JP6550961B2 - Hydraulic pressure adjustment mechanism of internal combustion engine - Google Patents

Description

  The present invention relates to a hydraulic pressure adjustment mechanism of an internal combustion engine.

  In an internal combustion engine such as an engine, the amount of oil discharged from the oil pump is increased according to the rotational speed of a crankshaft. Although the oil pressure flowing through the oil gallery (oil supply path) increases with the increase of the oil discharge amount, the increase of the oil pressure acts as a resistance and increases the friction loss in the oil gallery. In order to maintain the oil pressure at or below the upper limit range, the oil gallery is provided with a pressure control valve that is opened when the oil pressure reaches a predetermined upper limit threshold to discharge the oil. However, since this pressure control valve performs open / close control depending on whether the oil pressure has reached the upper threshold value, it may be higher than the oil pressure suitable for the rotational speed of the crankshaft.

  In order to adjust the oil pressure supplied from the oil pump according to the number of revolutions of the crankshaft, for example, in Patent Document 1, the oil supply flow path is branched, and the main flow path upstream of the branch point and the branch point An adjustment mechanism is disclosed that arranges a spool and a valve in a downstream branch flow path, and adjusts the oil pressure to be suitable for each of a low rotation region, a middle rotation region, and a high rotation region.

JP, 2014-15869, A

  In the adjustment mechanism described above, the oil pressure is adjusted in three steps of the low rotation region, the middle rotation region and the high rotation region, but it is desired to adjust to the oil pressure suitable for the rotation number of the crankshaft.

  The disclosed hydraulic adjustment mechanism is intended to adjust to an oil pressure suitable for the rotational speed of the crankshaft.

  The disclosed hydraulic pressure adjustment mechanism is disposed in the oil supply passage, and an oil pump that raises the discharge amount of the oil according to the increase in the rotational speed of the crankshaft, and the oil flow more than the arrangement position of the oil pump in the oil supply passage. And an oil discharge unit which is communicated with the downstream side of the direction and which transmits the rotation of the crankshaft and increases the amount of oil discharge according to the increase in the rotation speed of the crankshaft.

  According to the disclosed hydraulic pressure adjustment mechanism, it is possible to adjust to an oil pressure suitable for the rotational speed of the crankshaft.

FIG. 2 is a cross-sectional view schematically illustrating the inside of an engine. (A) is a perspective view schematically explaining the appearance of a rotating member. (B) is a figure which illustrates the head of a rotation member typically. (A) is a fragmentary sectional view which illustrates the attachment state of a rotation member typically. (B) is a figure which illustrates typically the head of the rotation member in an attachment state. FIG. 4A is a partial cross-sectional view that schematically illustrates a rotating state of a rotating member. (B) is a figure which illustrates typically the head of the rotation member in a rotation state. 4 is a graph schematically illustrating a relationship between a crankshaft rotation speed and engine oil pressure.

  Hereinafter, a hydraulic adjustment mechanism according to an embodiment of the present invention will be described with reference to the accompanying drawings.

  A diesel engine 1 (an example of an internal combustion engine, hereinafter simply referred to as an engine 1) shown in FIG. 1 includes a crankshaft 2, a rocker arm shaft 3, a camshaft 4 and an oil circulation mechanism 5.

  The crankshaft 2 is a rotating shaft that converts the reciprocating motion of the piston PS into a rotational force, and a crank throw 13 having a crank pin 11 and a crank arm 12 is provided corresponding to the set of the piston PS and the connecting rod CR. . A large end of the connecting rod CR is attached to the crankpin 11 in a rotatable state. An oil supply passage 15 is provided in the crankshaft 2 from the crank journal 14 through the crank arm 12 to the crank pin 11. Oil is supplied to the oil supply passage 15 from a sub gallery 36 provided in the oil circulation mechanism 5.

  The rocker arm shaft 3 is a member that swingably supports the rocker arm 21. In the present embodiment, an oil flow path 22 is provided inside. Oil is supplied to the oil flow path 22 from the oil circulation mechanism 5. The oil supplied to the oil passage 22 is supplied to the cam shaft 4. The cam shaft 4 is a member provided with a cam 23 for swinging the rocker arm 21, and rotates according to the rotation of the crankshaft 2.

  The oil circulating mechanism 5 supplies the oil stored in the oil reservoir POC to the crankshaft 2 and the rocker arm shaft 3 and includes an oil strainer 31, an oil pump 32, an oil filter 33, and a bypass valve 34. , A refueling pipe 35, a sub gallery 36, and an oil discharger 37. A series of flow paths from the oil strainer 31 to the crankshaft 2 (crank journal 14) and the rocker arm shaft 3 (oil flow path 22) is an oil supply path provided in the oil circulation mechanism 5.

  The oil strainer 31 is disposed on the most upstream side in the oil flow direction in the oil supply passage, and scrapes solid components present in the oil reservoir POC so as not to enter the inside of the oil supply passage at the time of oil suction. The oil pump 32 is disposed downstream of the oil strainer 31 in the oil flow direction, and serves as a motive power for supplying the oil of the oil reservoir POC to the crankshaft 2 and the rocker arm shaft 3. The oil pump 32 operates in conjunction with the crankshaft 2 to increase the amount of discharged oil in accordance with the increase in the rotational speed of the crankshaft 2.

  The oil filter 33 is disposed downstream of the oil pump 32 in the oil flow direction, and fine solids contained in the oil sucked by the oil pump 32 are filtered off, and the oil after filtration is filtered downstream. To discharge. The bypass valve 34 is provided in the bypass passage connecting the upstream side and the downstream side of the oil filter 33 in the oil passage, and opens when the oil flowing through the oil filter 33 runs short to compensate for the shortage of oil.

  The oil supply pipe 35 is a pipe through which the oil supplied to the crankshaft 2 flows. A plurality of sub galleries 36 are branched from the fuel supply pipe 35. An oil communication path 41 provided in the oil discharge portion 37 is also branched from the oil supply pipe 35. The sub gallery 36 is provided, for example, in a cylinder block, and communicates between the fuel supply pipe 35 and the crank journal 14.

  The oil discharger 37 receives the rotation of the crankshaft 2 and discharges an amount of oil corresponding to the rotation speed of the crankshaft 2 to the inside of the engine 1 to adjust the oil in the oil supply passage to the required pressure. . The oil discharger 37 will be described in detail later.

  In the oil circulation mechanism 5, the oil stored in the oil reservoir POC is sucked through the oil strainer 31 by the operation of the oil pump 32. The sucked oil passes through the oil filter 33 and the bypass valve 34, and is then supplied to the camshaft 4 and the oil supply pipe 35. The oil supplied to the camshaft 4 is used to reduce the frictional resistance between the rocker arm 21 and the cam. On the other hand, the oil supplied to the oil supply pipe 35 flows through the sub gallery 36 and the oil supply passage 15, and is used to reduce the frictional resistance between the crank pin 11 and the connecting rod CR. The oil used to reduce the frictional resistance and the oil discharged from the oil discharging unit 37 are stored in the oil reservoir POC and circulated and used.

  Next, the oil discharging unit 37 will be described in detail. As shown in FIG. 1, the oil discharger 37 is in communication with the downstream side in the oil flow direction with respect to the arrangement position of the oil pump 32 in the oil supply passage. Increase emissions. The oil discharge part 37 includes an oil communication path 41, a rotation member 42, a housing recess 43, and a rotation transmission mechanism 44.

  The oil communication passage 41 communicates the oil supply pipe 35 and the storage recess 43, and supplies the oil of the oil supply pipe 35 to the storage recess 43. For example, as shown in FIG. 3A, the oil communication passage 41 is provided by making a hole in the cylinder block CB. The oil supply pipe 35 is disposed downstream of the oil pump 32 in the oil flow direction. Therefore, the oil communication passage 41 communicates with the oil supply passage on the downstream side of the position where the oil pump 32 is disposed.

  The rotating member 42 is rotated at a rotational speed proportional to the rotational speed of the crankshaft 2 and discharges the oil supplied to the housing recess 43 in an amount corresponding to the rotational speed. As shown in FIG. 2A, the rotation member 42 includes a rotation shaft 51, a driven gear 52 provided at one end of the rotation shaft 51, and a head 53 provided at the other end of the rotation shaft 51. As shown in FIG. 3A, the rotating shaft 51 is rotatably attached to a bearing 54 provided on the cylinder block CB. The driven gear 52 protrudes outward beyond the cylinder block CB, and a drive belt 44b provided in the rotation transmission mechanism 44 meshes with the outer peripheral surface thereof. In the present embodiment, the driven gear 52 is detachably attached to the rotation shaft 51 and fixed by a set screw (not shown) or the like.

  As shown in FIG. 2A, the head portion 53 includes a substrate 54 and a cylindrical wall 55, and is rotated together with the rotation shaft 51. The substrate 54 has a circular plate shape and is joined to the other end of the rotating shaft 51. The cylindrical wall 55 has its proximal end joined to the outer peripheral edge of the substrate 54. Therefore, the tip of the head 53 that is opposite to the substrate 54 is open. The head 53 is provided with a discharge mechanism 56 for increasing the size of the gap through which the oil passes in accordance with the increase in the rotational speed of the rotating member 42. The discharge mechanism 56 will be described later.

  As shown in FIG. 3A, the storage recess 43 is a recess in which the head portion 53 of the rotation member 42 is stored, and is provided in series with the bearing 54 for the rotation shaft 51. A bearing member 45 made of cylindrical metal is fitted on the inner peripheral surface of the housing recess 43. The inner diameter of the bearing member 45 is slightly larger than the outer diameter of the head 53 (cylindrical wall 55) of the rotating member 42. Further, since the head portion 53 and the bearing member 45 are arranged concentrically, a predetermined gap S is provided over the entire circumference between the outer peripheral surface of the head portion 53 and the inner peripheral surface of the bearing member 45. It is formed. An oil hole 45 a penetrating in the thickness direction is provided at a position opposite to the oil communication passage 41 in the bearing member 45. The oil supplied from the oil communication passage 41 flows into the gap S between the head portion 53 and the bearing member 45 by the oil hole 45 a and fills the gap S.

  As shown in FIG. 1, the rotation transmission mechanism 44 includes a drive gear 44 a provided on the crankshaft 2, and a drive belt 44 b stretched between the drive gear 44 a and the driven gear 52 of the rotating member 42. . When the crankshaft 2 rotates, the drive gear 44a rotates. The rotation of the drive gear 44a is transmitted to the driven gear 52 by the drive belt 44b. For this reason, the rotating member 42 is rotated according to the rotation of the crankshaft 2. The rotational speed of the rotating member 42 is determined according to the rotational speed of the crankshaft 2 and the gear ratio of the drive gear 44 a and the driven gear 52.

  Next, the discharge mechanism 56 will be described. As shown in FIG. 2B, the discharge mechanism 56 includes a first discharge mechanism 61 and a second discharge mechanism 71 provided at a position rotated 180 degrees in the circumferential direction from the first discharge mechanism 61.

  The first discharge mechanism 61 includes a first opening 62, a first opening and closing member 63, and a first coil spring 64. The first opening 62 is a rectangular opening that penetrates the wall thickness direction of the cylindrical wall 55. The first opening and closing member 63 is disposed rotatably around the first rotation shaft 65, and closes the first opening 62 so as to open and close. The first opening and closing member 63 is joined to a first bearing 63a fitted to the first rotation shaft 65, a first opening and closing arm 63b joined to the first bearing 63a, and one end of the first opening and closing arm 63b. A first fitting portion 63c fitted to the first opening 62 and a first weight 63d joined to the other end of the first opening / closing arm 63b are provided. The first coil spring 64 is stretched between the first weight 63 d and the support shaft 57, and biases the first weight 63 d toward the support shaft 57 by a contraction force. In the present embodiment, the support shaft 57 is provided upright at the rotation center of the substrate 54.

  When the rotating member 42 is at rest, the first weight 63 d is biased toward the support shaft 57 by the first coil spring 64. As a result, the first opening and closing member 63 pivots about the first pivot shaft 65, and the first fitting portion 63c is urged in the direction of closing the first opening 62. When the rotating member 42 rotates and a centrifugal force stronger than the compression force of the first coil spring 64 acts on the first weight 63 d, the first weight 63 d moves in the outer circumferential direction against the compression force of the first coil spring 64 Do. As a result, the first fitting portion 63c moves in the inner circumferential direction, and a gap through which oil passes between the first fitting portion 63c and the first opening 62 is formed. The area of the gap increases as the centrifugal force acting on the first weight 63d increases.

  The second discharge mechanism 71 includes a second opening 72, a second opening / closing member 73, and a second coil spring 74. The second opening 72 is a rectangular opening that penetrates the wall thickness direction of the cylindrical wall 55. The second opening and closing member 73 is disposed rotatably around the second rotation shaft 75, and closes the second opening 72 so as to open and close. The second opening and closing member 73 is joined to one end of a second bearing 73a fitted to the second rotation shaft 75, a second opening and closing arm 73b joined to the second bearing 73a, and one end of the second opening and closing arm 73b. A second fitting portion 73c fitted to the second opening 72 and a second weight 73d joined to the other end of the second opening / closing arm 73b are provided. The second coil spring 74 is stretched between the second weight 73 d and the support shaft 57, and biases the second weight 73 d toward the support shaft 57 by the contraction force.

  When the rotating member 42 is at rest, the second weight 73 d is urged toward the support shaft 57 by the second coil spring 74. As a result, the second opening and closing member 73 pivots about the second pivot shaft 75, and the second fitting portion 73c is biased in the direction to close the second opening 72. When the rotating member 42 rotates and a centrifugal force stronger than the compression force of the second coil spring 74 acts on the second weight 73 d, the second weight 73 d moves in the outer circumferential direction against the compression force of the second coil spring 74 Do. As a result, the second fitting portion 73 c moves in the inner circumferential direction, and a gap through which oil passes between the second fitting portion 73 c and the second opening 72 is formed. The area of this gap increases as the centrifugal force acting on the second weight 73d increases.

  Next, the operation of this embodiment will be described.

  Since the crankshaft 2 is stationary when the engine 1 is stopped, the rotating member 42 provided in the oil discharging unit 37 also becomes stationary. As shown in FIGS. 3A and 3B, in the stationary state of the rotating member 42, in the first discharging mechanism 61, the first weight 63d is urged toward the support shaft 57 by the first coil spring 64. The fitting portion 63 c is biased in the direction of closing the first opening 62. Similarly, in the second discharge mechanism 71, the second weight 73d is biased toward the support shaft 57 by the second coil spring 74, and the second fitting portion 73c is biased in the direction of closing the second opening 72. Further, the oil pump 32 is stopped, but the oil communication path 41 is filled with oil. Therefore, the oil flowing in through the oil hole 45 a fills the gap S between the head portion 53 of the rotating member 42 and the bearing member 45.

  When the engine 1 is started and rotated at a low speed such as idling, the rotating member 42 is also rotated at a low speed. During the low speed rotation, the centrifugal force acting on the first weight 63 d and the second weight 73 d is smaller than the biasing force of the first coil spring 64 and the second coil spring 74. Therefore, as in the case of stopping the engine 1, the first fitting portion 63c is urged in the direction of closing the first opening 62, and the second fitting portion 73c is urged in the direction of closing the second opening 72. . As the crankshaft 2 rotates, the oil pump 32 sends out oil, and the oil pressure rises. Here, since the gap S between the head 53 of the rotating member 42 and the bearing member 45 is extremely narrow, the oil remains in the gap S. Therefore, the oil delivered from the oil pump 32 is supplied to the crankshaft 2 and the rocker arm shaft 3 and is not discharged from the oil discharging portion 37.

  When the rotational speed of the crankshaft 2 increases, the rotational speed of the rotating member 42 also increases. As the rotational speed increases, the centrifugal force acting on the first weight 63 d and the second weight 73 d also increases. As shown in FIGS. 4A and 4B, when the centrifugal force acting on the first weight 63d and the second weight 73d becomes higher than the compression force of the first coil spring 64 and the second coil spring 74, the first weight 63d is obtained. The second weight 73d moves in the outer circumferential direction. As a result, the first fitting portion 63c and the second fitting portion 73c move in the inner circumferential direction, and therefore, between the first fitting portion 63c and the first opening 62, and the second fitting portion 73c and the second The clearances X1 and X2 are formed between the opening 72 and the opening 72, respectively.

  Since the pressure of the oil is increased by the operation of the oil pump 32, the oil in the oil communication passage 41 is separated by the gap X1 between the first fitting portion 63c and the first opening 62, and the second fitting portion 73c and the second The gas flows into the inner space of the head 53 through the gap X2 of the opening 72, and is discharged to the inside of the engine 1 from the tip of the head 53. As described above, by discharging the oil through the oil communication passage 41 and the rotating member 42, the pressure of the oil on the downstream side of the oil pump 32 can be reduced. Thus, the oil pressure can be optimized.

  When the rotational speed of the crankshaft 2 further increases, the gap X1 on the first opening 62 side and the gap X2 on the second opening 72 side are enlarged. Along with this, the amount of oil discharged through the rotating member 42 (oil discharger 37) also increases. For this reason, an excessive increase in the oil pressure can be suppressed, and the oil pressure can be adjusted to be suitable for the rotational speed of the crankshaft. For example, as shown by a symbol OP1 in FIG. 5, the oil pressure can be adjusted to be proportional to the rotational speed of the crankshaft 2. In addition, by changing the gear ratio of the drive gear 44a and the driven gear 52, it is possible to easily adjust the relationship between the rotational speed of the crankshaft 2 and the oil pressure as indicated by reference numerals OP2 and OP3.

  The above description of the embodiments is for the purpose of facilitating the understanding of the present invention, and does not limit the present invention. The present invention can be modified and improved without departing from the gist thereof, and the present invention includes the equivalents thereof.

  In the above embodiment, regarding the configuration of the oil discharge portion 37, the cylindrical wall 55 is provided on the head portion 53 of the rotating member 42, and the first opening 62 and the second opening 72 are respectively the first opening / closing member 63 and the second opening / closing member Although it was made to open and close by 73, it is not limited to this composition. Other configurations may be employed as long as the amount of oil discharged from the oil communication passage 41 can be adjusted according to the rotation of the rotation member 42.

  In the above embodiment, the oil discharge portion 37 is disposed near the outer wall of the engine 1 in the above embodiment, but if it is communicated with the oil pump 32 on the downstream side in the oil flow direction, It may be a place. In addition, it is preferable to provide in the cylinder block CB from a viewpoint of adjusting oil pressure by discharging oil.

  The rotation transmission mechanism 44 may have another configuration as long as the rotation of the crankshaft 2 can be transmitted to the rotation member 42. For example, a plurality of spur gears may be combined, or a combination of a chain and a sprocket may be used.

  Although the diesel engine 1 was illustrated in the above-mentioned embodiment regarding an internal-combustion engine, the present invention is applicable if it supplies oil through an oil supply passage.

DESCRIPTION OF SYMBOLS 1 ... Diesel engine, 2 ... Crankshaft, 3 ... Rocker arm shaft, 4 ... Camshaft, 5 ... Oil circulation mechanism, 11 ... Crank pin, 12 ... Crank arm, 13 ... Crank throw, 14 ... Crank journal, 15 ... Refueling Road, 21 ... Rocker arm, 22 ... Oil flow path, 23 ... Cam, 31 ... Oil strainer, 32 ... Oil pump, 33 ... Oil filter, 34 ... Bypass valve, 35 ... Oil supply pipe, 36 ... Sub gallery, 37 ... Oil Discharge part, 41: oil communication passage, 42: rotation member, 43: storage recess, 44: rotation transmission mechanism, 44a: drive gear, 44b: drive belt, 45: bearing member, 45a: oil hole, 51: rotation shaft, 52: driven gear, 53: head, 54: substrate, 55: cylindrical wall, 56: discharge mechanism, 57: support shaft, 61: first discharge mechanism, 62: first opening, 63: first Closing member, 63a: first bearing, 63b: first opening / closing arm, 63c: first fitting portion, 63d: first weight, 64: first coil spring, 65: first rotation shaft, 71: second discharging mechanism , 72: second opening, 73: second opening / closing member, 73a: second bearing, 73b: second opening / closing arm, 73c: second fitting portion, 73d: second weight, 74: second coil spring, 75: second 2 Rotating shaft, PS ... Piston, CR ... Connecting rod, POC ... Oil reservoir, S ... Clearance between head and bearing member, X1, X2 ... Clearance of discharge mechanism

Claims (1)

An oil pump that is disposed in the oil supply path and increases the oil discharge amount in accordance with an increase in the rotational speed of the crankshaft;
The oil pump is connected downstream of the oil pump in the oil supply direction in the oil flow direction, the rotation of the crankshaft is transmitted, and the amount of oil discharged is reduced according to the increase in the rotation speed of the crankshaft. Bei example an oil discharge section to increase, and
The oil discharge unit is
A rotating shaft that is rotated by the crankshaft, and a rotating member provided with the rotating shaft and having a head that rotates with the rotating shaft;
A discharge mechanism that is provided at the head of the rotating member and increases an area of a flow path through which oil passes according to an increase in the number of rotations of the rotating member;
A storage recess in which the head of the rotating member is rotatably stored;
An oil communication path communicating with the oil supply path and the storage recess,
The discharge mechanism is
A cylindrical wall provided with an opening penetrating the wall thickness direction;
An oil pressure adjustment mechanism for an internal combustion engine , comprising: an opening / closing member that closes the opening so as to be openable / closable and increases an area of a gap formed between the opening and the opening according to an increase in the rotational speed of the rotating member .

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