JP2018123741A - Lubrication device for cam shaft of internal combustion engine - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a lubrication device capable of appropriately lubricating a cam shaft for opening and closing an intake valve and a cam shaft for opening and closing an exhaust valve, different from each other in height, in a slant type internal combustion engine in which a cylinder bore axis is inclined to a vertical line.SOLUTION: An upper injection pipe portion 16 and a lower injection pipe portion 17 are connected to a relay pipe portion 18 through joints 20, 21. Throttle members 28a-28c, 29a-29c are incorporated in the joints 20, 21. By adjusting cross-sectional areas of holes of the first throttle members 28a, 29a, distribution amounts to the upper injection pipe portion 16 and the lower injection pipe portion 17 can be equalized. By adjusting the second and third throttle members 28b, 29b, 28c, 29c, an amount of oil can be equalized over the whole length of the upper injection pipe portion 16 and the lower injection pipe portion 17.SELECTED DRAWING: Figure 7

Description

  The present invention relates to an apparatus for lubricating an intake valve opening / closing cam shaft and an exhaust valve opening / closing cam shaft in a slant type internal combustion engine. In the present invention, the lubrication of the camshaft widely includes the lubrication of the valve operating portion. Therefore, in addition to lubrication of the contact point between the cam and the intake / exhaust valve and lubrication of the contact point between the cam and the tappet, rotation lubrication of the cam shaft itself and lubrication of the sliding portion of a member such as a tappet Also included.

  In an internal combustion engine, as one aspect of a camshaft lubrication means, a pipe lubrication device is disposed in a valve operating chamber, and oil is injected from the lubrication device onto a camshaft. Since there are two camshafts for opening and closing the intake valve and for opening and closing the exhaust valve, the lubricating device includes a pipe portion extending along the camshaft for opening and closing the intake valve, and a tube portion extending along the camshaft for opening and closing the exhaust valve. There are many oil ejection holes in both pipe portions.

  Oil is supplied to the lubrication device from one oil supply port (oil gallery) provided in the cylinder head, and accordingly, the pipe portion extending along the intake valve opening / closing cam shaft and the intake valve opening / closing cam shaft. It is necessary to connect the pipe portion that extends to the oil supply port by connecting the pipe portion to the oil supply port.

  As a specific structural example of a lubricating device, Patent Document 1 discloses a relay pipe that includes one end of a pipe portion extending along an intake valve opening / closing cam shaft and one end of a pipe portion extending along an exhaust valve opening / closing cam shaft. An example in which the lubricating device is formed in a U-shape as a whole by connecting parts is disclosed. And when connecting a relay pipe part to a cylinder head with a joint, the branch passage provided in the joint has the same cross-sectional area, so that the pipe part extending along the intake valve opening / closing cam shaft and the exhaust valve opening / closing cam shaft It is set so that the same amount of oil flows through the pipe portion extending along the line.

JP 2009-221985

  In the internal combustion engine, there are a vertical type in which the cylinder bore is in a substantially vertical posture and a slant type in which the cylinder bore is inclined with respect to a substantially vertical line. Spread evenly throughout.

  However, in a slant type internal combustion engine, the intake valve opening / closing cam shaft and the exhaust valve opening / closing cam shaft are different in height, so that the lubricating device also has a height of a portion extending along the intake valve opening / closing cam shaft. The height of the portion extending along the exhaust valve opening / closing camshaft is different, and therefore, when the configuration of Patent Document 1 is applied as it is, to the portion of the lubricating device having a higher height due to the influence of gravity. This causes a problem that the amount of oil supplied becomes too small and the amount of oil supplied to the low height portion becomes excessive, resulting in uneven lubrication of the two camshafts.

  Further, the high-side camshaft in which the supply of oil is excessively hindered smooth movement, and may cause problems such as seizure in severe cases. Therefore, when Patent Document 1 is applied to the slant type, the amount of oil supplied to the pipe portion having a high height in the lubricating device must be set to an appropriate amount, but then the capacity of the oil pump must be increased. Therefore, there is a risk that the fuel consumption will be reduced.

  The present invention has been made to improve the current situation.

The present invention relates to a lubrication device that ejects oil toward camshafts that are arranged in parallel and horizontally with different heights.
Upper injection pipe for lubricating a camshaft with a high height, a lower injection pipe for lubricating a camshaft with a low height, and a relay pipe for supplying oil to the upper and lower pipes And
Furthermore, a flow rate adjusting means is provided for making the oil injection amount from the upper injection tube portion substantially equal to the oil injection amount from the lower injection tube portion.

  The present invention can be developed in various ways. For example, in Patent Document 1, the lubricating device is formed in a U-shape as a whole, whereas the relay pipe portion is connected between one end and the other end of the upper injection pipe portion and the lower injection pipe portion. By doing so, the lubricating device can be formed in an H shape as a whole. In the case of this aspect, the injection pipe part and the relay pipe part are connected in a T shape, and the oil branches from the relay pipe part to the left and right and flows to the injection pipe part, but the injection pipe part and the relay pipe part Can be connected by a T-shaped joint having three pipes.

  Then, each of the three pipes constituting the T-shaped joint is provided with a throttle for adjusting the flow rate, and the cross-sectional area of the hole in each throttle is adjusted by the upper injection pipe and the lower injection pipe. By doing so, oil can be uniformly supplied to each part of the upper injection pipe part and the lower injection pipe part.

  As another development example, a downward bent portion is formed in the upper injection pipe portion and the lower injection pipe portion where there is no oil injection hole, and oil remains in the bent portion after the engine stops. Can be set to be

  In the present invention, even if the internal combustion engine is a slant type, oil is evenly supplied to the entire upper injection pipe portion and lower injection pipe portion of the lubrication device by providing the flow rate adjusting means in the lubrication device. it can. Therefore, the intake valve opening / closing cam shaft and the exhaust valve opening / closing cam shaft can be lubricated without excess or deficiency. As a result, the internal combustion engine can be operated smoothly and wear can be suppressed to ensure high durability. Further, since it is not necessary to increase the capacity of the oil pump, it is possible to prevent a decrease in fuel consumption.

  Although various structures can be adopted for the flow rate adjusting means, if a cylindrical throttle member is arranged in the pipe constituting the joint as in the embodiment, the oil directed to each part by attaching a throttle member having a different cross-sectional area Since the amount can be adjusted, in various internal combustion engines having different slant angles, only one throttle member is required and only one type of lubricating device is sufficient. Therefore, when various internal combustion engines having different slant angles are prepared, or when a slant type and a vertical type internal combustion engine are prepared, the members can be made common and the overall cost can be suppressed.

  In addition, if oil comes off from the inside of the lubrication system after the engine stops, there will be a time lag between the start of rotation of the camshaft and the injection of oil at the next start, which may result in insufficient start-up lubrication. However, if a downward bend is formed in the upper injection pipe and the lower injection pipe of the lubrication device, as in the case of a lubrication device, the oil will accumulate in the bend after the engine stops, causing the next start-up. Since oil is sometimes injected quickly onto the camshaft, there is an advantage that it can be properly lubricated from the initial stage of starting.

  Now, when the engine is stopped, the oil filled in the oil gallery falls out to the oil pan or the like due to gravity, and therefore a negative pressure is generated in the oil gallery. For this reason, the oil inside the lubrication device provided in the valve operating chamber is drawn, but when the downward bent portion is formed as in the embodiment, the oil accumulated in the downward bent portion may return toward the oil gallery. , Blocked by the throttle. For this reason, the function of accumulating oil in the downward bent portion after the engine is stopped can be ensured, and the lubrication at the next start can be ensured.

It is the partial front view which looked at the internal combustion engine from the crankshaft direction. FIG. 2 is a view taken along the line II-II in FIG. 1 with the head cover omitted (a top view viewed from the cylinder bore line direction). It is the top view which looked at the lubricating device from the cylinder bore axial direction. (A) is a perspective view of the lubricating device, (B) is a view taken along IVB-IVB in FIG. 3, and (C) is a view taken along IVC-IVC in FIG. It is a partial bottom view of a lubricating device. FIG. 6 is a sectional view taken along line VI-VI in FIG. 3. It is the pipe line figure which displayed the connection part in the cross section.

(1). Outline Next, an embodiment of the present invention will be described with reference to the drawings. First, an outline will be described. As shown in FIG. 1, the internal combustion engine includes a cylinder block 1, a cylinder head 2, and a head cover 3, and a posture in which an axis 5 of a cylinder bore 4 formed in the cylinder block 1 is greatly inclined with respect to a vertical line 6. Is arranged. That is, the internal combustion engine is a slant type. In the present embodiment, the cylinder bore axis 5 is greatly inclined so as to be closer to the horizontal plane 7 than the vertical line 6.

  In the present embodiment, the cylinder head 2 is arranged so that the intake side surface 2a faces upward and the exhaust side surface 2b faces downward. In the present embodiment, for convenience, the state viewed from the direction of the cylinder bore axis 5 is referred to as a top view and a bottom view, and the top surface of the cylinder head 2 opposite to the cylinder block 1 is the top surface. I'm calling. The crank axis direction is called the front-rear direction, and the part where the chain cover (furoton cover) is arranged is in front.

  A recess 8 is formed on the upper surface of the cylinder head 2. As shown in FIG. 2, the intake valve opening / closing cam shaft 9 and the exhaust valve opening / closing cam shaft 10 have different heights in the recess 8. They are arranged in a parallel and horizontal position. Since the intake side surface 2a is high, the intake valve opening / closing camshaft 9 is at a high position and the exhaust valve opening / closing camshaft 10 is at a low position. The cam shafts 9 and 10 are rotatably held by cam caps, but the cam caps are not shown.

  The internal combustion engine of the present embodiment has four cylinders, and first to fourth four pairs of cams 11a to 11d and 12a to 12d are formed on the camshafts 9 and 10 in order from the trouble (cams). Are sometimes collectively referred to by reference numerals 11 and 12.). In the present embodiment, the valve (not shown) is opened and closed by the camshafts 9 and 10 via the tappet, but the illustration of the valve and the tappet is omitted. Needless to say, the valve shaft can be directly opened and closed by the camshafts 9 and 10 without using a tappet.

  As shown in FIG. 2, the cylinder head 2 is formed with a cylinder portion 13 into which a spark plug and an ignition device are inserted concentrically with the cylinder bore axis 5. The head cover 3 is fixed so as to overlap the upper surface of the outer peripheral portion of the cylinder head 2.

(2) Lubricating device The cylinder head 2 is provided with a lubricating device 15 for lubricating the sliding surfaces of the cams 11 and 12 of the cam shafts 9 and 10 and the tappet. The lubrication device 15 includes an upper injection pipe portion 16 for lubricating the intake valve opening / closing camshaft 9, a lower injection pipe portion 17 for lubricating the exhaust valve opening / closing camshaft 10, and upper and lower injection pipes. And a relay pipe section 18 connecting the pipe sections 16 and 17.

  The upper injection pipe section 16 and the lower injection pipe section 17 are inevitably long in the front-rear direction as the cam shafts 9 and 10, and the relay pipe section 18 is orthogonal to the cam shafts 9 and 10. It has a long shape in the left-right direction. Each of the pipe portions 16, 17, and 18 can use either a metal pipe or a resin pipe.

  A first joint 19 into which oil flows from an oil passage (gallery) 22 a formed in the cylinder head 2 is connected to a lower portion of the relay pipe portion 18 that is close to the exhaust valve opening / closing cam shaft 10. On the other hand, the relay pipe part 18 and the upper injection pipe part 16 are connected by a T-shaped second joint 20, and the relay pipe part 18 and the lower injection pipe part 17 are connected by a third joint 21. .

  4-6, the 1st coupling 19 is formed in the block shape, the flange 24 fixed to the boss | hub part 22 formed in the cylinder head 2 with the volt | bolt (screw) 23, and the cylinder head 2 of FIG. Three-way branch holes 25, 26, 27 communicating with an oil supply port (oil gallery) 22a formed in the boss part 22 are formed, and the relay pipe part 18 is inserted into the two branch holes 26, 27 by insertion. It is connected. A sealing material 22 b is interposed between the first joint 19 and the boss portion 22.

  The branch holes 26 and 27 that connect the relay pipe portion 18 are substantially orthogonal in a top view, and the portion of the relay pipe portion 18 that faces the lower injection pipe portion 17 changes from a front-back direction posture to a downward posture. As shown, it has a substantially L-shaped form. On the other hand, the 2nd joint 20 and the 3rd joint 21 are located in the part between a pair of 2nd cams 11b and 12b, respectively. Accordingly, the embodiment is roughly in the form of a lateral H-shape.

  As shown in FIG. 7, the second and third joints 20 and 21 are three-way systems having three pipes, and the pipe parts 16, 17, and 18 are inserted into the respective pipes. The upper injection pipe section 16 is fitted by fitting cylindrical throttle members 28a to 28c and 29a to 29c, respectively, and adjusting the cross-sectional areas of the holes (flow paths) in the throttle members 28a to 28c and 29a to 29c. And the lower injection pipe portion 17 are set so that the flow rate of oil is uniform without excess or deficiency (reference numerals 28 and 29 are used to collectively refer to a group of throttle members).

  That is, first, in the second joint 20 and the third joint 21, by correcting the influence of gravity and adjusting the cross-sectional areas of the first throttle members 28a and 29a connected to the relay pipe portion 18, It is set so that the same amount of oil flows through the upper injection pipe section 16 and the lower injection pipe section 17. Accordingly, the cross-sectional area of the hole of the first throttle member 28 a in the second joint 20 is larger than the cross-sectional area of the hole of the first throttle member 29 a in the third joint 21.

  Next, since the lengths of the upper and lower injection pipe parts 16 and 17 are different on the front and rear sides sandwiching the joints 20 and 21, the second throttle member 28b at the part to which the pipe parts 16 and 17 are connected. 29b and the third throttle members 28c and 29c are adjusted so that oil flows according to their lengths on both the front and rear sides of the joints 20 and 21 by adjusting the cross-sectional areas of the holes.

  Since the joints 20 and 21 are arranged at the locations of the second cams 11b and 12b, the long portions of the cross-sectional areas of the second throttle members 28b and 29b arranged at the locations where the short portions are connected are connected. It is smaller than the cross-sectional area of the third throttle members 28c and 29c arranged at the locations.

  Therefore, when the throttle members 28 and 29 of the joints 20 and 21 are put together, the first throttle members 28a and 29a have the first flow rate that equalizes the distribution amount to the upper injection pipe portion 16 and the lower injection pipe portion 17. The second and third throttle portions 28b, 29b, 28c, and 29c constituting the adjusting means are second flow rate adjustments for equalizing the ejection amount over the entire length in each of the injection pipe portions 16 and 17. Means.

  A downward bent portion 31 is formed in each of the upper injection tube portion 16 and the lower injection tube portion 17. Precisely, between the first cams 11a, 12a and the second cams 11b, 12b, between the second cams 11b, 12b and the third cams 11c, 12c, the third cams 11c, 12c and the fourth cam 11d, A downward bent portion 31 is formed between 12d and 12d. As shown by taking the lower injection pipe portion 17 in FIG. 5, the injection pipe portions 16 and 17 have a large number of oil injection holes 32, but the oil injection holes 32 are formed in the downward bent portion 31. It has not been.

  An intermediate bracket 33 made of a plate material is fixed to the lower bent portion 31 in both the upper and lower injection pipe portions 16 and 17, and the intermediate bracket 33 is provided on the cylinder head 2 by bolts (not shown). (However, the intermediate bracket 33 is not provided in the lower bent portion of the lower injection pipe portion 17 at the front bent portion.) A stud bolt may be attached to the cylinder head 2 and screwed into the cylinder head 2 to fix the intermediate bracket 33 to the cylinder head 2 with a nut. Since the intermediate bracket 33 is in a state surrounded by the downward bent portion 31, the intermediate bracket 33 can be prevented from protruding and the lubricating device 15 can be made compact.

  An end bracket 34 is provided at the other end of the injection pipes 16 and 17 located outside the fourth cams 11d and 12d. Further, the upper and lower injection pipe portions 16 and 17 are connected to each other by reinforcing stays 35 and 36 at two front and rear positions, and the stays 35 and 36 are fixed to the cylinder head 2 with bolts. In the example of the figure, one reinforcing stay 35 is disposed at the location of the first cams 11a, 12a, and the other reinforcing stay 36 is located at the location between the third cams 11c, 12c and the fourth cams 11d, 12d. However, the location and number of reinforcing stays can be arbitrarily set in consideration of interference with other members.

  The first joint 19 is partially surrounded from below by a downward bending portion 31 on the near side of the lower injection pipe portion 17. For this reason, the 1st coupling 19 and the lower side injection pipe part 17 are in the state put together, and are made compact.

  The lower end of the other reinforcing stay 36 is integrated with an intermediate bracket 33 fixed to the lower injection pipe portion 17. For this reason, a member can be shared and compactized. Note that both ends of the injection pipe portions 16 and 17 are blocked or crushed by plugs or the like.

(3) Summary As described above, in the present embodiment, the upper injection pipe section 16 and the lower injection pipe section 17 are provided by the throttle members 28 and 29 provided in the second and third joints 20 and 21. The oil is evenly distributed throughout. For this reason, the camshafts 9 and 10 can be lubricated without excess or deficiency without increasing the capacity of the oil pump.

  Since the throttle members 28 and 29 can be exchanged, when a plurality of types of internal combustion engines having different slant angles are prepared, the cross-sectional area may be adjusted according to the slant angle. Therefore, most of the lubricating device 15 can be shared. When applied to a vertical internal combustion engine, the cross-sectional areas of the holes of the first throttle members 28a and 29a in the second and third joints 20 and 21 may be set to be the same. Therefore, the member can be shared between the slant type and the vertical type.

  Since the oil is accumulated in the downward bent portion 31 after the engine is stopped, when the oil pump is driven at the next start, the oil accumulated in the downward bent portion 31 is pushed by the air and is applied to the camshafts 9 and 10. It spouts towards. For this reason, the camshafts 9 and 10 can be appropriately lubricated from the beginning of the start.

  Since the throttle members 28a to 29c are resistant to the oil flow, as described in the column of the effect of the invention, the return of oil when the engine is stopped can be prevented by the throttle members 28a to 29c. In the embodiment, the return prevention of the oil accumulated in the downward bent portion 31 is first blocked by the second and third throttle members 28c, 28c, 29b, 29c, and further blocked by the second throttle members 28a, 29a. Therefore, even if a negative pressure is generated in the oil gallery due to oil dropping off when the engine is stopped, the return of oil can be firmly prevented. Therefore, it is possible to further ensure the lubrication at the next start by keeping the oil in the downward bent portion 31.

  In the present embodiment, the flange 24 of the first joint 19 is surrounded by the downward bent portion 31 of the lower injection pipe portion 17, and the bolt insertion hole of the flange 24 and the bolt insertion hole of the bracket 33 are straight in the front-rear direction. Are lined up. For this reason, in forming the mounting boss portion on the cylinder head 2, it is easy to avoid interference with other members.

  If the reinforcing stays 35 and 36 are provided as in the present embodiment, the stability of the lubricating device 15 can be improved. Further, when the oil flows through the pipe, the pressure loss increases as the distance becomes longer. However, when the lubricating device 15 is formed in an H shape as in the present embodiment, the pressure loss is suppressed as much as possible, and the injection pipe portion The oil can be evenly distributed over the entire length.

  In the above embodiment, the throttle member is used as the flow rate adjusting means, but the flow rate adjusting means having other structures can also be adopted. For example, taking the relay pipe portion 18 as an example, the upper injection pipe portion is formed by changing the diameters of the upper and lower sides sandwiching the first joint 19 so that the upper side has a large diameter and the lower side has a small diameter. It is possible to equalize the amount of oil flowing through 16 and the lower injection pipe portion 17.

  As a means for equalizing the flow rates of the upper injection pipe section 16 and the lower injection pipe section 17, a throttle member may be provided in the first joint 19. As the flow rate adjusting means, a variable type such as a needle type can also be adopted. When adjusting the flow rate by reducing the inner diameter of the tube, it is also possible to adjust the cross-sectional area of the flow path by crushing the tube into a flat shape or the like. It is also possible to form the throttle part integrally with the joint.

  The present invention can actually be embodied in an internal combustion engine. Therefore, it can be used industrially.

2 Cylinder Head 4 Cylinder Bore 5 Cylinder Bore Axis 6 Vertical Line 9 Intake Valve Open / Close Cam Shaft 10 Exhaust Valve Open / Close Cam Shaft 11a-12d Cam 15 Lubricator 16 Upper Injection Pipe 17 Lower Injection Pipe 18 Relay Pipe DESCRIPTION OF SYMBOLS 19 1st joint 20 2nd joint 21 3rd joint 25-27 Branch hole 28a-29c Restriction member 31 Downward bending part 32 Oil ejection hole 33, 34 Bracket 35, 36 Reinforcement stay

Claims (1)

A lubricating device that ejects oil toward camshafts arranged in parallel and horizontally with different heights,
Upper injection pipe for lubricating a camshaft with a high height, a lower injection pipe for lubricating a camshaft with a low height, and a relay pipe for supplying oil to the upper and lower pipes And
Furthermore, there is provided a flow rate adjusting means for making the oil injection amount from the upper injection pipe portion substantially equal to the oil injection amount from the lower injection pipe portion.
A lubrication device for a camshaft of an internal combustion engine.

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