JP4537418B2 - Sealed lash adjuster - Google Patents

Description

  The present invention relates to a sealed lash adjuster, and more particularly to a sealed lash adjuster provided with a sealing means between a plunger and a body.

  Conventionally, a lash adjuster that automatically adjusts a valve clearance provided between an intake / exhaust valve of an internal combustion engine and a cylinder head to substantially zero has been put into practical use. According to this lash adjuster, the noise generated by the interference between the intake / exhaust valve and the cylinder head is eliminated in terms of function, and the work of periodically checking and adjusting the valve clearance is unnecessary in terms of maintenance. The lash adjuster includes, for example, an external oil supply type that uses engine oil. In the case of this external lubrication type lash adjuster, if the injection amount of engine oil is inappropriate or if deteriorated oil is used as it is, there is an increased risk of air and foreign matter entering the oil. Function may be impaired. That is, in the external oil supply type lash adjuster, the function of the lash adjuster depends on the quality of engine oil maintenance. On the other hand, the lash adjuster includes a sealed lash adjuster in which a liquid such as oil is sealed. According to such a sealed lash adjuster, the above-described function inhibiting factors can be eliminated.

  As for this sealed lash adjuster, for example, the following sealed lash adjuster has been proposed in Patent Document 1. The sealed lash adjuster proposed by Patent Document 1 includes an oil seal (hereinafter simply referred to as an X seal) having two lips in a cross-sectional X-letter shape between a body and a plunger. This X seal can seal the two liquids on both sides of the seal at the same time. Therefore, in this sealed lash adjuster, the oil sealed by the X seal flows out to the outside and the engine oil enters from the outside at the same time. It is the structure for preventing.

Japanese Examined Patent Publication No. 62-29605

  By the way, in order to prevent the engine oil from being mixed into the oil sealed with the X seal, it is necessary to prevent mixing of two liquids (the engine oil and the oil sealed). For this purpose, the X seal is moved back and forth. It is necessary to function as a seal for use. In contrast, reciprocating seals generally require a lubricating oil film on the sliding surface to reduce wear, and functionally, the oil film that has come out in the pushing process returns to the inside in the pulling process. Is preventing. However, it is impossible to make the X seal function as a reciprocating seal.

  Here, the plunger stroke required for the lash adjuster is usually about 2 mm to 2.5 mm, and when the engine is stopped, the plunger sinks to the bottom of the body. When the plunger is extended most in the process, the sliding width (stroke) between the plunger and the body may exceed about 2 mm to 2.5 mm. In this regard, the X seal usually tries to maintain the sealing function by deformation without sliding with the body during the reciprocating movement of the plunger, but for example, due to the sudden expansion of the plunger when the engine is started, for example. It may slide with the body. Accordingly, in such a case, it is necessary to prevent the mixing of the two liquids by the movement of the oil film by causing the X seal to function as a reciprocating seal.

  On the other hand, the mixing of the two liquids due to the movement of the oil film occurs when the stroke of the plunger originally exceeds the width where the X seal contacts the body sliding surface. Therefore, in order to prevent mixing of the two liquids, an X seal having a size corresponding to the stroke of the plunger is required. On the other hand, the sealed lash adjuster is preferably as compact as possible from the viewpoint of increasing the degree of freedom in designing the internal combustion engine. However, in consideration of the plunger stroke, the X seal that can prevent mixing of two liquids is considered to inevitably increase the size of the sealed lash adjuster. Conversely, in the X seal that can be applied without increasing the size, It is considered difficult to prevent mixing of the two liquids. In other words, it is impossible to make the X seal function as a seal for reciprocating motion. From this, not only the sealed oil flows out to the outside with one sealing means provided between the body and the plunger. It was found that it was difficult to prevent engine oil from entering from the outside at the same time.

  Therefore, the present invention has been made in view of the above problems, and an object of the present invention is to provide a sealed lash adjuster that can prevent or suppress the intrusion of liquid from the outside and mixing into the liquid sealed inside.

In order to solve the above-mentioned problems, the present invention is attached to a plunger having a reservoir chamber therein, a first sealing means provided between the body into which the plunger is inserted, and a tip of the body. A sealed lash adjuster including a cap retainer that restricts the protrusion of the plunger, and includes a second sealing means that can prevent or suppress the intrusion of liquid from the outside, and the second sealing means includes: The cap retainer is provided so as to cover from the outside, seals a portion of the plunger exposed from the body, and covers a gap formed between the opening end of the body and the plunger. It is arranged. According to the present invention, since the functional part that prevents the sealed liquid from flowing out and the functional part that prevents the liquid from entering from the outside are separately provided, sealing can be performed more reliably. Thus, it is possible to prevent or suppress the intrusion of liquid from the outside and mixing into the liquid sealed inside. In addition, by disposing the second sealing means so as to cover the gap, not only intrusion of liquid from the outside but also invasion of fine chips can be effectively prevented or suppressed. The second sealing means may be sealed to the part exposed from the body to seal the part, and the part exposed from the body is slidably sealed to seal the part. May be.

  ADVANTAGE OF THE INVENTION According to this invention, the sealed lash adjuster which can prevent or suppress that a liquid penetrate | invades from the exterior and mixes in the liquid sealed inside can be provided.

  The best mode for carrying out the present invention will be described below in detail with reference to the drawings.

  FIG. 1 is a diagram schematically showing a sealed lash adjuster (hereinafter also simply referred to as a lash adjuster) 100A according to the present embodiment. The lash adjuster 100A includes a body 1, a plunger 2A, a check valve 3, a plunger spring 4, a first seal member (first seal means) 5, a ball plug 6, and a cap retainer 7 as basic components. It is comprised.

  The body 1 is a bottomed cylindrical member, and a plunger 2A is slidably inserted in the cylinder in a direction parallel to the central axis. A cap retainer 7 for restricting the protrusion of the plunger 2 </ b> A is disposed at the tip of the body 1. The cap retainer 7 functions to prevent the plunger 2 from coming off, and does not have a function of sealing a liquid entering from the outside. The plunger 2A is a cylindrical member, and a reservoir chamber 10 is formed inside. The reservoir chamber 10 may be formed in an appropriate shape. An injection hole 2aA for injecting oil (liquid) is formed on the distal end side of the plunger 2A, and a ball plug 6 for sealing the injected oil or gas is press-fitted into the injection hole 2aA. . A predetermined amount of oil is injected, and gas (for example, air obtained from the manufacturing atmosphere) exists in the remaining space of the reservoir chamber 10. For example, silicon oil can be applied as the oil to be sealed.

  A communication hole 2bA communicating with the high pressure chamber 11 is formed at the rear end of the plunger 2A, and a check valve 3 is disposed in the communication hole 2bA. A high pressure chamber 11 is formed on the rear end side of the plunger 2 </ b> A, and a plunger spring 4 is disposed in the high pressure chamber 11. The check valve 3 opens when the plunger spring 4 biases the plunger 2A so as to protrude toward the distal end side, and only allows the oil to move from the reservoir chamber 10 to the high pressure chamber 11 and blocks the reverse movement. To do.

  The plunger 2A is formed with a recycle hole 2cA that leads from the sliding surface to the reservoir chamber 10 so that the opening on the reservoir chamber 10 side is always closer to the high-pressure chamber 11 side than the oil level L of the oil in use. ing. Since the lash adjuster 100A according to the present embodiment is assembled to an internal combustion engine (not shown) in a state inclined by 45 degrees with respect to the vertical direction, the oil level L is shown in a state inclined by 45 degrees in FIG. .

  The recycle hole 2cA is formed so as to be orthogonal to the center axis toward the center axis, and the sliding surface of the plunger 2A has the same height (position in the sliding direction) as the recycle hole 2cA over the entire circumference. A groove 2dA is formed. Further, a groove portion 2eA is formed over the circumference of the sliding surface of the plunger 2 on the distal end side in the sliding direction, and a first seal member 5 for preventing oil leakage to the outside is formed in the groove portion 2eA. It is arranged. The first seal member 5 seals a slight gap between the body 1 and the plunger 2A on the tip side from the recycle hole 2cA. For example, an X seal can be applied to the first seal member 5, but the present invention is not limited thereto, and other appropriate sealing means such as other sealing parts may be applied.

  With the above configuration as the basic configuration of the lash adjuster 100A, in this embodiment, the lash adjuster 100A further includes a second seal member (second seal means) 20A. The second seal member 20A is configured to prevent or suppress intrusion of engine oil (liquid) from the outside. More specifically, engine oil is formed between the opening end of the body 1 and the plunger 2A. Preventing or suppressing intrusion into a gap K formed between them (more specifically, in this embodiment, a gap formed between the cap retainer 7 and the plunger 2A disposed at the opening end). It can be done. The second seal member 20A is exposed from the portion of the plunger 2A that is exposed from the body 1 (more specifically, from the body 1 in the state where the plunger 2A is most depressed, or from the cap retainer 7 in this embodiment). (Hereinafter, simply referred to as an exposed portion) is formed and disposed so as to cover the gap K.

  Specifically, the second seal member 20A includes one end portion 20aA and the other end portion 20bA as a seal portion having a function of preventing or suppressing intrusion of engine oil from the outside. In the present embodiment, rubber is applied to the material of the second seal member 20A, but the present invention is not limited to this, and an appropriate material may be applied. In the present embodiment, more specifically, the second seal member 20A is formed and arranged as follows.

  The exposed portion of the plunger 2A has a stepped shape 2fA on the outer periphery, and the ring-shaped first cap 21 abuts the stepped portion of the stepped shape 2fA against the stepped portion. Press fit. On the other hand, one end portion 20aA of the second seal member 20A forms an insertion hole S1 for inserting the exposed portion of the plunger 2A, and the second seal is formed by fitting the insertion hole S1 to the exposed portion. One end 20aA of the member 20A is in close contact with the exposed portion. In this state, the second cap 22 is further press-fitted into the exposed portion. As a result, the one end portion 20aA is sandwiched between the first and second caps 21 and 22. Thus, the one end portion 20aA is closely attached and fixed to the exposed portion of the plunger 2A, and functions as a seal portion that prevents intrusion of engine oil, thereby sealing the exposed portion.

  On the other hand, the second seal member 20A is relatively lightly in contact with the outer periphery of the lash adjuster 100A, specifically, the outer periphery of the body 1 in this embodiment, with one end 20aA fixed to the exposed portion. It is formed to do. In order to make the other end 20bA contact the body 1 relatively lightly, for example, a contraction force of rubber can be used. The relatively light contact state may be a state in which the other end portion 20bA is in close contact with the body 1 and at least partially contacts the body 1. Thereby, it functions as a seal part which prevents or suppresses intrusion of engine oil in a state where the other end 20bA is in contact with the outer periphery of the body 1. Accordingly, it is possible to prevent or suppress the engine oil from being mixed into the oil sealed inside from the outside by the one end portion and the other end portions 20aA and 20bA of the second seal member 20A.

  Further, since the other end portion 20bA is formed so as to be in contact with the outer periphery of the body 1, when the other end portion 20bA is assembled so as to be in contact with the outer periphery of the body 1, the second seal member 20A simultaneously forms the gap K. It arrange | positions so that it may cover. For this reason, intrusion of finer chips can be effectively prevented or suppressed. As described above, it is possible to realize the lash adjuster 100A that can prevent or suppress the engine oil from entering from the outside and mixing into the oil sealed inside.

  FIG. 2 is a diagram schematically illustrating the configuration of the lash adjuster 100B according to the present embodiment. The lash adjuster 100B is basically the same as the lash adjuster 100A shown in the first embodiment except that the plunger 2A is the plunger 2B. On the other hand, the lash adjuster 100B includes a second seal member 20B and the second seal member 20A in place of the second seal member 20A and the structures (first and second caps 21 and 22) associated with the second seal member 20A. Is different from the lash adjuster 100A in that it includes a configuration (retainer 23) associated with the lash adjuster 100A.

  Also in this embodiment, the second seal member 20B seals the exposed portion of the plunger 2B and is formed and disposed so as to cover the gap K. In this regard, in this embodiment, specifically, Thus, the second seal member 20B is formed and arranged. In the present embodiment as well, the second seal member 20B is provided with one end 20aB and the other end 20bB as a seal part having a function of preventing or suppressing intrusion of engine oil. Also in this embodiment, rubber is applied to the material of the second seal member 20B, but the present invention is not limited to this, and an appropriate material may be applied.

  A groove 2gB is formed on the outer periphery of the exposed portion of the plunger 2B, and a cylindrical retainer 23 is fixed to the groove 2gB by caulking. One end portion 20aB that forms the insertion hole S2 of the plunger 2B is fixed to the lower portion of the retainer 23 by vulcanization adhesion. For this reason, the upper end of the retainer 23 is caulked to the groove 2gB, so that the one end 20aB of the second seal member 20B is in close contact with and fixed to the exposed portion of the plunger 2. As a result, the one end portion 20aB functions as a seal portion that prevents intrusion of engine oil and seals the exposed portion.

  On the other hand, the second seal member 20B is relatively fixed to the outer periphery of the lash adjuster 100B, specifically, the outer periphery of the cap retainer 7 in this embodiment, with the one end 20aB fixed to the exposed portion. It is formed to touch lightly. Thereby, it functions as a seal part which prevents or suppresses intrusion of engine oil in a state where the other end 20bB is in contact with the outer periphery of the cap retainer 7. Accordingly, it is possible to prevent or suppress the engine oil from being mixed into the oil sealed inside by the one end portion and the other end portions 20aB and 20bB of the second seal member 20B.

  Further, since the other end portion 20bB is formed so as to be in contact with the outer periphery of the cap retainer 7, the second seal member 20B is simultaneously separated by a gap when the other end portion 20bB is assembled so as to be in contact with the outer periphery of the cap retainer 7. K is disposed so as to cover K. For this reason, intrusion of finer chips can be effectively prevented or suppressed. As described above, the lash adjuster 100B that can prevent or suppress the engine oil from entering from the outside and mixing into the oil sealed inside can be realized.

  FIG. 3 is a diagram schematically illustrating the configuration of the lash adjuster 100C according to the present embodiment. The lash adjuster 100C is basically the same as the lash adjuster 100A shown in the first embodiment except that the plunger 2A is the plunger 2C. The plunger 2C is the same as the plunger 2B shown in the second embodiment. On the other hand, the lash adjuster 100C includes a second seal member 20C and a structure (retainer 23) associated therewith instead of the second seal member 20A and the structure associated therewith as a part other than the basic structure. This is different from the lash adjuster 100A.

  Also in this embodiment, the second seal member 20C seals the exposed portion of the plunger 2C and is formed and disposed so as to cover the gap K at the opening end of the body 1. Specifically, in the example, the second seal member 20C is formed and arranged as follows. In the present embodiment as well, the second seal member 20C is provided with one end 20aC and the other end 20bC as a seal portion having a function of preventing or suppressing intrusion of engine oil. Also in this embodiment, rubber is applied to the material of the second seal member 20C, but the present invention is not limited to this, and an appropriate material may be applied.

  The one end portion 20aC of the second seal member 20C, like the one end portion 20aB described in the second embodiment, forms an insertion hole S3 of the plunger 2C and is fixed to the retainer 23. The retainer 23 is fixed to the plunger 2C. By caulking the groove portion 2gC, the one end portion 20aC is adhered and fixed to the exposed portion. Thereby, the one end portion 20aC functions as a seal portion that prevents the engine oil from entering, and seals the exposed portion.

  On the other hand, in the second seal member 20C, the one end portion 20aC is fixed to the exposed portion, and the other end portion 20bC is configured other than the lash adjuster 100C, specifically in the present embodiment, the cylinder head 30 of the internal combustion engine. It is formed so as to be attached (fixed) to the formed fixing portion 30a. The other end portion 20bC and the fixing portion 30a are formed so as to surround the lash adjuster 100C over one round. As a result, the other end portion 20bC is in close contact with the fixing portion 30a in a state where the other end portion 20bC is attached to the fixing portion 30a, and functions as a seal portion that prevents the engine oil from entering. Accordingly, it is possible to completely prevent the engine oil from being mixed from the outside into the oil sealed inside at the one end portion and the other end portions 20aC and 20bC of the second seal member 20C.

  Further, since the other end portion 20bC is formed so as to be attached to the fixing portion 30a of the cylinder head 30, the second seal member 20C covers the gap K at the same time when the other end portion 20bC is attached to the fixing portion 30a. It is arranged. For this reason, the invasion of finer chips can be prevented. In addition, in sealing the exposed portion in Example 1 to the present embodiment described above, it is preferable that the one end portion 20a is directly adhered and fixed to the exposed portion, and the exposed portion is sealed with the one end portion 20a. For example, the first or second cap 21, 22 or the retainer 23 may have a function of sealing the exposed portion. In this case, the second sealing member 20 and the first or second caps 21 and 22 and the retainer 23 realize the second sealing means. That is, the second sealing means may have a plurality of configurations, for example. As described above, it is possible to realize the lash adjuster 100C that can prevent the engine oil from entering from the outside and mixing into the oil sealed inside.

  FIG. 4 is a diagram schematically showing a lash adjuster 100D according to the present embodiment. The lash adjuster 100D is basically the same as the lash adjuster 100A shown in the first embodiment except that the plunger 2A is the plunger 2D. In addition to the basic configuration, the lash adjuster 100D further includes a second seal member 20D. The second seal member 20D is not essentially a component of the lash adjuster 100D, but is a lash adjuster 100D. Is different from the lash adjusters 100A to 100C shown in the first to third embodiments in that they are separate and independent parts. However, since the second seal member 20D is used at the same time in implementation, the second seal member 20D is also regarded as a component of the lash adjuster 100D in this embodiment. In other words, the second sealing means essentially includes an independent part that is separate from the lash adjuster, but also includes a component that is used at the same time as the lash adjuster. The plunger 2D is the same as the plunger 2A except that the stepped shape 2fA is not formed in the exposed portion.

  Also in the present embodiment, the second seal member 20D seals the exposed portion of the plunger 2D and is formed and disposed so as to cover the gap K. In this regard, in the present embodiment, specifically, Thus, the second seal member 20D is formed and arranged. In the present embodiment as well, the second seal member 20D is provided with one end 20aD and the other end 20bD as a seal portion having a function of preventing or suppressing intrusion of engine oil. Also in this embodiment, rubber is applied to the material of the second seal member 20D, but the present invention is not limited to this, and an appropriate material may be applied.

  Specifically, one end portion 20aD of the second seal member 20D forms an insertion hole S4 through which the exposed portion is inserted with a slight gap, and the one end portion 20aD has the plunger 2D inserted through the insertion hole S4. The exposed part is slidably sealed. Thereby, the one end portion 20aD functions as a seal portion that prevents or suppresses the intrusion of engine oil, and seals the exposed portion.

  On the other hand, the second seal member 20D has a configuration in which the other end 20bD is other than the lash adjuster 100D in a state in which the plunger 2D is inserted into the one end 20aD. It is formed so as to be attached and fixed to the fixing portion 30a. The other end portion 20bD and the fixed portion 30a are formed so as to surround the lash adjuster 100D over the entire circumference. In order to fix the other end portion 20bD to the fixing portion 30a, specifically, for example, a reduced-diameter protrusion is formed on the inner peripheral end of the other end portion 20bD, and the outer periphery of the fixing portion 30a corresponds to this. Although it can fix by forming a groove part and fitting the other end part 20bD to the fixing | fixed part 30a, it is not restricted to this, For example, you may fix by forming a female screw and a male screw, and screwing etc. .

  Thereby, it functions as a seal part which prevents intrusion of engine oil in a state where the other end portion 20bD is mounted and fixed to the fixing portion 30a. Accordingly, it is possible to prevent or suppress the engine oil from being mixed into the oil sealed inside by the one end portion and the other end portions 20aD and 20bD of the second seal member 20D. Further, since the other end portion 20bD is formed so as to be fixed to the fixing portion 30a of the cylinder head 30, the second seal member 20D covers the gap K at the same time when the other end portion 20bD is fixed to the fixing portion 30a. It is arranged. For this reason, even in this embodiment, it is possible to effectively prevent or suppress fine chips from entering. Further, in the present embodiment, since the second seal member 20D can also suppress the lateral movement of the plunger 2D, wear of the sliding portion between the plunger 2D and the body 1 can also be suppressed. As described above, it is possible to realize the lash adjuster 100D that can prevent or suppress the engine oil from entering from the outside and mixing into the oil sealed inside.

  FIG. 5 is a diagram schematically showing a lash adjuster 100E according to the present embodiment. The lash adjuster 100E shown in the present embodiment has the same basic configuration as the lash adjuster 100D described in the fourth embodiment. On the other hand, the lash adjuster 100E includes a second seal member 20E and a structure (seal housing 25) associated therewith instead of the second seal member 20D as a part other than the basic structure. It is different from 100D. Note that the second seal member 20E and the seal housing 25 are not essentially components of the lash adjuster 100E, but are independent components separate from the lash adjuster 100E. Similarly, the second seal member 20E and the seal housing 25 are regarded as one component of the lash adjuster 100E.

  In the present embodiment, the second seal member 20E seals the exposed portion of the plunger 2E in a slidable manner, and is disposed via a seal housing (holding member) 25 formed so as to cover the gap K. . In this regard, in the present embodiment, the lash adjuster 100E is specifically realized as follows.

  The seal housing 25 has an insertion hole S5 for inserting the plunger 2E, and a holding portion 25a for holding the second seal member 20E is further formed in the insertion hole S5. A metal (for example, iron or aluminum) can be used as the material of the seal housing 25. The second seal member 20E is assembled to the holding portion 25a by press-fitting, for example. In the present embodiment, the second seal member 20E is realized by a sealing component. Specifically, the second seal member 20E is, for example, a squeeze type such as an O-ring or an X-ring, a U-packing or a V-packet. Appropriate sealing parts such as a lip type such as packing can be applied. Thereby, an exposed part can be slidably sealed.

  On the other hand, the seal housing 25 has a flange portion 25c around a main body portion 25b formed so as to cover the gap K. Further, the flange portion 25c is formed so that the mating surface with the cylinder head 30 surrounds the lash adjuster 100E. The flange portion 25c is fixed to the cylinder head 30 of the internal combustion engine by a bolt 26. An appropriate sealing means may be further applied between the flange portion 25c and the cylinder head 30. Thereby, intrusion of engine oil from between the flange portion 25c and the cylinder head 30 can be prevented or suppressed. Accordingly, the second seal member 20E and the seal housing 25 can prevent or suppress the engine oil from being mixed into the oil sealed inside the lash adjuster 100E from the outside.

  Further, when the flange portion 25c is fixed to the cylinder head 30, the seal housing 25 is disposed so as to cover the gap K at the same time. For this reason, even in this embodiment, it is possible to effectively prevent or suppress fine chips from entering. Further, in the present embodiment, since the lateral movement of the plunger 2E can be suppressed by the second seal member 20E and the seal housing 25, wear of the sliding portion between the plunger 2E and the body 1 can also be suppressed. In addition, it is also possible to simplify the structure of the 1st seal member 5 by providing the 2nd seal member 20 from Example 1 mentioned above to a present Example. Specifically, for example, a single lip seal can be applied to the first seal member 5 instead of the X seal. As described above, the lash adjuster 100E that can prevent or suppress the engine oil from entering from the outside and mixing into the oil sealed inside can be realized.

  The embodiment described above is a preferred embodiment of the present invention. However, the present invention is not limited to this, and various modifications can be made without departing from the scope of the present invention.

It is a figure which shows typically the structure of 100A of lash adjusters. It is a figure which shows typically the structure of the lash adjuster 100B. It is a figure which shows typically the structure of 100C of lash adjusters. It is a figure which shows typically the structure of lash adjuster 100D. It is a figure which shows typically the structure of the lash adjuster 100E.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Body 2 Plunger 5 1st sealing member 7 Cap retainer 20 2nd sealing member 20a One end part 20b Other end part 21 1st cap 22 2nd cap 23 Retainer 25 Seal housing 30 Cylinder head 30a Fixing part 100 Sealing type Rush adjuster

Claims (1)

A plunger having a reservoir chamber therein; a first sealing means provided between the body into which the plunger is inserted; and a cap retainer that is attached to the tip of the body and restricts the protrusion of the plunger. A sealed lash adjuster comprising:
A second sealing means capable of preventing or suppressing entry of liquid from the outside;
The second sealing means is provided so as to cover the cap retainer from the outside, and seals a portion of the plunger exposed from the body, and between the opening end of the body and the plunger. A sealed lash adjuster, which is disposed so as to cover a gap formed in the casing.

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