing is 50 to 55 degrees after ABDC (after bottom dead center, after bottom dead center), whereas the intake valve closing timing of this V-6 engine is ABDC 70 degrees. And a vacuum pump 7 for generating negative pressure is provided for the purpose of compensating for the load shortage.

Here, the above-mentioned one-side bank B1 has a first cylinder CY1, a third cylinder CY3 and a fifth cylinder CY5 as clearly shown in FIG. 2, and the above-mentioned other-side bank B2 is a second cylinder C2.
Y2, the fourth cylinder CY4, and the sixth cylinder CY6 are provided, and the other bank B2 is offset from the one bank B1 by a distance L toward the crankshaft rear end direction in the crankshaft (see FIG. 3) direction. ing.

As shown in FIG. 3, the above-mentioned crankshaft 8 has a number of cylinders, that is, a total of six crankpins P1 to P6,
A total of four journals J1, J2, J3 and J4 are provided, and the crank pins P1 to P6 described above are connected to the pistons 10 of the respective cylinders via the connecting rods 9 ... Pistons are omitted) and each of the above-mentioned journals J1
~ J4 is each metal M1, M2, M3 of upper and lower half structure
It is rotatably supported by each bearing 12 ... of the lower block 11 via M4.

A small-diameter first crank pulley 13, a medium-diameter second crank pulley 14, and a large-diameter third crank pulley 15 are fitted and fixed to the tip of the crankshaft 8 while the crankshaft is A flywheel 17 having a ring gear 16 is attached to the rear end of the wheel 8.

By the way, accessory drive means 18 for driving a plurality of engine accessories (a vacuum pump, an alternator, a compressor for an air conditioner, a power steering pump, a reservoir compressor, a water pump) by the driving force of the crankshaft 8 described above. Is provided at the engine end.

That is, the above-mentioned third crank pulley 15
And the tensioner pulley 20 of the auto tensioner 19,
The belt for driving the first auxiliary device is provided between the driving pulley 21 of the vacuum pump 7, the driving pulley 23 of the alternator 22, and the driving pulley 25 of the compressor 24 for the air conditioner as an engine auxiliary device having a large inertia. On the other hand, the second crank pulley 14, the tensioner pulley 28 of the auto tensioner 27, the power steering pump driving pulley 29, the pulley 30 for driving the lishorum compressor 6, and the water pump 31 are wound around 26.
Second auxiliary drive belt 33 between the drive pulley 32 and
And the respective engine auxiliaries of the banks B1 and B2 are driven by the above-mentioned two accessory driving belts 26 and 33.

Compressor 24 for the air conditioner described above
As is clear from the drawings, the two are arranged in the bank B2 on the other side, which is offset toward the crankshaft rear end direction in the crankshaft direction. A compressor 24 arranged on the side far from the accessory drive means 18 and outside the bank B2 on the side where the second cylinder CY2 exists;
Both the first and second auxiliary machine drive belts 26, 26 by the Risholum compressor 6 arranged between the banks,
The dynamic combined force F3 of 33 is configured to be directed to the bank B2 on the side where the second cylinder CY2 is present.

That is, in this embodiment, the resultant force F1 of the first accessory drive belt 26 is as shown in FIG. 1, and the resultant force F2 of the second accessory drive belt 33 is as shown in FIG. , F2 is a further resultant force (dynamic combined force) F3,
It is directed in the cylinder axis X direction of the other bank B2.
In FIG. 1, Y indicates the cylinder axis of the one-side bank B1, and 34 and 35 indicate cam pulleys, respectively.

Moreover, the clearance of the second metal M2 bearing the second journal J2 of the crankshaft 8 is set smaller than the metal clearances of other parts.
In this embodiment, the first metal M1, the third metal M3,
3 for each metal clearance of the 4th metal M4
7 to 57 μm, the metal clearance of the second metal M2 is set to 37 to 50 μm, and the maximum value is changed, so that the clearance of the second metal M2 is set smaller than the other portions.

When setting the above-mentioned metal clearance, the outer diameter of each of the journals J1 to J4 of the crankshaft 8 is changed in advance without changing the wall thickness of each of the metals M1 to M4, so that the engine is assembled. The clearance of the second metal M2 is set smaller than the other parts without increasing the number of parts at that time.

As described above, the second cylinder CY is located on the side far from the accessory drive means 18 arranged at the end of the engine.
2 has a large inertia between the outside of the bank B2 where 2 exists and between the above-mentioned V banks (see the compressor 24 for the air conditioner and the resorum compressor 6). Since each auxiliary machine arranges the dynamic combined force F3 of the auxiliary machine drive belts 26 and 33 so as to be directed to the bank B2 on the side where the above-mentioned second cylinder CY2 exists, against seizure of metal. The load acting on the unfavorable No. 1 journal J1 is applied to the existing auxiliary machinery 6,
24 and the accessory drive belts 26 and 33 can be directed to the bank B2 on the second cylinder existing side as a different direction. As a result, the metal tapping noise can be reduced and the impact force can be mitigated to improve the engine reliability. There is an effect that can improve the sex.

That is, since the load acting on the first journal J1 which is disadvantageous to the seizure of the first metal M1 is directed in another direction, the metal tapping sound of the first metal M1 is reduced. In addition, the second journal J2 on the side where the load is directed has less swing of the crankshaft 8 than the first journal J1. There is an effect that the metal tapping sound of the number metal M2 can be reduced.

In addition, since the clearance of the second metal M2 bearing the second journal J2 of the crankshaft 8 is set to be smaller than the metal clearance of other parts, the above-mentioned dynamic synthetic force F3 is obtained. The second journal J2, which is apt to generate a metal tapping sound due to both the explosion pressure and
It is possible to reduce the stroke when an impact force is generated between the second metal M2 and the second metal M2. While preventing seizure of the second metal M2, the stroke is narrowed to reduce the impact force, and the engine This has the effect of improving durability and engine reliability.

Further, on the bank B2 side which is offset toward the rear end side of the crankshaft in the crankshaft direction, an auxiliary machine having a large inertia (the compressor 24 for the air conditioner 24
Since the auxiliary machine having the large inertia and the first auxiliary machine drive belt 26 direct the above-mentioned dynamic combined force F3 to the bank B2 on the side where the second cylinder CY2 exists. As a result, there is an effect that the load acting on the first journal J1 which is disadvantageous to seizure can be more favorably directed in the other direction.

In the correspondence between the configuration of the present invention and the above-described embodiment, the auxiliary machine of the present invention having a large inertia corresponds to the Rishorum compressor 6 and the compressor 24 for the air conditioner of the embodiment, and the auxiliary machine drive means. The bank on the side farther from the side where the second cylinder exists corresponds to the bank B2 on the other side, and the bank offset toward the crankshaft rear end direction side in the crankshaft direction is the bank B2 on the other side. The multi-cylinder engine corresponds to the V-type 6-cylinder engine, but the present invention is not limited to the configuration of the above-described embodiment.

For example, instead of the V-type engine exemplified in the embodiment, one cylinder row (bank) in which the first cylinder is present and the other cylinder example (bank) in which the second cylinder is present are offset horizontally. Of course, the above configuration may be applied to the opposed engine.

[Brief description of drawings]

FIG. 1 is a front view showing an accessory drive system for a multi-cylinder engine of the present invention.

FIG. 2 is a schematic perspective view of a cylinder block showing an offset state of each bank.

FIG. 3 is a vertical sectional view of a main part of a multi-cylinder engine.

[Explanation of symbols]

 6 ... Risholum compressor (auxiliary machine) 8 ... Crank shaft 18 ... Auxiliary machine driving means 24 ... Compressor (auxiliary machine) 26, 33 ... Belts for driving auxiliary machines B1, B2 ... Bank CY1 ... First cylinder CY2 ... Second cylinder F3 … Dynamic synthetic power J2… 2nd journal M2… 2nd metal

Claims (3)

[Claims] 1. An accessory drive device for a multi-cylinder engine in which an accessory drive means including a pulley for driving a plurality of accessories by a driving force of a crankshaft and an accessory drive belt is provided at an engine end. , Between one cylinder row in which the first cylinder is present and the other cylinder row in which the second cylinder is present, and on the side farther from the accessory drive means and on the side where the second cylinder is present. Auxiliary machines with large inertia are arranged outside the bank, and the dynamic synthetic force of the auxiliary machine driving belt is increased by the auxiliary machines with large inertia.
An accessory drive device for a multi-cylinder engine, which is arranged so as to be directed to the bank where the cylinders are present. 2. The accessory drive system for a multi-cylinder engine according to claim 1, wherein the clearance of the metal bearing the second journal of the crankshaft is set smaller than that of other parts. 3. The accessory drive device for a multi-cylinder engine according to claim 1, wherein an accessory having a large inertia is arranged on the bank side offset toward the rear end side of the crankshaft in the crankshaft direction.