JP2005282510A - Control mechanism of lash adjuster oil passage - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a control mechanism of a lash adjuster oil passage capable of preventing abnormal behavior. <P>SOLUTION: This control mechanism of the lash adjuster oil passage comprises a hydraulic lash adjuster 100, the lash adjuster oil passage 99, a main oil passage 98, a Coriolis meter 72 measuring air bubble ratio in the lash adjuster oil passage 99, a solenoid valve 78 capable of connecting and disconnecting the lash adjuster oil passage 99 to and from the main oil passage 98, an auxiliary oil pump 81 capable of circulating oil in the lash adjuster oil passage 99, and an ECU 75 connected to the Coriolis meter 72, the solenoid valve 76, and the auxiliary oil pump 81. When the air bubble ratio in the lash adjuster oil passage 99 is equal to or higher tan a specified value, the ECU 75 closes the solenoid valve 76 to cut off the lash adjuster oil passage 99 and the main oil passage 98 and drive the auxiliary oil pump 81. When the air bubble ratio in the lash adjuster oil passage 99 is less than the specified value, the ECU 75 opens the solenoid valve 76 to connect the lash adjuster oil passage 99 to the main oil passage 98. <P>COPYRIGHT: (C)2006,JPO&NCIPI

Description

  The present invention relates to a control mechanism for a lash adjuster oil passage, and in particular, to provide a control mechanism for a lash adjuster oil passage that can reduce the bubble ratio.

Conventionally, techniques related to lash adjusters are disclosed in, for example, Japanese Patent Laid-Open No. 59-168209 (Patent Document 1), Japanese Patent Laid-Open No. 5-195743 (Patent Document 2), Japanese Patent Laid-Open No. 9-32527 (Patent Document 3). JP-A-63-131878 (Patent Document 4) and JP-A-2-90302 (Patent Document 5).
JP 59-168209 A JP-A-5-195743 JP-A-9-32527 JP-A-63-131878 Japanese Utility Model Publication No. 2-90302

  In patent document 1, since it becomes easy to generate | occur | produce a bubble when hydraulic fluid becomes high temperature, the technique cooled with an oil cooler is disclosed.

  Patent Document 2 discloses a technique for reducing the relief hole when the oil temperature is high and increasing the hydraulic pressure of the main gallery.

  Patent Document 3 discloses a technique for introducing bubble-mixed oil into a gas-liquid separator when bubbles exceed an allowable value.

  Patent Document 4 discloses a technique for crushing bubbles in gear pump oil with high-pressure oil.

  Patent Document 5 discloses that the amount of bubbles in the lash adjuster increases when the engine is heavily loaded and when the engine rotates at high speed.

  However, any of the above-described techniques has a problem that once a bubble is generated, the bubble bites into the hydraulic lash adjuster, and the hydraulic lash adjuster excessively sinks.

  Accordingly, the present invention has been made to solve the above-described problems, and a lash adjuster oil passage that can maintain the function of a hydraulic lash adjuster even when many bubbles are generated. An object is to provide a control mechanism.

  The control mechanism of the lash adjuster oil passage according to the present invention includes a hydraulic lash adjuster, a lash adjuster oil passage that supplies oil to the hydraulic lash adjuster, a main oil passage that supplies oil to the lash adjuster oil passage, and a lash A measurement unit for measuring the bubble rate in the adjuster oil passage, a valve capable of connecting and disconnecting the lash adjuster oil passage and the main oil passage, a pump capable of circulating the oil in the lash adjuster oil passage, And a control unit connected to the measurement unit, the valve, and the pump. If the bubble rate in the lash adjuster oil path measured by the measuring unit is equal to or greater than a predetermined value, the control unit closes the valve to cut the lash adjuster oil path and the main oil path and drive the pump. If the bubble rate in the lash adjuster oil passage measured by the measuring unit is less than a predetermined value, the control unit opens the valve to connect the lash adjuster oil passage and the main oil passage.

  In the control mechanism of the lash adjuster oil passage configured as described above, if the bubble rate in the lash adjuster oil passage measured by the measuring unit is equal to or greater than a predetermined value, the control means closes the valve and the lash adjuster oil passage and the main oil passage And the pump is driven, the lash adjuster oil passage is isolated from the main oil passage. Thereby, supply of the bubble from a main oil path can be interrupted | blocked, and mixing of the bubble beyond it can be prevented.

  In other words, the conventional technology cannot guarantee reliable operation under severe conditions such as high rotation and high oil temperature. The reason for this is that generally gas-liquid separation takes time, and there remains a question as to whether a reliable air venting effect can be expected at high revolutions and high oil temperatures. In the present invention, rather than reducing the bubble ratio, a countermeasure for the occurrence of abnormal behavior of the hydraulic lash adjuster is shown. According to the present invention, reliable operation of the hydraulic lash adjuster can be ensured.

  According to the present invention, reliable operation of the hydraulic lash adjuster can be ensured, and a highly reliable lash adjuster oil passage can be provided.

  Embodiments of the present invention will be described below with reference to the drawings. In the following embodiments, the same or corresponding parts are denoted by the same reference numerals, and description thereof will not be repeated.

(Embodiment 1)
FIG. 1 is a cross-sectional view of an engine head having a hydro lash adjuster. With reference to FIG. 1, a hydro lash adjuster 100 is provided in the engine head 1. In the engine head 1, a hole 11 is provided in the head block, and a hydro lash adjuster 100 is fitted in the hole 11. The inside of the hydro lash adjuster 100 is filled with 100 L of oil.

  The hydro lash adjuster 100 is in contact with the rocker arm 20. The rocker arm 20 uses the hydro lash adjuster 100 as a fulcrum and receives the force from the cam 30 to reciprocate the valve 50. That is, when the cam 30 rotates, the contact point between the hydro lash adjuster 100 and the rocker arm 20 becomes a fulcrum, and the valve 50 reciprocates. The valve 50 is urged away from the combustion chamber 70 by the valve spring 40, and even after being pushed down by the cam 30, the valve 50 returns to its original position by the action of the valve spring 40. The tip of the valve 50 is provided near the boundary between the intake 60 and the combustion chamber 70.

  FIG. 2 is a sectional view showing the hydro lash adjuster in FIG. 1 in detail. Referring to FIG. 2, the hydro lash adjuster 100 defines a high pressure chamber 120 and a low pressure chamber 121, and is fitted into a housing 101 having an opening 101 h connected to the low pressure chamber 121, the opening 101 h, and as a separate member. And a plunger 102 that contacts the rocker arm 20.

  The casing 101 has a box shape, and a low-pressure chamber 121 and a high-pressure chamber 120 are provided in its internal space. In FIG. 2, the internal space of the housing 101 is a rectangular region, but is not limited to this, and the cross section may be round (round). Moreover, although the housing | casing 101 is provided in a cylindrical shape, a rectangular tube shape may be sufficient.

  A plunger 102 is fitted into the opening 101h of the housing 101 so as to be movable in the vertical direction. The plunger 102 is slidable with the inner peripheral wall of the housing 101 constituting the opening 101h, and can move in a direction approaching the bottom 101u of the housing 101 and a direction away from the bottom 101u. The plunger 102 is fitted into the recess of the rocker arm, and the tip of the plunger 102 is engaged with the rocker arm 20.

  The plunger 102 is provided with a rod-like member 103 for pushing the check ball 105. One end of the rod-shaped member 103 contacts the plunger 102, and the other end contacts the check ball 105. Due to the presence of the rod-shaped member 103, it is possible to directly transmit the pressure in the direction indicated by the arrow 104 to the check ball 105.

  In the internal space, a partition plate 106 that partitions the high-pressure chamber 120 and the low-pressure chamber 121 is provided. The partition plate 106 is provided with an opening 106h, and the low pressure chamber 121 and the high pressure chamber 120 are connected by the opening 106h. The partition plate 106 receives a check ball 105 as a check valve. The check ball 105 seals the opening 106h and functions to prevent the high-pressure oil 100L on the high-pressure chamber 120 side from flowing into the low-pressure oil 100L side in the low-pressure chamber 121.

  A force (a force in the direction opposite to the direction indicated by the arrow 104) is applied to the check ball 105 through the opening 106h so that the oil 100L on the high pressure chamber 120 side flows to the low pressure chamber 121 side. However, since the check ball 105 is held down by the rod-like member 103, the check ball 105 does not move to the plunger 102 side. Thereby, the oil 100L on the high pressure chamber 120 side can be prevented from flowing into the low pressure chamber 121 side.

  The partition plate 106 is provided so as to be movable in the vertical direction, and a spring 107 is disposed in the high pressure chamber 120 so as to support the partition plate 106. The spring 107 is interposed between the partition plate 106 and the bottom 101u, and has a structure capable of changing the volume in the high-pressure chamber 120. The spring 107 serves to transmit the force received from the partition plate 106 to the bottom 101u.

  Next, the operation of the hydro lash adjuster as described above will be described.

  The hydro lash adjuster 100 for adjusting the clearance between the swing arm rocker arm 20 of the overhead cam and the valve 50 has a slidable plunger 102 and introduces oil 100L composed of engine oil, The entire length is changed, and the valve gap is automatically adjusted (the gap is always kept at zero). The operation of the hydro lash adjuster 100 will be described as follows.

(1) Flow of Oil When the engine rotates, oil 100L is introduced from the hole 11 around the hydro lash adjuster 100 into the low pressure chamber 121 through a hole (not shown) provided in the housing 101. A part of the oil 100L lubricates a contact portion between the plunger 102 and the rocker arm 20. When the hydraulic pressure in the high pressure chamber 120 decreases, the check ball 105 is moved to supply oil 100L into the high pressure chamber 120.

(2) During Cam Lift FIG. 3 is a cross-sectional view of the engine head shown for explaining the cam lift. Referring to FIGS. 3 and 2, when cam 30 tries to push down rocker arm 20, rocker arm 20 tries to push down valve 50 and plunger 102 at the same time. However, when the plunger 102 is pushed down, the high pressure chamber 120 is sealed by the check ball 105 and thus becomes high pressure. The plunger 102 does not drop, and the rocker arm 20 moves with the contact point between the rocker arm 20 and the plunger 102 as a fulcrum. Press down.

(3) During cam base cycle When the cam 30 rotates and does not push down the rocker arm 20, the return spring 107 in the high pressure chamber 120 pushes up the plunger 102 as shown in FIG. Prevent gaps from forming.

  FIG. 4 is a block diagram of a control mechanism for the lash adjuster oil passage according to the first embodiment of the present invention. Referring to FIG. 4, the engine head 1 is provided with a plurality of hydro lash adjusters 100, and these hydro lash adjusters 100 are connected to each other by a lash adjuster oil passage 99. The lash adjuster oil passage 99 is provided with a Coriolis meter 72 for measuring how much air bubbles are mixed in the oil in the lash adjuster oil passage 99. Further, an auxiliary oil pump 81 capable of circulating the oil in the lash adjuster oil passage 99 is connected to the lash adjuster oil passage 99. An auxiliary oil pump 81 is connected to the plurality of hydro lash adjusters 100 connected in series.

  The auxiliary oil pump 81 is connected to the electromagnetic valve 76, and the electromagnetic valve 76 is connected to the main oil path 98. The main oil path 98 connects the oil pan 82, the oil pump 83, the oil filter 84, and the block 85, and serves as a main flow path for engine oil. Oil in the main oil passage 98 is circulated by the oil pump 83. An electromagnetic valve 76 provided at the boundary between the main oil path 98 and the lash adjuster oil path 99 can cut and connect the lash adjuster oil path 99 from the main oil path 98. The main oil passage 98 also lubricates the variable valve timing mechanism inlet 93, the chain 92, and the variable valve timing mechanism outlet 91. Further, the cam bearing 31 is also lubricated by the main oil passage 98.

  An ECU (Engine Unit Control) 75 is connected to the Coriolis meter 72, the auxiliary oil pump 81, and the electromagnetic valve 76, and can control these operations.

  FIG. 5 is a block diagram of the Coriolis meter. Referring to FIG. 5, a Coriolis meter 72 includes a mass flow meter (Coriolis meter) 301, a pressure adjustment valve 302 that adjusts the amount of oil flowing into the mass flow meter 301, and a capacity meter for measuring the capacity. Meter (PD meter) 305, pressure adjustment valve 306 connected to capacity meter 305, pressure sensor 303 for detecting pressure, temperature sensor 304 for detecting temperature, and pressure calculation for calculating pressure A circuit 311, a temperature calculation circuit 312 for calculating the temperature, and a central calculation circuit 313 that integrates the information are included. The oil flowing in from the direction indicated by the arrow 321 is adjusted in pressure by the pressure adjusting valve 302 and passes through the mass flow meter 301. Thereafter, the oil passes through the pressure sensor 303, passes through the temperature sensor 304, and then reaches the capacity meter 305. Thereafter, oil is discharged through the pressure regulating valve 306 as indicated by an arrow 322. Using the mass flow meter 301, the pressure sensor 303, the temperature sensor 304, and the volume meter 305, the density of oil is measured, and the density is compared with the initial oil density (density without bubbles). As a result of this comparison, the bubble rate is calculated, and the central processing circuit 313 transmits the bubble rate to the ECU 75.

  FIG. 6 is a flowchart of the control mechanism of the lash adjuster oil passage according to the first embodiment of the present invention. Referring to FIG. 6, first, control of the lash adjuster oil passage is started (step S501).

  The bubble rate in the lash adjuster oil passage 99 is detected by the Coriolis meter 72 shown in FIGS. 4 and 5 (step S502).

  The detected bubble rate is transmitted to the ECU 75, and the ECU 75 determines whether or not the bubble rate is equal to or greater than a predetermined value (step S503).

  If the bubble ratio is equal to or greater than a predetermined value, the ECU 75 sends a signal to the electromagnetic valve 76 so as to cut the oil passage. Specifically, the main oil passage 98 and the lash adjuster oil passage 99 are disconnected by closing the electromagnetic valve 76. At the same time, the ECU 75 sends a signal to drive the auxiliary oil pump 81. As a result, the lash adjuster oil passage 99 is disconnected from the main oil passage 98 (step S504).

  Bubbles in the oil are mainly generated in the oil pan 82. Specifically, since the crankshaft lifts up the oil stored in the oil pan 82, the higher the rotation speed, the harder the crankshaft lifts up the oil. As a result, the oil is foamed, and the foamed oil is supplied from the main oil path 98 to the lash adjuster oil path 99 via the oil pump 83. If the electromagnetic valve 76 is closed, it is possible to prevent oil with much air bubbles from being supplied from the main oil passage 98 to the lash adjuster oil passage 99, and to gradually reduce the bubble ratio of oil in the lash adjuster oil passage 99. .

  If the ECU 75 determines that the bubble rate is less than the predetermined value, the control is once terminated and the process returns to the start (step S505).

  That is, in the present invention, a Coriolis meter 72 as a bubble rate measuring device is disposed at the end of the lash adjuster oil passage 99. Thereby, the bubble rate in oil is always measured. When the bubble ratio exceeds a preset danger value during operation, the auxiliary oil pump 81 is driven simultaneously with closing the electromagnetic valve 76 in accordance with a command from the ECU 75. As a result, the lash adjuster oil passage 99 is disconnected from the main oil passage 98 to prevent further bubbles from entering. If the bubble rate returns to normal, the electromagnetic valve 76 is opened and the auxiliary oil pump 81 is stopped. The auxiliary oil pump 81 does not need to be completely stopped, and the auxiliary oil pump 81 may be moved at a low speed.

  The control mechanism of the lash adjuster oil passage according to the present invention includes a hydro lash adjuster 100 as a hydraulic lash adjuster, a lash adjuster oil passage 99 that supplies oil to the hydro lash adjuster 100, and oil to the lash adjuster oil passage 99. A main oil passage 98 that supplies and lubricates the engine head 1, a Coriolis meter (Coriolis meter) 72 as a measuring unit that measures a bubble rate in the lash adjuster oil passage 99, a lash adjuster oil passage 99 and the main oil passage 98, an electromagnetic valve 76 that can be connected to and disconnected from the 98, an auxiliary oil pump 81 that can circulate oil in the lash adjuster oil passage 99, a Coriolis meter 72, an electromagnetic valve 76, and an auxiliary As a control unit connected to the oil pump 81 And a ECU75. If the bubble ratio in the lash adjuster oil passage 99 measured by the Coriolis meter 72 is equal to or greater than a predetermined value, the ECU 75 closes the electromagnetic valve 76 to disconnect the lash adjuster oil passage 99 and the main oil passage 98 and the auxiliary oil pump 81. Drive. If the bubble rate in the lash adjuster oil passage 99 measured by the Coriolis meter 72 is less than a predetermined value, the ECU 75 opens the electromagnetic valve 76 to connect the lash adjuster oil passage 99 and the main oil passage 98.

  In the control mechanism of the lash adjuster oil passage according to the first embodiment of the present invention configured as described above, the bubble rate in the oil of the lash adjuster oil passage 99 is constantly monitored, and the value is the hydro lash adjuster 100. When it is determined that there is a possibility that an abnormality will occur, the lash adjuster oil passage 99 is disconnected from the main oil passage 98, whereby the abnormal behavior of the hydro lash adjuster 100 can be prevented in advance.

(Embodiment 2)
FIG. 7 is a sectional view of a hydro lash adjuster with a limit switch used in the control mechanism of the lash adjuster oil passage according to the second embodiment of the present invention. FIG. 8 is a block diagram showing a control mechanism for the lash adjuster oil passage according to the second embodiment of the present invention. 7 and 8, in the control mechanism for the lash adjuster oil passage according to the second embodiment of the present invention, the hydro lash adjuster 73 with limit switch for detecting abnormal behavior at the end of the lash adjuster oil passage 99 is shown. Is provided. As shown in FIG. 7, the hydro lash adjuster 73 has a limit switch 180, and the limit switch 180 has a limit switch 180 that operates during abnormal behavior, that is, when the plunger 102 is greatly depressed. In this figure, the limit switch 180 is provided in the high pressure chamber 120, but is not necessarily limited thereto, and the limit switch 180 may be provided on the low pressure chamber 121 side.

  Referring to FIG. 8, hydro lash adjuster 73 is connected to ECU 75, and if limit switch 180 detects an abnormal behavior, the information is immediately transmitted to ECU 75. That is, in the second embodiment, a hydro lash adjuster 73 with a limit switch is provided as a measurement unit that measures the bubble rate in the lash adjuster oil passage 99. If the bubble rate in the lash adjuster oil passage 99 increases, the bubbles mixed into the hydro lash adjuster 73 also increase. When bubbles are mixed into the hydro lash adjuster 73, the bubbles are first introduced into the low pressure chamber 121 and further flow into the high pressure chamber 120 via the check ball 105. When bubbles increase in the high pressure chamber 120, when pressure is applied to the plunger 102, the oil in the high pressure chamber 120 contracts, and the partition plate 106 and the plunger 102 are abnormally lowered as shown in FIG. As a result, the limit switch 180 is activated.

  The control mechanism for the lash adjuster oil passage according to the second embodiment of the present invention configured as described above has the same effect as the control mechanism for the lash adjuster oil passage according to the first embodiment.

(Embodiment 3)
FIG. 9 is a block diagram of a control mechanism for the lash adjuster oil passage according to the third embodiment of the present invention. Referring to FIG. 9, in the control mechanism for the lash adjuster oil passage according to the third embodiment of the present invention, a hydraulic sensor 71 is disposed at the end of lash adjuster oil passage 99, and this hydraulic sensor 71 is connected to ECU 75. Has been. The oil pressure sensor 71 can monitor the oil pressure in the lash adjuster oil passage 99, thereby indirectly measuring the bubble rate in the lash adjuster oil passage 99. That is, when air bubbles are mixed into the oil in the lash adjuster oil passage 99, the hydraulic pressure decreases. The hydraulic pressure sensor 71 can measure this decrease in hydraulic pressure. If the oil pressure measured by the oil pressure sensor 71 exceeds a predetermined value, the ECU 75 closes the electromagnetic valve 76 and drives the auxiliary oil pump 81. That is, in the third embodiment, a hydraulic sensor 71 is provided as a measurement unit that measures the bubble rate in the lash adjuster oil passage.

  The control mechanism for the lash adjuster oil passage according to the third embodiment configured as described above has the same effect as the control mechanism for the lash adjuster oil passage according to the first embodiment.

(Embodiment 4)
FIG. 10 is a block diagram of a control mechanism for the lash adjuster oil passage according to the fourth embodiment of the present invention. In the present invention, the bubble rate at the end of the lash adjuster oil passage is measured, or the oil pressure at the end of the lash adjuster oil passage is measured. If the measured value is less than or equal to a preset danger value (predetermined value), the process passes. That is, it is not necessary to perform control. If the risk value is exceeded, the bubble rate is reduced by the following measures.

  Solution A: Disconnect the lash adjuster oil passage from the main oil passage.

  Action B: Stop chain lubrication. Alternatively, control of variable valve timing is stopped, or shower lubrication is stopped.

  Countermeasure C: Increase the relief pressure using a variable relief pressure valve provided at the end of the lash adjuster oil passage.

  Countermeasure D: Increase the relief pressure of the relief pressure valve in the main oil passage.

  Countermeasure E: Increase the cooling efficiency of the oil cooler.

  Countermeasure F: Decrease the engine speed.

  Countermeasure A is as described in the first to third embodiments.

  Regarding measure B, the hydraulic pressure of the lash adjuster oil passage is increased by stopping chain lubrication, stopping variable valve timing (VVT) control, stopping shower lubrication, and the like. This is based on the fact that even if the bubble ratio increases, the hydraulic lash adjuster is unlikely to cause abnormal behavior (air biting) if the hydraulic pressure is high. Lubrication is stopped by closing the electromagnetic valve.

  Regarding Measure C, a variable relief pressure valve is attached to the end of the lash adjuster oil passage, and the oil pressure in the lash adjuster oil passage is increased by increasing the relief pressure when the bubble rate is abnormal.

  For measure D, the relief pressure valve of the main oil passage is made the same as measure C above, and the relief pressure is increased when the bubble rate is abnormal, thereby increasing the hydraulic pressure of the lash adjuster oil passage.

  As for measure E, the oil pressure of the lash adjuster oil passage is increased by increasing the cooling efficiency of the oil cooler when the bubble rate is abnormal. An example of the variable oil cooler is a shutter-type oil cooler. When oil is rapidly cooled, the shutter is controlled so that sufficient cooling air is applied.

  As countermeasure F, the engine speed is decreased when the bubble rate is abnormal. Thereby, it is possible to prevent bubbles from being generated by the oil in the oil pan, and to reduce the bubble rate.

  By using the above control alone or in combination, even when the bubble ratio is high, a sufficient oil pressure in the lash adjuster oil passage can be ensured, and abnormal behavior of the hydro lash adjuster can be prevented.

  Although the embodiment of the present invention has been described above, the embodiment shown here can be variously modified. First, as a field to which the present invention is applied, a control mechanism for a lash adjuster oil passage using a hydro lash adjuster has been described. However, the present invention is not limited to this, and a hydraulic tappet provided between a valve and a cam, overhead The present invention can also be applied to a hydraulic valve lifter (hydraulic lifter), a sealed hydraulic lifter, or the like provided in a valve (OHV) engine.

  Moreover, as an engine to which the present invention is applied, not only a gasoline engine but also a diesel engine may be used.

  Further, the present invention can be applied to various engines such as a series type, a V type, a W type, and a horizontally opposed type as engine types.

  Furthermore, the present invention can be applied as a control mechanism for a lash adjuster oil passage not only for automobile engines but also for aircraft engines, generator engines, and other industrial machine engines.

  In the present invention, when the bubble rate in the oil of the lash adjuster oil passage exceeds a predetermined value, the hydro lash adjuster is reliably operated even at high speed and high load by separating the lash adjuster oil passage from the main oil passage. be able to.

  The embodiment disclosed this time should be considered as illustrative in all points and not restrictive. The scope of the present invention is defined by the terms of the claims, rather than the description above, and is intended to include any modifications within the scope and meaning equivalent to the terms of the claims.

  The present invention can be used in the field of a control mechanism for an engine hydraulic lash adjuster oil passage.

It is sectional drawing of the engine head which has a hydro lash adjuster. It is sectional drawing which shows the hydro lash adjuster in FIG. 1 in detail. It is sectional drawing of the engine head shown in order to demonstrate the time of a cam lift. It is a block diagram of the control mechanism of the lash adjuster oil path according to Embodiment 1 of this invention. It is a block diagram of a Coriolis meter. It is a flowchart of the control mechanism of the lash adjuster oil path according to Embodiment 1 of this invention. It is sectional drawing of the hydro lash adjuster with a limit switch used with the control mechanism of the lash adjuster oil path according to Embodiment 2 of this invention. It is a block diagram of the control mechanism of the lash adjuster oil path according to Embodiment 2 of this invention. It is a block diagram of the control mechanism of the lash adjuster oil path according to Embodiment 3 of this invention. It is a block diagram of the control mechanism of the lash adjuster oil path according to Embodiment 4 of this invention.

Explanation of symbols

  1 engine head, 20 rocker arm, 30 cam, 40 valve spring, 50 valve, 60 intake, 70 combustion chamber, 72 Coriolis meter, 75 ECU, 76 electromagnetic valve, 98 main oil path, 99 lash adjuster oil path, 100 hydro lash adjuster .

Claims (1)

Hydraulic lash adjuster,
A lash adjuster oil passage for supplying oil to the hydraulic lash adjuster;
A main oil passage for supplying oil to the lash adjuster oil passage;
A measuring unit for measuring a bubble rate in the lash adjuster oil passage;
A valve capable of connecting and disconnecting the lash adjuster oil passage and the main oil passage;
A pump capable of circulating oil in the lash adjuster oil passage;
A control unit connected to the measurement unit, the valve and the pump;
If the bubble rate in the lash adjuster oil passage measured by the measuring unit is equal to or greater than a predetermined value, the control unit closes the valve to cut the lash adjuster oil passage and the main oil passage and Drive,
If the bubble rate in the lash adjuster oil path measured by the measuring unit is less than a predetermined value, the control unit opens the valve to connect the lash adjuster oil path and the main oil path, the lash adjuster oil path Control mechanism.

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