JPH0718330B2 - Lubricator for engine with balancer shaft - Google Patents

Abstract

PURPOSE:To make an engine in a compact size by offsetting the bearing portion of a balance shaft having an auxiliary equipment attached thereto, in the longitudinal inward direction of an engine, opposite to the other side balance shaft and by providing a passage for lubricating chains at the portion of lubricating oil passage connected to both bearing portions. CONSTITUTION:Balance shafts 3, 4 driven by a crank shaft through sprockets 9, 10 and chains are provided at both side of a cylinder block 1. The bearing portion 3a of the balance shaft 3 having an auxiliary equipment 14 such as an oil pump arranged thereto is offset in the longitudinal inward direction of an engine in comparison the other bearing portion 4a of the balance shaft 4. Passages 26a, 26b for supplying oil to each of bearing portion 3a, 4a cross the longitudinal direction of an engine at right-angles so as to be connected thereto, by an offset amount, in the longitudinal direction of the engine and an oil jet nozzle 30 for lubricating the chains is connected to the tip end of the connecting portion.

Description

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a lubricating device for an engine, in which balancer shafts are arranged on both sides of a cylinder block, and an operating part of an auxiliary machine is provided on one of the balancer shafts. It is a thing.

(Prior Art) Conventionally, for example, as disclosed in Japanese Utility Model Publication No. 58-13166, in order to balance the inertial force of the engine, a drive mechanism composed of a chain or the like is provided on each side of the cylinder block. A balancer shaft that interlocks with the crankshaft is provided, and an actuating part of an auxiliary machine is provided at the end of one of the balancer shafts on the drive mechanism side. 2. Description of the Related Art There is known an engine in which the gear shaft of an oil pump is also used to simplify the structure.

In such an engine, an auxiliary machine such as an oil pump is attached to the outside of the bearing portion that supports one balancer shaft at one end side of the cylinder block, and this auxiliary machine projects outward from the cylinder block, and Since the drive mechanism is mounted on the outer side, the total length of the engine including the cylinder block, the auxiliary machine, and the drive mechanism becomes long.

Therefore, in order to reduce the overall length of the engine, it is desired to reduce the amount of protrusion of the above-mentioned auxiliary machine from the cylinder block. For that purpose, it is conceivable to indent the end of the cylinder block where the accessory is attached,
In this case, it is necessary to change the positional relationship between the one end side bearing portion with respect to one balancer shaft and the one end side bearing portion with respect to the other balancer shaft.

However, the above-mentioned bearing portion needs to be lubricated with oil, and as a lubrication system therefor, when the passages for supplying oil to both bearing portions are linearly formed in the direction orthogonal to the engine longitudinal direction, Since the passage and each bearing portion must correspond to each other, the arrangement of the bearing portion is restricted. Therefore, conventionally, it has been difficult to realize the above-described shortening of the engine while keeping the lubricating system in a relatively simple structure.

(Object of the Invention) In view of such circumstances, the present invention ensures lubricity of each bearing portion with respect to both balancer shafts, and makes it possible to process an oil passage relatively easily, and at the same time, to supplement the balance from the cylinder block. (EN) A lubrication device for an engine with a balancer shaft that can reduce the amount of protrusion of the machine and realize a reduction in the overall length of the engine.

(Structure of the Invention) The present invention provides a drive mechanism using a chain in which balancer shafts are arranged on both sides of a cylinder block, and a chain for interlocking each balancer shaft with a crankshaft is provided outside one end of the cylinder block. In a balancer shaft engine equipped with a balancer shaft equipped with an actuating part of an auxiliary machine at the end of one balancer shaft on the drive mechanism side, the other bearing part for the balancer shaft at the end of the cylinder block on the drive mechanism side is Is provided inwardly in the longitudinal direction of the engine with respect to the bearing portion with respect to the balancer shaft, and in the passage for supplying oil to each of the above-mentioned bearing portions, a passage portion leading to one bearing portion and a passage portion leading to the other bearing portion are provided. Is orthogonal to the longitudinal direction of the engine and is displaced in the longitudinal direction of the engine by the above offset amount. A chain lubrication road is provided which is formed and is orthogonal to both of the passages and has a tip opening toward the chain.

That is, the bearing portion is arranged so that the amount of protrusion from the cylinder block of the auxiliary machine located outside one of the bearing portions is small, and the above-mentioned both passage portions are formed so as to correspond to the arrangement of each bearing portion. Moreover, the passage that connects the two passage portions is used as a road for chain lubrication.

(Embodiment) FIGS. 1 to 3 show a specific example of an engine with a balancer shaft equipped with a lubricating device of the present invention. In these figures, 1 is a cylinder block, and a lower portion thereof has a width direction. The crankshaft 2 is attached to the central portion, and the balancer shafts 3 and 4 are attached to both side portions. Each of these balancer shafts 3 and 4 has journal portions 3a to 3c and 4a to 4c at a plurality of positions, and eccentric portions 3d and 4c.
equipped with d, each of the above journal parts 3a-3c, 4a-4c
Are bearing parts 5a to 5c, 6a formed on the cylinder block 1.
6c are supported by bushes 7 respectively.
A transmission mechanism that interlocks the balancer shafts 3 and 4 with the crankshaft 2 is provided outside one end (front end) of the cylinder block 1. As shown in FIG. 3, this transmission mechanism includes a sprocket 8 attached to the crankshaft 2, a sprocket 9 attached to one of the balancer shafts 3 (right side in the figure), and the other (left side of the figure) balancer. Gear 10 mounted on shaft 4
And a sprocket 12 mounted on a shaft 11 having a gear that meshes with the gear 10, and a chain 13 hung on each sprocket 8, 9, 11. The balancer shafts 3 and 4 are interlocked with the crankshaft 2 by this transmission mechanism so that the balancer shafts 3 and 4 rotate in directions opposite to each other at a rotation speed twice the rotation speed of the crankshaft 2.

In addition, an operating portion of an auxiliary machine is provided at the end of one balancer shaft 3 on the drive mechanism side. In this embodiment, an oil pump 14 of a gear pump chamber is provided as an auxiliary machine, and a drive gear of this oil pump 14 is provided. The balancer shaft 3 doubles as a gear shaft of the oil pump 14 by attaching 15 to the portion between the journal portion 3a and the sprocket 9 on one end side of the balancer shaft 3.

On the front end side of the cylinder block 1 equipped with the drive mechanism and the oil pump 14, the bearing portion 5a that supports the journal portion 3a of the one balancer shaft 3 is a bearing that supports the journal portion 4a of the other balancer shaft 4. It is offset more inward in the longitudinal direction of the engine than the portion 6a, and a concave portion 1a recessed by the offset is formed on the front surface of the cylinder block 1 in this portion. And
By mounting the oil pump 14 at the location where the recess 1a is formed, the amount of protrusion of the oil pump 14 from the front end of the cylinder block 1 is reduced by the offset.

As shown in FIGS. 4 and 6, the oil pump 14 includes a drive gear 15, a driven gear 16 meshing with the drive gear 15, and a pump body 17 for accommodating both gears 15, 16.
And a pump cover 18 that covers the front side of this pump body 17.
The pump body 17 is provided with an oil suction port 19 and an oil discharge port 20, and a regulator valve 21 for adjusting the discharge pressure. And
The pump body 17 and the pump cover 18 are mounted in the recess 1a on the front surface of the cylinder block 1, and one end of the balancer shaft 3 projects into the pump body 17 and the drive gear 15 is mounted therein. Further, the sprocket 9 is attached to the shaft 22 which is connected to the drive gear 15 and projects outward from the pump cover 18. In addition, one side of the sprocket 9 is a pin hinge and the other side is the cylinder block 1 on the side.
A chain guide 23, which is mounted so that its position can be adjusted, is arranged, and in order to lay out the chain guide 23 and the oil pump 14 in a compact manner, bolts for fastening the pump body 17 and the pump cover 18 on the upper side of the oil pump 14 are arranged. A shaft portion 25 that pivotally supports a mounting piece 23a on one end side of the chain guide 23 is integrally provided on the 24 (see FIGS. 4 and 5).

As a lubrication system for lubricating the bearing portions of the balancer shafts 3 and 4, the balancer shaft 3,
An oil supply passage 26 for supplying oil for lubrication is arranged in each of the bearing portions 5a to 5c and 6a to 6c for the four. The oil supply passage 26 is connected to an oil passage 28 extending from the main oil gallery 27 toward the crankshaft bearing portion, and the main oil gallery 27 is connected via the oil passage 28.
Is in communication with.

Particularly, the oil supply passage 26 for supplying oil to the bearing portions 5a, 6a on the front end side of the cylinder block 1 is provided from a predetermined position of the cylinder block 1 as shown in FIG. 1 and FIG. It has a passage portion 26a reaching the bearing portion 5a of one balancer shaft 3 and a passage portion 26b reaching the bearing portion 6a of the other balancer shaft 4, and both passage portions 26a, 26b are orthogonal to the engine longitudinal direction, Further, they are formed at positions displaced in the engine longitudinal direction by the offset of both bearings 5a, 6a. Further, the diameter of the passage portion 26a is set smaller than the diameter of the passage portion 26b. Then, the both bearing portions 5a, 6a,
At the predetermined location of the cylinder block 1, both bearing parts
A chain lubrication passage 29, which extends orthogonally to 5a and 6a and extends toward the front end side of the cylinder block 1, is connected to the chain lubrication passage 29. An oil jet nozzle 30 protruding forward of the cylinder block 1 is attached to the chain lubrication passage 29. ing. The tip of the oil jet nozzle 30 opens toward the chain 13 of the drive mechanism. In this embodiment, the passage portion 26a
Since the diameter of is smaller than the diameter of the passage portion 26b, the oil pressure to the oil jet nozzle 30 can be secured. Further, while the oil jet nozzle 30 is arranged in the vicinity of the bolt 24 that is commonly used for fastening the pump body 17 and the pump cover 18 and mounting the chain guide 23,
The opening direction of the oil jet nozzle 30 is set so that the oil is sprayed in a range (a range shown by a thin line A in FIG. 5) extending over the chain guide 23 mounting portion by the shaft portion 25 of the bolt 24 and the chain 13. There is.

With respect to the bearing portion 5a on the one balancer shaft 3 side, the bearing portion is formed on the outer side of the cylinder block 1 on the side opposite to the passage portion 26a by utilizing the perforated portion when processing the passage portion 26a. An oil outlet passage 31 for allowing the oil that has lubricated 5a to flow out is formed, and the thrust inside the oil pump 14 extends from this oil outlet passage 31 to the front end of the cylinder block 1 and the pump body 17 and pump cover 18 of the oil pump 14. An oil passage 33 for sending oil is formed in a sliding portion such as the plate 32 and a gear shaft.

According to the lubricating device having the above structure, the oil sent from the main oil gallery 27 to the oil supply passage 26 is provided on one end side of the cylinder block 1 in which the drive mechanism including the chain 13 and the oil pump 14 are arranged. Passes through the passage portions 26a and 26b of the oil supply passage 26 and is supplied to the bearing portions 5a and 6a for the balancer shafts 3 and 4 on both sides. In this case, as described above, in order to reduce the amount of protrusion of the oil pump 14 from the cylinder block 1, the bearing portion 5a for the one balancer shaft 3 is offset more inward than the bearing portion 6a for the other balancer shaft 4. However, with respect to such arrangement of the bearing portions 5a and 6a, the oil supply passage 26 is formed by being shifted by the offset, and both the passage portions 26a and 26b are connected by the chain lubrication passage 29. Therefore, the oil is effectively collected in each bearing 5a, 6a.
Is supplied to. Further, oil is also sent from the oil supply passage 26 to the chain lubrication passage 29, and is also used for lubrication of the chain 13. In this case, in this embodiment, oil is jetted from the oil jet nozzle 30 over the pin hinge portion on one end side of the chain guide 23 and the chain 13, whereby the lubricity of the pin hinge portion is also improved, and the fineness of this portion is improved. Vibration is prevented.

In addition, the passage portions 26a, 26b and the chain lubricating oil passage 2
9 is easily formed by the following processing. That is, the passage portions 26a, 26b are bored from both side surfaces of the cylinder block 1 to the predetermined locations inside the cylinder block 1 through the bearing portions 5a, 6a, respectively, and the bored portion open end of the side surface of the cylinder block 1 is formed. Has a blind plug 34
Is installed. Further, since the two passage portions 26a, 26b are displaced from each other, it is necessary to form a passage for communicating these passages, but the present invention uses this passage as the chain lubrication passage 29, and this passage is used as a cylinder block. The oil jet nozzle 30 is attached to the perforation 1 from the front side. Therefore, both the above-mentioned passage parts 26a, 26b
The structure is simplified and the processing is simplified as compared with the case where the passage communicating with and the passage for supplying oil to the chain 13 are formed separately.

(Effects of the Invention) As described above, according to the present invention, the bearing portion for one balancer shaft provided with the operating portion of the auxiliary machine at the end portion on the drive mechanism side of the cylinder block is more important than the bearing portion for the other balancer shaft. Since it is offset inward in the longitudinal direction, it is possible to reduce the protrusion amount of the auxiliary machine from the cylinder block and shorten the overall length of the engine. And, in the passage for supplying oil to both the bearing portions, two passage portions that are offset by the offset are provided,
Since both of these passages are communicated with each other by the chain lubrication passage, it is possible to reduce the total length of the engine as described above without interfering with the lubrication of each portion with a relatively simple passage configuration. Is.

[Brief description of drawings]

1 is a horizontal sectional view showing an embodiment of the present invention, FIG. 2 is a sectional view taken along line II-II in FIG. 1, FIG. 3 is a side view showing a balancer shaft drive mechanism, and FIG. FIG. 5 is an enlarged horizontal cross-sectional view of a main part, FIG. 5 is an enlarged side view of the vicinity of a chain attachment portion in a drive mechanism, and FIG. 1 ... Cylinder block, 3, 4 ... Balancer shaft, 3a-3
c, 4a to 4c ... journal part, 5a to 5c, 6a to 6c ... bearing part, 14
... oil pump (auxiliary equipment), 15 ... drive gear (operating part of auxiliary equipment), 26 ... oil supply passage, 26a, 26b ... passage portion, 29 ...
Chain lubrication passage.

Claims (1)

[Claims] 1. A balancer shaft is provided on each side of a cylinder block, and a drive mechanism using a chain for interlocking each balancer shaft with a crankshaft is provided outside one end of the cylinder block. In an engine with a balancer shaft in which an actuating part of an auxiliary machine is provided at the drive mechanism side end of one balancer shaft, the bearing portion for the one balancer shaft at the drive mechanism side end of the cylinder block is Offsets are provided inward in the longitudinal direction of the engine with respect to the bearing portions, and a passage portion that supplies oil to each of the bearing portions includes a passage portion that reaches one bearing portion and a passage portion that reaches the other bearing portion. If it is formed orthogonal to the direction and shifted in the engine longitudinal direction by the above offset, To, the perpendicular to both passages, and tip lubricating device of the balancer engine with shaft, characterized in that a chain lubricant passage which opens toward the chain.