JP2021017882A - Valve gear - Google Patents

Abstract

To provide a valve gear that can control a member for regulating a valve clearance from being worn.SOLUTION: A valve gear 10 includes a regulating member 50 for regulating a valve clearance with hydraulic control. The regulating member 50 is provided with multiple pressure receiving parts 51 for receiving load from a side of a valve 20 while dispersing the load when a valve moves.SELECTED DRAWING: Figure 1

Description

The present invention relates to a valve gear.

The valve gear disclosed in Patent Document 1 includes a tappet for an internal combustion engine such as an automobile engine. This tappet includes a lash adjuster and a tappet body into which the lash adjuster is inserted and incorporated.

In the above valve gear, when the cam rotates, the tappet body in contact with the cam slides and displaces the tappet guide hole in the vertical direction, and the push rod is moved up and down via the lash adjuster. The valve clearance is automatically adjusted by damping and transmitting the cam lift force to the push rod and rocker arm via the lash adjuster.

The valve gear disclosed in Patent Document 2 has a configuration in which a pair of intake valves are opened and closed via a valve bridge.

International Publication No. 2018/147092 JP-A-2009-57936

By the way, in the configuration disclosed in Patent Document 1, one lash adjuster receives the load from the valve side at the time of valve operation. When the valve gear has two valves as in Patent Document 2, the load acting on the lash adjuster from the valve side at the time of valve operation becomes larger. When a large load is applied to the lash adjuster, the portion of the lash adjuster that receives the load may be excessively worn, and there is room for improvement.

The present invention has been completed based on the above circumstances, and an object of the present invention is to provide a valve operating device capable of suppressing wear of a member for adjusting valve clearance.

The valve gear according to the present invention is a valve gear including an adjusting member for adjusting the valve clearance by hydraulic control, and the adjusting member receives a plurality of pressures to be distributed and received from the valve side at the time of valve operation. A part is provided.

According to this valve gear, the load received by each of the plurality of pressure receiving portions can be reduced as compared with the configuration in which the load from the valve side is received by a single pressure receiving portion during valve operation. As a result, wear of the pressure receiving portion can be suppressed.

It is a figure which shows the valve gear which concerns on Example 1 of this invention. It is an enlarged view which shows the adjustment member provided in the tappet of FIG. It is an enlarged view which shows the adjustment member provided in the tappet which concerns on Example 2. FIG.

Preferred embodiments of the present invention are shown below.
The adjusting member may include a plurality of hydraulic control units, and each of the plurality of hydraulic control units may have the pressure receiving unit. According to this configuration, even when the hydraulic control by one of the plurality of hydraulic control units is malfunctioning, the valve clearance can be adjusted by the hydraulic control by the other hydraulic control units.

The hydraulic control unit may be a lash adjuster. The rush adjuster has a bottomed tubular body and a plunger that is reciprocally inserted into the body, and a low-pressure chamber in which hydraulic oil is stored is provided in the plunger. In the body, a high pressure chamber is formed which is partitioned from the low pressure chamber by the bottom wall of the plunger and is filled with the hydraulic oil, and the low pressure chamber and the high pressure chamber are formed on the bottom wall of the plunger. A valve hole communicating with the valve hole may be provided so as to penetrate the valve hole, and a valve body for opening and closing the valve hole may be provided in the high-pressure chamber. The top of the plunger may constitute the pressure receiving portion. According to this configuration, the adjusting member can be easily configured by using a plurality of lash adjusters.

The valve gear includes a rocker arm that swings around a rocker shaft to open and close the valve arranged on one end side, and a push rod that supports the other end side of the rocker arm on the upper end side. A tappet that reciprocally displaces while sliding on the inner peripheral surface of the tappet bore according to the rotation of the cam to transmit power to the push rod side may be further provided. The adjusting member may be provided on the tappet, and a plurality of pressure receiving portions may support the lower end side of the push rod. According to this configuration, it is easy to apply the adjusting member in the OHV type valve gear.

The valve gear may further include an intervening member interposed between the push rod and the plurality of pressure receiving portions. According to this configuration, it is possible to prevent the structure of the push rod from becoming complicated by interposing the intervening member, and it is possible to transmit the load from the push rod to the plurality of lash adjusters with a simple configuration.

The intervening member may be in sliding contact with the sliding contact surface in the tappet bore when adjusting the valve clearance. According to this configuration, since the posture of the intervening member is defined by the sliding contact surface, the operation of the intervening member is stabilized, and the load can be transmitted from the intervening member to the plurality of pressure receiving portions in a well-balanced manner.

The intervening member may have an oil passage provided so as to penetrate from the push rod side toward the adjusting member side. According to this configuration, even if the intervening member is interposed between the push rod and the plurality of pressure receiving portions, the lubricating oil (hydraulic oil) can be supplied to the adjusting member through the oil passage of the intervening member. it can.

The tappet may be rotatable in the circumferential direction in the tappet bore. According to this configuration, the adjusting member can be displaced in the circumferential direction in the tappet bore, and it is possible to suppress wear of a specific pressure receiving portion among the plurality of pressure receiving portions of the adjusting member.

<Example 1>
Example 1 of the present invention will be described with reference to FIGS. 1 and 2. The valve gear 10 according to the first embodiment constitutes a valve lifter for an OHV (OverHead Valve) type engine.

As shown in FIG. 1, the valve gear 10 includes a valve 20, a rocker arm 30, a push rod 40, a tappet 45, and an adjusting member 50 provided on the tappet 45. In the valve gear 10, the valve 20 is incorporated so that the intake or exhaust port 92 of the cylinder head 91 can be opened and closed, and the tappet 45 is incorporated so as to be reciprocally displaceable in the tappet bore 95 of the cylinder block (housing) 94. The valve gear 10 is used, for example, in a diesel engine in which two valves 20 are provided for each cylinder at an intake port and an exhaust port. The valve gear 10 is configured to open and close two valves 20 arranged side by side in the intake or exhaust port 92 by a common rocker arm 30 via a valve bridge 22.

The upper end of the valve 20 is arranged so as to project above the cylinder head 91. The valve 20 is slidably inserted into the valve guide hole 93 in the vertical direction, and is urged in the valve closing direction (direction in which one end 31 of the rocker arm 30 is lifted) by an urging member 21 such as a coil spring. The two valves 20 arranged side by side are arranged so as to support both ends of the valve bridge 22.

The rocker arm 30 has a form extending in the length direction from one end 31 to the other 32. The rocker arm 30 is a member that swings around a rocker shaft 96 to open and close a valve 20 arranged on one end 31 side. One end 31 of the rocker arm 30 comes into contact with an intermediate portion of the valve bridge 22 (a portion between both ends supported by two valves 20). The rocker shaft 96 penetrates an intermediate portion (a portion between one end portion 31 and the other end portion 32) of the rocker arm 30. An adjust screw 33 is provided on the other end 32 of the rocker arm 30. The adjusting screw 33 penetrates the other end 32 of the rocker arm 30 and is screwed into the nut 34, and the amount of protrusion downward from the other end 32 of the rocker arm 30 can be adjusted according to the screwing into the nut 34. ing. At the lower end of the adjusting screw 33, a hemispherical bearing recess 35 that opens downward is provided. The bearing recess 35 has a radius of curvature larger than the upper end 41 (convex spherical surface) of the push rod 40, which will be described later, and abuts on the upper end 41 of the push rod 40.

The push rod 40 is a member that transmits power to the other end 32 side of the rocker arm 30 on the upper end 41 side. The push rod 40 has an elongated rod shape in the vertical direction. The upper end 41 and the lower end 42 of the push rod 40 are formed in a convex spherical shape to be a pressure receiving surface that receives a load. The upper end 41 of the push rod 40 slidably contacts the inner surface of the bearing recess 35 of the rocker arm 30. The lower end 42 of the push rod 40 slidably contacts the inner surface of the upper recess 56 of the intervening member 55, which will be described later. The push rod 40 has an oil passage 43 provided so as to penetrate in the axial direction. The oil passage 43 supplies lubricating oil (hydraulic oil) from the rocker arm 30 side to the intervening member 55 side described later. The oil passage 43 branches near the lower end 42 of the push rod 40 to form a lubricating oil path leading to a plurality of lash adjusters 60 described later.

The tappet 45 is a member that reciprocates while sliding on the inner peripheral surface of the tappet bore 95 in response to the rotation of the cam 97 to transmit power to the push rod 40 side. The tappet 45 is rotatable in the circumferential direction in the tappet bore 95. The tappet 45 has a bottomed tubular tappet body 46, and an adjusting member 50 is provided in the tappet body 46. The lower surface of the tappet body 46 is a cam sliding surface that the cam 97 arranged below is slidably contacted. The outer peripheral surface of the tappet body 46 slidably contacts the inner peripheral surface of the tappet bore 95.

The tappet main body 46 has a first accommodating space for accommodating the adjusting member 50, and a second accommodating space above the first accommodating space for accommodating the intervening member 55 described later. The peripheral wall surface 47 of the first accommodation space is made to be in contact with the outer peripheral surface of the adjusting member 50, and restricts the adjusting member 50 from floating in the radial direction with respect to the tappet main body 46. The peripheral wall surface 48 of the second accommodation space is a sliding contact surface with which the intervening member 55 is slidably contacted. The peripheral wall surface 48 of the second accommodating space allows the intervening member 55 to be displaced in the vertical direction, while restricting the intervening member 55 from waving in the radial direction with respect to the tappet main body 46. The diameter of the first accommodation space (inner diameter of the peripheral wall surface 47) is smaller than the diameter of the second accommodation space (inner diameter of the peripheral wall surface 48), and the intervening member 55 is restricted from entering the first accommodation space.

The adjusting member 50 is provided with a plurality of pressure receiving portions 51 that distribute and receive the load from the valve 20 side at the time of valve operation. The adjusting member 50 includes a plurality of lash adjusters 60 and a case 52 for accommodating the plurality of lash adjusters 60. The plurality of lash adjusters 60 are examples of a plurality of hydraulic control units capable of performing hydraulic control, respectively. The adjusting member 50 of this embodiment has two lash adjusters 60.

The case 52 has a substantially columnar shape as a whole, and is incorporated in the first storage space of the tappet main body 46. The case 52 has a plurality of recesses 53 into which each of the plurality of lash adjusters 60 is inserted. In this embodiment, the two lash adjusters 60 are arranged side by side on both sides of the central axis of the tappet bore 95 in a state of being inserted into the plurality of recesses 53.

The lash adjuster 60 has a bottomed tubular body 71 and a bottomed tubular plunger 81 that is movably inserted into the body 71 in the vertical direction. The body 71 has a circular bottom wall 72 and a cylindrical peripheral wall 73 rising from the peripheral edge of the bottom wall 72. A body oil hole 74 is provided through the peripheral wall 73 of the body 71. The plunger 81 has a circular bottom wall 82, a cylindrical peripheral wall 83 rising from the peripheral edge of the bottom wall 82, and a hemispherical top 85 provided at the upper end of the peripheral wall 83. A plunger oil hole 84 is provided through the peripheral wall 83 of the plunger 81. The radius of curvature of the outer peripheral surface (convex spherical surface) of the top portion 85 is smaller than the radius of curvature of the inner peripheral surface (concave spherical surface) of the bearing recess 35. A top hole 86 is provided through the center of the top 85.

A low pressure chamber 61 in which hydraulic oil is stored is provided in the plunger 81. Inside the body 71, a high pressure chamber 62 is formed which is partitioned from the low pressure chamber 61 by the bottom wall 82 of the plunger 81 and is filled with hydraulic oil. The bottom wall 82 of the plunger 81 is provided with a valve hole 63 penetrating between the low pressure chamber 61 and the high pressure chamber 62. Hydraulic oil is introduced and stored in the low pressure chamber 61 through the top hole 86. The high pressure chamber 62 is filled with the hydraulic oil of the low pressure chamber 61 through the valve hole 63. When the hydraulic oil serves as a lubricant in the valve gear 10, it is also referred to as a lubricating oil.

In the lash adjuster 60, the body oil hole 74 communicates with the low pressure chamber 61 in the plunger 81 via the plunger oil hole 84. When the lash adjuster 60 is assembled to the cylinder head and used for an OHC (OverHead Camshaft) engine, the body oil hole 74 and the plunger oil hole 84 communicate with the oil gallery of the cylinder head to reduce the pressure from the oil gallery. It was necessary for the hydraulic oil to flow into the chamber 61. In the case of this embodiment, since the existing lash adjuster 60 is used, the body oil hole 74 and the plunger oil hole 84 are formed in the lash adjuster 60.

The high-pressure chamber 62 houses a spherical valve body 64, a cage-shaped retainer 65, a first spring 66, and a second spring 67. The valve body 64 is housed in the retainer 65 and is arranged so that the valve hole 63 can be opened and closed. The first spring 66 is housed in the retainer 65 and urges the valve body 64 upward (in the direction of closing the valve hole 63). Further, the second spring 67 urges the retainer 65 upward. In the case of the first embodiment, the existing (general purpose) lash adjuster 60 is used as it is.

Each of the plurality of lash adjusters 60 has a pressure receiving portion 51. In this embodiment, the top portion 85 of the plunger 81 constitutes the pressure receiving portion 51. The plurality of pressure receiving portions 51 are configured to receive the lower end 42 side of the push rod 40. With the lash adjuster 60 inserted into the recess 53 of the case 52, the pressure receiving portion 51 is arranged so as to project into the second accommodating space of the tappet main body 46. In this embodiment, the valve gear 10 includes an intervening member 55 interposed between the push rod 40 and the plurality of pressure receiving portions 51. By interposing the intervening member 55 between the push rod 40 and the plurality of pressure receiving portions 51, for example, the push rod 40 is provided with a portion in contact with each of the plurality of pressure receiving portions 51. It is possible to prevent the structure from becoming complicated.

The intervening member 55 is a member that transmits the load from the push rod 40 to the plurality of pressure receiving portions 51 at the time of valve operation. The intervening member 55 has a disk shape and is housed in the second storage space of the tappet body 46. The intervening member 55 has an upper recess 56 provided on the upper plate surface and a plurality of lower recesses 57 provided on the lower plate surface. The upper concave portion 56 has a radius of curvature larger than the lower end 42 (convex spherical surface) of the push rod 40 and abuts on the lower end 42 of the push rod 40. The upper recess 56 is located at the center of the upper plate surface of the intervening member 55, and becomes the center of rotation when the tappet 45 rotates in the tappet bore 95. The lower recess 57 has a radius of curvature larger than the top 85 (convex spherical surface) of the plunger 81 in the lash adjuster 60, and abuts on the top 85 of the plunger 81. The plurality of lower recesses 57 are arranged on both sides of the upper recess 56, and the distances between the lower recesses 57 and the upper recesses 56 are the same.

The intervening member 55 is in sliding contact with the peripheral wall surface 48 of the second accommodating space in the tappet bore 95 when the valve clearance is adjusted. Specifically, when the plunger 81 moves up and down with respect to the body 71, the intervening member 55 slides up and down following the plunger 81. According to this configuration, the posture of the intervening member 55 is defined by the peripheral wall surface 48 of the second accommodating space, so that the operation of the intervening member 55 is stabilized and the load is balanced from the intervening member 55 to the plurality of pressure receiving portions 51. Can communicate well.

The intervening member 55 has an oil passage 58 provided so as to penetrate from the push rod 40 side toward the adjusting member 50 side. The oil passage 58 is composed of a plurality of through holes that open to the inner surface of the upper recess 56 and the inner surface of each of the plurality of lower recesses 57. The upper opening of the oil passage 58 is provided at a position corresponding to the opening on the lower end 42 side of the oil passage 43 of the push rod 40 in the upper recess 56. The oil passage 58 of the intervening member 55 communicates with the oil passage 43 of the push rod 40 in a state where the lower end 42 of the push rod 40 is in contact with the upper concave portion 56. It should be noted that the upper recess 56 or the lower end 42 of the push rod 40 is along the circumferential direction so that the oil passages 58 and 43 can communicate with each other even when the intervening member 55 rotates with respect to the push rod 40. A groove or the like extending may be provided. The lower opening of the oil passage 58 is provided at a position corresponding to the top hole 86 of the top 85 in the lower recess 57. With the top 85 in contact with the lower recess 57, the oil passage 58 of the intervening member 55 communicates with the plunger 81 via the top hole 86. In this way, a path for lubricating oil (hydraulic oil) is formed from the oil passage 43 of the push rod 40 to the plunger 81 via the oil passage 58 of the intervening member 55.

Next, the lubrication path for the lubricating oil from the rocker arm 30 side to the cam 97 side will be described.
The lubricating oil flowing through the oil passage 36 of the rocker arm 30 moves to the other end 32 of the rocker arm 30 and flows into the oil passage 43 of the push rod 40 via the adjust screw 33. The lubricating oil that has flowed into the oil passage 43 of the push rod 40 flows from the lower end 42 of the push rod 40 into the top holes 86 of the plurality of plungers 81 via the oil passage 58 of the intervening member 55. At this time, a part of the lubricating oil flows out from the oil passage 43 and the oil passage 58 to lubricate the sliding region of the push rod 40 and the intervening member 55 and the sliding region of the intervening member 55 and the top 85 of the plunger 81. To do.

A part of the lubricating oil that has flowed into the lash adjuster 60 from the top hole 86 of the plunger 81 flows out through the plunger oil hole 84 and the body oil hole 74, and is stored in the case 52 and the tappet body 46. .. In this embodiment, since the upper end of the tappet body 46 is located above the top 85 of the plunger 81, the hydraulic oil stored in the low pressure chamber 61 flows out through the plunger oil hole 84 and the body oil hole 74. Can be suppressed.

The lubricating oil that has flowed in beyond the storage amount of the tappet body 46 flows upward through the groove-shaped oil guide passage 59 provided on the peripheral end surface of the intervening member 55. The lubricating oil overflowing from the upper end of the tappet body 46 flows downward along the outer surface of the tappet body 46. This lubricating oil lubricates the tappet body 46, the tappet bore 95, and the sliding region. Further, the lubricating oil that wraps around the lower surface of the tappet body 46 lubricates the sliding region between the tappet body 46 and the cam 97.

Next, the operation mode of the valve gear 10 will be described. When the cam 97 rotates, the tappet 45 (tappet body 46) in contact with the cam 97 slides and displaces the tappet bore 95 in the vertical direction. At this time, the tappet 45 can rotate about an axis in the tappet bore 95. Specifically, when a rotational force acts on the tappet body 46 and the tappet body 46 rotates about an axis, the adjusting member 50 and the intervening member 55 rotate around the upper recess 56 located on the central axis of the tappet bore 95. In this embodiment, since the tappet main body 46 and the case 52 of the adjusting member 50 are separately configured, the rotational force of the tappet main body 46 is relaxed by sliding the case 52 with respect to the tappet main body 46. It can be transmitted to the adjusting member 50.

When the tappet 45 is slidably displaced in the vertical direction, the push rod 40 is moved up and down via the two lash adjusters 60 and the intervening member 55. The elevating operation of the push rod 40 is transmitted to the other end 32 of the rocker arm 30 via the adjusting screw 33, and the rocker arm 30 swings and displaces. Then, one end 31 of the rocker arm 30 moves up and down, and the two valves 20 are opened and closed synchronously via the valve bridge 22.

Here, when the intervening member 55 is strongly pressed downward from the push rod 40 side as the tappet body 46 rises, a load is applied from the intervening member 55 to the pressure receiving portion 51 (top 85 of the plunger 81) of the two lash adjusters 60. Is distributed and input. In this embodiment, the rotation of the tappet 45 in the circumferential direction moves the positions of the two lash adjusters 60 in the circumferential direction, and it is possible to prevent a large load from being applied only to one lash adjuster 60. Therefore, it is possible to prevent a specific pressure receiving portion 51 from being worn among the plurality of pressure receiving portions 51 of the adjusting member 50.

When a load is input from the intervening member 55 to the top 85 of the plunger 81, the valve body 64 closes the valve hole 63 in each of the lash adjusters 60, the plunger 81 and the body 71 become rigid, and the descent of the plunger 81 is restricted. Plunger. When the pressure acting on the plunger 81 decreases as the tappet body 46 descends, the volume of the high pressure chamber 62 increases as the second spring 67 pushes up the plunger 81, and the pressure in the high pressure chamber 62 decreases. As a result, the force for urging the valve body 64 in the valve closing direction decreases, the valve body 64 opens the valve hole 63, and the lubricating oil in the low pressure chamber 61 shifts to the high pressure chamber 62. In this way, the lift force of the cam 97 is damped and transmitted to the rocker arm 30 via the two lash adjusters 60, so that the valve clearance is automatically adjusted.

According to the valve gear 10 of the first embodiment, the load received by each of the plurality of pressure receiving portions 51 is reduced as compared with the configuration in which the load from the valve 20 side is received by a single pressure receiving portion during valve operation. Can be done. As a result, wear of the pressure receiving portion 51 can be suppressed. Specifically, as in this embodiment, assuming that the load applied to the adjusting member 50 from one valve 20 is Fv in the valve gear 10 including the two valves 20, the load applied to the adjusting member 50 from the valve 20 side. Fa is twice Fv multiplied by the rocker arm ratio (Fa = Fv × 2 × rocker arm ratio). Therefore, the load Fa applied to the adjusting member 50 may exceed the withstand load of the existing (general purpose) lash adjuster 60. In this embodiment, since the adjusting member 50 includes a plurality of lash adjusters 60, the load Fa applied to the adjusting member 50 is distributed and received by the top 85 of the plunger 81 in each lash adjuster 60, and the load applied to each lash adjuster 60 is received. It can be suppressed below the load capacity. Therefore, wear of the top of each lash adjuster 60 can be suppressed. Further, the insufficient load capacity of the lash adjuster 60 alone can be complemented by a plurality of lash adjusters 60, and can be used as the adjusting member 50 for high load capacity.

<Example 2>
FIG. 3 shows the adjusting member 150 of the second embodiment of the present invention. The second embodiment is different from the first embodiment in that the tappet main body 46, the case 52 of the adjusting member 50, and the tappet main body 146 having a configuration in which the body 71 of the lash adjuster 60 is integrated are provided. Other than that, it is the same as that of the first embodiment, and the description overlapping with the first embodiment will be omitted. In the following description, structurally the same or corresponding parts as those in the first embodiment are designated by the same reference numerals as those in the first embodiment.

The tappet body 146 has a plurality of plunger recesses 153 into which the plunger 81 is inserted so as to be reciprocally movable. The inside of the plunger recess 153 has the same configuration as the inside of the body 71 of the first embodiment. The adjusting member 150 is configured with a plurality of hydraulic control units 160 by inserting the plunger 81 into each of the plurality of plunger recesses 153. A low pressure chamber 61 and a high pressure chamber 62 are formed in each of the flood control units 160 as in the first embodiment. Each of these plurality of hydraulic control units 160 can perform hydraulic control.

According to the second embodiment, the adjusting member 150 can be configured by using the parts other than the body 71 of the existing (general purpose) lash adjuster 60 and the tappet main body 146. By providing the body 71 of the lash adjuster 60 integrally with the tappet body 146 together with the case 52, the number of parts of the adjusting member 150 as a whole can be reduced.

<Other Examples>
Hereinafter, other embodiments will be briefly described.
(1) The adjusting member may have a configuration in which a plurality of pressure receiving units are provided in one hydraulic control unit that performs hydraulic control for adjusting the valve clearance. Further, the adjusting member may be one that adjusts the valve clearance of one valve, or may be one that adjusts the valve clearance of three or more valves.
(2) The number of pressure receiving portions provided on the adjusting member may be 3 or more depending on the load applied to the adjusting member.
(3) The adjusting member may be provided on a member other than the tappet. For example, the adjusting member may be incorporated in the cylinder head. In such a configuration, the adjusting member may be a member that adjusts the valve clearance of various engines other than the OHV type engine.
(4) An intervening member may not be interposed between the push rod and the plurality of pressure receiving portions, and the load may be directly transmitted from the push rod to the plurality of pressure receiving portions. Further, the configuration of the intervening member can be changed as appropriate. For example, the intervening member may be in sliding contact with the inner peripheral surface of the tappet bore when adjusting the valve clearance.
(5) In the configuration of the first embodiment, the peripheral wall of the tappet main body and the peripheral wall of the case may be provided with an oil passage that communicates with the body oil hole and allows the lubricating oil to flow through. Further, in the configuration of the second embodiment, the peripheral wall of the tappet main body may be provided with an oil passage that communicates with the plunger oil hole and allows the lubricating oil to flow through.
(6) In the configuration of the first embodiment, the tappet main body and the case may be provided integrally.

10 ... valve gear, 20 ... valve, 30 ... rocker arm, 31 ... one end, 32 ... other end, 40 ... push rod, 41 ... upper end, 42 ... lower end, 45 ... tappet, 48 ... circumference of second accommodation space Wall surface (sliding contact surface), 50, 150 ... Adjusting member, 51 ... Pressure receiving part, 55 ... Intervening member, 58 ... Oil passage, 60 ... Rush adjuster (Flood control unit), 61 ... Low pressure chamber, 62 ... High pressure chamber, 63 ... valve hole, 64 ... valve body, 71 ... body, 81 ... plunger, 82 ... bottom wall, 85 ... top, 95 ... tappet bore, 97 ... cam, 160 ... hydraulic control unit

Claims (8)

A valve gear equipped with an adjusting member that adjusts the valve clearance by hydraulic control.
The valve gear is provided with a plurality of pressure receiving portions that distribute and receive the load from the valve side at the time of valve operation. The adjusting member includes a plurality of hydraulic control units.
The valve gear according to claim 1, wherein each of the plurality of the hydraulic control units has the pressure receiving unit. The hydraulic control unit is a lash adjuster.
The lash adjuster has a bottomed tubular body and a plunger that is inserted so as to be reciprocally movable with respect to the body.
A low-pressure chamber in which hydraulic oil is stored is provided in the plunger.
In the body, a high-pressure chamber is formed which is partitioned from the low-pressure chamber by the bottom wall of the plunger and is filled with the hydraulic oil.
A valve hole communicating between the low pressure chamber and the high pressure chamber is provided through the bottom wall of the plunger.
A valve body that opens and closes the valve hole is provided in the high-pressure chamber.
The valve gear according to claim 2, wherein the top of the plunger constitutes the pressure receiving portion. A rocker arm that swings around the rocker shaft to open and close the valve arranged at one end.
On the upper end side, a push rod that supports the other end side of the rocker arm, and
A tappet that reciprocally displaces while sliding on the inner peripheral surface of the tappet bore according to the rotation of the cam and transmits power to the push rod side is further provided.
The adjusting member is provided on the tappet and
The valve gear according to any one of claims 1 to 3, wherein the plurality of pressure receiving portions support the lower end side of the push rod. The valve gear according to claim 4, further comprising an intervening member interposed between the push rod and the plurality of pressure receiving portions. The valve operating device according to claim 5, wherein the intervening member is in sliding contact with a sliding contact surface in the tappet bore when adjusting the valve clearance. The valve gear according to claim 5 or 6, wherein the intervening member has an oil passage provided so as to penetrate from the push rod side toward the adjusting member side. The valve gear according to any one of claims 4 to 7, wherein the tappet is rotatable in the circumferential direction in the tappet bore.

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